Gamma-ray Burst 111215A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:10:00 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     509717,   Seg_Num: 0
GRB_RA:          349.548d {+23h 18m 12s} (J2000),
                 349.694d {+23h 18m 46s} (current),
                 348.941d {+23h 15m 46s} (1950)
GRB_DEC:         +32.475d {+32d 28' 32"} (J2000),
                 +32.541d {+32d 32' 27"} (current),
                 +32.202d {+32d 12' 07"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=3371 [image_cnts]
TRIGGER_DUR:     320.000 [sec]   (=5.3 [min])
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        15910 TJD;   349 DOY;   11/12/15
GRB_TIME:        50648.32 SOD {14:04:08.32} UT
GRB_PHI:         -26.43 [deg]
GRB_THETA:        42.30 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    8.16 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -2  +0  +0 +17  +0 
SUN_POSTN:       262.64d {+17h 30m 34s}  -23.26d {-23d 15' 52"}
SUN_DIST:         99.94 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      142.98d {+09h 31m 55s}   +9.44d {+09d 26' 08"}
MOON_DIST:       130.89 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.05,-26.40 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:        5.04, 33.61 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
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 = 60.87,-17.74 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:11:40 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     509717,   Seg_Num: 0
GRB_RA:          349.5578d {+23h 18m 13.87s} (J2000),
                 349.7033d {+23h 18m 48.79s} (current),
                 348.9502d {+23h 15m 48.04s} (1950)
GRB_DEC:         +32.4938d {+32d 29' 37.6"} (J2000),
                 +32.5593d {+32d 33' 33.3"} (current),
                 +32.2203d {+32d 13' 13.0"} (1950)
GRB_ERROR:       5.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.51e-09 [erg/cm2/sec]
GRB_SIGNIF:      7.34 [sigma]
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51066.02 SOD {14:11:06.02} UT,   417.7 [sec] since BAT Trigger Time
TAM[0-3]:        327.68 237.24 261.67 243.38
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       262.64d {+17h 30m 34s}  -23.26d {-23d 15' 52"}
SUN_DIST:         99.95 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      142.99d {+09h 31m 58s}   +9.43d {+09d 25' 48"}
MOON_DIST:       130.88 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.06,-26.39 [deg] galactic lon,lat of the burst
ECL_COORDS:        5.06, 33.62 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.20 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:12:02 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     509717,   Seg_Num: 0
GRB_RA:          349.5578d {+23h 18m 13.8s} (J2000),
                 349.7033d {+23h 18m 48.7s} (current),
                 348.9502d {+23h 15m 48.0s} (1950)
GRB_DEC:         +32.4938d {+32d 29' 37.6"} (J2000),
                 +32.5593d {+32d 33' 33.3"} (current),
                 +32.2203d {+32d 13' 13.0"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       54 [cnts]
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51066.02 SOD {14:11:06.02} UT,   417.7 [sec] since BAT Trigger Time
CENTROID_X:      290.79,  raw= 291  [pixels]
CENTROID_Y:      276.77,  raw= 277  [pixels]
ROLL:            248.61 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -50.02
GRB_POS_XRT_Z:   -30.43
IMAGE_URL:       sw00509717000msxps_rw.img
SUN_POSTN:       262.64d {+17h 30m 34s}  -23.26d {-23d 15' 53"}
SUN_DIST:         99.95 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.00d {+09h 31m 59s}   +9.43d {+09d 25' 44"}
MOON_DIST:       130.89 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.06,-26.39 [deg] galactic lon,lat of the burst
ECL_COORDS:        5.06, 33.62 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:11:52 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     509717,   Seg_Num: 0
GRB_RA:          349.5578d {+23h 18m 13.8s} (J2000),
                 349.7033d {+23h 18m 48.7s} (current),
                 348.9502d {+23h 15m 48.0s} (1950)
GRB_DEC:         +32.4938d {+32d 29' 37.6"} (J2000),
                 +32.5593d {+32d 33' 33.3"} (current),
                 +32.2203d {+32d 13' 13.0"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       54 [cnts]
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51066.02 SOD {14:11:06.02} UT,   417.7 [sec] since BAT Trigger Time
CENTROID_X:      290.79,  raw= 291  [pixels]
CENTROID_Y:      276.77,  raw= 277  [pixels]
ROLL:            248.61 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -50.02
GRB_POS_XRT_Z:   -30.43
IMAGE_URL:       sw00509717000msxps_rw.img
SUN_POSTN:       262.64d {+17h 30m 34s}  -23.26d {-23d 15' 52"}
SUN_DIST:         99.95 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      142.99d {+09h 31m 59s}   +9.43d {+09d 25' 46"}
MOON_DIST:       130.89 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.06,-26.39 [deg] galactic lon,lat of the burst
ECL_COORDS:        5.06, 33.62 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:12:41 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     509717,   Seg_Num: 0
GRB_RA:          349.548d {+23h 18m 12s} (J2000),
