Gamma-ray Burst 210702A

(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 02 Jul 21 19:20:38 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1058804,   Seg_Num: 0
GRB_RA:          168.570d {+11h 14m 17s} (J2000),
                 168.828d {+11h 15m 19s} (current),
                 167.971d {+11h 11m 53s} (1950)
GRB_DEC:         -36.741d {-36d 44' 28"} (J2000),
                 -36.859d {-36d 51' 31"} (current),
                 -36.469d {-36d 28' 07"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       9607 [cnts]    Image_Peak=128 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   155     E_range: 50-350 keV
BKG_INTEN:       27845 [cnts]
BKG_TIME:        68820.69 SOD {19:07:00.69} UT
BKG_DUR:         8 [sec]
GRB_DATE:        19397 TJD;   183 DOY;   21/07/02
GRB_TIME:        68833.69 SOD {19:07:13.69} UT
GRB_PHI:         -157.89 [deg]
GRB_THETA:        60.28 [deg]
SOLN_STATUS:     0x20000083
RATE_SIGNIF:     95.06 [sigma]
IMAGE_SIGNIF:    6.99 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +3  -3  +0  +0  -6  +0 
SUN_POSTN:       102.09d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.74 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:       21.42d {+01h 25m 41s}   +4.69d {+04d 41' 30"}
MOON_DIST:       136.13 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.08, 22.17 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      186.70,-37.74 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This Notice was delayed by more than 60 sec past the end of the trigger integration interval;  
COMMENTS:        probably due to it occurring during a Malindi downlink session.  
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:        Since the IMAGE_SIGNIF is less than 7 sigma, this is a questionable detection.  
COMMENTS:        This trigger occurred at longitude,latitude = 10.86,-8.32 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(7.0<100sec) coincident with the CALET_GBM event (trignum=1309287819).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:21:11 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     1058804,   Seg_Num: 0
GRB_RA:          168.5813d {+11h 14m 19.51s} (J2000),
                 168.8393d {+11h 15m 21.42s} (current),
                 167.9828d {+11h 11m 55.86s} (1950)
GRB_DEC:         -36.7474d {-36d 44' 50.6"} (J2000),
                 -36.8648d {-36d 51' 53.2"} (current),
                 -36.4748d {-36d 28' 29.2"} (1950)
GRB_ERROR:       4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-08 [erg/cm2/sec]
GRB_SIGNIF:      15.09 [sigma]
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68929.20 SOD {19:08:49.20} UT,   95.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.66 237.18 261.71 243.48
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       102.09d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.75 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 42s}   +4.69d {+04d 41' 37"}
MOON_DIST:       136.13 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.09, 22.16 [deg] galactic lon,lat of the burst
ECL_COORDS:      186.71,-37.74 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.66 arcmin from the BAT position.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:21:20 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
GRB_RA:          168.5813d {+11h 14m 19.5s} (J2000),
                 168.8393d {+11h 15m 21.4s} (current),
                 167.9828d {+11h 11m 55.8s} (1950)
GRB_DEC:         -36.7474d {-36d 44' 50.6"} (J2000),
                 -36.8648d {-36d 51' 53.2"} (current),
                 -36.4748d {-36d 28' 29.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       228 [cnts]
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68929.20 SOD {19:08:49.20} UT,   95.5 [sec] since BAT Trigger Time
CENTROID_X:      286.40,  raw= 286  [pixels]
CENTROID_Y:      322.96,  raw= 323  [pixels]
ROLL:            302.21 [deg]
GAIN:            4
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   58.61
GRB_POS_XRT_Z:   -49.48
IMAGE_URL:       sw01058804000msxps_rw.img
SUN_POSTN:       102.09d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.75 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 42s}   +4.69d {+04d 41' 39"}
MOON_DIST:       136.13 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.09, 22.16 [deg] galactic lon,lat of the burst
ECL_COORDS:      186.71,-37.74 [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 .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:21:22 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
GRB_RA:          168.5813d {+11h 14m 19.5s} (J2000),
                 168.8393d {+11h 15m 21.4s} (current),
                 167.9828d {+11h 11m 55.8s} (1950)
GRB_DEC:         -36.7474d {-36d 44' 50.6"} (J2000),
                 -36.8648d {-36d 51' 53.2"} (current),
                 -36.4748d {-36d 28' 29.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       228 [cnts]
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68929.20 SOD {19:08:49.20} UT,   95.5 [sec] since BAT Trigger Time
CENTROID_X:      286.40,  raw= 286  [pixels]
CENTROID_Y:      322.96,  raw= 323  [pixels]
ROLL:            302.21 [deg]
GAIN:            4
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   58.61
GRB_POS_XRT_Z:   -49.48
IMAGE_URL:       sw01058804000msxps_rw.img
SUN_POSTN:       102.09d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.75 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 42s}   +4.69d {+04d 41' 40"}
MOON_DIST:       136.13 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.09, 22.16 [deg] galactic lon,lat of the burst
ECL_COORDS:      186.71,-37.74 [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:     Fri 02 Jul 21 19:21:43 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1058804,   Seg_Num: 0
GRB_RA:          168.570d {+11h 14m 17s} (J2000),
                 168.828d {+11h 15m 19s} (current),
                 167.971d {+11h 11m 53s} (1950)
