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									    The 2005 Lake Hanas
International Pulsar Symposium

         Urumqi, Xinjiang, CHINA

             August 2-7, 2005




       Program & Abstracts
2
                       CONTENTS

Program in Brief                  P4

Program                           P5-P8

List of Participants              P9-P12

Abstracts                         P13-P72

Posters                           P73-P87




                                            3
                        Program in Brief



August 1: Registration and Reception at World Plaza Hotel, Urumqi
August 2: Registration; Opening ceremony; Public Lecture; Banquet;
          Session 1
August 3: Trip to Hanas, stop at Buerjin
August 4: Arrive Lake Hanas; Session 2
August 5: Sessions 3 & 4; Session 5 for posters session in the evening
August 6: Sessions 6; Sight-seeing and Boat Trip on Lake Hanas
August 7: Session 7; Back to Altay; Session 8, Closing Ceremony;
August 8: Back to Urumqi
August 9: Visit Nanshan and the 25m-radio telescope; Return to Urumqi




  4
The 2005 Lake Hanas International Pulsar
          Symposium Program

                    Monday August 1 (1030 – 2000)
Pulsar Workshop (1030 - 1300 & 1530 - 1830)

Registration and Reception(1200 - 2000)


     Tuesday August 2 At Urumqi (World Plaza Hotel)
Registration and Reception (1000 – 1100)

Opening Ceremony and Public Lecture (1100 – 1300) Chair: Shuhua Ye
  Dick Manchester – Einstein’s Gravity
Session 1: Pulsar Theory and Observations (1600 – 2000) Chair: Andrew
Lyne
  Na Wang – Pulsar Astronomy in China: Past, Present and Future (30m)
  Don Melrose – Pulsar Radio Emission Mechanisms (30m)
  Jennifer O’Brien – Sometimes a Pulsar (15m)

Coffee (1745 – 1815)
  Jaroslaw Dyks – Pulsar shade – Inward Radio Emission in Pulsar Magnetosphere (20m)
  Guojun Qiao – Annular Polar-cap Model of Gamma-ray Emission from Pulsars (15m)
  Peter Gonthier – The role of core and cone beams in radio pulsars (15m)
  Alex Judge – Polarisation Variations During the Escape of Pulsar Radio Emission (15m)



                 Thursday August 4 At Lake Hanas
Session 2: Pulsar Timing (1600 – 2000) Chair: Rendong Nan
  Fredrick Jenet – Pulsar Timing and Gravitational Wave Detection (30m)
  Dick Manchester – The Parkes Pulsar Timing Array (20m)
  Ben Stappers – The European Pulsar Timing Array (20m)
  Yuri Ilyasov – Millisecond Pulsar Timing at Kalyazin Observatory (20m)
  Alexander Rodin – Ensemble Pulsar Timescale (15m)

Coffee (1745 – 1815)

                                                                                          5
  Andrew Lyne – Review of the Double Pulsar J0737-3039 (30m)
  Scott Ransom – Pulsar Science with the GBT (30m)
  George Hobbs – Pulsar Timing Noise (20m)
  Andrea Possenti – Timing of Globular Cluster Pulsars at Parkes (20m)



                                   Friday August 5
Session 3: Interstellar Medium (1000 – 1400) Chair: Simon Johnston
  Barney Rickett – Pulsar Scintillation I – Introduction to Interstellar Scattering and the Effects of
                   Anisotropy (30m)
  Dan Stinebring – Pulsar Scintillation II – Turbulence and Structure in the ISM (30m)
  William Coles – Scintillation observations of the double pulsar J0737-3039 (20m)
  Chengmin Zhang – Stationary Phase Point Method for Interstellar Scattering (15m)

Coffee (1145 – 1215)
  Jinlin Han – Galactic Magnetic Field Probed by Pulsars (30m)
  Amrit Lal Ahuja – Probing Pulsar DMs using the GMRT (15m)
  Xingwu Zheng – The Distance to the Perseus Spiral Arm (15m)
  Yefei Yuan – Rotational Evolution of Protoneutron Stars (15m)
  Wei Wang – Millisecond Pulsar Population in the Galactic Centre and High Energy
             Contributions (15m)
  Qinghuan Luo – Dissipation of Low-Frequency Waves in Pulsar Winds (15m)
Session 4: Pulsar Theory and Observations (1600 – 2000) Chair: Valery
Malofeev
  Qiuhe Peng – Origin of Glitches of Pulsars (20m)
  Tatiana Smirnova – Pulse Intensity Distribution in the Emission Zone of PSR B0950+08
                     (20m)
  Patrick Weltevrede – Statistics on the Drifting Subpulse Phenomenon (15m)
  Russell Edwards – Seeing Triple – Polarised Views of the Drifting Subpulse Phenomenon
                    (15m)
  Roy Smits – The Drifting Subpulses of PSR B0031-07 (15m)
  Honguang Wang – Observational Constraints on the Emission Region for PSR B1055-52
                  (15m)

Coffee (1745 – 1815)
  Haydon Knight – Giant Pulses from Millisecond Pulsars (20m)
  Arkady Kuzmin – Giant Pulses of Pulsars' Radio Emission (20m)
  Svetlana Petrova – Origin of Giant Pulses in Radio Pulsars (30m)
  Natasa Vranesevic – What is Special about High-B Pulsars? (15m)
  Weizhen Zou – Pulsar Timing at Urumqi Observatory (15m)


  6
Session 5: Poster Session (2130 – 2300) Chair: Dick Manchester
  Short presentation with 1 page/2 min from poster presenters



                              Saturday August 6
Session 6: Neutron Stars – Origin and Evolution (1000 – 1400) Chair:
Barney Rickett
  Simon Johnston – Evidence for the Alignment of the Rotation and Velocity Vectors in Pulsars
                   (20m)
  Dong Lai – Spin, Magnetism and Velocities of Young Neutron Stars (20m)
  Ali Esamdin – Pulsar glitches in the Jodrell Bank Database (15m)
  Valerij Malofeev – Radio Emission of Anomalous X-ray Pulsars (20m)
  Biping Gong – The Same Physics Underlying SGRs, AXPs and Radio Pulsars (15m)
  Igor Malov – Nature of Magnetars (15m)
  Shuang Nan Zhang – Radio Pulsars as Progenitors of AXPs and SGRs (15m)

Coffee (1200 – 1220)
  Renxin Xu – Pulsars and Quark Stars (20m)
  George Melikidze – A Model for MP/IP anti-correlation in PSR B1822-09 (20m)
  Janusz Gil – Phenomenon of Drifting Subpulses (20m)
  Jaroslaw Kijak – A New Aspect of Pulsar Radio Spectra (15m)
  Bing Zhang – High Energy Emission from Pulsars (15m)
  Xinji Wu – The Distribution of Old Neutron Stars and GRBs (15m)


Sight seeing and Boat Trip on Lake Hanas


                                Sunday August 7
Session 7: Techniques and Next-Generation Telescopes (1000 – 1300) Chair:
Ben Stappers
  Rendong Nan – Pulsar Observations with the FAST telescope (25m)
  Joeri van Leeuwen – Arecibo and the ALFA Pulsar Survey (25m)
  Rick Jenet – Report on the Penn State Timing Array Meeting (25m)

Coffee (1115 – 1145)
  Chengjin Jin – The Miyun 50m Pulsar Radio Telescope (25m)
  Richard Strom – How Might LOFAR and the SKA Impact Pulsar Astronomy (25m)
  Simon Johnston – Australia and the SKA (25m)

