gehrels by dandanhuanghuang

VIEWS: 18 PAGES: 27

									     UVOT                               BAT




                               Cnts/s
Global Approach to Swift GRB Science
  XRT               Neil Gehrels
                   NASA-GSFC


                  San Servolo, Venice
                     June 5, 2006
Swift recently reviewed at NASA, ASI, PPARC

Success at NASA & ASI. Pending at PPARC.

NASA review involved 20-page detailed proposal
and formal presentation to peer review committee
          Contributors to NASA Proposal



Writers:
Angelini, Berger, Brown, Boyd, Burrows, Chincarini, Cominsky,
Cusumano, Della Valle, Dingus, Fox, Fruchter, Gehrels, Giommi,
Goad, Grupe, Hurley, Immler, Krimm, Kulkarni, Lamb, Markwardt,
Marshall, Meszaros, Mushotzky, Nousek, O'Brien, Osborne, Salotti,
Tueller, Wells, Woosley, Zhang

Presenters:
Gehrels, Nousek

Reviewers:
Burrows, Chincarini, Giommi, Grupe, Feigelson, Fox, Mason,
Meszaros, Osborne, Ritz, Roming, Schneider, Taylor, Wells, White,
Swift Science Team
                           Outline

                                     Nov. 20, 2004

High Redshift Universe

Short GRBs

Supernovae & GRB Connection

Afterglows & Jet Physics

Recent GRBs (last night, 060526)
                       High Redshift Universe



   GRBs hold huge promise for early universe studies

   GRBs & afterglows are brightest high-z objects
       (opt: 17th mag, x-ray: 10-9 erg cm-2 s-1)
   Afterglow studies provide:                          Redshift Records (Mcmahon & Tanvir)
     -  Metallicities / abundances
     -  Densities
        Dust ratios




                                                        Redshift
     -


   Over next 4 years will observe GRBs to z>7
    Unique probes of earliest stars & reionization



                                                                      Year
 GRB 050730

Redshift z= 3.97 (12.1 Gyr)
T90 = 155 sec
S (15-350 keV) = 4.4x10-6 erg cm-2




        UVOT                         Time dilation
        V=17 !!                       - increases duration
                                      - smooths lightcurve
  GRB 050904

Redshift z= 6.29 (12.8 Gyr)
T90 = 225 sec
S (15-150 keV) = 5.4x10-6 erg cm-2
Eiso = 3.8x1053 erg




                                        Very bright in IR
                                       J= 17.5 @ 3 hours
                                            (SOAR)


                                     Flux x100 of high-z
                                     luminous X-ray AGN
GRB 050904 Optical Spectroscopy


Ly break in the IR
                                             z= 0 z ~ 1   z = 2.3


   Subaru Spectroscopy




                         log (metallicity)
                                               z = 6.3



                                                  Mgalaxy (mag)

                                                 Berger et al. 2006
                                               Subaru, HST & SIRTF
Kawai et al. 2006
Higher Recent Rate of High-z GRBs




             Swift GRBs with z>4




             2005         2006
                     Promise for the Future
    z


Studies of Swift detection rates at high-z
 - Lamb and Reichart 2000                                              SFR
                                                                     SFR
 - Ciardi and Loeb 2002
 - Bromm & Loeb 2006

Assumption: long GRBs track SFR

Prediction:
 - 7% - 10% of Swift GRBs at z>5                                z
  (Bromm & Loeb 10%, Jakobbson et al. 7%)
                                                               Swift GRB
                                                           d NGRB / d ln(1+z)
 - ~0.5% at z>10                                                     Rate
                                            .
With 4 more years, large sample of high-z
GRB for unique studies of
 - metallicity
 - environments
 - reionization                                                  z
 - cosmology                                    Bromm & Loeb 2006
                           Short GRBs


   2005 was breakthrough year for short GRBs

   Major progress on:
     -   Distance scale
     -   Progenitor type
     -   Beaming
     -   Environments
     -   Energetics
   However, understanding is still highly incomplete
     - Diverse and complex sample of events
     - Few well-measured bursts
     - Afterglows often weak

