Gamma-ray Burst 110112A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:12:41 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     442039,   Seg_Num: 0
GRB_RA:          329.941d {+21h 59m 46s} (J2000),
                 330.067d {+22h 00m 16s} (current),
                 329.370d {+21h 57m 29s} (1950)
GRB_DEC:         +26.489d {+26d 29' 20"} (J2000),
                 +26.542d {+26d 32' 31"} (current),
                 +26.249d {+26d 14' 55"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       2166 [cnts]    Image_Peak=122 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   433     E_range: 15-50 keV
BKG_INTEN:       28665 [cnts]
BKG_TIME:        15121.44 SOD {04:12:01.44} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15573 TJD;    12 DOY;   11/01/12
GRB_TIME:        15138.46 SOD {04:12:18.46} UT
GRB_PHI:         147.60 [deg]
GRB_THETA:        18.95 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.12 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
MERIT_PARAMS:     +1  +0  +0  -1  +1  -3  +0  +0 -50  +0 
SUN_POSTN:       293.33d {+19h 33m 20s}  -21.71d {-21d 42' 19"}
SUN_DIST:         59.94 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.86d {+00h 59m 27s}  +11.84d {+11d 50' 38"}
MOON_DIST:        44.52 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.72,-22.33 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      343.20, 35.98 [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 = 186.33,12.24 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:13:40 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.934d {+21h 59m 44s} (J2000)
POINT_DEC:       +26.484d {+26d 29' 04"} (J2000)
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15213.91 SOD {04:13:33.91} UT,   75.5 [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:     Wed 12 Jan 11 04:15:58 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     442039,   Seg_Num: 0
GRB_RA:          329.941d {+21h 59m 46s} (J2000),
                 330.067d {+22h 00m 16s} (current),
                 329.370d {+21h 57m 29s} (1950)
GRB_DEC:         +26.489d {+26d 29' 20"} (J2000),
                 +26.542d {+26d 32' 31"} (current),
                 +26.249d {+26d 14' 55"} (1950)
GRB_DATE:        15573 TJD;    12 DOY;   11/01/12
GRB_TIME:        15138.46 SOD {04:12:18.46} UT
TRIGGER_INDEX:   433
GRB_PHI:         147.60 [deg]
GRB_THETA:        18.95 [deg]
DELTA_TIME:      57.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.12 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
LC_URL:          sw00442039000msb.lc
SUN_POSTN:       293.33d {+19h 33m 20s}  -21.71d {-21d 42' 17"}
SUN_DIST:         59.94 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.89d {+00h 59m 33s}  +11.85d {+11d 51' 13"}
MOON_DIST:        44.54 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.72,-22.33 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      343.20, 35.98 [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 = 186.33,12.24 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:16:38 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.934d {+21h 59m 44s} (J2000)
POINT_DEC:       +26.484d {+26d 29' 03"} (J2000)
POINT_ROLL:      219.848d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15219.33 SOD {04:13:39.33} UT,   80.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.364
N_STARS:         190
X_OFFSET:        403 [pixels]
Y_OFFSET:        560 [pixels]
X_MAX:           1362 [pixels]
Y_MAX:           1519 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00442039000msufc0080.fits
SUN_POSTN:       293.34d {+19h 33m 20s}  -21.71d {-21d 42' 17"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.89d {+00h 59m 35s}  +11.86d {+11d 51' 20"}
MOON_DIST:        44.55 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:17:01 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.934d {+21h 59m 44s} (J2000)
POINT_DEC:       +26.484d {+26d 29' 03"} (J2000)
POINT_ROLL:      219.848d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15219.33 SOD {04:13:39.33} UT,   80.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.364
N_STARS:         190
X_OFFSET:        403 [pixels]
Y_OFFSET:        560 [pixels]
X_MAX:           1362 [pixels]
Y_MAX:           1519 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00442039000msufc0080.fits
SUN_POSTN:       293.34d {+19h 33m 21s}  -21.70d {-21d 42' 17"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.90d {+00h 59m 35s}  +11.86d {+11d 51' 24"}
MOON_DIST:        44.55 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 12 Jan 11 04:17:41 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     442039,   Seg_Num: 0