Session 8: Closing Ceremony (2000 – 2200) At Altay


                                                                                        7
8
               LIST OF PARTICIPANTS
Ahuja, Amrit Lal, ahuja@iucaa.ernet.in, IUCAA, Pune, India, India
ALBERT, DONALD, uni_ado_ekiti_nigeria@yahoo.com, UNIVERSITY OF
ADO-EKITI, NIGERIA
An, Tao, antao@shao.ac.cn, Shanghai Astronomical Observatory, China
Baruah, Rulee, ruleebaruah@yahoo.co.in, Prince of Wales Institute of Engg. and
Technology, India
Buchner, Sarah, sarah@hartrao.ac.za, Hartebeesthoek Radio Astronomy, South
Africa
CHATTERJEE, Tapan Kumar, chtapan@yahoo.com, University of the Americas
(UDLA , Phys.-Mat.), MEXICO
CHEN, Ding, cding@shao.ac.cn, Shanghai Astronomical Observatory, Chinese
Academy of Sciences, China
Chen, Yi, ychen@niaot.ac.cn, Nanjing Institute of Astronomical Optics &Technology
National Astronomical Observatories, CAS, China
Chen, Li, chenli@bnu.edu.cn, Department of astronomy, Beijing Normal University,
China
Chou, Chih-Kang, NOAC, cas, china
Coles, William, bcoles@ucsd.edu, University of California at San Diego, USA
Cui, Xiaohong, xhcui@vega.bac.pku.edu.cn, Peking University, China
Dong, Jiang, dongj@ms.xjb.ac.cn, Urumqi Observatory, china
Dyks, Jaroslaw, jinx@physics.unlv.edu, Nicolaus Copernicus Astronomical Center,
Poland
Edwards, Russell, Russell.Edwards@csiro.au, Australia Telescope National
Facility, Australia
Ershov, Alexander, ershov@prao.psn.ru, Pushchino RadioAstronomy Observatory,
Lebedev Physical Institute, Russia
Esamdin, Ali, aliyi@ms.xjb.ac.cn, Urumqi Observatory, NAOs-CAS, P R China
Estelle, Asseo, asseo@cpht.polytechnique.fr, cpht, france
Fan, Junhui, jhfan_cn@yahoo.com.cn, CfA, Guangzhou University, China
Gao, Yifei, gyf@mail.ynao.ac.cn, Yunnan Ovservatory, CASC, China
Gil, Janusz, jag@astro.ia.uz.zgora.pl, Institute of Astronomy, University of Zielona
Gora, Poland
Gong, Biping, bpgong@nju.edu.cn, Nanjing University, China
Gonthier, Peter, gonthier@hope.edu, Hope College, USA
Gupta, Yashwant, ygupta@ncra.tifr.res.in, National Centre for Radio Astrophysics
(TIFR), India
Han, JinLin, hjl@bao.ac.cn, NAOC, China
He, Qiuhui, qhhe@nju.edu.cn, Astronomy Department of Nanjing University, China
Hobbs, George, george.hobbs@csiro.au, Australia Telescope National Facility,
Australia
Hong, Bihai, hbh_1217@126.com, Department of Physics, Lishui University, P. R.
                                                                               9
China
Huang, Xinyong, xhuang@center.shao.ac.cn, Shanghai Observatory, China
Hussain, Sadiq, sadiq_edu@yahoo.com, Swabi Institute of Sciences and
Technology, Pakistan
Hussain, shah, shah_hedu@yahoo.com, Swabi Institute of Sciences and
Technology, Pakistan
Hussain, Shah, shah_hedu@yahoo.com, Swabi Institute of Sciences and
Technology, Pakistan
Ilyasov, Yuri, ilyasov@prao.psn.ru, Lebedev Physical Institute Russian Academy of
Sc, Russia
Jenet, Fredrick, merlyn@alum.mit.edu, University of Texas at Bownsville, USA
Jin, Chengjin, cjjin@bao.ac.cn, National Astronomical Observatories, CAS, China
Johnston, Simon, simon.johnston@csiro.au, CSIRO, ATNF, Australia
Judge, Alexander, ajudge@physics.usyd.edu.au, University of Sydney, Australia
Kiang, Tao, tkiang2005@yahoo.ie, Dunsink Observatory, Dublin, Ireland
Kijak, Jaroslaw, jkijak@astro.ia.uz.zgora.pl, Institute of Astronomy, University of
Zielona Gora, Poland
Knight, Haydon, hknight@astro.swin.edu.au, Swinburne University of
Technology/ATNF, Australia
Kong, Lingjun, augustkong@126.com, Urumqi Observatory, National Astronomical
Observatories of CAS, China
Kuzmin, Arkady, akuzmin@prao.psn.ru, Pushchino Radio Astronomy Observatory
of the Lebedev Physical Institute, Russian Federation
Lai, Dong, dong@astro.cornell.edu, Cornell University, USA
Lee, Kejia, k.j.lee@water.pku.edu.cn, Peking Univeristy, P.R.China
Li, Xiang-Dong, lixd@nju.edu.cn, Department of Astronomy, China
Liu, Qingzhong, qzliu@pmo.ac.cn, purple Mountain Observatory, China
Liu, Xiang, liux@ms.xjb.ac.cn, Urumqi Observatory, NAOCAS, China
Liu, Liyong, liuly@ms.xjb.ac.cn, Urumqi Observatory, NAOs-CAS, China
Liu, ZhiYong, liuzy@ms.xjb.ac.cn, Urumqi Observatory, NAO-CAS, China
Liu, Yi, yliu@center.shao.ac.cn, Shanghai Astronomical Observatory, China
Liu, Yi, Pinux@pku.org.cn, CFA, Guangzhou University, China
Lu, Ju-Fu, lujf@xmu.edu.cn, Xiamen University, China
Luo, Qinghuan, luo@physics.usyd.edu.au, School of Physics, The University of
Sydney, Australia
Luo, Shaoguang, Beijing University, China
Lyne, Andrew, agl@jb.man.ac.uk, University of Manchester, UK
Malofeev, Valery, malofeev@prao.psn.ru, Lebedev Physical Institute, Pushchino
Radio Astronomy Observatory, Russia
Malov, Igor, malov@prao.psn.ru; igor_malov@list.ru, Lebedev Physical Institute,
Russian Academy of Sciences, Russia
Manchester, Dick, dick.manchester@csiro.au, ATNF - CSIRO, Australia
Melikidze, George, gogi@astro.ia.uz.zgora.pl, Institute of Astronomy, University of
Zielona Góra., Poland

   10
Melrose, Don, melrose@physics.usyd.edu.au, School of Physics, Australia
Mitra, Dipanjan, dmitra@ncra.tifr.res.in, National Centre for Radio Astrophysics,
TIFR, India
Morris, David, morris@iram.fr, Institute de Radioastronomie Millimetrique, France
Nan, Rendong, nrd@bao.ac.cn, NAOC, China
O'Brien, Jennifer, jto@jb.man.ac.uk, Jodrell Bank, England
Peng, Qiu-he, qhpeng@nju.edu.cn, Department of Astronomy, Nanjing University,
China, China
Petrova, Svetlana, petrova@ira.kharkov.ua, Institute of Radio Astronomy NAS of
Ukraine, Ukraine
Possenti, Andrea, possenti@ca.astro.it, INAF-Cagliari Observatory, Italy
Qiao, Cui lan, joecl@126.com, Department of Astronomy,Nanjing
University;Department of Physics,Huazhong Normal University, China
Qiao, Guo jun, Beijing University, China
Ransom, Scott, sransom@nrao.edu, NRAO, USA
Rickett, Barney, rickett@ece.ucsd.edu, University of California San Diego, USA
Rodin, Alexander, rodin@prao.psn.ru, Pushchino Radio Astronomy Observatory of
the Lebedev Physical Institute of the Russian Academy of Sciences, Russia
Salay, Burhan, burhan_salay@yahoo.com.cn, Physics Dept. of Xinjiang University,
China
Shang, Rencheng, src-dmp@tsinghua.edu.cn, Tsinghua Center for Astrophsics,
China
Shen, Zhi-Qiang, zshen@shao.ac.cn, Shanghai Astronomical Observatory, NAOC,
China
Smirnova, Tatiana, tania@prao.psn.ru, Pushchino Radioastronomy observatory of
the Lebedev Physical Institute, Russia
Smits, Roy, R.Smits@astro.ru.nl, Department of Astrophysics, Radboud University
Nijmegen, The Netherlands
Stappers, Ben, stappers@astron.nl, Stichting Astron, Netherlands
Stinebring, Daniel R., dan.stinebring@oberlin.edu, Oberlin College, USA
Stinebring, Jesse P., dan.stinebring@oberlin.edu, Oberlin High School, USA
Strom, Richard, strom@astron.nl, ASTRON (& University of Amsterdam), Netherlands
Sun, Zhengwen, Urumqi Obervatory, NAOC-CAS, China
van Leeuwen, Joeri, joeri@astro.ubc.ca, University of British Columbia, Canada
van Straten, Willem, free.willem@gmail.com, University of Texas at Brownsville,
United States of America
Vranesevic, Natasa, natasa@physics.usyd.edu.au, University of Sydney/ATNF,
AUSTRALIA
Wang, Wei, wwang@lamost.bao.ac.cn, National Astronomical Observatories, China
Wang, Min, wmynao@163.net, Yunnan Ovservatory, CASC, China
Wang, Jinbu, wjb@ nairc.ac.cn, CAS Nanjing Astronomical Instrument Co.,Ltd,
China
Wang, Hongguang, cosmic008@263.net, Center for Astrophysics, Guangzhou
University, China

                                                                              11
Wang, Na, na.wang@ms.xjb.ac.cn, Urumqi Obervatory, NAOC-CAS, China
Wang, Yongxiang, yongxiang_w@163.com, Science & Technology College
Guangzhou University, China
Wang, Chen, wangchen@bao.ac.cn, NAOC, P.R.China
Weltevrede, Patrick, wltvrede@science.uva.nl, Astronomical Institute "Anton
Pannekoek", the Netherlands
Wu, Xinji, Beijing University, China
Xie, Yi, shea@citiz.net, Astronomy Department of Nanjing University, China
Xu, Renxin, r.x.xu@pku.edu.cn, School of Physics, Peking University, China
Yan, Jingzhi, jzyan@pmo.ac.cn, Purple Mountain Observatory, China
Yan, Zhen, hiyanzhen@126.com, Urumqi Observatory, NAOs-CAS, China
Yang, Dong, dongyang@tsinghua.edu.cn, Tsinghua Center for Astrophsics, China
Yang, Dehua, dhyang@niaot.ac.cn, Nanjing Institute of Astonomical Optics and
Technology, PRC
Yang, Tinggao, yangtg@ntsc.ac.cn, National Time Service Center, CAS, China
Yang, Jianghe, yjianghe@163.com, hunan university of arts and science, china
Ye, Shuhua, Shanghai Astronomical Observatory, china
You, Xiaopeng, xpyou@bao.ac.cn, NAOC, China
You, Junhan, jhyou@online.sh.cn, Institute for space astrophysics,Shanghai
Jiao-Tong University, China
Yuan, Yefei, yfyuan@ustc.edu.cn, Center for Astrophysics, University of Science
and Technology of China, China
Yuan, JianPing, yjp611@126.com, Urumqi Observatory, National Astronomical
Observatories of CAS, China
Yue, Youling, yueyl@vega.bac.pku.edu.cn, School of Physics, Peking University,
China
Yusup, Ali, Urumqi Observatory, NAOs-CAS, P R China
Zhang, Bing, China
Zhang, Shuang Nan, zhangsn@tsinghua.edu.cn, Tsinghua University, China
Zhang, Chengmin, zhangcm@bao.ac.cn, National Astronomical Observatories,
China
Zhang, Hui, red_violin2004@yahoo.com.cn, NAOC, P.R.China
Zhang, Huawei, zhw@bac.pku.edu.cn, Peking University, P.R. China
Zhang, Jin, Urumqi Observatory, NAOs-CAS, P R China
Zhao, Jie, pangwn@tsinghua.edu.cn, Tsinghua Center for Astrophsics, China
Zhao, Jingzhi, zjz@bao.ac.cn, zjz@chjaa.org, National Astronomical
Observatories, Chinese Academy of Sciences, China
Zheng, Xiaoping, zhxp@phy.ccnu.edu.cn, The institute of astrophysics, Huazhong
normal university, China
Zheng, Xingwu, xwzheng@nju.edu.cn, Nanjing University, China
Zhou, Yulan, zyl@pmo.ac.cn, Purple Mountain Observatory, China
Zhou, Aizhi, zaiz@center.shao.ac.cn, Shanghai Observatory, China
Zou, Weizhen, zouwz@ms.xjb.ac.cn, Urumqi Observatory, NAOs-CAS, China


   12
ABSTRACTS
Einstein's Gravity
  Dick Manchester




                     13
    Pulsar astronomy in China: past, present and future
                                   Na Wang

This talk will introduce Chinese pulsar people and their progress on
observational and theoretical pulsar studies. Prospects for future radio
telescopes are also reviewed.




