Gamma-ray Burst 060111

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:23:18 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     176818,   Seg_Num: 0
  GRB_RA:          276.212d {+18h 24m 51s} (J2000),
                   276.264d {+18h 25m 03s} (current),
                   275.785d {+18h 23m 08s} (1950)
  GRB_DEC:         +37.602d {+37d 36' 08"} (J2000),
                   +37.606d {+37d 36' 21"} (current),
                   +37.573d {+37d 34' 23"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       2953 [cnts]    Image_Peak=149 [image_cnts]
  TRIGGER_DUR:     0.512 [sec] 
  TRIGGER_INDEX:   124     E_range: 25-100 keV
  BKG_INTEN:       35747 [cnts]
  BKG_TIME:        15775.05 SOD {04:22:55.05} UT
  BKG_DUR:         8 [sec]
  GRB_DATE:        13746 TJD;    11 DOY;   06/01/11
  GRB_TIME:        15786.12 SOD {04:23:06.12} UT
  GRB_PHI:         -34.11 [deg]
  GRB_THETA:        17.98 [deg]
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     13.49 [sigma]
  IMAGE_SIGNIF:    7.47 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +0  +2 +12  +0  +0 -47  +1 
  SUN_POSTN:       292.49d {+19h 29m 57s}  -21.83d {-21d 49' 43"}
  SUN_DIST:         61.36 [deg]
  MOON_POSTN:       72.03d {+04h 48m 07s}  +27.07d {+27d 04' 20"}
  MOON_DIST:       111.44 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      280.13, 60.82 [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 found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        This trigger occurred at longitude,latitude = 148.61,7.12 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:24:43 UT
  NOTICE_TYPE:     Swift-XRT Image
  TRIGGER_NUM:     176818,   Seg_Num: 0
  GRB_RA:          276.2040d {+18h 24m 48.9s} (J2000),
                   276.2555d {+18h 25m 01.3s} (current),
                   275.7766d {+18h 23m 06.3s} (1950)
  GRB_DEC:         +37.6059d {+37d 36' 21.2"} (J2000),
                   +37.6095d {+37d 36' 34.3"} (current),
                   +37.5768d {+37d 34' 36.6"} (1950)
  GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
  GRB_INTEN:       45 [cnts]
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15852.14 SOD {04:24:12.14} UT,   66.0 [sec] since BAT Trigger Time
  CENTROID_X:      299.43,  raw= 299  [pixels]
  CENTROID_Y:      284.04,  raw= 284  [pixels]
  ROLL:            162.79 [deg]
  GAIN:            1
  MODE:            3, Long Image mode
  WAVEFORM:        134
  EXPO_TIME:       2.50 [sec]
  GRB_POS_XRT_Y:   -37.75
  GRB_POS_XRT_Z:   1.18
  IMAGE_URL:       sw00176818000msxim.img
  SUN_POSTN:       292.49d {+19h 29m 57s}  -21.83d {-21d 49' 43"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.04d {+04h 48m 10s}  +27.07d {+27d 04' 27"}
  MOON_DIST:       111.44 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.10 [deg] galactic lon,lat of the burst
  ECL_COORDS:      280.12, 60.83 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Image.  
  COMMENTS:        WARNING: XRT alignment calibration is on-going, and there may be  
  COMMENTS:        residual systematic offsets of several arcseconds not accounted for yet  
  COMMENTS:        by our on-board position determination algorithm.  We have increased  
  COMMENTS:        the estimated error circle radius to take this into account.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:24:43 UT
  NOTICE_TYPE:     Swift-XRT Position
  TRIGGER_NUM:     176818,   Seg_Num: 0
  GRB_RA:          276.2040d {+18h 24m 48.9s} (J2000),
                   276.2555d {+18h 25m 01.3s} (current),
                   275.7766d {+18h 23m 06.3s} (1950)
  GRB_DEC:         +37.6059d {+37d 36' 21.2"} (J2000),
                   +37.6095d {+37d 36' 34.3"} (current),
                   +37.5768d {+37d 34' 36.6"} (1950)
  GRB_ERROR:       5.8 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       8.06e-10 [erg/cm2/sec]
  GRB_SIGNIF:      6.70 [sigma]
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15852.14 SOD {04:24:12.14} UT,   66.0 [sec] since BAT Trigger Time
  TAM[0-3]:        327.65 237.18 261.22 243.02
  AMPLIFIER:       2
  WAVEFORM:        134
  SUN_POSTN:       292.49d {+19h 29m 57s}  -21.83d {-21d 49' 43"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.04d {+04h 48m 10s}  +27.07d {+27d 04' 27"}
  MOON_DIST:       111.44 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.10 [deg] galactic lon,lat of the burst
  ECL_COORDS:      280.12, 60.83 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        WARNING: XRT alignment calibration is on-going, and there may be  
  COMMENTS:        residual systematic offsets of several arcseconds not accounted for yet  
  COMMENTS:        by our on-board position determination algorithm.  We have increased  