GRB_RA:          329.9322d {+21h 59m 43.72s} (J2000),
                 330.0582d {+22h 00m 13.97s} (current),
                 329.3613d {+21h 57m 26.71s} (1950)
GRB_DEC:         +26.4568d {+26d 27' 24.4"} (J2000),
                 +26.5100d {+26d 30' 35.9"} (current),
                 +26.2166d {+26d 12' 59.6"} (1950)
GRB_ERROR:       4.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15225.00 SOD {04:13:45.00} UT,   86.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       293.34d {+19h 33m 21s}  -21.70d {-21d 42' 17"}
SUN_DIST:         59.91 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.90d {+00h 59m 37s}  +11.86d {+11d 51' 32"}
MOON_DIST:        44.55 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.69,-22.35 [deg] galactic lon,lat of the burst
ECL_COORDS:      343.17, 35.96 [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 12 Jan 11 04:18:02 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.934d {+21h 59m 44s} (J2000)
POINT_DEC:       +26.484d {+26d 29' 03"} (J2000)
ROLL:            219.848d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15219.33 SOD {04:13:39.33} UT,   80.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     316498425
X_OFFSET:        722 [pixels]
Y_OFFSET:        879 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       1039
BINNING_INDEX:   1
IM_URL:          sw00442039000msuni0087.fits
SUN_POSTN:       293.34d {+19h 33m 21s}  -21.70d {-21d 42' 16"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.91d {+00h 59m 37s}  +11.86d {+11d 51' 35"}
MOON_DIST:        44.55 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 12 Jan 11 04:18:19 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.934d {+21h 59m 44s} (J2000)
POINT_DEC:       +26.484d {+26d 29' 03"} (J2000)
ROLL:            219.848d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15219.33 SOD {04:13:39.33} UT,   80.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     316498425
X_OFFSET:        722 [pixels]
Y_OFFSET:        879 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       1039
BINNING_INDEX:   1
IM_URL:          sw00442039000msuni0087.fits
SUN_POSTN:       293.34d {+19h 33m 21s}  -21.70d {-21d 42' 16"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.91d {+00h 59m 38s}  +11.86d {+11d 51' 39"}
MOON_DIST:        44.56 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 12 Jan 11 04:25:15 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.930d {+21h 59m 43s} (J2000)
POINT_DEC:       +26.485d {+26d 29' 05"} (J2000)
POINT_ROLL:      219.846d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15431.73 SOD {04:17:11.73} UT,   293.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.962
N_STARS:         190
X_OFFSET:        163 [pixels]
Y_OFFSET:        320 [pixels]
X_MAX:           1602 [pixels]
Y_MAX:           1759 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00442039000msufc0293.fits
SUN_POSTN:       293.34d {+19h 33m 22s}  -21.70d {-21d 42' 14"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.96d {+00h 59m 51s}  +11.88d {+11d 52' 53"}
MOON_DIST:        44.60 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:25:43 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     442039,   Seg_Num: 0
GRB_RA:          329.9329d {+21h 59m 43.89s} (J2000),
                 330.0589d {+22h 00m 14.14s} (current),
                 329.3620d {+21h 57m 26.88s} (1950)
GRB_DEC:         +26.4563d {+26d 27' 22.6"} (J2000),
                 +26.5095d {+26d 30' 34.1"} (current),
                 +26.2161d {+26d 12' 57.8"} (1950)
GRB_ERROR:       2.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15225.00 SOD {04:13:45.00} UT,   86.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       293.34d {+19h 33m 22s}  -21.70d {-21d 42' 13"}
SUN_DIST:         59.91 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.97d {+00h 59m 52s}  +11.88d {+11d 52' 58"}
MOON_DIST:        44.59 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.69,-22.35 [deg] galactic lon,lat of the burst
ECL_COORDS:      343.17, 35.96 [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 12 Jan 11 04:25:38 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.930d {+21h 59m 43s} (J2000)
POINT_DEC:       +26.485d {+26d 29' 05"} (J2000)
POINT_ROLL:      219.846d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15431.73 SOD {04:17:11.73} UT,   293.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.962
N_STARS:         190
X_OFFSET:        163 [pixels]
Y_OFFSET:        320 [pixels]
X_MAX:           1602 [pixels]
