Gamma-ray Burst 120922A

(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 22 Sep 12 22:31:13 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.756d {+15h 39m 01s} (J2000),
                 234.940d {+15h 39m 46s} (current),
                 234.032d {+15h 36m 08s} (1950)
GRB_DEC:         -20.177d {-20d 10' 36"} (J2000),
                 -20.218d {-20d 13' 03"} (current),
                 -20.015d {-20d 00' 53"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       16249 [cnts]    Image_Peak=310 [image_cnts]
TRIGGER_DUR:     4.096 [sec] 
TRIGGER_INDEX:   298     E_range: 25-100 keV
BKG_INTEN:       143422 [cnts]
BKG_TIME:        80974.32 SOD {22:29:34.32} UT
BKG_DUR:         40 [sec]
GRB_DATE:        16192 TJD;   266 DOY;   12/09/22
GRB_TIME:        81028.65 SOD {22:30:28.65} UT
GRB_PHI:         -30.54 [deg]
GRB_THETA:        44.36 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     7.54 [sigma]
IMAGE_SIGNIF:    7.36 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  -3  +0  +0 -54  +0 
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 21"}
SUN_DIST:         57.07 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.03d {+18h 08m 07s}  -20.61d {-20d 36' 23"}
MOON_DIST:        34.69 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.99, 27.68 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      237.20, -0.66 [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 = 208.85,-20.21 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:32:37 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     370045932
GRB_RA:          308.267d {+20h 33m 04s} (J2000),
                 308.479d {+20h 33m 55s} (current),
                 307.429d {+20h 29m 43s} (1950)
GRB_DEC:         -41.733d {-41d 43' 59"} (J2000),
                 -41.689d {-41d 41' 21"} (current),
                 -41.904d {-41d 54' 14"} (1950)
GRB_ERROR:       21.03 [deg radius, statistical plus systematic]
GRB_INTEN:       115 [cnts/sec]
DATA_SIGNIF:     5.00 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16192 TJD;   266 DOY;   12/09/22
GRB_TIME:        81129.47 SOD {22:32:09.47} UT
GRB_PHI:          40.00 [deg]
GRB_THETA:       150.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.79
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      72%  GRB
2nd_MOST_LIKELY:  14%  SGR_1806n20
DETECTORS:       0,0,1, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 22"}
SUN_DIST:        117.41 [deg]   Sun_angle= -8.5 [hr] (East of Sun)
MOON_POSTN:      272.05d {+18h 08m 11s}  -20.61d {-20d 36' 19"}
MOON_DIST:        37.21 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      359.42,-36.05 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      299.94,-22.19 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 206.53,-11.23 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:32:51 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     370045932
GRB_RA:          230.860d {+15h 23m 26s} (J2000),
                 231.044d {+15h 24m 11s} (current),
                 230.138d {+15h 20m 33s} (1950)
GRB_DEC:         -20.870d {-20d 52' 11"} (J2000),
                 -20.915d {-20d 54' 52"} (current),
                 -20.693d {-20d 41' 33"} (1950)
GRB_ERROR:       15.39 [deg radius, statistical only]
DATA_SIGNIF:     6.80 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16192 TJD;   266 DOY;   12/09/22
GRB_TIME:        81129.47 SOD {22:32:09.47} UT
GRB_PHI:          34.00 [deg]
GRB_THETA:        83.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 22"}
SUN_DIST:         53.73 [deg]   Sun_angle= -3.4 [hr] (East of Sun)
MOON_POSTN:      272.05d {+18h 08m 11s}  -20.61d {-20d 36' 18"}
MOON_DIST:        38.24 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      344.32, 29.53 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      233.83, -2.21 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:33:01 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.7505d {+15h 39m 00.11s} (J2000),
                 234.9349d {+15h 39m 44.37s} (current),
                 234.0271d {+15h 36m 06.51s} (1950)
GRB_DEC:         -20.1839d {-20d 11' 02.0"} (J2000),
                 -20.2247d {-20d 13' 28.9"} (current),
                 -20.0218d {-20d 01' 18.4"} (1950)
GRB_ERROR:       5.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.53e-08 [erg/cm2/sec]
GRB_SIGNIF:      6.55 [sigma]
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81145.07 SOD {22:32:25.07} UT,   116.4 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.21 261.54 243.41
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 23"}
SUN_DIST:         57.07 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.05d {+18h 08m 12s}  -20.61d {-20d 36' 18"}
MOON_DIST:        34.71 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.68 [deg] galactic lon,lat of the burst
ECL_COORDS:      237.20, -0.67 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.50 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:33:17 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.7505d {+15h 39m 00.1s} (J2000),
                 234.9349d {+15h 39m 44.3s} (current),