GRB_DEC:         -36.741d {-36d 44' 28"} (J2000),
                 -36.859d {-36d 51' 31"} (current),
                 -36.469d {-36d 28' 07"} (1950)
GRB_DATE:        19397 TJD;   183 DOY;   21/07/02
GRB_TIME:        68833.69 SOD {19:07:13.69} UT
TRIGGER_INDEX:   155
GRB_PHI:         -157.89 [deg]
GRB_THETA:        60.28 [deg]
DELTA_TIME:      -18.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x83
RATE_SIGNIF:     95.06 [sigma]
IMAGE_SIGNIF:    6.99 [sigma]
LC_URL:          sw01058804000msb.lc
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.74 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 43s}   +4.70d {+04d 41' 44"}
MOON_DIST:       136.13 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.08, 22.17 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      186.70,-37.74 [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:        Since the IMAGE_SIGNIF is less than 7 sigma, this is a questionable detection.  
COMMENTS:        This trigger occurred at longitude,latitude = 10.86,-8.32 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:22:02 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.606d {+11h 14m 25s} (J2000)
POINT_DEC:       -36.741d {-36d 44' 28"} (J2000)
POINT_ROLL:      302.210d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68937.56 SOD {19:08:57.56} UT,   103.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.074
N_STARS:         151
X_OFFSET:        568 [pixels]
Y_OFFSET:        352 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1311 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw01058804000msufc0103.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 44s}   +4.70d {+04d 41' 48"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:22:22 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.606d {+11h 14m 25s} (J2000)
POINT_DEC:       -36.741d {-36d 44' 28"} (J2000)
POINT_ROLL:      302.210d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68937.56 SOD {19:08:57.56} UT,   103.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.074
N_STARS:         151
X_OFFSET:        568 [pixels]
Y_OFFSET:        352 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1311 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw01058804000msufc0103.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.43d {+01h 25m 44s}   +4.70d {+04d 41' 52"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [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 02 Jul 21 19:23:34 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.606d {+11h 14m 25s} (J2000)
POINT_DEC:       -36.741d {-36d 44' 28"} (J2000)
ROLL:            302.210d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68937.56 SOD {19:08:57.56} UT,   103.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     646945764
X_OFFSET:        824 [pixels]
Y_OFFSET:        707 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       984
Y_GRB_POS:       867
BINNING_INDEX:   1
IM_URL:          sw01058804000msuni0131.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.44d {+01h 25m 46s}   +4.70d {+04d 42' 08"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:23:54 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.609d {+11h 14m 26s} (J2000)
POINT_DEC:       -36.739d {-36d 44' 21"} (J2000)
POINT_ROLL:      302.209d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  69149.36 SOD {19:12:29.36} UT,   315.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.114
N_STARS:         31
X_OFFSET:        504 [pixels]
Y_OFFSET:        387 [pixels]
X_MAX:           1463 [pixels]
Y_MAX:           1346 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw01058804000msufc0315.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.45d {+01h 25m 47s}   +4.70d {+04d 42' 12"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:23:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.606d {+11h 14m 25s} (J2000)
POINT_DEC:       -36.741d {-36d 44' 28"} (J2000)
ROLL:            302.210d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  68937.56 SOD {19:08:57.56} UT,   103.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     646945764
X_OFFSET:        824 [pixels]
Y_OFFSET:        707 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       984
Y_GRB_POS:       867
BINNING_INDEX:   1
IM_URL:          sw01058804000msuni0131.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 12"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.45d {+01h 25m 47s}   +4.70d {+04d 42' 11"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:24:12 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.609d {+11h 14m 26s} (J2000)
POINT_DEC:       -36.739d {-36d 44' 21"} (J2000)
POINT_ROLL:      302.209d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  69149.36 SOD {19:12:29.36} UT,   315.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.114
N_STARS:         31
X_OFFSET:        504 [pixels]
Y_OFFSET:        387 [pixels]
X_MAX:           1463 [pixels]
Y_MAX:           1346 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw01058804000msufc0315.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 11"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.45d {+01h 25m 48s}   +4.70d {+04d 42' 16"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [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 #30351
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. A. Kennea (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII), S. Laha (GSFC/UMBC/CRESST), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of the Neil Gehrels Swift Observatory Team:
At 19:07:13 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 210702A (trigger=1058804). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 168.570, -36.741 which is
```
   RA(J2000) = 11h 14m 17s
   Dec(J2000) = -36d 44' 28"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 100 sec. The peak count rate was ~10,000 counts/sec (15-350 keV), at ~2 sec after the trigger.
