Gamma-ray Burst 200729A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 19:39:05 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     984929,   Seg_Num: 0
GRB_RA:          184.375d {+12h 17m 30s} (J2000),
                 184.629d {+12h 18m 31s} (current),
                 183.754d {+12h 15m 01s} (1950)
GRB_DEC:         +45.582d {+45d 34' 56"} (J2000),
                 +45.468d {+45d 28' 05"} (current),
                 +45.860d {+45d 51' 36"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       16144 [cnts]    Image_Peak=386 [image_cnts]
TRIGGER_DUR:     8.192 [sec] 
TRIGGER_INDEX:   490     E_range: 50-350 keV
BKG_INTEN:       110445 [cnts]
BKG_TIME:        70590.63 SOD {19:36:30.63} UT
BKG_DUR:         64 [sec]
GRB_DATE:        19059 TJD;   211 DOY;   20/07/29
GRB_TIME:        70685.09 SOD {19:38:05.09} UT
GRB_PHI:         -158.89 [deg]
GRB_THETA:        41.53 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     9.59 [sigma]
IMAGE_SIGNIF:    8.81 [sigma]
MERIT_PARAMS:     +1  +0  +0  +3  +3  -1  +0  +0 -61  +0 
SUN_POSTN:       129.53d {+08h 38m 08s}  +18.49d {+18d 29' 13"}
SUN_DIST:         52.66 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.59d {+16h 22m 21s}  -19.62d {-19d 37' 16"}
MOON_DIST:        85.34 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.81, 70.35 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      161.38, 42.57 [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:        Galaxy NGC4242 (of total mag=11.00 and dia=4.80 arcmin) is inside the position error circle.  
COMMENTS:        There is a 0.09% probability that an NGC galaxy would happen by chance coincidence.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 239.83,12.03 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 19:40:34 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.414d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.604d {+45d 36' 15"} (J2000)
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70825.50 SOD {19:40:25.50} UT,   140.4 [sec] since BAT Trigger Time
COUNTS:          34    Min_needed= 20
STD_DEV:         38.16   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      3
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        Standard deviation too large.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 19:44:16 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.604d {+45d 36' 15"} (J2000)
POINT_ROLL:      257.806d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70829.95 SOD {19:40:29.95} UT,   144.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.952
N_STARS:         42
X_OFFSET:        612 [pixels]
Y_OFFSET:        336 [pixels]
X_MAX:           1571 [pixels]
Y_MAX:           1295 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00984929000msufc0144.fits
SUN_POSTN:       129.54d {+08h 38m 08s}  +18.49d {+18d 29' 10"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.64d {+16h 22m 33s}  -19.63d {-19d 38' 00"}
MOON_DIST:        85.37 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 19:44:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.604d {+45d 36' 15"} (J2000)
POINT_ROLL:      257.806d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70829.95 SOD {19:40:29.95} UT,   144.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.952
N_STARS:         42
X_OFFSET:        612 [pixels]
Y_OFFSET:        336 [pixels]
X_MAX:           1571 [pixels]
Y_MAX:           1295 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00984929000msufc0144.fits
SUN_POSTN:       129.54d {+08h 38m 08s}  +18.49d {+18d 29' 10"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.64d {+16h 22m 34s}  -19.63d {-19d 38' 03"}
MOON_DIST:        85.37 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 19:46:14 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.604d {+45d 36' 15"} (J2000)
ROLL:            257.806d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70829.95 SOD {19:40:29.95} UT,   144.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     617744455
X_OFFSET:        931 [pixels]
Y_OFFSET:        655 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1091
Y_GRB_POS:       815
BINNING_INDEX:   1
IM_URL:          sw00984929000msuni0170.fits
SUN_POSTN:       129.54d {+08h 38m 09s}  +18.49d {+18d 29' 08"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.66d {+16h 22m 38s}  -19.64d {-19d 38' 17"}
MOON_DIST:        85.38 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [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:     Wed 29 Jul 20 19:46:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.604d {+45d 36' 15"} (J2000)
ROLL:            257.806d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70829.95 SOD {19:40:29.95} UT,   144.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     617744455
X_OFFSET:        931 [pixels]
Y_OFFSET:        655 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1091
Y_GRB_POS:       815
BINNING_INDEX:   1
IM_URL:          sw00984929000msuni0170.fits
SUN_POSTN:       129.54d {+08h 38m 09s}  +18.49d {+18d 29' 08"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.66d {+16h 22m 38s}  -19.64d {-19d 38' 19"}
