Gamma-ray Burst 111225A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 03:51:22 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.102d {+00h 52m 24s} (J2000),
                  13.274d {+00h 53m 06s} (current),
                  12.384d {+00h 49m 32s} (1950)
GRB_DEC:         +51.589d {+51d 35' 19"} (J2000),
                 +51.654d {+51d 39' 13"} (current),
                 +51.317d {+51d 19' 02"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       13734 [cnts]    Image_Peak=338 [image_cnts]
TRIGGER_DUR:     4.096 [sec] 
TRIGGER_INDEX:   298     E_range: 25-100 keV
BKG_INTEN:       115829 [cnts]
BKG_TIME:        13784.28 SOD {03:49:44.28} UT
BKG_DUR:         40 [sec]
GRB_DATE:        15920 TJD;   359 DOY;   11/12/25
GRB_TIME:        13837.79 SOD {03:50:37.79} UT
GRB_PHI:         -137.45 [deg]
GRB_THETA:        17.56 [deg]
SOLN_STATUS:     0x2003
RATE_SIGNIF:     10.39 [sigma]
IMAGE_SIGNIF:    7.52 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  -2  +0  +0 +40  +0 
SUN_POSTN:       273.25d {+18h 13m 01s}  -23.40d {-23d 24' 12"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      278.97d {+18h 35m 53s}  -20.98d {-20d 58' 38"}
MOON_DIST:       108.92 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       36.08, 41.52 [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:        There is a bright star (mag=6.21) 7.95 arcmin from this position.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 253.01,16.93 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 03:52:38 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.1548d {+00h 52m 37.15s} (J2000),
                  13.3276d {+00h 53m 18.61s} (current),
                  12.4369d {+00h 49m 44.86s} (1950)
GRB_DEC:         +51.5741d {+51d 34' 26.7"} (J2000),
                 +51.6390d {+51d 38' 20.4"} (current),
                 +51.3026d {+51d 18' 09.3"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.96e-09 [erg/cm2/sec]
GRB_SIGNIF:      9.89 [sigma]
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13925.94 SOD {03:52:05.94} UT,   88.1 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.23 261.56 243.67
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       273.25d {+18h 13m 01s}  -23.40d {-23d 24' 12"}
SUN_DIST:        114.27 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      278.98d {+18h 35m 56s}  -20.98d {-20d 58' 32"}
MOON_DIST:       108.94 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.12,-11.30 [deg] galactic lon,lat of the burst
ECL_COORDS:       36.10, 41.49 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.16 arcmin from the BAT position.  
COMMENTS:        There is a bright star (mag=6.21) 9.86 arcmin from the XRT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 03:52:49 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.1548d {+00h 52m 37.1s} (J2000),
                  13.3276d {+00h 53m 18.6s} (current),
                  12.4369d {+00h 49m 44.8s} (1950)
GRB_DEC:         +51.5741d {+51d 34' 26.7"} (J2000),
                 +51.6390d {+51d 38' 20.4"} (current),
                 +51.3026d {+51d 18' 09.3"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       98 [cnts]
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13925.94 SOD {03:52:05.94} UT,   88.1 [sec] since BAT Trigger Time
CENTROID_X:      341.98,  raw= 342  [pixels]
CENTROID_Y:      326.83,  raw= 327  [pixels]
ROLL:            262.18 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   67.96
GRB_POS_XRT_Z:   90.24
IMAGE_URL:       sw00510341000msxps_rw.img
SUN_POSTN:       273.25d {+18h 13m 01s}  -23.40d {-23d 24' 12"}
SUN_DIST:        114.27 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      278.98d {+18h 35m 56s}  -20.98d {-20d 58' 31"}
MOON_DIST:       108.94 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.12,-11.30 [deg] galactic lon,lat of the burst
ECL_COORDS:       36.10, 41.49 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 03:52:57 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.1548d {+00h 52m 37.1s} (J2000),
                  13.3276d {+00h 53m 18.6s} (current),
                  12.4369d {+00h 49m 44.8s} (1950)
GRB_DEC:         +51.5741d {+51d 34' 26.7"} (J2000),
                 +51.6390d {+51d 38' 20.4"} (current),
                 +51.3026d {+51d 18' 09.3"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       98 [cnts]
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13925.94 SOD {03:52:05.94} UT,   88.1 [sec] since BAT Trigger Time
CENTROID_X:      341.98,  raw= 342  [pixels]
CENTROID_Y:      326.83,  raw= 327  [pixels]
ROLL:            262.18 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   67.96
GRB_POS_XRT_Z:   90.24
IMAGE_URL:       sw00510341000msxps_rw.img
SUN_POSTN:       273.25d {+18h 13m 01s}  -23.40d {-23d 24' 12"}
SUN_DIST:        114.27 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      278.99d {+18h 35m 57s}  -20.98d {-20d 58' 30"}
MOON_DIST:       108.94 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.12,-11.30 [deg] galactic lon,lat of the burst
ECL_COORDS:       36.10, 41.49 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 03:56:24 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.102d {+00h 52m 24s} (J2000),
                  13.274d {+00h 53m 06s} (current),
                  12.384d {+00h 49m 32s} (1950)
GRB_DEC:         +51.589d {+51d 35' 19"} (J2000),