Y_MAX:           1759 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00442039000msufc0293.fits
SUN_POSTN:       293.34d {+19h 33m 22s}  -21.70d {-21d 42' 13"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.97d {+00h 59m 52s}  +11.88d {+11d 52' 57"}
MOON_DIST:        44.60 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 12 Jan 11 04:26:38 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.930d {+21h 59m 43s} (J2000)
POINT_DEC:       +26.485d {+26d 29' 05"} (J2000)
ROLL:            219.846d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15431.73 SOD {04:17:11.73} UT,   293.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     316498638
X_OFFSET:        722 [pixels]
Y_OFFSET:        879 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       1039
BINNING_INDEX:   1
IM_URL:          sw00442039000msuni0300.fits
SUN_POSTN:       293.34d {+19h 33m 22s}  -21.70d {-21d 42' 13"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.97d {+00h 59m 53s}  +11.89d {+11d 53' 08"}
MOON_DIST:        44.61 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 Circular #11553
M. Stamatikos (OSU/NASA/GSFC), A. P. Beardmore (U Leicester), J. R. Cummings (NASA/UMBC), J. M. Gelbord (PSU), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), O. M. Littlejohns (U Leicester), K. L. Page (U Leicester), J. L. Racusin (NASA/GSFC), T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU), E. Sonbas (GSFC/USRA/Adiyaman Univ.) and E. Troja (NASA/GSFC/ORAU) report on behalf of the Swift Team:
At 04:12:18 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110112 A (trigger=442039). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 329.941, +26.489 which is
```
   RA(J2000) = 21h 59m 46s
   Dec(J2000) = +26d 29' 20"
```
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 ~1700 counts/sec (15-350 keV), at the trigger time.
The XRT began observing the field at 04:13:33.9 UT, 75.5 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 329.9330, 26.4564 which is equivalent to:
```
   RA(J2000)  = 21h 59m 43.91s
   Dec(J2000) = +26d 27' 23.0"
```
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This location is 119 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 consistent with the Galactic value of 5.54 x 10^20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 80 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 none of the XRT error circle. The coverage of the XRT error circle by the 8'x8' region for the list of sources generated on-board is uncertain because the large number of sources filled the available telemetry. No correction has been made for the expected extinction corresponding to E(B-V) of 0.06.
Burst Advocate for this burst is M. Stamatikos (Michael.Stamatikos-1 AT 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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Jan 11 04:26:55 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     442039,   Seg_Num: 0
POINT_RA:        329.930d {+21h 59m 43s} (J2000)
POINT_DEC:       +26.485d {+26d 29' 05"} (J2000)
ROLL:            219.846d
IMG_START_DATE:  15573 TJD;    12 DOY;   11/01/12
IMG_START_TIME:  15431.73 SOD {04:17:11.73} UT,   293.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     316498638
X_OFFSET:        722 [pixels]
Y_OFFSET:        879 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       1039
BINNING_INDEX:   1
IM_URL:          sw00442039000msuni0300.fits
SUN_POSTN:       293.34d {+19h 33m 22s}  -21.70d {-21d 42' 13"}
SUN_DIST:         59.93 [deg]   Sun_angle= -2.4 [hr] (East of Sun)
MOON_POSTN:       14.98d {+00h 59m 54s}  +11.89d {+11d 53' 11"}
MOON_DIST:        44.61 [deg]
MOON_ILLUM:      47 [%]
GAL_COORDS:       81.71,-22.33 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      343.19, 35.98 [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 #11554
L.P. Xin, T. M. Zhang, Y.L. Qiu, J.Y. Wei, J. Wang, J.S. Deng, C. Wu, X. H. Han on behalf of EAFON report:
We began to observe GRB110112A (stamatikos et al., GCN 11553 ) with Xinglong TNT telescope at 10:08:35.375 (UT), 6 hours after the burst. 16 images in R-band were obtained with an exposure time of 300 sec for each frame.
After combining all these images, a new marginal source was found within the errorbox of X-ray counterpart ( stamatikos et al., GCN 11553).
Its coordinates ( RA and Dec ) are 21:59:43.8 26:27:25.9 (J2000) with an uncertainty of about 1 arcsecond.
The brightness of the source is estimated to be about 19.6 +/- 0.3 mag which is derived from USNO B1.0 R2 mag at the mean time of 6.5 hour after the burst.
Further observations and confirmation are encouraged.
This message may be cited.