  COMMENTS:        the estimated error circle radius to take this into account.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:25:07 UT
  NOTICE_TYPE:     Swift-XRT Processed Image
  TRIGGER_NUM:     176818,   Seg_Num: 0
  GRB_RA:          276.2040d {+18h 24m 48.9s} (J2000),
                   276.2555d {+18h 25m 01.3s} (current),
                   275.7766d {+18h 23m 06.3s} (1950)
  GRB_DEC:         +37.6059d {+37d 36' 21.2"} (J2000),
                   +37.6095d {+37d 36' 34.3"} (current),
                   +37.5768d {+37d 34' 36.6"} (1950)
  GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
  GRB_INTEN:       45 [cnts]
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15852.14 SOD {04:24:12.14} UT,   66.0 [sec] since BAT Trigger Time
  CENTROID_X:      299.43,  raw= 299  [pixels]
  CENTROID_Y:      284.04,  raw= 284  [pixels]
  ROLL:            162.79 [deg]
  GAIN:            1
  MODE:            3, Long Image mode
  WAVEFORM:        134
  EXPO_TIME:       2.50 [sec]
  GRB_POS_XRT_Y:   -37.75
  GRB_POS_XRT_Z:   1.18
  IMAGE_URL:       sw00176818000msxim.img
  SUN_POSTN:       292.49d {+19h 29m 57s}  -21.83d {-21d 49' 43"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.05d {+04h 48m 11s}  +27.07d {+27d 04' 29"}
  MOON_DIST:       111.44 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.10 [deg] galactic lon,lat of the burst
  ECL_COORDS:      280.12, 60.83 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Processed Image.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:26:46 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     176818,   Seg_Num: 0
  GRB_RA:          276.212d {+18h 24m 51s} (J2000),
                   276.264d {+18h 25m 03s} (current),
                   275.785d {+18h 23m 08s} (1950)
  GRB_DEC:         +37.602d {+37d 36' 08"} (J2000),
                   +37.606d {+37d 36' 21"} (current),
                   +37.573d {+37d 34' 23"} (1950)
  GRB_DATE:        13746 TJD;    11 DOY;   06/01/11
  GRB_TIME:        15786.12 SOD {04:23:06.12} UT
  TRIGGER_INDEX:   124
  GRB_PHI:         -34.11 [deg]
  GRB_THETA:        17.98 [deg]
  DELTA_TIME:      12.00 [sec]
  TRIGGER_DUR:     0.512 [sec] 
  LC_URL:          sw00176818000msb.lc
  SUN_POSTN:       292.49d {+19h 29m 58s}  -21.83d {-21d 49' 42"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.06d {+04h 48m 15s}  +27.08d {+27d 04' 38"}
  MOON_DIST:       111.45 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      280.13, 60.82 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Lightcurve.  
  COMMENTS:           
  COMMENTS:        The next comments were copied from the BAT_POS Notice:  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        This trigger occurred at longitude,latitude = 148.61,7.12 [deg].  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:29:36 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.214d {+18h 24m 51s} (J2000)
  POINT_DEC:       +37.608d {+37d 36' 31"} (J2000)
  POINT_ROLL:      162.786d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15857.78 SOD {04:24:17.78} UT,   71.7 [sec] since BAT Trigger Time
  FILTER:          3, V
  BKG_MEAN:        1.536
  N_STARS:         91
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        616 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1575 [pixels]
  DET_THRESH:      10
  PHOTO_THRESH:    5
  SL_URL:          sw00176818000msufc0071.fits
  SUN_POSTN:       292.49d {+19h 29m 58s}  -21.83d {-21d 49' 41"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.09d {+04h 48m 22s}  +27.08d {+27d 04' 52"}
  MOON_DIST:       111.45 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.13, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:30:15 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.214d {+18h 24m 51s} (J2000)
  POINT_DEC:       +37.608d {+37d 36' 31"} (J2000)
  POINT_ROLL:      162.786d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15857.78 SOD {04:24:17.78} UT,   71.7 [sec] since BAT Trigger Time
  FILTER:          3, V
  BKG_MEAN:        1.536
  N_STARS:         91
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        616 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1575 [pixels]
  DET_THRESH:      10
  PHOTO_THRESH:    5
  SL_URL:          sw00176818000msufc0071.fits
  SUN_POSTN:       292.49d {+19h 29m 58s}  -21.83d {-21d 49' 41"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.10d {+04h 48m 23s}  +27.08d {+27d 04' 55"}
  MOON_DIST:       111.45 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.13, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Source List.  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:30:54 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.214d {+18h 24m 51s} (J2000)
  POINT_DEC:       +37.608d {+37d 36' 31"} (J2000)