                 +51.654d {+51d 39' 13"} (current),
                 +51.317d {+51d 19' 02"} (1950)
GRB_DATE:        15920 TJD;   359 DOY;   11/12/25
GRB_TIME:        13837.79 SOD {03:50:37.79} UT
TRIGGER_INDEX:   298
GRB_PHI:         -137.45 [deg]
GRB_THETA:        17.56 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     4.096 [sec] 
SOLN_STATUS:     0x2003
RATE_SIGNIF:     10.39 [sigma]
IMAGE_SIGNIF:    7.52 [sigma]
LC_URL:          sw00510341000msb.lc
SUN_POSTN:       273.26d {+18h 13m 02s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.02d {+18h 36m 05s}  -20.97d {-20d 58' 12"}
MOON_DIST:       108.88 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       36.08, 41.52 [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:        There is a bright star (mag=6.21) 7.95 arcmin from this position.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 253.01,16.93 [deg].  
COMMENTS:        The 3rd packet (of 3) was missing in the lightcurve data stream.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:07:13 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.110d {+00h 52m 26s} (J2000)
POINT_DEC:       +51.589d {+51d 35' 19"} (J2000)
POINT_ROLL:      262.182d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13932.87 SOD {03:52:12.87} UT,   95.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.834
N_STARS:         190
X_OFFSET:        272 [pixels]
Y_OFFSET:        280 [pixels]
X_MAX:           1711 [pixels]
Y_MAX:           1719 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00510341000msufc0095.fits
SUN_POSTN:       273.27d {+18h 13m 04s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.14d {+18h 36m 32s}  -20.96d {-20d 57' 17"}
MOON_DIST:       108.81 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.08, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:07:36 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.110d {+00h 52m 26s} (J2000)
POINT_DEC:       +51.589d {+51d 35' 19"} (J2000)
POINT_ROLL:      262.182d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13932.87 SOD {03:52:12.87} UT,   95.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.834
N_STARS:         190
X_OFFSET:        272 [pixels]
Y_OFFSET:        280 [pixels]
X_MAX:           1711 [pixels]
Y_MAX:           1719 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00510341000msufc0095.fits
SUN_POSTN:       273.27d {+18h 13m 04s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.14d {+18h 36m 33s}  -20.95d {-20d 57' 15"}
MOON_DIST:       108.80 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.08, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:08:25 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.110d {+00h 52m 26s} (J2000)
POINT_DEC:       +51.589d {+51d 35' 19"} (J2000)
ROLL:            262.182d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13932.87 SOD {03:52:12.87} UT,   95.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     346477940
X_OFFSET:        576 [pixels]
Y_OFFSET:        827 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       736
Y_GRB_POS:       987
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0103.fits
SUN_POSTN:       273.27d {+18h 13m 04s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.15d {+18h 36m 35s}  -20.95d {-20d 57' 11"}
MOON_DIST:       108.80 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.08, 41.52 [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).  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:08:45 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.110d {+00h 52m 26s} (J2000)
POINT_DEC:       +51.589d {+51d 35' 19"} (J2000)
ROLL:            262.182d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13932.87 SOD {03:52:12.87} UT,   95.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     346477940
X_OFFSET:        576 [pixels]
Y_OFFSET:        827 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       736
Y_GRB_POS:       987
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0103.fits
SUN_POSTN:       273.27d {+18h 13m 04s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.15d {+18h 36m 36s}  -20.95d {-20d 57' 09"}
MOON_DIST:       108.80 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.08, 41.52 [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.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:10:16 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.1550d {+00h 52m 37.19s} (J2000),
                  13.3278d {+00h 53m 18.66s} (current),
                  12.4371d {+00h 49m 44.91s} (1950)
GRB_DEC:         +51.5720d {+51d 34' 19.2"} (J2000),
                 +51.6369d {+51d 38' 12.9"} (current),
                 +51.3005d {+51d 18' 01.8"} (1950)
GRB_ERROR:       0.8 [arcsec radius, statistical only]
GRB_MAG:         19.42 +/- 0.20 [mag]
FILTER:          7, U
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  13932.00 SOD {03:52:12.00} UT,   94.2 [sec] since BAT Trigger Time
SUN_POSTN:       273.27d {+18h 13m 04s}  -23.40d {-23d 24' 11"}
SUN_DIST:        114.26 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.17d {+18h 36m 40s}  -20.95d {-20d 57' 02"}
MOON_DIST:       108.81 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.12,-11.30 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       36.10, 41.49 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The UVOT position is 7.2 arcsec from the XRT position.  
