Gamma-ray Burst 090628

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 21:20:31 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     355942,   Seg_Num: 0
  GRB_RA:            0.000d {+00h 00m 00s} (J2000),
                     0.122d {+00h 00m 29s} (current),
                    -0.641d {-00h 02m 33s} (1950)
  GRB_DEC:         -214748.365d {-214748d 21' 52"} (J2000),
                   -214748.312d {-214748d 18' 42"} (current),
                   -214748.643d {-214748d 38' 35"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       0 [cnts]    Image_Peak=0 [image_cnts]
  TRIGGER_DUR:     196.436 [sec]   (=3.3 [min])
  TRIGGER_INDEX:   146     E_range: 15-25 keV
  BKG_INTEN:       -1810691852 [cnts]
  BKG_TIME:        58659.13 SOD {16:17:39.13} UT
  BKG_DUR:         48922 [sec]
  GRB_DATE:        15010 TJD;   179 DOY;   09/06/28
  GRB_TIME:        76812.02 SOD {21:20:12.02} UT
  GRB_PHI:           0.00 [deg]
  GRB_THETA:       -21474836.00 [deg]
  SOLN_STATUS:     0xAF40
  RATE_SIGNIF:     5.47 [sigma]
  IMAGE_SIGNIF:    17380.00 [sigma]
  MERIT_PARAMS:     +0  +0  +0  +0  +0  +0  +0 -56 +67 -28 
  SUN_POSTN:        97.94d {+06h 31m 46s}  +23.24d {+23d 14' 13"}
  SUN_DIST:         79.59 [deg]   Sun_angle= 6.5 [hr] (West of Sun)
  MOON_POSTN:      178.29d {+11h 53m 09s}   -4.15d {-04d 08' 58"}
  MOON_DIST:        12.60 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:       87.58, 67.63 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      356.65,  7.67 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        WARNING: This Notice was received with 1 (or more) critical values out of range.  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was not found.  
  COMMENTS:        This matches a source that was purposefully removed from the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        There is a bright star (mag=0.00) 0.00 arcmin from this position.  
  COMMENTS:        This is not a GRB.  
  COMMENTS:        This trigger occurred during a high background rate interval.  
  COMMENTS:           
  COMMENTS:        The IMAGE_SIGNIF is VERY LOW, this is very likely not real.  
  COMMENTS:        Since the foreground interval count rate is less than the bkg interval (SAA exit), this is a questionable detection.  
  COMMENTS:        This trigger occurred at longitude,latitude = 112.49,-15.94 [deg].  
  COMMENTS:           
  COMMENTS:        This trigger occured while the StarTracker had lost lock, so it is possibly bogus.  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 21:23:43 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     355942,   Seg_Num: 0
  GRB_RA:          237.050d {+15h 48m 12s} (J2000),
                   237.184d {+15h 48m 44s} (current),
                   236.343d {+15h 45m 22s} (1950)
  GRB_DEC:         -15.977d {-15d 58' 36"} (J2000),
                   -16.006d {-16d 00' 19"} (current),
                   -15.824d {-15d 49' 26"} (1950)
  GRB_DATE:        15010 TJD;   179 DOY;   09/06/28
  GRB_TIME:        76812.02 SOD {21:20:12.02} UT
  TRIGGER_INDEX:   146
  GRB_PHI:         -40.43 [deg]
  GRB_THETA:        31.27 [deg]
  DELTA_TIME:      71.00 [sec]
  TRIGGER_DUR:     196.436 [sec]   (=3.3 [min])
  SOLN_STATUS:     0xAF40
  RATE_SIGNIF:     0.00 [sigma]
  IMAGE_SIGNIF:    0.00 [sigma]
  LC_URL:          sw00355942000msb.lc
  SUN_POSTN:        97.94d {+06h 31m 46s}  +23.24d {+23d 14' 12"}
  SUN_DIST:        141.06 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      178.31d {+11h 53m 15s}   -4.16d {-04d 09' 46"}
  MOON_DIST:        58.96 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:      353.08, 29.21 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      238.39,  3.92 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Lightcurve.  
  COMMENTS:        This Notice is generated as a result of an uploaded TOO -- this is not a normal BAT-detected burst.  
  COMMENTS:           
  COMMENTS:        The next comments were copied from the BAT_POS Notice:  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was not found.  
  COMMENTS:        This matches a source that was purposefully removed from the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        There is a bright star (mag=0.00) 0.00 arcmin from this position.  
  COMMENTS:        This is not a GRB.  
  COMMENTS:        This trigger occurred during a high background rate interval.  
  COMMENTS:           
  COMMENTS:        The IMAGE_SIGNIF is VERY LOW, this is very likely not real.  
  COMMENTS:        Since the foreground interval count rate is less than the bkg interval (SAA exit), this is a questionable detection.  
  COMMENTS:        This trigger occurred at longitude,latitude = 112.49,-15.94 [deg].  
  COMMENTS:           
  COMMENTS:        This trigger occured while the StarTracker had lost lock, so it is possibly bogus.
  

