Gamma-ray Burst 160712A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 19:54:01 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.149d {+20h 16m 36s} (J2000),
                 304.400d {+20h 17m 36s} (current),
                 303.391d {+20h 13m 34s} (1950)
GRB_DEC:         -26.981d {-26d 58' 52"} (J2000),
                 -26.929d {-26d 55' 45"} (current),
                 -27.136d {-27d 08' 09"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4407 [cnts]    Image_Peak=144 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   156     E_range: 50-350 keV
BKG_INTEN:       17278 [cnts]
BKG_TIME:        71599.44 SOD {19:53:19.44} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17581 TJD;   194 DOY;   16/07/12
GRB_TIME:        71616.02 SOD {19:53:36.02} UT
GRB_PHI:          83.06 [deg]
GRB_THETA:        34.12 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     39.56 [sigma]
IMAGE_SIGNIF:    7.67 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +3  -2  +0  +0 +97  +0 
SUN_POSTN:       112.57d {+07h 30m 18s}  +21.82d {+21d 48' 55"}
SUN_DIST:        168.08 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      208.78d {+13h 55m 08s}   -7.90d {-07d 53' 56"}
MOON_DIST:        91.39 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.78,-29.66 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      300.27, -7.06 [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 = 152.28,12.27 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 19:57:08 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.149d {+20h 16m 36s} (J2000),
                 304.400d {+20h 17m 36s} (current),
                 303.391d {+20h 13m 34s} (1950)
GRB_DEC:         -26.981d {-26d 58' 52"} (J2000),
                 -26.929d {-26d 55' 45"} (current),
                 -27.136d {-27d 08' 09"} (1950)
GRB_DATE:        17581 TJD;   194 DOY;   16/07/12
GRB_TIME:        71616.02 SOD {19:53:36.02} UT
TRIGGER_INDEX:   156
GRB_PHI:          83.06 [deg]
GRB_THETA:        34.12 [deg]
DELTA_TIME:      -56.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     39.56 [sigma]
IMAGE_SIGNIF:    7.67 [sigma]
LC_URL:          sw00704155000msb.lc
SUN_POSTN:       112.58d {+07h 30m 18s}  +21.82d {+21d 48' 54"}
SUN_DIST:        168.09 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      208.81d {+13h 55m 14s}   -7.91d {-07d 54' 23"}
MOON_DIST:        91.36 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.78,-29.66 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      300.27, -7.06 [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 = 152.28,12.27 [deg].

GCN Circular #19684
L. M. Z. Hagen (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), S. B. Cenko (GSFC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 19:53:36 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160712A (trigger=704155). Swift did not slew immediately due to an observational constraint. The BAT on-board calculated location is RA, Dec 304.149, -26.981 which is
```
   RA(J2000) = 20h 16m 36s
   Dec(J2000) = -26d 58' 52"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a long burst with a duration of ~ 20 s and containing a short spike. The peak count rate was ~4500 counts/sec (15-350 keV), at ~0 sec after the trigger.
Due to an observing constraint, Swift will not slew until T0+47.3 minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is L. M. Z. Hagen (lea.zernow.hagen AT gmail.com). 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 #19685
D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory
E. Gorbovskoy, V. Lipunov, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Senik Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, A.Gabovich, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
Ricardo Podesta, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA)
Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in SAAO was pointed to the GRB160712.83 26 sec after notice time and 48 sec after trigger time at 2016-07-12 19:54:28 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (ra=20 16 35 dec=-26 58 52 r=0.050000). The 5-sigma upper limit has been about 16.7 mag The message may be cited.
The message may be cited.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 20:48:39 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.0167d {+20h 16m 04.00s} (J2000),
                 304.2671d {+20h 17m 04.10s} (current),
                 303.2581d {+20h 13m 01.94s} (1950)
GRB_DEC:         -26.9138d {-26d 54' 49.6"} (J2000),
                 -26.8622d {-26d 51' 43.7"} (current),
                 -27.0680d {-27d 04' 04.8"} (1950)
GRB_ERROR:       4.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.08e-09 [erg/cm2/sec]
GRB_SIGNIF:      4.89 [sigma]
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  74872.73 SOD {20:47:52.73} UT,   3256.7 [sec] since BAT Trigger Time
TAM[0-3]:        327.69 237.21 261.66 243.55
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       112.61d {+07h 30m 27s}  +21.81d {+21d 48' 35"}
SUN_DIST:        168.25 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.22d {+13h 56m 52s}   -8.03d {-08d 01' 44"}
MOON_DIST:        90.84 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.81,-29.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      300.17, -6.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 8.16 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 .  
