Gamma-ray Burst 080916

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:45:40 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     324895,   Seg_Num: 0
GRB_RA:          336.302d {+22h 25m 12s} (J2000),
                 336.443d {+22h 25m 46s} (current),
                 335.485d {+22h 21m 56s} (1950)
GRB_DEC:         -57.022d {-57d 01' 17"} (J2000),
                 -56.977d {-56d 58' 38"} (current),
                 -57.276d {-57d 16' 32"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       8314 [cnts]    Image_Peak=860 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 50-350 keV
BKG_INTEN:       32750 [cnts]
BKG_TIME:        35108.89 SOD {09:45:08.89} UT
BKG_DUR:         8 [sec]
GRB_DATE:        14725 TJD;   260 DOY;   08/09/16
GRB_TIME:        35120.61 SOD {09:45:20.61} UT
GRB_PHI:         129.08 [deg]
GRB_THETA:        18.02 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     59.92 [sigma]
IMAGE_SIGNIF:    20.32 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +3 +18  +0  +0 +55  +1 
SUN_POSTN:       174.40d {+11h 37m 35s}   +2.42d {+02d 25' 26"}
SUN_DIST:        123.60 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.87d {+00h 19m 29s}   +6.27d {+06d 16' 03"}
MOON_DIST:        67.37 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.50 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      313.00,-43.05 [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 = 134.28,-1.85 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:47:19 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.284d {+22h 25m 08s} (J2000)
POINT_DEC:       -57.027d {-57d 01' 37"} (J2000)
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35190.82 SOD {09:46:30.82} UT,   70.2 [sec] since BAT Trigger Time
COUNTS:          252    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        4    Max_iter_allowed= 4
ERROR_CODE:      2
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        Algorithm did not converge; too many iterations.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:48:48 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.283d {+22h 25m 08s} (J2000)
POINT_DEC:       -57.027d {-57d 01' 38"} (J2000)
POINT_ROLL:      201.843d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35196.58 SOD {09:46:36.58} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.241
N_STARS:         55
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0075.fits
SUN_POSTN:       174.40d {+11h 37m 35s}   +2.42d {+02d 25' 23"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.90d {+00h 19m 36s}   +6.28d {+06d 16' 53"}
MOON_DIST:        67.40 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:49:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.283d {+22h 25m 08s} (J2000)
POINT_DEC:       -57.027d {-57d 01' 38"} (J2000)
POINT_ROLL:      201.843d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35196.58 SOD {09:46:36.58} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.241
N_STARS:         55
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0075.fits
SUN_POSTN:       174.40d {+11h 37m 35s}   +2.42d {+02d 25' 23"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.91d {+00h 19m 37s}   +6.28d {+06d 17' 04"}
MOON_DIST:        67.40 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 09:50:22 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     324895,   Seg_Num: 0
GRB_RA:          336.302d {+22h 25m 12s} (J2000),
                 336.443d {+22h 25m 46s} (current),
                 335.485d {+22h 21m 56s} (1950)
GRB_DEC:         -57.022d {-57d 01' 17"} (J2000),
                 -56.977d {-56d 58' 38"} (current),
                 -57.276d {-57d 16' 32"} (1950)
GRB_DATE:        14725 TJD;   260 DOY;   08/09/16
GRB_TIME:        35120.61 SOD {09:45:20.61} UT
TRIGGER_INDEX:   146
GRB_PHI:         129.08 [deg]
GRB_THETA:        18.02 [deg]
DELTA_TIME:      -50.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     59.92 [sigma]
IMAGE_SIGNIF:    20.32 [sigma]
LC_URL:          sw00324895000msb.lc
SUN_POSTN:       174.40d {+11h 37m 36s}   +2.42d {+02d 25' 22"}
SUN_DIST:        123.60 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.91d {+00h 19m 39s}   +6.29d {+06d 17' 17"}
MOON_DIST:        67.40 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.50 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      313.00,-43.05 [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 = 134.28,-1.85 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:50:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.283d {+22h 25m 08s} (J2000)
POINT_DEC:       -57.027d {-57d 01' 38"} (J2000)
ROLL:            201.843d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35196.58 SOD {09:46:36.58} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     243251199
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0075.fits
SUN_POSTN:       174.40d {+11h 37m 36s}   +2.42d {+02d 25' 22"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.91d {+00h 19m 40s}   +6.29d {+06d 17' 20"}
MOON_DIST:        67.41 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:50:09 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.283d {+22h 25m 08s} (J2000)
POINT_DEC:       -57.027d {-57d 01' 38"} (J2000)
ROLL:            201.843d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35196.58 SOD {09:46:36.58} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     243251199
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0075.fits