  
• GCN NOTICE
  

  TITLE:        GCN/SIMBAD_NED NOTICE
  NOTICE_DATE:  Sun Jun 28 21:56:02 UTC 2009
  NOTICE_TYPE:  Swift-BAT Position search
  TRIGGER_NUM:  355942
  RA:           237.0500 (J2000)
  DEC:          -15.9770 (J2000)
   
  SIMBAD search for BAT_RA,Dec=237.0500,-15.9770,radius=10.0arcmin
   
  Num   RA         Dec                    Name                        Type  Num_Pub  Distance
  

• GCN Circular #9585
  V. Mangano (INAF-IASFPA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), E. A. Hoversten (PSU), J. A. Kennea (PSU), D. M. Palmer (LANL), B. Sbarufatti (INAF-IASFPA), M. Stamatikos (NASA/ORAU) and M. A. Stark (PSU) report on behalf of the Swift Team:
  At 21:20:12 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090628 (trigger=355942). Swift could not immediately slew to the burst. The BAT on-board calculated location is RA, Dec 237.050, -15.977 which is

     RA(J2000)  =  15h 48m 12s
     Dec(J2000) = -15d 58' 36"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak structure with a duration of about 5 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger.
  Due to an Earth limb constraint, a prompt slew was not possible. Swift will execute a delayed slew after 2656 s. No XRT or UVOT data will be available until the slew occurs.
  The series GCN Notices for this burst are corrupted with many (but not all) bogus values. For the moment, please disregard the original series of notices. We may issue Updated position notices when the information becomes available.
  Burst Advocate for this burst is V. Mangano (vanessa AT ifc.inaf.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 21:57:24 UT
  NOTICE_TYPE:     Swift-BAT GRB Position UPDATE
  TRIGGER_NUM:     355942,   Seg_Num: 0
  GRB_RA:          237.050d {+15h 48m 12s} (J2000),
                   237.184d {+15h 48m 44s} (current),
                   236.343d {+15h 45m 22s} (1950)
  GRB_DEC:         -15.977d {-15d 58' 36"} (J2000),
                   -16.006d {-16d 00' 19"} (current),
                   -15.824d {-15d 49' 26"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       0 [cnts]    Image_Peak=0 [image_cnts]
  TRIGGER_DUR:     1.000 [sec] 
  TRIGGER_INDEX:   146     E_range: 15-25 keV
  BKG_INTEN:       0 [cnts]
  BKG_TIME:        0.00 SOD {00:00:00.00} UT
  BKG_DUR:         0 [sec]
  GRB_DATE:        15010 TJD;   179 DOY;   09/06/28
  GRB_TIME:        76812.02 SOD {21:20:12.02} UT
  GRB_PHI:         -40.43 [deg]
  GRB_THETA:        31.27 [deg]
  SOLN_STATUS:     0x3000AF40
  RATE_SIGNIF:     5.46 [sigma]
  IMAGE_SIGNIF:    7.00 [sigma]
  MERIT_PARAMS:     +0  +0  +0  +0  +0  +0  +0 -56 +67 -28 
  SUN_POSTN:        97.97d {+06h 31m 52s}  +23.24d {+23d 14' 08"}
  SUN_DIST:        141.04 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      178.60d {+11h 54m 23s}   -4.30d {-04d 18' 11"}
  MOON_DIST:        58.65 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:      353.08, 29.21 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      238.39,  3.92 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was not found.  
