A X-Ray Surveys

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A X-Ray Surveys Powered By Docstoc
					A     X-Ray Surveys
Time: Tuesday 4th April, 11.00
Location: Bennett 1
Chair: Gordon Stewart

A.1 The XMM-Newton spectroscopic survey of the 13H deep field
Dr Mat Page (Mullard Space Science Lab, UCL) - Oral presentation
N.S. Loaring, T. Dwelly, K.O. Mason, I. McHardy, K. Gunn, D. Moss, T.Sasseen, F. Cordova, J. Kennea, N.
We have constructed X-ray spectra for a sample of 86 optically-identified sources in the
13H XMM-Newton deep field with log F(2 − 10) between -15 and -13.5 cgs. The sample
consists of 50 broad-line AGN, 25 narrow emission line galaxies (NELGs), 6 absorption line
galaxies, and 5 Galactic stars. Unsurprisingly, most of the broad-line AGN have power law
spectra with no absorption, and more than half of the NELGs have absorbed X-ray spectra.
However, several of the broad line AGN show absorption, and quite a few (16) of the NELGs
and galaxies show do not. Combining the X-ray spectra with the other multi-wavelength
information we are able to determine:
    1) that almost all the NELGs and galaxies with X-ray luminosities between 1040 and 1042
cgs are AGN-powered - including those with soft spectra. Star formation thus powers a very
small fraction of the sources in X-ray surveys except at the very lowest luminosities (∼ 1040
cgs and lower).
    2) how at least some of the broad line AGN manage to have both photoelectric absorption
and broad emission lines.
    3) that the soft spectrum NELGs and galaxies are primarily AGN without obscuration,
but with host galaxies that outshine them in the optical, effectively hiding the AGN compo-

A.2 Science with the 2XMM serendipitous source catalogue
Mrs Silvia Mateos (University of Leicester) - Oral presentation
XMM-Newton Survey Science Centre
The XMM-Newton Survey Science Centre will soon release the second XMM-Newton
serendipitous source catalogue, 2XMM. This will be the largest X-ray source catalogue ever
made, including more than ∼150,000 objects from 4000 XMM-Newton observations since
launch and covering a total sky area of approximately 400 sq.deg. The typical flux limit of
the survey is ∼ 10−14 cgs (at 0.2-12 keV), well matched to the dominant source population of
the cosmic X-ray background emission (CXRB). The catalogue itself is also complemented
by X-ray spectra and light curves for the brighter objects in each field (around 10% of the
total catalogue).
    2XMM is set to become a unique astronomical resource to explore both the Galactic and
extragalactic X-ray source populations. The large area of the 2XMM catalogue maximises
the probablility of identifying the rarest and most extreme objects in the X-ray sky. In this
paper we will describe the 2XMM catalogue and highlight its scientific value, emphasising
how exploiting the full scientific potential of 2XMM will come from the crosscorrelation of
the catalogue with multi-wavelength archives.
A.3 The X-ray Galaxy Cluster Survey (XCS) and the most distant X-ray
Prof Chris Collins (Liverpool JMU) - Oral presentation
K. Romer 1 , R. Mann 2 , C. Miller 3 , A. Stanford 4 , M. Hilton 5 , R. Nichol 6 , M. West 7 , P. Viana 8 , A Liddle 1 ,
S Kay 9 , M Davidson 2 , K Sabirli 1,10 (1 University of Sussex, 2 IFA, Edinburgh, 3 NOAO/CTIO, 4 University
of California at Davis, 5 Liverpool JMU, 6 University of Portsmouth, 7 University of Hawaii, 8 Universidade do
Porto, Portugal, 9 University of Oxford, 10 Carnegie Mellon University)
We present a progress report on the serendipitous X-ray galaxy Cluster Survey (XCS) con-
ducted using archival data taken by XMM-Newton. Galaxy clusters trace the large-scale
distribution and their density evolution with cosmic time provides estimates of the cosmo-
logical parameters and constraints on hierarchical models of structure formation. The XCS
is designed to survey 500 square degrees of sky detecting clusters out to z∼2 allowing the
measurement of cosmological parameters to 5% accuracy. To date the XCS has covered a
search area of 200 square degrees and we have discovered 1500 extended sources, 300 of
which have more than 250 X-ray counts. These candidates are currently being followed up
from the ground as part of our approved NOAO survey programme of multi-band imaging
providing phot-z’s and hence X-ray luminosities and temperatures. Recent spectroscopy
from Keck has confirmed an XCS candidate as a z = 1.45 cluster, making it the most distant
X-ray selected cluster found to date and doubling the known sample size of these systems
at z>1.3.

