Gamma-ray Burst 220715B

(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 15 Jul 22 22:25:01 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1116441,   Seg_Num: 0
GRB_RA:          254.889d {+16h 59m 33s} (J2000),
                 255.258d {+17h 01m 02s} (current),
                 254.070d {+16h 56m 17s} (1950)
GRB_DEC:         -33.597d {-33d 35' 48"} (J2000),
                 -33.629d {-33d 37' 45"} (current),
                 -33.523d {-33d 31' 20"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3878 [cnts]    Image_Peak=277 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       19877 [cnts]
BKG_TIME:        80666.49 SOD {22:24:26.49} UT
BKG_DUR:         8 [sec]
GRB_DATE:        19775 TJD;   196 DOY;   22/07/15
GRB_TIME:        80682.17 SOD {22:24:42.17} UT
GRB_PHI:          43.42 [deg]
GRB_THETA:        12.47 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     24.85 [sigma]
IMAGE_SIGNIF:    11.46 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +1  +0  +1 +79  +0 
SUN_POSTN:       115.26d {+07h 41m 03s}  +21.41d {+21d 24' 22"}
SUN_DIST:        142.74 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      327.95d {+21h 51m 47s}  -18.29d {-18d 17' 40"}
MOON_DIST:        65.85 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.58,  5.47 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      257.23,-10.83 [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 = 349.96,10.72 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=679616687).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:25:31 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      57
TRIGGER_NUM:     679616687
GRB_RA:          270.180d {+18h 00m 43s} (J2000),
                 270.567d {+18h 02m 16s} (current),
                 269.322d {+17h 57m 17s} (1950)
GRB_DEC:         -38.030d {-38d 01' 47"} (J2000),
                 -38.029d {-38d 01' 44"} (current),
                 -38.029d {-38d 01' 43"} (1950)
GRB_ERROR:       10.42 [deg radius, statistical only]
DATA_SIGNIF:     8.70 [sigma]
DATA_INTERVAL:   2.048 [sec]
GRB_DATE:        19775 TJD;   196 DOY;   22/07/15
GRB_TIME:        80682.74 SOD {22:24:42.74} UT
GRB_PHI:         154.00 [deg]
GRB_THETA:        70.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4173 (Gnd S/W Version number)
SUN_POSTN:       115.26d {+07h 41m 03s}  +21.41d {+21d 24' 22"}
SUN_DIST:        153.02 [deg]   Sun_angle= -10.4 [hr] (East of Sun)
MOON_POSTN:      327.95d {+21h 51m 49s}  -18.29d {-18d 17' 34"}
MOON_DIST:        53.38 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      353.71, -7.30 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      270.15,-14.59 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_lc_medres34_bn220715934.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_679616687.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=1116441).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:25:12 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     679616687
GRB_RA:          253.400d {+16h 53m 36s} (J2000),
                 253.740d {+16h 54m 58s} (current),
                 252.646d {+16h 50m 35s} (1950)
GRB_DEC:         -23.150d {-23d 08' 59"} (J2000),
                 -23.185d {-23d 11' 07"} (current),
                 -23.069d {-23d 04' 06"} (1950)
GRB_ERROR:       19.78 [deg radius, statistical plus systematic]
GRB_INTEN:       129 [cnts/sec]
DATA_SIGNIF:     7.20 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        19775 TJD;   196 DOY;   22/07/15
GRB_TIME:        80682.74 SOD {22:24:42.74} UT
GRB_PHI:         134.00 [deg]
GRB_THETA:        60.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.61
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      94%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       1,0,0, 0,0,0, 0,0,0, 1,1,1, 0,0,
SUN_POSTN:       115.26d {+07h 41m 03s}  +21.41d {+21d 24' 22"}
SUN_DIST:        141.67 [deg]   Sun_angle= -9.2 [hr] (East of Sun)
MOON_POSTN:      327.95d {+21h 51m 48s}  -18.29d {-18d 17' 38"}
MOON_DIST:        68.83 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      358.15, 12.90 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      254.77, -0.58 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_lc_medres34_bn220715934.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 27.55,-15.45 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=1116441).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:34:08 UT
NOTICE_TYPE:     Fermi-GBM Final Position
RECORD_NUM:      0
TRIGGER_NUM:     679616687
GRB_RA:          221.710d {+14h 46m 50s} (J2000),
                 222.061d {+14h 48m 15s} (current),
                 220.934d {+14h 43m 44s} (1950)
GRB_DEC:         -36.440d {-36d 26' 23"} (J2000),
                 -36.533d {-36d 32' 00"} (current),
                 -36.231d {-36d 13' 50"} (1950)
GRB_ERROR:       16.52 [deg radius, statistical only]
GRB_DATE:        19775 TJD;   196 DOY;   22/07/15
GRB_TIME:        80682.74 SOD {22:24:42.74} UT
GRB_PHI:         119.00 [deg]
GRB_THETA:        87.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41731 (Gnd S/W Version number)
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 19"}
SUN_DIST:        115.68 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      328.04d {+21h 52m 10s}  -18.26d {-18d 15' 45"}
MOON_DIST:        91.35 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      327.48, 20.87 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      230.45,-19.39 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_lc_medres34_bn220715934.gif
LOC_URL:         http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_locplot_all_bn220715934.png
COMMENTS:        Fermi-GBM Final Position.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file should be available by the time this FINAL notice is produced.  