COMMENTS:        There is a bright star (mag=6.21) 9.87 arcmin from the UVOT position.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN Circular #12720
M. H. Siegel (PSU), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), D. Grupe (PSU), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), C. A. Swenson (PSU), T. N. Ukwatta (MSU) and B.-B. Zhang (PSU) report on behalf of the Swift Team:
At 03:50:37 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111225A (trigger=510341). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 13.102, +51.589 which is
```
   RA(J2000) = 00h 52m 24s
   Dec(J2000) = +51d 35' 19"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The immediately available lightcurve was truncated for contact with the ground station. The BAT lightcurve showed a rise at around T-10 seconds with flux continuing at least until T+8 seconds, the limit of of the immediately available data. The peak count rate was ~1300 counts/sec (15-350 keV), at ~-2 sec after the trigger.
The XRT began observing the field at 03:52:05.9 UT, 88.1 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 13.1548, 51.5741 which is equivalent to:
```
   RA(J2000)  = +00h 52m 37.15s
   Dec(J2000) = +51d 34' 26.8"
```
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 129 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 2.96e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 95 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	00:52:37.21 =  13.15503
  DEC(J2000) = +51:34:19.5  =  51.57207
```
with a 90%-confidence error radius of about 0.75 arc sec. This position is 7.3 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.42 with a 1-sigma error of about 0.20. No correction has been made for the expected extinction corresponding to E(B-V) of 0.26.
Burst Advocate for this burst is M. H. Siegel (siegel AT astro.psu.edu). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:13:18 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.592d {+51d 35' 29"} (J2000)
POINT_ROLL:      262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14192.16 SOD {03:56:32.16} UT,   354.4 [sec] since BAT Trigger Time
FILTER:          2, UVW2
BKG_MEAN:        0.138
N_STARS:         85
X_OFFSET:        16 [pixels]
Y_OFFSET:        267 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1706 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw00510341000msufc0354.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.20d {+18h 36m 48s}  -20.95d {-20d 56' 46"}
MOON_DIST:       108.76 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:14:10 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.592d {+51d 35' 29"} (J2000)
ROLL:            262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14192.16 SOD {03:56:32.16} UT,   354.4 [sec] since BAT Trigger Time
FILTER:          2, UVW2
EXPOSURE_ID:     346478199
X_OFFSET:        576 [pixels]
Y_OFFSET:        827 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       736
Y_GRB_POS:       987
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0362.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.21d {+18h 36m 50s}  -20.95d {-20d 56' 42"}
MOON_DIST:       108.76 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [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.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:12:58 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.592d {+51d 35' 29"} (J2000)
POINT_ROLL:      262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14192.16 SOD {03:56:32.16} UT,   354.4 [sec] since BAT Trigger Time
FILTER:          2, UVW2
BKG_MEAN:        0.138
N_STARS:         85
X_OFFSET:        16 [pixels]
Y_OFFSET:        267 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1706 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw00510341000msufc0354.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.20d {+18h 36m 47s}  -20.95d {-20d 56' 48"}
MOON_DIST:       108.77 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:13:51 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.592d {+51d 35' 29"} (J2000)
ROLL:            262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14192.16 SOD {03:56:32.16} UT,   354.4 [sec] since BAT Trigger Time
FILTER:          2, UVW2
EXPOSURE_ID:     346478199
X_OFFSET:        576 [pixels]
Y_OFFSET:        827 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       736
Y_GRB_POS:       987
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0362.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.20d {+18h 36m 49s}  -20.95d {-20d 56' 43"}
MOON_DIST:       108.76 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [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).  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:15:25 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.591d {+51d 35' 28"} (J2000)
POINT_ROLL:      262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14701.26 SOD {04:05:01.26} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.456
N_STARS:         190
X_OFFSET:        16 [pixels]
Y_OFFSET:        267 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1706 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00510341000msufc0863.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.22d {+18h 36m 53s}  -20.94d {-20d 56' 35"}