  COMMENTS:        This matches a source that was purposefully removed from the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        There is a bright star (mag=0.00) 0.00 arcmin from this position.  
  COMMENTS:        This is not a GRB.  
  COMMENTS:        This trigger occurred during a high background rate interval.  
  COMMENTS:           
  COMMENTS:        The IMAGE_SIGNIF is VERY LOW, this is very likely not real.  
  COMMENTS:        Since the foreground interval count rate is less than the bkg interval (SAA exit), this is a questionable detection.  
  COMMENTS:        This trigger occurred at longitude,latitude = 0.00,0.00 [deg].  
  COMMENTS:           
  COMMENTS:        This trigger occured while the StarTracker had lost lock, so it is possibly bogus.  
  COMMENTS:        This Notice was ground-reprocessed from flight-data.  
  COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous BAT_POS Notice.  
  COMMENTS:           
  COMMENTS:        NOTE: This BAT event is spatially(0.00<0.1deg) and temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=355942).  
  COMMENTS:          
  COMMENTS:        This is manually generated notice to replace the original bogus Position notice.  
  COMMENTS:        Many of the fileds are unknown and are filled with zeros.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 22:06:59 UT
  NOTICE_TYPE:     Swift-XRT Nack-Position
  TRIGGER_NUM:     355942,   Seg_Num: 0
  POINT_RA:        237.029d {+15h 48m 07s} (J2000)
  POINT_DEC:       -15.941d {-15d 56' 26"} (J2000)
  IMG_START_DATE:  15010 TJD;   179 DOY;   09/06/28
  IMG_START_TIME:  79598.64 SOD {22:06:38.64} UT,   2786.6 [sec] since BAT Trigger Time
  COUNTS:          1    Min_needed= 20
  STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
  PH2_ITER:        0    Max_iter_allowed= 4
  ERROR_CODE:      1
  COMMENTS:        SWIFT-XRT Nack Position.  
  COMMENTS:        No source found in the image.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 22:11:08 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     355942,   Seg_Num: 0
  POINT_RA:        237.029d {+15h 48m 07s} (J2000)
  POINT_DEC:       -15.941d {-15d 56' 25"} (J2000)
  POINT_ROLL:      287.375d
  IMG_START_DATE:  15010 TJD;   179 DOY;   09/06/28
  IMG_START_TIME:  79602.96 SOD {22:06:42.96} UT,   2790.9 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        6.115
  N_STARS:         83
  X_OFFSET:        170 [pixels]
  Y_OFFSET:        473 [pixels]
  X_MAX:           1129 [pixels]
  Y_MAX:           1432 [pixels]
  DET_THRESH:      21
  PHOTO_THRESH:    13
  SL_URL:          sw00355942000msufc2790.fits
  SUN_POSTN:        97.98d {+06h 31m 54s}  +23.23d {+23d 14' 06"}
  SUN_DIST:        141.00 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      178.71d {+11h 54m 51s}   -4.36d {-04d 21' 37"}
  MOON_DIST:        58.50 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:      353.10, 29.25 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      238.36,  3.95 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 22:11:08 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     355942,   Seg_Num: 0
  POINT_RA:        237.029d {+15h 48m 07s} (J2000)
  POINT_DEC:       -15.941d {-15d 56' 25"} (J2000)
