Gamma-ray Burst 080828

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #8151
  E. Del Monte, P. Soffitta, I. Donnarumma, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and P. Giommi, C. Pittori, B. Preger, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, report:
  "SuperAGILE detected a gamma ray burst on 28 August 2008, at 03:14:45 UT. The event had a duration of about 25 s in the 20-60 keV energy range, with a single-peak structure. The burst position was reconstructed as (RA, Dec) (199.626 deg, -65.930 deg), which is:

  RA(J2000)  = 13h 18m 30.32s
  Dec(J2000) = -65d 55' 48.2"
  

  with an uncertainty of 3' radius. The given uncertainty accounts for both the statistical and systematic errors.
  An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."
  This message may be cited.
• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SuperAGILE NOTICE
  NOTICE_DATE:     Thu 28 Aug 08 07:22:50 UT
  NOTICE_TYPE:     SuperAGILE GRB Ground Position
  TRIGGER_NUM:     600
  GRB_RA:          199.626d {+13h 18m 30s} (J2000),
                   199.773d {+13h 19m 06s} (current),
                   198.782d {+13h 15m 08s} (1950)
  GRB_DEC:         -65.930d {-65d 55' 47"} (J2000),
                   -65.975d {-65d 58' 30"} (current),
                   -65.667d {-65d 40' 00"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical plus systematic]
  GRB_INTEN:       199.666   204.820 [X & Y cnts]
  GRB_SIGNIF:      5.23  5.54 [sigma]
  GRB_DATE:        14706 TJD;   241 DOY;   08/08/28
  GRB_TIME:        11685.01 SOD {03:14:45.01} UT
  SUN_POSTN:       157.18d {+10h 28m 42s}   +9.55d {+09d 32' 42"}
  SUN_DIST:         81.72 [deg]   Sun_angle= -2.8 [hr] (East of Sun)
  MOON_POSTN:      125.20d {+08h 20m 47s}  +20.91d {+20d 54' 31"}
  MOON_DIST:       102.99 [deg]
  MOON_ILLUM:      8 [%]
  GAL_COORDS:      305.69, -3.20 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      231.84,-51.56 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SuperAGILE GRB Coordinates.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        SuperAGILE ground GRB coordinates  
  

• red DSS finding chart ps-file
  
  
• GCN Circular #8157
  A.P. Beardmore and R.L.C. Starling (U. Leicester) report on behalf of the Swift-XRT team:
  The Swift-XRT began observations of the field of the SuperAGILE detected GRB 080828 (Del Monte et al., GCN Circ 8151) at 2008-08-28 14:07:17UT, 39.15 ks after the burst. In 4.96 ks of photon counting mode data we detect a faint, uncatalogued X-ray source at RA, Dec 199.5871, -65.9405 which is

  RA  (J2000) =  13:18:20.91
  Dec (J2000) = -65:56:25.8
  

  with an uncertainty of 4.2 arcsec (radius, 90% containment). This source is 1.1 arcmin away from the AGILE position and within its error circle.
  The measured XRT count rate is 0.008 +/- 0.001 count/s. At this stage we cannot tell whether the source is fading.
  This circular is an official product of the Swift-XRT team.
• GCN Circular #8161
  P. Ward (MSSL-UCL) and W. Baumgartner (GSFC/UMBC) report on behalf of the Swift/UVOT team:
  The Swift/UVOT observed the field of GRB 080828 starting 39.15ks after the SuperAGILE detection (Del Monte et al., GCN Circ. 8151). We do not detect any afterglow at the Swift XRT position reported by Beardmore et al. (GCN Circ. 8157) in any of the following UVOT filters down to the given 3 sigma upper limits.

  Filter T_start(s) T_stop Exp(s)  MagLimit
  
  White  46201      46561  355.8   > 21.40
  u      44376      51948  1798.8  > 20.65
  b      45289      52309  1250.3  > 21.33
  w1     40064      51035  1615.6  > 21.05
  m2     39156      40055  899.8   > 20.50
  

  The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383,627). The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E(B-V) ~ 0.81 mag (Schlegel et al., 1998).