  14
               Pulsar radio emission mechanisms
                                Don Melrose

Pulsar radio emission mechanisms will be reviewed emphasizing severe
constraints imposed by evidence that the radiation often emerges in two
orthogonally polarized modes with nearly equal intensities. Evidence on the
location of the radio emission regions will also be reviewed critically.




                                                                         15
     Pulsar polarisation
       Willem van Straten




16
   A model for MP/IP anti-correlation in PSR B1822-09
                      George Melikidze, J. Gil, B. Zhang

A model for PSR B1822-09 was recently proposed by Dyks, Zhang and Gil
(ApJ, 2005, 626, L45), which implies the reversals of radio emission direction
to explain the MP and IP behavior. Here we discuss possible scenario that
allows to explain the anti-correlation between MP sand IP. We assume that
the working regime of the inner gap is influenced by the outer gap. Depending
on the surface temperature of the polar cap, one can expect alteration of the
mean Lorentz factors of the secondary particles, which drastically affects the
radio emission process.




                                                                         17
       Pulsar shade - inward radio emission in pulsar
                            magnetosphere
Jaroslaw Dyks, M. Frackowiak, Agnieszka Slowikowska, B. Rudak, Bing Zhang

We show that 'double notches' observed in averaged pulse profiles of nearby
radio pulsars can be naturally explained as two eclipses of radially extended
region of inward radio emission by the pulsar. The geometry of dipolar
magnetic field of pulsars favours such double eclipse events. For large
inclination and viewing angles two consecutive eclipses take place about 20 to
30 degrees before the main radio peak. Moreover, the presence of radially
extended and inwardly directed (in addition to outward) radio emission has
other profound observational consequences. In particular, we argue that such
inward emission may be responsible for the morphological richness of pulsar
radio profiles, in particular of those with spurious interpulses. Other
phenomena, like profile mode changes and the anti-BCW shift of position
angle curves, can also be naturally interpreted in terms of the inward radio
emission in pulsar magnetosphere.




  18
High energy emission from pulsars
            Bing Zhang




                                    19
 Annular polar cap model of Gamma-ray emission of
                     pulsars
                    Guojun Qiao




20
      The role of core and cone beams in radio pulsars
  Peter Gonthier, S.A. Story, B.M. Giacherio, R.A. Arevalo and A.K. Harding

We seek to constrain the magnetic inclination and impact angles at available
frequencies of a sample of radio pulsars that have clearly identifiable core and
cone components in their profiles. We constrain the maximum rate of change
of the position angle (PA) by fitting the rotating vector model to the position
angle swing. Assuming core and cone beam geometries and the maximum
rate of change of the PA, we constrain the inclination angle by fitting the
intensities of the profiles allowing for the determination of both the inclination
and impact angles. We incorporate three different size cones with a frequency
dependence from the work of Mitra and Deshpande (1999). The fits allow us to
obtain separate spectral indices of the angle-integrated flux (over the emission
surface) as well as luminosities, assuming pulsar distances, for the core and
cone beams and explore the trends with period and period derivative. This
ratio of the core-to-cone peak fluxes is observed to increase with period up to
periods of about 0.7 s and then decrease with increasing period at all
frequencies. The trend of this ratio for short period pulsars differs from an
extrapolation of the relation given by Arzoumanian, Chernoff & Cordes (2002)
for pulsars with longer periods. . We will present our current findings and
implications for our population statistics synthesis and radio and gamma-ray
profile correlation studies.




                                                                             21
 Polarisation variations during the escape of pulsar radio
                                 emission
                       Alexander Judge, D. B. Melrose

Models for the natural modes and the propagation of rays in pulsar
magnetospheres are combined to predict the evolution of the polarisation of
radio emission during escape from the magnetosphere of a pulsar. The
concept of a polarisation limiting region and its relation to the observed
polarisation is discussed.




  22
       Pulsar timing and gravitational wave detection
               Fredrick Jenet, George Hobbs, Dick Manchester

Radio pulsars offer a unique opportunity to probe the nano-hertz regime of the
gravitational wave (G-wave) spectrum. Such low frequency G-waves will
provide a wealth of information about galaxy and supermassive black hole
binary formation and evolution. The most likely signal detected using pulsar
timing will be a stochastic G-wave background generated from an ensemble of
supermassive black holes scattered throughout the universe. Techniques are
currently being developed to detect such a background. Aside from the
background, radio pulsars can place limits on the existence of individual
G-wave sources. Using currently available data, limits have been placed on
the mass of a proposed supermassive black hole system in the radio galaxy
3C 66B.




                                                                         23
                 The Parkes pulsar timing array
                              Dick Manchester

The Parkes Pulsar Timing Array is a collaborative project between the
Swinburne University of Technology, the University of Texas, Brownsville, and
the ATNF which has as its principal goal using precision timing of millisecond
pulsars to make a direct detection of gravity waves. The Parkes 64-m
telescope is being used to time a sample of 20 MSPs at three frequencies,
700, 1400 and 3100 MHz, with observations at 2 - 3 week intervals. New
instrumentation and signal processing systems are being developed to reach
the goal of 100-nanosecond timing precision on at least half of the sample.




  24
                The European pulsar timing array
           Ben Stappers, Kramer, Lyne, Jessner, D'Amico, Zensus

The timing of radio pulsars provides a tool for studying a wide range of
fundamental physical and astrophysical problems. The best results are
obtained by regular, frequenct timing observations of a large number of
sources at various frequencies. We describe a project which aims to improve
on all of the above parameters by combining timing data from the pulsar timing
programs of 4 European groups to form the so-called EPTA. These data will
be used to study, amongst other things, relativistic binaries and gravitational
waves.




                                                                          25
       Millisecond pulsars timing at Kalyazin observatory
                                  (Russia)
                                  Yuri Ilyasov

Timing of seven binary pulsars an Backer B1937+21 one are made in long
time from 1996 till to now at Kalyazin observatory, where 64-m dish radio
telescope full sterable is constructed. This is very quiet zone from interference
protected by the Frequency Regulation on 0.6 and 1.4 GHz. Receivers with
LNA (colled at 1.4 GHz are installed on instrument. H-masers and
Rb-standards are used in local time service together with GPS receivers.
DeDispersion technique is used off-line. Some time Acousto-optical processor
is applied as real time dispersion remover. The main results are discussed in
presentation including pulsars VLBI by Kalyazin (Russia)-Kashima (Japan)
baseline.




  26
                    Ensemble pulsar time scale
                              Alexander Rodin

Algorithm of ensemble pulsar time (PT) scale based on Wiener filters is
presented. Corrections of atomic time scale relative to ensemble PT scale
have been obtained. It has been shown that stability of PT is comparable with
stability of terrestrial time scale TT at interval of several years.




                                                                         27
           Review of the Double Pulsar J0737-3039
                                Andrew Lyne

We will review the current status of observation of PSRs J0737-3039A and B
and the prospects for the future. The review will address post-newtonian
gravitational effects, interactions between the pulsars, the magnetospheric
eclipse of A by B and interstellar scintillation observations of the system.




  28
                     Pulsar science with the GBT
                                  Scott Ransom

With its large area, excellent receivers, state-of-the-art instruments, relatively
quiet interference environment, and ability to see a large fraction of the sky,
the GBT is undoubtedly one of the best telescopes available for pulsar
observations. In this talk I will present updates on some recent GBT pulsar
projects including searches, timing, and other experiments. I will spend a
significant amount of the time discussing the fantastic zoo of pulsars we have
recently uncovered in the globular cluster Terzan 5.




                                                                              29
                           Pulsar timing noise
                       George Hobbs, A. Lyne, M. Kramer

I will present the most recent results from studying timing irregularities in the
timing residuals of 370 pulsars. I will discuss theoretical models for pulsar
timing noise and how these can be analysed or disproved using the timing
observations.




   30
         Timing of globular clusters pulsars at Parkes
   Andrea Possenti, Corongiu A., Camilo, F., Manchester, R.N., Lyne, A.G.,
                        D'Amico, N., Sarkissian, J.

Timing observation of millisecond pulsars embedded in globular clusters have
proven to be very powerful tools for attacking many interesting scientific topics,
such as the study of the potential well of a globular cluster, the dynamical
interactions in the globular cluster core, the gas content in the globular, the
neutron star retention, the binary evolution in a very dense stellar environment
and the equation of state for the nuclear matter. I here report on some of the
most recent results derived from combining timing observations performed at
the Parkes radiotelescope with observations at other wavelengths of globular
cluster pulsars.




                                                                             31
        Pulsar scintillation I - introduction to interstellar
              scattering and the effects of anisotropy
                                 Barney Rickett

Pulsar observers have to contend with several effects of propagation through
the ionized interstellar medium. I will review those effects and how on one
hand they can be corrected and how on the other hand they can be used to
study the interstellar plasma. Pulsars are normally observed under conditions
of strong scintillation and show both diffractive and refractive effects. I will
emphasize the diffractive scintillation as exhibited in the dynamic spectrum
and in its converse -- pulse broadening. I will show various observations of
pulse broadening, including one from which I estimate the inner scale in an
interstellar region of strong plasma turbulence. I will discuss the representation
of dynamic spectra in terms of their "secondary spectra" and show how the
arcs, that are often revealed, are related to both angular broadening and pulse
broadening. Throughout I will emphasize the role of anisotropy in the
scattering.




