Gamma-ray Burst 121226A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:10:11 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     544027,   Seg_Num: 0
  GRB_RA:          168.658d {+11h 14m 38s} (J2000),
                   168.816d {+11h 15m 16s} (current),
                   168.050d {+11h 12m 12s} (1950)
  GRB_DEC:         -30.414d {-30d 24' 51"} (J2000),
                   -30.485d {-30d 29' 06"} (current),
                   -30.142d {-30d 08' 29"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       4705 [cnts]    Image_Peak=149 [image_cnts]
  TRIGGER_DUR:     1.024 [sec] 
  TRIGGER_INDEX:   149     E_range: 25-100 keV
  BKG_INTEN:       29401 [cnts]
  BKG_TIME:        68965.97 SOD {19:09:25.97} UT
  BKG_DUR:         8 [sec]
  GRB_DATE:        16287 TJD;   361 DOY;   12/12/26
  GRB_TIME:        68983.89 SOD {19:09:43.89} UT
  GRB_PHI:         -14.69 [deg]
  GRB_THETA:        47.46 [deg]
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     15.68 [sigma]
  IMAGE_SIGNIF:    7.23 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +0  +2  -3  +0  +0  +3  +0 
  SUN_POSTN:       275.91d {+18h 23m 38s}  -23.33d {-23d 19' 32"}
  SUN_DIST:         91.82 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.81d {+05h 07m 13s}  +20.99d {+20d 59' 17"}
  MOON_DIST:       102.12 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      183.10,-32.14 [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 = 185.43,-16.80 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:11:33 UT
  NOTICE_TYPE:     Swift-XRT Nack-Position
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.649d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.415d {-30d 24' 51"} (J2000)
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69084.48 SOD {19:11:24.48} UT,   100.6 [sec] since BAT Trigger Time
  COUNTS:          2    Min_needed= 20
  STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
  PH2_ITER:        1    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:     Wed 26 Dec 12 19:13:26 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     544027,   Seg_Num: 0
  GRB_RA:          168.658d {+11h 14m 38s} (J2000),
                   168.816d {+11h 15m 16s} (current),
                   168.050d {+11h 12m 12s} (1950)
  GRB_DEC:         -30.414d {-30d 24' 51"} (J2000),
                   -30.485d {-30d 29' 06"} (current),
                   -30.142d {-30d 08' 29"} (1950)
  GRB_DATE:        16287 TJD;   361 DOY;   12/12/26
  GRB_TIME:        68983.89 SOD {19:09:43.89} UT
  TRIGGER_INDEX:   149
  GRB_PHI:         -14.69 [deg]
  GRB_THETA:        47.46 [deg]
  DELTA_TIME:      -31.00 [sec]
  TRIGGER_DUR:     1.024 [sec] 
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     15.68 [sigma]
  IMAGE_SIGNIF:    7.23 [sigma]
  LC_URL:          sw00544027000msb.lc
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 32"}
  SUN_DIST:         91.82 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.83d {+05h 07m 20s}  +20.99d {+20d 59' 17"}
  MOON_DIST:       102.09 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      183.10,-32.14 [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 = 185.43,-16.80 [deg].  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:14:25 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.649d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.415d {-30d 24' 52"} (J2000)
  POINT_ROLL:      118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69088.00 SOD {19:11:28.00} UT,   104.1 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        3.195
  N_STARS:         41
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        514 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1473 [pixels]
  DET_THRESH:      15
  PHOTO_THRESH:    8
  SL_URL:          sw00544027000msufc0104.fits
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 32"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.84d {+05h 07m 22s}  +20.99d {+20d 59' 18"}
  MOON_DIST:       102.08 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:14:59 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.649d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.415d {-30d 24' 52"} (J2000)
  POINT_ROLL:      118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69088.00 SOD {19:11:28.00} UT,   104.1 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        3.195
  N_STARS:         41
  X_OFFSET:        519 [pixels]
  Y_OFFSET:        514 [pixels]
  X_MAX:           1478 [pixels]
  Y_MAX:           1473 [pixels]
  DET_THRESH:      15
  PHOTO_THRESH:    8
  SL_URL:          sw00544027000msufc0104.fits