                 349.694d {+23h 18m 46s} (current),
                 348.941d {+23h 15m 46s} (1950)
GRB_DEC:         +32.475d {+32d 28' 32"} (J2000),
                 +32.541d {+32d 32' 27"} (current),
                 +32.202d {+32d 12' 07"} (1950)
GRB_DATE:        15910 TJD;   349 DOY;   11/12/15
GRB_TIME:        50648.32 SOD {14:04:08.32} UT
TRIGGER_INDEX:   20000
GRB_PHI:         -26.43 [deg]
GRB_THETA:        42.30 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     320.000 [sec]   (=5.3 [min])
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    8.16 [sigma]
LC_URL:          sw00509717000msb.lc
SUN_POSTN:       262.64d {+17h 30m 35s}  -23.26d {-23d 15' 53"}
SUN_DIST:         99.94 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.00d {+09h 32m 00s}   +9.43d {+09d 25' 36"}
MOON_DIST:       130.91 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.05,-26.40 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:        5.04, 33.61 [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 an image 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 = 60.87,-17.74 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:14:29 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.572d {+23h 18m 17s} (J2000)
POINT_DEC:       +32.484d {+32d 29' 03"} (J2000)
POINT_ROLL:      248.613d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51074.32 SOD {14:11:14.32} UT,   426.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.015
N_STARS:         65
X_OFFSET:        624 [pixels]
Y_OFFSET:        480 [pixels]
X_MAX:           1583 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00509717000msufc0426.fits
SUN_POSTN:       262.65d {+17h 30m 35s}  -23.26d {-23d 15' 53"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.02d {+09h 32m 04s}   +9.42d {+09d 25' 15"}
MOON_DIST:       130.91 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.40 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:14:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.572d {+23h 18m 17s} (J2000)
POINT_DEC:       +32.484d {+32d 29' 03"} (J2000)
POINT_ROLL:      248.613d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51074.32 SOD {14:11:14.32} UT,   426.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.015
N_STARS:         65
X_OFFSET:        624 [pixels]
Y_OFFSET:        480 [pixels]
X_MAX:           1583 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00509717000msufc0426.fits
SUN_POSTN:       262.65d {+17h 30m 35s}  -23.26d {-23d 15' 53"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.02d {+09h 32m 05s}   +9.42d {+09d 25' 12"}
MOON_DIST:       130.91 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.40 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.61 [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:     Thu 15 Dec 11 14:15:42 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.572d {+23h 18m 17s} (J2000)
POINT_DEC:       +32.484d {+32d 29' 03"} (J2000)
ROLL:            248.613d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51074.32 SOD {14:11:14.32} UT,   426.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     345651082
X_OFFSET:        909 [pixels]
Y_OFFSET:        938 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1069
Y_GRB_POS:       1098
BINNING_INDEX:   1
IM_URL:          sw00509717000msuni0434.fits
SUN_POSTN:       262.65d {+17h 30m 35s}  -23.26d {-23d 15' 53"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.03d {+09h 32m 07s}   +9.42d {+09d 25' 01"}
MOON_DIST:       130.91 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.40 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.61 [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:     Thu 15 Dec 11 14:15:57 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.572d {+23h 18m 17s} (J2000)
POINT_DEC:       +32.484d {+32d 29' 03"} (J2000)
ROLL:            248.613d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51074.32 SOD {14:11:14.32} UT,   426.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     345651082
X_OFFSET:        909 [pixels]
Y_OFFSET:        938 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1069
Y_GRB_POS:       1098
BINNING_INDEX:   1
IM_URL:          sw00509717000msuni0434.fits
SUN_POSTN:       262.65d {+17h 30m 35s}  -23.27d {-23d 15' 53"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.03d {+09h 32m 07s}   +9.42d {+09d 24' 58"}
MOON_DIST:       130.92 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.40 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #12681
S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL), V. Mangano (INAF-IASFPA), F. E. Marshall (NASA/GSFC), C. J. Mountford (U Leicester), P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester), C. Pagani (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), M. H. Siegel (PSU), R. L. C. Starling (U Leicester), T. N. Ukwatta (MSU) and B.-B. Zhang (PSU) report on behalf of the Swift Team:
At 14:04:08 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111215A (trigger=509717). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 349.548, +32.475 which is
```
   RA(J2000) = 23h 18m 12s
   Dec(J2000) = +32d 28' 32"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual for an image trigger, the BAT light curve shows nothing of note.
