Gamma-ray Burst 080802

(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 02 Aug 08 15:14:28 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     318832,   Seg_Num: 0
GRB_RA:          270.7260d {+18h 02m 54.2s} (J2000),
                 270.8663d {+18h 03m 27.9s} (current),
                 269.9093d {+17h 59m 38.2s} (1950)
GRB_DEC:         -32.3319d {-32d 19' 54.8"} (J2000),
                 -32.3312d {-32d 19' 52.4"} (current),
                 -32.3334d {-32d 20' 00.3"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.47e-09 [erg/cm2/sec]
GRB_SIGNIF:      7.14 [sigma]
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54819.69 SOD {15:13:39.69} UT,   54819.7 [sec] since BAT Trigger Time
TAM[0-3]:        327.68 237.29 261.35 243.63
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       133.14d {+08h 52m 33s}  +17.55d {+17d 33' 16"}
SUN_DIST:        139.24 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.57d {+09h 54m 17s}  +11.91d {+11d 54' 42"}
MOON_DIST:       123.51 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.94, -4.92 [deg] galactic lon,lat of the burst
ECL_COORDS:      270.62, -8.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:14:38 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     318832,   Seg_Num: 0
GRB_RA:          270.7260d {+18h 02m 54.2s} (J2000),
                 270.8663d {+18h 03m 27.9s} (current),
                 269.9093d {+17h 59m 38.2s} (1950)
GRB_DEC:         -32.3319d {-32d 19' 54.8"} (J2000),
                 -32.3312d {-32d 19' 52.4"} (current),
                 -32.3334d {-32d 20' 00.3"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       51 [cnts]
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54819.69 SOD {15:13:39.69} UT,   54819.7 [sec] since BAT Trigger Time
CENTROID_X:      271.77,  raw= 272  [pixels]
CENTROID_Y:      298.86,  raw= 299  [pixels]
ROLL:            259.26 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   2.03
GRB_POS_XRT_Z:   -71.95
IMAGE_URL:       sw00318832000msxps_rw.img
SUN_POSTN:       133.14d {+08h 52m 33s}  +17.55d {+17d 33' 16"}
SUN_DIST:        139.24 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.57d {+09h 54m 17s}  +11.91d {+11d 54' 40"}
MOON_DIST:       123.51 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.94, -4.92 [deg] galactic lon,lat of the burst
ECL_COORDS:      270.62, -8.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:14:43 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     318832,   Seg_Num: 0
GRB_RA:          270.7260d {+18h 02m 54.2s} (J2000),
                 270.8663d {+18h 03m 27.9s} (current),
                 269.9093d {+17h 59m 38.2s} (1950)
GRB_DEC:         -32.3319d {-32d 19' 54.8"} (J2000),
                 -32.3312d {-32d 19' 52.4"} (current),
                 -32.3334d {-32d 20' 00.3"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       51 [cnts]
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54819.69 SOD {15:13:39.69} UT,   54819.7 [sec] since BAT Trigger Time
CENTROID_X:      271.77,  raw= 272  [pixels]
CENTROID_Y:      298.86,  raw= 299  [pixels]
ROLL:            259.26 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   2.03
GRB_POS_XRT_Z:   -71.95
IMAGE_URL:       sw00318832000msxps_rw.img
SUN_POSTN:       133.14d {+08h 52m 33s}  +17.55d {+17d 33' 16"}
SUN_DIST:        139.24 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.57d {+09h 54m 17s}  +11.91d {+11d 54' 38"}
MOON_DIST:       123.51 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.94, -4.92 [deg] galactic lon,lat of the burst
ECL_COORDS:      270.62, -8.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:16:03 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     318832,   Seg_Num: 0
GRB_RA:          270.748d {+18h 02m 60s} (J2000),
                 270.889d {+18h 03m 33s} (current),
                 269.932d {+17h 59m 44s} (1950)
GRB_DEC:         -32.333d {-32d 19' 59"} (J2000),
                 -32.333d {-32d 19' 56"} (current),
                 -32.335d {-32d 20' 04"} (1950)
GRB_DATE:        14680 TJD;   215 DOY;   08/08/02
GRB_TIME:        54741.07 SOD {15:12:21.07} UT
TRIGGER_INDEX:   298
GRB_PHI:         173.32 [deg]
GRB_THETA:         4.87 [deg]
DELTA_TIME:      -5.00 [sec]
TRIGGER_DUR:      [sec],  copy from BAT_POS unavailable
SOLN_STATUS:     0x0
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    0.00 [sigma]
LC_URL:          sw00318832000msb.lc
SUN_POSTN:       133.14d {+08h 52m 34s}  +17.55d {+17d 33' 15"}