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 32"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.85d {+05h 07m 23s}  +20.99d {+20d 59' 18"}
  MOON_DIST:       102.08 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [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 26 Dec 12 19:15:56 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.649d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.415d {-30d 24' 52"} (J2000)
  ROLL:            118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69088.00 SOD {19:11:28.00} UT,   104.1 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     378241898
  X_OFFSET:        838 [pixels]
  Y_OFFSET:        833 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       998
  Y_GRB_POS:       993
  BINNING_INDEX:   1
  IM_URL:          sw00544027000msuni0115.fits
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.86d {+05h 07m 26s}  +20.99d {+20d 59' 18"}
  MOON_DIST:       102.07 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [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:     Wed 26 Dec 12 19:16:07 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.649d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.415d {-30d 24' 52"} (J2000)
  ROLL:            118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69088.00 SOD {19:11:28.00} UT,   104.1 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     378241898
  X_OFFSET:        838 [pixels]
  Y_OFFSET:        833 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       998
  Y_GRB_POS:       993
  BINNING_INDEX:   1
  IM_URL:          sw00544027000msuni0115.fits
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.86d {+05h 07m 26s}  +20.99d {+20d 59' 18"}
  MOON_DIST:       102.07 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.33, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:16:03 UT
  NOTICE_TYPE:     Swift-XRT Position
  TRIGGER_NUM:     544027,   Seg_Num: 0
  GRB_RA:          168.6412d {+11h 14m 33.88s} (J2000),
                   168.7993d {+11h 15m 11.82s} (current),
                   168.0335d {+11h 12m 08.04s} (1950)
  GRB_DEC:         -30.4073d {-30d 24' 26.2"} (J2000),
                   -30.4782d {-30d 28' 41.5"} (current),
                   -30.1346d {-30d 08' 04.7"} (1950)
  GRB_ERROR:       3.7 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       1.00e-10 [erg/cm2/sec]
  GRB_SIGNIF:      10.00 [sigma]
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69099.00 SOD {19:11:39.00} UT,   115.1 [sec] since BAT Trigger Time
  TAM[0-3]:        100.00 100.00 100.00 100.00
  AMPLIFIER:       1
  WAVEFORM:        31
  SUN_POSTN:       275.91d {+18h 23m 39s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.84 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.86d {+05h 07m 26s}  +20.99d {+20d 59' 18"}
  MOON_DIST:       102.06 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.31, 27.98 [deg] galactic lon,lat of the burst
  ECL_COORDS:      183.08,-32.14 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        TAM values, flux and significance fields are not valid.  
  COMMENTS:        This position was automatically generated on the ground using  
  COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
  COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
  COMMENTS:        The probability that this is a serendipitous source in the  
  COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:22:01 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.648d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.413d {-30d 24' 45"} (J2000)
  POINT_ROLL:      118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69300.53 SOD {19:15:00.53} UT,   316.6 [sec] since BAT Trigger Time
  FILTER:          7, U
  BKG_MEAN:        1.843
  N_STARS:         131
  X_OFFSET:        279 [pixels]
  Y_OFFSET:        274 [pixels]
  X_MAX:           1718 [pixels]
  Y_MAX:           1713 [pixels]
  DET_THRESH:      11
  PHOTO_THRESH:    6
  SL_URL:          sw00544027000msufc0316.fits
  SUN_POSTN:       275.92d {+18h 23m 41s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.91d {+05h 07m 38s}  +20.99d {+20d 59' 19"}
  MOON_DIST:       102.02 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.32, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:22:18 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.648d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.413d {-30d 24' 45"} (J2000)
  POINT_ROLL:      118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69300.53 SOD {19:15:00.53} UT,   316.6 [sec] since BAT Trigger Time
  FILTER:          7, U
  BKG_MEAN:        1.843
  N_STARS:         131
