Gamma-ray Burst 120907A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:24:37 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     532871,   Seg_Num: 0
GRB_RA:           74.741d {+04h 58m 58s} (J2000),
                  74.893d {+04h 59m 34s} (current),
                  74.145d {+04h 56m 35s} (1950)
GRB_DEC:          -9.314d {-09d 18' 48"} (J2000),
                  -9.295d {-09d 17' 42"} (current),
                  -9.388d {-09d 23' 17"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4622 [cnts]    Image_Peak=207 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   148     E_range: 25-100 keV
BKG_INTEN:       29359 [cnts]
BKG_TIME:        1446.37 SOD {00:24:06.37} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16177 TJD;   251 DOY;   12/09/07
GRB_TIME:        1463.08 SOD {00:24:23.08} UT
GRB_PHI:         -70.55 [deg]
GRB_THETA:        37.64 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     15.49 [sigma]
IMAGE_SIGNIF:    11.33 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +1  +0  +0  +4  +0 
SUN_POSTN:       165.99d {+11h 03m 59s}   +5.99d {+05d 59' 19"}
SUN_DIST:         92.05 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.91d {+03h 43m 39s}  +19.78d {+19d 46' 42"}
MOON_DIST:        34.56 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       72.20,-31.82 [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 = 88.68,18.32 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(1.0<100sec) coincident with the FERMI_GBM event (trignum=368670267).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:25:02 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     368670267
GRB_RA:           80.240d {+05h 20m 58s} (J2000),
                  80.401d {+05h 21m 36s} (current),
                  79.607d {+05h 18m 26s} (1950)
GRB_DEC:          -1.560d {-01d 33' 35"} (J2000),
                  -1.548d {-01d 32' 52"} (current),
                  -1.609d {-01d 36' 30"} (1950)
GRB_ERROR:       9.97 [deg radius, statistical only]
DATA_SIGNIF:     8.90 [sigma]
DATA_INTERVAL:   1.024 [sec]
GRB_DATE:        16177 TJD;   251 DOY;   12/09/07
GRB_TIME:        1464.51 SOD {00:24:24.51} UT
GRB_PHI:         295.00 [deg]
GRB_THETA:       101.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       165.99d {+11h 03m 59s}   +5.99d {+05d 59' 19"}
SUN_DIST:         85.78 [deg]   Sun_angle= 5.7 [hr] (West of Sun)
MOON_POSTN:       55.92d {+03h 43m 40s}  +19.78d {+19d 46' 43"}
MOON_DIST:        32.12 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      203.63,-20.77 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       79.26,-24.64 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(1.0<100sec) coincident with the SWIFT_BAT event (trignum=532871).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:24:53 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     368670267
GRB_RA:           79.883d {+05h 19m 32s} (J2000),
                  80.047d {+05h 20m 11s} (current),
                  79.240d {+05h 16m 58s} (1950)
GRB_DEC:          +0.617d {+00d 37' 00"} (J2000),
                  +0.629d {+00d 37' 44"} (current),
                  +0.566d {+00d 33' 59"} (1950)
GRB_ERROR:       14.60 [deg radius, statistical plus systematic]
GRB_INTEN:       172 [cnts/sec]
DATA_SIGNIF:     5.10 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        16177 TJD;   251 DOY;   12/09/07
GRB_TIME:        1464.51 SOD {00:24:24.51} UT
GRB_PHI:         293.00 [deg]
GRB_THETA:       100.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      1.03
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   1%  Generic SGR
DETECTORS:       0,0,0, 1,1,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       165.99d {+11h 03m 59s}   +5.99d {+05d 59' 19"}
SUN_DIST:         85.90 [deg]   Sun_angle= 5.7 [hr] (West of Sun)
MOON_POSTN:       55.92d {+03h 43m 40s}  +19.78d {+19d 46' 43"}
MOON_DIST:        30.41 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      201.42,-20.03 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       79.05,-22.44 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 167.48,-9.63 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(1.0<100sec) coincident with the SWIFT_BAT event (trignum=532871).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:25:58 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.727d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 54"} (J2000)