MOON_DIST:       108.75 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:15:53 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.591d {+51d 35' 28"} (J2000)
POINT_ROLL:      262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14701.26 SOD {04:05:01.26} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.456
N_STARS:         190
X_OFFSET:        16 [pixels]
Y_OFFSET:        267 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1706 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00510341000msufc0863.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.23d {+18h 36m 54s}  -20.94d {-20d 56' 33"}
MOON_DIST:       108.75 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:16:02 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.591d {+51d 35' 28"} (J2000)
ROLL:            262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14701.26 SOD {04:05:01.26} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     346478708
X_OFFSET:        575 [pixels]
Y_OFFSET:        826 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       735
Y_GRB_POS:       986
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0871.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.23d {+18h 36m 54s}  -20.94d {-20d 56' 32"}
MOON_DIST:       108.74 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [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).  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:16:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     510341,   Seg_Num: 0
POINT_RA:         13.113d {+00h 52m 27s} (J2000)
POINT_DEC:       +51.591d {+51d 35' 28"} (J2000)
ROLL:            262.187d
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14701.26 SOD {04:05:01.26} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     346478708
X_OFFSET:        575 [pixels]
Y_OFFSET:        826 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       735
Y_GRB_POS:       986
BINNING_INDEX:   1
IM_URL:          sw00510341000msuni0871.fits
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.24 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.23d {+18h 36m 55s}  -20.94d {-20d 56' 31"}
MOON_DIST:       108.74 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.09,-11.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       36.09, 41.52 [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.  
COMMENTS:        There is a bright star (mag=6.21) 7.95 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 25 Dec 11 04:17:10 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     510341,   Seg_Num: 0
GRB_RA:           13.1545d {+00h 52m 37.08s} (J2000),
                  13.3273d {+00h 53m 18.54s} (current),
                  12.4366d {+00h 49m 44.79s} (1950)
GRB_DEC:         +51.5716d {+51d 34' 17.7"} (J2000),
                 +51.6365d {+51d 38' 11.4"} (current),
                 +51.3001d {+51d 18' 00.3"} (1950)
GRB_ERROR:       2.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15920 TJD;   359 DOY;   11/12/25
IMG_START_TIME:  14297.00 SOD {03:58:17.00} UT,   459.2 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       273.27d {+18h 13m 05s}  -23.40d {-23d 24' 10"}
SUN_DIST:        114.26 [deg]   Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN:      279.24d {+18h 36m 57s}  -20.94d {-20d 56' 26"}
MOON_DIST:       108.76 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      123.12,-11.30 [deg] galactic lon,lat of the burst
ECL_COORDS:       36.10, 41.49 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        There is a bright star (mag=6.21) 9.85 arcmin from the XRT position.  
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 Circular #12721
Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR), Boer M. (OHP-CNRS), Atteia J.L. (IRAP-CNRS-OMP) report:
We imaged the field of GRB 111225A detected by SWIFT (trigger 510341) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
The observations started 59.7s after the GRB trigger (15.5s after the notice). The elevation of the field decreased from 10 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 (Siegel et al. CGNC 12720) with a limiting magnitude of: t0+59.7s to t0+119.7s : R > 15.9
The second image is 30.0s exposure in tracking mode: t0+134.4s to t0+164.4s : R > 16.2
We co-added a series of exposures: t0+134.4s to t0+326.7s : R > 18.0
No OT was detected in the next images until t0+1700s at the level R > 17.6.
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
This message may be cited.
GCN Circular #12722
Klotz A. (IRAP-OMP), Gendre B. (ASDC/INAF-OAR), Boer M. (OCA-CNRS), Atteia J.L. (IRAP-OMP) report:
We imaged the field of GRB 111225A detected by SWIFT (trigger 510341) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
Following the previous report (Klotz et al. GCNC 12721) we co added only long exposure images obtained later than 1100 seconds after the trigger and we detect marginally the UVOT OT mentioned by Siegel et al. (CGNC 12720):
t0+1100s to t0+1800s : R = 19.1 (+/- 0.6)
The OT detected by TAROT has a comparable magnitude as NOMAD1 1415-0026136 locaded 20 arcsec from the UVOT OT position.
This message may be cited.
