Gamma-ray Burst 090812

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:02:25 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.194d {+23h 32m 47s} (J2000),
                 353.318d {+23h 33m 16s} (current),
                 352.547d {+23h 30m 11s} (1950)
GRB_DEC:         -10.595d {-10d 35' 39"} (J2000),
                 -10.541d {-10d 32' 28"} (current),
                 -10.871d {-10d 52' 14"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4950 [cnts]    Image_Peak=260 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       27199 [cnts]
BKG_TIME:        21715.00 SOD {06:01:55.00} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15055 TJD;   224 DOY;   09/08/12
GRB_TIME:        21728.89 SOD {06:02:08.89} UT
GRB_PHI:         -36.71 [deg]
GRB_THETA:        26.50 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     23.38 [sigma]
IMAGE_SIGNIF:    10.25 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +0  +0  +0 +86  +0 
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 55' 01"}
SUN_DIST:        149.25 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.58d {+01h 46m 18s}  +16.64d {+16d 38' 36"}
MOON_DIST:        42.67 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.18 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      349.55, -7.03 [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 = 236.15,19.13 [deg].

GCN/BACODINE POSITION NOTICE

TITLE:        GCN/SIMBAD_NED NOTICE
NOTICE_DATE:  Wed Aug 12 06:02:57 UTC 2009
NOTICE_TYPE:  Swift-BAT Position search
TRIGGER_NUM:  359711
RA:           353.1940 (J2000)
DEC:          -10.5945 (J2000)
 
SIMBAD search for BAT_RA,Dec=353.1940,-10.5945,radius=10.0arcmin
 
Num   RA         Dec                    Name                        Type  Num_Pub  Distance

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:03:52 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.2012d {+23h 32m 48.28s} (J2000),
                 353.3255d {+23h 33m 18.12s} (current),
                 352.5541d {+23h 30m 12.99s} (1950)
GRB_DEC:         -10.6038d {-10d 36' 13.6"} (J2000),
                 -10.5507d {-10d 33' 02.3"} (current),
                 -10.8801d {-10d 52' 48.2"} (1950)
GRB_ERROR:       4.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       4.95e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.48 [sigma]
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21805.71 SOD {06:03:25.71} UT,   76.8 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.26 261.44 243.48
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 59"}
SUN_DIST:        149.25 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.59d {+01h 46m 21s}  +16.65d {+16d 38' 53"}
MOON_DIST:        42.68 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.19 [deg] galactic lon,lat of the burst
ECL_COORDS:      349.55, -7.04 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.70 arcmin from the BAT position.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:04:03 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.2012d {+23h 32m 48.2s} (J2000),
                 353.3255d {+23h 33m 18.1s} (current),
                 352.5541d {+23h 30m 12.9s} (1950)
GRB_DEC:         -10.6038d {-10d 36' 13.6"} (J2000),
                 -10.5507d {-10d 33' 02.3"} (current),
                 -10.8801d {-10d 52' 48.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       132 [cnts]
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21805.71 SOD {06:03:25.71} UT,   76.8 [sec] since BAT Trigger Time
CENTROID_X:      270.94,  raw= 271  [pixels]
CENTROID_Y:      287.29,  raw= 287  [pixels]
ROLL:            78.59 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -25.24
GRB_POS_XRT_Z:   -73.91
IMAGE_URL:       sw00359711000msxps_rw.img
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 59"}
SUN_DIST:        149.25 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.59d {+01h 46m 22s}  +16.65d {+16d 38' 55"}
MOON_DIST:        42.69 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.19 [deg] galactic lon,lat of the burst
ECL_COORDS:      349.55, -7.04 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:04:10 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.2012d {+23h 32m 48.2s} (J2000),
                 353.3255d {+23h 33m 18.1s} (current),
                 352.5541d {+23h 30m 12.9s} (1950)
GRB_DEC:         -10.6038d {-10d 36' 13.6"} (J2000),
                 -10.5507d {-10d 33' 02.3"} (current),
                 -10.8801d {-10d 52' 48.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       132 [cnts]
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21805.71 SOD {06:03:25.71} UT,   76.8 [sec] since BAT Trigger Time
CENTROID_X:      270.94,  raw= 271  [pixels]
CENTROID_Y:      287.29,  raw= 287  [pixels]
ROLL:            78.59 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -25.24
GRB_POS_XRT_Z:   -73.91
IMAGE_URL:       sw00359711000msxps_rw.img
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 59"}
SUN_DIST:        149.25 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.59d {+01h 46m 22s}  +16.65d {+16d 38' 56"}
MOON_DIST:        42.69 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.19 [deg] galactic lon,lat of the burst
ECL_COORDS:      349.55, -7.04 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:05:41 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.194d {+23h 32m 47s} (J2000),
                 353.318d {+23h 33m 16s} (current),
                 352.547d {+23h 30m 11s} (1950)
GRB_DEC:         -10.595d {-10d 35' 39"} (J2000),