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1545.10 SOD {00:25:45.10} UT,   82.0 [sec] since BAT Trigger Time
COUNTS:          2    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:28:11 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     532871,   Seg_Num: 0
GRB_RA:           74.741d {+04h 58m 58s} (J2000),
                  74.893d {+04h 59m 34s} (current),
                  74.145d {+04h 56m 35s} (1950)
GRB_DEC:          -9.314d {-09d 18' 48"} (J2000),
                  -9.295d {-09d 17' 42"} (current),
                  -9.388d {-09d 23' 17"} (1950)
GRB_DATE:        16177 TJD;   251 DOY;   12/09/07
GRB_TIME:        1463.08 SOD {00:24:23.08} UT
TRIGGER_INDEX:   148
GRB_PHI:         -70.55 [deg]
GRB_THETA:        37.64 [deg]
DELTA_TIME:      -69.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.49 [sigma]
IMAGE_SIGNIF:    11.33 [sigma]
LC_URL:          sw00532871000msb.lc
SUN_POSTN:       166.00d {+11h 03m 59s}   +5.99d {+05d 59' 16"}
SUN_DIST:         92.05 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.94d {+03h 43m 47s}  +19.78d {+19d 46' 56"}
MOON_DIST:        34.55 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       72.20,-31.82 [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 = 88.68,18.32 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:30:09 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     532871,   Seg_Num: 0
GRB_RA:           74.7486d {+04h 59m 00.33s} (J2000),
                  74.8999d {+04h 59m 35.98s} (current),
                  74.1523d {+04h 56m 36.54s} (1950)
GRB_DEC:          -9.3164d {-09d 18' 59.0"} (J2000),
                  -9.2979d {-09d 17' 52.4"} (current),
                  -9.3910d {-09d 23' 27.7"} (1950)
GRB_ERROR:       3.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1566.00 SOD {00:26:06.00} UT,   102.9 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 14"}
SUN_DIST:         92.04 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.96d {+03h 43m 51s}  +19.78d {+19d 47' 04"}
MOON_DIST:        34.55 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.47,-29.18 [deg] galactic lon,lat of the burst
ECL_COORDS:       72.21,-31.82 [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:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:31:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 54"} (J2000)
POINT_ROLL:      84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1605.14 SOD {00:26:45.14} UT,   142.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.079
N_STARS:         182
X_OFFSET:        346 [pixels]
Y_OFFSET:        257 [pixels]
X_MAX:           1785 [pixels]
Y_MAX:           1696 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00532871000msufc0142.fits
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 13"}
SUN_DIST:         92.07 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.97d {+03h 43m 53s}  +19.79d {+19d 47' 09"}
MOON_DIST:        34.53 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:31:53 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 54"} (J2000)
POINT_ROLL:      84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1605.14 SOD {00:26:45.14} UT,   142.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.079
N_STARS:         182
X_OFFSET:        346 [pixels]
Y_OFFSET:        257 [pixels]
X_MAX:           1785 [pixels]
Y_MAX:           1696 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00532871000msufc0142.fits
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 12"}
SUN_DIST:         92.07 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.98d {+03h 43m 54s}  +19.79d {+19d 47' 11"}
MOON_DIST:        34.53 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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:     Fri 07 Sep 12 00:31:58 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     532871,   Seg_Num: 0
GRB_RA:           74.7492d {+04h 59m 00.19s} (J2000),
                  74.9005d {+04h 59m 36.12s} (current),
                  74.1528d {+04h 56m 36.68s} (1950)
GRB_DEC:          -9.3141d {-09d 18' 50.7"} (J2000),
                  -9.2956d {-09d 17' 44.2"} (current),
                  -9.3887d {-09d 23' 19.4"} (1950)