MOON_DIST:        85.38 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:01:36 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     984929,   Seg_Num: 0
GRB_RA:          184.3790d {+12h 17m 30.95s} (J2000),
                 184.6335d {+12h 18m 32.03s} (current),
                 183.7587d {+12h 15m 02.09s} (1950)
GRB_DEC:         +45.5943d {+45d 35' 39.4"} (J2000),
                 +45.4801d {+45d 28' 48.3"} (current),
                 +45.8720d {+45d 52' 19.2"} (1950)
GRB_ERROR:       3.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  71044.00 SOD {19:44:04.00} UT,   358.9 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       129.55d {+08h 38m 11s}  +18.48d {+18d 28' 59"}
SUN_DIST:         52.65 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.81d {+16h 23m 14s}  -19.68d {-19d 40' 29"}
MOON_DIST:        85.51 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.79, 70.34 [deg] galactic lon,lat of the burst
ECL_COORDS:      161.37, 42.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is inside galaxy NGC4242 (of total mag=11.00 and dia=4.80 arcmin).  
COMMENTS:        There is a 0.05% probability that this would happen by chance coincidence.  
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 0.11% < P(seren) < 0.58%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:03:45 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.606d {+45d 36' 21"} (J2000)
POINT_ROLL:      257.803d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70988.25 SOD {19:43:08.25} UT,   303.2 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.238
N_STARS:         45
X_OFFSET:        372 [pixels]
Y_OFFSET:        96 [pixels]
X_MAX:           1811 [pixels]
Y_MAX:           1535 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00984929000msufc0303.fits
SUN_POSTN:       129.55d {+08h 38m 12s}  +18.48d {+18d 28' 58"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.83d {+16h 23m 19s}  -19.68d {-19d 40' 48"}
MOON_DIST:        85.52 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:04:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.606d {+45d 36' 21"} (J2000)
POINT_ROLL:      257.803d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70988.25 SOD {19:43:08.25} UT,   303.2 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.238
N_STARS:         45
X_OFFSET:        372 [pixels]
Y_OFFSET:        96 [pixels]
X_MAX:           1811 [pixels]
Y_MAX:           1535 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00984929000msufc0303.fits
SUN_POSTN:       129.55d {+08h 38m 12s}  +18.48d {+18d 28' 58"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.83d {+16h 23m 20s}  -19.68d {-19d 40' 50"}
MOON_DIST:        85.52 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:05:10 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.606d {+45d 36' 21"} (J2000)
ROLL:            257.803d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70988.25 SOD {19:43:08.25} UT,   303.2 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     617744613
X_OFFSET:        931 [pixels]
Y_OFFSET:        655 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1091
Y_GRB_POS:       815
BINNING_INDEX:   1
IM_URL:          sw00984929000msuni0329.fits
SUN_POSTN:       129.55d {+08h 38m 12s}  +18.48d {+18d 28' 57"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.84d {+16h 23m 23s}  -19.68d {-19d 41' 00"}
MOON_DIST:        85.53 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:05:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     984929,   Seg_Num: 0
POINT_RA:        184.413d {+12h 17m 39s} (J2000)
POINT_DEC:       +45.606d {+45d 36' 21"} (J2000)
ROLL:            257.803d
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  70988.25 SOD {19:43:08.25} UT,   303.2 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     617744613
X_OFFSET:        931 [pixels]
Y_OFFSET:        655 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1091
Y_GRB_POS:       815
BINNING_INDEX:   1
IM_URL:          sw00984929000msuni0329.fits
SUN_POSTN:       129.55d {+08h 38m 12s}  +18.48d {+18d 28' 57"}
SUN_DIST:         52.68 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      245.85d {+16h 23m 23s}  -19.68d {-19d 41' 02"}
MOON_DIST:        85.53 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.72, 70.34 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      161.39, 42.61 [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 #28165
P. A. Evans (U Leicester), J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU), K. L. Page (U Leicester), M. H. Siegel (PSU) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Neil Gehrels Swift Observatory Team:
At 19:38:05 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 200729A (trigger=984929). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 184.375, +45.582 which is
```
   RA(J2000) = 12h 17m 30s
   Dec(J2000) = +45d 34' 56"
```
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 40 sec. The peak count rate was ~500 counts/sec (15-350 keV), at ~10 sec after the trigger.
