Gamma-ray Burst 130812A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 12 Aug 13 22:23:07 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     566228,   Seg_Num: 0
GRB_RA:           92.402d {+06h 09m 37s} (J2000),
                  92.559d {+06h 10m 14s} (current),
                  91.827d {+06h 07m 19s} (1950)
GRB_DEC:         -13.295d {-13d 17' 42"} (J2000),
                 -13.299d {-13d 17' 54"} (current),
                 -13.285d {-13d 17' 05"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       1987 [cnts]    Image_Peak=209 [image_cnts]
TRIGGER_DUR:     0.256 [sec] 
TRIGGER_INDEX:   120     E_range: 15-50 keV
BKG_INTEN:       34547 [cnts]
BKG_TIME:        80557.09 SOD {22:22:37.09} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16516 TJD;   224 DOY;   13/08/12
GRB_TIME:        80572.58 SOD {22:22:52.58} UT
GRB_PHI:           9.23 [deg]
GRB_THETA:        29.44 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     26.09 [sigma]
IMAGE_SIGNIF:    11.67 [sigma]
MERIT_PARAMS:     +1  +0  +0  -2  +1  +1  +0  +0 -53  +0 
SUN_POSTN:       142.76d {+09h 31m 02s}  +14.70d {+14d 42' 01"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.78d {+13h 55m 06s}  -12.68d {-12d 40' 30"}
MOON_DIST:       111.65 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       92.92,-36.71 [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 = 156.28,-20.34 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 12 Aug 13 22:24:17 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.416d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.293d {-13d 17' 35"} (J2000)
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80649.62 SOD {22:24:09.62} UT,   77.0 [sec] since BAT Trigger Time
COUNTS:          1    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        0    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:     Mon 12 Aug 13 22:26:43 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     566228,   Seg_Num: 0
GRB_RA:           92.402d {+06h 09m 37s} (J2000),
                  92.559d {+06h 10m 14s} (current),
                  91.827d {+06h 07m 19s} (1950)
GRB_DEC:         -13.295d {-13d 17' 42"} (J2000),
                 -13.299d {-13d 17' 54"} (current),
                 -13.285d {-13d 17' 05"} (1950)
GRB_DATE:        16516 TJD;   224 DOY;   13/08/12
GRB_TIME:        80572.58 SOD {22:22:52.58} UT
TRIGGER_INDEX:   120
GRB_PHI:           9.23 [deg]
GRB_THETA:        29.44 [deg]
DELTA_TIME:      52.00 [sec]
TRIGGER_DUR:     0.256 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     26.09 [sigma]
IMAGE_SIGNIF:    11.67 [sigma]
LC_URL:          sw00566228000msb.lc
SUN_POSTN:       142.76d {+09h 31m 03s}  +14.70d {+14d 41' 59"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.81d {+13h 55m 14s}  -12.68d {-12d 41' 02"}
MOON_DIST:       111.68 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       92.92,-36.71 [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 = 156.28,-20.34 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 12 Aug 13 22:28:42 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     566228,   Seg_Num: 0
GRB_RA:           92.3943d {+06h 09m 34.63s} (J2000),
                  92.5508d {+06h 10m 12.20s} (current),
                  91.8195d {+06h 07m 16.67s} (1950)
GRB_DEC:         -13.2888d {-13d 17' 19.6"} (J2000),
                 -13.2921d {-13d 17' 31.4"} (current),
                 -13.2786d {-13d 16' 42.8"} (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:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80667.00 SOD {22:24:27.00} UT,   94.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       142.76d {+09h 31m 03s}  +14.70d {+14d 41' 57"}
SUN_DIST:         57.04 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.83d {+13h 55m 19s}  -12.69d {-12d 41' 19"}
MOON_DIST:       111.71 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.31,-15.20 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.91,-36.70 [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:     Mon 12 Aug 13 22:32:37 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
POINT_ROLL:      62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80711.54 SOD {22:25:11.54} UT,   139.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.138
N_STARS:         190
X_OFFSET:        145 [pixels]
Y_OFFSET:        350 [pixels]
X_MAX:           1584 [pixels]
Y_MAX:           1789 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00566228000msufc0138.fits
SUN_POSTN:       142.77d {+09h 31m 04s}  +14.70d {+14d 41' 54"}
SUN_DIST:         57.02 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.86d {+13h 55m 27s}  -12.70d {-12d 41' 54"}
MOON_DIST:       111.72 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 12 Aug 13 22:33:04 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
POINT_ROLL:      62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80711.54 SOD {22:25:11.54} UT,   139.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.138
N_STARS:         190
X_OFFSET:        145 [pixels]
Y_OFFSET:        350 [pixels]
X_MAX:           1584 [pixels]
Y_MAX:           1789 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00566228000msufc0138.fits
SUN_POSTN:       142.77d {+09h 31m 04s}  +14.70d {+14d 41' 54"}
SUN_DIST:         57.02 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.87d {+13h 55m 28s}  -12.70d {-12d 41' 58"}
MOON_DIST:       111.72 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [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:     Mon 12 Aug 13 22:33:09 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     566228,   Seg_Num: 0
GRB_RA:           92.3954d {+06h 09m 34.89s} (J2000),
                  92.5519d {+06h 10m 12.46s} (current),
                  91.8206d {+06h 07m 16.93s} (1950)