                 -10.541d {-10d 32' 28"} (current),
                 -10.871d {-10d 52' 14"} (1950)
GRB_DATE:        15055 TJD;   224 DOY;   09/08/12
GRB_TIME:        21728.89 SOD {06:02:08.89} UT
TRIGGER_INDEX:   146
GRB_PHI:         -36.71 [deg]
GRB_THETA:        26.50 [deg]
DELTA_TIME:      52.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     23.38 [sigma]
IMAGE_SIGNIF:    10.25 [sigma]
LC_URL:          sw00359711000msb.lc
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 58"}
SUN_DIST:        149.25 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.61d {+01h 46m 25s}  +16.65d {+16d 39' 14"}
MOON_DIST:        42.70 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.18 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      349.55, -7.03 [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 = 236.15,19.13 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:06:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.180d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 04"} (J2000)
POINT_ROLL:      78.586d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21814.03 SOD {06:03:34.03} UT,   85.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.547
N_STARS:         21
X_OFFSET:        576 [pixels]
Y_OFFSET:        480 [pixels]
X_MAX:           1535 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0085.fits
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 58"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.61d {+01h 46m 27s}  +16.66d {+16d 39' 22"}
MOON_DIST:        42.72 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:06:51 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.180d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 04"} (J2000)
POINT_ROLL:      78.586d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21814.03 SOD {06:03:34.03} UT,   85.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.547
N_STARS:         21
X_OFFSET:        576 [pixels]
Y_OFFSET:        480 [pixels]
X_MAX:           1535 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0085.fits
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 57"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.62d {+01h 46m 28s}  +16.66d {+16d 39' 27"}
MOON_DIST:        42.72 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:06:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.180d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 04"} (J2000)
POINT_ROLL:      78.586d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21814.03 SOD {06:03:34.03} UT,   85.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.547
N_STARS:         21
X_OFFSET:        576 [pixels]
Y_OFFSET:        480 [pixels]
X_MAX:           1535 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0085.fits
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 58"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.61d {+01h 46m 27s}  +16.66d {+16d 39' 22"}
MOON_DIST:        42.72 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:07:29 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.180d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 04"} (J2000)
ROLL:            78.586d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21814.03 SOD {06:03:34.03} UT,   85.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     271749819
X_OFFSET:        961 [pixels]
Y_OFFSET:        848 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1121
Y_GRB_POS:       1008
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0090.fits
SUN_POSTN:       142.09d {+09h 28m 21s}  +14.92d {+14d 54' 57"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.62d {+01h 46m 29s}  +16.66d {+16d 39' 35"}
MOON_DIST:        42.73 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:07:44 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.180d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 04"} (J2000)
ROLL:            78.586d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  21814.03 SOD {06:03:34.03} UT,   85.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     271749819
X_OFFSET:        961 [pixels]
Y_OFFSET:        848 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1121
Y_GRB_POS:       1008
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0090.fits
SUN_POSTN:       142.09d {+09h 28m 22s}  +14.92d {+14d 54' 57"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.62d {+01h 46m 30s}  +16.66d {+16d 39' 37"}
MOON_DIST:        42.73 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:12:55 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22027.06 SOD {06:07:07.06} UT,   298.2 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.744
N_STARS:         11
X_OFFSET:        641 [pixels]
Y_OFFSET:        528 [pixels]
X_MAX:           1600 [pixels]
Y_MAX:           1487 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00359711000msufc0298.fits
SUN_POSTN:       142.09d {+09h 28m 22s}  +14.91d {+14d 54' 53"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.67d {+01h 46m 41s}  +16.68d {+16d 40' 37"}
MOON_DIST:        42.78 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:12:55 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22027.06 SOD {06:07:07.06} UT,   298.2 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.744
N_STARS:         11
X_OFFSET:        641 [pixels]
Y_OFFSET:        528 [pixels]
X_MAX:           1600 [pixels]
Y_MAX:           1487 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00359711000msufc0298.fits
SUN_POSTN:       142.09d {+09h 28m 22s}  +14.91d {+14d 54' 53"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.67d {+01h 46m 41s}  +16.68d {+16d 40' 37"}