The XRT began observing the field at 19:40:25.5 UT, 140.4 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source located at RA, Dec 184.37782, 45.59380 which is equivalent to:
```
   RA(J2000)  = 12h 17m 30.68s
   Dec(J2000) = +45d 35' 37.7"
```
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This location is 43 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.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.07 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 6.5 (+3.87/-3.22) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 303 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18.0 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.01.
The XRT position is within the extent of the nearby galaxy NGC 4242, for which SIMBAD lists a redshift of 0.00176 (~7.4 Mpc). Follow up observations are strongly encouraged.
Burst Advocate for this burst is P. A. Evans (pae9 AT star.le.ac.uk). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 29 Jul 20 20:25:26 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     984929,   Seg_Num: 0
GRB_RA:          184.3775d {+12h 17m 30.59s} (J2000),
                 184.6320d {+12h 18m 31.67s} (current),
                 183.7572d {+12h 15m 01.73s} (1950)
GRB_DEC:         +45.5938d {+45d 35' 37.6"} (J2000),
                 +45.4796d {+45d 28' 46.5"} (current),
                 +45.8715d {+45d 52' 17.4"} (1950)
GRB_ERROR:       3.5 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  19059 TJD;   211 DOY;   20/07/29
IMG_START_TIME:  71044.00 SOD {19:44:04.00} UT,   358.9 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       129.56d {+08h 38m 15s}  +18.48d {+18d 28' 45"}
SUN_DIST:         52.64 [deg]   Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN:      246.04d {+16h 24m 11s}  -19.73d {-19d 43' 53"}
MOON_DIST:        85.69 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      140.80, 70.34 [deg] galactic lon,lat of the burst
ECL_COORDS:      161.37, 42.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is inside galaxy NGC4242 (of total mag=11.00 and dia=4.80 arcmin).  
COMMENTS:        There is a 0.05% probability that this would happen by chance coincidence.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.11% < P(seren) < 0.58%.

GCN Circular #28166
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),
H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
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-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) was pointed to the Swift GRB 200729A ( P. A. Evans et al., GCN 28165) errorbox 3549 sec after notice time and 3617 sec after trigger time at 2020-07-29 20:38:22 UT, with upper limit up to 15.9 mag. Observations started at twilight. The observations began at zenith distance = 48 deg. The sun altitude is -9.7 deg.
The galactic latitude b = 71 deg., longitude l = 140 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1410562
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    3707 |          MASTER-IAC |  P- |   180 | 15.3 |        
    3946 |          MASTER-IAC |  P- |   180 | 15.9 |        
```
The observation and reduction will continue. The message may be cited.
GCN Circular #28167
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco, A. Reina (Univ. de Malaga) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:
Following the Swift trigger of GRB 200729A (Evans et al., GCNC 28165), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva), southern Spain, automatically responded to this burst. A given number of images were taken starting 19:39:29UT (84 s after trigger) during the twilight. In the co-adding of images taken later on, no source is detected which down to 19.6 mag (clear filter) at the XRT position, in the outskirts of the NGC 4242 galaxy. This is consistent with the non-detection reported by UVOT (Evans et al., GCNC 28165) and MASTER (Lipunov et al., GCNC 28166). Further observations are ongoing.
We thank the staff at INTA-CEDEA for their excellent support.