  POINT_ROLL:      287.375d
  IMG_START_DATE:  15010 TJD;   179 DOY;   09/06/28
  IMG_START_TIME:  79602.96 SOD {22:06:42.96} UT,   2790.9 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        6.115
  N_STARS:         83
  X_OFFSET:        170 [pixels]
  Y_OFFSET:        473 [pixels]
  X_MAX:           1129 [pixels]
  Y_MAX:           1432 [pixels]
  DET_THRESH:      21
  PHOTO_THRESH:    13
  SL_URL:          sw00355942000msufc2790.fits
  SUN_POSTN:        97.98d {+06h 31m 54s}  +23.23d {+23d 14' 06"}
  SUN_DIST:        141.00 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      178.71d {+11h 54m 51s}   -4.36d {-04d 21' 37"}
  MOON_DIST:        58.50 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:      353.10, 29.25 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      238.36,  3.95 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 22:12:35 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     355942,   Seg_Num: 0
  POINT_RA:        237.029d {+15h 48m 07s} (J2000)
  POINT_DEC:       -15.941d {-15d 56' 25"} (J2000)
  ROLL:            287.375d
  IMG_START_DATE:  15010 TJD;   179 DOY;   09/06/28
  IMG_START_TIME:  79602.96 SOD {22:06:42.96} UT,   2790.9 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     267919607
  X_OFFSET:        489 [pixels]
  Y_OFFSET:        792 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       649
  Y_GRB_POS:       952
  BINNING_INDEX:   1
  IM_URL:          sw00355942000msuni2795.fits
  SUN_POSTN:        97.98d {+06h 31m 55s}  +23.23d {+23d 14' 06"}
  SUN_DIST:        141.00 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      178.73d {+11h 54m 54s}   -4.37d {-04d 21' 59"}
  MOON_DIST:        58.49 [deg]
  MOON_ILLUM:      44 [%]
  GAL_COORDS:      353.10, 29.25 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      238.36,  3.95 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Sun 28 Jun 09 23:04:24 UT
  NOTICE_TYPE:     Swift-XRT Position
  TRIGGER_NUM:     355942,   Seg_Num: 0
  GRB_RA:          237.0535d {+15h 48m 12.84s} (J2000),
                   237.1878d {+15h 48m 45.07s} (current),
                   236.3467d {+15h 45m 23.19s} (1950)
  GRB_DEC:         -15.9857d {-15d 59' 08.5"} (J2000),
                   -16.0144d {-16d 00' 51.7"} (current),
                   -15.8328d {-15d 49' 58.2"} (1950)
  GRB_ERROR:       6.5 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       2.39e-12 [erg/cm2/sec]
  GRB_SIGNIF:      4.09 [sigma]
  IMG_START_DATE:  15010 TJD;   179 DOY;   09/06/28
  IMG_START_TIME:  79598.63 SOD {22:06:38.63} UT,   2786.6 [sec] since BAT Trigger Time
  TAM[0-3]:        327.61 237.19 261.35 242.66
  AMPLIFIER:       2
  WAVEFORM:        134
  SUN_POSTN:        98.01d {+06h 32m 04s}  +23.23d {+23d 13' 59"}
  SUN_DIST:        141.00 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
  MOON_POSTN:      179.16d {+11h 56m 39s}   -4.58d {-04d 34' 54"}
  MOON_DIST:        58.04 [deg]
  MOON_ILLUM:      45 [%]
  GAL_COORDS:      353.08, 29.20 [deg] galactic lon,lat of the burst
  ECL_COORDS:      238.40,  3.91 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        TAM values are not valid.   
  