For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org/grb/
GCN Circular #11556
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1127 s of XRT Photon Counting mode data and 2 UVOT images for GRB 110112A, 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 = 329.93240, +26.45636 which is equivalent to:
```
RA (J2000): 21h 59m 43.77s
Dec (J2000): +26d 27' 22.9"
```
with an uncertainty of 3.2 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, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #11557
S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU) (on behalf of the Swift-BAT team):
Using the data set from T-60 to T+123 sec from the recent telemetry downlink, we report further analysis of BAT short GRB 110112A (trigger #442039) (Stamatikos, et al., GCN Circ. 11553). The BAT ground-calculated position is RA, Dec = 329.936, 26.470 deg, which is
```
   RA(J2000)  =  21h 59m 44.6s 
   Dec(J2000) = +26d 28' 10.6" 
```
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 87%.
The mask-weighted light curve shows a single spike starting at ~T-0.1 sec and ending at ~T+0.5 sec. T90 (15-350 keV) is 0.5 +- 0.1 sec (estimated error including systematics).
The time-averaged spectrum from T-0.1 to T+0.5 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.14 +- 0.46. The fluence in the 15-150 keV band is 3.0 +- 0.9 x 10^-8 erg/cm2. The 1-sec peak photon flux measured from T-0.28 sec in the 15-150 keV band is 0.5 +- 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/442039/BA/
GCN Circular #11558
E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, V.Shumkov, S.Shurpakov Sternberg Astronomical Institute, Moscow State University
V.Krushinski, I.Zalozhnich, A. Popov Ural State University, Kourovka
K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres, S.Yazev, N.M.Budnev, Irkutsk State University
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB110112.18 48131 sec s after notice time and 48156 sec after GRB time at 2011-01-12 17:34:54.665 UT. On our first (180s exposure) set we haven`t found optical transient within SWIFT error-box (ra=21 59 45 dec=+26 29 24 r=0.050000). The 5-sigma upper limit has been about 18.3 mag (V) and 19.0 (R).
The message generated automaticaly. cited.
mailto: lipunov@sai.msu.ru
GCN Circular #11559
A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester), D. Baker (U. Leicester/U. Hertfordshire) report for a larger collaboration:
"We observed the field of the short GRB 110112A (Stamatikos et al. GCN 11553) with ACAM mounted on the William Herschel Telescope (WHT) on La Palma. Observations began 15.5 hours after the GRB. Within the XRT localization (Evan et al. GCN 11556) we detect a faint, possibly extended source at a position of
```
RA(J2000) 21:59:43.84 
DEC(J2000) 26:27:24.0
```
with an error of ~0.5" in each axis The source has a magnitude of i~22, calibrated against nearby stars from the USNO B1 catalog. This magnitude is fainter than that inferred for a candidate afterglow of Xin et al. (GCN 11554), suggestive of fading between the two epochs. We note that the positions of the two objects are only marginally consistent with each other, and suggest that the source observed in our WHT observations is a candidate host galaxy for GRB 110112A, although with a single epoch we cannot constrain any possible afterglow contribution at this time."
GCN Circular #11560
A. A. Breeveld (MSSL/UCL) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift/UVOT team:
Swift UVOT started observing the field of GRB 110112A with the white filter 85s after the trigger (Stamatikos et al., GCN Circ. 11553).
No optical afterglow consistent with the TNT or XRT positions (Xin et al., CGN Circ. 11554 and Evans et al., GCN Circ. 11556) is detected in individual or merged UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) are:
```
Filter      T_start   T_stop    Exp(s)      Mag (Upper limits)
---------------------------------------------------------------------------
white          85         235       147         >20.4
white      4499       6134        393        >21.3
v            4909        6544       393        >19.6
b            4294       5929        393        >20.3
u              287       5724        639        >20.2
uvw1     5319        5519       19.7        >18.8
uvm2     5079        6634       280         >18.9
uvw2     4705        6339        393        >19.2
----------------------------------------------------------------------------
```
The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.06 mag (Schlegel et al., 1998, ApJS, 500, 525).
GCN Circular #11561
A. P. Beardmore (U. Leicester) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift-XRT team:
We have analysed 23 ks of XRT data for GRB 110112A (Stamatikos et al. GCN Circ. 11553), from 82 s to 52.8 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 11556).
The light curve can be modelled with a power-law decay with a decay index of alpha=0.95 +/- 0.05.