MOON_DIST:        42.78 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:13:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22027.06 SOD {06:07:07.06} UT,   298.2 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.744
N_STARS:         11
X_OFFSET:        641 [pixels]
Y_OFFSET:        528 [pixels]
X_MAX:           1600 [pixels]
Y_MAX:           1487 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00359711000msufc0298.fits
SUN_POSTN:       142.09d {+09h 28m 22s}  +14.91d {+14d 54' 52"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.67d {+01h 46m 42s}  +16.68d {+16d 40' 43"}
MOON_DIST:        42.78 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:14:16 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
ROLL:            78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22027.06 SOD {06:07:07.06} UT,   298.2 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     271750032
X_OFFSET:        961 [pixels]
Y_OFFSET:        848 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1121
Y_GRB_POS:       1008
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0303.fits
SUN_POSTN:       142.09d {+09h 28m 23s}  +14.91d {+14d 54' 52"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.68d {+01h 46m 43s}  +16.68d {+16d 40' 53"}
MOON_DIST:        42.79 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:14:45 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
ROLL:            78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22027.06 SOD {06:07:07.06} UT,   298.2 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     271750032
X_OFFSET:        961 [pixels]
Y_OFFSET:        848 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1121
Y_GRB_POS:       1008
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0303.fits
SUN_POSTN:       142.09d {+09h 28m 23s}  +14.91d {+14d 54' 51"}
SUN_DIST:        149.27 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.69d {+01h 46m 44s}  +16.68d {+16d 40' 58"}
MOON_DIST:        42.79 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:18:10 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.2013d {+23h 32m 48.31s} (J2000),
                 353.3256d {+23h 33m 18.15s} (current),
                 352.5542d {+23h 30m 13.01s} (1950)
GRB_DEC:         -10.6045d {-10d 36' 16.1"} (J2000),
                 -10.5514d {-10d 33' 04.8"} (current),
                 -10.8808d {-10d 52' 50.7"} (1950)
GRB_ERROR:       3.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22443.00 SOD {06:14:03.00} UT,   714.1 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       142.10d {+09h 28m 23s}  +14.91d {+14d 54' 49"}
SUN_DIST:        149.26 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.72d {+01h 46m 52s}  +16.69d {+16d 41' 38"}
MOON_DIST:        42.81 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.19 [deg] galactic lon,lat of the burst
ECL_COORDS:      349.55, -7.04 [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.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:19:17 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     359711,   Seg_Num: 0
GRB_RA:          353.2022d {+23h 32m 48.52s} (J2000),
                 353.3265d {+23h 33m 18.36s} (current),
                 352.5551d {+23h 30m 13.23s} (1950)
GRB_DEC:         -10.6047d {-10d 36' 16.9"} (J2000),
                 -10.5516d {-10d 33' 05.6"} (current),
                 -10.8810d {-10d 52' 51.4"} (1950)
GRB_ERROR:       0.8 [arcsec radius, statistical only]
GRB_MAG:         18.62 +/- 0.16 [mag]
FILTER:          7, U
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22030.00 SOD {06:07:10.00} UT,   301.1 [sec] since BAT Trigger Time
SUN_POSTN:       142.10d {+09h 28m 23s}  +14.91d {+14d 54' 48"}
SUN_DIST:        149.26 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.73d {+01h 46m 54s}  +16.70d {+16d 41' 51"}
MOON_DIST:        42.82 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.93,-65.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      349.55, -7.04 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The UVOT position is 4.7 arcsec from the XRT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:19:59 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22603.52 SOD {06:16:43.52} UT,   874.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.610
N_STARS:         44
X_OFFSET:        401 [pixels]
Y_OFFSET:        288 [pixels]
X_MAX:           1840 [pixels]
Y_MAX:           1727 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0874.fits
SUN_POSTN:       142.10d {+09h 28m 23s}  +14.91d {+14d 54' 47"}
SUN_DIST:        149.28 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.73d {+01h 46m 56s}  +16.70d {+16d 41' 59"}
MOON_DIST:        42.84 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:19:59 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22603.52 SOD {06:16:43.52} UT,   874.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.610
N_STARS:         44
X_OFFSET:        401 [pixels]
Y_OFFSET:        288 [pixels]
X_MAX:           1840 [pixels]
Y_MAX:           1727 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0874.fits
SUN_POSTN:       142.10d {+09h 28m 23s}  +14.91d {+14d 54' 47"}
SUN_DIST:        149.28 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.73d {+01h 46m 56s}  +16.70d {+16d 41' 59"}
MOON_DIST:        42.84 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 12 Aug 09 06:20:27 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