The XRT began observing the field at 19:08:49.2 UT, 95.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 168.5813, -36.7474 which is equivalent to:
```
   RA(J2000)  = 11h 14m 19.51s
   Dec(J2000) = -36d 44' 50.6"
```
with an uncertainty of 11.0 arcseconds (radius, 90% containment). No event data are yet available to determine the column density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 1.00e-08 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 45 seconds with the U filter starting 315 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	11:14:18.83 = 168.57846
  DEC(J2000) = -36:44:48.8  = -36.74690
```
with a 90%-confidence error radius of about 0.61 arc sec. This position is 8.4 arc sec. from the center of the XRT error circle. The estimated magnitude is 11.72 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.121.
Burst Advocate for this burst is A. Y. Lien (amy.y.lien 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/)
GCN Circular #30352
V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, F. Balakin, I. Gorbunov Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University
D. Buckley, S. Potter, A. Kniazev, M. Kotze South African Astronomical Observatory
K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk Irkutsk State University
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk
R. Podesta, Carlos Lopez and F. Podesta Observatorio Astronomico Felix Aguilar (OAFA)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the GRB210702.80 17 sec after notice time and 822 sec after trigger time at 2021-07-02 19:20:56 UT. On our first (160s exposure) set we found 1 optical transient within Swift error-box (ra=168.567 dec=-36.7408 r=0.05) brighter than 18.1.
```
 T-Tmid      Date      Time       Expt.        Ra                Dec           Mag
---------|---------------------|-------|-----------------|-----------------|-------
     902   2021-07-02 19:20:56     160   (11h 14m 18.85s , -36d 44m 49.1s)     12.3
```
The 5-sigma upper limit has been about 18.1mag The message may be cited.
GCN Circular #30353
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University)
MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 210702A ( A. Y. Lien et al., GCN 30351) errorbox 822 sec after trigger time at 2021-07-02 19:20:56 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 51 deg. The sun altitude is -44.7 deg.
The galactic latitude b = 22 deg., longitude l = 283 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1650622
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

     903 |         MASTER-SAAO | P\  |   160 | 18.6 |        
    1084 |         MASTER-SAAO | P\  |   180 | 17.9 |        
    1284 |         MASTER-SAAO | P\  |   180 | 17.6 |        
```
The observation and reduction will continue. The message may be cited.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:25:15 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.609d {+11h 14m 26s} (J2000)
POINT_DEC:       -36.739d {-36d 44' 21"} (J2000)
ROLL:            302.209d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  69149.36 SOD {19:12:29.36} UT,   315.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     646945976
X_OFFSET:        824 [pixels]
Y_OFFSET:        707 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       984
Y_GRB_POS:       867
BINNING_INDEX:   1
IM_URL:          sw01058804000msuni0343.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 11"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.46d {+01h 25m 49s}   +4.71d {+04d 42' 29"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 02 Jul 21 19:25:29 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1058804,   Seg_Num: 0
POINT_RA:        168.609d {+11h 14m 26s} (J2000)
POINT_DEC:       -36.739d {-36d 44' 21"} (J2000)
ROLL:            302.209d
IMG_START_DATE:  19397 TJD;   183 DOY;   21/07/02
IMG_START_TIME:  69149.36 SOD {19:12:29.36} UT,   315.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     646945976
X_OFFSET:        824 [pixels]
Y_OFFSET:        707 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       984
Y_GRB_POS:       867
BINNING_INDEX:   1
IM_URL:          sw01058804000msuni0343.fits
SUN_POSTN:       102.10d {+06h 48m 23s}  +22.97d {+22d 58' 11"}
SUN_DIST:         86.76 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:       21.46d {+01h 25m 50s}   +4.71d {+04d 42' 32"}
MOON_DIST:       136.15 [deg]
MOON_ILLUM:      41 [%]
GAL_COORDS:      282.11, 22.18 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      186.73,-37.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #30354
P.J. Groot (Radboud/UCT/SAAO), S. de Wet (UCT), P.M. Vreeswijk (Radboud), A.J. Levan (Radboud) report on behalf of the MeerLICHT consortium:
Following the detection of GRB210702A by Swift and its optical counterpart (Lien et al., GCN30351), the 0.6m MeerLICHT telescope, located at Sutherland, South Africa obtained a series of 60s images in the q,u,q,g,q,r,q,i,q,z,q,u,q,g,q bands, starting at 2021-07-02, 19:23:26.586 UT, 16 minutes after the Swift detection, and 3 minutes after the distribution of the BAT alert.