  ROLL:            162.786d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15857.78 SOD {04:24:17.78} UT,   71.7 [sec] since BAT Trigger Time
  FILTER:          3, V
  EXPOSURE_ID:     158646258
  X_OFFSET:        839 [pixels]
  Y_OFFSET:        936 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       999
  Y_GRB_POS:       1096
  BINNING_INDEX:   1
  IM_URL:          sw00176818000msuni0071.fits
  SUN_POSTN:       292.49d {+19h 29m 59s}  -21.83d {-21d 49' 41"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.10d {+04h 48m 25s}  +27.08d {+27d 04' 58"}
  MOON_DIST:       111.45 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.13, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Image.  
  COMMENTS:        The GRB Position came from the XRT Position Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:31:21 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.214d {+18h 24m 51s} (J2000)
  POINT_DEC:       +37.608d {+37d 36' 31"} (J2000)
  ROLL:            162.786d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  15857.78 SOD {04:24:17.78} UT,   71.7 [sec] since BAT Trigger Time
  FILTER:          3, V
  EXPOSURE_ID:     158646258
  X_OFFSET:        839 [pixels]
  Y_OFFSET:        936 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       999
  Y_GRB_POS:       1096
  BINNING_INDEX:   1
  IM_URL:          sw00176818000msuni0071.fits
  SUN_POSTN:       292.49d {+19h 29m 59s}  -21.83d {-21d 49' 40"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.11d {+04h 48m 26s}  +27.08d {+27d 05' 00"}
  MOON_DIST:       111.45 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.43, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.13, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Image.  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:40:06 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.216d {+18h 24m 52s} (J2000)
  POINT_DEC:       +37.610d {+37d 36' 37"} (J2000)
  POINT_ROLL:      162.789d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  16064.58 SOD {04:27:44.58} UT,   278.5 [sec] since BAT Trigger Time
  FILTER:          9, B
  BKG_MEAN:        3.733
  N_STARS:         83
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        616 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1575 [pixels]
  DET_THRESH:      16
  PHOTO_THRESH:    9
  SL_URL:          sw00176818000msufc0278.fits
  SUN_POSTN:       292.50d {+19h 30m 00s}  -21.83d {-21d 49' 37"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.19d {+04h 48m 46s}  +27.10d {+27d 05' 44"}
  MOON_DIST:       111.46 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.44, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.14, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 11 Jan 06 04:40:31 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     176818,   Seg_Num: 0
  POINT_RA:        276.216d {+18h 24m 52s} (J2000)
  POINT_DEC:       +37.610d {+37d 36' 37"} (J2000)
  POINT_ROLL:      162.789d
  IMG_START_DATE:  13746 TJD;    11 DOY;   06/01/11
  IMG_START_TIME:  16064.58 SOD {04:27:44.58} UT,   278.5 [sec] since BAT Trigger Time
  FILTER:          9, B
  BKG_MEAN:        3.733
  N_STARS:         83
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        616 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1575 [pixels]
  DET_THRESH:      16
  PHOTO_THRESH:    9
  SL_URL:          sw00176818000msufc0278.fits
  SUN_POSTN:       292.50d {+19h 30m 00s}  -21.83d {-21d 49' 37"}
  SUN_DIST:         61.37 [deg]
  MOON_POSTN:       72.20d {+04h 48m 47s}  +27.10d {+27d 05' 46"}
  MOON_DIST:       111.46 [deg]
  MOON_ILLUM:      90 [%]
  GAL_COORDS:       65.44, 21.09 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      280.14, 60.83 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Source List.  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN Circular #4479
  S. Zane (MSSL-UCL), S. Barthelmy (GSFC), A. Beardmore (U Leicester), A. J. Blustin (UCL-MSSL), D. Burrows (PSU), J. Cummings (GSFC/NRC), N. Gehrels (GSFC), M. Goad (U Leicester), J. Kennea (PSU), C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL) on behalf of the Swift team:
  At 04:23:06 UT, Swift-BAT triggered and located GRB 060111 (trigger=176818). The spacecraft slewed immediately. The BAT on-board calculated location is RA,Dec 276.212d,+37.602d {18h 24m 51s,+37d 36' 08"} (J2000), with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys). The BAT light curve shows a single peak structure with a total duration of ~20 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~5 sec after the trigger.
  The XRT began observing the field at 04:24:12 UT (66 sec after the burst). The instrument found a bright, variable, uncataloged X-ray source located at:

  RA(J2000) = 18h 24m 48.9s
  Dec(J2000) = +37d 36' 21"
  

  This location is 27.4 arcseconds from the BAT position. The estimated uncertainty is 8 arcseconds (90% confidence radius), including about 5 arcseconds systematic error due to an XRT boresight offset not currently corrected on-board. The initial flux was 8E-10 ergs/cm2/s (0.2-10 keV).
  UVOT took a finding chart exposure of 200 seconds with the V filter starting 72 seconds after the BAT trigger. No 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 18th 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 18.0 mag. No correction has been made for the expected visual extinction of about 0.1 magnitudes.
  We are currently in the portion of the orbits where the spacecraft does not pass over the Malindi downlink station. Therefore, it will be at least 7 hours before we have access to the full data set for the refined analyses.
• GCN Circular #4480
  F. Yuan (U Mich), W. Rujopakarn (U Mich), E.S. Rykoff (U Mich), S.A. Yost (U Mich), report on behalf of the ROTSE collaboration:
  ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, Turkey, responded to GRB 060111 (Swift trigger 176818), producing images beginning 5 s after the GCN notice time. An automated response took the first image at 04:23:23.2 UT, 17.1 s after the burst, under twilight conditions. We took 10 5-sec eposures before the individual images were saturated due to twilight. These unfiltered images are calibrated relative to USNO A2.0 (R).
  Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma error circle and particularly at the XRT position, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 13.4-13.8; we set the following specific limits.

  start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
  --------------------------------------------------------------------
  04:23:23.2   04:23:28.2         5     13.4           17.1       N
  04:23:23.2   04:25:31.0     127.8     14.5           17.1       Y
  