   32
Pulsar scintillation II - turbulence and structure in the
                                      ISM
                              Daniel R. Stinebring

Recent high sensitivity measurements of pulsar scintillation, particularly with
high frequency resolution, have revealed a wealth of new details.
Concentrating on the secondary spectrum, I will discuss examples of simple
scintillation arcs (parabolic features in the secondary spectrum) as well as
more complicated features. The following phenomena will be discussed within
the context of a multiple thin screen model: multiple scintillation arcs, inverted
arclets, and systematic motion of substructure. Spatially intermittent
turbulence appears to be needed to explain the observations. I will also
discuss the possible connection between features in secondary spectra and
those structures responsible for extreme scattering events in quasar flux
monitoring. Finally, some preliminary efforts (by M. Walker) to image the
scattering screen will be presented.




                                                                             33
Scintillation observations of the double pulsar J0737-3039
             William Coles, Barney Rickett and Maura McLaughlin

The double pulsar is a remarkable system for study of general relativity, binary
kinematics, and pulsar magnetospheres. Interstellar scintillation of this system
is also very interesting because scintillations of the two pulsars can be
observed separately and cross correlated. This cross correlation provides a
very direct measurement of the angular separation of the pulsars at the closest
point of approach and thus the orbital inclination. The cross correlation can
also be mapped into a spatial correlation, which shows that the interstellar
turbulence is quite anisotropic. When this anisotropy is included in the
scattering model the calculated transverse velocity of the center of mass is
greatly reduced. Parabolic arcs can be observed in the secondary spectra of
this system and the analysis of these arcs confirms the anisotropy determined
earlier. This also confirms that the scattering is confined to a thin scattering
region located somewhat closer to the Earth than to the pulsars. Observations
of the system have been continued over a year and modulation of the
scintillation by the Earth's orbital velocity has been detected. This provides an
independent confirmation of the earlier results and a much more accurate
measurement of the center of mass velocity.




  34
    On the stationary phase point method in treating the
     transitional scattering of interstellar scintillation of
                            pulsars and IDVs
                        Chengmin Zhang, D.B. Melrose

In this report, we present the stationary phase point theory to calculate the
modulation index of the spectrum intensity when radio propagating in the
interstellar medium. From weak scattering to transitional scattering, about one
(N=1) and two (N=2) stationary phase points are taken into account, which
corresponds to the radio frequencies from 1 to 10 GHz. The influences by the
inner scale and outer scale of ISM turbulence on the scintillation are
investigated. Our conclusions include: from weak scattering, via transitional
scattering, to strong scattering, the spectrum modulation index increases and
then saturates with increasing the scattering strength characterized by the
ratio of Frenel scale $\rf$ to the diffractive scale $\rdiff$. Application of the
theory to the radio observations of pulsars and IDVs is discussed.




                                                                            35
           Galactic magnetic field probed by pulsars
              JinLin Han, R.N. Manchester, G.J. Qiao, A.G. Lyne

Review the progress for the pulsar rotation measure observations and the
application for the Galactic magnetic fields. Old models as well as the new
results of the Galactic structure of magnetic fields will dicussed.




  36
              Probing pulsar DMs using the GMRT
       Amrit Lal Ahuja, Yashwant Gupta, Dipanjan Mitra, Ajit Kembhavi

We present the results from a new experiment for accurate estimation of
pulsar dispersion measures (DM) using the Giant Meter-wave Radio
Telescope (GMRT). The observations were carried out over a period of more
than one year, scheduled once every fortnight, for a sample of twelve pulsars.
We have used the simultaneous multi-frequency capability of the GMRT to
obtain individual epoch DMs with an accuracy of 1 part in 10000 or better,
without requiring any absolute timing information. The important results from
our work are: (i) Most of the pulsars studied show DM variations on time
scales of weeks to months, which are likely to be due to the fluctuation of the
electron density in the ISM. (ii) The mean DM value for some of the pulsars
shows a significant discrepancy with respect to the catalog value (as well as
from other estimates in the literature), with the maximum difference occurring
for PSR B1642-03. (iii) Pulsar B2217+47 shows a large-scale DM gradient
over a one year period, which may be due to a blob of enhanced electron
density along the line of sight. (iv) For some pulsars we find small differences
in the DM values obtained from different frequency combinations. With the
help of numerical simulations, we show that in some cases, this may be due to
profile evolution with frequency; however, in other cases where the profile is
relatively simple (e.g. PSR B1642-03), alternative explanations such as
frequency dependent emission heights and magnetospheric plasma may play
a role.




                                                                           37
Two-component interstellar model in direction to the Vela
                                     pulsar
                        A. Z. Zhou, A. Esamdin, X. J. Wu

This paper discusses a rigorous treatment of the refractive scintillation of
pulsar PSR B0833-45 caused by a two-component interstellar scattering
medium. It is assumed that the interstellar scattering medium is composed of a
thin screen ISM and an extended interstellar medium. We consider that the
scattering of the thin screen concentrates in a thin layer presented by a
$\delta$ function distribution and that the scattering density of the extended
irregular medium satisfies the Gaussian distribution. We investigate and
develop equations for the flux density structure function corresponding to this
two-component ISM geometry in the scattering density distribution and
compare our result with that of the Vela pulsar observations. We conclude that
the refractive scintillation caused by this two-component ISM scattering gives
a more satisfactory explanation for the observed flux density variation of the
Vela pulsar than does the single extended medium model. The level of
refractive scintillation is strongly sensitive to the distribution of scattering
material along the line of sight. The logarithmic slope of the structure function
is sensitive to thin screen location and is relatively insensitive to the scattering
strength of the thin screen medium. Therefore, the proposed model can be
applied to interpret the structure function of flux density observed in pulsar
PSR B0833-45. The result suggests that the medium consists of a
discontinuous distribution of plasma turbulence embedded in the Vela
supernova remnant. Thus our work provides some insight into the distribution
of the scattering along the line of sight to the Vela pulsar.




   38
The distance to the Perseus spiral arm
   Xingwu Zheng, Y.Xu, M.J.Reid,K.M.Menten




                                             39
 Towards understanding non-RVM position angle curves
                                in pulsars
             Dipanjan Mitra, Yashwant Gupta (NCRA, Pune, India)

The classical `S-shaped' polarization position angle (PPA) traverses seen in
pulsars have long been understood under the rotating vector model (RVM) as
emission originating from dipolar magnetic field lines in the pulsar
magnetosphere. However significant number of pulsars show PPA traverses
which are distinct deviations from the RVM model. These can be classified in
two categories: (i) cases where the PPA's across the pulse show orthogonal
polarization modes and the individual modes follow the classical `S-shaped'
PPA traverse and (ii) cases where the PPA traverses show non-orthogonal
features which are distinctly different from the smoothly varying `S-shaped'
curve -- we refer to these as non-RVM PPA traverses. In this talk our attempt
will be to summarize the various non-RVM PPA traverse characteristics seen
in pulsars. Further we will argue that at least in some cases, by appropriately
choosing the emission heights across the emitting regions of the polar cap, we
can explain some of the non-RVM features seen in pulsars.




  40
    Dissipation of low-frequency waves in pulsar winds
                               Qinghuan Luo

Observations of pulsar wind nebulae (PWNe) strongly suggest that the wind is
predominantly in Poynting flux and becomes kinetic-energy dominated before
the termination shock. I will discuss the relevant low-frequency waves whose
dissipation may be responsible for such energy conversion. It is suggested
that the existence of large amplitude waves in the pulsar wind may be tested
by detection of coherent radio emission due to nonlinear Compton scattering.




                                                                       41
                Phenomenon of drifting subpulses
                      Janusz Gil, G. Melikidze, B. Zhang

Phenomenon of drifting subpulses in pulsars is discussed in terms of $E \times
B$ plasma drift model within a sparking gap scenario. It is shown that the
signatures of drifting subpulses detected in X-rays should be related to those
observed in radio wavelenghts. The corresponding relationship is applied to
PSR B0943+10, for which XMM-Newton observations were recently
performed. It is argued that the observational data are consistent with the
partially shielded polar gap by thermionic emission due to spark heating of the
polar cap. Some other pulsars with drifting subpulses are also discussed.




  42
  Pulse intensity distribution in the emission zone of PSR
                                B0950+08
                              Tatiana Smirnova

We carried out the analysis of individual pulses behavior at frequency 110
MHz on the base of two series of observation. We investigated the intensity
distribution of pulses in the emission zone of PSR B0950+08. The flux density
of the average pulse changes up to 10 times from day to day. It is a
consequence of scintillation effect. The intensity of individual pulses can
exceed in tens times of the average profile amplitude. It was shown that
intensity distribution of weak pulses in dependence of longitude of their
appearance in the emission zone differs strongly from distribution of strong
pulses. We also studied the evolution of the mean profile with a frequency in
the range from 110 MHz till 4.85 GHz. This work was supported by NSF grant
No. AST 0098685, the Russian Foundation for Basic Research: project codes
03-02-16509, 03-02-16522




                                                                        43
        Statistics on the drifting subpulse phenomenon
            Patrick Weltevrede, Russell Edwards and Ben Stappers

We present the results of a systematic, unbiased search for subpulse
modulation of 187 pulsars performed with the Westerbork Synthesis Radio
Telescope (WSRT) in the Netherlands at an observing wavelength of 21 cm.
Using new observations and archival WSRT data we have expanded the list of
pulsars which show the drifting subpulse phenomenon significantly, indicating
that at least one in three pulsars exhibits this phenomenon. The large number
of new drifters we have found allows us, for the first time, to do meaningful
statistics on the drifting phenomenon. We find that the drifting phenomenon is
correlated with the pulsar age such that drifting is more likely to occur in older
pulsars. Pulsars which drift more coherently seem to be older and have a
lower modulation index. There is no significant correlation found between
$P_3$ and other pulsar parameters (such as the pulsar age), as has been
reported in the past. There is no significant preference of drift direction and the
drift direction is not found to be correlated with pulsar parameters. The set of
modulation indices of our sample of pulsars show significant anti-correlations
with the four complexity parameters predicted by different emission models as
derived by \cite{jg03}. Therefore none of the models can be ruled out based on
our observations. We also present results on some interesting new individual
sources like a pulsar which shows similar subpulse modulation in both the
main- and interpulse and six pulsars with opposite drift senses in different
components.