                 234.0271d {+15h 36m 06.5s} (1950)
GRB_DEC:         -20.1839d {-20d 11' 02.0"} (J2000),
                 -20.2247d {-20d 13' 28.9"} (current),
                 -20.0218d {-20d 01' 18.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       43 [cnts]
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81145.07 SOD {22:32:25.07} UT,   116.4 [sec] since BAT Trigger Time
CENTROID_X:      336.02,  raw= 336  [pixels]
CENTROID_Y:      323.82,  raw= 324  [pixels]
ROLL:            283.72 [deg]
GAIN:            1
MODE:            2, Short Image mode
WAVEFORM:        134
EXPO_TIME:       0.10 [sec]
GRB_POS_XRT_Y:   60.87
GRB_POS_XRT_Z:   76.18
IMAGE_URL:       sw00534394000msxps_rw.img
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 23"}
SUN_DIST:         57.07 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.05d {+18h 08m 13s}  -20.60d {-20d 36' 17"}
MOON_DIST:        34.71 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.68 [deg] galactic lon,lat of the burst
ECL_COORDS:      237.20, -0.67 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:33:10 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.7505d {+15h 39m 00.1s} (J2000),
                 234.9349d {+15h 39m 44.3s} (current),
                 234.0271d {+15h 36m 06.5s} (1950)
GRB_DEC:         -20.1839d {-20d 11' 02.0"} (J2000),
                 -20.2247d {-20d 13' 28.9"} (current),
                 -20.0218d {-20d 01' 18.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       43 [cnts]
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81145.07 SOD {22:32:25.07} UT,   116.4 [sec] since BAT Trigger Time
CENTROID_X:      336.02,  raw= 336  [pixels]
CENTROID_Y:      323.82,  raw= 324  [pixels]
ROLL:            283.72 [deg]
GAIN:            1
MODE:            2, Short Image mode
WAVEFORM:        134
EXPO_TIME:       0.10 [sec]
GRB_POS_XRT_Y:   60.87
GRB_POS_XRT_Z:   76.18
IMAGE_URL:       sw00534394000msxps_rw.img
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 23"}
SUN_DIST:         57.07 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.05d {+18h 08m 12s}  -20.61d {-20d 36' 17"}
MOON_DIST:        34.71 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.68 [deg] galactic lon,lat of the burst
ECL_COORDS:      237.20, -0.67 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:34:04 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.756d {+15h 39m 01s} (J2000),
                 234.940d {+15h 39m 46s} (current),
                 234.032d {+15h 36m 08s} (1950)
GRB_DEC:         -20.177d {-20d 10' 36"} (J2000),
                 -20.218d {-20d 13' 03"} (current),
                 -20.015d {-20d 00' 53"} (1950)
GRB_DATE:        16192 TJD;   266 DOY;   12/09/22
GRB_TIME:        81028.65 SOD {22:30:28.65} UT
TRIGGER_INDEX:   298
GRB_PHI:         -30.54 [deg]
GRB_THETA:        44.36 [deg]
DELTA_TIME:      6.00 [sec]
TRIGGER_DUR:     4.096 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     7.54 [sigma]
IMAGE_SIGNIF:    7.36 [sigma]
LC_URL:          sw00534394000msb.lc
SUN_POSTN:       180.28d {+12h 01m 08s}   -0.12d {-00d 07' 24"}
SUN_DIST:         57.07 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.06d {+18h 08m 14s}  -20.60d {-20d 36' 14"}
MOON_DIST:        34.72 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.99, 27.68 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      237.20, -0.66 [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 = 208.85,-20.21 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:37:50 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.732d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.161d {-20d 09' 39"} (J2000)
POINT_ROLL:      283.722d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81155.28 SOD {22:32:35.28} UT,   126.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.581
N_STARS:         86
X_OFFSET:        283 [pixels]
Y_OFFSET:        523 [pixels]
X_MAX:           1242 [pixels]
Y_MAX:           1482 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    15
SL_URL:          sw00534394000msufc0126.fits
SUN_POSTN:       180.29d {+12h 01m 09s}   -0.12d {-00d 07' 27"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.10d {+18h 08m 24s}  -20.60d {-20d 36' 02"}
MOON_DIST:        34.78 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:38:17 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.732d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.161d {-20d 09' 39"} (J2000)
POINT_ROLL:      283.722d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81155.28 SOD {22:32:35.28} UT,   126.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.581
N_STARS:         86
X_OFFSET:        283 [pixels]
Y_OFFSET:        523 [pixels]
X_MAX:           1242 [pixels]
Y_MAX:           1482 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    15
SL_URL:          sw00534394000msufc0126.fits
SUN_POSTN:       180.29d {+12h 01m 09s}   -0.12d {-00d 07' 28"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.10d {+18h 08m 25s}  -20.60d {-20d 36' 01"}