SUN_DIST:        139.26 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.58d {+09h 54m 20s}  +11.91d {+11d 54' 19"}
MOON_DIST:       123.52 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.95, -4.94 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      270.64, -8.90 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:        This does not match any source in the ground catalog.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:18:17 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.749d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.327d {-32d 19' 35"} (J2000)
POINT_ROLL:      259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54826.91 SOD {15:13:46.91} UT,   54826.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.701
N_STARS:         190
X_OFFSET:        464 [pixels]
Y_OFFSET:        504 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1463 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00318832000msufc239382826.fits
SUN_POSTN:       133.14d {+08h 52m 34s}  +17.55d {+17d 33' 14"}
SUN_DIST:        139.26 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.60d {+09h 54m 25s}  +11.90d {+11d 53' 45"}
MOON_DIST:       123.50 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:19:02 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.749d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.327d {-32d 19' 35"} (J2000)
POINT_ROLL:      259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54826.91 SOD {15:13:46.91} UT,   54826.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.701
N_STARS:         190
X_OFFSET:        464 [pixels]
Y_OFFSET:        504 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1463 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00318832000msufc239382826.fits
SUN_POSTN:       133.14d {+08h 52m 34s}  +17.55d {+17d 33' 13"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.61d {+09h 54m 27s}  +11.89d {+11d 53' 34"}
MOON_DIST:       123.49 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:20:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.749d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.327d {-32d 19' 35"} (J2000)
ROLL:            259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54826.91 SOD {15:13:46.91} UT,   54826.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     239382829
X_OFFSET:        912 [pixels]
Y_OFFSET:        796 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1072
Y_GRB_POS:       956
BINNING_INDEX:   1
IM_URL:          sw00318832000msuni239382826.fits
SUN_POSTN:       133.14d {+08h 52m 34s}  +17.55d {+17d 33' 13"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.62d {+09h 54m 29s}  +11.89d {+11d 53' 16"}
MOON_DIST:       123.48 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:19:54 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.749d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.327d {-32d 19' 35"} (J2000)
ROLL:            259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54826.91 SOD {15:13:46.91} UT,   54826.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     239382829
X_OFFSET:        912 [pixels]
Y_OFFSET:        796 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1072
Y_GRB_POS:       956
BINNING_INDEX:   1
IM_URL:          sw00318832000msuni239382826.fits
SUN_POSTN:       133.14d {+08h 52m 34s}  +17.55d {+17d 33' 13"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.62d {+09h 54m 28s}  +11.89d {+11d 53' 21"}
MOON_DIST:       123.48 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [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 02 Aug 08 15:25:50 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.748d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.326d {-32d 19' 34"} (J2000)
POINT_ROLL:      259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54932.93 SOD {15:15:32.93} UT,   54932.9 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        3.142
N_STARS:         190
X_OFFSET:        592 [pixels]
Y_OFFSET:        476 [pixels]
X_MAX:           1551 [pixels]
Y_MAX:           1435 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00318832000msufc239382932.fits
SUN_POSTN:       133.15d {+08h 52m 35s}  +17.55d {+17d 33' 09"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.67d {+09h 54m 41s}  +11.86d {+11d 51' 53"}
MOON_DIST:       123.42 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 02 Aug 08 15:26:41 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.748d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.326d {-32d 19' 34"} (J2000)