• GCN Circular #9586
  B. Sbarufatti, V. Mangano (INAF-IASF PA) report on behalf the Swift XRT team:
  Analysis of preliminary data from the BAT trigger 355942 (GRB090628, Mangano, et al., GCN Circ 9585) reveals an uncatalogued point source at RA, Dec = 237.05355, -15.98577 which is equivalent to:

  RA(J2000) = 15h48m12.85s
  Dec(J2000) = -15:59:08.79
  

  with an estimated uncertainty of 6.5 arcseconds radius (90% confidence). Analysis is ongoing and an improved analysis will be reported as soon as more data will be available.
  This is an official product of the Swift XRT team.
• GCN Circular #9587
  E. A. Hoversten and V. Mangano (INAF-IASFPA) report on behalf of the Swift UVOT team:
  UVOT took a finding chart exposure of 150 seconds with the White filter starting 2790 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.18.
• GCN Circular #9589
  P. Kubanek (IAA-CSIC & GACE), N. Morales (IAA-CSIC), J.L. Ortiz (IAA-CSIC), A. de Ugarte Postigo (ESO, INAF/OAB), J. Gorosabel (IAA-CSIC), A.J. Castro-Tirado (IAA-CSIC), M. Jelinek (IAA-CSIC), report on behalf of a larger collaboration:
  We carried out R-band observations of the GRB 090628 XRT position (Sbarufatti et al., GCN 9586) with the 1.23m Calar Alto telescope. The observations were done on June 28.9486-29.0225 UT (1.43-3.20 hours post GRB) with an exposure time of 3120s. A quick inspection of the XRT error box reveals no object brighter than R ~ 22.
• GCN Circular #9590
  M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
  Using 3973 s of XRT Photon Counting mode data and 2 UVOT images for GRB 090628, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 237.05272, -15.98489 which is equivalent to:

  RA (J2000): 15h 48m 12.65s
  Dec (J2000): -15d 59' 05.6"
  

  with an uncertainty of 1.9 arcsec (radius, 90% confidence).
  This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, arXiv:0812.3662).
  This circular was automatically generated, and is an official product of the Swift-XRT team.
• GCN Circular #9591
  T. Kruehler (MPE Garching), S. Klose (Tautenburg) and J. Greiner (MPE Garching) report on behalf of the GROND team:
  We observed the field of GRB 090628 (Swift trigger #355942; Mangano et al., GCN #9585) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile).
  Observations started at 02:06 UT on June 29th, 2009, 4.8 hr after the burst and were performed under poor seeing conditions. In stacked images of 75 min total integration time in griz and 60 min in JHK, we do not detect any object within the enhanced XRT error circle (Goad et al., GCN #9590), down to the following limiting magnitudes (all in the AB system):

  g' > 23.7
  r' > 24.0
  i' > 23.0
  z' > 22.8
  J > 21.8
  H > 21.1
  K > 20.5
  

  These upper limits were derived using the GROND zeropoints and 2MASS field stars as reference and are not corrected for the Galactic foreground extinction corresponding to a reddening of E(B-V)=0.18 mag (Schlegel et al., 1998).
  We note the presence of a r'~23.5 mag source ~5 arcsec north east of the center of the enhanced XRT error circle, which given the large offset is very unlikely to be related to the GRB.
• GCN Circular #9593
  C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):
  Using the data set from T-240 to T+649 sec from recent telemetry downlinks, we report further analysis of BAT GRB 090628 (trigger #355942) (Mangano, et al., GCN Circ. 9585). The BAT ground-calculated position is RA, Dec = 237.038, -15.969 deg, which is