GCN Circular #12723
Adria C. Updike (Dickinson College), Dieter H. Hartmann (Clemson University), Peter A. Milne (Steward Observatory) and G. Grant Williams (MMT Observatory) report:
We observed the field of GRB 111225A (Siegel et al., GCN 12720) with the 0.6m Super-LOTIS telescope located at Kitt Peak National Observatory under good conditions and airmass of 1.1. Observations began 49 seconds after the trigger. The OT (Siegel et al. GCN 12720, Klotz et al. GCN 12722) is marginally detected in 300 seconds of stacked images (with a midtime of 480 seconds after the trigger) with an R-band magnitude of 19.9 +/- 0.2 (on comparison to the USNO B1.0 catalog). Observations are continuing.
This message may be cited.
GCN Circular #12724
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1857 s of XRT Photon Counting mode data and 2 UVOT images for GRB 111225A, 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 = 13.15557, +51.57157 which is equivalent to:
```
RA (J2000): 00h 52m 37.34s
Dec (J2000): +51d 34' 17.6"
```
with an uncertainty of 2.2 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 #12725
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 111225A ( Siegel et al., GCN 12720) with Xinglong TNT telescope from 10:50:40 (UT), about 7 hour after the burst.
Preliminary analysis shows that the brightness of the optical afterglow counterpart ( Siegel et al., GCN 12720, Klotz et al. GCN 12722, Adria et al. GCN 12723) has decayed to about R~20.4 mag relatively to USNO B1.O R2 mag, at the mean time of 7.7 hour after the burst.
More observations are encouraged.
This message may be cited.
Thanks for the observation assistant of TNT telescope at Xinglong observatory.
GCN Circular #12726
W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. H. Siegel (PSU) M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 111225A (trigger #510341) (Siegel, et al., GCN Circ. 12720). The BAT ground-calculated position is RA, Dec = 13.158, 51.573 deg which is
```
  RA(J2000)  =  00h 52m 37.9s 
  Dec(J2000) = +51d 34' 21.8" 
```
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 93%.
The mask-weighted light curve shows a FRED like structure with the emission starting at ~T-15 sec, peaking at ~T-5 sec and ending at ~T+150 sec. T90 (15-350 keV) is 106.8 +- 26.7 sec (estimated error including systematics).
The time-averaged spectrum from T-14.28 to T+111.24 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.70 +- 0.15. The fluence in the 15-150 keV band is 1.3 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T-4.40 sec in the 15-150 keV band is 0.7 +- 0.1 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/510341/BA/
GCN Circular #12727
B.-B. Zhang and M. H. Siegel (PSU) reports on behalf of the Swift-XRT team:
We have analysed 10 ks of XRT data for GRB 111225A (Siegel et al. GCN Circ. 12720), from 94 s to 23.3 ks after the BAT trigger. The data comprise 556 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 12724).
The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=0.6 (+0.4, -0.3). At T+114 s the decay steepens to an alpha of 1.83 (+0.10, -0.09). The light curve breaks again at T+353 s to a decay with alpha=3.1 (+/-0.5), before a final break at T+590 s s after which the decay index is 1.80 (+0.11, -0.12). An early time flare (from T+214.6 to T+321.8 s) and a possible late time flare (from ~T+20000s) are excluded from the fit.
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.43 (+/-0.07). The best-fitting absorption column is 2.09 (+0.16, -0.15) x 10^21 cm^-2, in excess of the Galactic value of 1.7 x 10^21 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.71 (+0.17, -0.15) and a best-fitting absorption column consistent with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.5 x 10^-11 (5.7 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     0 (+7.7, -0) x 10^20 cm^-2
Galactic foreground: 1.7 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.71 (+0.17, -0.15)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00510341.
This circular is an official product of the Swift-XRT team.
GCN Circular #12728
J. Gorosabel (IAA-CSIC), P. Martorell (Obs. Guirguillano), P. Kubanek (IAA-CSIC & U. Valencia), S. Mottola (DLR, Berlin), report on behalf of a larger collaboration:
"We have observed the field of GRB 111225A (Siegel et al. GCNC 12720) with the 1.23m CAHA telescope. The observations were carried out in Dec 25.74725 - 25.83561 UT (14.1--16.2 hours post burst) in the R-band with a total exposure time of 11x300+15x180s. We detect the optical afterglow of the burst with an R-band magnitude of R=21.60+/-0.16, with respect to the USNO B1.0 catalogue."
GCN Circular #12729
T. Sakamoto (UMBC/GSFC), D. Donato (ORAU/GSFC), N. Gehrels (GSFC), T. Okajima (GSFC), Y. Urata (NCU)
We observed the field of GRB 111225A detected by Swift (trigger #510341; Siegel et al., GCN Circ. 12720) with the 14-inch Goddard Robotic Telescope (GRT) located at the Goddard Geophysical and Astronomical Observatory (http://cddisa.gsfc.nasa.gov/ggao/).