The XRT began observing the field at 14:11:06.0 UT, 417.7 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 349.5578, 32.4938 which is equivalent to:
```
   RA(J2000)  = +23h 18m 13.87s
   Dec(J2000) = +32d 29' 37.7"
```
with an uncertainty of 5.3 arcseconds (radius, 90% containment). This location is 73 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 1.51e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 426 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 0.06.
Burst Advocate for this burst is S. R. Oates (sro AT mssl.ucl.ac.uk). 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:     Thu 15 Dec 11 14:21:20 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.575d {+23h 18m 18s} (J2000)
POINT_DEC:       +32.483d {+32d 28' 59"} (J2000)
POINT_ROLL:      248.614d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51504.72 SOD {14:18:24.72} UT,   856.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.105
N_STARS:         190
X_OFFSET:        349 [pixels]
Y_OFFSET:        378 [pixels]
X_MAX:           1788 [pixels]
Y_MAX:           1817 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00509717000msufc0856.fits
SUN_POSTN:       262.65d {+17h 30m 36s}  -23.27d {-23d 15' 54"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.08d {+09h 32m 19s}   +9.40d {+09d 23' 55"}
MOON_DIST:       130.95 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.41 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.60 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 Dec 11 14:21:36 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.575d {+23h 18m 18s} (J2000)
POINT_DEC:       +32.483d {+32d 28' 59"} (J2000)
POINT_ROLL:      248.614d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51504.72 SOD {14:18:24.72} UT,   856.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.105
N_STARS:         190
X_OFFSET:        349 [pixels]
Y_OFFSET:        378 [pixels]
X_MAX:           1788 [pixels]
Y_MAX:           1817 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00509717000msufc0856.fits
SUN_POSTN:       262.65d {+17h 30m 36s}  -23.27d {-23d 15' 54"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.08d {+09h 32m 19s}   +9.40d {+09d 23' 51"}
MOON_DIST:       130.96 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.41 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.60 [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:     Thu 15 Dec 11 14:22:49 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.575d {+23h 18m 18s} (J2000)
POINT_DEC:       +32.483d {+32d 28' 59"} (J2000)
ROLL:            248.614d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51504.72 SOD {14:18:24.72} UT,   856.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     345651512
X_OFFSET:        908 [pixels]
Y_OFFSET:        937 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1068
Y_GRB_POS:       1097
BINNING_INDEX:   1
IM_URL:          sw00509717000msuni0864.fits
SUN_POSTN:       262.65d {+17h 30m 36s}  -23.27d {-23d 15' 54"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.09d {+09h 32m 22s}   +9.39d {+09d 23' 37"}
MOON_DIST:       130.97 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.41 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.60 [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:     Thu 15 Dec 11 14:23:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     509717,   Seg_Num: 0
POINT_RA:        349.575d {+23h 18m 18s} (J2000)
POINT_DEC:       +32.483d {+32d 28' 59"} (J2000)
ROLL:            248.614d
IMG_START_DATE:  15910 TJD;   349 DOY;   11/12/15
IMG_START_TIME:  51504.72 SOD {14:18:24.72} UT,   856.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     345651512
X_OFFSET:        908 [pixels]
Y_OFFSET:        937 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1068
Y_GRB_POS:       1097
BINNING_INDEX:   1
IM_URL:          sw00509717000msuni0864.fits
SUN_POSTN:       262.65d {+17h 30m 36s}  -23.27d {-23d 15' 54"}
SUN_DIST:         99.96 [deg]   Sun_angle= -5.8 [hr] (East of Sun)
MOON_POSTN:      143.09d {+09h 32m 22s}   +9.39d {+09d 23' 34"}
MOON_DIST:       130.97 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      101.07,-26.41 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        5.07, 33.60 [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 #12682
L.P. Xin, J.Y. Wei, Y. L. Qiu, J. Wang, J.S. Deng, C. Wu, X. H. Han on behalf of EAFON report:
We began to observe GRB 111215A ( Oates et al., GCN 12681) with Xinglong TNT telescope at 14:20:23 (UT), about 16.25 min after the burst. 30 R-band images were obtained. The exposure time is 60 sec for each frame.