MOON_DIST:        34.78 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:39:26 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.732d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.161d {-20d 09' 39"} (J2000)
ROLL:            283.722d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81155.28 SOD {22:32:35.28} UT,   126.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     370045964
X_OFFSET:        603 [pixels]
Y_OFFSET:        843 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       763
Y_GRB_POS:       1003
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0136.fits
SUN_POSTN:       180.29d {+12h 01m 09s}   -0.12d {-00d 07' 29"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.12d {+18h 08m 28s}  -20.60d {-20d 35' 57"}
MOON_DIST:        34.79 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:39:44 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.732d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.161d {-20d 09' 39"} (J2000)
ROLL:            283.722d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81155.28 SOD {22:32:35.28} UT,   126.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     370045964
X_OFFSET:        603 [pixels]
Y_OFFSET:        843 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       763
Y_GRB_POS:       1003
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0136.fits
SUN_POSTN:       180.29d {+12h 01m 09s}   -0.13d {-00d 07' 29"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.12d {+18h 08m 29s}  -20.60d {-20d 35' 56"}
MOON_DIST:        34.79 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 #13793
V. N. Yershov (UCL-MSSL), S. D. Barthelmy (GSFC), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL), C. J. Mountford (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 22:30:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120922A (trigger=534394). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 234.756, -20.177 which is
```
   RA(J2000) = 15h 39m 01s
   Dec(J2000) = -20d 10' 36"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multiple-peaked structure with a duration of at least 130 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~102 sec after the trigger.
The XRT began observing the field at 22:32:25.0 UT, 116.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 234.7505, -20.1839 which is equivalent to:
```
   RA(J2000)  = +15h 39m 0.12s
   Dec(J2000) = -20d 11' 02.0"
```
with an uncertainty of 5.6 arcseconds (radius, 90% containment). This location is 31 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 0.1 s image was 2.53e-08 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 126 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 0.15.
Burst Advocate for this burst is V. N. Yershov (vny 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 22 Sep 12 22:43:55 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
POINT_ROLL:      283.723d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81313.45 SOD {22:35:13.45} UT,   284.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        2.279
N_STARS:         56
X_OFFSET:        283 [pixels]
Y_OFFSET:        523 [pixels]
X_MAX:           1242 [pixels]
Y_MAX:           1482 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00534394000msufc0284.fits
SUN_POSTN:       180.29d {+12h 01m 10s}   -0.13d {-00d 07' 33"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.16d {+18h 08m 39s}  -20.60d {-20d 35' 43"}
MOON_DIST:        34.83 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:44:15 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
POINT_ROLL:      283.723d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81313.45 SOD {22:35:13.45} UT,   284.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        2.279
N_STARS:         56
X_OFFSET:        283 [pixels]
Y_OFFSET:        523 [pixels]
X_MAX:           1242 [pixels]
Y_MAX:           1482 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00534394000msufc0284.fits
SUN_POSTN:       180.29d {+12h 01m 10s}   -0.13d {-00d 07' 34"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.17d {+18h 08m 40s}  -20.60d {-20d 35' 42"}
MOON_DIST:        34.84 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:45:18 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
ROLL:            283.723d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81313.45 SOD {22:35:13.45} UT,   284.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     370046123
X_OFFSET:        603 [pixels]
Y_OFFSET:        843 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       763
Y_GRB_POS:       1003
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0294.fits
SUN_POSTN:       180.29d {+12h 01m 10s}   -0.13d {-00d 07' 35"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.18d {+18h 08m 42s}  -20.59d {-20d 35' 38"}
MOON_DIST:        34.85 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:45:35 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
ROLL:            283.723d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81313.45 SOD {22:35:13.45} UT,   284.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     370046123
X_OFFSET:        603 [pixels]