POINT_ROLL:      259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54932.93 SOD {15:15:32.93} UT,   54932.9 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        3.142
N_STARS:         190
X_OFFSET:        592 [pixels]
Y_OFFSET:        476 [pixels]
X_MAX:           1551 [pixels]
Y_MAX:           1435 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00318832000msufc239382932.fits
SUN_POSTN:       133.15d {+08h 52m 35s}  +17.55d {+17d 33' 08"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.68d {+09h 54m 43s}  +11.86d {+11d 51' 41"}
MOON_DIST:       123.41 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [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 02 Aug 08 15:27:25 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.748d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.326d {-32d 19' 34"} (J2000)
ROLL:            259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54932.93 SOD {15:15:32.93} UT,   54932.9 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     239382935
X_OFFSET:        912 [pixels]
Y_OFFSET:        796 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1072
Y_GRB_POS:       956
BINNING_INDEX:   1
IM_URL:          sw00318832000msuni239382932.fits
SUN_POSTN:       133.15d {+08h 52m 35s}  +17.55d {+17d 33' 08"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.69d {+09h 54m 45s}  +11.86d {+11d 51' 30"}
MOON_DIST:       123.41 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [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 02 Aug 08 15:27:55 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     318832,   Seg_Num: 0
POINT_RA:        270.748d {+18h 02m 60s} (J2000)
POINT_DEC:       -32.326d {-32d 19' 34"} (J2000)
ROLL:            259.262d
IMG_START_DATE:  14680 TJD;   215 DOY;   08/08/02
IMG_START_TIME:  54932.93 SOD {15:15:32.93} UT,   54932.9 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     239382935
X_OFFSET:        912 [pixels]
Y_OFFSET:        796 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1072
Y_GRB_POS:       956
BINNING_INDEX:   1
IM_URL:          sw00318832000msuni239382932.fits
SUN_POSTN:       133.15d {+08h 52m 36s}  +17.55d {+17d 33' 08"}
SUN_DIST:        139.25 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      148.69d {+09h 54m 46s}  +11.86d {+11d 51' 22"}
MOON_DIST:       123.40 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      358.96, -4.94 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      270.64, -8.89 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #8051
```
TITLE:   GCN CIRCULAR
NUMBER:  8051
SUBJECT: GRB 080802: Swift detection of a probable burst
DATE:    08/08/02 15:46:43 GMT
FROM:    David Palmer at LANL  
```
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), M. M. Chester (PSU), C. B. Markwardt (CRESST/GSFC/UMD), D. M. Palmer (LANL) and E. Troja (INAF-IASFPA) report on behalf of the Swift Team:
At 15:12:21 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080802 (trigger=318832). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 270.748, -32.333 which is
```
   RA(J2000) = 18h 02m 60s
   Dec(J2000) = -32d 19' 59"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 50 sec. The peak count rate was ~1000 counts/sec (15-350 keV), at ~2 sec after the trigger.
The XRT began observing the field at 15:13:39.7 UT, 78 seconds after the BAT trigger. Using promptly downlinked data we find a bright, variable, uncatalogued X-ray source located at RA, Dec 270.72692, -32.33395 which is equivalent to:
```
   RA(J2000)  = 18h 02m 54.46s
   Dec(J2000) = -32d 20' 02.2"
```
with an uncertainty of 3.1 arcseconds (radius, 90% containment). This is 1.1 arcminutes from the BAT position and within its error radius.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (2.75e+21 cm^-2, Kalberla et al. 2005), with an excess column of 2.3 (+2.63/-2.21) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 1.47e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 86 seconds after the BAT trigger. No afterglow candidate is apparent in the initial data products. The 2.7'x2.7' sub-image covers 25% of the BAT error circle and 100% of the XRT error circle. The typical 3-sigma upper limit has been about 18.5 mag. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction, which at this location is large and uncertain.
Because this source is near the Galactic center, this event may be a local transient rather than a cosmological GRB. However, no known sources are found at the XRT position in either SIMBAD or NED.