POINT_ROLL:      78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22603.52 SOD {06:16:43.52} UT,   874.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.610
N_STARS:         44
X_OFFSET:        401 [pixels]
Y_OFFSET:        288 [pixels]
X_MAX:           1840 [pixels]
Y_MAX:           1727 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00359711000msufc0874.fits
SUN_POSTN:       142.10d {+09h 28m 24s}  +14.91d {+14d 54' 47"}
SUN_DIST:        149.28 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.74d {+01h 46m 57s}  +16.70d {+16d 42' 04"}
MOON_DIST:        42.84 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:21:13 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
ROLL:            78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22603.52 SOD {06:16:43.52} UT,   874.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     271750608
X_OFFSET:        960 [pixels]
Y_OFFSET:        847 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1120
Y_GRB_POS:       1007
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0879.fits
SUN_POSTN:       142.10d {+09h 28m 24s}  +14.91d {+14d 54' 46"}
SUN_DIST:        149.28 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.74d {+01h 46m 58s}  +16.70d {+16d 42' 13"}
MOON_DIST:        42.85 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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:     Wed 12 Aug 09 06:21:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     359711,   Seg_Num: 0
POINT_RA:        353.178d {+23h 32m 43s} (J2000)
POINT_DEC:       -10.601d {-10d 36' 01"} (J2000)
ROLL:            78.585d
IMG_START_DATE:  15055 TJD;   224 DOY;   09/08/12
IMG_START_TIME:  22603.52 SOD {06:16:43.52} UT,   874.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     271750608
X_OFFSET:        960 [pixels]
Y_OFFSET:        847 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1120
Y_GRB_POS:       1007
BINNING_INDEX:   1
IM_URL:          sw00359711000msuni0879.fits
SUN_POSTN:       142.10d {+09h 28m 24s}  +14.91d {+14d 54' 46"}
SUN_DIST:        149.28 [deg]   Sun_angle= 9.9 [hr] (West of Sun)
MOON_POSTN:       26.74d {+01h 46m 59s}  +16.70d {+16d 42' 16"}
MOON_DIST:        42.85 [deg]
MOON_ILLUM:      66 [%]
GAL_COORDS:       70.90,-65.17 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      349.53, -7.03 [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 #9768
M. Stamatikos (NASA/ORAU), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), C. Gronwall (PSU), C. Guidorzi (U Ferrara), C. B. Markwardt (CRESST/GSFC/UMD), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL) and R. L. C. Starling (U Leicester) report on behalf of the Swift Team:
At 06:02:08 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090812 (trigger=359711). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 353.194, -10.595 which is
```
   RA(J2000) = 23h 32m 47s
   Dec(J2000) = -10d 35' 39"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a triple-peaked structure with a duration of about 70 sec. The peak count rate was ~6500 counts/sec (15-350 keV), at ~25 sec after the trigger.
The XRT began observing the field at 06:03:25.7 UT, 76.8 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 353.20133, -10.60457 which is equivalent to:
```
   RA(J2000)  = 23h 32m 48.32s
   Dec(J2000) = -10d 36' 16.5"
```
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 43 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 2.26e+20 cm^-2 (Kalberla et al. 2005).
The initial flux in the 2.5 s image was 4.95e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 298 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	23:32:48.53 = 353.20222
  DEC(J2000) = -10:36:17.3  = -10.60481
```
with a 90%-confidence error radius of about 0.78 arc sec. This position is 5.1 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.62 with a 1-sigma error of about 0.16. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is M. Stamatikos (michael AT milkyway.gsfc.nasa.gov). 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 #9769
S. B. Cenko (UC Berkeley) reports on behalf of a larger collaboration:
We have imaged the field of GRB090812 (Stamatikos et al., GCN 9768) with the automated Palomar 60 inch telescope. Observations were obtained in the Sloan r', i', and z' filters beginning at 6:34 UT (~ 2.5 minutes after the burst).
Near the XRT afterglow we detect a point source at coordinates (J2000.0):
```
   RA: 23:32:48.55
   Dec: -10:36:17.0
```
with an estimated uncertainty of ~ 0.3" in each coordinate. This is consistent with the position reported by the UVOT.
We measure the following magnitudes for the source, calculated with respect to the SDSS DR7:
```
Time (UT mid-point)  Exposure (s)   Filter       Magnitude
-----------------------------------------------------------------------
06:05:02             60             r'           16.18
06:06:27             60             i'           16.39
06:09:28             60             r'           17.30
06:10:43             60             i'           17.34
```
The fading nature confirms this is the afterglow of GRB090812.
Further observations are planned.
GCN Circular #9770
R.J. Smith (Liverpool JMU), A. Gomboc (U. Ljubljana), C. Guidorzi (U. Ferrara), C.G. Mundell, I.A. Steele, A. Melandri, S. Kobayashi, C.J. Mottram, D.F. Bersier, Z. Cano (Liverpool JMU) report on behalf of a large collaboration:
On 2009 August 12 at 06:03:54 UT the 2-m Liverpool Telescope automatically began observing the Swift GRB 090812 (Stamatikos et al., GCN Circ. 9768) using the r' and i' filters.