GRB_ERROR:       2.4 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1566.00 SOD {00:26:06.00} UT,   102.9 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 12"}
SUN_DIST:         92.04 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.98d {+03h 43m 55s}  +19.79d {+19d 47' 12"}
MOON_DIST:        34.54 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.47,-29.18 [deg] galactic lon,lat of the burst
ECL_COORDS:       72.21,-31.82 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:32:46 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 54"} (J2000)
ROLL:            84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1605.14 SOD {00:26:45.14} UT,   142.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     368670414
X_OFFSET:        905 [pixels]
Y_OFFSET:        816 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1065
Y_GRB_POS:       976
BINNING_INDEX:   1
IM_URL:          sw00532871000msuni0152.fits
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 11"}
SUN_DIST:         92.07 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.98d {+03h 43m 56s}  +19.79d {+19d 47' 15"}
MOON_DIST:        34.52 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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:     Fri 07 Sep 12 00:32:56 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 54"} (J2000)
ROLL:            84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1605.14 SOD {00:26:45.14} UT,   142.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     368670414
X_OFFSET:        905 [pixels]
Y_OFFSET:        816 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1065
Y_GRB_POS:       976
BINNING_INDEX:   1
IM_URL:          sw00532871000msuni0152.fits
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 11"}
SUN_DIST:         92.07 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       55.99d {+03h 43m 57s}  +19.79d {+19d 47' 15"}
MOON_DIST:        34.52 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:34:47 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     532871,   Seg_Num: 0
GRB_RA:           74.7500d {+04h 59m 00.00s} (J2000),
                  74.9013d {+04h 59m 36.32s} (current),
                  74.1537d {+04h 56m 36.87s} (1950)
GRB_DEC:          -9.3150d {-09d 18' 53.9"} (J2000),
                  -9.2965d {-09d 17' 47.4"} (current),
                  -9.3896d {-09d 23' 22.6"} (1950)
GRB_ERROR:       0.6 [arcsec radius, statistical only]
GRB_MAG:         17.62 +/- 0.14 [mag]
FILTER:          7, U
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  1605.00 SOD {00:26:45.00} UT,   141.9 [sec] since BAT Trigger Time
SUN_POSTN:       166.00d {+11h 04m 00s}   +5.99d {+05d 59' 10"}
SUN_DIST:         92.04 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       56.00d {+03h 44m 00s}  +19.79d {+19d 47' 23"}
MOON_DIST:        34.53 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.47,-29.18 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       72.21,-31.82 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN Circular #13716
J. L. Racusin (NASA/GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), S. T. Holland (STScI), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/PSU) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 00:24:23 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120907A (trigger=532871). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 74.741, -9.314 which is
```
   RA(J2000)  =  04h 58m 58s
   Dec(J2000) = -09d 18' 48"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single pulse with a duration of about 5 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~2 sec after the trigger.
The XRT began observing the field at 00:25:45.1 UT, 82.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 74.7494, -9.3143 which is equivalent to:
```
   RA(J2000)  = 04h 58m 59.86s
   Dec(J2000) = -09d 18' 51.3"
```
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 29 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 5.35 x 10^20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 142 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	04:59:00.01 =  74.75005
  DEC(J2000) = -09:18:54.2  =  -9.31505
```
with a 90%-confidence error radius of about 0.63 arc sec. This position is 4.6 arc sec. from the center of the XRT error circle. The estimated magnitude is 17.63 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.09.