No new source was detected in the combined R band image within the errorbox of XRT position. The upper limit was estimated to be about 18.0 mag derived from USNO B1.0 R2 mag, at the mean time of 32.75 min after the burst.
This message may be cited.
For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org:8080/grb/index.html"
GCN Circular #12683
D. Xu (WIS/NAOC), X.-H. Zhao (YNAO), J.-R. Mao (KASI/YNAO), J.-M. Bai (YNAO) report:
We observed the field of GRB 111215A (Oates et al., GCN 12681) at the 2.4m Gao-Mei-Gu (GMG) telescope equipped with YFOSC. Observations started at 14:26:44 UT (i.e., 22.6 mins after the burst) and a series of R-band images (totally 1700s exposure) were obtained in a seeing of ~2.8".
No optical source was detected within the XRT error circle (ref., GCN 12681) to a 3sigma limit of R~22.8 mag, calibrated with nearby USNO B1 stars.
The image trigger mode of this burst and the above R-band upper limit might indicate high-redshift. NIR follow-ups are encouraged.
GCN Circular #12685
R. Usui, Y. Aoki, S. Song, M. Hayashi, K. Kawakami, K. Tokoyoda, Y. Saito, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed GRB 111215A (S. R. Oates et al, GCN12681) with the optical three color (g, Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.
We started the observation 387 sec after the BAT trigger from 2011-12-15 14:10:35 UT. And we did not find any new point source within the XRT error circle (S. R. Oates et al, GCN12681) in the three bands. The results of photometry (3sigma upper limits) are listed below.
#The photon flux were calibrated against GSC2.3 catalog.
```
T0+[sec]      MID-UT     T-EXP[sec]       g'              Rc           Ic
----------------------------------------------------------------------------------------
    387         14:33:55        2700          > 19.3      > 19.4      > 19.0
----------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [sec]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12686
S. B. Pandey, Rupak Roy, Brajesh Kumar and R. K. S. Yadav (ARIES, NainiTal, India, on behalf of larger Indian GRB collaboration).
GRB 111215A field, localized by Swift (Oates et al., GCN 12681), was observed with 1.04m telescope at ARIES NainiTal starting 14:22:30 UT (~18 minutes after the burst) in R_c pass-band with an exposure time of 300 sec each.
Photometry of the co-added R_c frame (300 sec x 6) in comparison to nearby USNO stars did not detect any new source within the XRT error-box down to a limiting magnitude of ~ 21.5 mag.
This message may be cited.
GCN Circular #12687
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich, S. Shurpakov Sternberg Astronomical Institute, Moscow State University
K.Ivanov, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev,E.Konstantinov, Irkutsk State University
E. Sinykov, V.Yurkov, Yu.Sergienko, D.Varda, Blagoveschensk Educational State University, Blagoveschensk
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka
3 Robotic telescopes MASTER II was pointing to the GRB111215A (Oates et al., GCN CIRCULAR NUMBER: 12681). Two very wide field cameras was observed Swift error box before, during and after GRB trigger time.