   44
 Seeing triple - polarized views of the drifting subpulse
                               phenomenon
                         Russell Edwards, B. Stappers

It is presently in vogue to interpret drifting subpulse patterns in terms of
spatio-temporal modulation arising from a ring of "sparks" on the polar cap,
giving rise to a rotating "carousel"-type beam pattern. This model, in
conjunction with the standard scenario of plasma flow along, and radiation
tangential to dipole magnetic field lines, makes very specific predictions about
the variation in the phase of temporal modulation across the pulse window.
Recently attempts have been made to compare these predictions with
observational results. It is found that actual drifting subpulse patterns deviate
strongly from model predictions, and in fact offer some evidence for multiple
imaging of polar cap patterns by the magnetosphere, in a
polarization-dependent manner. I suggest that attempts to invert observations
to form "maps" of polar cap are fraught with peril unless the complicated
effects of the magnetosphere can be adequately unraveled.




                                                                            45
            The drifting subpulses of PSR B0031-07
                      Roy Smits, D. Mitra, J. Kuijpers

The well known drifter PSR B0031-07 is known to exhibit drifting subpulses
where the spacing between the drift bands (P3) shows three distinct modes A,
B and C corresponding to 12, 6 and 4 seconds respectively. We found that
mode A occurs simultaneously at both low (328 MHz) and high (4.85 GHz)
frequencies, while modes B and C only occur at low frequencies. However,
when the pulsar is emitting in mode B at the lower frequency there is still
emission at the higher frequency, hinting towards the presence of mode B
emission at a weaker level. Further, we have established that modes A and B
are associated with two orthogonal modes of polarisation, respectively.




  46
 Observational constraints on the emission region of PSR
                                 B1055-52
                Hongguang Wang, Qiao,G.J., Xu R.X. & Liu, Y.

The radio and $\gamma$-ray emission regions of PSR B1055$-$52 are
constrained via analyzing the observed radio and gamma-ray emission
properties. It is found that: (1) The radio main and the $\gamma$-ray pulses
are emitted from the same pole, while the radio inter-pulse is emitted from the
opposite pole. (2) The inter-pulse emission region locates on the open field
lines much closer to the agnetic axis than those of the main pulse, and the
emission altitudes are higher than those of the main pulse. (3) The
$\gamma$-ray pulse comes from inner open field lines rather than from the
last open field lines, and the emission altitudes are beyond the null charge
surface.




                                                                          47
               Giant pulses from millisecond pulsars
       Haydon Knight, M. Bailes, R. N. Manchester, S. M. Ord, B. A. Jacoby

Giant pulses from millisecond pulsars are a rare and poorly understood
phenomenon.In this talk I will summarise the properties of the three
millisecond pulsars previously known to emit giant pulses, and present new
evidence for giant pulse emission from two further millisecond pulsars.With a
larger population of emitters, I will argue giant pulses should not be defined
through high energies, but through their short timescales,power-law energy
statistics, and the narrow phase windows that they areemitted over.




  48
           Giant pulses of the pulsars radio emission
                               Arkady Kuzmin

Giant pulses (GPs) are short-duration outbursts of pulsar radio emission, a
rare phenomenon observed only in nine pulsars. The energy of GPs exceeds
the energy of the average pulse by more than factor of hundred. We present
the review report (may be presented as an invited talk) of this phenomenon,
based on our detection of three new pulsars with GPs, which belong to the first
group of pulsars found to have with GPs without a high magnetic field at the
light cylinder, and the comparative analysis of the previously known GPs
including the Crab pulsar and millisecond pulsar PSR B1937+21.




                                                                          49
              Origin of giant pulses in radio pulsars
                                Svetlana Petrova

Formation of giant radio pulses is attributed to propagation effects in the
plasma of pulsar magnetosphere. Induced scattering of radio waves by the
plasma particles is found to lead to an efficient redistribution of the radio
emission in frequency. With the steep spectrum of pulsar radiation, intensity
transfer between the widely spaced frequencies may imply significant
narrow-band amplification of the radiation. This is believed to underlie giant
pulse formation. It is demonstrated that the statistics of giant pulse intensities
observed can be reproduced if one take into account pulse-to-pulse
fluctuations of the plasma number density and original intensity. Polarization
properties of the strongly amplified pulses, their location in the average pulse
window and the origin of the nanostructure of giant pulses are discussed as
well.




   50
              What is special about high-B pulsars?
                   Natasa Vranesevic, Richard Manshester

The Parkes multibeam survey led to the identification of a number of
long-period pulsars with magnetic field well above the ``quantum critical field''
of ~4.4 x 10 to 13 G. Traditional pulsar emission theories postulated that radio
emission is suppressed above this critical field. The aims of this project is to
understand emission properties of high-B pulsars. In this presentation we will
show results on radio emission characteristic from high magnetic field pulsars
and emphasized their differences from normal pulsars.




                                                                            51
               A new aspect of pulsar radio spectra
                   Jaroslaw Kijak, Y. Gupta, K. Krzeszowski

The peak frequency is the frequency of the maximum flux where pulsars show
a decrease of the emitted energy at low frequencies (so called turnover).
Recent observations at low frequencies using GMRT Radiotelescope have
revealed interesting features in pulsar spectra. Spectra of several pulsars with
the peak at unusually high frequencies (about 1 GHz) are presented. We
report that the peak frequency in pulsar spectra depends on dispersion
measure DM.




  52
     Evidence for alignment of the rotation and velocity
                            vectors in pulsars
         Simon Johnston, Hobbs, Vigeland, Kramer, Wesiberg, Lyne

We present observational data showing evidence for a relationship between
the direction of a pulsar's motion and its rotation axis and conclude that the
velocity vector and the rotation axis are aligned at birth. We discuss the
implications of these findings in the context of kick models.




                                                                           53
 Spin, Magnetism and Velocities of Young Neutron Stars
                                   Dong Lai

I will discuss our current knowledge of the spin, magnetic fields and velocities
of neutron stars, and the physics behind them.




  54
          Pulsar glitches in the Jodrell glitch database
                      Ali Esamdin, A. G. Lyne, M. Kremer

We present the results of the recent updating of the Jodrell Glitch Database.
According to the Database, about 189 glitches have been detected so far.
Increase in the number of pulsar glitches will improve our statistical analysis of
glitch phenomena, refining existing glitch models and inspiring an
understanding of the neutron star interiors.




                                                                             55
         Radio emission of anomalous X-ray pulsars
                   Valery Malofeev, Malov O., Teplykh D.

Anomalous X-ray pulsars (AXPs) are small group (5-7 objects) of exotic young
neutron stars and about half of them are coincident with supernova remnants.
We present the detection and new data on radio emission of two AXPs:
1E2259+586 and 1RXS J130848.6+212708. The observations were perfomed
using two sensitive transit radio telescopes in Pushchino (Russia) at
frequencies 111, 88, 61 and 42 MHz. The pulse profiles, the flux density and
the dispersion measure are presented, as well as, the estimations of the
distance and the integral luminosity. The barycentric periods and period
derivatives during the interval 3 and 2 years have been conculated. The
comparison of our and X-ray data showed the presence of large difference in
the width of mean profiles and the luminosity.




  56
   The same physics underlying SGRs, AXPs, and radio
                                  pulsars
                                 Biping Gong

Unexpected sign, significant magnitude and time-variation of frequency
second derivative exist not only in singular radio pulsars but also in Soft
Gamma repeaters (SGRs) and Anomalous X-ray pulsars (AXPs). This paper
shows that the these phenomena are related, and can be interpreted by a
simple unified model, long-term orbital effect. Thus many of previous
``singular'' pulsars may be binary pulsars with very small companion mass,
i.e., orbital period $P_b\approx22$min for SGR 1900+14,
$P_b\approx0.21$day for AXP 1E 2259+586, and $P_b\approx1.5$hr for PSR
J1614-5047. There might be more binary pulsars than we had thought about,
and the number of binary pulsars that suitable for gravitational wave detection
may also increase.