SUN_POSTN:       174.40d {+11h 37m 36s}   +2.42d {+02d 25' 22"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.91d {+00h 19m 39s}   +6.29d {+06d 17' 14"}
MOON_DIST:        67.41 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 09:58:05 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35302.54 SOD {09:48:22.54} UT,   181.9 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.187
N_STARS:         101
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0181.fits
SUN_POSTN:       174.40d {+11h 37m 37s}   +2.42d {+02d 25' 14"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.98d {+00h 19m 55s}   +6.32d {+06d 19' 19"}
MOON_DIST:        67.46 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 09:58:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35302.54 SOD {09:48:22.54} UT,   181.9 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.187
N_STARS:         101
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0181.fits
SUN_POSTN:       174.40d {+11h 37m 37s}   +2.42d {+02d 25' 14"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.98d {+00h 19m 56s}   +6.32d {+06d 19' 26"}
MOON_DIST:        67.46 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 09:59:18 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35302.54 SOD {09:48:22.54} UT,   181.9 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     243251305
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0181.fits
SUN_POSTN:       174.40d {+11h 37m 37s}   +2.42d {+02d 25' 13"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.99d {+00h 19m 58s}   +6.33d {+06d 19' 38"}
MOON_DIST:        67.47 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 09:59:39 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35302.54 SOD {09:48:22.54} UT,   181.9 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     243251305
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0181.fits
SUN_POSTN:       174.40d {+11h 37m 37s}   +2.42d {+02d 25' 13"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        4.99d {+00h 19m 59s}   +6.33d {+06d 19' 43"}
MOON_DIST:        67.47 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:03:37 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35992.54 SOD {09:59:52.54} UT,   871.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.246
N_STARS:         54
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0871.fits
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 09"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.03d {+00h 20m 07s}   +6.35d {+06d 20' 45"}
MOON_DIST:        67.50 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:04:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35992.54 SOD {09:59:52.54} UT,   871.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.246
N_STARS:         54
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0871.fits
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 09"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.03d {+00h 20m 08s}   +6.35d {+06d 20' 53"}
MOON_DIST:        67.50 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 10:04:49 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35992.54 SOD {09:59:52.54} UT,   871.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     243251995
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0871.fits
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 08"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.04d {+00h 20m 09s}   +6.35d {+06d 21' 04"}
MOON_DIST:        67.50 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 10:04:28 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     324895,   Seg_Num: 0
GRB_RA:          336.2769d {+22h 25m 06.4s} (J2000),
                 336.4184d {+22h 25m 40.4s} (current),
                 335.4601d {+22h 21m 50.4s} (1950)
GRB_DEC:         -57.0228d {-57d 01' 22.0"} (J2000),
                 -56.9784d {-56d 58' 42.1"} (current),
                 -57.2769d {-57d 16' 36.7"} (1950)
GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35372.00 SOD {09:49:32.00} UT,   251.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 08"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.04d {+00h 20m 09s}   +6.35d {+06d 20' 59"}
MOON_DIST:        67.50 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.59,-50.49 [deg] galactic lon,lat of the burst
ECL_COORDS:      312.99,-43.04 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
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

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:05:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35992.54 SOD {09:59:52.54} UT,   871.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     243251995
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0871.fits
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 07"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.04d {+00h 20m 10s}   +6.35d {+06d 21' 11"}
MOON_DIST:        67.51 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:05:01 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     324895,   Seg_Num: 0
GRB_RA:          336.2758d {+22h 25m 06.19s} (J2000),
                 336.4173d {+22h 25m 40.16s} (current),
                 335.4590d {+22h 21m 50.16s} (1950)
GRB_DEC:         -57.0230d {-57d 01' 22.8"} (J2000),
                 -56.9786d {-56d 58' 42.9"} (current),
                 -57.2771d {-57d 16' 37.4"} (1950)
GRB_ERROR:       0.4 [arcsec radius, statistical only]
GRB_MAG:         18.29 +/- 0.50 [mag]
