Gamma-ray Burst 111008A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:13:19 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.454d {+04h 01m 49s} (J2000),
                  60.568d {+04h 02m 16s} (current),
                  59.969d {+03h 59m 53s} (1950)
GRB_DEC:         -32.689d {-32d 41' 18"} (J2000),
                 -32.656d {-32d 39' 22"} (current),
                 -32.827d {-32d 49' 36"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5378 [cnts]    Image_Peak=154 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   155     E_range: 50-350 keV
BKG_INTEN:       25002 [cnts]
BKG_TIME:        79960.55 SOD {22:12:40.55} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15842 TJD;   281 DOY;   11/10/08
GRB_TIME:        79978.28 SOD {22:12:58.28} UT
GRB_PHI:         139.45 [deg]
GRB_THETA:        45.70 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     36.23 [sigma]
IMAGE_SIGNIF:    9.07 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +3  +0  +0  +0 +51  +0 
SUN_POSTN:       194.07d {+12h 56m 17s}   -6.02d {-06d 00' 59"}
SUN_DIST:        121.32 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.23d {+22h 40m 55s}   -2.89d {-02d 53' 26"}
MOON_DIST:        80.31 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.58,-48.71 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       47.75,-51.88 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 65.02,-19.87 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:15:01 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.4491d {+04h 01m 47.78s} (J2000),
                  60.5633d {+04h 02m 15.18s} (current),
                  59.9642d {+03h 59m 51.39s} (1950)
GRB_DEC:         -32.7098d {-32d 42' 35.2"} (J2000),
                 -32.6775d {-32d 40' 39.1"} (current),
                 -32.8481d {-32d 50' 53.2"} (1950)
GRB_ERROR:       4.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       4.01e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.44 [sigma]
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80069.81 SOD {22:14:29.81} UT,   91.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.61 237.23 261.45 243.71
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       194.07d {+12h 56m 18s}   -6.02d {-06d 01' 00"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.24d {+22h 40m 59s}   -2.89d {-02d 53' 06"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.61,-48.72 [deg] galactic lon,lat of the burst
ECL_COORDS:       47.73,-51.90 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.29 arcmin from the BAT position.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:15:12 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.4491d {+04h 01m 47.7s} (J2000),
                  60.5633d {+04h 02m 15.1s} (current),
                  59.9642d {+03h 59m 51.3s} (1950)
GRB_DEC:         -32.7098d {-32d 42' 35.2"} (J2000),
                 -32.6775d {-32d 40' 39.1"} (current),
                 -32.8481d {-32d 50' 53.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       131 [cnts]
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80069.81 SOD {22:14:29.81} UT,   91.5 [sec] since BAT Trigger Time
CENTROID_X:      323.73,  raw= 324  [pixels]
CENTROID_Y:      265.95,  raw= 266  [pixels]
ROLL:            122.48 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -75.54
GRB_POS_XRT_Z:   47.22
IMAGE_URL:       sw00505054000msxps_rw.img
SUN_POSTN:       194.07d {+12h 56m 18s}   -6.02d {-06d 01' 00"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.25d {+22h 40m 59s}   -2.88d {-02d 53' 04"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.61,-48.72 [deg] galactic lon,lat of the burst
ECL_COORDS:       47.73,-51.90 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:15:19 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.4491d {+04h 01m 47.7s} (J2000),
                  60.5633d {+04h 02m 15.1s} (current),
                  59.9642d {+03h 59m 51.3s} (1950)
GRB_DEC:         -32.7098d {-32d 42' 35.2"} (J2000),
                 -32.6775d {-32d 40' 39.1"} (current),
                 -32.8481d {-32d 50' 53.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       131 [cnts]
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80069.81 SOD {22:14:29.81} UT,   91.5 [sec] since BAT Trigger Time
CENTROID_X:      323.73,  raw= 324  [pixels]
CENTROID_Y:      265.95,  raw= 266  [pixels]
ROLL:            122.48 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -75.54
GRB_POS_XRT_Z:   47.22
IMAGE_URL:       sw00505054000msxps_rw.img
SUN_POSTN:       194.07d {+12h 56m 18s}   -6.02d {-06d 01' 00"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.25d {+22h 40m 59s}   -2.88d {-02d 53' 03"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.61,-48.72 [deg] galactic lon,lat of the burst
ECL_COORDS:       47.73,-51.90 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:17:01 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.454d {+04h 01m 49s} (J2000),
                  60.568d {+04h 02m 16s} (current),
                  59.969d {+03h 59m 53s} (1950)
GRB_DEC:         -32.689d {-32d 41' 18"} (J2000),