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka(Siberia) was pointed to the GRB111215A 26 sec s after notice time and 381 sec after GRB time at 2011-12-15 14:10:29.44 UT in two polarizarions. On our first (80s exposure) set we haven`t found optical transient within SWIFT error-box (ra=23 18 12 dec=+32 28 47 r=0.050000). The 5-sigma upper limit has been about 18.8 mag
MASTER II robotic telescope located in MASTER-Amur was pointed to the GRB111215A 214 sec s after notice time and 567 sec after GRB time at 2011-12-15 14:13:35.289 UT in two diagonal polarizarions. On our first (110s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 17.5 mag
MASTER II robotic telescope located near Kislovodsk was pointed to the GRB111215A 7655 sec s after notice time and 8007 sec after GRB time at 2011-12-15 16:17:35.91 UT (time delay is so long due to weather conditions). On our first (180s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 18.1 mag
Two MASTER Very Wide Field Cameras located at Tunka (D=68 mm, 420 square degrees, 11 Mpx) was observed GRB error box with 5 s exposure befoure, during and after GRB Trigger Time without time gap between images.
Our unfiltered images are calibrated relative to Tycho stars (V). The magnitude limit of the each emage is 12.0 m at the edge of FOW.
We do not detect OT. The video from MASTER VWF cameras is available at http://master.sai.msu.ru/static/GRB111215/grb111215.html
The reduction is continuated.
The message may be cited.
GCN Circular #12688
F. Aceituno (OSN,IAA-CSIC), A.J. Castro-Tirado, A. de Ugarte Postigo, J.C. Tello, J. Gorosabel (IAA-CSIC), report on behalf of a larger collaboration:
"We have observed the field of GRB 111215A (Oates et al., GCN 12681) with the 1.5m telescope at Observatorio de Sierra Nevada (OSN), Granada, Spain. The data were acquired in the I-band on Dec 15.7537 -- Dec. 15.8168 UT (starting ~4 hour post burst), with a total exposure time of 18x300s. A preliminary analysis reveals no object brighter than I=21.7 in the XRT error circle. The calibration was carried out using the USNO B1.0 catalogue."
GCN Circular #12689
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 111215A (trigger #509717) (Oates, et al., GCN Circ. 12681). The BAT ground-calculated position is RA, Dec = 349.582, 32.440 deg, which is
```
   RA(J2000)  =  23h 18m 19.6s 
   Dec(J2000) = +32d 26' 24.2" 
```
with an uncertainty of 4.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 46%.
The mask-weighted light curve shows the emission starting at ~T-110 sec, although we note that the burst location came into the BAT FoV around T-200 sec, so we can not make any statement about possible earlier emission. There are a few overlapping peaks at ~T+20 sec, ~T+170 sec, and T+300 sec, the the lightcurve slowly decreases back to baseline around T+1500 sec. T90 (15-350 keV) is 796 +- 250 sec (estimated error including systematics).
The time-averaged spectrum from T-116.4 to T+960.1 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.70 +- 0.18. The fluence in the 15-150 keV band is 4.5 +- 0.5 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+216.35 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 duration of this burst is very long, and we note that this location is well off the Galactic Plane (lon=101,lat=-26). We can not rule out a non-GRB source for this event.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/509717/BA/
GCN Circular #12690
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 2785 s of XRT Photon Counting mode data and 4 UVOT images for GRB 111215A, 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 = 349.55538, +32.49401 which is equivalent to:
```
RA (J2000): 23h 18m 13.29s
Dec (J2000): +32d 29' 38.4"
```
with an uncertainty of 1.4 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 #12691
N. Kawai, M. Morii (Tokyo Tech), H. Negoro (Nihon U.), M. Serino (RIKEN), K. Sugimori, R. Usui, T. Toizumi, Y. Aoki, S. Song (Tokyo Tech), S. Ueno, H. Tomida, M. Kohama, M. Ishikawa (JAXA), T. Mihara, M. Sugizaki, S. Nakahira, T. Yamamoto, T. Sootome, M. Matsuoka (RIKEN), A. Yoshida, K. Yamaoka (AGU), H. Tsunemi, M. Kimura, H. Kitayama (Osaka U.), M. Nakajima, F. Suwa, M. Asada, H. Sakakibara (Nihon U.), Y. Ueda, K. Hiroi, M. Shidatsu (Kyoto U.), Y. Tsuboi, T. Matsumura, K. Yamazaki (Chuo U.) M. Yamauchi, Y. Nishimura, T. Hanayama (Miyazaki U.) report on behalf of the MAXI team:
MAXI/GSC observed the position of GRB 111215A (swift trigger=509717, Oates et al. GCN #12681) at 13:12 and 14:44 on December 5, 2011 (UT), 52 min before and 40 min after the trigger time.