A.4 Highlights from The XMM-Newton Slew Survey First Catalogue
Dr Andy Read (University of Leicester) - Oral presentation
A.M. Read 1 , R.D. Saxton 2 , M.P. Esquej 3 , M.J. Freyberg 3 , B. Altieri 2 (1 Leicester University, UK, 2 ESAC,
Spain,3 MPE, Germany)
XMM-Newton slew exposures yield at most only around 15 seconds of on-source exposure
time. With the high quantum efficiency of its EPIC detectors however, and the huge collect-
ing area of its mirrors, these exposures do actually constitute a hard-band 2-10 keV survey
some ten times deeper than all other all-sky surveys, and a soft-band 0.2-2 keV survey com-
parable with the ROSAT PSPC all-sky survey. With the release of the first source catalogue
(XMMSL1), we are able here to show a number of selected highlights seen so far; To date,
detailed source-searching has been performed in the EPIC-pn 0.2-12 keV band over ∼6,300
sq.degrees (∼15% of the sky), and of order 4000 X-ray sources have been detected (∼55% of
which have IDs). A great variety of sources are seen, including AGN, galaxies, clusters and
groups, active stars, SNRs, low- and high-mass XRBs and white dwarfs. In particular, the
great sensitivity and low-background of the EPIC-pn camera are especially suited to emis-
sion from extended sources, and interesting spatial structure is observed in many supernova
remnants and clusters of galaxies. Furthermore, as the slew survey is well matched to the
ROSAT all-sky survey, long-term variability studies are possible, and a number of extremely
variable X-ray sources have been discovered.

A.5 A joint XMM/SCUBA survey of high redshift radio galaxies: an ob-
    servational test of black hole / galaxy co-evolution models
Dr Olivia Johnson (University of Edinburgh) - Oral presentation
O. Almaini, University of Nottingham
We present a XMM-Newton study of high-redshift radio galaxies. Our sample has been
observed in the submillimetre and exhibits a wide range of implied star formation rates. We
use deep X-ray observations to determine the accretion rate and obscuration of the central
black holes in this sample. We use these measurements to test directly models of black hole
/ massive galaxy co-evolution in which a submillimetre-bright phase of heavily obscured
black hole growth is followed by rapid termination of star-formation as the quasar emerges.
Our X-ray observations also reveal at least one z = 2.5 radio galaxy surrounded by extended
soft X-ray emission, which we interpret as Inverse-Compton scattering of CMB photons.

A.6 Lobster - a new model for large scale X-ray surveys
Prof George Fraser (University of Leicester) - Oral presentation
N.P. Bannister1 , G.C. Stewart1 , S.A. Vaughan1 & P.T. O’Brien1 (1 University of Leicester, Department of Physics
& Astronomy).
The Lobster All-Sky X-ray Monitor successfully completed a detailed ESA Phase-A study
in 2005. The instrument is designed to image the entire X-ray sky in the 0.1 - 4.0 keV band,
every 90 minutes for the duration of its mission (several years). The scientific impact of
Lobster spans all of astronomy - from studies of the X-ray emission of comets to stars and
quasars, from regular X-ray binaries to the catastrophic events of supernovae and the enig-
matic gamma-ray bursts. Through frequent re-observation of each point in the sky during
the lifetime of the mission, Lobster-ISS offers the opportunity to perform deep, sensitive
surveys of both galactic and extra-galactic source populations, leading to the collation of a
“Lobster All-Sky Catalogue” containing hundreds of thousands of sources, including a sig-
nificant population of objects for which photometry on ∼1 day timescales will be available.
Such a rich catalogue of sources offers an unprecedented opportunity to study the large-scale
distribution of matter in the Universe, probing possible links between supercluster filamen-
tary structures and the purported existence of dark matter in the cosmos.

A.7 XMM-Newton Galactice Centre Survey
Dr Masaaki Sakano (Univ. Leicester) - Poster presentation
R. S. Warwick 1 , A. Decourchelle 2 , P. Predehl 3 , the GC Survey Team (1 Univ. Leicester, 2 CEA/Saclay, 3 MPE)
We present the results of the Galactic Centre Survey with XMM-Newton. We have surveyed
the central region of our Galaxy for 2 degree, mostly along the Galactic Plane, as well as
have made deep and recursive pointings in the central field with the cumulative exposure of
about 0.5 Ms. The Galactic Centre Region harbours many interesting objects and unresolved
phenomena, such as the central massive black hole (Sgr A∗ ), strong magnetic filaments (eg.,
the Radio Arc) and diffuse fluorescent line clouds (eg., Sgr B2). We have made a number of
discoveries and findings with XMM-Newton in this survey, such as recurrent X-ray flares
from Sgr A∗ , unusual transient X-ray sources and mixture of plasma and fluorescent X-ray
lines and its distribution. In this talk we summarise the highlights of our results and current
status in the survey.