  X_OFFSET:        279 [pixels]
  Y_OFFSET:        274 [pixels]
  X_MAX:           1718 [pixels]
  Y_MAX:           1713 [pixels]
  DET_THRESH:      11
  PHOTO_THRESH:    6
  SL_URL:          sw00544027000msufc0316.fits
  SUN_POSTN:       275.92d {+18h 23m 41s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.91d {+05h 07m 39s}  +20.99d {+20d 59' 19"}
  MOON_DIST:       102.02 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.32, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [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 26 Dec 12 19:22:51 UT
  NOTICE_TYPE:     Swift-XRT Position UPDATE
  TRIGGER_NUM:     544027,   Seg_Num: 0
  GRB_RA:          168.6424d {+11h 14m 34.17s} (J2000),
                   168.8005d {+11h 15m 12.11s} (current),
                   168.0347d {+11h 12m 08.33s} (1950)
  GRB_DEC:         -30.4066d {-30d 24' 23.7"} (J2000),
                   -30.4775d {-30d 28' 39.0"} (current),
                   -30.1339d {-30d 08' 02.1"} (1950)
  GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       1.00e-10 [erg/cm2/sec]
  GRB_SIGNIF:      10.00 [sigma]
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69099.00 SOD {19:11:39.00} UT,   115.1 [sec] since BAT Trigger Time
  TAM[0-3]:        100.00 100.00 100.00 100.00
  AMPLIFIER:       1
  WAVEFORM:        31
  SUN_POSTN:       275.92d {+18h 23m 41s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.84 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.92d {+05h 07m 40s}  +20.99d {+20d 59' 19"}
  MOON_DIST:       102.01 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.32, 27.98 [deg] galactic lon,lat of the burst
  ECL_COORDS:      183.08,-32.14 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
  COMMENTS:        TAM values, flux and significance fields are not valid.  
  COMMENTS:        This position was automatically generated on the ground using  
  COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
  COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
  COMMENTS:        This position was enhanced using UVOT field astrometry.  
  COMMENTS:        The probability that this is a serendipitous source in the  
  COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 26 Dec 12 19:23:30 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.648d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.413d {-30d 24' 45"} (J2000)
  ROLL:            118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69300.53 SOD {19:15:00.53} UT,   316.6 [sec] since BAT Trigger Time
  FILTER:          7, U
  EXPOSURE_ID:     378242110
  X_OFFSET:        838 [pixels]
  Y_OFFSET:        833 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       998
  Y_GRB_POS:       993
  BINNING_INDEX:   1
  IM_URL:          sw00544027000msuni0327.fits
  SUN_POSTN:       275.92d {+18h 23m 41s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.92d {+05h 07m 42s}  +20.99d {+20d 59' 20"}
  MOON_DIST:       102.01 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.32, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [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:     Wed 26 Dec 12 19:23:40 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     544027,   Seg_Num: 0
  POINT_RA:        168.648d {+11h 14m 36s} (J2000)
  POINT_DEC:       -30.413d {-30d 24' 45"} (J2000)
  ROLL:            118.659d
  IMG_START_DATE:  16287 TJD;   361 DOY;   12/12/26
  IMG_START_TIME:  69300.53 SOD {19:15:00.53} UT,   316.6 [sec] since BAT Trigger Time
  FILTER:          7, U
  EXPOSURE_ID:     378242110
  X_OFFSET:        838 [pixels]
  Y_OFFSET:        833 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       998
  Y_GRB_POS:       993
  BINNING_INDEX:   1
  IM_URL:          sw00544027000msuni0327.fits
  SUN_POSTN:       275.92d {+18h 23m 41s}  -23.33d {-23d 19' 31"}
  SUN_DIST:         91.83 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
  MOON_POSTN:       76.92d {+05h 07m 42s}  +20.99d {+20d 59' 20"}
  MOON_DIST:       102.01 [deg]
  MOON_ILLUM:      98 [%]
  GAL_COORDS:      279.32, 27.98 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      183.09,-32.14 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN Circular #14105
  H. A. Krimm (CRESST/GSFC/USRA), J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), S. T. Holland (STScI), K. L. Page (U Leicester), T. Sakamoto (AGU), M. H. Siegel (PSU) and R. L. C. Starling (U Leicester) report on behalf of the Swift Team:
  At 19:09:43 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 121226A (trigger=544027). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 168.658, -30.414 which is

