Gamma-ray Burst 100807A

(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 07 Aug 10 09:13:32 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.324d {+03h 41m 18s} (J2000),
                  55.578d {+03h 42m 19s} (current),
                  54.132d {+03h 36m 32s} (1950)
GRB_DEC:         +67.679d {+67d 40' 43"} (J2000),
                 +67.712d {+67d 42' 44"} (current),
                 +67.518d {+67d 31' 05"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5118 [cnts]    Image_Peak=198 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   139     E_range: 15-50 keV
BKG_INTEN:       33616 [cnts]
BKG_TIME:        33177.94 SOD {09:12:57.94} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15415 TJD;   219 DOY;   10/08/07
GRB_TIME:        33193.62 SOD {09:13:13.62} UT
GRB_PHI:         -110.12 [deg]
GRB_THETA:        32.98 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.32 [sigma]
IMAGE_SIGNIF:    9.13 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +1  +0  +0  +1 -31  +0 
SUN_POSTN:       137.24d {+09h 08m 57s}  +16.40d {+16d 24' 06"}
SUN_DIST:         71.70 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.25d {+06h 29m 00s}  +23.64d {+23d 38' 30"}
MOON_DIST:        50.91 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.93 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       71.73, 46.43 [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 = 242.45,18.61 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:15:02 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.2943d {+03h 41m 10.63s} (J2000),
                  55.5485d {+03h 42m 11.63s} (current),
                  54.1028d {+03h 36m 24.67s} (1950)
GRB_DEC:         +67.6713d {+67d 40' 16.6"} (J2000),
                 +67.7048d {+67d 42' 17.2"} (current),
                 +67.5104d {+67d 30' 37.4"} (1950)
GRB_ERROR:       5.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       9.12e-10 [erg/cm2/sec]
GRB_SIGNIF:      6.08 [sigma]
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33274.43 SOD {09:14:34.43} UT,   80.8 [sec] since BAT Trigger Time
TAM[0-3]:        327.63 237.23 261.42 243.71
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       137.24d {+09h 08m 57s}  +16.40d {+16d 24' 05"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.27d {+06h 29m 04s}  +23.64d {+23d 38' 22"}
MOON_DIST:        50.92 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.92 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.71, 46.42 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.81 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:15:13 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.2943d {+03h 41m 10.6s} (J2000),
                  55.5485d {+03h 42m 11.6s} (current),
                  54.1028d {+03h 36m 24.6s} (1950)
GRB_DEC:         +67.6713d {+67d 40' 16.6"} (J2000),
                 +67.7048d {+67d 42' 17.2"} (current),
                 +67.5104d {+67d 30' 37.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       37 [cnts]
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33274.43 SOD {09:14:34.43} UT,   80.8 [sec] since BAT Trigger Time
CENTROID_X:      303.63,  raw= 304  [pixels]
CENTROID_Y:      285.50,  raw= 286  [pixels]
ROLL:            91.04 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -29.45
GRB_POS_XRT_Z:   3.14
IMAGE_URL:       sw00431128000msxps_rw.img
SUN_POSTN:       137.24d {+09h 08m 57s}  +16.40d {+16d 24' 05"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.27d {+06h 29m 05s}  +23.64d {+23d 38' 21"}
MOON_DIST:        50.92 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.92 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.71, 46.42 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:15:23 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.2943d {+03h 41m 10.6s} (J2000),
                  55.5485d {+03h 42m 11.6s} (current),
                  54.1028d {+03h 36m 24.6s} (1950)
GRB_DEC:         +67.6713d {+67d 40' 16.6"} (J2000),
                 +67.7048d {+67d 42' 17.2"} (current),
                 +67.5104d {+67d 30' 37.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       37 [cnts]
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33274.43 SOD {09:14:34.43} UT,   80.8 [sec] since BAT Trigger Time
CENTROID_X:      303.63,  raw= 304  [pixels]
CENTROID_Y:      285.50,  raw= 286  [pixels]
ROLL:            91.04 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -29.45
GRB_POS_XRT_Z:   3.14
IMAGE_URL:       sw00431128000msxps_rw.img
SUN_POSTN:       137.24d {+09h 08m 57s}  +16.40d {+16d 24' 05"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.27d {+06h 29m 05s}  +23.64d {+23d 38' 20"}
MOON_DIST:        50.92 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.92 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.71, 46.42 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:16:51 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.324d {+03h 41m 18s} (J2000),