Burst Advocate for this burst is J. L. Racusin (judith.racusin AT 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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:42:55 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 53"} (J2000)
POINT_ROLL:      84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  2335.65 SOD {00:38:55.65} UT,   872.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.708
N_STARS:         141
X_OFFSET:        346 [pixels]
Y_OFFSET:        257 [pixels]
X_MAX:           1785 [pixels]
Y_MAX:           1696 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00532871000msufc0872.fits
SUN_POSTN:       166.01d {+11h 04m 01s}   +5.98d {+05d 59' 02"}
SUN_DIST:         92.08 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       56.07d {+03h 44m 17s}  +19.80d {+19d 47' 56"}
MOON_DIST:        34.49 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 07 Sep 12 00:43:27 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 53"} (J2000)
POINT_ROLL:      84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  2335.65 SOD {00:38:55.65} UT,   872.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.708
N_STARS:         141
X_OFFSET:        346 [pixels]
Y_OFFSET:        257 [pixels]
X_MAX:           1785 [pixels]
Y_MAX:           1696 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00532871000msufc0872.fits
SUN_POSTN:       166.01d {+11h 04m 02s}   +5.98d {+05d 59' 01"}
SUN_DIST:         92.08 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       56.08d {+03h 44m 18s}  +19.80d {+19d 47' 58"}
MOON_DIST:        34.48 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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:     Fri 07 Sep 12 00:44:20 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 53"} (J2000)
ROLL:            84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  2335.65 SOD {00:38:55.65} UT,   872.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     368671145
X_OFFSET:        905 [pixels]
Y_OFFSET:        816 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1065
Y_GRB_POS:       976
BINNING_INDEX:   1
IM_URL:          sw00532871000msuni0882.fits
SUN_POSTN:       166.01d {+11h 04m 02s}   +5.98d {+05d 59' 01"}
SUN_DIST:         92.08 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       56.08d {+03h 44m 20s}  +19.80d {+19d 48' 01"}
MOON_DIST:        34.48 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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:     Fri 07 Sep 12 00:44:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     532871,   Seg_Num: 0
POINT_RA:         74.724d {+04h 58m 54s} (J2000)
POINT_DEC:        -9.315d {-09d 18' 53"} (J2000)
ROLL:            84.306d
IMG_START_DATE:  16177 TJD;   251 DOY;   12/09/07
IMG_START_TIME:  2335.65 SOD {00:38:55.65} UT,   872.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     368671145
X_OFFSET:        905 [pixels]
Y_OFFSET:        816 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1065
Y_GRB_POS:       976
BINNING_INDEX:   1
IM_URL:          sw00532871000msuni0882.fits
SUN_POSTN:       166.01d {+11h 04m 02s}   +5.98d {+05d 59' 00"}
SUN_DIST:         92.08 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:       56.09d {+03h 44m 21s}  +19.80d {+19d 48' 02"}
MOON_DIST:        34.48 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:      208.46,-29.21 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       72.18,-31.81 [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 #13717
W. Zheng (U Mich), H. Flewelling (IfA/Hawaii), report on behalf of the ROTSE collaboration:
ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, Turkey, automatically responded to GRB 120907A (Swift trigger 532871; Racusin et al., GCN 13716). An automated response took the first image at 00:31:23.7 UT, 420 s after the burst, under fair conditions. We took 10 5-sec, 10 20-sec and 0 60-sec exposures. These unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on going.
We do not detect the candidate afterglow reported in GCN 13716. Individual images have limiting magnitudes ranging from 14.0-15.4; we set the following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
00:31:23.7 00:31:07.0 5 14.8 420 N
00:31:23.7 00:33:35.0 50 15.8 420 Y
00:33:40.0 00:38:20.0 200 16.4 557 Y
GCN Circular #13718
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, A.Kuznetsov, A.Sankovich Moscow Lomonosov State University, Sternberg Astronomical Institute,
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
V.Krushinski, I.Zalozhnich, A. Popov, A. Bourdanov, A. Punanova Ural Federal University
Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB120907A 375 s after notice time and 389 sec after GRB time at 2012-09-07 00:30:52 UT in a two polarizations. We are marginaly see SWIFT-UVOT optical transient (J. L. Racusin et. al. GCN 13716) on out first images. The unfiltred OT magnitude is about 17.5 mag. The long pointing time was due to some technical issues. The message may be cited.