     RA(J2000) = 11h 14m 38s
     Dec(J2000) = -30d 24' 51"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak with a duration of about 2 sec. The peak count rate was ~2700 counts/sec (15-350 keV), at ~0 sec after the trigger. Although the duration of this burst is moderately short, it has a fairly soft spectrum. Therefore we must wait for further data to determine whether to classify GRB 121226A as a short or long burst.
  The XRT began observing the field at 19:11:24.4 UT, 100.6 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 168.6424, -30.4066 which is equivalent to:

     RA(J2000)  = 11h 14m 34.17s
     Dec(J2000) = -30d 24' 23.8"
  

  with an uncertainty of 2.2 arcseconds (radius, 90% containment). This location is 55 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
  A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (6.11 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 6.4 (+3.77/-3.06) x 10^21 cm^-2 (90% confidence).
  UVOT took a finding chart exposure of 150 seconds with the White filter starting 104 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 0.05.
  Burst Advocate for this burst is H. A. Krimm (krimm AT milkyway.gsfc.nasa.gov). 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 Circular #14106
  S. Guziy (Mykolaiv Nat. Univ.), O. Lara, R. Cunniffe, J. Gorosabel, M. Jelinek (IAA-CSIC), P. Kubanek (IP AS CR), Y. Fan, X. Zhao, J. Bai, C. Wang, Y. Xin (Yunnan Nacional Astronomical Observatory), Ch. Cui (Beijing National Astronomical Observatory) and A. J. Castro-Tirado (IAA-CSIC), on behalf of a larger collaboration, report:
  =93Following the detection of GRB 121226A by Swift (Krimm et al. GCNC 14105), the 0.6m BOOTES-4/MET robotic telescope at the Lijiang Astronomical Observatory (China) responded automatically to the trigger alert at 19:10:21 UT, 9 s after the GCN reception (i.e. 36 s after the onset of the event). After initial 0.5 s exposures, the first 19 unfiltered images (5 s exposure time each) starting 6 m 24 s postburst, show no optical afterglow at the refined XRT position down to 19th mag limiting magnitude (for the combined image). Observations are ongoing.=94
• GCN Circular #14107
  A. Klotz (IRAP-CNRS-OMP), D. Macpherson (UWA/ICRAR), D. Coward (UWA), B. Gendre (ASDC/INAF-OAR), M. Boer (UNS-CNRS-OCA), A. Williams (PO-UWA), R. Martin (PO-UWA) report:
  We imaged the field of GRB 121226A detected by SWIFT (trigger 544027) with the Zadko robotic telescope (D=100cm) located at the observatory - Gingin, Australia.
  The observations started 62.8s after the GRB trigger (38.6s after the notice). The elevation of the field increased from 64 degrees above horizon and weather conditions were good.
  The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT in the XRT error box with a limiting magnitude of: t0+62.8s to t0+122.8s : Rlim 17.5
  The second image is 30.0s exposure in tracking mode: t0+138s to t0+168s : Rlim 18.7
  We co-added a series of exposures: t0+138s to t0+335s : Rlim 19.4
  Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
  This message may be cited.
• GCN Circular #14108
  D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
  We observed the field of GRB 121226A (Krimm et al., GCNC 14105) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
  The observation started on 2012-12-26 19:11:59 UT (~2.3 min after the burst). We did not find any new point source within the XRT circle (Krimm et al., GCNC 14105) in all the three bands.
  Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration.

  T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
  ------------------------------------------------------
  0.04333    20:12:06    6360.0   >20.2  >20.2  >19.5
  ------------------------------------------------------
  T0+ : Elapsed time after the burst [day]
  T-EXP: Total Exposure time [sec]
  

• GCN Circular #14109
  V.K. Bhatt, S.B. Pandey and Brajesh Kumar ((ARIES Nainital, India, on behalf of larger Indian GRB collaboration)
  We observed GRB 121226A (Swift trigger 518731, Krimm et al. 2012, GCNC 14105) field with the 1.04m telescope at ARIES, Nainital starting at 2012-12-26 21:09:09 (UT). Several frames in R_c and I_c pass-bands, with an exposure time of 300 sec each, were obtained.
  Within the XRT error-circle, we do not detect any optical source down to following limiting magnitudes.