   Over next 4 years will detect 40 more short GRBs,
    20 with afterglow and accurate positions
                Variability - BATSE


Counting Rate




                                 0   0.4     0.6
                     (s)
                 TimeTime (1 second ticks)
Variability -   Swift
             Long GRBs          Short GRBs
                         XRT             050509B
                                                      cD elliptical
                                                    SFR < 0.2 MO yr-1
                                              BAT      z = 0.225


                                         050709

    SF                                                 SF galaxy
irregulars                                             with offset
                                                       z = 0.161
                               HETE-2 / HST


                               XRT        050724
                                                        elliptical
                                                    SFR < 0.02 MO yr-1
                                          Chandra       z = 0.258
      Soft Hard X-ray Bump

                              XRT             050509B

        GRB 050709

                                                   BAT




                                              050709
0      100       200    300

    Time (sec)


      GRB 050724                    HETE-2 / HST


                                    XRT       050724
     Time (sec)


0       100       200                          Chandra

    Time (sec)
Name         Redshift      Afteglow      Host         Eiso      Duration$   Temporal        Origin?
                                                   (1050 erg)
                                                       (s)                  Lag (ms)
____________________________________________________________________________________

050509B      0.225         X          elliptical@      0.01      0.042      4.3±3.2     NS-NS%
050709*      0.161         X, O       SF galaxy        0.6       0.07       0.0±2.0     NS-NS%
050724       0.258         X, O, R    elliptical       3         0.276      -4.2±8.2    NS-NS%
050813       0.7 (?) 1.8   X          galaxy@          -         0.012      -9.7±14.0   -
050906       -             -          ? galaxy         -         0.162      -           -
050925#      -             -          in gal. plane    -         0.056      -           ? new SGR
051105A      -             -          -                -         0.098      6.3±5.3
051210       -             X          ? cluster@       -         0.852      -5.3±24.0   -
051221A      0.547         X, O, R    SF galaxy        0.2       1.35       0.8±0.5     -
060121*      1.5 (?) 4.5   X, O       galaxy           -         1.97       2±29        -
060313       -             X, O       ? cluster@       -         0.736      0.3±0.7     -
060502B      -             X          ? galaxy         -         0.048      -0.2±2.8    -


$ T90 in 30-350 (400) keV
* HETE GRB
# soft spectrum
@ galaxy in cluster
% not related to massive stars, consistent with NS-NS merger models
          GRBs Without XRT Detection


Name      BAT Fluence    GRB Type     Time to    Comments
           (erg cm-2 )               Observation
060102        2.4        long GRB      2 days     No prompt slew (moon constraint)

051114        1.32       long GRB     1.5 days    Did not trigger BAT (found in ground
                                                  processing)
051105A       0.2        short GRB     68 sec

050925        0.75       short GRB     100 sec

050911        3.01       long XRR     3.6 hours   No prompt slew (Earth limb
                                                  constraint)
050906       0.0721      short GRB      79 s

050528        4.40       long XRR     14 hours    XRT in engineering mode at trigger
                                                  time
050416B       11.3       long GRB     3.6 days    No prompt slew (tmoon constraint)
                    Promise for the Future
    z


Since tuning short triggers in early 2005, Swift is
detecting ~10 short GRBs per year.

With 4 more years, expect:
- 40 additional short GRBs
- ~20 with afterglow detection & counterparts

Questions to answer:
 * What are progenitors? DNS, AIC, ...
 * Do old populations in globular clusters
contribute?
 * How many short GRBs are extragalactic SGRs?
 * Is there a high-redshift sub-class?
 * Standard candles for cosmology studies?
 * What do afterglows teach about jet physics?
 * How much collimation is there?
 * What is NS-NS merger rate for GW detection?
                Supernovae and GRB Connection


    Recent GRB 060218 galvanized the community
         Oddball z=0.03 GRB triggered supernova discovery
             Shock break-out seen for first time
         GRBs are new tool for SN understanding (hypernovae, BH cores, asymmetries, jets)
         Next 4 years will provide ~4 more GRBs associated with rare "hypernova" SN Ic's

    Swift is providing important data on SNe
         20 observed to date of all types    SDSS                  060218 - UVOT
         UV, optical & X-ray densely-sampled light curves
         Unique UV characterizations of SN Ia's
         Swift SN team expanded to full community
         Next 4 years will provide largest available data set

                         XRT        UVOT opt         UVOT UV

SN 2006bp
 (SN II)
                        GRB 060218


                      BAT




                                                      Mirabal et al.