COMMENTS:        WARNING: The centroided position is more than 100 rows or columns from the center of the FOV.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 20:48:50 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.0167d {+20h 16m 04.0s} (J2000),
                 304.2671d {+20h 17m 04.1s} (current),
                 303.2581d {+20h 13m 01.9s} (1950)
GRB_DEC:         -26.9138d {-26d 54' 49.6"} (J2000),
                 -26.8622d {-26d 51' 43.7"} (current),
                 -27.0680d {-27d 04' 04.8"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       24 [cnts]
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  74872.73 SOD {20:47:52.73} UT,   3256.7 [sec] since BAT Trigger Time
CENTROID_X:      453.18,  raw= 453  [pixels]
CENTROID_Y:      302.20,  raw= 302  [pixels]
ROLL:            113.66 [deg]
GAIN:            16
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   10.39
GRB_POS_XRT_Z:   348.61
IMAGE_URL:       sw00704155000msxps_rw.img
SUN_POSTN:       112.61d {+07h 30m 27s}  +21.81d {+21d 48' 35"}
SUN_DIST:        168.25 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.22d {+13h 56m 52s}   -8.03d {-08d 01' 45"}
MOON_DIST:        90.84 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.81,-29.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      300.17, -6.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.  
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 .  
COMMENTS:        WARNING: The centroided position is more than 100 rows or columns from the center of the FOV.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 20:48:57 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.0167d {+20h 16m 04.0s} (J2000),
                 304.2671d {+20h 17m 04.1s} (current),
                 303.2581d {+20h 13m 01.9s} (1950)
GRB_DEC:         -26.9138d {-26d 54' 49.6"} (J2000),
                 -26.8622d {-26d 51' 43.7"} (current),
                 -27.0680d {-27d 04' 04.8"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       24 [cnts]
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  74872.73 SOD {20:47:52.73} UT,   3256.7 [sec] since BAT Trigger Time
CENTROID_X:      453.18,  raw= 453  [pixels]
CENTROID_Y:      302.20,  raw= 302  [pixels]
ROLL:            113.66 [deg]
GAIN:            16
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   10.39
GRB_POS_XRT_Z:   348.61
IMAGE_URL:       sw00704155000msxps_rw.img
SUN_POSTN:       112.61d {+07h 30m 27s}  +21.81d {+21d 48' 35"}
SUN_DIST:        168.25 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.22d {+13h 56m 52s}   -8.03d {-08d 01' 46"}
MOON_DIST:        90.84 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.81,-29.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      300.17, -6.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.  
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:     Tue 12 Jul 16 21:03:11 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     704155,   Seg_Num: 0
POINT_RA:        304.114d {+20h 16m 27s} (J2000)
POINT_DEC:       -26.955d {-26d 57' 16"} (J2000)
POINT_ROLL:      113.660d
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  75614.28 SOD {21:00:14.28} UT,   3998.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.866
N_STARS:         79
X_OFFSET:        767 [pixels]
Y_OFFSET:        493 [pixels]
X_MAX:           1726 [pixels]
Y_MAX:           1452 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00704155000msufc3998.fits
SUN_POSTN:       112.62d {+07h 30m 29s}  +21.81d {+21d 48' 30"}
SUN_DIST:        168.16 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.33d {+13h 57m 19s}   -8.06d {-08d 03' 48"}
MOON_DIST:        90.80 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.80,-29.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      300.25, -7.03 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Jul 16 21:03:35 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     704155,   Seg_Num: 0
POINT_RA:        304.114d {+20h 16m 27s} (J2000)
POINT_DEC:       -26.955d {-26d 57' 16"} (J2000)
POINT_ROLL:      113.660d
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  75614.28 SOD {21:00:14.28} UT,   3998.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.866
N_STARS:         79
X_OFFSET:        767 [pixels]
Y_OFFSET:        493 [pixels]
X_MAX:           1726 [pixels]
Y_MAX:           1452 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00704155000msufc3998.fits
SUN_POSTN:       112.62d {+07h 30m 29s}  +21.81d {+21d 48' 30"}
SUN_DIST:        168.16 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.33d {+13h 57m 20s}   -8.06d {-08d 03' 52"}
MOON_DIST:        90.80 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.80,-29.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      300.25, -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:     Tue 12 Jul 16 21:03:42 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     704155,   Seg_Num: 0
GRB_RA:          304.1598d {+20h 16m 38.35s} (J2000),
                 304.4102d {+20h 17m 38.45s} (current),
                 303.4012d {+20h 13m 36.28s} (1950)
GRB_DEC:         -26.9584d {-26d 57' 30.2"} (J2000),
                 -26.9066d {-26d 54' 23.6"} (current),
                 -27.1132d {-27d 06' 47.5"} (1950)
GRB_ERROR:       3.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  75586.00 SOD {20:59:46.00} UT,   3970.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       112.62d {+07h 30m 29s}  +21.81d {+21d 48' 30"}
SUN_DIST:        168.12 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.34d {+13h 57m 20s}   -8.06d {-08d 03' 53"}
MOON_DIST:        90.84 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.81,-29.66 [deg] galactic lon,lat of the burst
ECL_COORDS:      300.28, -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.  