The source was marginally detected as follows:
```
Time    2-4 keV          4-10 keV
13:12   4 +-  7 mCrab  52 +- 19 mCrab
14:44  16 +- 10 mCrab  41 +- 19 mCrab
```
(uncertainties are 1-sigma statistical errors)
If this detections are true it implies that the emission of GRB 111215A lasted for more than 1.5 hours. Together with the long trigger timescale (320 s) by Swift BAT, unusual for a GRB, we suggest that it may be a non-GRB X-ray transient, such as an X-ray binary, AGN, or extragalactic TDE.
Multiwavelength follow-up observations are strongly encouraged.
GCN Circular #12692
A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), O.M. Littlejohns (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU) and S.R. Oates report on behalf of the Swift-XRT team:
We have analysed 7.1 ks of XRT data for GRB 111215A (Oates et al. GCN Circ. 12681), from 407 s to 59.3 ks after the BAT trigger. The data comprise 2.2 ks in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN. Circ 12690).
The late-time light curve (from T0+5.9 ks) can be modelled with an initial power-law decay with an index of alpha=2.13 (+0.13, -0.12), followed by a break at T+14.6 ks to an alpha of 1.21 (+0.15, -0.16).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.847 (+/-0.027). The best-fitting absorption column is 4.10 (+/-0.12) x 10^21 cm^-2, in excess of the Galactic value of 5.6 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.14 (+/-0.12) and a best-fitting absorption column of 3.2 (+0.5, -0.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.9 x 10^-11 (6.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     3.2 (+0.5, -0.4) x 10^21 cm^-2
Galactic foreground: 5.6 x 10^20 cm^-2
Excess significance: 10.2 sigma
Photon index:	     2.14 (+/-0.12)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00509717.
This circular is an official product of the Swift-XRT team.
GCN Circular #12693
S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111215A 426 s after the BAT trigger (Oates et al., GCN Circ. 12681). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 12690) 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           426          576          147         >21.7
white              426        19036          645         >22.0
v                  732        13257          608         >20.1
b                  657        18972         1198         >21.6
u                  632         6983          313         >20.7
w1                 608        22616          593         >20.6
m2                 583         6572          313         >20.7
w2                 708        12928         1260         >21.3
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.06 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12694
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 111215A (Oates et al., GCNC 12681) 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 2011-12-15 14:10:37 UT (~6.5 min after the burst). We did not find any new point source within the enhanced XRT circle (Beardmore et al., GCNC 12690) in all the three bands.
Photometric results and are listed below. We used GSC2.3 catalog for flux calibration.
```
T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.03242    14:50:49    3420.0    >18.6  >19.0  >18.7
--------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12695
P. D'Avanzo, A. Melandri, S. Covino (INAF/OABr), L. A. Antonelli, V. D'Elia (INAF/OAR and ASDC/ASI), E. Palazzi (INAF/IASF Bo), D. Fugazza (INAF/OABr), G. Tagliaferri (INAF/OABr), and S. D. Vergani (INAF/OABr), report on behalf of the CIBO collaboration:
We observed the field of GRB 111215A (Oates et al., GCN 12681) with the TNG telescope located in the Canary Islands. We secured 30 min Ks-band imaging with the NICS instrument, with a mean time Dec 15.845 UT (6.30 hr after the GRB trigger).
Within the UVOT-enhanced XRT error circle (Beardmore et al., GCN 12690), we detect no new source down to a limiting magnitude K > 19 (Vega, calibrated against the 2MASS catalog).
Taking the X-ray flux at the time of the TNG observation from the UK X-ray light curve repository (http://www.swift.ac.uk/xrt_curves/00509717/), we compute a broad-band optical-to-X-ray spectral index beta_OX < 0.25, which classifies GRB 111215A as dark according to the widely adopted definition of Jakobsson et al. (2004, ApJ, 617, 21). The non detection in the K band, coupled with the significant absorption in the X-ray spectrum (Beardmore et al., GCN 12692), suggests a highly extinguished, rather than a high redshift, event. Deep observations to look for a host galaxy are encouraged.