COMMENTS:        This notice was generated completely by automated pipeline processing.  
COMMENTS:        This is likely a Long GRB.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=1116441).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:26:42 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.899d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.589d {-33d 35' 19"} (J2000)
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80780.97 SOD {22:26:20.97} UT,   98.8 [sec] since BAT Trigger Time
COUNTS:          49    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        4    Max_iter_allowed= 4
ERROR_CODE:      2
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        Algorithm did not converge; too many iterations.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:29:02 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1116441,   Seg_Num: 0
GRB_RA:          254.889d {+16h 59m 33s} (J2000),
                 255.258d {+17h 01m 02s} (current),
                 254.070d {+16h 56m 17s} (1950)
GRB_DEC:         -33.597d {-33d 35' 48"} (J2000),
                 -33.629d {-33d 37' 45"} (current),
                 -33.523d {-33d 31' 20"} (1950)
GRB_DATE:        19775 TJD;   196 DOY;   22/07/15
GRB_TIME:        80682.17 SOD {22:24:42.17} UT
TRIGGER_INDEX:   146
GRB_PHI:          43.42 [deg]
GRB_THETA:        12.47 [deg]
DELTA_TIME:      32.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     24.85 [sigma]
IMAGE_SIGNIF:    11.46 [sigma]
LC_URL:          sw01116441000msb.lc
SUN_POSTN:       115.26d {+07h 41m 04s}  +21.41d {+21d 24' 21"}
SUN_DIST:        142.74 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      327.99d {+21h 51m 57s}  -18.28d {-18d 16' 50"}
MOON_DIST:        65.89 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.58,  5.47 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      257.23,-10.83 [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 = 349.96,10.72 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:31:07 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.898d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.588d {-33d 35' 17"} (J2000)
POINT_ROLL:      261.757d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80784.97 SOD {22:26:24.97} UT,   102.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.052
N_STARS:         190
X_OFFSET:        516 [pixels]
Y_OFFSET:        489 [pixels]
X_MAX:           1475 [pixels]
Y_MAX:           1448 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw01116441000msufc0102.fits
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 20"}
SUN_DIST:        142.75 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.01d {+21h 52m 02s}  -18.27d {-18d 16' 23"}
MOON_DIST:        65.91 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.23,-10.82 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:30:26 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     1116441,   Seg_Num: 0
GRB_RA:          254.8755d {+16h 59m 30.11s} (J2000),
                 255.2448d {+17h 00m 58.76s} (current),
                 254.0570d {+16h 56m 13.68s} (1950)
GRB_DEC:         -33.5977d {-33d 35' 51.7"} (J2000),
                 -33.6300d {-33d 37' 48.1"} (current),
                 -33.5231d {-33d 31' 23.3"} (1950)
GRB_ERROR:       5.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80788.00 SOD {22:26:28.00} UT,   105.8 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 20"}
SUN_DIST:        142.73 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.00d {+21h 52m 01s}  -18.28d {-18d 16' 32"}
MOON_DIST:        65.92 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.57,  5.48 [deg] galactic lon,lat of the burst
ECL_COORDS:      257.22,-10.83 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:31:23 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.898d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.588d {-33d 35' 17"} (J2000)
POINT_ROLL:      261.757d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80784.97 SOD {22:26:24.97} UT,   102.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.052
N_STARS:         190
X_OFFSET:        516 [pixels]
Y_OFFSET:        489 [pixels]
X_MAX:           1475 [pixels]
Y_MAX:           1448 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw01116441000msufc0102.fits
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 20"}
SUN_DIST:        142.75 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.01d {+21h 52m 03s}  -18.27d {-18d 16' 20"}
MOON_DIST:        65.91 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.23,-10.82 [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 15 Jul 22 22:32:42 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.898d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.588d {-33d 35' 17"} (J2000)
ROLL:            261.757d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80784.97 SOD {22:26:24.97} UT,   102.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     679616814
X_OFFSET:        835 [pixels]
Y_OFFSET:        808 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       995
Y_GRB_POS:       968
BINNING_INDEX:   1
IM_URL:          sw01116441000msuni0132.fits
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 19"}
SUN_DIST:        142.75 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.03d {+21h 52m 06s}  -18.27d {-18d 16' 03"}
MOON_DIST:        65.92 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.23,-10.82 [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).  
