Gamma-ray Burst 120711B

(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:     Wed 11 Jul 12 03:12:22 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.668d {+22h 06m 40s} (J2000),
                 331.771d {+22h 07m 05s} (current),
                 331.257d {+22h 05m 02s} (1950)
GRB_DEC:         +60.020d {+60d 01' 10"} (J2000),
                 +60.081d {+60d 04' 51"} (current),
                 +59.775d {+59d 46' 30"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1597 [image_cnts]
TRIGGER_DUR:     64.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        16119 TJD;   193 DOY;   12/07/11
GRB_TIME:        11462.58 SOD {03:11:02.58} UT
GRB_PHI:         -93.12 [deg]
GRB_THETA:        17.07 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.65 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -2  +0  +1  +2  +0 
SUN_POSTN:       110.81d {+07h 23m 16s}  +22.06d {+22d 03' 30"}
SUN_DIST:         91.35 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.05d {+01h 08m 12s}  +11.19d {+11d 11' 14"}
MOON_DIST:        59.17 [deg]
MOON_ILLUM:      50 [%]
GAL_COORDS:      103.68,  3.46 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       16.10, 62.75 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
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 = 12.79,-19.23 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:17:25 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.668d {+22h 06m 40s} (J2000),
                 331.771d {+22h 07m 05s} (current),
                 331.257d {+22h 05m 02s} (1950)
GRB_DEC:         +60.020d {+60d 01' 10"} (J2000),
                 +60.081d {+60d 04' 51"} (current),
                 +59.775d {+59d 46' 30"} (1950)
GRB_DATE:        16119 TJD;   193 DOY;   12/07/11
GRB_TIME:        11462.58 SOD {03:11:02.58} UT
TRIGGER_INDEX:   20000
GRB_PHI:         -93.12 [deg]
GRB_THETA:        17.07 [deg]
DELTA_TIME:      320.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.65 [sigma]
LC_URL:          sw00526270000msb.lc
SUN_POSTN:       110.82d {+07h 23m 16s}  +22.06d {+22d 03' 28"}
SUN_DIST:         91.35 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.09d {+01h 08m 22s}  +11.20d {+11d 12' 03"}
MOON_DIST:        59.18 [deg]
MOON_ILLUM:      50 [%]
GAL_COORDS:      103.68,  3.46 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       16.10, 62.75 [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 an image 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 = 12.79,-19.23 [deg].  
COMMENTS:        The 3rd packet (of 3) was missing in the lightcurve data stream.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:28:52 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.6887d {+22h 06m 45.28s} (J2000),
                 331.7919d {+22h 07m 10.05s} (current),
                 331.2774d {+22h 05m 06.58s} (1950)
GRB_DEC:         +60.0193d {+60d 01' 09.4"} (J2000),
                 +60.0807d {+60d 04' 50.5"} (current),
                 +59.7747d {+59d 46' 28.8"} (1950)
GRB_ERROR:       5.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       8.75e-10 [erg/cm2/sec]
GRB_SIGNIF:      5.65 [sigma]
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11585.66 SOD {03:13:05.66} UT,   123.1 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.22 261.61 243.46
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       110.83d {+07h 23m 18s}  +22.06d {+22d 03' 25"}
SUN_DIST:         91.35 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.18d {+01h 08m 44s}  +11.23d {+11d 13' 54"}
MOON_DIST:        59.18 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.69,  3.45 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.12, 62.75 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.61 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:29:03 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.6887d {+22h 06m 45.2s} (J2000),
                 331.7919d {+22h 07m 10.0s} (current),
                 331.2774d {+22h 05m 06.5s} (1950)
GRB_DEC:         +60.0193d {+60d 01' 09.4"} (J2000),
                 +60.0807d {+60d 04' 50.5"} (current),
                 +59.7747d {+59d 46' 28.8"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       32 [cnts]
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11585.66 SOD {03:13:05.66} UT,   123.1 [sec] since BAT Trigger Time
CENTROID_X:      262.78,  raw= 263  [pixels]
CENTROID_Y:      285.97,  raw= 286  [pixels]
ROLL:            37.31 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -28.34
GRB_POS_XRT_Z:   -96.44
IMAGE_URL:       sw00526270000msxps_rw.img
SUN_POSTN:       110.83d {+07h 23m 18s}  +22.06d {+22d 03' 24"}
SUN_DIST:         91.35 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.19d {+01h 08m 45s}  +11.23d {+11d 13' 55"}
MOON_DIST:        59.18 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.69,  3.45 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.12, 62.75 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:29:09 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.6887d {+22h 06m 45.2s} (J2000),
                 331.7919d {+22h 07m 10.0s} (current),
                 331.2774d {+22h 05m 06.5s} (1950)
GRB_DEC:         +60.0193d {+60d 01' 09.4"} (J2000),
                 +60.0807d {+60d 04' 50.5"} (current),
                 +59.7747d {+59d 46' 28.8"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       32 [cnts]
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11585.66 SOD {03:13:05.66} UT,   123.1 [sec] since BAT Trigger Time
CENTROID_X:      262.78,  raw= 263  [pixels]
CENTROID_Y:      285.97,  raw= 286  [pixels]
ROLL:            37.31 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -28.34
GRB_POS_XRT_Z:   -96.44
IMAGE_URL:       sw00526270000msxps_rw.img
SUN_POSTN:       110.83d {+07h 23m 18s}  +22.06d {+22d 03' 24"}