A total 20 images of 60 sec (10 images), 180 sec (5 images) and 300 sec (5 images) exposures were taken in the R filter starting from December 25 03:52:12 (UT) about 94 seconds after the trigger (50 seconds after the BAT position notice) and stopped on December 25 04:43:53 (UT). We do not detect the optical afterglow both in the individual images and the stacked image inside the enhanced XRT position (Evans et al., GCN #12724). The estimated upper limit of the combined image (total exposure of 3000 sec) is ~18.5 mag using the USNO-B1 catalog.
GCN Circular #12730
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 111225A (Siegel et al., GCNC 12720) 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 2011-12-25 09:00:08 UT (~5.2 hours after the burst). We did not find any new point source within the enhanced XRT error circle (Evans et al., GCNC 12724) and could not detect the previously reported afterglow (Klotz et al., GCNC 12722; Updike et al., GCNC 12723) in g' and Ic 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'     Ic
------------------------------------------------------
0.25569    09:58:49  5700.0     >20.2  >19.6
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12731
A. N. Morgan (UC Berkeley) reports:
We observed the field of GRB 111225A (Siegel et al., GCN 12720) with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at 2011-12-26 01h13m05 UT, ~21.35 hr after the Swift Trigger. In mosaics taken simultaneously in the J, H, and Ks filters, we do not detect the optical afterglow (Siegel et al., GCN 12720; Klotz et al., GCN 12722; Updike et al., GCN 12723; Xin et al., GCN 12725; Gorosabel et al., GCN 12728).
The preliminary photometry yields:
```
post burst
t_mid(h) exp.(s) filt  U. Limit (3 sig)
22.45    4774    J     > 18.4
22.45    4774    H     > 17.6
22.45    4774    Ks    > 16.9
```
All magnitudes are given in the Vega system, calibrated to 2MASS. No correction for Galactic extinction has been made to the above reported values.
GCN Circular #12733
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 GRB111225A (Siegel et al., GCN 12720) with the Low-Resolution Imaging Spectrometer (LRIS) mounted on the 10 m Keck I telescope beginning at 4:56 UT on 2012 Dec 26 (~ 25.1 hours after the Swift BAT trigger). We detect the optical afterglow in both the g' and R-band filters, with an approximate magnitude at this time of R ~ 23.2 (estimated uncertainty of 0.3 mag, due largely to preliminary calibration with respect to the USNO-B1 catalog). Compared with previously reported detections (Xin et al, GCN 12725, Gorosabel et al., GCN 12728), this suggests a steep fading of the afterglow emission at this late time (power-index alpha ~ 2.5).
GCN Circular #12735
M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111225A 95 s after the BAT trigger (Siegel et al., GCN Circ. 12720). A source consistent with the XRT position is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
   RA  (J2000) =  00:52:37.22 =  13.15510 (deg.)
   Dec (J2000) = +51:34:19.5  =  51.57208 (deg.)
```
with an estimated uncertainty of 0.67 arc sec. (radius, 90% confidence).
The afterglow has not been detected since the first orbit. Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

u (fc)              95          345          246         19.46 +/- 0.17
v                  610        18443         2140        >21.1
u                 4385        16744         1475        >20.66 
uvw1               659        12668         1212        >20.4
uvm2               634        11879         1337        >20.5
uvw2               354        17652         1780         21.36 +/- 0.31
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.26 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12740
TITLE: T100 observations of GRB 111225A
Sonbas, E.(Adiyaman Univ.), Guver, T. (Sabanci Univ.), Gogus, E. (Sabanci Univ.), Uysal, O. (Akdeniz Univ.), Sahin T. (Akdeniz Univ.), Eker, Z. (TUG), T. Ozisik (TUG) on behalf of a larger collaboration.
We observed the field of GRB 111225A (Siegel et al., GCN #12720) with the 1.0 meter T100 telescope (TUBITAK National Observatory, Antalya - Turkey), starting on December 25, 21:14 UT (~ 17 hours after the trigger). We obtained 3 x 60 s + 2 x 300 s exposures with R and B filters under moderate weather conditions (seeing 1.8").
We do not detect an optical afterglow at the enhanced XRT error circle reported by Evans et al., GCN #12724 in the combined R and B band images. We determine the following 3-sigma upper limits (calibrated to R2 and B2 mag. of USNO-B1) in the two bands:
```
   t - t0        Exposure (s)          Filter              mag.
~17.4 h           780                    R                 > 22.5
~17.5 h           780                    B                 > 21.9
```
We are grateful to the TUBITAK National Observatory staff for promptly scheduling the observations and their technical support.