No BAT_POSITION notice was available due to a TDRSS hand-over at the time of the burst.
GCN Circular #8052
H. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), 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) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+388 sec from the recent telemetry downlink, we report further analysis of BAT GRB 080802 (trigger #318832) (Baumgartner, et al., GCN Circ. 8051). The BAT ground-calculated position is RA, Dec = 270.729, -32.329 deg which is
```
   RA(J2000)  =  18h 02m 55.0s 
   Dec(J2000) = -32d 19' 45.6" 
```
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows several overlapping peaks starting at ~T-40 sec and ending at ~T+180. T90 (15-350 keV) is 176 +- 50 sec (estimated error including systematics).
The time-averaged spectrum from T-31.1 to T+176.9 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.76 +- 0.19. The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-7.56 sec in the 15-150 keV band is 0.3 +- 0.0 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
Given the Galactic lon,lat being in the bulge, we can not rule out a non-GRB source for this trigger. All other factors point to a GRB.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/318832/BA/
GCN Circular #8053
Adria C. Updike (Clemson U), James Neff (College of Charleston), and Dieter H. Hartmann (Clemson U) report:
We observed the field of GRB 080802 (GCN 8051, Baumgartner et al.) using the 0.5m UVI (University of the Virgin Islands) telescope at St. Thomas for 5 minutes in the R band, beginning 00:12 UT (~9 hours after the trigger). We detect no new sources within the XRT error circle to a limiting magnitude of R ~ 18.5 as calibrated against the USNO B1.0 catalog. Further observations we hampered by cloud cover.
This message may be cited.
GCN Circular #8054
M.C. Stroh (PSU) reports on behalf of the Swift-XRT team:
We have analyzed the first two orbits of Swift-XRT data obtained for GRB 080802 (Baumgartner et al., GCN Circ. 8051), totaling 81s of Windowed Timing and 2.4ks of Photon Counting data.
The X-ray light-curve begins with a single flare that peaks to ~40 cts/ s near T+100 seconds. The rest of the light-curve can be fit by a single broken power-law with an initial decay index of 2.91 +/- 0.33, second decay index of -0.51 +/- 0.25 and a break near T+1000s. Since the second decay index indicates brightening, we cannot accurately predict counting rates at T+24 or T+48 hours.
The spectrum from the Windowed Timing data can be fit with a power-law in excess of the Galactic value (2.75e21 cm-2, Kalberla et al. 2005), with a column density of 4.8 (+2.0/-1.7)e21 cm^-2 and a photon index of 1.40 (+0.24/-0.22). The observed (unabsorbed) 0.3-10 keV flux is 4.78e-10 (4.95e-10) ergs/cm^2/s.
This is an official product of the Swift-XRT team.
GCN Circular #8055
P. Schady (MSSL-UCL) and W.H. Baumgartner (GSFC/UMBC) report on behalf of the Swift/UVOT team:
The Swift/UVOT observed the field of GRB 080802 starting 87 s after the BAT trigger (Baumgartner et al., GCN Circ. 8051). We do not find a source in any of the UVOT observations inside the XRT error circle (Baumgartner et al., GCN Circ. 8051). The 3-sigma upper limits for detecting a source in the first white and v finding charts (FC) exposure and co-added frames are:
```
Filter          T_start T_stop  Exp     Mag (3-sigma UL)
                 (s)     (s)     (s)
=========================================================
white (FC)      87      186     100     > 20.0
white           4803    5002    200     > 20.4
v (FC)          193     406     213     > 18.7
v               5214    5413    200     > 18.7
b               4598    6189    356     > 20.1
u               4393    6028    400     > 19.9
uvw1            4188    5822    400     > 19.8
uvm2            3983    5618    400     > 19.7
uvw2            5009    5208    200     > 19.5
```
The values quoted above are not corrected for the expected Galactic extinction corresponding to a reddening of E(B-V) = 0.80 mag in the direction of the burst (Schlegel et al. 1998).

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Jochen Greiner, last update: 03-Aug-2008 [Disclaimer]