  Dec 26.9118 UT, 300sx4, I_c ~ 18.8 mag
  Dec 26.9292 UT, 300sx6, R_c ~ 19.5 mag
  

  The nearby USNO stars have been used for calibrate.
  This massage may be cited.
• GCN Circular #14110
  D. Xu (DARK/NBI), O. Smirnova, T. Purismo (NOT), J. P. U. Fynbo (DARK/NBI), P. Jakobsson (U. Iceland) report on behalf of a larger collaboration:
  We observed the field of GRB 121226A (Krimm et al., GCN 14105) using the 2.5m Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained 3x600s R-band and 3x360s z-band images with their median time of 06:14:49 UT on 2012-12-27 (i.e., 11.085 hr after the BAT trigger) and 06:53:54 UT (i.e., 11.736 hr post-trigger), respectively.
  No optical source was detected within the XRT error circle in both R-and z-bands, down to a 3sigma limit of R~23.0 mag ,calibrated with the USNO B1 catalogue.
• GCN Circular #14111
  W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
  Using the data set from T-61 to T+111 sec from the recent telemetry downlink, we report further analysis of BAT GRB 121226A (trigger #544027) (Krimm, et al., GCN Circ. 14105). The BAT ground-calculated position is RA, Dec = 168.620, -30.413 deg which is

      RA(J2000)  =  11h 14m 28.7s
      Dec(J2000) = -30d 24' 47.0"
  

  with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 35%. The mask-weighted light curve shows a single peak with duration approximately 1.5 seconds, with no sign of extended emission. T90 (15-350 keV) is 1.00 +- 0.20 sec (estimated error including systematics).
  The time-averaged spectrum from T-0.36 to T+0.80 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.51 +- 0.29. The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.21 sec in the 15-150 keV band is 1.6 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
  When plotting GRB 121226A on the T90-hardness diagram (see web link below), we see that it falls within the short-hard region of phase space, with T90 = 1.0 sec and Hardness ratio (energy fluence ratio 50-100 keV/25-50 keV) = 1.4. Therefore we now suggest that GRB 121226A should be classified as a short-hard burst. We do not have a lag analysis available at this time.
  The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/544027/BA/
• GCN Circular #14112
  O.M. Littlejohns (U. Leicester), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC), P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester) and H.A. Krimm report on behalf of the Swift-XRT team:
  We have analysed 10 ks of XRT data for GRB 121226A (Krimm et al. GCN Circ. 14105), from 109 s to 35.4 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The best available XRT position (using the promptly downlinked event data, the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue) is RA, Dec = 168.6423, -30.4064 which is equivalent to:

  RA (J2000): 11 14 34.14
  Dec(J2000): -30 24 23.1
  

  with an uncertainty of 2.1 arcsec (radius, 90% confidence).
  The light curve can be modelled with a power-law decay with a decay index of alpha=0.98 (+/-0.06).
  A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.4 (+/-0.4). The best-fitting absorption column is 8.2 (+2.5, -2.1) x 10^21 cm^-2, in excess of the Galactic value of 6.1 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.4 x 10^-11 (1.2 x 10^-10) erg cm^-2 count^-1.
  A summary of the PC-mode spectrum is thus:

  Total column:	     8.2 (+2.5, -2.1) x 10^21 cm^-2
  Galactic foreground: 6.1 x 10^20 cm^-2
  Excess significance: 6.0 sigma
  Photon index:	     2.4 (+/-0.4)
  

  If the light curve continues to decay with a power-law decay index of 0.98, the count rate at T+24 hours will be 1.5 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.7 x 10^-14 (1.9 x 10^-13) erg cm^-2 s^-1.
  The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00544027.
  This circular is an official product of the Swift-XRT team.
• GCN Circular #14113
  A. A. Breeveld (MSSL-UCL) and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of the Swift/UVOT team:
  The Swift/UVOT began settled observations of the field of GRB 121226A 104 s after the BAT trigger (Krimm et al., GCN Circ. 14105). No optical afterglow consistent with the XRT position (Littlejohns et al. GCN Circ. 14112) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:

  Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
  
  white_FC           104          254          147         >20.6
  u_FC               317          566          246         >19.6
  white              104        18160         1317         >21.6
  v                  646        10716         1121         >20.4
  b                  572        17397         1317         >21.3
  u                  317        16485         1544         >20.9
  w1                 696        12390         1163         >20.7
  m2                 671        11621         1298         >21.0
  w2                 622         6620          351         >20.2
  