     RA(J2000)  =  15h 48m 09.0s 
     Dec(J2000) = -15d 58' 09.0" 
  

  with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 63%.
  The mask-weighted light curve shows a weak 1-sec wide precursor peak at ~T-7.5 sec that then returns almost to background levels, and the main peak starting at ~T-0.3 sec, peaking at ~T+1 sec, and ending at ~T+6 sec. T90 (15-350 keV) is 20.1 +- 4.6 sec (estimated error including systematics).
  The time-averaged spectrum from T-25.0 to T+4.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.36 +- 0.20. The fluence in the 15-150 keV band is 7.0 +- 0.8 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.05 sec in the 15-150 keV band is 1.5 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
  The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/355942/BA/
• GCN Circular #9594
  A. Moskvitin, O. Spiridonova, A. Valeev, T. Fatkhullin (SAO RAS, Niznijh Arkhyz, Russia), on behalf of a larger collaboration, report:
  We observed the field of GRB 090628 (Mangano et al., GCN #9585) in Rc band (14 x 60 seconds) with the Zeiss-1000 telescope of SAO RAS (Russia). The observations were carried out at high air mass. We did not detect any object within the enhanced XRT error circle (Goad et al., GCN #9590) down to the limiting magnitude 19.3 (according to nearby USNO-B1 stars). The average time of observations is 22:23:16 UT, 1.05 hours after the trigger.
  This message can be cited.
• GCN Circular #9596
  M. H. Siegel (PSU) and V. Mangano (INAF-IASFPA) report on behalf of the Swift/UVOT team.
  The Swift/UVOT began observing the field of GRB 090628 2790s after the BAT trigger (Mangano et al., GCN Circ. 9585). Data summed from the first orbit does not reveal a source at the refined position of the X-ray afterglow (Goad et al., GCN Circ. 9590).
  The 3-sigma upper limits for the finding chart (fc) and summed exposures are reported below:

  FILTER     T_start(s)  T_stop    Exposure     Mag/3UL
  =============================================================
  white fc     2791       2941        147       > 20.26
  white        3361       3560        196       > 20.72
  
  v            3771       3971        196       > 19.23
  
  b            3155       3355        196       > 20.16
  b            4591       4672         79       > 19.64
  
  u            2950       3149        196       > 19.63
  u            4386       4586        196       > 19.82
  
  uvw1         4181       4381        196       > 19.65
  
  uvm2         3976       4176        196       > 19.33
  
  uvw2         3566       3766        196       > 19.62
  =================================================================
  

  The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.05 (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627).
• GCN Circular #9599
  V. Mangano, B. Sbarufatti (INAF-IASF PA) report on behalf the Swift XRT Team:
  We have analyzed 19 ks of PC data of the candidate X-ray afterglow of GRB 090628 (Mangano et al, GCN Circ. 9585) spanning the time interval from T+2796 s to T+101.7 ks.
  The best position available for the source is the enhanced Swift-XRT position from Goad et al. (GCN Circ. 9590): RA, Dec = 237.05272, -15.98489 which is equivalent to

  RA (J2000): 15h 48m 12.65s
  Dec (J2000): -15d 59' 05.6"
  

  with an uncertainty of 1.9 arcsec (radius, 90% confidence).
  The 0.3-10 keV XRT light curve shows an initial flat or rising phase followed by a steep decay. The best fit with a broken power-law model is insensitive to the initial rise slope, of the order of 0.4, possibly consistent with zero, and provides a break at 14+/-4 ks after the trigger and a post-break decay slope of -1.3+/-0.3. The source is rather faint, and at this rate it will reach a level of 8.0e-4 counts/s at T+48 hours. All quoted errors are at the 90% confidence level.
  The average spectrum can be fitted by an absorbed power-law model with Cash statistics. Best fit spectral parameters are NH < 2.0e21 cm^-2 (consistent with Galactic absorption of 8.7e20 cm^-2, Kalberla et al. 2005) and photon index = 1.4 +/- 0.3 (Cstat(dof): 87.6(113)). The 0.3-10 keV observed(unabsorbed) average flux is 5.0e-13(5.5e-13) erg cm^-2 s^-1.
  The rate to flux conversion factor is 8.0e-11.
  The results of the XRT team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00355942
  This circular is an official product of the Swift-XRT team.
• GCN Report 226.1
  GCN_Report 226.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_226_1.pdf by V. Mangano at INAF IASF Pa titled: "Final Results on Swift GRB 090628"