GCN Circular #13719
T. Kruehler (DARK/NBI), D. Xu (WIS) and S. Schulze (PUC and MCSS) report on behalf of a larger collaboration:
We observed the field of the Swift GRB 120907A (Racusin et al., GCN 13716) with the NOT telescope equipped with StanCam. Eight I-band images with integration times of 120 s each were obtained on 2012-09-07 starting at 03:49 UT, which is roughly 3.4 hours after the trigger.
The optical afterglow (Racusin et al., GCN 13716) is clearly detected in our images. We derive a preliminary magnitude of
I = 20.2 +/- 0.1
centered at approximatly 3.6 hours after the trigger and assuming that the USNO star at RA(J2000) = 04:58:58.52, decl.(J2000) = -09:18:00.7 has an I-band magnitude of 15.28. An additional systematic uncertainty in the absolute brightness of about 0.3 mag is expected due to the calibration against the USNO catalog.
We are grateful to the NOT staff and observer, Anlaug Amanda Djupvik, for obtaining these observations.
GCN Circular #13720
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-61 to T+242 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120907A (trigger #532871) (Racusin, et al., GCN Circ. 13714). The BAT ground-calculated position is RA, Dec = 74.736, -9.323 deg which is
```
   RA(J2000)  =  04h 58m 56.7s 
   Dec(J2000) = -09d 19' 21.2" 
```
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 21%.
The mask-weighted light curve shows 2 or 3 somewhat overlapping peaks starting at ~T-1 sec, peaking at ~T+1 sec, and ending at ~T+20 sec. T90 (15-350 keV) is 16.9 +- 8.9 sec (estimated error including systematics).
The time-averaged spectrum from T-0.04 to T+18.76 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.73 +- 0.25. The fluence in the 15-150 keV band is 6.7 +- 1.1 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.10 sec in the 15-150 keV band is 2.9 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/532871/BA/
GCN Circular #13721
George Younes (MSFC/USRA) reports on behalf of the Fermi GBM Team:
"At 00:24:24.51 UT on 07 September 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120907A (trigger 368670267 / 120907017) which was also detected by the Swift/BAT (Barthelmy et al. 2012, GCN 13716). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 110 degrees.
The GBM light curve consists of a single pulse with a duration (T90) of about 5.8 s (50-300 keV). The time-averaged spectrum from T0-1.4 s to T0+0.7 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.75 +/- 0.25 and the cutoff energy, parameterized as Epeak, is 154.50 +/- 32.90 keV.
The event fluence (10-1000 keV) in this time interval is (7.8 +/- 1.1)E-07 ergs/cm^2. The 1-sec peak photon flux measured starting from T0-1.1 s in the 10-1000 keV band is 4.3 +/- 0.4 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #13722
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 4509 s of XRT Photon Counting mode data and 5 UVOT images for GRB 120907A, 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 = 74.74990, -9.31501 which is equivalent to:
```
RA (J2000): 04h 58m 59.98s
Dec (J2000): -09d 18' 54.0"
```
with an uncertainty of 1.6 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #13723
R. Sanchez-Ramirez, J. Gorosabel (IAA-CSIC), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI) and J.M. Gonzalez Perez (GTC) report on behalf of a larger collaboration:
We have obtained spectroscopy of the afterglow of GRB 120907A (Racusin et al. GCN 13716) with OSIRIS/ GTC (La Palma, Spain) on Sep 7.20647-7.23893 UT (4.55-5.33 hours post GRB). The observation consisted of 3x900s exposures using the R1000R grating, covering the range from 5100 to 10000 A with a resolution of ~1100.
In the combined spectrum we detect several absorption features corresponding to FeII, MgII, MgI and CaII at a common redshift of z=0.970, which we identify as the redshift of the GRB.
We acknowledge the excellent support of the GTC staff.
GCN Circular #13724
A. Maselli (INAF-IASFPA), V. Mangano (INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani (U. Leicester) and J.L. Racusin report on behalf of the Swift-XRT team:
We have analysed 16 ks of XRT data for GRB 120907A (Racusin et al. GCN Circ. 13716), from 93 s to 46.4 ks after the BAT trigger. The data comprise 76 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 13722).