                  55.578d {+03h 42m 19s} (current),
                  54.132d {+03h 36m 32s} (1950)
GRB_DEC:         +67.679d {+67d 40' 43"} (J2000),
                 +67.712d {+67d 42' 44"} (current),
                 +67.518d {+67d 31' 05"} (1950)
GRB_DATE:        15415 TJD;   219 DOY;   10/08/07
GRB_TIME:        33193.62 SOD {09:13:13.62} UT
TRIGGER_INDEX:   139
GRB_PHI:         -110.12 [deg]
GRB_THETA:        32.98 [deg]
DELTA_TIME:      32.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.32 [sigma]
IMAGE_SIGNIF:    9.13 [sigma]
LC_URL:          sw00431128000msb.lc
SUN_POSTN:       137.24d {+09h 08m 57s}  +16.40d {+16d 24' 04"}
SUN_DIST:         71.70 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.29d {+06h 29m 09s}  +23.64d {+23d 38' 13"}
MOON_DIST:        50.92 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.93 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       71.73, 46.43 [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 = 242.45,18.61 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:17:47 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.299d {+03h 41m 12s} (J2000)
POINT_DEC:       +67.680d {+67d 40' 48"} (J2000)
POINT_ROLL:      91.038d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33284.17 SOD {09:14:44.17} UT,   90.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.289
N_STARS:         84
X_OFFSET:        552 [pixels]
Y_OFFSET:        512 [pixels]
X_MAX:           1511 [pixels]
Y_MAX:           1471 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00431128000msufc0090.fits
SUN_POSTN:       137.24d {+09h 08m 58s}  +16.40d {+16d 24' 03"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.30d {+06h 29m 11s}  +23.64d {+23d 38' 08"}
MOON_DIST:        50.94 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.72, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:17:47 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.299d {+03h 41m 12s} (J2000)
POINT_DEC:       +67.680d {+67d 40' 48"} (J2000)
POINT_ROLL:      91.038d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33284.17 SOD {09:14:44.17} UT,   90.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.289
N_STARS:         84
X_OFFSET:        552 [pixels]
Y_OFFSET:        512 [pixels]
X_MAX:           1511 [pixels]
Y_MAX:           1471 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00431128000msufc0090.fits
SUN_POSTN:       137.24d {+09h 08m 58s}  +16.40d {+16d 24' 03"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.30d {+06h 29m 11s}  +23.64d {+23d 38' 08"}
MOON_DIST:        50.94 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.72, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:18:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.299d {+03h 41m 12s} (J2000)
POINT_DEC:       +67.680d {+67d 40' 48"} (J2000)
POINT_ROLL:      91.038d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33284.17 SOD {09:14:44.17} UT,   90.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.289
N_STARS:         84
X_OFFSET:        552 [pixels]
Y_OFFSET:        512 [pixels]
X_MAX:           1511 [pixels]
Y_MAX:           1471 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00431128000msufc0090.fits
SUN_POSTN:       137.24d {+09h 08m 58s}  +16.40d {+16d 24' 03"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.30d {+06h 29m 12s}  +23.64d {+23d 38' 07"}
MOON_DIST:        50.94 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.72, 46.43 [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 07 Aug 10 09:19:16 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.299d {+03h 41m 12s} (J2000)
POINT_DEC:       +67.680d {+67d 40' 48"} (J2000)
ROLL:            91.038d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33284.17 SOD {09:14:44.17} UT,   90.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     302865290
X_OFFSET:        831 [pixels]
Y_OFFSET:        919 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       991
Y_GRB_POS:       1079
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0097.fits
SUN_POSTN:       137.24d {+09h 08m 58s}  +16.40d {+16d 24' 02"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.31d {+06h 29m 15s}  +23.63d {+23d 38' 01"}
MOON_DIST:        50.94 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.72, 46.43 [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 07 Aug 10 09:19:27 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.299d {+03h 41m 12s} (J2000)
POINT_DEC:       +67.680d {+67d 40' 48"} (J2000)
ROLL:            91.038d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33284.17 SOD {09:14:44.17} UT,   90.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     302865290
X_OFFSET:        831 [pixels]
Y_OFFSET:        919 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       991
Y_GRB_POS:       1079
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0097.fits
SUN_POSTN:       137.24d {+09h 08m 58s}  +16.40d {+16d 24' 02"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.31d {+06h 29m 16s}  +23.63d {+23d 37' 60"}