                 -32.656d {-32d 39' 22"} (current),
                 -32.827d {-32d 49' 36"} (1950)
GRB_DATE:        15842 TJD;   281 DOY;   11/10/08
GRB_TIME:        79978.28 SOD {22:12:58.28} UT
TRIGGER_INDEX:   155
GRB_PHI:         139.45 [deg]
GRB_THETA:        45.70 [deg]
DELTA_TIME:      -11.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     36.23 [sigma]
IMAGE_SIGNIF:    9.07 [sigma]
LC_URL:          sw00505054000msb.lc
SUN_POSTN:       194.07d {+12h 56m 18s}   -6.02d {-06d 01' 02"}
SUN_DIST:        121.32 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.26d {+22h 41m 02s}   -2.88d {-02d 52' 43"}
MOON_DIST:        80.29 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.58,-48.71 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       47.75,-51.88 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 65.02,-19.87 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:17:35 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.476d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.699d {-32d 41' 54"} (J2000)
POINT_ROLL:      122.481d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80077.10 SOD {22:14:37.10} UT,   98.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.545
N_STARS:         48
X_OFFSET:        344 [pixels]
Y_OFFSET:        624 [pixels]
X_MAX:           1303 [pixels]
Y_MAX:           1583 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00505054000msufc0098.fits
SUN_POSTN:       194.08d {+12h 56m 18s}   -6.02d {-06d 01' 03"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.26d {+22h 41m 03s}   -2.88d {-02d 52' 37"}
MOON_DIST:        80.31 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.78,-51.90 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:18:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.476d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.699d {-32d 41' 54"} (J2000)
POINT_ROLL:      122.481d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80077.10 SOD {22:14:37.10} UT,   98.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.545
N_STARS:         48
X_OFFSET:        344 [pixels]
Y_OFFSET:        624 [pixels]
X_MAX:           1303 [pixels]
Y_MAX:           1583 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00505054000msufc0098.fits
SUN_POSTN:       194.08d {+12h 56m 18s}   -6.02d {-06d 01' 03"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.27d {+22h 41m 04s}   -2.88d {-02d 52' 31"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.78,-51.90 [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:     Sat 08 Oct 11 22:18:58 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.476d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.699d {-32d 41' 54"} (J2000)
ROLL:            122.481d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80077.10 SOD {22:14:37.10} UT,   98.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     339804884
X_OFFSET:        778 [pixels]
Y_OFFSET:        1041 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1201
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0106.fits
SUN_POSTN:       194.08d {+12h 56m 18s}   -6.02d {-06d 01' 04"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.27d {+22h 41m 06s}   -2.87d {-02d 52' 21"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.78,-51.90 [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:     Sat 08 Oct 11 22:19:17 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.476d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.699d {-32d 41' 54"} (J2000)
ROLL:            122.481d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80077.10 SOD {22:14:37.10} UT,   98.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     339804884
X_OFFSET:        778 [pixels]
Y_OFFSET:        1041 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1201
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0106.fits
SUN_POSTN:       194.08d {+12h 56m 18s}   -6.02d {-06d 01' 04"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.28d {+22h 41m 07s}   -2.87d {-02d 52' 17"}
MOON_DIST:        80.30 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.78,-51.90 [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 #12423
C. J. Saxton (UCL-MSSL), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL), O. M. Littlejohns (U Leicester), F. E. Marshall (NASA/GSFC), C. Pagani (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL) and C. A. Swenson (PSU) report on behalf of the Swift Team:
At 22:12:58 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111008A (trigger=505054). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 60.454, -32.689, which is
```
   RA(J2000)  =  04h 01m 49s
   Dec(J2000) = -32d 41' 18"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows 3 sets of peaks with a total duration of about 70 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 22:14:29.8 UT, 91.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 60.4491, -32.7098 which is equivalent to:
```
   RA(J2000)  = 04h 01m 47.78s
   Dec(J2000) = -32d 42' 35.2"
```
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This location is 76 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.