Y_OFFSET:        843 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       763
Y_GRB_POS:       1003
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0294.fits
SUN_POSTN:       180.29d {+12h 01m 10s}   -0.13d {-00d 07' 35"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.18d {+18h 08m 43s}  -20.59d {-20d 35' 37"}
MOON_DIST:        34.85 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.71 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:51:56 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
POINT_ROLL:      283.724d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81893.32 SOD {22:44:53.32} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.447
N_STARS:         190
X_OFFSET:        43 [pixels]
Y_OFFSET:        283 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1722 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    14
SL_URL:          sw00534394000msufc0864.fits
SUN_POSTN:       180.30d {+12h 01m 11s}   -0.13d {-00d 07' 41"}
SUN_DIST:         57.04 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.25d {+18h 08m 59s}  -20.59d {-20d 35' 17"}
MOON_DIST:        34.91 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.70 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:52:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
POINT_ROLL:      283.724d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81893.32 SOD {22:44:53.32} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.447
N_STARS:         190
X_OFFSET:        43 [pixels]
Y_OFFSET:        283 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1722 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    14
SL_URL:          sw00534394000msufc0864.fits
SUN_POSTN:       180.30d {+12h 01m 11s}   -0.13d {-00d 07' 41"}
SUN_DIST:         57.03 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.25d {+18h 09m 00s}  -20.59d {-20d 35' 15"}
MOON_DIST:        34.92 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.70 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:52:56 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     534394,   Seg_Num: 0
GRB_RA:          234.7480d {+15h 39m 00.48s} (J2000),
                 234.9324d {+15h 39m 43.77s} (current),
                 234.0246d {+15h 36m 05.91s} (1950)
GRB_DEC:         -20.1822d {-20d 10' 55.9"} (J2000),
                 -20.2230d {-20d 13' 22.8"} (current),
                 -20.0201d {-20d 01' 12.2"} (1950)
GRB_ERROR:       2.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81608.00 SOD {22:40:08.00} UT,   579.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       180.30d {+12h 01m 11s}   -0.13d {-00d 07' 42"}
SUN_DIST:         57.05 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.26d {+18h 09m 01s}  -20.59d {-20d 35' 13"}
MOON_DIST:        34.91 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.68 [deg] galactic lon,lat of the burst
ECL_COORDS:      237.20, -0.67 [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 0.11% < P(seren) < 0.58%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Sep 12 22:55:30 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
ROLL:            283.724d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81893.32 SOD {22:44:53.32} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     370046703
X_OFFSET:        602 [pixels]
Y_OFFSET:        842 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       762
Y_GRB_POS:       1002
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0874.fits
SUN_POSTN:       180.30d {+12h 01m 12s}   -0.13d {-00d 07' 44"}
SUN_DIST:         57.03 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.28d {+18h 09m 08s}  -20.59d {-20d 35' 05"}
MOON_DIST:        34.95 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.70 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 22 Sep 12 22:55:59 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     534394,   Seg_Num: 0
POINT_RA:        234.733d {+15h 38m 56s} (J2000)
POINT_DEC:       -20.163d {-20d 09' 44"} (J2000)
ROLL:            283.724d
IMG_START_DATE:  16192 TJD;   266 DOY;   12/09/22
IMG_START_TIME:  81893.32 SOD {22:44:53.32} UT,   864.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     370046703
X_OFFSET:        602 [pixels]
Y_OFFSET:        842 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       762
Y_GRB_POS:       1002
BINNING_INDEX:   1
IM_URL:          sw00534394000msuni0874.fits
SUN_POSTN:       180.30d {+12h 01m 12s}   -0.13d {-00d 07' 45"}
SUN_DIST:         57.03 [deg]   Sun_angle= -3.6 [hr] (East of Sun)
MOON_POSTN:      272.29d {+18h 09m 09s}  -20.58d {-20d 35' 04"}
MOON_DIST:        34.95 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      347.98, 27.70 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      237.18, -0.65 [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 #13794
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 120922A, we find an enhanced XRT position of the afterglow: RA, Dec: 234.7483, -20.1821 which is equivalent to:
```
   RA (J2000)  = 15 38 59.60
   Dec (J2000) = -20 10 55.4
```
with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/534394.
Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
GCN Circular #13795
F. Knust (MPE Garching), T. Kruehler (DARK), J. Greiner (MPE) and S. Klose (TLS Tautenburg) report on behalf of the GROND team:
We observed the field of GRB 120922A (Swift trigger 534394; Yershov et al., GCN 13793) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG/ESO telescope at La Silla Observatory (Chile).
Observations started at 23:30 UT on Sep 22, 60 min after the GRB trigger. We detect a bright source within the enhanced Swift/XRT error circle reported by Evans (GCN 13794) at coordinates RA, DEC (J2000) = 15:38:59.64, -20:10:54.2 (+/- 0.3 arcsec) with (AB mag)
r' = 19.5 +/- 0.1,
calibrated against the GROND zeropoint and not corrected for the Galactic foreground reddening of E_(B-V)= 0.15 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular #13799
Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR), Boer M. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report:
We imaged the field of GRB 120922A detected by SWIFT (trigger 534394) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile.
The observations started 56 min after the GRB trigger (starting at twilight). The elevation of the field decreased from 46 degrees above horizon and weather conditions were good.
Co addition of TAROT images from 56 to 85 minutes after the GRB, shows the optical candidate reported by Knust et al. (GCNC 13795) at magnitude R~20 (close to the limiting magnitude of TAROT). Note the source NOMAD1 0698-0330778 (R.A.=234.7496389 Decl=-20.1828917 J2000) R=19.79 few arcsec southeastern from the OT.
This message may be cited.
GCN Circular #13800
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1474 s of XRT Photon Counting mode data and 1 UVOT images for GRB 120922A, 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 = 234.74858, -20.18203 which is equivalent to:
```
RA (J2000): 15h 38m 59.66s
Dec (J2000): -20d 10' 55.3"
```
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 #13803
V.N. Yershov (UCL-MSSL), aN. P. M. Kuin (MSSL-UCL) and A. A. Breeveld (MSSL-UCL), report on behalf of the Swift-UVOT team:
UVOT took a finding chart exposure of 150 seconds with the White filter starting 864 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =  15:38:59.60 = 234.74832
  DEC(J2000) = -20:10:54.3  = -20.18175
```
with a 90%-confidence error radius of about 0.65 arc sec. This position is 2.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.91 with a 1-sigma error of about 0.16. No correction has been made for the expected extinction corresponding to E(B-V) of 0.15.
GCN Circular #13804
A. Melandri (INAF-OAB), D.N. Burrows (PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC) and V.N. Yershov report on behalf of the Swift-XRT team:
We have analysed 9.3 ks of XRT data for GRB 120922A (Yershov et al. GCN Circ. 13793), from 120 s to 19.4 ks after the BAT trigger. The data comprise 484 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 13794).
The light curve can be modelled with a series of power-law decays. The light curve initially rises, with an index alpha=-1.5 (+0.0, -1.3). At T+130 s it breaks to an alpha of 3.09 (+0.09, -0.08). The light curve breaks again at T+243 s to a decay with alpha=3.83 (+0.09, -0.10), before a final break at T+737 s s after which the decay index is 0.85 (+0.04, -0.05).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.33 (+/-0.04). The best-fitting absorption column is 2.15 (+/-0.09) x 10^21 cm^-2, in excess of the Galactic value of 7.7 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.11 (+0.13, -0.12) and a best-fitting absorption column of 1.06 (+0.28, -0.27) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.6 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.06 (+0.28, -0.27) x 10^21 cm^-2
Galactic foreground: 7.7 x 10^20 cm^-2
Excess significance: 1.8 sigma
Photon index:	     2.11 (+0.13, -0.12)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00534394.
This circular is an official product of the Swift-XRT team.
GCN Circular #13806
H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU), V. N. Yershov (UCL-MSSL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+303 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120922A (trigger #534394) (Yershov, et al., GCN Circ. 13793). The BAT ground-calculated position is RA, Dec = 234.758, -20.181 deg, which is
```
   RA(J2000)  =  15h 39m 02.0s 
   Dec(J2000) = -20d 10' 51.8" 
```
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 33%.