COMMENTS:        This notice was forced out after watchdog timer expiring -- most likely due to missing packet(s);  
COMMENTS:        as a consequence some of the fields may be incoorect (eg TRIGGER_NUM,RA,DEC).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:32:52 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.898d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.588d {-33d 35' 17"} (J2000)
ROLL:            261.757d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80784.97 SOD {22:26:24.97} UT,   102.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     679616814
X_OFFSET:        835 [pixels]
Y_OFFSET:        808 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       995
Y_GRB_POS:       968
BINNING_INDEX:   1
IM_URL:          sw01116441000msuni0132.fits
SUN_POSTN:       115.27d {+07h 41m 04s}  +21.41d {+21d 24' 19"}
SUN_DIST:        142.75 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.03d {+21h 52m 06s}  -18.27d {-18d 16' 01"}
MOON_DIST:        65.93 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.23,-10.82 [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.  
COMMENTS:        This notice was forced out after watchdog timer expiring -- most likely due to missing packet(s);  
COMMENTS:        as a consequence some of the fields may be incoorect (eg TRIGGER_NUM,RA,DEC).

GCN Circular #32404
The Fermi GBM team reports the detection of a likely LONG GRB
At 22:24:42 UT on 15 Jul 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220715B (trigger 679616687.73956 / 220715934).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 221.7, Dec = -36.4 (J2000 degrees, equivalent to J2000 14h 46m, -36d 23'), with a statistical uncertainty of 16.5 degrees.
The angle from the Fermi LAT boresight is 87.0 degrees.
The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_skymap_all_bn220715934.png
The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_healpix_all_bn220715934.fit
The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220715934/quicklook/glg_lc_medres34_bn220715934.gif
GCN Circular #32405
E. Troja (NASA/GSFC/UMCP), P. D'Avanzo (INAF-OAB), S. Dichiara (PSU), M. Ferro (INAF-OAB), J.D. Gropp (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII), T. Sbarrato (INAF-OAB) and M. A. Williams (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 22:24:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220715B (trigger=1116441). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 254.889, -33.597 which is
```
   RA(J2000) = 16h 59m 33s
   Dec(J2000) = -33d 35' 48"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 50 sec. The peak count rate was ~2400 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 22:26:20.9 UT, 98.8 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 254.87520, -33.59766 which is equivalent to:
```
   RA(J2000)  = 16h 59m 30.05s
   Dec(J2000) = -33d 35' 51.6"
```
with an uncertainty of 5.7 arcseconds (radius, 90% containment). This location is 41 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 https://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 3.58 x 10^21 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 102 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 none of the XRT error circle. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the region. No correction has been made for the expected extinction corresponding to E(B-V) of 0.525.