FILTER:          10, White
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  35198.00 SOD {09:46:38.00} UT,   77.4 [sec] since BAT Trigger Time
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 08"}
SUN_DIST:        123.59 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.04d {+00h 20m 10s}   +6.35d {+06d 21' 07"}
MOON_DIST:        67.50 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.59,-50.49 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      312.99,-43.04 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:09:21 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  36098.90 SOD {10:01:38.90} UT,   978.3 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.197
N_STARS:         101
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0978.fits
SUN_POSTN:       174.41d {+11h 37m 38s}   +2.42d {+02d 25' 04"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.08d {+00h 20m 19s}   +6.37d {+06d 22' 15"}
MOON_DIST:        67.53 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 16 Sep 08 10:09:52 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
POINT_ROLL:      201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  36098.90 SOD {10:01:38.90} UT,   978.3 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.197
N_STARS:         101
X_OFFSET:        379 [pixels]
Y_OFFSET:        541 [pixels]
X_MAX:           1338 [pixels]
Y_MAX:           1500 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00324895000msufc0978.fits
SUN_POSTN:       174.41d {+11h 37m 39s}   +2.42d {+02d 25' 03"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.08d {+00h 20m 20s}   +6.37d {+06d 22' 24"}
MOON_DIST:        67.54 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 10:10:32 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  36098.90 SOD {10:01:38.90} UT,   978.3 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     243252102
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0978.fits
SUN_POSTN:       174.41d {+11h 37m 39s}   +2.42d {+02d 25' 02"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.09d {+00h 20m 21s}   +6.38d {+06d 22' 34"}
MOON_DIST:        67.54 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:     Tue 16 Sep 08 10:11:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     324895,   Seg_Num: 0
POINT_RA:        336.280d {+22h 25m 07s} (J2000)
POINT_DEC:       -57.029d {-57d 01' 43"} (J2000)
ROLL:            201.846d
IMG_START_DATE:  14725 TJD;   260 DOY;   08/09/16
IMG_START_TIME:  36098.90 SOD {10:01:38.90} UT,   978.3 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     243252102
X_OFFSET:        698 [pixels]
Y_OFFSET:        860 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       858
Y_GRB_POS:       1020
BINNING_INDEX:   1
IM_URL:          sw00324895000msuni0978.fits
SUN_POSTN:       174.41d {+11h 37m 39s}   +2.42d {+02d 25' 02"}
SUN_DIST:        123.58 [deg]   Sun_angle= -10.8 [hr] (East of Sun)
MOON_POSTN:        5.09d {+00h 20m 22s}   +6.38d {+06d 22' 41"}
MOON_DIST:        67.55 [deg]
MOON_ILLUM:      99 [%]
GAL_COORDS:      333.58,-50.49 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      312.99,-43.05 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #8237
H. Ziaeepour (UCL-MSSL), L. Vetere (PSU), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), S. Campana (INAF-OAB), P. A. Evans (U Leicester), C. Gronwall (PSU), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (MSSL), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB), S. R. Oates (UCL-MSSL), K. L. Page (U Leicester), D. M. Palmer (LANL), B. Preger (ASDC), P. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 09:45:20 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080916 (trigger=324895). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 336.302, -57.022 which is
```
   RA(J2000) = 22h 25m 12s
   Dec(J2000) = -57d 01' 17"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a double-peaked structure with a duration of about 60 sec. The peak count rate was ~5000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 09:46:30.8 UT, 70.2 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 336.27802, -57.02190 which is equivalent to:
```
   RA(J2000)  = 22h 25m 6.72s
   Dec(J2000) = -57d 01' 18.8"
```
with an uncertainty of 3.3 arcseconds (radius, 90% containment). This location is 46 arcseconds from the BAT onboard position, within the BAT error circle.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.83e+20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 76 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	22:25:06.19 = 336.2758
  DEC(J2000) = -57:01:22.8  = -57.0230
```
with a 1-sigma error radius of about 0.5 arc sec. This position is 5.9 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.3 with a 1-sigma error of about 0.5 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is H. Ziaeepour (hz 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 Circular #8238
D. Fugazza, S. Covino, P. D'Avanzo, L.A. Antonelli, D. Malesani, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E. Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V.Testa, S.D. Vergani, F. Vitali report on behalf of the REM team:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 080916 on Sep 16 starting from about 20 s after the GRB time. We see a source not present in the 2MASS catalogue with approximately H~14.5 one minute after the burst at the coordinates RA=22:25:06.19, DEC=-57:01:24.1 (error 1 arcsec).