The mask-weighted light curve shows low-level emission starting at T-200 sec, possibly sooner before the data capture started, with peaks at ~T_0, ~T+60, & ~T+105 sec, and ending at ~T+205 sec. T90 (15-350 keV) is 173 +- 33 sec (estimated error including systematics).
The time-averaged spectrum from T-22.58 to T+215.73 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.58 +- 0.36, and Epeak of 38.2 +- 0.0 keV (chi squared 54.3 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 6.2 +- 0.7 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+99.21 sec in the 15-150 keV band is 2.0 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 2.09 +- 0.08 (chi squared 61.1 for 57 d.o.f.). 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/534394/BA/
GCN Circular #13808
N. P. M. Kuin (MSSL/UCL) and V.N. Yershov (MSSL/UCL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120922A 127 s after the BAT trigger (Yershov et al., GCN Circ. 13793). A source consistent with the XRT position (Evans et al. GCN Circ. 13800), and the initial optical detection by GROND (Knust et al., GCN Circ. 13795) is detected in the initial UVOT exposures (Yershov et al. GCN Circ. 13803).
The uvot observations show a slow initial rise in brightness peaking around 900s after the trigger. The burst is only detected in the v,b and white filters which is probably due to the high galactic reddening.
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

white              126          276          147        >20.67
white              865         1014          147         19.34 +/- 0.14
v                  615         1239           78         17.94 +/- 0.22
b                  541          733           78        >19.17
b                 1145         2030          119         19.62 +/- 0.36
u                  285          534          250        >19.98
u                  688         1139           40        >18.82
w1                 664        16852         1434        >20.95
m2                 639        11081         1232        >20.96
w2                 590        12900         1424        >21.20
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.15 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #13809
George Younes (MSFC/USRA) reports on behalf of the Fermi GBM Team:
"At 22:32:09.47 UT on 22 September 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120922A (trigger 370045932 / 120922939) which was also detected by the Swift/BAT (Yershov et al. 2012, GCN 13793). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 85 degrees.
The GBM light curve consists of a multiple peaks with a duration (T90) of about 180 s (50-300 keV). The time-averaged spectrum from T0-121 s to T0+6 s is best fit by a Band function with Epeak = 37.7 +/- 3.5 keV, alpha = 1.6 +/- 0.7 , and beta = -2.3 +/- 0.1.
The event fluence (10-1000 keV) in this time interval is (6.5 +/- 0.4)E-06 ergs/cm^2. The 1-sec peak photon flux measured starting from T0-1.8 s in the 10-1000 keV band is 3.4 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #13810
F. Knust (MPE Garching), T. Kruehler (DARK/NBI), S. Klose (TLS Tautenburg) and J. Greiner (MPE Garching) report on behalf of the GROND team:
We report on further analysis of the GROND (Greiner et al. 2008, PASP 120, 405) optical/NIR imaging of the afterglow (Knust et al. GCN 13795, Klotz et al., GCN 13799, Yershov et al., GCN 13803, Kuin et al., GCN 13808) of GRB 120922A (Yershov et al., GCN 13793). Tying our photometric solution to field stars from the SDSS in the optical filters and 2MASS in the NIR, we derive the following AB magnitudes centered at a midtime of 00:01 UTC on September 23 (approx 1.5 hrs after the trigger):
```
g' = 20.53 +/- 0.05
r' = 19.69 +/- 0.04
i' = 19.44 +/- 0.04
z' = 19.28 +/- 0.04 
J = 18.92 +/- 0.06
H = 18.79 +/- 0.07
K = 18.63 +/- 0.10
```
After correcting these magnitudes for the expected Galactic foreground extinction corresponding to a reddening of E_B-V = 0.15 mag (Schlegel et al. 1998), the SED is well fit with a simple power law of spectral index \beta = 0.5 +/- 0.2 and no strong evidence for host-intrinsic reddening. The significant drop in flux in the g'-band suggests a photometric redshift of 3.1 +/- 0.2, consistent with the lack of detection in the bluer UVOT filters (Kuin et al., GCN 13808).

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Jochen Greiner, last update: 24-Sep-2012 [Disclaimer]