The source identified by Swift UVOT is clearly detected as a new transient at coordinates
```
RA(ICRS) = 168.57839 =  11:14:18.81 (+/-0.06”)
DEC(ICRS)= -36.74702 = -36:44:49.27 (+/- 0.04”)
```
MeerLICHT astrometry is calibrated against Gaia DR2.
The first source detections are, at:
```
q = 12.815 +/- 0.001 +/- 0.018   (19:23:26 UT)
u = 13.585 +/- 0.004 +/- 0.041   (19:25:10 UT)
g = 13.394 +/- 0.002 +/- 0.021   (19:28:46 UT)
r = 13.193 +/- 0.002 +/- 0.015	(19:32:18 UT)
i = 13.096 +/- 0.003 +/- 0.034   (19:35:42 UT)	  
z = 13.100 +/- 0.004 +/- 0.025   (19:39:25 UT)
```
where the first uncertainty on the magnitude is the statistical uncertainty and the second is the uncertainty on the photometric calibration.
Our repeated q-band observations show decay consistent with a power law with exponent of approximately -1.2.
Further data taking was suspended due to high winds.
Reference images of the field show no underlying host galaxy down to the 5-sigma limiting magnitude, at the position of the afterglow, at:
```
u > 19.54
g > 20.44
q > 21.23
r > 20.20
i > 19.72
z > 18.90
```
MeerLICHT is built and run by a consortium consisting of Radboud University, University of Cape Town, the South African Astronomical Observatory, the University of Oxford, the University of Manchester and the University of Amsterdam.
GCN Circular #30355
N. P. M. Kuin (UCL-MSSL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT obtained a 49s grism spectrum of GRB 210702A starting 282 s after the BAT trigger (Lien et al., GCN Circ. 30351). The spectrum shows a clear break at 2011 Angstrom, and absorption features attributable to Ly-alpha and Ly-beta suggesting a redshift of z=1.1757+/-0.0093. An possible intervening system is present at z=1.050 based on a weaker line seen at 2492A.
The wavelength anchor/zeropoint in the uv grism is uncertain by typically 15A, which translates to an uncertainty as quoted in the redshift above.
GCN Circular #30356
N. P. M. Kuin (UCL-MSSL) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210702A 104 s after the BAT trigger (Lien et al., GCN Circ. 30351). A source consistent with the XRT position (Lien et al. GCN Circ. 30351) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
    RA  (J2000) =  11:14:18.70 = 168.57793 (deg.)
    Dec (J2000) = -36:44:50.0  = -36.74723 (deg.)
```
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
Preliminary detections 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

white              104          254          147         15.70 +/- 0.02
b                 3516         3716          197         15.46 +/- 0.03
u                  316          361           44         11.37 +/- 0.05
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.121 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #30357
D. Xu (NAOC), L. Izzo (DARK/NBI), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. A. Kann (HETH/IAA-CSIC), S. Y. Fu (NAOC), S. Campana (INAF-OAB), V. D'Elia (ASI/SSDC, INAF/OAR), A. J. Levan (Radboud U. Nijmegen), B. Milvang-Jensen (DAWN/NBI), D. A. Perley (LJMU), G. Pugliese (API, Univ. Amsterdam), R. L. C. Starling (Univ. Leicester), N. R. Tanvir (Univ. Leicester), S. Vergani (CNRS - Observatoire de Paris/GEPI), and K. Wiersema (Univ. Warwick) report on behalf of the Stargate Consortium:
We observed the bright afterglow (Lien et al., GCN #30351; Lipunov et al., GCN #30352; Groot et al., GCN #30354; Kuin et al., GCN #30356) of GRB 210702A (Lien et al., GCN #30351) using the ESO VLT UT3 (Melipal) equipped with the X-shooter spectrograph. Our spectra cover the wavelength range 3000-25000 AA, and consist of 4 exposures of 600 s each. The observation mid-time was 2021 July 2.997 UT (i.e., 4.80 hr after the GRB).