Burst Advocate for this burst is E. Troja (nora.gsfc 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/)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:54:13 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.899d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.590d {-33d 35' 23"} (J2000)
POINT_ROLL:      261.756d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80997.79 SOD {22:29:57.79} UT,   315.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.413
N_STARS:         190
X_OFFSET:        276 [pixels]
Y_OFFSET:        249 [pixels]
X_MAX:           1715 [pixels]
Y_MAX:           1688 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01116441000msufc0315.fits
SUN_POSTN:       115.28d {+07h 41m 08s}  +21.40d {+21d 24' 10"}
SUN_DIST:        142.73 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.24d {+21h 52m 58s}  -18.19d {-18d 11' 32"}
MOON_DIST:        66.14 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.24,-10.82 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:54:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:        254.899d {+16h 59m 36s} (J2000)
POINT_DEC:       -33.590d {-33d 35' 23"} (J2000)
POINT_ROLL:      261.756d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80997.79 SOD {22:29:57.79} UT,   315.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.413
N_STARS:         190
X_OFFSET:        276 [pixels]
Y_OFFSET:        249 [pixels]
X_MAX:           1715 [pixels]
Y_MAX:           1688 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01116441000msufc0315.fits
SUN_POSTN:       115.28d {+07h 41m 08s}  +21.40d {+21d 24' 10"}
SUN_DIST:        142.73 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.25d {+21h 52m 59s}  -18.19d {-18d 11' 28"}
MOON_DIST:        66.14 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.59,  5.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      257.24,-10.82 [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 15 Jul 22 22:55:15 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     1116441,   Seg_Num: 0
GRB_RA:          254.8744d {+16h 59m 29.85s} (J2000),
                 255.2437d {+17h 00m 58.49s} (current),
                 254.0559d {+16h 56m 13.42s} (1950)
GRB_DEC:         -33.5979d {-33d 35' 52.4"} (J2000),
                 -33.6302d {-33d 37' 48.8"} (current),
                 -33.5233d {-33d 31' 24.0"} (1950)
GRB_ERROR:       1.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  80788.00 SOD {22:26:28.00} UT,   105.8 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       115.28d {+07h 41m 08s}  +21.40d {+21d 24' 10"}
SUN_DIST:        142.71 [deg]   Sun_angle= -9.3 [hr] (East of Sun)
MOON_POSTN:      328.25d {+21h 53m 01s}  -18.19d {-18d 11' 19"}
MOON_DIST:        66.17 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:      350.57,  5.48 [deg] galactic lon,lat of the burst
ECL_COORDS:      257.22,-10.83 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:56:26 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:          0.000d {+00h 00m 00s} (J2000)
POINT_DEC:        +0.000d {+00d 00' 00"} (J2000)
ROLL:            -33.590d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  82124.88 SOD {22:48:44.88} UT,   1442.7 [sec] since BAT Trigger Time
FILTER:          0, illegal value
EXPOSURE_ID:     65537
X_OFFSET:        911 [pixels]
Y_OFFSET:        1278 [pixels]
WIDTH:           800 [pixels]
HEIGHT:          1821 [pixels]
X_GRB_POS:       0
Y_GRB_POS:       0
BINNING_INDEX:   0
IM_URL:          sw01116441000msuni0345.fits
SUN_POSTN:       115.28d {+07h 41m 08s}  +21.40d {+21d 24' 10"}
SUN_DIST:        113.12 [deg]   Sun_angle= 7.7 [hr] (West of Sun)
MOON_POSTN:      328.27d {+21h 53m 04s}  -18.18d {-18d 11' 04"}
MOON_DIST:        36.41 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:       96.34,-60.19 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        0.00,  0.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        WARNING: This Notice was received with 1 (or more) critical values out of range.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 1x1 binning (ie no compression).  