MOON_DIST:        50.94 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.72, 46.43 [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 #11067
D. Grupe (PSU), W. H. Baumgartner (GSFC/UMBC), J. M. Gelbord (PSU), C. Gronwall (PSU), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA) and D. M. Palmer (LANL) report on behalf of the Swift Team:
At 09:13:13 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 100807A (trigger=431128). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 55.324, +67.679 which is
```
   RA(J2000) = 03h 41m 18s
   Dec(J2000) = +67d 40' 43"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 10 sec. The peak count rate was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 09:14:34.4 UT, 80.8 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 55.30004, 67.67171 which is equivalent to:
```
   RA(J2000)  = 03h 41m 12.01s
   Dec(J2000) = +67d 40' 18.2"
```
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This location is 41 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (3.31e+21 cm^-2, Kalberla et al. 2005), with an excess column of 3.8 (+4.16/-3.25) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 9.12e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 90 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 0.81.
Burst Advocate for this burst is D. Grupe (grupe 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:     Sat 07 Aug 10 09:25:32 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33497.31 SOD {09:18:17.31} UT,   303.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.638
N_STARS:         17
X_OFFSET:        511 [pixels]
Y_OFFSET:        599 [pixels]
X_MAX:           1470 [pixels]
Y_MAX:           1558 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00431128000msufc0303.fits
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 58"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.38d {+06h 29m 31s}  +23.62d {+23d 37' 29"}
MOON_DIST:        50.97 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:25:54 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33497.31 SOD {09:18:17.31} UT,   303.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.638
N_STARS:         17
X_OFFSET:        511 [pixels]
Y_OFFSET:        599 [pixels]
X_MAX:           1470 [pixels]
Y_MAX:           1558 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00431128000msufc0303.fits
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 58"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.38d {+06h 29m 32s}  +23.62d {+23d 37' 28"}
MOON_DIST:        50.97 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 07 Aug 10 09:25:32 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33497.31 SOD {09:18:17.31} UT,   303.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.638
N_STARS:         17
X_OFFSET:        511 [pixels]
Y_OFFSET:        599 [pixels]
X_MAX:           1470 [pixels]
Y_MAX:           1558 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00431128000msufc0303.fits
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 58"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.38d {+06h 29m 31s}  +23.62d {+23d 37' 29"}
MOON_DIST:        50.97 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:27:04 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
ROLL:            91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33497.31 SOD {09:18:17.31} UT,   303.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     302865503
X_OFFSET:        831 [pixels]
Y_OFFSET:        919 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       991
Y_GRB_POS:       1079
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0310.fits
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 57"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.40d {+06h 29m 35s}  +23.62d {+23d 37' 22"}
MOON_DIST:        50.98 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 07 Aug 10 09:26:57 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
ROLL:            91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33497.31 SOD {09:18:17.31} UT,   303.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     302865503
X_OFFSET:        831 [pixels]
Y_OFFSET:        919 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       991
Y_GRB_POS:       1079
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0310.fits
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 57"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.40d {+06h 29m 35s}  +23.62d {+23d 37' 22"}
MOON_DIST:        50.98 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 07 Aug 10 09:26:00 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     431128,   Seg_Num: 0
GRB_RA:           55.3014d {+03h 41m 12.33s} (J2000),
                  55.5556d {+03h 42m 13.33s} (current),
                  54.1098d {+03h 36m 26.35s} (1950)
GRB_DEC:         +67.6718d {+67d 40' 18.4"} (J2000),
                 +67.7053d {+67d 42' 19.0"} (current),