In a 20 s image taken with the acquisition camera on July 02.975 UT, we detect the optical afterglow at r' = 16.91 +/- 0.01 mag (AB system), measured against three SkyMapper field stars.
In our spectrum, strong continuum is detected over the whole observed range. We detect a plethora of metallic absorption features, among them Si II, Si II*, C IV, Fe II, Fe II*, Al II, Ni II, Ni II*, Al III, Zn II, Mg I, Cr II, Mn II, Mg II, Mg I, and Ca II, all at a common redshift of z = 1.160. This is about 1.5 sigma lower than, but is broadly consistent with the value reported by Swift/UVOT (Kuin et al., GCN #30355). No emission feature is present in the spectrum. The detection of excited transitions establishes this as the redshift of the GRB.
There is also an intervening system detected at z = 0.538 showing Mg II and Mg I absorption features.
We acknowledge excellent support from the observing staff at Paranal, in particular Alain Smette and Bin Yang.
GCN Circular #30358
V. D'Elia (SSDC & INAF-OAR), A. D'Ai (INAF-IASFPA), J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB) and A.Y. Lien report on behalf of the Swift-XRT team:
We have analysed 6.3 ks of XRT data for GRB 210702A (Lien et al. GCN Circ. 30351), from 84 s to 38.4 ks after the BAT trigger. The data comprise 310 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. Using 4559 s of PC mode data and 10 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 = 168.57877, -36.74715 which is equivalent to:
```
RA (J2000): 11h 14m 18.91s
Dec(J2000): -36d 44' 49.7"
```
with an uncertainty of 1.9 arcsec (radius, 90% confidence).
The light curve can be modelled with an initial power-law decay with an index of alpha=1.005 (+0.014, -0.013), followed by a break at T+7161 s to an alpha of 1.68 (+0.11, -0.10).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.570 (+0.018, -0.015). The best-fitting absorption column is consistent with the Galactic value of 1.2 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.95 (+/-0.07) and a best-fitting absorption column of 1.8 (+/-1.0) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Galactic foreground: 1.2 x 10^21 cm^-2
Intrinsic column:    1.8 (+/-1.0) x 10^21 cm^-2 at z=1.16
Photon index:	     1.95 (+/-0.07)
```
If the light curve continues to decay with a power-law decay index of 1.68, the count rate at T+24 hours will be 0.044 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.6 x 10^-12 (2.0 x 10^-12) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01058804.
This circular is an official product of the Swift-XRT team.
GCN Circular #30362
K. Yamaoka (Nagoya U), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), S. Nakahira (RIKEN), Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration:
The long bright GRB 210702A (Swift detection: Lien et al., GCN Circ. 30351; https://gcn.gsfc.nasa.gov/other/210702A.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 19:07:06.474 UTC on 2 July 2021 (http://cgbm.calet.jp/cgbm_trigger/flight/1309287819/index.html). The burst signal was seen by all CGBM detectors.
The burst light curve shows a FRED-like pulse which starts at T+2.1 sec, peaks at T+6.3 sec,and ends at T+51.3 sec. The T90 and T50 durations measured by the SGM data are 32.1 +- 4.6 sec and 9.2 +- 0.9 sec (40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1309287819/
The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN Circular #30363
A. Ursi (INAF/IAPS), C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C. Casentini, Y. Evangelista, G. Piano (INAF/IAPS), F. Lucarelli (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M. Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois (INAF/OA-Cagliari), F. Longo (Univ. Trieste and INFN Trieste), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi), report on behalf of the AGILE Team:
The AGILE satellite detected the long GRB 210702A at T0 = 2021-07-02 19:07:13 s (UTC), reported by Swift (GCNs #30351, #30352, #30356, #30358) and CALET (#30362).
The burst is clearly visible in the AGILE scientific ratemeters of the SuperAGILE (SA; 20-60 keV), MiniCALorimeter (MCAL; 0.4-100 MeV), and AntiCoincidence (AC; 50-200 keV) detectors. The event lasted about ~32 s and it released a total number of 1630 counts in the SA detector (above a background rate of 50 Hz), 40500 counts in the MCAL detector (above a background rate of 1440 Hz), and 74310 counts in the AC detector (above a background rate of 3610 Hz). The AGILE ratemeter light curves can be found at http://www.agilescienceapp.it/notices/GRB210702A_AGILE_RM.png . The event also triggered a partial high time resolution MCAL data acquisition.