We clearly detected the fading optical afterglow reported by Swift-UVOT and P60 (Cenko et al. GCN Circ. 9769) with the following values:
```
Mid Time   Delay from BAT   Total Exp  Filter     Mag
(UT)       trigger (s)      (s)
----------------------------------------------------------
06:03:59    111             10         r'    15.51 +- 0.04
06:06:26    258             10         r'    16.60 +- 0.10
----------------------------------------------------------
```
Magnitudes have been calibrated from nearby SDSS stars.
GCN Circular #9771
A. de Ugarte Postigo (INAF-OAB), J. Gorosabel (IAA-CSIC), J.P.U. Fynbo (DARK/NBI), K. Wiersema and N. Tanvir (Leicester) report on behalf of a larger collaboration
We have observed the afterglow of GRB 090812 (Stamatikos et al. GCNC 9768) using FORS2 at the VLT (Paranal observatory) starting at 06:54 UT (52min after the burst). In the spectrum we detect strong absorption lines, including Ly-alpha, SiII, SiII*, CII, SiIV, CIV, SiII, AlII, AlIII, FeII, ZnII, MnII and TiII at a common redshift of 2.452 which we identify as the redshift of the GRB. We also detect absorption lines from an unidentified intervening system. Further analysis is ongoing.
We acknowledge the excellent support from Paranal staff, in particular Jonathan Smoker, Cedric Ledoux and Karla Aubel.
GCN Circular #9772
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 456 s of XRT Photon Counting mode data and 1 UVOT images for GRB 090812, 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 = 353.20225, -10.60489 which is equivalent to:
```
RA (J2000): 23h 32m 48.54s
Dec (J2000): -10d 36' 17.6"
```
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) and Evans et al. (2009, arXiv:0812.3662).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #9773
Adria Updike (Clemson University), Arne Rau, Thomas Kruehler, Felipe Olivares, and Jochen Greiner (all MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 090812 (Swift trigger 359711; Stamatikos et al., GCN #9768) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile).
Due to cloud coverage, observations started only at 08:13 UT on August 12, 2 hours and 11 minutes after the GRB trigger. They were performed at an average seeing of 1.1" and at an average airmass of 1.2 with light cirrus, and continued until twilight.
We clearly detect the afterglow in stacked images (Stamatikos et al. GCN #9768, Cenko GCN #9769). Based on the first 4 min of total exposures, we estimate preliminary magnitudes and upper limits (all in AB system) of
```
g' = 22.15 +- 0.15 mag,
r' = 21.50 +- 0.08 mag,
i' = 21.30 +- 0.13 mag,
z' = 21.02 +- 0.12 mag,
J  = 20.57 +- 0.15 mag,
H  > 19.8 mag,
K  > 18.9 mag
```
The given magnitudes are calibrated against SDSS as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.02 mag in the direction of the burst (Schlegel et al. 1998).
The foreground extinction corrected spectral energy distribution is well fit with a pure power law and a spectral index of beta = 1.1+/-0.2 and no strong evidence of excess extinction.
The flux difference between the g' band magnitude and the extrapolation of the power law as defined by r'i'z'J is consistent with Lyman-alpha absorption at a redshift of 2.45 as reported by de Ugarte Postigo et al. (GCN #9771).
GCN Circular #9774
P. Schady (MSSL-UCL) and M. Stamatikos (NASA/ORAU) report on behalf of the Swift UVOT team:
The Swift/UVOT began settled observations of the field of GRB 090812 86s after the BAT trigger (Stamatikos et al., GCN Circ. 9768). An uncatalogued, fading source is detected in the UVOT white, v, b and u band filters at the position reported in Stamatikos et al. (GCN Circ. 9768), consistent with the refined XRT error circle (Goad et al., GCN Circ. 9772). The detection of the afterglow in the white, v, b and u filters is consistent with the spectroscopic redshift of z=2.452 reported by Ugarte Postigo et al. (GCN Circ. 9771). Early time UVOT obserations indicate a decay rate of alpha~1.5.
The magnitudes and 3-sigma upper limits for the UVOT observations of GRB 090812 in each filter are as follows:
```
Filter  T_start(s)  T_stop(s)  Exp(s)  Mag/3-sig UL
white      86         235       146    17.35+/-0.03
v          628        647       19     18.17+/-0.41
b          554        573       19     18.62+/-0.28
u          299        548       246    18.65+/-0.11
uvw1       677        1124      58     > 19.20
uvm2       652        1099      58     > 18.72
uvw2       603        1050      58     > 19.13
```
The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998). The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627).