                                                                          57
                        Nature of "magnetars"
                           Igor Malov, G.Z.Machabeli

A brief review of known models for the description of Anomalous X-ray Pulsars
(AXPs) and Soft Gamma-Repeaters (SGRs) is given. A new model is
proposed to explain the main properties of these objects on the base of the
conception of drift waves in the vicinity of the light cylinder of the neutron star
with the surface magnetic field ~10^12 G. In the framework of this model
rotation periods P, their derivatives dP/dt and magnetic fields B in the regions
of generation of emission observed in AXPs and SGRs are calculated. The
intervals for these parameters are P = 11 – 737 msec, dP/dt = 3.7 x 10^(-16) –
5.5 x 10^(-12), log B = 2.63 – 6.25. A modulation with periods P can be
observed in sources under consideration. A strong relationship between the
pulsed X-ray luminosity L of AXP and SGR and the rate of their rotation energy
losses dE/dt is detected. It coincides with the dependence Lx (dE/dt) for radio
pulsars with detected X-ray radiation. Slopes of the relationships log (dP/dt) –
logP and log η –logP for AXPs and SGRs and for radio pulsars with short
periods (P < 0.1 sec) are equal each other ( η is the efficiency of a
transformation of the rotation energy into radiation). Magnetic fields at the
neutron star surface calculated in the framework of the dipole model for AXPs
and SGRs have the same order ( = 11.90) as for normal radio pulsars. It is
shown that cyclotron radiation of electrons near the surface of a neutron star
with magnetic field ~ 10^12 G gives the possibility to explain the observed
quiescent X-ray emission of AXPs and SGRs. The pulsed emission is
generated by the synchrotron mechanism near the light cylinder. Cataclysms
on the neutron star can cause short gamma-ray bursts with a power exceeding
the X-ray power 2 g^2 times. Here g is the Lorentz-factor of emitting electrons.
It is shown that in the “magnetar” model the electron cyclotron line with the
energy ~ 1 MeV must be formed. Its detection will be a good evidence for this
model. It is shown that the drift waves near the light cylinder can cause the
modulation of emission with periods of order several seconds in radio pulsars
as well. These periods explains the intervals between successive pulses
observed in radio pulsars with long periods ( P > 5 s). The model under
consideration gives the possibility to calculate real rotation periods of host
neutron stars. They are less than 1 sec for the investigated objects. The
magnetic fields at the surface of the neutron star are of order 10^11 – 10^13 G
and equal to the fields usual for normal radio pulsars. Pulsars of such types
must have short periods ( P ≲ 0.1 sec) and the small angle β between rotation
and magnetic axes (β < 10 degrees). It is expected that the part of these
pulsars in the all pulsar population must be of order 0.01. This estimate is in a
good agreement with the known number of AXPs, SGRs and radio pulsars
with very long periods.

   58
59
                       Pulsars and quark stars
                                  Renxin Xu

Members of the family of pulsar-like stars are distinguished by their different
manifestations observed, i.e., radio pulsars, X-ray pulsars, X-ray bursts,
anomalous X-ray pulsars/soft gamma-ray repeaters, compact center objects,
and dim thermal neutron stars. Though one may conventionally think that
these stars are normal neutron stars, it is still an open issue whether they are
actually neutron stars or quark stars, as no convincing work, either theoretical
from first principles or observational, has confirmed Baade–Zwicky's original
idea that supernovae produce neutron stars. Quark matter (or quark-gluon
plasma) is a direct consequence of the asymptotic freedom, proven in 1973
with non-abelian gauge theories, and it could be a shortcut to detect
astrophysical quark matte in order to probe into the elementary color
interaction. Quark stars are made of quark matter with low temperature and
high baryon density. Observations challenging the conventional neutron stars
models are presented, which might be naturally understood by updating
neutron star models with quark star models. Various properties of quark matter
are introduced phenomenologically, including the X-ray thermal radiation, the
shear modulus of possible solid state, and the stellar mass distribution in
reality. More future observations, which may result in a clear identification of
quark stars, are predicted.




  60
                  The origin of glitches of pulsars
                                  Qiu-he Peng

It is particularly interesting to note that the period of the pulsar at this stage
may be decrease suddenly especially for some young pulsars (for instance,
the Vela pulsar and Crab pulsar) and then followed by a gradual recovery. This
is known in the literature as pulsar glitch. In our neutron superfluid vortex
model, pulsar glitch may be explained very naturally and qualitatively on the
basis of the phase oscillation between the normal fermi fluid phase of neutrons
with the 3p2 superfluid vortex phase of neutrons at the phase transition
temperature, Ttrans=Δn(3p2)/k≈(4~5)×108K where Δn(3p2)≈(0.04~0.05)MeV
(Elgaøy et al. 1996) at the density in the outer core. The idea is following: The
3
 p2 superfluid vortex phase of neutrons occurs when the neutron interior
temperature decrease down below Ttrans , the angular momentum of the
neutron superfluid vortexes are transformed from that of the primordial highly
turbulent classical vortexes. No influence on the rotation rate of the crust can
be detectable during this phase transition. But the neutrons of the 3p2
superfluid vortexes with high initial quantum number will radiate strong X-ray
due to their magnetic dipole radiation from the fast rotating neutrons in the
vortexes (Huang et al. 1982). The emitted x-ray will be absorbed by the interior
electrons and will heat the interior of the neutron star. The temperature will
increase as long as the power of the X-ray radiation is strong enough to
surpass the cooling rate of the neutron star owing to some cooling
mechanisms. Hence, the 3p2 superfluid vortexes will disappear immediately
when the temperature increase above the phase transition temperature. The
neutron system recovers the normal Fermi fluid state again. The released
angular momentum of the neutrons of the quantum vortexes is assumed to
transform into the angular momentum of crust with the core of the neutron star
(but the 1S0 neutron superfluid and the proton superconductor are weakly
couple with the crust, they will be influenced after glitch). Therefore, the crust
will be suddenly spin up to make the glitch phenomena. The phase oscillation
and the resulting glitch will be repeatedly occur or recurrent.




                                                                             61
       Pulsar timing observations at Urumqi Observatory
                                  Weizhen Zou

We report the status and results of pulsar timing observations at Urumqi
Observatory. Observations for 74 radio pulsars were made regularly at 1540
MHz as part of the Urumqi Observatory timing program, which commenced in
1999 at the 25-m Urumqi Nanshan telescope. Currently approximately 280
pulsars are monitored with an average interval between observations of
approximately 9 days. The dedispersion is provided by a 2×128×2.5 MHz
filterbank/digitiser system. We obtained the updated periods and period
derivatives for 74 pulsars with timing observations of one year, and
observations over more than four years have resulted in improved positions,
proper motions and velocities for these 74 pulsars. Comparing with earlier
observations we showed that long-term period and period-derivative
fluctuations may be dominated by unseen glitches. We also present the
observed results for ten glitches of four young pulsars detected in the last five
years.




  62
           Rotational evolution of protoneutron stars
                           Yefei Yuan, Jeremy Heyl

We study the evolution of a rigidly rotating protoneutron star with hyperons
and nucleons or solely nucleons in its core due to the escape of the trapped
neutrinos. As the neutrinos escape, the core nucleonic neutron star expands
and the stellar rotation slows. After the neutrinos escape, the range of the spin
periods is narrower than the initial one, but the distribution is still nearly
uniform. A protoneutron star with hyperons, at the late stage of its evolution,
keeps shrinking and spinning up until all the trapped neutrinos escape.
Consequently, the distribution of the stellar initial spin periods is skewed
toward shorter periods. If the hyperonic star is metastable, its rotational
frequency accelerates distinguishedly before it collapses to a black hole.




                                                                            63
 Millisecond pulsar population in the Galactic center and
                     high energy contributions
                                 Wei Wang

We propose that there possibly exists a population of millisecond pulsars in
the Galactic center region. Millisecond pulsars could emit GeV gamma-rays
through synchrotron-curvature radiation as predicted by outer gap models. In
the same time, the compact wind nebulae around millisecond pulsars can emit
X-rays though synchrotron radiation and TeV photons through inverse
Compton processes. In addition, the millisecond pulsar winds provide good
candidates for the electron-positrons sources in the Galactic center.
Therefore, we suggest that the millisecond pulsar population could contribute
to the weak unidentified Chandra X-ray sources, the diffuse gamma-rays
detected by EGRET, electron-positron annihilation lines and possible TeV
photons detected by HESS toward the Galactic center.




  64
 Radio pulsars as progenitors of anomalous x-ray pulsars
  and soft gamma-ray repeaters: magnetic field evolution
                        through pulsar glitches
                       Shuang Nan Zhang, Jinrong Lin

Glitches are common phenomena in pulsars. After each glitch, there is often a
permanent increase in the pulsar's spin-down rate. Therefore, a pulsar's
present spin-down rate may be much higher than its initial value and the
characteristic age of a pulsar based on its present spin-down rate and period
may be shorter than its true age. At the same time, the permanent increase of
its spin-down rate implies that the pulsar's surface magnetic field is increased
after each glitch. Consequently, after many glitches some radio pulsars may
evolve into magnetars, i.e., strongly magnetized and slowly rotating neutron
stars.




                                                                           65
          Pulsar observation with the telescope FAST
                                  Rendong Nan

FAST, Five hundred meter Aperture Spherical Telescope, is the Chinese effort
for the international project SKA, Square Kilometer Array. The innovative
engineering concept and design pave a new road to realizing huge single dish
in the most effective way. Three outstanding features of the telescope are the
unique karst depressions as the sites, the active main reflector which corrects
spherical aberration on the ground to achieve full polarization and wide band
without involving complex feed system, and the light focus cabin driven by
cables and servomechanism plus a parallel robot as secondary adjustable
system to carry the most precise parts of the receivers. Being the most
sensitive radio telescope, FAST will enable astronomers to jumpstart many of
science goals, for example, the natural hydrogen line surveying in distant
galaxies out to red-shift around 3, looking for the first star shining, hearing the
possible signal from other civilizations and etc. Among these subjects, the
most striking one could be surveying new pulsars. Extremely interesting and
exotic objects may yet wait for discovery by the FAST as the telescope is put
into operation.




   66
     Pulsar science with the GMRT : achievements and
                                   prospects
                                 Yashwant Gupta

The GMRT is emerging as a powerful new instrument for studies of radio
pulsars. In this talk, I will highlight the unique selling points of the GMRT in this
context and then go on to describe some of the important recent results from
the GMRT in the field of pulsars. These cover diverse topics like (i) discoveries
of new pulsars (ii) detailed studies of emission properties from average profile
and single pulse observations (iii) probing the properties of the ISM using
pulsars and (iv) results from simultaneous multi-frequency observations. I will
also describe some of the ongoing and planned programs.