COMMENTS:        This notice was forced out after watchdog timer expiring -- most likely due to missing packet(s);  
COMMENTS:        as a consequence some of the fields may be incoorect (eg TRIGGER_NUM,RA,DEC).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 15 Jul 22 22:56:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1116441,   Seg_Num: 0
POINT_RA:          0.000d {+00h 00m 00s} (J2000)
POINT_DEC:        +0.000d {+00d 00' 00"} (J2000)
ROLL:            -33.590d
IMG_START_DATE:  19775 TJD;   196 DOY;   22/07/15
IMG_START_TIME:  82124.88 SOD {22:48:44.88} UT,   1442.7 [sec] since BAT Trigger Time
FILTER:          0, illegal value
EXPOSURE_ID:     65537
X_OFFSET:        911 [pixels]
Y_OFFSET:        1278 [pixels]
WIDTH:           800 [pixels]
HEIGHT:          1821 [pixels]
X_GRB_POS:       0
Y_GRB_POS:       0
BINNING_INDEX:   0
IM_URL:          sw01116441000msuni0345.fits
SUN_POSTN:       115.28d {+07h 41m 08s}  +21.40d {+21d 24' 09"}
SUN_DIST:        113.12 [deg]   Sun_angle= 7.7 [hr] (West of Sun)
MOON_POSTN:      328.27d {+21h 53m 04s}  -18.18d {-18d 11' 02"}
MOON_DIST:        36.41 [deg]
MOON_ILLUM:      93 [%]
GAL_COORDS:       96.34,-60.19 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:        0.00,  0.00 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        WARNING: This Notice was received with 1 (or more) critical values out of range.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 1x1 binning (ie no compression).  
COMMENTS:        All 4 attachments are included.  
COMMENTS:        This notice was forced out after watchdog timer expiring -- most likely due to missing packet(s);  
COMMENTS:        as a consequence some of the fields may be incoorect (eg TRIGGER_NUM,RA,DEC).

GCN Circular #32406
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 220715B, we find an enhanced XRT position of the afterglow: RA, Dec: 254.87517, -33.59793 which is equivalent to:
```
   RA (J2000)  = 16 59 30.04
   Dec (J2000) = -33 35 52.5
```
with an uncertainty of 1.9 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1116441.
Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
GCN Circular #32407
V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (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 (Irkutsk State University, API),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)
MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB 220715B ( E. Troja et al., GCN 32405) errorbox 3230 sec after notice time and 3257 sec after trigger time at 2022-07-15 23:18:59 UT, with upper limit up to 15.1 mag. The observations began at zenith distance = 34 deg. The sun altitude is -18.7 deg.
The galactic latitude b = 5 deg., longitude l = 351 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2032406
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    3347 |         MASTER-OAFA |   C |   180 | 13.0 |        
    3746 |         MASTER-OAFA |   C |   180 | 14.5 |        
    3957 |         MASTER-OAFA |   C |   180 | 14.3 |        
    4168 |         MASTER-OAFA |   C |   180 | 13.5 |        
    4379 |         MASTER-OAFA |   C |   180 | 14.8 |        
    5784 |         MASTER-OAFA |   C |   180 | 15.1 |        
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #32408
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, R. Sanchez-Ramirez, I. Perez-Garcia (IAA-CSIC), C. Perez del Pulgar, A. Castellon, M. A. Castro Tirado (Univ. de Malaga), R. Fernandez-Munoz (IHSM/UMA-CSIC), M. Jelinek (ASU-CAS) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:
Following the detection of GRB 220715B by both Swift (Troja et al., GCNC 32405) and Fermi (GBM team., GCNC 32404), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva, Spain) automatically responded to this burst on Jul. 15 at 22:25:39 UT (i.e. ~57 s after trigger). In the co-added frame (30 x 10 s, clear filter), no source is detected within the enhanced XRT position (Evans et al., GCNC 32406) down to 16.1 mag.
Later on, the 0.6m BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain) automatically pointed to the burst position at 22:26:07 UT (i.e. ~85 s after trigger). In the co-added image (25 x 10 s, clear filter), no optical afterglow is detected within the enhanced XRT position (Evans et al., GCNC 32406) down to 18.4 mag.
We note the expected high galactic extinction towards the burst location, in the direction of the Galactic Bulge.
We thank the staff at INTA-CEDEA and IHSM/UMA-CSIC La Mayora for their excellent support.
GCN Circular #32409
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 1379 s of XRT Photon Counting mode data and 1 UVOT images for GRB 220715B, 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 = 254.87532, -33.59775 which is equivalent to:
```
RA (J2000): 16h 59m 30.08s
Dec (J2000): -33d 35' 51.9"
```
with an uncertainty of 2.5 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 #32410
N. P. M. Kuin (UCL-MSSL) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220715B 103 s after the BAT trigger (Troja et al., GCN Circ. 32405). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 32409) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           103          253          147         >20.1
u_FC               316          565          246         >20.0
white              103         1369          373         >20.4
v                  645         1419           97         >18.9
b                  571         5005          274         >20.8
u                  316         1488          319         >20.1
w1                 695         1468           78         >18.8
m2                 670         1443           97         >19.8
w2                 621         5144          227         >19.9
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.525 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #32411
V. D'Elia (SSDC & INAF-OAR), A. D'Ai (INAF-IASFPA), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB) and E. Troja report on behalf of the Swift-XRT team:
We have analysed 6.4 ks of XRT data for GRB 220715B (Troja et al. GCN Circ. 32405), from 106 s to 29.2 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 32406).