We acknowledge excellent support from the observing staff at the TNG, especially Marco Pedani and Giovanni Mainella.
GCN Circular #12696
N. R. Tanvir, K. Wiersema (U. Leicester), A. Melandri (INAF-OAB), T. Kruehler, J. Fynbo (DARK), A. J. Levan (U. Warwick), C. G. Mundell, R. J. Smith (LJMU), C. Guidorzi (U. Ferrara), D. Xu (WIS) and I. Skillen (ING) report:
We imaged the field of GRB111215A (Oates et al. GCN12681) using the WHT, the LT and the NOT, all on La Palma, on the night of 2011-Dec-15 (UT). Seeing conditions were rather poor (FWHM~2"), and no counterpart was located to the following 3-sigma limits at the given mid-times post-burst:
```
WHT/LIRIS (calibrated against 2MASS)
K>19.3 at 4hr 55m
J>19.4 at 5hr 15m

LT/RATCam (calibrated against SDSS)
z'>21.7 at 6hr 50m

NOT/StanCam (calibrated against SDSS)
z'>22.5 at 6hr 50m
```
The K-band limit is consistent with that provided by D'Avanzo et al. (GCN12695) from the TNG, and confirms this source to be dark even in the infrared.
We are grateful to Ilia Ilyin for assistance in obtaining the NOT observations.
GCN Circular #12697
S. B. Cenko (UC Berkeley), P. E. Nugent (LBNL / UC Berkeley), and S. R. Kulkarni (Caltech) report on behalf of a larger collaboration:
We have examined pre-outburst imaging of the location of GRB111215A (Oates et al., GCN12681) obtained over the last 7 years with the Palomar 48 inch Oschin Schmidt telescope.
As part of the Palomar Transient Factory, we have imaged the location of GRB111215A regularly (every ~ 3-4 nights) over the time period from June - October 2011. Coadding all images of this location, no sources are detected within the XRT error circle (Beardmore et al., GCN12690) to a limiting magnitude of r' > 22.8 mag (calibrated with respect to several nearby field stars from SDSS). Furthermore, no previous outbursts are detected in any individual frames over this period, to a typical limiting magnitude of r' > 20.5 mag.
In addition, we co-added 117 archival images from the DeepSky* project at Palomar Observatory obtained over the time period from 2004-2008 as part of the Palomar-Quest Consortium. No source is detected at the XRT position to a limiting magnitude of i' > 22.6 mag.
* http://supernova.lbl.gov/~nugent/deepsky.html
GCN Circular #12703
V. Rumyantsev, N. Pit' (CrAO), A. Volnova (SAI MSU), M. Andreev (Terskol Branch of INASAN), N. Parakhin, (IC AMER, NASU), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of GRB 111215A (Oates et al. GCN 12681) with AZT-11 telescope of CrAO observatory starting on Dec.15 (UT) 15:18:22 under mean seeing (FWHM) of 3.1 arsces and with Zeiss-600 telescope of Mt.Terskol observatory starting on Dec.15 (UT) 21:03:45 under mean seeing (FWHM) of 1.8 arsces . We took several frames in R-band. Within enhanced Swift-XRT position (Beardmore et al. GCN 12690) we do not detected any optical source. A photometry is based on the nearby USNO-B1.0 stars (R2):
```
T_start UT  T0+        Filter, Exposure, OT,  uplim (3 sigma)
                  (mid, d)            (s)

15:18:22  0.0738       R     21x180    n/d     21.0
21:03:45  0.3113       R     51x60      n/d     19.3 
```
GCN Circular #12710
Authors: A. Horesh (Caltech), J. Carpenter (Caltech), A. Corsi (Caltech), A. Zauderer (CfA), S. R. Kulkarni (Caltech), E. Berger (CfA), D. A. Frail (NRAO), S. B. Cenko (UC Berkeley), D. Perley (Caltech)
On 2011 December 17.04 UT (1.46 days after burst) we observed GRB111215A (Oates et al., GCN12681) with CARMA at 93 GHz. We detected the source at RA=23:18:13.32, Dec=+32:29:39.09 (J2000). This position is consistent with the Swift-XRT position.