GCN Circular #28168
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 1504 s of XRT Photon Counting mode data and 1 UVOT images for GRB 200729A, 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 = 184.37626, +45.59476 which is equivalent to:
```
RA (J2000): 12h 17m 30.30s
Dec (J2000): +45d 35' 41.1"
```
with an uncertainty of 1.7 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 #28169
Daniele B. Malesani (DTU Space), Antonio de Ugarte Postigo (HETH, IAA-CSIC; DARK/NBI), Luca Izzo (DARK/NBI), Jens Hjorth (DARK/NBI), D. Alexander Kann (HETH, IAA-CSIC), Christina C. Thoene (HETH, IAA-CSIC), Martin A. Guerrero (IAA-CSIC), report on behalf of a larger collaboration:
We observed the field of GRB 200729A (Evans et al., GCN 28165) with the Nordic Optical Telescope equipped with the ALFOSC imager. Observations were carried out in the r and z filters, and started on 2020 Jul 29.911 UT (2.2 hr after the trigger), as soon as visibility allowed.
Within the XRT position of the candidate afterglow (Osborne et al., GCN 28168), we detect no new sources compared to archival Pan-STARRS images. The 3-sigma limiting magnitudes are:
```
r > 22.5 AB
z > 22.0 AB
```
As noted by Evans et al. (GCN 28165), the location of the X-ray source lies on top of the nearby galaxy NGC 4242, whose distance is ~5.5 Mpc (from Simbad, which however presents values up to 10 Mpc). We note that, if the GRB is associated with NGC 4242, our limit would correspond to an absolute magnitude M_r > -6.2, which, in lack of significant extinction, provides a deep limit to the GRB optical luminosity. For example, the earliest detection of SN 2008D (3.5 hr after the outburst; Soderberg et al. 2008, Nat, 453, 469) had an absolute U-band magnitude M(U) = -12.3 (even before correcting for the significant extinction).
At 5.5 Mpc, the gamma-ray fluence of 8*10^-7 erg cm^-2 (taken from https://gcn.gsfc.nasa.gov/notices_s/984929/BA/) would correspond to 3*10^45 erg - fainter than the low-luminosity events GRB 980425, GRB 170817A, and the X-ray output of SN 2008D.
While the visibility of this target from La Palma is now over, we encourage further observations from other locations.
GCN Circular #28170
P. D'Avanzo (INAF-OAB), V. D'Elia (ASI-SSDC), S. Campana, S. Covino (INAF-OAB), D. Malesani (DTU Space), A. Fiorenzano, A. Garcia de Gurtubai Escudero (INAF-TNG) on behalf of the CIBO collaboration report:
We observed the field of GRB 200729A (Evans et al., GCN Circ. 28165) with the Italian 3.6m TNG telescope equipped with NICS in imaging mode. A series of images were obtained with the J filter on 2020-06-29 from 22:28:28 UT to 22:55:43 UT (i.e. between about 2.8 and 3.3 hours after the burst).
No obvious source is found within the enhanced XRT position (Osborne et al., GCN Circ. 28168) down to a 3-sigma limiting magnitude of J > 19.6 (Vega, calibrated against the 2MASS catalogue).
GCN Circular #28171
T. Laskar (U. of Bath), E. Berger (Harvard), C. Kilpatrick (UCSC), W. Fong, R. Margutti, R. Chornock, A. Hajela, K. Alexander, D. Coppejans (Northwestern) report:
"In an archival observation of NGC4242 by the Spitzer Space Telescope on 2012-08-06 (PI: van Zee), we find a point-like source coincident with the enhanced X-ray position of GRB 200729A (Osborne et al, GCN 28168). Photometry is complicated by the variable background; preliminary analysis suggests the object has a flux density of ~ 11 uJy (21.3 AB mag), about 1 mag brighter than the NOT r/z limits (Malesani et al., GCN 28169).
Further analysis is in progress."