GRB_DEC:         -13.2874d {-13d 17' 14.6"} (J2000),
                 -13.2907d {-13d 17' 26.4"} (current),
                 -13.2772d {-13d 16' 37.7"} (1950)
GRB_ERROR:       2.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80667.00 SOD {22:24:27.00} UT,   94.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       142.77d {+09h 31m 04s}  +14.70d {+14d 41' 54"}
SUN_DIST:         57.04 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.87d {+13h 55m 29s}  -12.70d {-12d 41' 58"}
MOON_DIST:       111.74 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.31,-15.20 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.91,-36.70 [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:     Mon 12 Aug 13 22:34:02 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
ROLL:            62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80711.54 SOD {22:25:11.54} UT,   139.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     398039122
X_OFFSET:        704 [pixels]
Y_OFFSET:        909 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       864
Y_GRB_POS:       1069
BINNING_INDEX:   1
IM_URL:          sw00566228000msuni0149.fits
SUN_POSTN:       142.77d {+09h 31m 04s}  +14.70d {+14d 41' 53"}
SUN_DIST:         57.02 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.88d {+13h 55m 31s}  -12.70d {-12d 42' 06"}
MOON_DIST:       111.73 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [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:     Mon 12 Aug 13 22:34:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
ROLL:            62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  80711.54 SOD {22:25:11.54} UT,   139.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     398039122
X_OFFSET:        704 [pixels]
Y_OFFSET:        909 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       864
Y_GRB_POS:       1069
BINNING_INDEX:   1
IM_URL:          sw00566228000msuni0149.fits
SUN_POSTN:       142.77d {+09h 31m 04s}  +14.70d {+14d 41' 53"}
SUN_DIST:         57.02 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.88d {+13h 55m 32s}  -12.70d {-12d 42' 10"}
MOON_DIST:       111.73 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [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 #15088
V. D'Elia (ASDC), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), V. Mangano (PSU), C. B. Markwardt (NASA/GSFC) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 22:22:52 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130812A (trigger=566228). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 92.402, -13.295 which is
```
   RA(J2000)  =  06h 09m 37s
   Dec(J2000) = -13d 17' 42"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a total duration of about 10 sec. The peak count rate was ~4500 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 22:24:09.6 UT, 77.0 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 92.3955, -13.2875 which is equivalent to:
```
   RA(J2000)  = 06h 09m 34.92s
   Dec(J2000) = -13d 17' 15.1"
```
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 35 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 in excess of the Galactic value (1.51 x 10^21 cm^-2, Kalberla et al. 2005), with an excess column of 1.5 (+1.52/-1.37) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 138 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 19.2 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 18.0 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.23.
Burst Advocate for this burst is V. D'Elia (delia AT asdc.asi.it). 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:     Mon 12 Aug 13 22:43:24 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
POINT_ROLL:      62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  81443.14 SOD {22:37:23.14} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.370
N_STARS:         190
X_OFFSET:        145 [pixels]
Y_OFFSET:        350 [pixels]
X_MAX:           1584 [pixels]
Y_MAX:           1789 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00566228000msufc0870.fits
SUN_POSTN:       142.77d {+09h 31m 05s}  +14.70d {+14d 41' 46"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.96d {+13h 55m 51s}  -12.72d {-12d 43' 28"}
MOON_DIST:       111.80 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 12 Aug 13 22:43:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
ROLL:            62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  81443.14 SOD {22:37:23.14} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     398039854
X_OFFSET:        704 [pixels]
Y_OFFSET:        909 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       864
Y_GRB_POS:       1069
BINNING_INDEX:   1
IM_URL:          sw00566228000msuni0881.fits
SUN_POSTN:       142.77d {+09h 31m 05s}  +14.70d {+14d 41' 46"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.96d {+13h 55m 52s}  -12.73d {-12d 43' 30"}
MOON_DIST:       111.80 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [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:     Mon 12 Aug 13 22:43:31 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
ROLL:            62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  81443.14 SOD {22:37:23.14} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     398039854
X_OFFSET:        704 [pixels]
Y_OFFSET:        909 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       864
Y_GRB_POS:       1069
BINNING_INDEX:   1
IM_URL:          sw00566228000msuni0881.fits
SUN_POSTN:       142.77d {+09h 31m 05s}  +14.70d {+14d 41' 46"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.96d {+13h 55m 52s}  -12.73d {-12d 43' 29"}
MOON_DIST:       111.80 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [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:     Mon 12 Aug 13 22:43:27 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     566228,   Seg_Num: 0