UVOT took a finding chart exposure of 150 seconds with the White filter starting 98 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 0.01.
Burst Advocate for this burst is C. J. Saxton (cjs2 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:     Sat 08 Oct 11 22:25:27 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
POINT_ROLL:      122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80289.29 SOD {22:18:09.29} UT,   311.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.459
N_STARS:         43
X_OFFSET:        458 [pixels]
Y_OFFSET:        721 [pixels]
X_MAX:           1417 [pixels]
Y_MAX:           1680 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00505054000msufc0311.fits
SUN_POSTN:       194.08d {+12h 56m 19s}   -6.02d {-06d 01' 10"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.32d {+22h 41m 18s}   -2.85d {-02d 51' 06"}
MOON_DIST:        80.27 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:25:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
POINT_ROLL:      122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80289.29 SOD {22:18:09.29} UT,   311.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.459
N_STARS:         43
X_OFFSET:        458 [pixels]
Y_OFFSET:        721 [pixels]
X_MAX:           1417 [pixels]
Y_MAX:           1680 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00505054000msufc0311.fits
SUN_POSTN:       194.08d {+12h 56m 19s}   -6.02d {-06d 01' 10"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.33d {+22h 41m 18s}   -2.85d {-02d 51' 03"}
MOON_DIST:        80.27 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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:     Sat 08 Oct 11 22:26:40 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     505054,   Seg_Num: 0
GRB_RA:           60.4521d {+04h 01m 48.50s} (J2000),
                  60.5663d {+04h 02m 15.90s} (current),
                  59.9672d {+03h 59m 52.11s} (1950)
GRB_DEC:         -32.7090d {-32d 42' 32.4"} (J2000),
                 -32.6767d {-32d 40' 36.2"} (current),
                 -32.8473d {-32d 50' 50.3"} (1950)
GRB_ERROR:       2.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80290.00 SOD {22:18:10.00} UT,   311.7 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       194.08d {+12h 56m 19s}   -6.02d {-06d 01' 11"}
SUN_DIST:        121.32 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.33d {+22h 41m 20s}   -2.85d {-02d 50' 52"}
MOON_DIST:        80.24 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.61,-48.71 [deg] galactic lon,lat of the burst
ECL_COORDS:       47.74,-51.90 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:26:56 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
ROLL:            122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80289.29 SOD {22:18:09.29} UT,   311.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     339805096
X_OFFSET:        778 [pixels]
Y_OFFSET:        1041 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1201
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0319.fits
SUN_POSTN:       194.08d {+12h 56m 19s}   -6.02d {-06d 01' 12"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.34d {+22h 41m 21s}   -2.85d {-02d 50' 49"}
MOON_DIST:        80.26 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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:     Sat 08 Oct 11 22:27:08 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
ROLL:            122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80289.29 SOD {22:18:09.29} UT,   311.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     339805096
X_OFFSET:        778 [pixels]
Y_OFFSET:        1041 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1201
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0319.fits
SUN_POSTN:       194.08d {+12h 56m 19s}   -6.02d {-06d 01' 12"}
SUN_DIST:        121.30 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.34d {+22h 41m 21s}   -2.85d {-02d 50' 47"}
MOON_DIST:        80.26 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:32:35 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
POINT_ROLL:      122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80842.98 SOD {22:27:22.98} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.163
N_STARS:         72
X_OFFSET:        218 [pixels]
Y_OFFSET:        481 [pixels]
X_MAX:           1657 [pixels]
Y_MAX:           1920 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00505054000msufc0864.fits
SUN_POSTN:       194.08d {+12h 56m 20s}   -6.02d {-06d 01' 17"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.38d {+22h 41m 31s}   -2.83d {-02d 49' 44"}
MOON_DIST:        80.23 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 08 Oct 11 22:32:56 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