A.8 XMM-2dF Wide Angle Serendipitous Survey
Dr Jonathan Tedds (University of Leicester) - Poster presentation
M.J. Page 2 , S. Mateos1 , M.G. Watson 1 , XMM-Newton Survey Science Centre 1 (1 University of Leicester,       2
The XMM-Newton Survey Science Centre (SSC) is carrying out an identification and follow-
up programme of serendipitous sources discovered in XMM-Newton observations. The
goals of this survey include the detailed characterisation of the dominant X-ray source pop-
ulations (e.g. AGN absorption distribution and evolution, the relationship between optical
emission line and X-ray spectral properties) and the discovery of new, rare classes of sources.
In addition to our ongoing core XID spectroscopic identification programme, we have now
targetted over 3000 sources, spread over 3 decades in X-ray flux, with 2dF in 27 pointings
including the LSS survey fields. We have reprocessed and finalised an X-ray catalogue for
all sources and have definite spectroscopic optical identifications for over 1000 sources with
F0.5−4.5keV > 10−14 erg/s/cm2 . This is an unsurpassed resource with which to investigate the
AGN population around the break in the X-ray source counts.

A.9 A deep look towards 3c273 with XMM-Newton
Mr Mark Simpson (University of Leicester) - Poster presentation
R. Smith 1 , P.T. O’Brien 1 , G.C. Stewart 1 , M. Stuhlinger     2
                                                                     (1 University of Leicester,   2
                                                                                                       European Space
The well known quasar 3c273 is a calibration target for the EPIC cameras on board XMM-
Newton and has been observed 19 times since the launch of the mission. 3c273 has itself
been studied in great depth, however the combination of the high throughput and large field
of view of XMM-Newton means that a number serendipitous sources can also be detected
in the observations. These frequent observations have resulted in a deep look (∼300ks) into
the field around 3c273 revealing more sources than a standard observation alone. A total
of 116 soures have been identified with a detection maximum likelihood greater than 12.
This poster looks at the x-ray properties of the targets, and their cross-correlation with other

A.10 XCS: XMM Cluster Survey
Mr Matthew Hilton (Liverpool JMU) - Poster presentation
Matt Hilton 1 , Chris Collins 1 , Michael Davidson 2 , Mark Hosmer 3 , Scott Kay 4 , Andrew Liddle 3 , Nicola
Mehrtens 3 , Bob Mann 2 , Chris Miller 5 , Bob Nichol 6 , Kathy Romer 3 , Kivanc Sabirli 7 , Adam Stanford 8 , Pedro
Viana 9 , Mike West 10 (1 ARI, Liverpool JMU, 2 IfA, Edinburgh, 3 University of Sussex, 4 Oxford University, 5
NOAO/CTIO, 6 University of Portsmouth, 7 Carnegie Mellon University, 8 University of California, Davis, 9
University of Hawaii, Hilo)
The XMM Cluster Survey (XCS; Romer et al. 2001) is an ambitious project aiming to search
∼500 square degrees of sky for serendipitous galaxy clusters in archival XMM-Newton ob-
servations. The goals of the project are to constraint cosmological parameters, study the
evolution of cluster scaling relations to high-redshift, and discover the most distant galaxy
clusters, in order to test models of cluster galaxy formation and evolution. In this poster
we give an update on recent progress, including an introduction to the NOAO-XCS (NXS)
optical follow-up survey, and report the discovery of the most distant, spectroscopically
confirmed X-ray cluster known to date at z = 1.45.
A.11 Normal Galaxies in the XMM-2DF Survey
Miss Yueheng XU (University of Leicester) - Poster presentation
Y. Xu 1 , M. Watson 1 , J. Tedds 1 , S. Mateos 1 , M. Page 2 , XMM-Newton Survey Science Centre (SSC) (1 XROA,
University of Leicester, 2 MSSL, University College London)
The XMM-2DF project aims to optically identify a significant sample of X-ray sources drawn
from XMM-Newton observations covering over 10 sq.degrees. using the AAT Two De-
gree Field system (2DF) on the Anglo-Australian Telescope (AAT). The 2DF observations
carried out provide optical spectra for around 3000 potential counterparts to XMM X-ray
sources down to ∼ 21 R band magnitude. Of these ∼1000 X-ray sources have been positively
identified.<p>In this paper we discuss a sample of 57 galaxies which are the 2DF X-ray
counterparts, which show normal or narrow emission line spectra and which satisfy the
criteria: (1) X-ray flux to optical flux ratios ≤ 0.1, and (2) X-ray luminosities ≤ 10 43 erg/s.
This sample is expected to include a variety of non-active (ie "normal") and low luminosity
AGN. We discuss the classification of these galaxies in terms of the underlying emission
mechanisms using the X-ray colours and morphology from XMM and optical spectra from
2DF, combined with the optical morphology. For around 10 galaxies in the sample for which
the XMM observations provide sufficient photon counts, we also present a detailed X-ray
spectral analysis which allows further refinement of the correct classification.