Additional analysis of AGILE data is in progress.
GCN Circular #30364
```
TITLE:   GCN CIRCULAR
NUMBER:  30364
SUBJECT: GRB 210702A: iTelescope optical afterglow observations
DATE:    21/07/03 11:42:59 GMT
FROM:    Filipp Dmitrievich Romanov at Amateur astronomer  
```
I observed the field of GRB 210702A (Lien et al., GCN Circ. 30351) using remote telescope T17 (0.43-m f/6.8 reflector + CCD) of iTelescope.Net in Siding Spring Observatory (Australia) on 2021-07-03. Two images were obtained from 09:00:31 UTC and from 09:01:57 UTC with Sloan I filter (60 seconds exposures, BINx1) and one image was obtained from 09:04:38 UTC with Sloan R filter (300 seconds exposure, BINx1).
I detected optical afterglow with UVOT position in stacked image with SI filter (mid time = 09:01:44 UTC, that is 13h 54m 31s after the trigger) and in the image with SR filter (mid time = 09:07:08 UTC, that is 13h 59m 55s after the trigger) and measured the following magnitudes from comparison to magnitudes of nearby stars from APASS DR9 catalogue (Henden et al., 2016): 18.6 i' +/- 0.4 and 19.0 r' +/- 0.5.
Magnitudes were not corrected for Galactic extinction.
Images available here: https://www.flickr.com/photos/filipp-romanov/51286698321
GCN Circular #30365
S. Belkin (IKI), A. Pozanenko (IKI), N. Pankov (HSE, IKI), M. Krugov (FAI) report on behalf of GRB IKI FuN collaboration:
We observed the field of Swift GRB 210702A (Lien et al., GCN 30351) with Chilescope RC-1000 starting on 2021-07-02 (UT) 23:40:26 in r'-filter. Within enhanced XRT position (D'Elia et al., GCN 30358) we clearly detect the afterglow (Lien et al., GCN 30351; Lipunov et al., GCN 30352; Groot et al., GCN 30354; Kuin et al., GCN 30355; Kuin et al., GCN 30356; Xu et al., GCN 30357; Romanov et al., GCN 30364).
Preliminary photometry of the afterglow is following
```
Date UT start       t-T0 Filter Exp.  OT(AB) Err. UL(AB)
                     (mid, days) (s)

2021-07-02 23:40:26 0.193202 r' 1*600 17.01  0.05  19.7
```
The photometry is based on nearby stars from the APASS_DR8
```
RA DEC r
11:14:16.46880 -36:49:58.2132 15.187
11:14:36.96576 -36:48:30.0132 15.320
```
GCN Circular #30366
D. Frederiks, S. Golenetskii, A.Lysenko, A. Ridnaia, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report:
The long GRB 210702A (Swift detection: Lien et al., GCN 30351; CALET GRBM detection: Yamaoka et al., GCN 30362; AGILE detection: Ursi et al., GCN 30363) triggered Konus-Wind (KW) at T0=68826.870 s UT (19:07:06.870).
The burst light curve shows a bright, FRED-like pulse which starts at ~T0-4 s, and has a total duration of ~90 s. The emission is seen up to ~15 MeV.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB210702_T68826/
As observed by Konus-Wind, the burst had a fluence of (2.5 � 0.2)x10^-4 erg/cm^2 and a 64-ms peak energy flux, measured from T0 + 7.808 s, of (3.0 � 0.2)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum (measured from T0 to T0+86.784 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.91 (-0.09,+0.10), the high energy photon index beta = -1.91 (-0.10,+0.08), the peak energy Ep = 376 (-61,+63) keV, chi2 = 107/97 dof.
The spectrum near the peak count rate (measured from T0+4.096 to T0+7.936 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.78 (-0.09,+0.11), the high energy photon index beta = -2.00 (-0.09,+0.08), the peak energy Ep = 402 (-64,+66) keV, chi2 = 111/92 dof.