GCN Circular #28172
C. D. Kilpatrick (UCSC), W. Fong, A. Hajela, R. Chornock, T. Laskar, R. Margutti, D. Coppejans, K. D. Alexander, (Northwestern), E. Berger (Harvard) report:
We examined the latest, enhanced XRT position of the long GRB 200729A detected by Swift (Evans et al., GCN 28165) in PAN-STARRS imaging. We downloaded the Pan-STARRS DR1 images and note the presence of a faint source detected within the XRT error circle (90% confidence Osborne et al., GCN 28168) at:
```
RA (J2000) = 12:17:30.32
Dec (J2000) = +45:35:41.4
```
The location of this source is consistent with the pre-burst counterpart detected in Spitzer/IRAC imaging (Laskar et al., GCN 28171). Using a 1.5 arcsec aperture, we measure that the source has i=21.4+/-0.2 mag, y=21.0+/-0.2 mag, and z=21.0+/-0.1 mag. We note that our z-band photometry is 1 magnitude brighter than the limit reported by NOT (Malesani et al., GCN 28169). The source is not obviously detected in either Pan-STARRS g or r-band imaging. The source may be marginally extended, although it is too faint to definitively determine whether the source is intrinsically extended beyond the PSF of the Pan-STARRS DR1 imaging.
Based on the column of neutral hydrogen inferred from the Swift/XRT X-ray spectrum (7.1e21 cm-2; https://www.swift.ac.uk/xrt_unenh_positions/00984929/), the total optical extinction to any counterpart is approximately A_V = 3.7 mag (Guver & Ozel, 2009, MNRAS, 400, 2050). Assuming the Pan-STARRS source is in NGC 4242 with a TRGB distance of 5.3 Mpc (Sabbi et al. 2018, ApJS, 235, 23), any stellar counterpart would have M_i~-9.3 mag, which is extremely luminous for a star even with initial mass > 25 M_sun. Thus the lack of an optical or near-infrared counterpart (Hu et al., GCN 28167; Lipunov et al., GCN 28166; Malesani et al., GCN 28169; D’Avanzo et al., GCN 28170) and large implied luminosity suggests that a supernova or non-terminal outburst from such a star in NGC 4242 is unlikely.
Alternatively, if the source is a background galaxy, and the i-z color represents a 4000 Angstrom break, this places the redshift of the galaxy at z~1.1, which would provide a natural explanation for the faint XRT flux (GCN 28165), and the lack of detected optical or NIR afterglow.
GCN Circular #28173
The IceCube Collaboration (http://icecube.wisc.edu/) reports:
IceCube has performed a search for track-like muon neutrino events arriving from the direction of GRB 200729A (https://gcn.gsfc.nasa.gov/gcn3/28165.gcn3) in a time window one hour in duration, beginning 10 minutes prior to the Swift BAT trigger (2020-07-29 19:28:05 UTC to 2020-07-29 20:28:05 UTC), during which IceCube was collecting good quality data. Zero track-like events are found in spatial coincidence with GRB 200729A during this time period. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 5.5 x 10^-5 TeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum are between approximately 1 TeV and 200 TeV.
The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.
GCN Circular #28174
C. Malacaria (NASA-MSFC/USRA), E. Burns (NASA-GSFC), C. M. Hui (NASA-MSFC) and P. Veres (UAH) report on behalf of the Fermi-GBM team:
At 19:38:05 UT on 29 July 2020, the Swift Burst Alert Telescope (BAT) triggered and located GRB 200729A (Evans et al. 2020, GCN 28165).
There was no Fermi-GBM onboard trigger around the event time of GRB 200729A. An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM also identified no counterpart candidates. The GBM targeted search [1], the most sensitive, coherent search for GRB-like signals, was run from +/-30 s around the GRB 200729A time.
The targeted search identified a transient source with an offset of about 7 s with respect to the Swift-BAT trigger time, consistent with the Swift-BAT light curve peak. The candidate most significant timescale is 8.192 s centered at the offset time, with a log likelihood ratio of 62. The Swift-XRT location is slightly out of the 3 sigma Fermi-GBM contours. However, given the reasonable coincidence of trigger time, light curve peak-time and morphology, this candidate is likely coincident with GRB 200729A. The source spectrum at all significant time scales identified by the search is best fit by a power law function with an exponential high-energy cutoff. The fit was performed between the Fermi-GBM trigger time T0 and T0+33 s. The power law index is 0.70 +/- 0.53, and the cutoff energy, parameterized as Epeak, is 159 +/- 19 keV.