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:     Tue 12 Jul 16 21:04:51 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     704155,   Seg_Num: 0
POINT_RA:        304.114d {+20h 16m 27s} (J2000)
POINT_DEC:       -26.955d {-26d 57' 16"} (J2000)
ROLL:            113.660d
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  75614.28 SOD {21:00:14.28} UT,   3998.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     490050030
X_OFFSET:        1086 [pixels]
Y_OFFSET:        812 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1246
Y_GRB_POS:       972
BINNING_INDEX:   1
IM_URL:          sw00704155000msuni4015.fits
SUN_POSTN:       112.62d {+07h 30m 30s}  +21.81d {+21d 48' 29"}
SUN_DIST:        168.16 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.34d {+13h 57m 23s}   -8.07d {-08d 04' 02"}
MOON_DIST:        90.79 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.80,-29.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      300.25, -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:     Tue 12 Jul 16 21:05:20 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     704155,   Seg_Num: 0
POINT_RA:        304.114d {+20h 16m 27s} (J2000)
POINT_DEC:       -26.955d {-26d 57' 16"} (J2000)
ROLL:            113.660d
IMG_START_DATE:  17581 TJD;   194 DOY;   16/07/12
IMG_START_TIME:  75614.28 SOD {21:00:14.28} UT,   3998.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     490050030
X_OFFSET:        1086 [pixels]
Y_OFFSET:        812 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1246
Y_GRB_POS:       972
BINNING_INDEX:   1
IM_URL:          sw00704155000msuni4015.fits
SUN_POSTN:       112.62d {+07h 30m 30s}  +21.81d {+21d 48' 29"}
SUN_DIST:        168.16 [deg]   Sun_angle= 11.2 [hr] (West of Sun)
MOON_POSTN:      209.35d {+13h 57m 24s}   -8.07d {-08d 04' 06"}
MOON_DIST:        90.78 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:       15.80,-29.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      300.25, -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 #19686
J.A. Kennea (PSU), G. Cusumano (INAF-IASF PA), M. Perri (ASDC), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester) and D.N. Burrows (PSU) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 160712A at 20:47:52.7 UT, 3256.7 seconds after the BAT trigger. The position determined from promptly downlinked data differs significantly from the on-board position, suggesting that the XRT may have centroided on a cosmic ray; the initial XRT position notice should be treated with caution. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 304.1600, -26.9582 which is equivalent to:
```
   RA(J2000)  = 20h 16m 38.40s
   Dec(J2000) = -26d 57' 29.4"
```
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 89 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 (8.30 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.7 (+2.97/-2.55) x 10^21 cm^-2 (90% confidence).
GCN Circular #19687
L. M. Z. Hagen (PSU) reports on behalf of the Swift/UVOT team:
UVOT took a finding chart exposure of 150 seconds with the White filter starting 3998 seconds after the BAT trigger (Hagen et al., GCN Circ. 19684). 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 (Kennea et al., GCN Circ. 19686). 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 expected extinction corresponding to E(B-V) of 0.08.