GCN Circular #12772
T. N. Ukwatta (MSU), E. Sonbas (GSFC/Adiyaman Univ.), T. Sakamoto (GSFC/UMBC), N. Gehrels (GSFC), J. Linnemann (MSU), K. Tollefson (MSU), and U. Abeysekara (MSU)
We observed the field of Swift GRB 111225A (Siegel et al., GCN 12720) with the Lightbuckets 0.43m rental telescope LB-0002 in South Alpen, France. Ten 60 s observations were carried out in the R filter starting 2011-12-25 at 17:01:47 UT (~ 47 ks after the GRB trigger).
We do not detect the optical afterglow both in the individual images and in the stacked image inside the XRT location. Our upper-limit based on the stacked observation (using the USNO-B1 catalog) is given below.
```
Time after trigger       Exposure (s)   Filter     Magnitude
  13.2 hours             10 x 60          R         > 19.7
```
GCN Circular #12793
V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of GRB 111125A (Siegel et al. GCN 12720) with Shajn telescope of CrAO observatory on Dec. 28 between (UT) 21:28: and 22:38 under a mean seeing of 1.7 arsces. We took several frames with exposure of 60 s in R-band. We clearly detect afterglow of GRB 111225A (Klotz et al. GCN 12722) on a stacked image. A photometry is based on the USNO B1.0 star 1415-0025726 (00 52 35.11 +51 33 58.9, J2000) assuming R=16.50.
```
T_start UT  T0+        Filter, Exposure, OT,  uplim (3 sigma)
                  (mid, d)            (s)


21:28:14     3.7590    R       62x60      22.51 +/- 0.10    24.0
```
GCN Circular #12803
J. Wren, W. T. Vestrand, P. Wozniak, and H. Davis of Los Alamos National Laboratory report:
The RAPTOR network of robotic optical telescopes responded to Swift trigger 510341 (GRB 111225A, Siegel et al., GCN 12720). Unfiltered observations of the source location began at 03:51:27.2 UTC, 49.4 seconds after the BAT trigger time. The initial short exposures during the first two mintues of our response sequence do not clearly show the counterpart. However, stacking those images, 8 5-second exposures taken between 03:51:37.6 UTC and 03:52.46.0 UTC, gives a 5-sigma detection at counterpart location (Klotz et al., GCN 12722, and Updike et al., GCN 12723). Based on comparison to the USNO-B1 R-band, the measured brightness is R~18.7 +\- 0.3 at a t-mid of 03:52:12 UTC, 94 seconds after the Swift BAT trigger.
GCN Circular #12808
V.V.Golovnya, L.M.Kizyun, L.K.Pakuliak (Main Astro Obs, Kyiv) report:
We have undertaken the review of the sky area in vicinity of=20 GRB 111225A (M. H. Siegel, GCN Circ.12735) on astronegatives, collected in Ukrainian NAS Main astronomical observatory plate=20 archive (1976-1996). All the plates with the possible object=20 appearance are digitized using Microtek ScanMaker 9800XL TMA=20 and Epson Expression 10000XL flatbed scanners and have been=20 placed into Golosiiv Plate Archive database DBGPA with open=20 access to them.
```
 	The list of plates is given in the table:
YYYYMMDD/TimeUT	--Plates--	Exp.	LimMag	Star USNOA2=20
19831109/192323	GUA040C000250A	13.5	15.70	1350-00882390
19831109/194519	GUA040C000251A	13.0	15.20	1350-00878189
19840828/001418	GUA040C000469A	16.0	15.70	1350-00882390
19841019/211508	GUA040C000511A	15.9	15.70	1350-00882390
19841020/205803	GUA040C000525A	16.0	14.85	1350-00882046
Plates: =96the plates archive identifier of DWA (D/F=3D400/2000,=20
GUA040C M=3D103"/mm) of the Ukrainian NAS Main Astro obs.
        (Marsden's number - 83) the plate number [1].
Exp.   - Duration of the maximum exposure (minutes).=20
LimMag - Limited V mag, derived in the 20 minutes area around=20
       the location given in GCN Circ.12735:=20
       RA (J2000) =3D 00:52:37.22, Dec (J2000) =3D +51:34:19.5
Star USNOA2 - Comparison star.
```
The preview images of 5 areas together with =20 the 20x20 min.of arc area from SkyMap can be found in =20 http://gua.db.ukr-vo.org/img/grb/111225A/index.html
The images with full resolution are available via e-mail on demand.