GCN Circular #9776
K.Noda, A.Daikyuji, K.Kono, E.Sonoda, N.Ohmori, H.hayasi, M.Yamauchi (University of Miyazaki)
We have observed the field covering the error circle of GRB 090812 (Swift trigger 359711, GCN 9768, M. Stamatikos et al.) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 12:30:59 UT, about 6.5 hr after the Swift trigger time. We have compared our data of 30 sec exposures with the USNO-A2.0 catalog, There is no new source at the reported position. ((GCN 9768(M. Stamatikos et al.), GCN 9769(S. B. Cenko et al.) GCN 9770(R.J. Smith et al.), GCN 9772(M.R. Goad et al.) GCN 9773(Adria Updike et al.), GCN 9774(P. Schady et al.))
```
the upper limits are as follows:
--------------------------------------------------------------
Start(UT)   End(UT)    Num. of frames    Limit (mag.)
--------------------------------------------------------------
12:30:59    12:31:29          1            12.1
12:30:59    13:45:22         62            17.3
---------------------------------------------------------------
```
GCN Circular #9777
R. Starling (U. Leicester) and M. Stamatikos (NASA/ORAU) report on behalf of the Swift-XRT team:
We have analysed the first two orbits of Swift XRT data for GRB 090812 (trigger=359711, Stamatikos et al. GCN Circ. 9768) spanning T0+78 s to T0+12.4 ks. The UVOT-enhanced XRT position was given by Goad et al. in GCN Circ. 9748.
The light curve shows initial flaring, with two large flares overlaid on a power law of decay slope alpha1=1.5+/-0.5. The power law then breaks at approximately 960 s to a shallower slope of alpha=1.05+/-0.10.
A power law is an acceptable fit to a spectrum formed from the first orbit windowed timing (WT) mode data centred at T0+230 s, with a photon index, Gamma, of 1.97+/-0.03. The resulting column density at the source (z=2.452, de Ugarte Postigo et al. GCN Circ. 9771) is (1.00+/-0.09)e22 cm^-2 in addition to the Galactic column of 2.26e20 cm^-2 (Kalberla et al. 2005). The 0.3-10 keV observed (unabsorbed) count to flux conversion is 1 ct = 3.4e-11 (4.2e-11) erg/cm2/s. A fit to the spectrum formed from the first and second orbit photon counting (PC) mode data centred at T0+2760 s is consistent with the WT spectral results.
Interestingly, the X-ray spectral slope we derive is consistent with slope reported for the optical data from GROND, centred at T0+7860 s (Updike et al. GCN Circ. 9773.), which may imply a single spectral slope between the X-ray and optical bands several thousand seconds after the trigger.
While we only have two orbits of data, if we assume the light curve continues to decay with a power law of index alpha=1.05, the predicted count rate at T+24 hours will be 0.023 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.7e-13 (9.5e-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00359711.
This circular is an official product of the Swift-XRT team.
GCN Circular #9778
J. Wren, W.T. Vestrand, P.R. Wozniak, H. Davis, B. Norman of Los Alamos National Laboratory report:
The RAPTOR telescope system responded to Swift trigger 359711 (Stamatikos et al., GCN 9768) under good observing conditions. Our narrow-field instruments began observing the location at 06:02:32.9 UTC, 24.0 s after the Swift trigger (7.0 s after receipt of GCN message). We obtained simultaneous observations during the gamma-ray emitting interval in Cousins V, R, and I bands as well as unfiltered data. We detect the optical counterpart in all color bands. Initial analysis of our unfiltered data calibrated to the USNO-B1 R-band revals the counterpart brightening until ~T=70s after the trigger and then beginning a steady decline. The following table gives selected observations, not corrected for extinction, from this event. Further analysis of the multi-color data is underway.
```
t-mid(s)    exp(s)     mag     mag-err
--------------------------------------------
26.48        5.0      15.98    0.18
46.08        5.0      15.39    0.11
73.55        5.0      14.84    0.07
91.71        5.0      15.13    0.09
101.21       5.0      15.25    0.10
141.62      10.0      15.63    0.10
```
GCN Circular #9779
Z. Cano (Liverpool JMU), C. Guidorzi (U. Ferrara), C. Mundell, R.J. Smith, D. Bersier, A. Melandri, I.A. Steele, S. Kobayashi, C.J. Mottram, (Liverpool JMU), A. Gomboc (U. Ljubljana) report, on behalf of a large collaboration:
Following our report of observations on the Liverpool Telescope (Smith et al. GCN 9520) we continued monitoring the field of GRB090812 (Swift trigger 359711, Stamatikos et al. GCN 9768) on the Faulkes Telescope South (Australia) from 5.88 hours to 8.40 hours post burst in r' and i' bands.
We find from 6 x 300s stacked images:
```
t_exp          filter    t-T0          R-mag
----------------------------------------------------------
30min          i'        5.88 hours    22.43 +/- 0.25
30min          i'        8.40 hours    22.85 +/- 0.25
30min          r'        6.60 hours    22.31 +/- 0.09
----------------------------------------------------------
```
The calibration is still preliminary and determined against stars in the sdss field.