GCN Circular #19690
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 1053 s of XRT Photon Counting mode data and 3 UVOT images for GRB 160712A, 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 = 304.15987, -26.95819 which is equivalent to:
```
RA (J2000): 20h 16m 38.37s
Dec (J2000): -26d 57' 29.5"
```
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 #19691
A. Trotter, J. Haislip, D. Reichart, A. Verveer, T. Spuck, J. Moore, N. Frank, M. Maples, D. Dutton, R. Gao, R. Joyner, J. Martin, M. Paggen, J. A. Crain, K. Ivarsen, A. LaCluyze, M. Nysewander, B. Barlow, J. LaCluyze, L. Lanier, D. Moffett, B. Tobias, G. Bennett, J. Da Rocha, M. Dryzer, D. Dutton, J. Elliott, C. Ferguson, R. J. Hegedus, E. Lutz, B. McCormack, T. Melo, K. Otto, R. Pierce, S. Simon, E. Smith, J. Taylor, M. Tierney, D. Varvir, and A. Vasquez Soto report:
Skynet observed the Swift BAT/XRT localization of GRB 160712A (Hagen et al., GCN 19684, Swift trigger=704155) with the 14" R-COP telescope at Perth Observatory, Australia. Starting at 2016-07-12 19:58 UT and continuing until 20:30 UT (t=4.3m-31.4m post-trigger), Skynet took a total of 17 20-160s exposures in the B, V, R, and I bands. We stacked subsets of these images to maximize the S/N ratio, and detected no optical source in any band at the XRT position. Our 3-sigma limiting magnitudes are:
```
====================
tmid  fil  limit
====================
23m   B   >16.7
26m   V   >17.2
23m   R   >17.7
29m   I   >16.9
====================
```
Limiting magnitudes are in the Vega System, calibrated to 5 APASS stars in the field. Magnitudes have not been corrected for line-of-sight Milky Way dust extinction, with expected E(B-V)=0.07 (Schlafly & Finkbeiner 2011).
No further Skynet observations are scheduled.
GCN Circular #19692
S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Maselli (INAF-IASFPA), L.M. McCauley (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU) and L. M. Z. Hagen (PSU) report on behalf of the Swift-XRT team:
We have analysed 3.8 ks of XRT data for GRB 160712A (Hagen et al. GCN Circ. 19684), from 4.0 ks to 17.2 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 19690).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.51 (+0.25, -0.22).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.91 (+0.28, -0.26). The best-fitting absorption column is 2.8 (+1.3, -1.1) x 10^21 cm^-2, in excess of the Galactic value of 8.3 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.8 x 10^-11 (5.3 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     2.8 (+1.3, -1.1) x 10^21 cm^-2
Galactic foreground: 8.3 x 10^20 cm^-2
Excess significance: 3.0 sigma
Photon index:	     1.91 (+0.28, -0.26)
```
If the light curve continues to decay with a power-law decay index of 1.51, the count rate at T+24 hours will be 2.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.9 x 10^-14 (1.1 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/00704155.
This circular is an official product of the Swift-XRT team.
GCN Circular #19693
T. Kruehler and J. Greiner (all MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 160712A (Swift trigger 704155; Hagen et al., GCN #19684) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at the ESO La Silla Observatory (Chile).
Observations started at 03:18:21 UT on 2016-07-13, 7.4 hr after the GRB trigger. They were performed at an average seeing of 2=E2=80=9D.2, at an average airmass of 1.1, and severely affected by passing clouds.
We found a single source sightly outside of the XRT errorcircle at:
```
RA (J2000.0) =3D 20:16:38.50
Dec. (J2000.0) =3D -26:57:30.7
```
with an uncertainty of 0".5 in each coordinate. The distance to the center of the XRT error circle (90% confidence radius 1".5 arcsec) is 2".2.
Based on images with 24.2 min of total exposure in g'r'i'z' and 24.0 min in JHK at a mid-time of 03:57:19 UT on 2016-07-13, we derive the following preliminary magnitudes and upper limits (all in AB system):
```
g > 23.3 mag
r = 22.9 +- 0.3 mag
i = 21.7 +- 0.3 mag
z = 21.4 +- 0.3 mag
J = 20.5 +- 0.2 mag
H = 20.2 +- 0.2 mag
K = 20.0 +- 0.3 mag
```
Given magnitudes are calibrated against USNO as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) =3D 0.065 mag in the direction of the burst (Schlafly & Finkbeiner 2011).
No statement about variability can be made at this point. Given its position somewhat outside of the XRT error circle, it is uncertain whether this source is related to GRB 160712A.
GCN Circular #19694
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report:
The long GRB 160712A (Swift/BAT observation: Hagen et al., GCN 19684) triggered Konus-Wind at T0=3D71621.420 s UT (19:53:41.420).