POINT_ROLL:      122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80842.98 SOD {22:27:22.98} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.163
N_STARS:         72
X_OFFSET:        218 [pixels]
Y_OFFSET:        481 [pixels]
X_MAX:           1657 [pixels]
Y_MAX:           1920 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00505054000msufc0864.fits
SUN_POSTN:       194.08d {+12h 56m 20s}   -6.02d {-06d 01' 17"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.38d {+22h 41m 32s}   -2.83d {-02d 49' 40"}
MOON_DIST:        80.23 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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:     Sat 08 Oct 11 22:33:30 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
ROLL:            122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80842.98 SOD {22:27:22.98} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     339805650
X_OFFSET:        777 [pixels]
Y_OFFSET:        1040 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       937
Y_GRB_POS:       1200
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0872.fits
SUN_POSTN:       194.09d {+12h 56m 20s}   -6.02d {-06d 01' 18"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.39d {+22h 41m 33s}   -2.83d {-02d 49' 34"}
MOON_DIST:        80.23 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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:     Sat 08 Oct 11 22:33:57 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505054,   Seg_Num: 0
POINT_RA:         60.474d {+04h 01m 54s} (J2000)
POINT_DEC:       -32.701d {-32d 42' 03"} (J2000)
ROLL:            122.484d
IMG_START_DATE:  15842 TJD;   281 DOY;   11/10/08
IMG_START_TIME:  80842.98 SOD {22:27:22.98} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     339805650
X_OFFSET:        777 [pixels]
Y_OFFSET:        1040 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       937
Y_GRB_POS:       1200
BINNING_INDEX:   1
IM_URL:          sw00505054000msuni0872.fits
SUN_POSTN:       194.09d {+12h 56m 21s}   -6.02d {-06d 01' 18"}
SUN_DIST:        121.31 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      340.39d {+22h 41m 34s}   -2.82d {-02d 49' 29"}
MOON_DIST:        80.23 [deg]
MOON_ILLUM:      91 [%]
GAL_COORDS:      232.60,-48.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       47.77,-51.90 [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 #12424
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), C. J. Saxton (UCL-MSSL), 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+302 sec from the recent telemetry downlink, we report further analysis of BAT GRB 111008A (trigger #505054) (Saxton, et al., GCN Circ. 12423). The BAT ground-calculated position is RA, Dec = 60.439, -32.708 deg which is
```
    RA(J2000)  =  04h 01m 45.3s
    Dec(J2000) = -32d 42' 29.3"
```
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 9%.
The mask-tagged light curve shows three clusters of peaks, each containing at least two subpeaks, and with returns to the baseline between clusters. Each cluster is softer and weaker than the one preceding it. The first cluster runs from T-10 sec to T+10 sec, the second runs from T+28 sec to T+35 sec, and the third from T+58 to T+65 sec. We note that there is a gap in the telemetry from T+180 to T+240 sec, but there is no indication of any emission between the last peak and the gap or after the gap. T90 (15-350 keV) is 63.46 +- 2.19 sec (estimated error including systematics).
The time-averaged spectrum from T-2.64 to T+68.80 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.86 +- 0.09. The fluence in the 15-150 keV band is 5.3 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+0.04 sec in the 15-150 keV band is 6.4 +- 0.7 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/505054/BA/
GCN Circular #12425
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 1125 s of XRT Photon Counting mode data and 1 UVOT images for GRB 111008A, 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 = 60.45094, -32.70947 which is equivalent to:
```
RA (J2000): 04h 01m 48.22s
Dec (J2000): -32d 42' 34.1"
```
with an uncertainty of 1.7 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 #12426
A.J. Levan (Warwick), K. Wiersema, N.R. Tanvir (Leicester) report on behalf of a larger collaboration:
"We observed the field of GRB 111008A (Saxton et al. GCN 12423) with Gemini-South in the r-band. Observations began at 03:12 UT, 5 hours after the BAT trigger. Within the refined XRT error circle (Beardmore GCN 12425) we locate a single object at
```
RA(J2000) 04:04:48.24 
DEC(J2000) -32:42:33.4
```
with an error of 0.5" in each axis. Preliminary photometry against USNO-B1 suggests R~22.8. We suggest this may be the afterglow of GRB 111008A. Further spectroscopic observations are in progress.
We thank the Gemini staff for the rapid and efficient execution of these observations."