  s
• GCN Circular #4481
  M.R. Goad, A.P. Beardmore, K. Page (U. Leicester), D. Burrows (PSU), R. Fink (GSFC), M. Ajello (MPE) report on behalf of the Swift XRT team.
  From analysis of 2.5 ks of Photon Counting mode data of GRB060111 (Zane et al., GCN 4479) starting in the 2nd orbit of observations, we obtain a refined XRT position of RA: 18h 24m 49.0s, Dec:+37d 36m 16.1s (J2000) with an uncertainty of 3.6 arcsec (90% containment). This includes the latest XRT boresight correction. This refined position is 25.1 arcsec from the BAT on-board position and 5 arcsec from the XRT on-board position quoted in GCN 4479.
  We have also analysed 400 s of XRT Windowed Timing mode observations starting 78 s after the BAT trigger. The XRT lightcurve displays 3 large flares with a peak count rate of approximately 150 ct/s occurring 280 s after the BAT trigger. The light-curve has an underlying powerlaw decay of slope -1.3.
  The XRT WT mode 0.3-10 keV spectrum is well represented by an absorbed powerlaw with photon index 2.35 +/-0.04 with a mean unabsorbed flux of 2.5e-9 ergs/cm2/s. We find evidence for excess NH of 2.4e21 cm^-2.
  The predicted 0.3-10 keV unabsorbed flux 24 hours after the BAT trigger is 1.2e-13 ergs/cm2/s
• GCN Circular #4482
  A. J. Blustin (UCL-MSSL), S. Zane (UCL-MSSL), S. R. Rosen (UCL-MSSL) on behalf of the Swift/UVOT team
  Further analysis of the initial UVOT data for GRB 060111 (Zane et al., GCN 4479) reveals a potential afterglow candidate at
  RA,Dec (J2000) = 18:24:49.132 +37:36:14.47
  within the refined XRT error circle (Goad et al., GCN 4481). The source, significant at 8 sigma in an 3 arcsec radius aperture, has a V band magnitude of 18.9 +/- 0.4 in a 200 s exposure starting at 72 s after the BAT trigger. This magnitude is uncorrected for Galactic extinction (E(B-V) ~0.1).
• GCN Circular #4483
  Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
  We imaged the field of GRB 060511 detected by SWIFT (trigger 176818) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
  First image was acquired 20s after the GCN trigger (7s after the notice). The field elevation increased from 23 degrees above horizon and weather conditions were good. Moon was just rising (23 deg from the field) at the begining of observations. Due to a technical problem, there was no image between 261 and 510s after the trigger.
  We detected no new source comparing our individual unfiltered images with the USNO-B1 catalog within the error circle at the XRT position (Goad et al. GCNC 4481).
  From individual frames we give early limits:

  Day : 2006-01-11
  UT-start      UT-end      (sec since GRB)  Exp(s)  R-mag
  04:23:25.7  - 04:24.25.7    20 -   80        60   >16.2 (one frame trailed)
  04:24:32.4  - 04:25.02.4    86 -  116        30   >17.0 (one frame)
  04:25:08.7  - 04:25.38.7   122 -  152        30   >17.0 (one frame)
  04:31:36.2  - 04:33:06.2   510 -  600        90   >17.7 (one frame)
  

  To increase the signal to noise, we co-added series frames. The source at the XRT position (Goad et al. GCNC 4481) is marginaly detected on the first co-addition:

  Day : 2006-01-11
  UT-start      UT-end      (sec since GRB)  R-mag
  04:24:32   - 04:27.27      86 -   261      ~18.3 (sum of 5 frames of 30s)
  04:31:36   - 04:40.13     510 -  1027      >18.7 (sum of 6 frames of 90s)
  

  Magnitudes were estimated with the nearby USNO-B1 stars.
  This message may be cited.
• GCN Circular #4485
  V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, G.Borisov, A.Sankovich, G.Antipov, V.Vladimirov
  Sternberg Astronomical Institute, Moscow Union 'Optic'
  MASTER robotic system (http://observ.pereplet.ru) responded to GRB060111.2 (GRB_TIME is 2006-01-11 04:23:06.12). The first image was at 2006-01-11 04:25:16 UT, 130 s after the GRB time (a half of an hour befor sunrise). The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). The robot not find OT-candidate in error box. Our final results on OT magnitude limit are:

    UT (start)    Mean time     After GRB time      m          exptime
  
       04 25 16   04 25 31        130 s            16.0         30 sec
  

  The first JPG-image will be available at http://observ.pereplet.ru/images/GRB060111.2/1.jpg This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru
• GCN Circular #4486
  G. Sato (ISAS), L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), A. Smale (NASA HQ), J. Tueller (GSFC), on behalf of the Swift-BAT team:
  Using the data set from T-299 to T+303.0 sec from the recent telemetry downlink, we report further analysis of BAT GRB 060111 (trigger #176818) (Zane, et al., GCN 4479). The BAT ground-calculated position is (RA,Dec) = 276.195, 37.596 {18h 24m 47.3s, 37d 35' 44.1"} (deg; J2000) +- 0.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 98%.
  The light curve is a single peak, rise slightly faster than its decay. T90 (15-350 keV) is (13 +- 1) sec (estimated error including systematics). There is a small bump of marginal significance in the 15-50 keV band at T+280, the time of the x-ray flare observed by the XRT (GCN circ. #4481, Goad et al.).
  The time-averaged spectrum from T-0.7 to T+14.7 is best fit by a cut-off power law with an Epeak of (72 +14, -8) keV and a photon index of 0.8 +- 0.3. The fluence in the 15-150 keV band is (1.18 +- 0.05) x 10^-06 erg/cm2. A simple power law also gives an acceptable fit, with a photon index of 1.63 +/- 0.07 and a fluence of (1.25 +- 0.05) x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+4.3 sec in the 15-150 keV band is (1.72 +- 0.15) ph/cm2/sec. All the quoted errors are at the 90% confidence level.
• GCN Circular #4490
  S. B. Cenko, A. M. Soderberg, E. Ofek (Caltech) and D. B. Fox (Penn State) report on behalf of the Caltech-NRAO-Carnegie Collaboration:
  We have imaged the field of GRB 060111(a) (Zane et al., GCN 4479) with the automated Palomar 60-inch telescope. Observations consisted of 9 x 180 s exposures in the Kron R-band taken at a mean epoch of 13:19:49 11 January UT (~ 8.9 hours after the burst trigger).
  We find no sources in the revised XRT error circle (Goad et al., GCN 4481) or at the location of the proposed UVOT counterpart (Blustin, Zane, and Rosen, GCN 4482). The limiting magnitude of our observations, calculated with respect to several Guide Star Catalog sources in the field, is R > 20.5.
• GCN Circular #4494
  I. Khamitov, K. Uluc, Z. Aslan (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.), T. Saygac, O. Onal (Ist. Uni.) R. Burenin, M. Pavlinsky, R. Sunyaev (IKI) I. Bikmaev, N. Sakhibullin (KSU/AST)
  report:
  We observed field around of possible optical counterpart (Blustin et al., GCN4482) of GRB060111A (Swift trigger 176818) with Russian-Turkish 1.5-m telescope (RTT150, Bakyrlytepe, TUBITAK National Observatory, Turkey), starting on Jan. 12, 03:37UT, i.e. ~23.2 hours after the burst.
  A series of frames (8*300s exposures in R band) were taken. The afterglow candidate was detected only marginally near the detection limit of our combined image, which is estimated as R~23.2 (photometry is USNO-B1 calibrated). We also note that at about 5 arcsec from the OT we detected an extended source whith R=21.75+/-0.1, which may be a host galaxy of the GRB. The coordinates of this galaxy are RA= 18h24m49.01s (J2000.0) DEC=+37d36'09."6 (J2000.0).
  The finding chart can be found at: http://www.tug.tubitak.gov.tr/~irekk/grb/grb060111a/grb060111A.JPG
  Also we have to do a correction to GCN4493: We detected extended source in direction to SE, not NW. The upper limit for the GRB060111B OT is also actually deeper: R=~23.6 (the difference is due to corrected error in photometric calibration).
  This message may be cited.
  
• GCN Circular #4497
  S. R. Rosen (UCL-MSSL), S. Zane (UCL-MSSL), A. J. Blustin (UCL-MSSL), K. Hurley (Berkeley), M. Chester (PSU), N. Gehrels (GSFC) on behalf of the Swift/UVOT team
  Further analysis of the Swift/UVOT data for GRB 060111A (Zane et al., GCN 4479) reveals that the afterglow candidate reported by Blustin et al. (GCN 4482) in the initial UVOT V-band exposure has faded from view in subsequent data. The 3 sigma magnitude upper limits from later summed images in the different filters are as follows:

  Filter   T_range(s)  Exp(s)  3sigUL(mag)
  
  V        3750-4105   59      18.5
  V        4757-10346  472     19.6
  
  B        280-17141   1746    21.2
  U        6042-16227  1476    20.8
  W1       5838-21553  1033    20.3
  M2       5633-10550  572     20.1
  W2       9942-12104  435     20.1
  

  These magnitudes are uncorrected for Galactic extinction.
• D. Perley's Keck GRB Host project: suggests potential host galaxy at z=2.32 (Ly-alpha). The nearby galaxy is at z=0.17 (OII, CaHK, OIII, Halpha).