A.12 The 2XMM Survey
Dr Clive Page (University of Leicester) - Poster presentation
G.Denkinson, D.Fyfe, J.Osborne, J.Pye, A.Schroeder, J.Tedds, S.Mateos, M.Sakano, M.Watson (University of
The 1XMM serendipitous source catalogue was released in 2003 and contained some 50,000
sources. Since then much work has been done by the SSC and SOC to extend and improve
the functionality of the SAS and make this available through the SSC Pipeline processing
system. The upcoming 2XMM catalogue is geared to take advantage of all of these advances
with a reprocessing of some 4000 public XMM data sets.
    This will provide an X-Ray source catalogue with at least 150,000 unique sources. The
catalogue will have improved reliability and source parameterization compared to 1XMM.
It will also provide automatically generated source spectra and time-series for the brightest
10% of sources.

A.13 The XMM-Newton Slew Survey and The First Catalogue (XMMSL1)
Miss M. Pili Esquej (MPE) - Poster presentation
A.M. Read 1 , R.D. Saxton 2 , M.J. Freyberg 3 , B. Altieri 2 (1 Leicester University, UK, 2 ESAC, Spain,3 MPE,
XMM-Newton, with the huge collecting area of its mirrors and the high quantum efficiency
of its EPIC detectors, is the most sensitive X-ray observatory ever flown. This is strikingly
evident during slew exposures, which, while yielding only at most around 15 seconds of
on-source exposure time, actually constitute a hard-band 2-10 keV survey ten times deeper
than all other all-sky surveys, and a soft-band 0.2-2 keV survey comparable with the ROSAT
PSPC all-sky survey, offering long-term variability studies. The current XMM slew archive
contains 374 slew exposures which give a uniform coverage over around 10,000 sq.degrees
(∼25% of the sky). Here we outline the reduction and analysis of the slew data, and describe
the current status of the XMM-Newton Slew Survey and the first source catalogue: We have
performed detailed source-searching over ∼6,300 sq.degrees in the EPIC-pn 0.2-12 keV band,
and have detected of order 4000 X-ray sources (∼55% of which have IDs). A great variety of
sources have been detected, and we reveal here many of the highlights so far. In particular,
the low background and great sensitivity of the EPIC-pn camera are especially suited to the
detection of extended sources, and many clusters of galaxies and supernova remnants have
been detected. We aim to release the first XMM-Newton slew catalogue by March 2006.
Later observations and detections will be continuously added, as the mission progresses and
the sky coverage and depth increases.

A.14 Photometric Redshifts and Serendipitous Large X-ray Surveys
Miss Rebecca Smith (University of Leicester) - Poster presentation
G.C. Stewart (University of Leicester).
The release of large X-ray catalogues such as 1XMM enable the astrophysical properties of
large samples of X-ray emitting sources to be investigated. Many such analyses, however,
e.g. QSO luminosity function evolution, require redshifts for objects in the sample. Spectro-
scopically determined redshifts, although accurate, are telescope-time consuming to collect,
even with multi-object spectrographs. Photometric redshift estimates, which are much more
efficient, might be sufficient for a number of these astrophysical studies.
    Here we quantify the reliability and accuracy of photometric redshifts using a set of X-ray
sources which have been extensively followed up spectroscopically and for which there is
high quality multi-band photometry available (Sloan Digital Sky Survey (SDSS) and J band
data). Using a photometric redshift code (Weinstein et al, ApJS, 155, 243, 2004) specifically for
use with SDSS colours we find that, by selecting an appropriate trainer catalogue of known
redshift objects, we can obtain a photometric redshift in agreement with the one obtained
spectroscopically for over 80% of the point sources for which a reliable photometric ID can
be made. The rms scatter of ∆z/z for these objects is ∼ 14%.

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