GCN Circular #12427
D. Xu (WIS), D. Malesani (DARK/NBI), L.A. Buchhave (NBI), S. Schulze, P. Jakobsson (U. Iceland) report on behalf of a larger collaboration:
We observed the field of GRB 111008A (Saxton et al., GCN 12423) with the 2.5m Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained 2x600 s R-band images, starting at 04:40:07 UT 9th Oct. 2011 (i.e., 6.45 hr after the burst). The optical afterglow reported in Levan et al. (GCN 12426) was detected at R ~ 22.3 mag, calibrated against the #0572-0051383 star (R2=16.77) in the USNO-B1.0 catalog.
GCN Circular #12428
M. Nardini (Milano Bicocca), S. Klose (TLS Tautenburg), J. Greiner (MPE Garching), and P. Afonso (MPE/American River College) report on behalf of the GROND team:
We observed the field of GRB 111008A (Saxton et al., GCN #12423) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG/ESO telescope at La Silla Observatory (Chile).
Observations started at 4:30 UT on October 08, 6.3 hours after the GRB trigger.
We detect a point source within the 1.7 arcsec enhanced Swift-XRT error circle (Beardmore et al., GCN #12425) at coordinates RA, DEC (J2000) = 04:01:48.25, -32:42:33.2 (+/-0.5"), confirming the observations from Gemini (Levan et al., GCN 12426).
Preliminary magnitudes at a meantime of 5:15 UT are (in the AB system):
```
g' > 24.0,
r' = 22.6 +/- 0.1,
i' = 20.9 +/- 0.1,
z' = 19.9 +/- 0.1,
```
indicating a cosmological g-band dropout.
Data are calibrated against GROND zeropoints. Observations are ongoing.
GCN Circular #12429
A.J. Levan (Warwick), K. Wiersema, N.R. Tanvir (Leicester) report for a larger collaboration:
"We obtained optical spectroscopy of the candidate counterpart of GRB 111008A (Saxton et al. GCN 12423, Levan et al. GCN 12426), with GMOS on Gemini-South. Observations were centred at 6000A, and cover the region from 3900-8100A. We see flux from the candidate afterglow down to ~5500A, and a broad absorption feature centred at ~7300A, with a brighter continuum red-ward of this. If interpreted as a DLA then this suggests that the redshift of GRB 111008A is z~5. We also find weak absorption lines of Ly-beta, OI(1302), CII(1334) and SiII (1260.5), consistent with a common redshift of z=5.0.
We note that there was a typographical error in the co-ordinates of GCN 12426, which should have read
```
RA(J2000) 04:01:48.24 
DEC(J2000) -32:42:33.4
```
We thank Javier Gorosabel for pointing this error out, and apologise for any confusion."
GCN Circular #12430
C. Pagani (U Leicester) and C. J. Saxton (UCL-MSSL) report on behalf of the Swift-XRT team:
We have analysed 5.1 ks of XRT data for GRB 111008A (Saxton et al. GCN Circ. 12423), from 81 s to 24.0 ks after the BAT trigger. The data comprise 223 s 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 12425).
The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=7.1 (+0.9, -1.0). At T+103 s the decay flattens to an alpha of 3.22 (+/-0.12). The light curve breaks again at T+311 s to a decay with alpha=0.26 (+/-0.16), before a final break at T+4539 s s after which the decay index is 0.99 (+0.12, -0.11).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.64 (+0.11, -0.10). The best-fitting absorption column is 8.3 (+1.7, -1.6) x 10^20 cm^-2, in excess of the Galactic value of 9.8 x 10^19 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.02 (+/-0.11) and a best-fitting absorption column of 4.3 (+2.1, -2.0) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.0 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     4.3 (+2.1, -2.0) x 10^20 cm^-2
Galactic foreground: 9.8 x 10^19 cm^-2
Excess significance: 3.6 sigma
Photon index:	     2.02 (+/-0.11)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00505054.
This circular is an official product of the Swift-XRT team.