References: 1.L.Pakuliak DATABASE of GOLOSIIV PLATE ARCHIVE (DBGPA V2.0), http://gua.db.ukr-vo.org
GCN Circular #12893
A.Volnova (SAI MSU), E. Klunko (ISTP), M. Andreev, A. Sergeev (Terskol Branch of INASAN), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the field of GRB 111225A (Siegel et al., GCN 12720) with AZT-33IK telescope of Sayan observatory (Mondy) on Dec. 25 between (UT) 17:37:41 - 18:25:58 in R filter under mean seeing (FWHM) of about 2.0".
We also observed the field with Zeiss-2000 telescope of Mt. Terskol observatory on Dec. 26 between (UT) 17:37:23-18:46:37 in BRI filters under poor seeing (FWHM) of about 4.4". On stacked images of both epochs we did not find an optical counterpart (Siegel et al., GCN 12720; Klotz et al., GCN 12722; Adria et al., GCN 12723; Wren et al., GCN 12803).
The photometry is based on the USNO-B1.0 star 1415-0025726 (J2000) 00:52:35.11 +51:33:58.9, assuming B = 17.56, R =16.50, I = 16.20:
```
T0+,        Filter,  Exposure,   OT,   UL(3 sigma),    Telescope
(mid, d)             (s)
0.63278     R     24 x 120   n/d   22.5            AZT-33IK
1.58789     B     10 x 90     n/d   22.0            Zeiss-2000
1.60285     R     10 x 90     n/d   21.5            Zeiss-2000
1.61677     I      10 x 90     n/d   20.5            Zeiss-2000
```
Upper limits above are consistent with upper limits of R~22.5 reported by Sonbas et al. (GCN 12740) and observations of the afterglow at R ~ 23.2 on ~ 1day after burst trigger (Cenko et al., GCN 12733). Taking into account the positive detection of the afterglow on 3.7590 days at R~22.5 (Rumyantsev et al., GCN 12793) one can suggest a strong rebrightening of the afterglow which is a rare case of late afterglow (3.7590 days) of an apparently nearby burst (cf. UVOT optical detection in uvw2 filter (Siegel, GCN 12735).
GCN Report 408.1
GCN_Report 408.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_408_1.pdf by M.H. Siegel at PSU titled: "Swift Observations of GRB 111225A"
GCN Circular #16079
C.C. Thoene (IAA-CSIC) and A. de Ugarte Postigo (IAA-CSIC, DARK/NBI) report on behalf of a larger collaboration:
We observed the Christmas burst of 2011, GRB 111225A (Siegel et al. GCN 12720), with the 10.4m GTC telescope+OSIRIS on December 25, 2011 at a mean time 23:27 UT, 19.61 hrs after the burst. The observations consisted of 2x1800 s exposure with grism R1000B, covering the wavelength range from 3700 to 7870A with a resolution of around R=1000.
Initial analysis of the spectrum revealed continuum emission over the complete range but no significant features neither in absorption nor emission. However, a more careful analysis recently performed on the data with an improved pipeline revealed faint emission features of [OII], H-beta and [OIII], and marginal absorption of CaII at a common redshift of z=0.297, which we therefore identify as the redshift of the GRB.
We apologise for the late notification. Better late than never.
1606.01983 from 8 Jun 16
Yuu Niino et al.: The redshifted selected sample of long gamma-ray burst host galaxies: the complete metallicity measurements at $z \leq 0.41$
We present the complete list of host galaxy metallicities for all long GRBs whose redshifts were determined to be $\leq 0.41$ before the end of March 2014, including newly obtained spectroscopic datasets of the host galaxies of GRB 060614, 090417B, and 130427A. We compare the metallicity distribution of the redshift selected complete sample to the model predictions, and constrain the relation between metallicity and GRB occurrence. We take account of spatial variation of metallicities among star forming regions within a galaxy. We found that the models, in which only low-metallicity stars produce GRBs with a sharp cutoff of GRB production efficiency around 12+log(O/H) $\sim$ 8.2, can well reproduce the observed distribution, while the models with moderate (or no) metallicity dependence are not consitistent with the observations. This is the first fair estimate of the metallicity distribution of GRB host galaxies based on the redshift selected complete sample in the {\it Swift} era. We also discuss possible sampling biases we may suffer by collecting long GRBs whose redshifts are known, presenting the photometric observations of the host galaxy of GRB 111225A at $z = 0.297$ whose redshift has been undetermined until $\sim$ 2.3 years after the burst.

Back to JG's homepage

Jochen Greiner, last update: 08-Jun-2016 [Disclaimer]