Further observations are in progress.
GCN Circular #8239
L.A. Antonelli, S. Covino, P. D'Avanzo,D. Malesani, D. Fugazza, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E. Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V.Testa, S.D. Vergani, F. Vitali report on behalf of the REM team:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 080916 (Ziaeepour et al. GCN 8237) on Sep 16 starting observations about 19.4 sec after the GRB. We clearly detect a NIR source at RA(J2000)=22:25:06.13, Dec.(J2000) =-57:01:22 with an uncertainty of 1" which is compatible with the position of the UVOT source (Ziaeepour et al. GCN 8237). At the beginning of the observation the source had a magnitude H=14.0+/-0.3, calibrated against 2MASS. The source showed a clear fading behavior during the REM observation.
GCN Circular #8241
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 2559 s of XRT Photon Counting mode data and 3 UVOT images for GRB 080916A, 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 = 336.27682, -57.02271 which is equivalent to:
```
RA (J2000): 22h 25m 6.44s
Dec (J2000): -57d 01' 21.7"
```
with an uncertainty of 1.8 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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method.
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #8243
W. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU), H. Ziaeepour (UCL-MSSL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 080916A (trigger #324895) (Ziaeepour, et al., GCN Circ. 8237). The BAT ground-calculated position is RA, Dec = 336.289, -57.026 deg, which is
```
   RA(J2000)  =  22h 25m 09.3s
   Dec(J2000) = -57d 01' 33.7"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 82%.
The mask-weighted light curve shows two overlapping FRED peaks starting at ~T-3 sec and ending at ~T+100 sec. T90 (15-350 keV) is 60 +- 7 sec (estimated error including systematics).
The time-averaged spectrum from T-2.4 to T+88.6 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.17 +- 0.21, and Epeak of 94.6 +- 23.0 keV (chi squared 48.0 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 4.0 +- 0.1 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+1.25 sec in the 15-150 keV band is 2.7 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.63 +- 0.05 (chi squared 64.5 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/324895/BA/
GCN Circular #8244
R.L.C. Starling (U. Leicester) and H. Ziaeepour (MSSL-UCL) report on behalf of the Swift-XRT team:
We have analysed the first two orbits of Swift XRT data for GRB 080916A (Ziaeepour et al., GCN Circ. 8237) from T0+70 s to T0+7440 s with total exposure time 3.4 ks. The enhanced X-ray position is given in Evans et al., GCN Circ. 8241.
The light curve can be represented by a 5-segment broken power law with an initial decay alpha1=1.3+0.4/-0.6 breaking at Tbk1=102+4/-6 s to a steep decay of alpha2=3.5+/-0.3 until Tbk2=190+25/-13 s. The light curve then flattens to alpha3=1.07+0.06/-0.3 and breaks at Tbk3=690+150/-140 s to a further steep decay of alpha4=2.9+2/-0.8. From Tbk4=1270+240/-220 s the decay becomes shallow again with alpha5=0.3+/-0.2.
The spectrum from 3.2 ks of Photon Counting mode data can be fit with an absorbed power law with photon index Gamma=2.1+/-0.2 and intrinsic absorption (in excess of the Galactic value of 1.8e20 cm-2) of nH=(2.6+0.7/-0.6)e21 cm-2. This is consistent with the spectrum formed from the initial 170 s of Windowed Timing mode data. The observed (unabsorbed) count rate to flux conversion is 1 count/s = 4.0e-11 (6.8e-11) erg/cm2/s.
The predicted count rate at T+24hr would be approximately 0.1 count/s if the decay continues on the current plateau-like phase.
This circular is an official product of the Swift-XRT team.
GCN Circular #8249
S. R. Oates (UCL-MSSL) and H. Ziaeepour (UCL-MSSL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 080916A, 78s after the BAT trigger (Ziaeepour et al., GCN 8237). We detect the afterglow in all of the UVOT filters at the position:
```
RA(J2000.0)  =  22:25:06.20
DEC(J2000.0) =  -57:01:22.9
```
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence). This position is consistent with the UVOT enhanced XRT position (Evans et al., GCN 8241) and the REM position (Fugazza et al., GCN 8238).