                                                                                67
              Arecibo and the ALFA pulsar survey
                   Joeri van Leeuwen, The ALFA consortium

I will report results from the initial stage of a long-term pulsar survey of the
Galactic plane using the Arecibo L-band Feed Array (ALFA), a seven-beam
receiver operating at 1.4GHz with 0.3GHz bandwidth,and fast-dump digital
spectrometers. With our preliminary, low-resolution analysis we have
discovered more than 10 new pulsars. One of these is a young pulsar in a
relativistic binary with an orbital period of only 3.98hr. Over the next few years
we expect to find around 1000 new radio pulsars in total.




   68
             The Miyun 50m pulsar radio telescope
                                 Chengjin Jin

We will give an introduction to the Miyun 50m pulsar radio telescope. The
technical specs and the current status of construction of the telescope and the
pulsar receiver will be presented. The 50m radio telescope, together with the
pular receiver, will make a powerful pulsar radio telescope.




                                                                          69
 How might LOFAR and SKA impact pulsar astronomy?
                                  Richard Strom

Several future large telescope projects are at present characterized by rather
general instrumental properties. Concepts of the Square Kilometer Array
(SKA) range from huge numbers of small elements to 100 or fewer large-area
concentrators. The single unifying characteristic is an effective collecting area
of about one square kilometer. The history of SKA will be briefly reviewed, in
particular the considerations which led to its present conception. Although not
specifically designed for pulsar astronomy, it is clear that such a quantum leap
in sensitivity will impact this area of research, and some of the possibilities will
be noted. The Low Frequency Array (LOFAR) is a project to build a large-area
telescope operating over a broad range of frequencies below 250 MHz. The
present state of the project, including antenna design, array geometry and
scientific goals will be discussed. LOFAR will not only serve astronomy, but
also has applications in disciplines ranging from cosmic rays to agriculture,
and these (as well as their rationale) will also be considered. Some of its uses
in pulsar research will be reviewed.




   70
     Evidence for alignment of the rotation and velocity
                            vectors in pulsars
         Simon Johnston, Hobbs, Vigeland, Kramer, Wesiberg, Lyne

We present observational data showing evidence for a relationship between
the direction of a pulsar's motion and its rotation axis and conclude that the
velocity vector and the rotation axis are aligned at birth. We discuss the
implications of these findings in the context of kick models.




                                                                           71
72
                                      POSTERS

Probing pulsar DMs using the GMRT
Amrit Lal Ahuja, Yashwant Gupta, Dipanjan Mitra, Ajit Kembhavi


We present the results from a new experiment for accurate estimation of pulsar dispersion measures (DM)
using the Giant Meter-wave Radio Telescope (GMRT). The observations were carried out over a period of
more than one year, scheduled once every fortnight, for a sample of twelve pulsars. We have used the
simultaneous multi-frequency capability of the GMRT to obtain individual epoch DMs with an accuracy
of 1 part in 10000 or better, without requiring any absolute timing information. The important results from
our work are: (i) Most of the pulsars studied show DM variations on time scales of weeks to months,
which are likely to be due to the fluctuation of the electron density in the ISM. (ii) The mean DM value
for some of the pulsars shows a significant discrepancy with respect to the catalog value (as well as from
other estimates in the literature), with the maximum difference occurring for PSR B1642-03. (iii) Pulsar
B2217+47 shows a large-scale DM gradient over a one year period, which may be due to a blob of
enhanced electron density along the line of sight. (iv) For some pulsars we find small differences in the
DM values obtained from different frequency combinations. With the help of numerical simulations, we
show that in some cases, this may be due to profile evolution with frequency; however, in other cases
where the profile is relatively simple (e.g. PSR B1642-03), alternative explanations such as frequency
dependent emission heights and magnetospheric plasma may play a role.




                                                                                                    73
R-process nucleosynthesis responsible for the pulsar formation and its

timing
Rulee Baruah, Kalpana Duorah


We have studied the nucleosynthesis process namely r-process responsible for the synthesis of heavy
nuclei beyond iron.Dynamical events like supernovae are recognised as one of the most probable sites for
the r-process.As pulsars are rotating neutron stars which appear in supernova remnants, we tried to put
some new light in pulsar timing from supernova collapse time.We have studied the collapse time
corresponding to temperatures ranging from 1.5x10^9 K to 12x10^9 K and neutron number density
ranging from 10^24 cm^-3 to 10^32 cm^-3.As the neutron number density increases the collapse time is
found to be significant enough for the production of neutron stars and correspondingly pulsars.




Timing Noise in HartRAO Pulsars
Sarah Buchner, C Flanagan, F Frescura


I will present results of an investigation into the timing noise of the HartRAO pulsar observations.




   74
A self-adaptive connector for active main spherical reflector of FAST
Yi Chen, YuangenQu,JianingWang


A new kind of position control system for basic elements of sphere is introduced in the paper. Based on
mechanical principle, structure analysis is made for the control system, which proved that it meets special
need of the position control system of FAST. In addition , kinematics analysis is made for the
compensation fit of the system and compensating size is calculated . Lastly , some results of experiment
are given.




The Current Flows in Pulsar Magnetospheres
Xiaohong Cui, Ren-Xin Xu, Guo-Jun Qiao


The global structure of the current flows in pulsar magnetospheres is investigated, with rough calculations
of the elements in the magnetospheric circuit. It is emphasized that the potential of critical field lines is the
same as that of interstellar medium, and that the pulsars whose rotation axes and magnetic dipole axes are
parallel should be positively charged, in order to close the pulsar's current flows. The statistical relation
between the radio luminosity and pulsar's electric charge (or the spindown power) may hint that the
millisecond pulsars could be low-mass bare strange stars.




                                                                                                          75
Search radio pulsar in 3EG sources
Jiang Dong, Na Wang


We use 25m radio telescope of Urumqi Observatory find pulsar in 3EG sources .




Detection of Giant Pulses in Pulsar PSR J1752+2359
Alexander Ershov, A.D. Kuzmin


Giant pulses (GPs) are short duration burst-like increases of an intensity of individual pulses from pulsars.
The detection and first searches of GPs were performed in pulsars with extremely high magnetic field at
the light cylinder of B_{LC} = 10^4 - 10^5 G. In this talk we report the detection of GPs in the pulsar PSR
J1752+2359 with relatively low magnetic field at the light cylinder. Observations were performed with the
Large Phase Array (BSA) Radio Telescope (Pushchino RadioAstronomy Observatory) at a frequency of
111 MHz. One linear polarization was received. We used a 128-channel receiver with channel bandwidth
20 kHz. The sampling interval was 2.56 ms. The duration of each observation session was about 3 min
(420 pulsar periods). A total of 120 observations containing 50,400 pulsar periods were carried out. The
187 pulses (1 pulse for 270 observed periods) with S/N > 5 were selected and analyzed. About one pulse
in 270 has peak flux density more than 40 times the peak flux density of an average pulse, and the
strongest GP as large as 260. A pulse whose energy exceeded an energy of the average pulse by more than
a factor of 100 is encountered approximately once in 3000 observed periods. The energy of the strongest
GP exceeds the energy of the average pulse by a factor of 200 in which it stands out from other pulsars
with GPs. The cumulative intensity distribution is fit by a power-law dependence with index -3.0+/-0.4.
PSR J1752+2359 as well as the previously detected PSR B0031--07 and PSR B1112+50, belongs to the
group of pulsars found to have GPs without a high magnetic field at the light cylinder.




   76
Polarizations in blazars
J.H. Fan, Fang, Liu, Yong-Xiong Wang


High and variable polarization is one of the typical characteristic properties of blazars. It was found that
the polarization is associated with the beaming efffect.




Developing radio beam geometry and luminosity models of pulsars
Peter Gonthier, S.A. Story, B.M. Giacherio, R.A. Arevalo and A.K. Harding


Our recent studies of pulsar population statistics suggest that improvements of radio and gamma-ray beam
geometry and luminosity models require further refinement. The polarization properties of radio profiles
of gamma-ray pulsars do not suggest that short period pulsars are core dominated, as discussed by the
study of Arzoumanian, Chernoff & Cordes (2002). Furthermore, the predicted radio luminosity in this
model seems to be too large compared to those observed. The goal of this project is to constrain the
viewing geometry for some radio pulsars, especially three-peaked pulse profiles, in order to limit the
uncertainty of the magnetic inclination and impact angles. We perform fits of the pulse profile and
position angle sweep of radio pulsars for the available frequencies. We assume a single core and conal
beams described by Gaussians. We incorporate three different size cones with frequency dependence from
the work of Mitra and Deshpande (1999). We obtain separate spectral indices for the core and cone beams
and explore the trends of the ratio of core to cone peak fluxes. This ratio is observed to have some
dependence with period. However, we cannot establish the suggested functional form of this ratio as
indicated by the work of Arzoumanian, Chernoff & Cordes (2002). We will present our current findings
and implications.




                                                                                                     77
TEMPO2: Software for a new era of precision pulsar timing
George Hobbs, R. Edwards, R. Manchester


TEMPO2 is a new pulsar timing package that implements all relevant timing corrections to an accuracy of
1 ns or better. In contrast with earlier timing packages, TEMPO2 is compliant with the IAU 2000
resolutions and hence uses up-to-date precession and nutation models, the International Celestial
Reference System and Barycentric Coordinate Time. TEMPO2 allows the analysis of multiple pulsars
simultaneously which is necessary when looking for global signatures that are common between pulsars.
The software also includes numerous visualisation and analysis tools. TEMPO2 will supersede all existing
pulsar timing packages and provide the accuracy needed for pulsar timing into and beyond the SKA era.




Can giant pulses be used to probe quantum gravity?
Haydon Knight




   78
Fallback Disk Involved Spin-down of Young Radio Pulsars
Xiang-Dong Li, Zi-Bo Jiang


Disks originating from supernova fallback have been suggested to surround young neutron stars. The
interaction between the disks and neutron star magnetic fields may considerably influence the evolution of
neutron stars through the so called propeller effect. There are many controversies about the efficiency of
the propeller mechanisms proposed in the literature. In this paper we investigate the fallback disk involved
spin-down of young pulsars. By comparing the simulated results of pulsar evolution with the measured
ones, we present possible constraints on the propeller torques exerted by the disks on neutron stars.