POINT_RA:         92.415d {+06h 09m 40s} (J2000)
POINT_DEC:       -13.291d {-13d 17' 26"} (J2000)
POINT_ROLL:      62.443d
IMG_START_DATE:  16516 TJD;   224 DOY;   13/08/12
IMG_START_TIME:  81443.14 SOD {22:37:23.14} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.370
N_STARS:         190
X_OFFSET:        145 [pixels]
Y_OFFSET:        350 [pixels]
X_MAX:           1584 [pixels]
Y_MAX:           1789 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00566228000msufc0870.fits
SUN_POSTN:       142.77d {+09h 31m 05s}  +14.70d {+14d 41' 46"}
SUN_DIST:         57.03 [deg]   Sun_angle= 3.3 [hr] (West of Sun)
MOON_POSTN:      208.96d {+13h 55m 51s}  -12.72d {-12d 43' 29"}
MOON_DIST:       111.80 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      220.32,-15.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.93,-36.71 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN Circular #15089
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 2469 s of XRT Photon Counting mode data and 5 UVOT images for GRB 130812A, 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 = 92.39590, -13.28816 which is equivalent to:
```
RA (J2000): 06h 09m 35.02s
Dec (J2000): -13d 17' 17.4"
```
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, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #15090
P.A. Evans (U. Leicester), B.P. Gompertz (U. Leicester), P. D'Avanzo (INAF-OAB), A. Maselli (INAF-IASFPA), V. Mangano (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), J.P. Osborne (U. Leicester) and V. D'Elia report on behalf of the Swift-XRT team:
We have analysed 8.9 ks of XRT data for GRB 130812A (D'Elia et al. GCN Circ. 15088), from 62 s to 22.3 ks after the BAT trigger. The data comprise 8 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 15089).
The light curve can be modelled with a power-law decay with a decay index of alpha=0.86 (+/-0.03).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.04 (+0.17, -0.16). The best-fitting absorption column is 3.0 (+/-0.6) x 10^21 cm^-2, in excess of the Galactic value of 1.5 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.1 x 10^-11 (6.6 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     3.0 (+/-0.6) x 10^21 cm^-2
Galactic foreground: 1.5 x 10^21 cm^-2
Excess significance: 4.3 sigma
Photon index:	     2.04 (+0.17, -0.16)
```
If the light curve continues to decay with a power-law decay index of 0.86, the count rate at T+24 hours will be 7.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.9 x 10^-13 (4.6 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00566228.
This circular is an official product of the Swift-XRT team.
GCN Circular #15091
K. Varela (MPE Garching), D.A. Kann (TLS Tautenburg), J. Greiner (MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 130812A (Swift trigger 566228; D'Elia et al. 2013, GCN #15088) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG/ESO telescope at La Silla Observatory (Chile).
Observations started at 10:13 UT on 13 Aug. 2013, 11.8 hrs after the GRB trigger. They were performed at an average seeing of 2.5" and at an average airmass of 1.4.
In 212 sec exposure in g'r'i'z' and 360 sec exposure in JHK we do not detect a source within the 1.8 arcsec Swift-XRT error circle reported by Evans et al. (2013; GCN #15089) down to (all in the AB system)
g' > 22.4,
r' > 22.6,
i' > 21.9,
z' > 21.7,
J > 20.3,
H > 19.4 and
K > 18.8
The given limits are derived based on calibrating the images against GROND zeropoints and 2MASS field stars and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.23 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #15092
D. M. Palmer (LANL), 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), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-144 to T+431 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130812A (trigger #566228) (D'Elia, et al., GCN Circ. 15088). The BAT ground-calculated position is RA, Dec = 92.387, -13.285 deg which is
```
  RA(J2000)  =  06h 09m 32.8s 
  Dec(J2000) = -13d 17' 06.6" 
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 75%.
The mask-weighted light curve shows multiple spikes peaking at T0, T0+4 sec and T0+7 sec. T90 (15-350 keV) is 7.6 +- 0.5 sec (estimated error including systematics).
The time-averaged spectrum from T-0.3 to T+8.5 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.52 +- 0.11. The fluence in the 15-150 keV band is 5.9 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.14 sec in the 15-150 keV band is 2.8 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis will be available at http://gcn.gsfc.nasa.gov/notices_s/566228/BA/
GCN Circular #15093
A. A. Breeveld (UCL-MSSL) and V. D'Elia (ASDC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 130812A 139 s after the BAT trigger (D'Elia et al., GCN Circ. 15088). No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 15089) 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

u_FC               139          389          246         >20.3
v                  445        12868         1191         >20.5
b                  394        11236         1459         >21.7
u                  139         7030          884         >20.8
w1                 494         6825          491         >20.5
m2                 469         6619          452         >20.3
w2                 421        12142         1376         >21.3
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.23 in the direction of the burst (Schlegel et al. 1998).
GCN Report 453.1
GCN_Report 453.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_453_1.pdf by V. D Elia at ASDC titled: "Swift Observations of GRB 130812A"

Back to JG's homepage

Jochen Greiner, last update: 26-Apr-2014 [Disclaimer]