  The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.055 in the direction of the burst (Schlegel et al. 1998).
• GCN Circular #14114
  A.J. Castro-Tirado, M. Jelinek, R. S=E1nchez-Ram=EDrez, J.C. Tello (IAA-CSIC), J.M. Gonz=E1lez-P=E9rez (GTC/IAC), S. Guziy (Mykolaiv Nat. Univ.), D. P=E9rez-Ram=EDrez (Univ. de Ja=E9n), P. Ferrero (IAC), J.M. Castro Cer=F3=n (ESAC), A. Fern=E1ndez-Soto (IFCA-UNICAN) and J. Gorosabel (IAA-CSIC), report:
  We have obtained deep r=92i=92z=92 images with the 10.4m GTC telescope at Observatorio del Roque de los Muchachos for GRB 121226A (Krimm et al. GCNC 14105; Baumgartner et al. GCNC 14111) starting on Dec 27.230--27.261 UT (i.e., 10.3--11.1 hr post burst). A faint object is detected at RA(J2000)=3D11:14:34.14, DEC(J2000)=3D-30:24:22.9 (0.7" error in each coordinate), consistent with the position of the X-ray afterglow (Littlejohns et al. GCNC 14112). The object shows a magnitude around r'~25. At this stage we cannot conclude whether this is the GRB 121226A optical afterglow or the underlying host galaxy.=94
• GCN Circular #14126
  W. Fong, B. A. Zauderer and E. Berger (Harvard) report:
  "We observed the position of the short-duration GRB 121226A (Krimm et al., GCN 14105; Baumgartner et al. GCN 14111) with the Karl G. Jansky Very Large Array (VLA) beginning on 2012 December 28.54 UT (1.75 days post-burst) at a mean frequency of 5.8 GHz. In 35-min on source, we detect a faint, 3-sigma radio source at:

  RA (J2000) = 11:14:34.12
  DEC (J2000) = -30:24:22.89
  

  with an uncertainty of ~0.2" in each coordinate.
  This position is coincident with the XRT and optical positions (Littlejohns et al., GCN 14112; Castro-Tirado et al., GCN 14114). Further observations are planned."
• GCN Circular #14139
  D. Malesani (DARK/NBI), P. D'Avanzo (INAF/OABr), A. Melandri (INAF/OABr), S. Covino (INAF/OABr), A. Fiorenzano (INAF/TNG), L. Di Fabrizio (INAF/TNG), and G. Andreuzzi (INAF/TNG) report on behalf of the CIBO collaboration:
  We observed the optical counterpart (Castro-Tirado et al., GCN 14114) of the short GRB 121226A (Krimm et al., GCN 14105) with the TNG telescope located in the Canary Islands. A total two hour exposure in the SDSS r filter was acquired, with mean time 2013 Jan 11.227 UT (15.4 days after the GRB). Sky conditions were good and the seeing was 1.1", despite the large airmass (around 2).
  Consistent with the position reported by Castro-Tirado et al. (GCN 14114) and Fong et al. (GCN 14126), we clearly detect an object with r(AB) = 24.68 +- 0.15. Photometric calibration was carried out by observing a standard field at similar airmass (for reference, we find r = 19.35 for the USNO star at RA = 11:14:33.12, Dec = -30:23:51.2). Coupled with the measurement by Castro-Tirado et al. (GCN 14114), obtained ~0.5 days after the GRB, our observation suggests that the object is the host galaxy of the GRB, with negligible afterglow contribution at both epochs. We note that the radio detection (Fong et al., GCN 14126) makes the association with the GRB secure.
  The coordinates of the object as measured in our image are (J2000, astrometry calibrated against USNO-B1):

  RA = 11:14:34.125
  Dec = -30:24:22.88
  

  with an estimated uncertainty of 0.3". We note the presence of two further, nearby objects, roughly 2" S and 4" NE of the optical/radio counterpart. A finding chart is available at the following URL:
  http://www.astro.ku.dk/~malesani/GRB/121226A/GRB121226A_finder_TNG.jpg
  
• photometric redshift z = 1.37 +0.05 -0.06
  of host-galaxy: A. E. Nugent et al. 2022, ApJ, 940, 57