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.3 (+0.4, -0.3). The best-fitting absorption column is 1.4 (+0.8, -0.7) x 10^21 cm^-2, in excess of the Galactic value of 5.5 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 3.4 x 10^-11 (5.4 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.4 (+0.8, -0.7) x 10^21 cm^-2
Galactic foreground: 5.5 x 10^20 cm^-2
Excess significance: 3.0 sigma
Photon index:	     2.3 (+0.4, -0.3)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00442039.
This circular is an official product of the Swift-XRT team.
GCN Circular #11566
H. Nakajima (Tokyo Tech), D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto), Y. Yatsu, T. Enomoto, K. Kawakami, K. Tokoyoda, T. Ohkawa and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 110112A (Stamatikos et al.,GCN 11553) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Akeno Observatory and Okayama Astrophysical Observatory.
We did not find any new point source within the enhanced XRT error circle (Evans et al., GCN 11556) in all the three bands. We could not detect the previously reported afterglow (Xin et al., GCN 11554).
Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration.
Akeno Observatory: The observation started on 2011-01-12 09:07:48 UT (~5 h after the trigger).
```
T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.21513    09:22:06    1200.0   >20.2  >20.0  >19.4
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
Okayama Astrophysical Observatory: The observation started on 2011-01-12 09:15:35 UT (~5.1 h after the trigger).
```
T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.23603    09:52:11    3840.0   >19.9  >19.8  >19.3
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #11589
K. Grankin, V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 110112A (Stamatikos et al., GCN 11553) with AZT-11 telescope of CrAO starting on Jan. 12 (UT) 16:35. In the enhanced Swift-XRT position (Evanset al., GCN 11556) we do not detect optical afterglow (Xin et al., GCN 11554) up to R=20.6. The photometry is based on the USNO B1.0 star 1164-0563915 (21 59 45.42 +26 27 18.3) assuming R=15.64.
```
T0+      Filter,   Exposure, mag.
(mid, d)              (s)

0.52955  R 13x180  R   >20.6
```
GCN Circular #11619
A. Zauderer, E. Berger, and W. Fong (Harvard) report:
We observed the position of the short GRB 110112A (GCN #11553) with the EVLA for 1 hour at 5 GHz starting on 2011 January 14.05 UT (1.87 days after the burst). No radio source is detected within the XRT error circle (GCN #11556) to a 3-sigma limit of 75 microJy.
We acknowledge the EVLA staff for their support of these observations.
1302.3221 from 15 Feb 13
Wen-fai Fong et al.: Demographics of the Galaxies Hosting Short-duration Gamma-Ray Bursts
We present observations of the afterglows and host galaxies of three short-duration gamma-ray bursts (GRBs): 100625A, 101219A and 110112A. We find that GRB 100625A occurred in a z=0.452 early-type galaxy with a stellar mass of 4.6e9 M_Sun and a stellar population age of 0.7 Gyr, and GRB 101219A originated in a star-forming galaxy at z=0.718 with a stellar mass of 1.4e9 M_Sun, a star formation rate of 16 M_Sun yr^-1, and a stellar population age of 50 Myr. We also report the discovery of the optical afterglow of GRB 110112A, which lacks a coincident host galaxy to i>26 mag and we cannot conclusively identify any field galaxy as a possible host. The bursts have inferred circumburst densities of ~1e-4-1 cm^-3, and isotropic-equivalent gamma-ray and kinetic energies of 1e50-1e51 erg. These events highlight the diversity of galaxies that host short GRBs. To quantify this diversity, we use the sample of 36 Swift short GRBs with robust associations to an environment (~1/2 of 68 short bursts detected by Swift to May 2012) and classify them as follows: late-type (50%), early-type (15%), inconclusive (20%), and host-less (lacking a coincident host galaxy to limits of >26 mag; 15%). To find likely ranges for the true late- and early-type fractions, we assign each of the host-less bursts to the late- or early-type category using probabilistic arguments, and consider the scenario that all hosts in the inconclusive category are early-type galaxies to set an upper bound on the early-type fraction. The most likely ranges for the late- and early-type fractions are ~60-80% and ~20-40%, respectively. We find no clear trend between gamma-ray duration and host type, and no change to the fractions when excluding events recently claimed as possible contaminants from the long GRB/collapsar population. Our reported demographics are consistent with a short GRB rate driven by both stellar mass and star formation.

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