The light curve statrs with a short spike followed by a gradually decaying emission. The total duration of the burst is ~25 s. The emission is seen up to ~4 MeV.
As observed by Konus-Wind, the burst had a fluence of (6.5 =B1 2.0)x10^-6 erg/cm2 and a 64-ms peak energy flux, measured from T0+0.128, of (2.7 =B1 0.8)x10^-6 erg/cm2 (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum (measured from T0 to T0+16.640 s) is best fit in the 20 keV - 4 MeV range by a cutoff power-law (CPL) function with the following model parameters: the photon index alpha =3D -0.17(-0.57,+0.87), and the peak energy Ep =3D 460(-117,+204) keV, chi2 =3D 72/73 dof. Fitting this spectrum with the GRB (Band) function yields the same alpha and Ep with only an upper limit on beta of -2.3, chi2 =3D 72/72 dof.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB160712_T71621/
All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary.
GCN Circular #19695
GRB 160712A: RATIR Optical and NIR Observations
Eleonora Troja (GSFC), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jos=E9 A. de Diego (UNAM), Leonid Georgiev (UNAM), Jes=FAs Gonz=E1lez (UNAM), Carlos Rom=E1n-Z=FA=F1iga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report:
We observed the field of GRB 160712A (Hagen, et al., GCN 19684) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astron=F3mico Nacional on Sierra San Pedro M=E1rtir from 2016/07 13.21 to 2016/07 13.42 UTC (9.05 to 14.30 hours after the BAT trigger), obtaining a total of 3.56 hours exposure in the r and i bands and 1.45 hours exposure in the Z, Y, J, and H bands.
We detect a source slightly outside of the XRT error circle (Beardmore, et al., GCN 19690), and consistent with the GROND position (Kruehler, et al., GCN 19693). In comparison with the USNO-B1 and 2MASS catalogs, we obtain the following detections:
```
   r    22.77 +/- 0.08
   i    21.55 +/- 0.03
   Z    20.93 +/- 0.05
   Y    20.44 +/- 0.05
   J    20.27 +/- 0.06
   H    20.15 +/- 0.08
```
These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. Further observations to determine whether the source is fading are planned.
We thank the staff of the Observatorio Astron=F3mico Nacional in San Pedro M=E1rtir.
GCN Circular #19696
L. M. Z. Hagen (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160712A 3998 s after the BAT trigger (Hagen et al., GCN Circ. 19684). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 19690) or the possible optical afterglow candidate (Kruehler et al., GCN Circ. 19693; Troja et al., GCN Circ. 19695) 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 exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white             3998         4148          147        >20.47
v                 4154         4354          196        >19.04
b                 4974         5027           52        >19.17
u                 4769         4969          196        >19.66
uvw1              4564         4764          196        >19.58
uvm2              4359         4559          196        >19.52
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.08 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19702
T. Kruehler and J. Greiner (all MPE Garching) report on behalf of the GROND team:
We re-observed the field of GRB 160712A (Swift trigger 704155; Hagen et al., GCN #19684) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at the ESO La Silla Observatory (Chile).
Observations started at 04:38:43 UT on 2016-07-14, 32.8 hr after the GRB trigger, and consisted of multiple exposures with a total integration time of around 80 minutes. The average seeing and airmass were 2.0 and 1.0, respectively.
Within photometric errors, no variability is detected with respect to our earlier observations (GCN 19693, see also Troja et al. GCN 19695). The source is hence unlikely to be the afterglow of GRB 160712A.
GCN Circular #19713
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160712A (trigger #704155) (Hagen, et al., GCN Circ. 19684). The BAT ground-calculated position is RA, Dec = 304.166, -26.965 deg which is
```
  RA(J2000)  =  20h 16m 39.9s
  Dec(J2000) = -26d 57' 52.8"
```
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 24%.
The mask-weighted lightcurve shows the burst starting at ~T-5 sec, with a spike at ~T0 sec, extending past T+95 sec where the data ends when the burst position moves out of the BAT FOV due to a slew.
The time-averaged spectrum from T-8.60 to T+45.46 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.18 +- 0.13. The fluence in the 15-150 keV band is 2.6 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band is 2.4 +- 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/704155/BA/

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Jochen Greiner, last update: 14-Jul-2016 [Disclaimer]