The late-time light curve (from T0+4.5 ks) can be modelled with a power-law decay with a decay index of alpha=1.02 (+/-0.08).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.91 (+0.13, -0.12). The best-fitting absorption column is 10.0 (+3.1, -2.9) x 10^20 cm^-2, in excess of the Galactic value of 5.4 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.8 x 10^-11 (4.7 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     10.0 (+3.1, -2.9) x 10^20 cm^-2
Galactic foreground: 5.4 x 10^20 cm^-2
Excess significance: 2.7 sigma
Photon index:	     1.91 (+0.13, -0.12)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00532871.
This circular is an official product of the Swift-XRT team.
GCN Circular #13725
S. R. Oates (MSSL-UCL) and J. L. Racusin (NASA/GSFC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120907A 142 s after the BAT trigger (Racusin et al., GCN Circ. 13716). A source consistent with the enhanced XRT position (Goad et al. GCN Circ. 13722) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
  RA  (J2000) =  04:59:00.00 =  74.75002 (deg.)
  Dec (J2000) = -09:18:54.0  =  -9.31501 (deg.)
```
with an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

v                  449         6811        471         >19.5
b                  398         567          39         19.02 +/- 0.29
u                  142         392         246         17.67 +/- 0.08
w1                 498         666          40         18.27 +/- 0.32
m2                 473         1122         79         18.68 +/- 0.36
w2                 424         642          39         18.56 +/- 0.37
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.09 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #13726
T. Laskar, A. Zauderer and E. Berger (Harvard) report:
"We observed the position of GRB 120907A (GCN 13716) with the EVLA beginning 2012 September 7.46 UT (10.5 hours after the burst). No significant radio emission is detected at the enhanced Swift-XRT position (GCN 13724), the UVOT position (GCN 13725) or optical position (GCN 13719). Preliminary analysis indicates a three-sigma upper limit of 75 uJy at 5.8 GHz. Further observations are planned."
GCN Circular #13743
G. Petitpas (SAO), A. Zauderer, T. Laskar, E. Berger (Harvard) report on behalf of the SMA Rapid Transients (SMART) Key Project:
"We observed the position of GRB 120907A (Racusin et al; GCN 13716) with the Submillimeter Array (SMA) beginning 2012 Sep 7.63 UT (dt ~ 0.6 d). At a mean frequency of 230 GHz, we do not detect significant radio emission within the enhanced Swift/XRT error circle (Goad et al; GCN 13702) to a 3-sigma upper limit of 2.7 mJy. Beginning 2012 Sep 8.5 UT (dt ~ 1.5 d), we repeated our observations, and report a 3-sigma upper limit of 2.4 mJy.
We thank the SMA Observatory staff for its support."
GCN Circular #13761
V. Nevski (ISON-Kislovodsk Observatory), A. Volnova (SAI MSU/IKI), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger collaboration:
We observed the field of GRB 120907A (Racusin et al., GCN 13716) with Santel-400AN (0.4-m f/3) telescope =CFf ISON-Kislovodsk observatory starting on Sep. 07 (UT) 00:34:32, i.e. ~10.2 minutes after burst trigger. We took several unfiltered images of 30 s and 60 s exposures. In a stacked images we clearly detect optical afterglow of GRB 120907A (Racusin et al., GCN 13716; Gorbovskoy et al., GCN 13718; Kruehler et al., GCN 13719). A preliminary photometry of stacked frames is based on the USNO-B1.0 (R2) nearby stars:
```
T_start,     T0+,       Exp,     Filter,       OT
(UT)          mid (d)   (s)

00:34:32  0.00899 10x30    none      18.55+/-0.09
00:51:45  0.02120   5x60    none      18.95+/-0.13
00:58:09  0.02980   8x60    none      19.52+/-0.20
01:16:32  0.04339   8x60    none      19.50+/-0.20
```

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Jochen Greiner, last update: 13-Sep-2012 [Disclaimer]