Assuming the redshift z=1.160 (Xu et al., GCN 30357) and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014), we estimate the isotropic energy release E_iso to ~9.3x10^53 erg, the isotropic luminosity L_iso to ~2.4x10^53 erg/s, the rest-frame peak energy of the time-integrated spectrum Epi,z to ~812 keV, and the rest-frame peak energy of the 'peak' spectrum Epp,z to ~870 keV. With these values, GRB 210702A is within 68% prediction bands for both 'Amati' and 'Yonetoku' relations for the sample of >300 long KW GRBs with known redshifts (Tsvetkova et al., 2021, ApJ, 908, 83), see http://www.ioffe.ru/LEA/GRBs/GRB210702_T68826/GRB210702A_rest_frame.pdf
All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary.
GCN Circular #30367
Y.-D. Hu, E. Fernandez-Garcia, T.-R. Sun, A. J. Castro-Tirado, M. D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), I. Carrasco and C. Perez del Pulgar (Univ. de Malaga), and R. Querel (NIWA), on behalf of a larger collaboration, report:
The 60cm BOOTES-3/YA robotic telescope at NIWA Lauder in Otago (New Zealand) automatically responded to the Swift trigger of GRB 210702A (Lien et al. GCNC 30351), which also detected by CALET (Yamaoka et al. GCNC 30362) and AGILE (Ursi et al. GCNC 30363), after the twilight as soon as possible. The first image (clear filter) were obtained starting at 07:00:58 UT (~11.9 hrs after trigger). At the enhanced Swift/XRT position(D'Elia et al. GCNC 30358), we found the optical counterpart reported by MASTER (Lipunov et al. GCNC 30352), MeerLICHT (Groot et al. GCNC 30354), Swift/UVOT (Lien et al. GCNC 30351, Kuin et al. GCNC 30355), VLT (Xu et al. GCNC 30357), iTelescope (Romanov GCNC 30364) and Chilescope (Belkin et al. GCNC 30365) with a magnitude of R = 18.0+-0.1 in the co-added image (10 x 60 s), which calibrated with nearby stars in USNO-B 1.0 catalog. Further analysis is ongoing.
We thank the staff at NIWA for its excellent support.
GCN Circular #30368
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 210702A (trigger #1058804) (Lien et al., GCN Circ. 30351). The BAT ground-calculated position is RA, Dec = 168.570, -36.741 deg which is
```
   RA(J2000)  =  11h 14m 16.8s
   Dec(J2000) = -36d -44' -29.2"
```
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 4%.
The mask-weighted light curve shows a single-peaked FRED-like structure that starts at ~T-4 s, peaks at ~T+1 s, and ends at ~T+370 s. The burst went out of the BAT field of view at T+452 s. There might be addition burst emission afterwards. T90 (15-350 keV) is 138.2 +- 47.6 sec (estimated error including systematics).
The burst occurred at a location with a very low partial coding fraction, and thus was out of the BAT calibrated field of view until ~T+18 s. Therefore, the spectral analysis is only available for the burst duration afterwards. The time-averaged spectrum from T+18.0 to T+369.2 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.54 +- 0.09. The fluence in the 15-150 keV band is 9.8 +- 0.5 x 10^-6 erg/cm2. 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/1058804/BA/
GCN Circular #30423
T. Laskar (University of Bath) and D. Perley (LJMU) report on behalf of a larger collaboration:
"We observed GRB 210702A (Lien et al. GCN 30351) with the Atacama Large Millimeter/Submillimeter Array (ALMA) at 97.5 GHz and 343.5 GHz beginning on 2021 July 03 21:05:52 UT (26.0 h after the burst). ALMA observations of this burst were delayed due to uninterruptible scheduled Cycle 8 software validation at the Observatory.
Preliminary analysis reveals a mm source with flux density of ~ 0.1 mJy at 97.5 GHz and position:
```
RA (J2000) = 11:14:18.807
Dec (J2000) = -36:44:49.25
```
with uncertainty ~ 0.03" in each coordinate, consistent with the X-ray position (D'Elia et al., GCN 30358) and optical position (Lien et al., GCN 30351; Kuin et al., GCN 30356). The spectrum appears strongly self-absorbed in the mm-band. Further observations are planned.
We thank the JAO staff, AoD, P2G, and the entire ALMA team for their help with these observations."