                 +67.5109d {+67d 30' 39.3"} (1950)
GRB_ERROR:       2.5 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  33322.00 SOD {09:15:22.00} UT,   128.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       137.25d {+09h 08m 59s}  +16.40d {+16d 23' 58"}
SUN_DIST:         71.71 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.39d {+06h 29m 33s}  +23.62d {+23d 37' 27"}
MOON_DIST:        50.97 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.02,  9.92 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.72, 46.42 [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 07 Aug 10 09:30:48 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  34054.79 SOD {09:27:34.79} UT,   861.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.474
N_STARS:         190
X_OFFSET:        271 [pixels]
Y_OFFSET:        359 [pixels]
X_MAX:           1710 [pixels]
Y_MAX:           1798 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00431128000msufc0861.fits
SUN_POSTN:       137.25d {+09h 09m 00s}  +16.40d {+16d 23' 54"}
SUN_DIST:         71.72 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.44d {+06h 29m 45s}  +23.62d {+23d 37' 03"}
MOON_DIST:        51.00 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:30:48 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  34054.79 SOD {09:27:34.79} UT,   861.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.474
N_STARS:         190
X_OFFSET:        271 [pixels]
Y_OFFSET:        359 [pixels]
X_MAX:           1710 [pixels]
Y_MAX:           1798 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00431128000msufc0861.fits
SUN_POSTN:       137.25d {+09h 09m 00s}  +16.40d {+16d 23' 54"}
SUN_DIST:         71.72 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.44d {+06h 29m 45s}  +23.62d {+23d 37' 03"}
MOON_DIST:        51.00 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 07 Aug 10 09:31:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
POINT_ROLL:      91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  34054.79 SOD {09:27:34.79} UT,   861.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.474
N_STARS:         190
X_OFFSET:        271 [pixels]
Y_OFFSET:        359 [pixels]
X_MAX:           1710 [pixels]
Y_MAX:           1798 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00431128000msufc0861.fits
SUN_POSTN:       137.25d {+09h 09m 00s}  +16.40d {+16d 23' 54"}
SUN_DIST:         71.72 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.44d {+06h 29m 46s}  +23.62d {+23d 37' 01"}
MOON_DIST:        51.00 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 07 Aug 10 09:32:11 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
ROLL:            91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  34054.79 SOD {09:27:34.79} UT,   861.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     302866060
X_OFFSET:        830 [pixels]
Y_OFFSET:        918 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       990
Y_GRB_POS:       1078
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0868.fits
SUN_POSTN:       137.25d {+09h 09m 00s}  +16.40d {+16d 23' 53"}
SUN_DIST:         71.72 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.45d {+06h 29m 49s}  +23.62d {+23d 36' 56"}
MOON_DIST:        51.00 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 07 Aug 10 09:32:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     431128,   Seg_Num: 0
POINT_RA:         55.291d {+03h 41m 10s} (J2000)
POINT_DEC:       +67.679d {+67d 40' 44"} (J2000)
ROLL:            91.034d
IMG_START_DATE:  15415 TJD;   219 DOY;   10/08/07
IMG_START_TIME:  34054.79 SOD {09:27:34.79} UT,   861.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     302866060
X_OFFSET:        830 [pixels]
Y_OFFSET:        918 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       990
Y_GRB_POS:       1078
BINNING_INDEX:   1
IM_URL:          sw00431128000msuni0868.fits
SUN_POSTN:       137.25d {+09h 09m 00s}  +16.40d {+16d 23' 53"}
SUN_DIST:         71.72 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:       97.46d {+06h 29m 49s}  +23.62d {+23d 36' 55"}
MOON_DIST:        51.00 [deg]
MOON_ILLUM:      11 [%]
GAL_COORDS:      138.01,  9.92 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.71, 46.43 [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 #11068
GRB 100807A: ROTSE-III Optical Limits
W. Rujopakarn (Steward), H. Flewelling (IfA/Hawaii), B. E. Schaefer (Louisiana State), W. Zheng (U Mich), and S. B. Pandey (U Mich), report on behalf of the ROTSE collaboration:
ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 100807A (Swift trigger 431128; Grupe et al., GCN 11067), producing images beginning 5.2 s after the GCN notice time. An automated response took the first image at 09:13:35.2 UT, 21.6 s after the burst, and during the gamma-ray emission, under fair conditions. We took 10 5-sec and 10 20-sec exposures. These unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on going.
Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma Swift/BAT error circle or the XRT error circle, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 15.9-17.2; we set the following specific limits.
```
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
09:13:35.2 09:13:40.2 5 16.2 21.6 N
09:13:35.2 09:14:42.2 67 16.7 21.6 Y
09:14:55.2 09:19:37.9 282 18.1 101.6 Y
```
GCN Circular #11069
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), N. Gehrels (GSFC), D. Grupe (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-61 to T+233 sec from recent telemetry downlinks, we report further analysis of BAT GRB 100807A (trigger #431128) (Grupe, et al., GCN Circ. 11067). The BAT ground-calculated position is RA, Dec = 55.283, 67.665 deg, which is
```
   RA(J2000)  =  03h 41m 07.9s 
   Dec(J2000) = +67d 39' 54.2" 
```
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 37%.
The mask-weighted light curve a single peak starting around T-20 sec, peaking at ~T+0, and ending around T+20 sec. T90 (15-350 keV) is 7.9 +- 1.6 sec (estimated error including systematics).
The time-averaged spectrum from T-6.1 to T+3.1 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.32 +- 0.23. The fluence in the 15-150 keV band is 3.4 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.35 sec in the 15-150 keV band is 1.8 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/431128/BA/
GCN Circular #11070
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 960 s of XRT Photon Counting mode data and 1 UVOT images for GRB 100807A, 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 = 55.30042, +67.67158 which is equivalent to:
```
RA (J2000): 03h 41m 12.10s
Dec (J2000): +67d 40' 17.7"
```
with an uncertainty of 1.9 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 #11072
C. A. Swenson and D. Grupe (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 100807A 91 s after the BAT trigger (Grupe et al., GCN Circ. 11067). No optical afterglow consistent with the enhanced XRT position (Osborne et al., GCN Circ. 11070) is detected in the initial UVOT exposures. 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            91          240          147         >20.9
u_FC               304          553          246         >20.4
white               91         5947          530         >21.8
v                  634         6358          255         >19.6
b                  559         7063          319         >21.1
u                  304         6973          659         >21.1
w1                 683         6768          413         >20.8
m2                6363         6563          197         >20.7
w2                 609         6153          255         >20.8
```
The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.81 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #11073
S. B. Cenko (UC Berkeley) reports on behalf of a larger collaboration:
We have imaged the field of GRB 100807A (Grupe et al., GCN 11067) with the automated Palomar 60 inch telescope. Observations were obtained in the Sloan r', i', and z' filters beginning at 9:16 UT on 7 August (~ 3 min after the Swift trigger).
At the edge of the enhanced XRT position (Osborne et al., GCN 11070), we detect a fading point source with coordinates (J2000.0):
RA: 03:41:12.43 Dec: +67:40:17.4
Using several nearby objects in the USNO-B1 catalog for reference, we report the following photometry for this object:
```
UT (mid-point)	t_burst (min)	Filter		Magnitude
---------------------------------------------------------------
09:16:55	3.7		R		20.47 +/- 0.17
09:18:21	5.1		I		19.80 +/- 0.14
09:47:07	33.9		R		21.57 +/- 0.20
09:49:58	36.8		I		20.96 +/- 0.20
```
The above magnitudes have not been corrected for the large Galactic extinction along the line of sight.
The fading behavior confirms this source is the optical afterglow of GRB 100807A.
GCN Circular #11074
D. Grupe (PSU) reports on behalf of the Swift-XRT team:
We have analyzed 9.7 ks of XRT data for GRB 100807A (Grupe et al. GCN Circ. 11067), from 125 s to 24882 s after the BAT trigger. The data comprise 36 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The light curve can be modeled with a broken power-law model. After an initial flare the light curve decays with a slope of 6.4+0.6-1.9. The light curve breaks at 173+/-10s followed by a flatter decay slope of 0.82+/-0.08.
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.12 (+/-0.22). The best-fitting absorption column is consistent with the Galactic value of 3.3 x 10^21 cm^-2 (Kalberla et al. 2005). A fit to the pc mode data is also consistent with the Galactic absorption column density, but the spectrum is slightly flatter with a photon index of 1.79+/-0.37. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from the WT spectrum is 4.38 x 10^-11 (7.54 x 10^-11) erg cm^-2 count^-1.