We continue to monitor the source with CARMA.
GCN Circular #12711
A. Zauderer and E. Berger (Harvard) report on behalf of a larger collaboration:
"We observed the position of GRB 111215A (GCN 12681) with the EVLA at 21.8 GHz beginning on 2011 Dec 18.93 UT (3.35 days after the burst). We report a radio counterpart consistent with the Swift-XRT position (GCN 12690, http://www.swift.ac.uk/xrt_positions) and the reported CARMA detection by Horesh et al. (GCN 12710).
The position of the detected EVLA radio source is (J2000):
```
RA  =   23:18:13.310 +/- 0.001
Dec =  +32:29:39.18 +/- 0.01
```
Follow-up observations are ongoing."
GCN Circular #12734
S. B. Cenko, J. S. Bloom, J. M. Silverman, A. N. Morgan (UC Berkeley), D. A. Perley (Caltech), A. Cucchiara, J. X. Prochaska (UCSC / UCO Lick), A. V. Filippenko (UC Berkeley), and P. E. Nugent (LBNL / UC Berkeley) report on behalf of a larger collaboration:
We have imaged the field of GRB111215A (Oates et al., GCN 12681) with the Low-Resolution Imaging Spectrometer (LRIS) mounted on the 10 m Keck I telescope beginning at 5:12 UT on 2012 Dec 26 (~ 10.6 days after the Swift BAT trigger). Near the position of the radio and mm counterpart (Horesh et al., GCN 12710; Zauderer et al., GCN 12711), we detect a faint source with coordinates:
RA: 23:18:13.29 Dec: +32:29:38.8 (J2000.0)
Astrometric calibration was performed with respect to several 2MASS point sources in the field of view, and we estimate an uncertainty of ~ 200 mas in each coordinate. We measure a magnitude for this object of R ~ 25.2 (referenced to nearby point sources from the Sloan Digital Sky Survey).
Using the sky density of objects of this brightness (Hogg et al., 1997, MNRAS, 288, 404), we estimate the probability of chance alignment (e.g., Bloom et al., 2002, AJ, 123, 1111) to be relatively small (<~ 1%). We therefore consider it likely that this object is associated with GRB111215A.
A second, fainter source is visible ~ 1.5" NE of the radio position. The relation of this source to GRB111215A is not clear at the moment, as the probability of chance coincidence at this radius and brightness is not negligible.
GCN Report 358.1
GCN_Report 358.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_358_1.pdf by S.R. Oates at MSSL-UCL titled: "Final Swift Observations of GRB 111215A"
1408.3923 from 19 Aug 14
A.J. van der Horst et al.: Detailed Afterglow Modeling and Host Galaxy Properties of the Dark GRB 111215A
Gamma-ray burst (GRB) 111215A was bright at X-ray and radio frequencies, but not detected in the optical or near-infrared (nIR) down to deep limits. We have observed the GRB afterglow with the Westerbork Synthesis Radio Telescope and Arcminute Microkelvin Imager at radio frequencies, with the William Herschel Telescope and Nordic Optical Telescope in the nIR/optical, and with the Chandra X-ray Observatory. We have combined our data with the Swift X-Ray Telescope monitoring, and radio and millimeter observations from the literature to perform broadband modeling, and determined the macro- and microphysical parameters of the GRB blast wave. By combining the broadband modeling results with our nIR upper limits we have put constraints on the extinction in the host galaxy. This is consistent with the optical extinction we have derived from the excess X-ray absorption, and higher than in other dark bursts for which similar modeling work has been performed. We also present deep imaging of the host galaxy with the Keck I telescope, Spitzer Space Telescope, and Hubble Space Telescope (HST), which resulted in a well-constrained photometric redshift, giving credence to the tentative spectroscopic redshift we obtained with the Keck II telescope, and estimates for the stellar mass and star formation rate of the host. Finally, our high resolution HST images of the host galaxy show that the GRB afterglow position is offset from the brightest regions of the host galaxy, in contrast to studies of optically bright GRBs.

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