                      XRT
                            Super-long GRB - ~35 minutes
                            BAT, XRT, UVOT during GRB
                            VLA detection at 0.5 mJy
                            z = 0.033
                            Eiso = few x 1049 erg cm-2
                            SN 2006aj - SN Ic
Campana et al. 2006
              UVOT Supernova Observations
         Lightcurve
                           Image near peak, March 3, 2005




                                                            NCG 2811
            Spectra                                          34 Mpc




                      SN 2005am (Ia)   SN 2005az (Ib)     SN 2006E (Ia)
                      SN 2005cf (Ia)   SN 2005cs (II)     SN 2006X (Ia)
                      SN 2005da (Ic)   SN 2005df (Ia)     SN 2006at (IIp)
                      SN 2005ek (Ic)   SN 2005ke (Ia)     SN 2006bc (II)
                      SN 2005gj (Ia)   SN 2005bf (Ib/c)   SN 2006bp (II)
Brown et al. 2005     SN 2006E (Ia)
    UVOT Observations of SN Ia




                UVOT UVW1
            lightcurves of SN Ia's



                                                  Immler et al. 2006
Are Type Ia SNe standard candles in UV?

If so, could greatly enhance cosmology studies.
Afterglow Observations & Jet Physics


                   Canonical
                                                             Afterglow
                   Lightcurve
                                                               Flare
                     Shape



GRB 051001 - XRT
                                                 GRB 050502B - XRT




       Curves &             New multi-component afterglow paradigm
       Breaks
                            Basic questions remain open:
                            * Is outflow particle or poynting driven?
GRB 050525A                 * What causes flares and rebrightenings?
UVOT
                            * What are jet configurations (long, short GRBs)?
                            * What are manifestations of off-axis viewings?
                   Theme for GRB Science




Rare events lead to the biggest steps forward:
       GRB 050904 -- at z=6.29, awakened community to high-z GRB potential
       A few short GRBs have led to a breakthrough in understanding
       GRB 060218 -- at z=0.03, trigger for unique GRB-SN observation
       SGR 1806-20 -- largest magnetar flare in 30 years




ν   ⇒ GRB science discovery grows linearly with time
          Other Opportunities in Next 4 Years

   Expanded Swift non-GRB science in areas of:
     Hard X-ray survey (most sensitive of any mission)         Swift Hard X-ray Sky Survey
     Transients (rapid-response multi-λ campaigns)                   . ... . . ... .... . .... .. . .
                                                                .... . . . ...... . . . . . . . . .
     CV's (rapid response, spectroscopy)                       ... . . . . . . . . ..
                                                            . ... .... .. . . .. . . . .. .. .
                                                         . ..                                           .
     AGN (multiwavelength monitoring)                    . . . ... .. . .................... . . .. .. . ..... .
                                                              .. .. .......... . ... ..... .. .. . . ... .. .
                                                                        ..
                                                         . . . . . ..... ...... ..... .... ..... ....
                                                          ..  ..... . .. ..... .. . . . . . . . .
   Enhanced GI program:                                                  ... .. . ... .. ...... . .. . .
                                                               . . . . . . .. .. ..                  ..
     Target of Opportunities in cycle 3                                        .. .
     Pointed observations in cycle 4 (FY08)


   Critical enabling support for other observatories:                    Largest GRB dataset.
     GLAST & AGILE                                                        All available to public
     TeV observatories (HESS, VERITAS, Milagro, ...)
     SPITZER
     SUZAKU, INTEGRAL, HETE-2
     AMANDA & ICECUBE
     LIGO
GRB 060526




  Alberto Moretti
                            Last Night's Burst




T90 = 10 s

S = 1.3x10-7 erg cm-2 s-1

								
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