GCN Circular #12431
K. Wiersema (Univ. Leicester), H. Flores (GEPI/Obs. de Paris), V. D'Elia (ASI/ASDC & INAF/OAR), P. Goldoni (APC/Univ. Paris 7 & SAp/CEA), D. Malesani (DARK/NBI), S. D. Vergani (INAF/OABr), A. de Ugarte Postigo (IAA-CSIC), A. J. Levan (Univ. Warwick), B. Milvang-Jensen, J. P. U. Fynbo (DARK/NBI), report on behalf of a larger collaboration:
We observed the optical counterpart of GRB 111008A (Saxton et al., GCN 12423; Levan et al., GCN 12426; Xu et al., GCN 12427; Nardini et al., GCN 12428), using the X-shooter spectrograph mounted on the ESO-VLT. Observations started on 2011 October 9.247 UT (7.71 hr after the GRB), with a total exposure time of 2 hr, covering the wavelength range 3000-25000 AA.
Continuum is clearly detected redwards of ~7600 AA, with several, strong superimposed absorption features, consistent with a commom redshift z = 4.9898. Among them, we note several Si II and Fe II transitions, the CIV doublet, the Mg II doublet (in the H band), and several fine-structure lines commonly observed in GRB afterglow spectra (such as Si II*, S II*, O I*). We also note the presence of an intervening Mg II system at z = 4.61. Our results are thus consistent with the redshift derived by Levan et al. (GCN 12429; see also Nardini et al., GCN 12428).
We acknowledge excellent support from the observing staff in Paranal, in particular Christophe Martayan, Claudio Melo, Leonel Rivas, and Sergio Vera.
GCN Circular #12432
R. Sanchez-Ramirez (IAA-CSIC), J. Gorosabel (IAA-CSIC), M. Cebrian (IAC),= A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), P. Monta=F1es (IAC), A. Rodriguez Anton (IAC), report on behalf of a larger collaboration:
"We observed the field of GRB 111008A (Saxton et al., GCN Circ 12423) wit= h the 82cm IAC80 telescope at the Observatorio del Teide, Tenerife, Spain. = We acquired 22 x 300s I-band images on Oct 9.12973 - Oct 9.21239 UT (average epoch 5.90h after the trigger) . A preliminary analysis of the combined frame shows the source reported by Levan et al. (GCN Circ 12426) with a magnitude of I ~ 20.6 (calibrated against USNO-B1 stars)."
GCN Circular #12433
S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report:
The long GRB 111008A (Swift-BAT trigger #505054: Saxton et al., GCN 12433; Baumgartner et al., GCN 12434) triggered Konus-Wind at T0=3D79981.676s UT (22:13:01.676)
The burst light curve shows an initial pulse which peaked at T0+0.256s and a softer weaker pulse at ~T0+30s. A total burst duration is ~40 s. The emission is seen up to ~2 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB111008_T79981/
As observed by Konus-Wind the burst had a fluence of (9.0 =B1 0.9)x10-6 erg/cm2, and a 256-ms peak flux, measured from T0+0.256 s, of (1.4 =B1 0.3)x10-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the burst (measured from T0 to T0+41.216 s) is best fitted in the 20 keV - 2 MeV range by a simple power-law model with index (2.02 =B1 0.09), chi2 =3D 54.3/59 dof.
The spectrum of the initial pulse (measured from T0 to T0+8.448 s) is best fitted in the 20 keV - 2 MeV range by a power law with exponential cutoff model, for which alpha =3D -1.36 (-0.21, +0.24), and Ep =3D 149(-28, +52) keV, chi2 =3D 38.4/58 dof.
Assuming the redshift z=3D5.0 (Levan et al., GCN 12429; Wiersema et al., GCN 12431) and a standard cosmology model with H_0 =3D 71 km/s/Mpc, Omega_M =3D 0.27, Omega_Lambda =3D 0.73, the isotropic energy release E_iso is (4.1 =B1 0.4)x10^53 erg, the isotropic peak luminosity L_iso_max is (3.8 =B1 0.7)x10^53 erg/s, and Ep_rest is 894(-168,+312) keV (the initial pulse spectrum).
All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.