SUN_DIST:         91.35 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.19d {+01h 08m 45s}  +11.23d {+11d 13' 56"}
MOON_DIST:        59.18 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.69,  3.45 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.12, 62.75 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:30:41 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 04"} (J2000)
POINT_ROLL:      37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11722.58 SOD {03:15:22.58} UT,   260.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.867
N_STARS:         190
X_OFFSET:        617 [pixels]
Y_OFFSET:        471 [pixels]
X_MAX:           1576 [pixels]
Y_MAX:           1430 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00526270000msufc0259.fits
SUN_POSTN:       110.83d {+07h 23m 19s}  +22.06d {+22d 03' 24"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.20d {+01h 08m 48s}  +11.24d {+11d 14' 11"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:31:09 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 04"} (J2000)
POINT_ROLL:      37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11722.58 SOD {03:15:22.58} UT,   260.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.867
N_STARS:         190
X_OFFSET:        617 [pixels]
Y_OFFSET:        471 [pixels]
X_MAX:           1576 [pixels]
Y_MAX:           1430 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00526270000msufc0259.fits
SUN_POSTN:       110.83d {+07h 23m 19s}  +22.06d {+22d 03' 24"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.20d {+01h 08m 49s}  +11.24d {+11d 14' 16"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [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 11 Jul 12 03:32:31 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 04"} (J2000)
ROLL:            37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11722.58 SOD {03:15:22.58} UT,   260.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     363669331
X_OFFSET:        936 [pixels]
Y_OFFSET:        790 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1096
Y_GRB_POS:       950
BINNING_INDEX:   1
IM_URL:          sw00526270000msuni0269.fits
SUN_POSTN:       110.83d {+07h 23m 19s}  +22.06d {+22d 03' 23"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.21d {+01h 08m 51s}  +11.24d {+11d 14' 29"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [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 11 Jul 12 03:32:41 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 04"} (J2000)
ROLL:            37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11722.58 SOD {03:15:22.58} UT,   260.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     363669331
X_OFFSET:        936 [pixels]
Y_OFFSET:        790 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1096
Y_GRB_POS:       950
BINNING_INDEX:   1
IM_URL:          sw00526270000msuni0269.fits
SUN_POSTN:       110.83d {+07h 23m 19s}  +22.06d {+22d 03' 23"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.22d {+01h 08m 52s}  +11.24d {+11d 14' 30"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [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:     Wed 11 Jul 12 03:35:36 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 03"} (J2000)
POINT_ROLL:      37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  12326.22 SOD {03:25:26.22} UT,   863.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.054
N_STARS:         86
X_OFFSET:        377 [pixels]
Y_OFFSET:        231 [pixels]
X_MAX:           1816 [pixels]
Y_MAX:           1670 [pixels]
DET_THRESH:      3
PHOTO_THRESH:    2
SL_URL:          sw00526270000msufc0863.fits
SUN_POSTN:       110.83d {+07h 23m 20s}  +22.06d {+22d 03' 22"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.24d {+01h 08m 57s}  +11.25d {+11d 14' 58"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:35:53 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     526270,   Seg_Num: 0
POINT_RA:        331.642d {+22h 06m 34s} (J2000)
POINT_DEC:       +60.001d {+60d 00' 03"} (J2000)
POINT_ROLL:      37.313d
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  12326.22 SOD {03:25:26.22} UT,   863.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.054
N_STARS:         86
X_OFFSET:        377 [pixels]
Y_OFFSET:        231 [pixels]
X_MAX:           1816 [pixels]
Y_MAX:           1670 [pixels]
DET_THRESH:      3
PHOTO_THRESH:    2
SL_URL:          sw00526270000msufc0863.fits
SUN_POSTN:       110.83d {+07h 23m 20s}  +22.06d {+22d 03' 22"}
SUN_DIST:         91.38 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.24d {+01h 08m 58s}  +11.25d {+11d 15' 01"}
MOON_DIST:        59.19 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.66,  3.45 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.05, 62.75 [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 Circular #13431
M. J. Page (UCL-MSSL), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), F. E. Marshall (NASA/GSFC), S. R. Oates (UCL-MSSL), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 03:11:02.58 UT, the Swift Burst Alert Telescope (BAT) triggered and located what may be GRB 120711B (trigger=526270). Swift slewed immediately to the position. The BAT on-board calculated location is RA, Dec 331.668, +60.020 which is
```
   RA(J2000) = 22h 06m 40s
   Dec(J2000) = 60d 01' 10"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve does not show any obvious variation, which is typical for an image trigger (64 second duration).
The XRT began observing the field at 03:13:05.6 UT, 123.1 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 331.69037, 60.02173 which is equivalent to:
```
   RA(J2000)  = 22h 06m 45.69s
   Dec(J2000) = +60d 01' 18.2"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 40 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 does not constrain the column density.