Finally, we find the decay rate in i' from 111s to 2.35ks post burst is consistent with alpha ~ 1.25 +/- 0.1
GCN Circular #9780
Alexander Kutyrev (CRESST/UMCP/GSFC), Jay Norris (U. Denver), report on behalf of the Goddard/U. Wyoming NIR camera collaboration.
We observed the afterglow position of GRB 090812 as reported by Cenko (GCN Circ. 9769) with the 2.3-meter WIRO telescope and the Goddard NIR camera, commencing 10:28 UT, 4.4 hrs after the Swift trigger (Stamatikos et al., GCN Circ. 9768).
Using stacked J-band images with a total exposure time of 1360 s, via comparison with two adjacent 2-MASS stars, we derive the following 3 sigma upper limit for the afterglow:
=A0=A0=A0=A0=A0=A0 Tmid (UT)=A0=A0=A0 Mag
=A0=A0=A0=A0=A0=A0=A0 10:46=A0=A0=A0=A0 J-band > 21.2
GCN Circular #9814
Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on behalf of a larger collaboration:
"We used the Very Large Array to observe the field of view toward GRB 090812 (GCN 9768) at a frequency of 8.46 GHz at two epochs, on 2009 Aug. 13.37 UT and Aug. 15.41 UT. The GRB radio afterglow is undetected in both the observations. The peak fluxes at the P60 optical afterglow position (GCN 9769) in the two observations are 104+/-43 uJy and 63+/-62 uJy, respectively.
The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN Circular #9816
K. Noda, E. Sonoda, N. Ohmori, K. Kono, H. Hayashi, A. Daikyuji, Y. Nishioka, M. Yamauchi (Univ. of Miyazaki), Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.), M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri, M. Tashiro, Y. Terada, A. Endo, K. Onda, T. Sugasahara (Saitama U.), Y. Urata (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), Y. E. Nakagawa, T. Tamagawa (RIKEN), S. Hong (Nihon U.), N. Vasquez (Tokyo Tech.), on behalf of the Suzaku WAM team, report:
The long GRB 090812 (Swift/BAT trigger #359711; Stamatikos et al., GCN 9768; Baumgartner et al., GCN 9775) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 2009-08-12 06:02:33.68 UT (=T0).
The observed light curve shows a double-peaked structure, starting at T0-30 s and ending at T0+40 s, with a total duration (T90) of about 36 s. The fluence in 100 - 1000 keV was 1.50(-0.46, +0.40) x10-6 erg/cm2. The 1-s peak flux measured from T0+2 s was 2.77(-0.35, +0.23) photons/cm2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0-30 s to T0+40s is well fitted by a power-law with exponential cutoff model:
```
  dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
  alpha:     1.31(-1.09, +0.81), and
  Epeak:     340(-138, +254) keV (chi2/d.o.f. = 36.6/37).
```
All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included.
The light curves for this burst will be available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN Circular #9821
V. Pal'shin, S. Golenetskii, R.Aptekar, E. Mazets, D. Frederiks, and T. Cline on behalf of the Konus-Wind team,
T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), and T. Ukwatta (GWU)
report:
The most intense pulse of the long GRB 090812 (Swift/BAT trigger #359711: Stamatikos et al., GCN Circ. 9768, Baumgartner et al. GCN Circ. 9775) triggered Konus-Wind at T0(KW)=21758.942 s UT (06:02:38.942). Since the Konus-Wind trigger record misses the early weaker part of this GRB, we have only Konus-Wind 3-channel spectral data for the whole burst which cover the energy range from 23 keV to 1.4 MeV. We performed the Konus-Wind and Swift/BAT joint spectral analysis of this GRB to derive the broad-band spectral and energetic parameters of this burst.
The time interval of the spectral data is chosen from T0(BAT)-6.7 to T0(BAT)+58.1 sec where T0(BAT) is the trigger time of BAT at 06:02:08.897 UTC. The energy ranges which we used in the joint spectral analysis are 23-1400 keV and 15-150 keV for the Konus-Wind and the Swift/BAT respectively. The spectral data of two instruments are fitted with the spectral model multiplied by the constant factor to take into account the systematic effective area uncertainties in the response matrices of each instrument.