The spectral analysis results presented above are preliminary.
[1] Goldstein et al. 2019 arXiv:1903.12597
GCN Circular #28175
G. S. Anand (Hawaii), R. B. Tully (Hawaii), L. Rizzi (Keck), I. Karachentsev (Special Astrophysical Observatory, Russia), E. Shaya (UMD)
On 2020-07-15 12:14:59, we obtained Hubble Space Telescope imaging of NGC 4242 as part of the Every Known Nearby Galaxy survey (SNAP-15922, PI R. Tully). Our data consists of imaging in F606W (760s) and F814W (760s) bands, which cover the localized region from Swift of GRB 200729A.
Our observations show an extended red source within the 1.7" Swift localization region, which may be a background galaxy. DOLPHOT PSF photometry shows several point sources within the 1.7" region as well, with the two brightest point sources having (F606W, F814W) magnitudes of (23.556, 23.509) and (26.182, 23.833). In our deep CMD, the observed location of the TRGB suggests a distance of ~7.5 Mpc, further than previous TRGB determinations of 5.3 Mpc (Sabbi et al. 2018, ApJS, 235, 23).
Link to color HST image, with background galaxy manually highlighted in red circle: https://gsanand.github.io/ngc4242.jpg
GCN Circular #28176
A. Tohuvavohu (U. Toronto), A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , B. Sbarufatti (PSU), D.N. Burrows (PSU) and P.A. Evans report on behalf of the Swift-XRT team:
We have analysed 6.2 ks of XRT data for GRB 200729A (Evans et al. GCN Circ. 28165), from 144 s to 25.2 ks after the BAT trigger. The data comprise 213 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 28168).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.45 (+/-0.05).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.78 (+0.14, -0.13). The best-fitting absorption column is 7.9 (+1.2, -1.1) x 10^21 cm^-2, in excess of the Galactic value of 1.1 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.35 (+0.22, -0.21) and a best-fitting absorption column of 9.0 (+2.8, -2.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 6.8 x 10^-11 (8.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     9.0 (+2.8, -2.4) x 10^21 cm^-2
Galactic foreground: 1.1 x 10^20 cm^-2
Excess significance: 6.2 sigma
Photon index:	     1.35 (+0.22, -0.21)
```
If the light curve continues to decay with a power-law decay index of 1.45, the count rate at T+24 hours will be 1.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.6 x 10^-14 (9.9 x 10^-14) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00984929.
This circular is an official product of the Swift-XRT team.
GCN Circular #28177
S. R. Oates (U.Birmingham) and P. A. Evans (U. Leicester) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 200729A 145 s after the BAT trigger (Evans et al., GCN Circ. 28165). No optical afterglow is detected above the flux of NGC 4242, consistent with the XRT position (Osborne et al. GCN Circ. 28168), in the initial UVOT exposures. For all filters, we have attempted to subtract off the light of NGC 4242 by measuring the flux at a position offset from the XRT position, but of a similar brightness.
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           145          295          147         >20.0
u_FC               303          553          246         >18.9
white              145          1874         431         >20.0
v                  633          1749         136         >17.6
b                  559          1849         136         >18.7
u                  303          1824         362         >18.9
w1                 682          1799          97         >18.2
m2                 658          1428          39         >17.8
w2                1359          1725          58         >17.8
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #28178
Daniele B. Malesani (DTU Space), Antonio de Ugarte Postigo (HET, IAA-CSIC), Luca Izzo (DARK/NBI), Jens Hjorth (DARK/NBI), D. Alexander Kann (HET, IAA-CSIC), Christina C. Thoene (HET, IAA-CSIC), Martin A. Guerrero (IAA-CSIC), report on behalf of a larger collaboration:
With the availability of the full calibration set, we inspected again the data from our observation of GRB 200729A (Malesani et al., GCN 28169) taken with the Nordic Optical Telescope (NOT). The seeing in our images is 1".