The initial flux in the 2.5 s image was 8.75e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 260 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the large, but uncertain extinction expected.
Due to the proximity of the source to the Galactic plane (3.46 degrees), the fact that this source was detected in the first image following the SAA, and the relative constancy of the XRT light curve, we believe that this is more likely to be a previously-unknown Galactic source rather than a GRB. However we will need the complete downlinked data to determine the nature of the source.
Burst Advocate for this burst is M. J. Page (mjp AT mssl.ucl.ac.uk). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 11 Jul 12 03:48:17 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     526270,   Seg_Num: 0
GRB_RA:          331.6904d {+22h 06m 45.69s} (J2000),
                 331.7936d {+22h 07m 10.45s} (current),
                 331.2792d {+22h 05m 06.99s} (1950)
GRB_DEC:         +60.0217d {+60d 01' 18.1"} (J2000),
                 +60.0831d {+60d 04' 59.2"} (current),
                 +59.7771d {+59d 46' 37.4"} (1950)
GRB_ERROR:       3.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16119 TJD;   193 DOY;   12/07/11
IMG_START_TIME:  11780.00 SOD {03:16:20.00} UT,   317.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       110.84d {+07h 23m 22s}  +22.05d {+22d 03' 18"}
SUN_DIST:         91.36 [deg]   Sun_angle= 9.3 [hr] (West of Sun)
MOON_POSTN:       17.34d {+01h 09m 22s}  +11.28d {+11d 17' 00"}
MOON_DIST:        59.20 [deg]
MOON_ILLUM:      49 [%]
GAL_COORDS:      103.69,  3.45 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.12, 62.75 [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:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN Circular #13449
A. A. Breeveld (MSSL-UCL) and M. J. Page (MSSL-UCL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120711B 260 s after the BAT trigger (Page et al., GCN Circ. 13431). No optical afterglow consistent with the XRT position (Page et al., GCN Circ. 13431) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           260          410          147         >21.7
white              260          734          186         >21.8
v                  417          784           58         >18.9
b                  516          710           39         >19.8
u                  491          858           58         >19.5
w1                 466          833           58         >18.9
m2                 441          809           58         >19.3
w2                 566         6472          208         >20.2
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 1.13 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #13450
T. N. Ukwatta (MSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), M. J. Page (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC) (i.e. the Swift-BAT team):
Using the data set from T-141 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120711B (trigger #526270) (Page, et al., GCN Circ. 13431). The BAT ground-calculated position is RA, Dec = 331.710, 59.996 deg, which is
```
   RA(J2000)  =  22h 06m 50.5s 
   Dec(J2000) = +59d 59' 46.0" 
```
with an uncertainty of 3.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 80%.
The mask-weighted light curve shows the emission starting ~T-100 sec, peaking at ~T+20 sec, and slowly decaying out to T+875 sec. T90 (15-350 keV) is 60 +- 19 sec (estimated error including systematics).
The time-averaged spectrum from T-12.1 to T+51.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.32. The fluence in the 15-150 keV band is 5.6 +- 1.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+13.11 sec in the 15-150 keV band is 0.4 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
Contrary to our GCN 13431, we now think that this trigger is very likely GRB, and not a new Galactic source.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/526270/BA/
GCN Circular #13453
K.L. Page (U. Leicester) and M. J. Page (UCL-MSSL) report on behalf of the Swift-XRT team:
We have analysed 4.5 ks of XRT data for GRB 120711B (Page et al. GCN Circ. 13431), from 208 s to 47.2 ks after the BAT trigger. The data comprise 106 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. Using 551 s of PC mode data and 2 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 331.69137, +60.02267 which is equivalent to:
```
RA (J2000): 22h 06m 45.93s
Dec(J2000): +60d 01' 21.6"
```
with an uncertainty of 1.8 arcsec (radius, 90% confidence).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.69 (+0.22, -0.17).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.8 (+0.5, -0.4). The best-fitting absorption column is 2.4 (+0.9, -0.8) x 10^22 cm^-2, in excess of the Galactic value of 7.2 x 10^21 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.5 (+0.4, -0.3) and a best-fitting absorption column of 2.9 (+0.7, -0.6) x 10^22 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 9.9 x 10^-11 (1.7 x 10^-10) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     2.9 (+0.7, -0.6) x 10^22 cm^-2
Galactic foreground: 7.2 x 10^21 cm^-2
Excess significance: 5.6 sigma
Photon index:	     1.5 (+0.4, -0.3)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00526270.
This circular is an official product of the Swift-XRT team.
GCN Circular #13465
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ), K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 120711B (Page et al., GCNC 13431) with the optical three color (g', Rc and Ic) CCD camera attached to the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory.
The observation started on 2012-07-11 14:35:55 UT (~11.4 h after the burst). We did not find any new point source within the XRT error circle (Page et al., GCNC 13431) in all the three bands.
Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'     Rc     Ic
----------------------------------------------------------------------
0.49154    14:58:51   4200.0    >22.1   >21.7  >20.5
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```

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Jochen Greiner, last update: 14-Jul-2012 [Disclaimer]