UVOT magnitudes are reported below for the finding charts (fc) and images:
```
Filter    Tstart(s)  Tstop   Expo(s)   Magnitude/3sigUL
-----------------------------------------------------
white (fc)    78    178        98       18.33 +/- 0.06
white        872    972        98       18.47 +/- 0.06
v     (fc)   182    582       393       17.55 +/- 0.06
v            978   1378       393       18.39 +/- 0.11
b           1458   1477        19       18.90 +/- 0.35
u            538    658        19       17.53 +/- 0.19
w1           613    633        19       18.25 +/- 0.39
m2           741   1565        39       18.42 +/- 0.40
w2           692    864        39       18.75 +/- 0.37
-----------------------------------------------------
```
These magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E{B-V} = 0.02 mag (Schlegel et al. 1998). The photometry is on the UVOT flight system described in Poole et al. (2008,MNRAS,383,627).
GCN Circular #8254
J. P. U. Fynbo, D. Malesani, J. Hjorth, J. Sollerman, C. C. Thoene (DARK), report on behalf of a larger collaboration.
We observed the field of GRB 080916A (Ziaeepour et al., GCN 8237) with the ESO VLT equipped with FORS1. Observations started on 2008 Sep 17.097 UT, 17.1 hr after the burst, for a total exposure time of 1 hr with the 300V grism. Based on MgII absorption and emission lines from [OII] and [OIII] we infer a redshift for GRB080916A of z=0.689 (based a preliminary wavelength calibration).
We acknowledge excellent support from the observing staff at Paranal, in particular Dominique Naef, Heidi Korhonen and Chris Lidman.
GCN Circular #8259
S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P. Oleynik, D. Svinkin, M. Ulanov and T. Cline, on behalf of the Konus-Wind team report:
The long GRB 080916A (Swift-BAT trigger # 324895: Ziaeepour et al., GCN 8237, Baumgartner et al. 8243) triggered Konus-Wind at T0=35121.715 s UT (09:45:21.715).
The burst light curve shows a single pulse with a duration of ~40 s.
As observed by Konus-Wind the burst had a fluence of 5.54(-0.66, +0.79)x10^-6 erg/cm2, and a 256-ms peak flux measured from T0+1.024 s of 1.05(-0.40, +0.41)x10^-6 erg/cm2/s (both in the 20 keV - 1 MeV energy range).
The time-integrated spectrum of the burst (from T0 to T0+33.024 s) is well fitted (in the 20 keV-1 MeV range) by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.00(-0.32, +0.38), and Ep = 129(-21, +33) keV (chi2 = 32.0/51 dof). Fitting by GRBM (Band) model yields only an upper limit on the high energy photon index: beta < -2.43.
All the quoted errors are at the 90% confidence level.
Assuming z = 0.689 (Fynbo et al., GCN 8254) and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda = 0.73, the isotropic energy release E_iso ~7x10^51 erg, the peak luminosity (L_iso)_max ~ 2x10^51 erg/s, and Ep_rest ~220 keV.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080916_T35121/
GCN Circular #8263
E. Bissaldi (MPE), S. McBreen (MPE), C.A. Wilson-Hodge (NASA/MSFC) and A. von Kienlin (MPE) report on behalf of the Fermi GBM Team:
"At 09:45:18 UT on 16 September 2008, the Fermi Gamma-ray Burst Monitor triggered and located GRB 080916A (trigger 243251119 / 080916406), which was also detected by Swift (Ziaeepour et al., GCN 8237) and Konus-Wind (Golenetskii et al., GCN 8259). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 331.5, Dec = -58.1 (equivalent to J2000 22h 06m, -58d 06'), with a statistical uncertainty of 3.2 degrees (radius, 1-sigma containment; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). This position is 2.8 deg from the Swift refined position (Evans et al., GCN 8241). The angle from the Fermi LAT boresight to the Swift position is 76 degrees.
This long GRB consists of several peaks, with the brightest one lasting from T0 to T0+13 s and a second peak from T0+13 s to T0+24 s followed by weaker emission. T90 (25-1000 keV) is about 60 sec, in agreement with the Swift-BAT refined analysis (Baumgartner et al., GCN 8243), and T50 (25-1000 keV) is about 25 s.