Using MK5A to Implement Pulsar Coherent Dedispersion at UAO
Liyong Liu




                                                                                                     79
Deep impact on a neutron star
Xiang Liu


We analyze a double NS system, and give analytic solutions of deep impact each other in a double NS
system.




A model for the reversible radio emission in PSR B1822-09
George Melikidze, J.Gil, B.Zang


A model for PSR B1822-09 was recently proposed by Dyks, Zhang and Gil (ApJ, 2005, 626, L45), which
implies the reversals of radio emission direction to explain the MP and IP behavior. Here we propose the
model of generation of such coherent radio emission. The model is based on the resonant interaction of
plasma clouds, created by gamma rays radiated in inner and outer gaps.




   80
Does radius to frequency mapping exist for core emission in pulsars?
Dipanjan Mitra, Yashwant Gupta


The pulsar emission beam is thought to be in the form of nested cones with a centrally located core. There
are strong arguments that cone emission arises higher than core emission with respect to the neutron star's
surface; and further that the cone emission shows the distinct phenomenon of radius to frequency mapping
where cones at higher frequencies arise closer to the stellar surface. However there is very little known
about the location of the core emission with frequency. Using data of pulsars with multifrequency average
profiles having well identified core components, we show that a radius to frequency mapping like effect
might be operating in cores also. Further, based on analysis of single pulse data, we show that even at a
single frequency cores may be originating over a range of heights.




Propagation model of the individual pulse polarization
Svetlana Petrova


Polarization evolution of radio waves in the plasma of pulsar magnetosphere is considered. It is shown
that the original natural waves of the plasma, which are linearly polarized in orthogonal directions, acquire
elliptical polarization. Especial attention is paid to the polarization evolution in the region of cyclotron
resonance, where the waves become slightly non-orthogonal. A model of pulsar polarization is suggested
based on an idea of non-orthogonal superposed modes. It allows to reproduce the main features of the
observed single-pulse polarization. The implications of polarization data of individual pulses for
diagnostics of pulsar plasma will be outlined as well.




                                                                                                      81
A Search for ISS in the non-pulsing flux from the Double Pulsar

J0737-3039
Barney Rickett, Bill Coles


One of the intriguing aspects of the double pulsar is the report of 5 mJy of non-pulsing flux at 1.4 GHz,
presumed to be coming from this system. We have made a series of dynamic spectrum observations
centered near 1.8 GHz, which we have searched for interstellar scintillation (ISS) from the unpulsed
source. We will describe the techniques we have used to remove the large scale variations in flux density
over frequency and time - without the benefit the pulsar's periodic modulation. So far, we have not found
evidence for ISS in the non-pulsing source. Our result is a 2 mJy upper limit to the standard deviation in
fux density at 1.8 GHz. Comparing this with the source's mean flux density at 1.4 GHz, we conclude that
its scintillation index is less than 50%, which implies a source diameter of about 30,000 km or larger. This
limit is comparable to estimates of the radius of the magnetosphere of the slow pulsar, as compressed by
the wind from the fast pulsar. We will discuss the implications for the non-pulsing emission.




On the Inside and Outside Space-Time Character of the Rotating

Neutron Stars with the Disc
Burhan Salay


By deeply studying the Einstein’s rotating plate (ERP) problem, we get that the definition of the new
Einstein rotating plate (NERP). Using the new coordinate transformations to the rotating neutron stars,
and take account of the Einstein’s field equations and the thermo equilibrium condition, we get that the
natural inside and outside space-time structure of the rotating neutron stars with the disc. We also do some
discussion for it.




   82
Pulsars with Multiple Scintillation Arcs
Daniel R. Stinebring, M. Putney


Of the dozen or so pulsars that have been well studied for scintillation arcs, most show one arc only. This
is a puzzle, since if a sharply defined arc arises from scattering in a thin screen of material, it would be
surprising (i.e. not believable) if there was only one thin screen along each line of sight. I will show
evidence from three or four pulsars of multiple scintillation arcs and argue that multiple arcs are seen
when the sensitivity is high enough.




Scintillation and Pulsar Timing: Problems and Promise
Dan Stinebring and Dan Hemberger


The study of pulsar scintillation has undergone a revolution in the last few years with important
implications for highest precision pulsar timing. Dynamic spectra with very high frequency resolution and
high dynamic range have shown the ubiquitous presence of scattered ray paths that are delayed by many
times what might be expected from a temporal scattering profile analysis. These ray paths, scattered from
small-size inhomogeneities in the interstellar medium, make up a minor portion of the total flux density,
but their anomalously large delays can have a significant effect on highest precision timing.
Furthermore, the delay is time variable (on a several day to week scale) as the line of sight moves through
the interstellar medium. The good news is that techniques are emerging to precisely determine the total
interstellar scattering delay, including these anomalous ``halo'' delays, which should allow for a more
accurate correction of pulsar timing observations. I will explain this more fully and offer estimates of path
delays for some representative pulsar timing cases.




                                                                                                      83
Core-dominance parameters and the unification of BLs and FRI

radio sources
Yongxiang Wang, Yong-Xiong Wang, J.H. Fan, Juan Li


In this work, we used the core-dominance parameters to investigate the unification model and found that
BLs and FRI radio sources are the same originally.




Gamma-ray mature pulsars: unidentified EGRET sources, possible

TeV sources and radio detectivity
Wei Wang, Y. Zhao, Y. Lu


We study the $\gamma$-ray emission from the pulsar magnetosphere based on outer gap models, and the
TeV radiation from pulsar wind nebulae (PWNe) through inverse Compton scattering using a one-zone
model. We carry out Monte Carlo simulations of $\gamma$-ray pulsars in the Galaxy and the Gould Belt,
assuming values for the pulsar birth rate, initial position, proper motion velocity, period, and magnetic
field distribution and evolution based on observational statistics. We select from the simulation a sample
of 44 mature pulsars in the Galactic plane ($|b|\leq 5^\circ$) and a sample of 32 mature pulsars at high
latitudes ($|b|> 5^\circ$) which could be detected by EGRET. About 12 mature pulsar could be observed
in the radio band. The results showed that GeV radiation from the magnetosphere of mature pulsars can
contribute to the high latitude unidentified EGRET sources. The TeV fluxes from the pulsar wind nebulae
of our simulated sample produced through inverse Compton scattering by relativistic electrons on the
cosmic microwave background and synchrotron seed photons are calculated. We suggest that strong
EGRET sources may be potential TeV source candidates, and up to 15 sources could be detected by
present and future three-generation TeV telescopes if they are mature pulsars.




   84
Whether the old Neutron Stars are the source of Gama-Ray Bursts?
Xinji Wu




Long-term spectroscopic and near-infrared monitoring of Be/X-ray

binaries
Jingzhi Yan, Q.Z. Liu and H. R. Hang


More than 100 Be/X-ray binaries have been discovered up to now (see Liu, van Paradijs \& van den
Heuvel 2000). Since 1992, we have begun a long-term program to monitor the optical spectroscopic and
the near-infrared photometric variations of 13 Be/X-ray binaries and 34 Be stars. The object of this
program is to investigate the origin of Be phenomena by comparing the properties of the Be stars in
Be/X-ray binaries with those of other Be stars, and to learn more about the physical properties of the
circumstellar disc around Be stars. We present in this paper a summary of the long-term program for
Be/X-ray binaries. Some systems are re-identified to confirm their Be/X-ray binary nature, and several
particular sources and events are also discussed.




                                                                                                85
Flux-depended X-ray spectrum index of blazars
Jianghe Yang, Jun-hui Fan


A sample including 69 blazars was selected from a paper by Donato et al. (2001). Used the smple, the
relations between flux density and spectrum index, the distributions of redshift and spectrum index were
investigated for highly frequency peaked BL Lac (HBLs), lowly frequency peaked BL Lac (LBLs) and
flat spectrum radio quasars (FSRQs) respectively. Our results show that (1) an anti-correlation was found
for HBL, there is no clear relation for LBL or FSRQs, which suggest that the X-ray emission in HBLs are
from synchrotron process while that for LBLs and FSRQs from synchrotron self-Compton process, (2) the
X-ray spectrum index has a consequence for the three subclasses with HBLs showing the softest X-ray
spectrum and FSRQs the hardest X-ray spectrum with LBLs being between them, and (3) HBLs locate at
nearest while FSRQs the furthest with LBLs being between them.




To understand the UV-optical excess of RX J1856.5-3754
Youling Yue, R. X. Xu


The enigma source, RX J1856.5-3754, is one of the so-called dim thermal neutron stars. Two puzzles of
RXJ1856 exist: (1) the observational X-ray spectrum is completely featureless; (2) the UV-optical
intensity is about 7 times that given by the continuation of the blackbody model yielded by the X-ray data.
Both the puzzles would not exist anymore if RX J1856.5-3754 is a (probably low mass) bare strange star,
which is in a propeller phase with a low accretion rate. The boundary layer of RXJ1856.5-3754 is
modeled, from which the UV-optical emission is radiated. The X-ray emission is from the stellar surface.
The star's radius, spin period, as well as the accretion rate are constrained by observations.




   86
What do the rapidly spinning pulsars signal?
Xiaoping Zheng, Shuhua Yang, Nana Pan


The rapidly spinning pulsars would be regarded as a competition between gravitational wave emission and
viscous dissipation. All cases, neutron stars,strange stars and hybrid stars, have been discussed here. The
viscosity due to strangeness-changing weak interactions in dese nuclear matter fixes the fastest spinning
frequencies in the compact stars.This only implies the existence of strangeness either hyperon matter or
strange quark matter or their mixed phase in the ihterior of the stars. We conclude that the cluster of
rapidly spinning pulsars, which have two fastest millisecond pulsars and the low-mass x-ray binary, is
possible signal for the strangeness relevance.




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