The spectrum is well fitted with a power-law with exponential cutoff model: dN/dE ~ E^{alpha}*exp(-(2+alpha)*E/Epeak). The constant factors of each instrument agree within 15%. No systematic residual from the best fit model is seen in the spectral data of each instrument. The best fit spectral parameters are: alpha = -1.03(-0.06, +0.07) and Epeak = 586(-152, +243) keV (chi2/dof = 59.3/57). The best fit spectral parameters for the GRB (Band) model fixing beta = -2.5 are: alpha = -1.03 +/- 0.07, and Epeak = 572(-159, +251) keV (chi2/dof = 59.6/57). The energy fluence in the 15-1400 keV band calculated by a power-law with exponential cutoff model for this 64.8 sec interval is (2.61 +/- 0.34)x10^-5 erg/cm2 (assuming the constant factor of the Konus-Wind is fixed to 1).
Assuming z = 2.452 (de Ugarte Postigo et al. GCN Circ. 9771) and a standard cosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27, Omega_Lambda = 0.73, the isotropic energy release is E_iso = 4.4 (-0.6, +0.7)x10^53 erg in 1 keV to 10 MeV at the GRB rest frame extrapolating the best Band function fit fixing beta = -2.5, and the rest frame peak energy is Epeak_rest = 2.0(-0.5, +0.9) MeV.
All the quoted errors are at the 90% confidence level.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB090812_T21758/

GCN Circular #9999
J. Haislip, D. Reichart, K. Ivarsen, L. Cominsky, K. McLin, T. Graves, G. Spear, A. LaCluyze, A. Foster, J. Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. Nysewander report:
Skynet observed the Swift/BAT localization of GRB 090812 (Stamatikos et al., GCN 9768) with four of the 16" PROMPT telescopes at CTIO beginning 3.9 minutes after the trigger in UBVRI through variable cloud cover.
Skynet continued observing with the 14" GORT telescope at Hume Observatory in California beginning 48.4 minutes after the the trigger in RI.
We detect the afterglow (Stamatikos et al., GCN 9768). Stacking only images that increase the limiting magnitude yields:

mean                                                       1-sig. 1-sig.
time                                                       sys.   stat.
since                                            cal.      cal.   cal.
trig.   tel.     exp.     fil. magnitude         stars*    unc.   unc.
                  (# x s)                                   (mag)  (mag)

15.0 m  PROMPT-4 2 x 80   R    > 17.7 (3 sig.)   50 SDSS 7 0.008  0.010
15.0 m  PROMPT-5 2 x 80   I    > 17.0 (3 sig.)   20 SDSS 7 0.026  0.010
15.0 m  PROMPT-2 2 x 80   V    > 17.4 (3 sig.)   15 SDSS 7 0.030  0.020
32.1 m  PROMPT-3 2 x 80   B    > 18.5 (3 sig.)   25 SDSS 7 0.028  0.031
32.6 m  PROMPT-2 4 x 80   V    > 18.3 (3 sig.)   15 SDSS 7 0.039  0.010
                  + 1 x 40
32.7 m  PROMPT-4 5 x 80   R    > 18.4 (3 sig.)   50 SDSS 7 0.008  0.005
32.7 m  PROMPT-5 5 x 80   I    > 17.8 (3 sig.)   20 SDSS 7 0.026  0.005
62.0 m  GORT     6 x 80   R    > 18.8 (3 sig.)   34 SDSS 7 0.039  0.003
76.8 m  GORT     9 x 80   I    > 18.7 (3 sig.)   43 SDSS 7 0.097  0.003
117.3 m PROMPT-2 8 x 80   V    > 18.7 (3 sig.)   17 SDSS 7 0.019  0.006
119.1 m PROMPT-4 11 x 80  R    > 19.1 (3 sig.)   62 SDSS 7 0.229  0.003
119.2 m PROMPT-5 11 x 80  I    > 18.4 (3 sig.)   25 SDSS 7 0.117  0.003
120.0 m PROMPT-3 10 x 80  B    > 19.4 (3 sig.)   26 SDSS 7 0.085  0.011
3.2 h   PROMPT-3 24 x 80  B    > 21.3 (3 sig.)   26 SDSS 7 0.085  0.003
3.2 h   GORT     16 x 80  I    > 19.2 (3 sig.)   43 SDSS 7 0.097  0.002
3.4 h   GORT     20 x 80  R    > 20.0 (3 sig.)   34 SDSS 7 0.039  0.001
3.5 h   PROMPT-2 67 x 80  V    21.05 +0.35 -0.27 17 SDSS 7 0.019  0.001
3.5 h   PROMPT-5 66 x 80  I    20.60 +0.26 -0.21 25 SDSS 7 0.117  0.001
3.5 h   PROMPT-4 65 x 80  R    21.35 +0.28 -0.22 62 SDSS 7 0.229  0.001
3.6 h   PROMPT-3 37 x 80  U    > 19.5 (3 sig.)   30 SDSS 7 0.015  0.012

* Transformed using Jester et al., 2005, ApJ, 130, 873.

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Jochen Greiner, last update: 08-Oct-2009 [Disclaimer]