The time-averaged spectrum from T0 to T0+58 sec is adequately fit by a power law function with an exponential high energy cutoff. The power law index is -0.9 +/-0.1 and the cutoff energy, parameterized as Epeak, is 109 +/- 9 keV.
The fluence (25-1000 keV) is 1.5 (+/- 0.5)E-05 erg/cm2 and the peak flux (25-1000 keV) on the 1 s timescale is 4.5 (+/- 0.7) ph/cm2/s.
The spectral analysis results presented above are preliminary; final results will be published in the Fermi GBM GRB Catalog."
GCN Circular #8264
R. Holmes, M. Schubel, J. Haislip, D. Reichart, M. Nysewander, A. LaCluyze, K. Ivarsen, J. A. Crain, A. Foster, T. Brennan, and A. Trotter report:
Skynet observed the localization of GRB 080916A (Ziaeepour et al., GCN 8237) with four of the 16" PROMPT telescopes at CTIO beginning 56 seconds after the trigger in UBVRI.
We detect the afterglow (Fugazza et al., GCN 8238) in I. At 56 seconds after the burst we measure I ~ 17.7 mag (calibrated to 5 USNO B1 stars).
GCN Circular #8266
A. Rossi (Tautenburg Obs.), T. Kruehler, J. Greiner, A. Yoldas, C. Clemens, R. Filgas (all MPE Garching), A. Kupcu Yoldas (ESO) and G. Szokoly (Eoetvoes Univ., Budapest) report on behalf of the GROND team:
GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile), started observations of the field of GRB 080916A (Ziaeepour et al. GCN #8237) in g'r'i'z'JHK at 23:57:34 UT on 2008-09-16, 14 hours after the burst trigger.
We clearly detect the optical afterglow detected by UVOT (Ziaeepour et al. GCN #8237) and REM telescope (Fugazza et al. GCN #8238). Observations continued for 60 min and were repeated at the mid-time 06:40 UT for total 60 min.
Calibrating the field on USNO-B1 stars, we derive the following r band magnitudes, not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.019 mag (Schlegel et al. 1998):
```
midtime(s)	r	er
52239       	21.8	0.03
54054       	21.9	0.04
74076       	22.1	0.07
76260        	22.3	0.07
```
The total r band light curve is well fitted by power law with index of 0.81+- 0.13. Assuming the optical light curve continues the decline with the same power law index, we predict r' band magnitudes 23.4 at 3 days after the burst.
GCN Circular #8284
M. Suzuki, M. Kokubun, M. Ohno, T. Takahashi (ISAS/JAXA), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), Y.E. Nakagawa, T. Tamagawa (RIKEN), T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima U.), M. Tashiro, Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori (Univ. of Miyazaki), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:
The long GRB080916A (Swift/BAT trigger #324895; Ziaeepour et al., GCN 8237) was detected by the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 09:45:19.970 UT (=T0). The observed light curve shows a single peak at T0+0 s, followed by a second soft peak at ~T0+16 s with a total duration (T90) of about 20 seconds. The fluence in 100 - 500 keV was (2.57 +/- 0.32)x10^-6 erg/cm^2. The 1-s peak flux measured from T0+0 s was 1.54 (-0.12, +0.25) photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0-5s to T0+10s is fit by a single power-law with a photon index of 1.58 +/- 0.29 (chi^2/d.o.f = 13.1/12) in 100 - 500 keV. All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included.
The light curves with 1/64 sec time resolution for this burst are now available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN Report 167.1
GCN_Report 167.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_167_1.pdf by H. Ziaeepour at UCL/MSSL titled: "Final Swift report on GRB 080916A"
GCN Report 167.2
GCN_Report 167.2 has been posted: http://gcn.gsfc.nasa.gov/reports/report_167_2.pdf by H. Ziaeepour at UCL/MSSL titled: "Revised Final Swift report on GRB 080916A"
GCN Report 167.3
GCN_Report 167.3 has been posted: http://gcn.gsfc.nasa.gov/reports/report_167_3.pdf by H. Ziaeepour at UCL/MSSL titled: "Further Revised Final Swift report on GRB 080916A"

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Jochen Greiner, last update: 02-Nov-2008 [Disclaimer]