GCN Circular #12434
N. P. M. Kuin (MSSL-UCL) and C. J. Saxton (UCL-MSSL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111008A 99 s after the BAT trigger (Saxton et al., GCN Circ. 12423). No optical afterglow consistent with the refined XRT position (Beardmore et al., GCN 12425; see also Levan et al. GCN 12426, Nardini et al. GCN 12428, and Wiersema et al. GCN 12431) is detected in the initial UVOT exposures, consistent with the redshift reported by Levan et al. and Wiersema et al.. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            99          249          147         >21.3
u_FC               311          561          246         >20.5
white               99         1359          373         >21.8
v                  641         1409           97         >19.0
b                  566         1335           78         >19.7
u                  311         1310          304         >20.6
w1                 690         1457           77         >19.2
m2                 666         1433           97         >21.0
w2                 617         1385           97         >19.8
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12436
A. Zauderer, E. Berger (Harvard), and D. Frail (NRAO) report:
"We observed the position of GRB 111008A (GCN 12423 ) with the EVLA beginning 2011 October 10.37 UT (1.4 days after the burst). At 22 GHz, we detect a radio source consistent with the Swift-XRT error circle (GCN 12425) and the candidate optical counterpart (GCN 12429) at a position of
```
RA:   04:01:48.24 (+/- 0.04)
Dec:  -32:42:32.7 (+/- 0.6)
```
Further observations are planned."
GCN Circular #12437
M. Konishi, K. Tateuchi, K. Motohara, T. Tanabe, T. Kamizuka, A. Nakashima, T. Minezaki, and Y. Yoshii (University of Tokyo), S. Komugi (NAOJ/ALMA), S. Manabe (Kobe University), report on behalf of the TAO project team
We report the near-infrared (NIR) imaging observation of GRB111008A (Saxton et al., GCN 12423) using NIR Camera ANIR mounted on the miniTAO 1.0m telescope at the University of Tokyo Atacama Observatory, located on the summit of Co. Chajnantor (5,640m altitude) in the northern Chile. Observations started at 04:36 UT on October 09, approximately 6 hours after the burst.
We detect a point source at the coordinate reported by Levan et al. (GCN 12426) in the JHKs-bands. The preliminary magnitudes are
```
J = 19.79 +/- 0.18,
H = 19.47 +/- 0.19,
Ks = 19.38 +/- 0.17,
```
in AB system.
1309.2940 from 13 Sep 13
M. Sparre et al.: Two high-redshift DLAs towards a z~5 gamma-ray burst
Observations of the afterglows of long gamma-ray bursts (GRBs) allow the study of star-forming galaxies across most of cosmic history. Here we present observations of GRB 111008A from which we can measure abundance patterns, metallicity, dust content and extinction of the GRB host galaxy (z=5.0) as well as a Damped Lyman-alpha Absorber (DLA) galaxy along the line of sight (z=4.6). These systems have column densities of log N =22.30 +/- 0.06 and 21.34 +/- 0.10, respectively. The GRB host galaxy has a metallicity of 2% solar (based on sulfur), and a lower limit of the metallicity for the intervening DLA is 3% (based on silicon). For the intervening absorber we also measure -1.73<[Fe/H]<-1.09, but the true metallicity can be higher, because it is unclear how much the abundances are affected by dust depletion. The presence and variability of fine-structure lines confirms the z=5.0 system as the GRB host. This is the highest redshift where Fe II fine-structure lines have been detected. The afterglow is only mildly reddened with A_V = 0.11 +/- 0.04 mag, and the host galaxy has a dust-to-metals ratio which is consistent with being equal to or lower than typical values in the Local Group.
1312.3544 from 13 Dec 13
Martin Sparre: The Metallicity of High-z GRBs: the Case of GRB 111008A
With optical and near-infrared follow-up observations of gamma-ray bursts (GRBs) it is possible to study the chemical enrichment of galaxies at high redshift. Especially interesting are measurements of the metallicity of GRB host with $z\gtrsim 4.7$, since it has recently been shown that damped Lymann-$\alpha$ absorbers have a rapid decrease in metallicity at this redshift (Rafelski et al. 2013). In this paper measurements of the amount of metals and dust in the host galaxy of GRB 111008A at $z=5.0$ is presented, and it is discussed how observations of more high-$z$ GRB host galaxies can give clues about dust formation mechanisms and the distribution of metals in the early Universe.

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Jochen Greiner, last update: 13-Dec-2013 [Disclaimer]