The light curve can be modelled with a power-law decay with a decay index of alpha=0.75 (+/-0.06).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.6 (+0.5, -0.4). The best-fitting absorption column is 1.0 (+0.4, -0.3) x 10^22 cm^-2, in excess of the Galactic value of 3.6 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (1.1 x 10^-10) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.0 (+0.4, -0.3) x 10^22 cm^-2
Galactic foreground: 3.6 x 10^21 cm^-2
Excess significance: 3.2 sigma
Photon index:	     2.6 (+0.5, -0.4)
```
If the light curve continues to decay with a power-law decay index of 0.75, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (5.3 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/01116441.
This circular is an official product of the Swift-XRT team.
GCN Circular #32412
O.J. Roberts (USRA), S. Poolakkil (UAH) and C.Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 22:24:42.74 UT on 15 July 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220715B (trigger 679616687 / 220715934), which was also detected by the Swift/BAT (E. Troja et al. 2022, GCN 32405)
The Fermi GBM Final Real-time Localization (GCN 32404) is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 69 degrees.
The GBM light curve consists of multiple peaks with a duration (T90) of about 40 s (50-300 keV). The time-averaged spectrum from T0-1.024 s to T0+43.008 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.09 +/- 0.23 and the cutoff energy, parameterized as Epeak, is 118 +/- 28 keV.
The event fluence (10-1000 keV) in this time interval is (2.2 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.8 s in the 10-1000 keV band is 2.5 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular #32414
A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), M. Stamatikos (OSU), E. Troja (NASA/GSFC/UMCP), (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 220715B (trigger #1116441) (Troja, et al., GCN Circ. 32405). The BAT ground-calculated position is RA, Dec = 254.860, -33.586 deg which is
```
   RA(J2000)  =  16h 59m 26.5s
   Dec(J2000) = -33d 35' 10.3"
```
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 95%. The mask-weighted light curve shows an initial pulse with a FRED shape, Beginning at just before T+0 and extending to about T+20. There is a second weaker, softer pulse centered just after T+40 sec. There are a few gaps in the light curve data, but none appear to correspond to burst activity. T90 (15-350 keV) is 40.40 +- 1.24 sec (estimated error including systematics). The time-averaged spectrum from T-0.15 to T+42.17 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.36 +- 0.11. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.08 sec in the 15-150 keV band is 1.3 +- 0.2 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/1116441/BA/
GCN Circular #32422
K. Noonan (UVI), P. Gokuldass (Florida Institute of Technology), N. Orange (OrangeWave Innovative Science, LLC), K. Smith (UVI), R. Querrard (UVI), D. Morris (UVI) report:
We observed the field of GRB220715B (Fermi GRB team, GCN 32404; and Troja et al., GCN 32405) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin Islands' Etelman Observatory on 07-16-2022 starting at 00:06:54 UT (T+1.7 hrs). We performed a series of exposures in the R filter with a total exposure of 3910 s. The weather conditions were partly cloudy during the hours of observation with an average airmass of 1.6.
We detect no new source within the enhanced XRT position error circle (Evans et al., GCNC 32406), consistent with other non-detections (Lipunov et al. GCN 32407, Hu et al, GCN 33408; and Kuin et al., GCN 32410) and report the following 5-sigma upper limit:
T_mid ||Exposure ||Filter ||Limit
T+ 3.1 hrs ||3910s ||R ||>19.1
The limit is estimated from comparison to nearby USNO B1 stars and is not corrected for Galactic extinction. The VIRT is still in the commissioning phase.
We acknowledge financial support from NASA MUREP MIRO award 80NSSC21M0001, NASA EPSCoR award 80NSSC19M0060, and NSF EiR award 1901296.This message can be cited.

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Jochen Greiner, last update: 24-Jul-2022 [Disclaimer]