If the light curve continues to decay with a power-law decay index of 0.8, the count rate at T+48 hours will be in the order of 1.3 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.7 x 10^-14 (9.8 x 10^-14) erg cm^-2 s^-1. Note that we are currently in the plateau phase which is followed by a steeper decay slope.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00431128.
This circular is an official product of the Swift-XRT team.
GCN Circular #11075
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 100807A (Grupe et al., GCN 11067) 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 2010-08-07 13:29:46 UT (~4.3 h after the burst). We did not find any new point source within the enhanced XRT error circle (Osborne et al., GCNC 11070) in all the three bands. We could not detect the previously reported afterglow (Cenko, GCN 11073).
Three sigma upper limits of the OT are listed below. We used GSC 2.3 catalog for flux calibration.
```
T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.21418    14:21:39  4620.0     >20.1  >19.7  >19.1
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #11078
V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 100807A (Grupe et al., GCN 11067) with Shajn telescope of CrAO in filter R between (UT) Aug. 07 22:58:14 -- Aug. 08 01:17:44 under descending seeing with mean value of ~ 2.1". We do not detect the afterglow (Cenko, GCN 11073). The extended object ~ 8" was detected in coordinates (J2000) center RA: 03 41 12.92 Dec: +67 40 19.4. The position of optical afterglow (Cenko, GCN 11073) is in the edge of the extended object.
The photometry is based on USNO-B1.0 star 1576-0084708 (J2000) RA= 03 41 11.50 Dec= +67 39 58.1 (assuming R=16.37):
```
T0+      Filter,   Exposure, Ext. Object mag.           Upper Limit
(mid, d)              (s)

0.6214  R       97x60       23.0 +/- 0.2                    23.8
```
With upper limit of R=23.8 we confirm the fading nature of afterglow of GRB 100807A (Grupe et al., GCN 11067). The extended object might be a host galaxy of GRB 100807A.
The combined images can be found http://grb.rssi.ru/GRB100807A/GRB100807a_100807_R_ZTSh.gif
GCN Circular #11080
R. Chary and J. Davies (Caltech) report:
We have imaged the field of GRB 100807A (Grupe et al., GCN 11067) with the WIRC instrument on the Palomar 200 inch telescope in the J and H bands beginning at 9:47 UT on 7 August (~ 35 mins after the Swift trigger). The fading transient reported in Cenko et al. (GCN 11073) is clearly detected. Using 2MASS stars for relative photometry, we measure the following photometry for the object:
```
UT (mid-point)  t_burst (min)   Filter          Magnitude
---------------------------------------------------------------
09:55           41              J               19.76 +/- 0.1
10:10           56              H               19.05 +/- 0.1
12:16           183             J               21.10 +/- 0.2
```
The red colors of the source compared to the optical photometry can be attributed to the A_V=2.5 mag of Galactic extinction in this region.
A nearby object 3" to the SE is also quite red with H=18.75+/-0.1 and J-H=1.5 mag and could potentially be the host galaxy.
All magnitudes are in the Vega system.
GCN Report 295.1
GCN_Report 295.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_295_1.pdf by D. Grupe at PSU titled: "Final report on Swift Observations of GRB 100807A"

GCN Circular #11147
J. Kelemen on behalf of the GRB OT observing program at the Konkoly Observatory.

On 08 august 2010 21:29:00 UT (130547 s after the burst) we observed the field 
of GRB 100807A detected by Swift (trigger=431128; Grupe et al., GCN 11067) 
with a 60/90 cm  Schmidt telescope located at the Mountain Station of the 
Konkoly Observatory using R filter. The total exposure of the coadded CCD 
images were 1800 s. We examined the position reported Cenko et al., GCN 11073. 
No fading object brighter than 21.6 +/- 0.2 was detected. 


Time      Mag     Error.      Flag.
[s]       [R]    [1-sigma]  
-------------------------------------
130547   21.6      0.2      Upper Limit
-------------------------------------

The above magnitudes have not been corrected for the Galactic extinction.

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Jochen Greiner, last update: 07-Aug-2010 [Disclaimer]