GCN Circular #30424
T. Laskar (University of Bath), S. Bhandari (CSIRO), K. D. Alexander (Northwestern), E. Berger (Harvard), R. Chornock (UC Berkeley), D. Coppejans (Northwestern), M. Drout (U. Toronto), H. van Eerten (University of Bath), Wen-fai Fong (Northwestern), C. Guidorzi (U. Ferrara), R. Margutti (UC Berkeley), C. G. Mundell (University of Bath), P. Schady (University of Bath), and G. Schroeder (Northwestern) report:
"We observed GRB 210702A (Lien et al., GCN 30351) with the Australia Telescope Compact Array (ATCA) at multiple frequencies beginning on 2021 July 06 05:00 UT. We detect a radio counterpart at 16.7, 21.2, and 34 GHz at a position consistent with the X-ray position (D'Elia et al., GCN 30358), optical position (Lien et al., GCN 30351; Kuin et al., GCN 30356), and mm-band position (Laskar et al., GCN 30423) with a flux density of ~ 0.8 mJy at 34 GHz at a mid-time of 3.50 days after the burst.
Further observations are planned.
We thank the CSIRO staff for approving and scheduling these observations."
GCN Circular #30477
T. Laskar (U. of Bath) and S. Bhandari (CSIRO) report on behalf of a larger collaboration:
"Following the initial detection of the radio counterpart of GRB 210702A (Lien et al., GCN 30351) with the Australia Telescope Compact Array (ATCA) on 2021 July 06, 3.50 days after the burst (Laskar et al., GCN 30424), we have been monitoring this source with ATCA at 5.5, 9.0, 16.7, 21.2, and 34 GHz. The 34 GHz radio counterpart was observed to fade, until observations taken on 2021 July 13 indicated a non-detection with map rms ~ 60 uJy at a mid-time of 10.3 days after the burst.
We observed GRB 210702A with ATCA again at the above frequencies beginning on 2021 July 21 07:00 UTC with the array in a hybrid (H168) configuration. Preliminary analysis reveals a strong (> 10 sigma) detection at 34 GHz with a flux density of ~ 0.7 mJy at a mid-time of 18.5 days after the burst, implying a significant rebrightening of the radio afterglow. Similar rebrightening is observed at 21.2 and 16.7 GHz.
Detailed analysis is ongoing and further observations are planned. We thank the CSIRO staff for approving and scheduling these observations.
The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the Observatory site."
GCN Circular #30479
T. Laskar (U. of Bath) reports on behalf of a larger collaboration:
"Following the initial detection of the mm counterpart of GRB 210702A (Lien et al., GCN 30351) with the Atacama Large Millimeter/Submillimeter Array (ALMA) on 2021 July 03, 26 h after the burst (Laskar & Perley, GCN 30423), we have been monitoring this source with ALMA at 97.5 GHz. The mm-band counterpart was observed to fade to a flux density of ~ 0.3 mJy in observations taken on 2021 July 11 at a mid-time of 8.3 days after the burst.
We observed GRB 210702A with ALMA again beginning on 2021 July 20 21:02 UTC. Preliminary analysis reveals a strong (~ 50 sigma) detection at 97.5 GHz with a flux density of ~ 0.8 mJy at a mid-time of 18.1 days after the burst, implying a significant rebrightening of the mm-band afterglow, contemporaneous to the radio rebrightening observed at 34, 21.2, and 16.7 GHz with ATCA (Laskar & Bhandari, GCN 30477). Further observations are planned.
We thank the JAO staff, AoD, P2G, and the entire ALMA team for their help with these observations."
GCN Circular #30538
T. Laskar (University of Bath), S. Buchner (SARAO), S. Legodi (SARAO), K. D. Alexander (Northwestern), E. Ayache (Bath), E. Berger (Harvard), S. Bhandari (CSIRO), J. Bright (Northwestern), R. Chornock (UC Berkeley), D. Coppejans (Northwestern), H. van Eerten (Bath), W. Fong (Northwestern), R. Margutti (UC Berkeley), C.G. Mundell (Bath), P. Schady (Bath), and G. Schroeder (Northwestern) report:
"We observed GRB 210702A (Lien et al. GCN 30351) with the MeerKAT radio telescope array over two epochs beginning on 2021 July 11 12:16 UTC (8.7 d after the burst) and 2021 July 23 18:16 UTC (21.0 d after the burst), respectively. Preliminary analysis reveals a brightening radio counterpart with 1.284 GHz flux density of 123 +/- 12 uJy at 21.0 d at position:
```
RA (J2000) = 11:14:18.76
Dec (J2000) = -36:44:49.5
```
with uncertainty ~ 0.4" in each coordinate, consistent with the X-ray position (D'Elia et al., GCN 30358), optical position (Lien et al., GCN 30351; Kuin et al., GCN 30356), and mm-band position (Laskar & Perley, GCN 30423). Further observations are planned.
The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation."

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Jochen Greiner, last update: 28-Jul-2021 [Disclaimer]