The object mentioned by Kilpatrick et al. (GCN 28172; see also Laskar et al., GCN 28171; Anand et al., GCN 28175) is marginally seen in our z-band image (a stack of 3x200 s exposures, with mean time 2.5 hr after the GRB trigger). Computing forced photometry against nearby stars from the Pan-STARRS catalog (and using a 1.5" radius aperture), we measure z = 22.1 +- 0.3 AB. We also note that the photometry value is sensitive to the chosen aperture size. This measurement is consistent with the preliminary upper limit we reported in GCN 28169.
No clear detection is present in the r-band image, though there is clearly a background of diffuse, patchy emission from NGC 4242 (as also visible in the HST image; Anand et al. GCN 28175).
We downloaded the Pan-STARRS images from https://ps1images.stsci.edu/cgi-bin/ps1cutouts . Using a 1.5" radius aperture, we measure for the object z = 22.5 +- 0.5 AB, which is consistent with our measurement. As a check, we also measure i = 22.45 +- 0.18 AB. Both values are fainter than reported by Kilpatrick et al. (GCN 28172).
In summary, our NOT images provide confirmation for the optical source mentioned by Kilpatrick et al. (GCN 28172), but we do not find any indication for variability compared to the archival magnitudes from the Pan-STARRS survey. As other groups have noted (Kilpatrick et al., GCN 28172; Anand et al., GCN 28175), this object could be a background galaxy unrelated to NGC 4242.
GCN Circular #28179
H. A. Krimm (NSF), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), P. A. Evans (U Leicester), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 200729A (trigger #984929) (Evans et al., GCN Circ. 28165). The BAT ground-calculated position is RA, Dec = 184.360, 45.571 deg which is
```
   RA(J2000)  =  12h 17m 26.5s
   Dec(J2000) = +45d 34' 13.9"
```
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 46%.
The mask-weighted light curve shows a weak pulse that starts at ~T0, peaks at ~T+6 s, and ends at ~T+130 s. T90 (15-350 keV) is 122.0 +- 34.2 sec (estimated error including systematics).
The time-averaged spectrum from T+0.54 to T+136.54 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.96 +- 0.27. The fluence in the 15-150 keV band is 1.6 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+5.54 sec in the 15-150 keV band is 0.7 +- 0.3 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/984929/BA/
GCN Circular #28180
Z.P. Zhu, D. Xu, X. Liu, S.Y. Fu (NAOC), X. Gao (Urumqi No.1 Senior High School), X. Zhang, J.Z. Liu (XAO) report:
We observed the field of GRB 200729A (Evans et al., GCN 28165) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 10x100s frames in the Sloan r-band, starting at 15:51:05 UT on 2020-07-30, i.e., 20.22 hr after the burst.
No optical source is detected in our stacked image at the enhanced XRT position (Osborne et al., GCN 28168), down to a limiting magnitude of r~20.2, calibrated with the nearby PanSTARRS field.
GCN Circular #28181
A. Hajela, K. D. Alexander, R. Margutti (Northwestern), T. Laskar (U. Bath), W. Fong (Northwestern), C. D. Kilpatrick (UCSC), and E. Berger (Harvard) report on behalf of a larger collaboration:
We observed the Swift GRB 200729A (Evans et al., GCN 28165) at a mean frequency of 6 GHz with the Karl G. Jansky Very Large Array (VLA) beginning 2020 July 31 00:06:33.0 UT (1.19 days after the burst). We do not detect radio emission down to a 3-sigma limit of ~23 microJy.
We thank the VLA staff for rapidly approving our DDT and executing these observations.
GCN Circular #28182
A.E. Volvach (CrAO), A. Pozanenko (IKI), L.N. Volvach (CrAO) report on behalf of IKI-GRB-FuN:
We observed the field of GRB 200729A (Evans et al., GCN 28165) with RT-22 telescope at 36.8 GHz starting on July 30 (UT) 14:12:00 i.e. 0.774 days after trigger. We do not detect radio emission in the enhanced XRT position (Osborne et al., GCN 28168). This is in agreement with non detection by VLA (Hajela et al. GCN 28181). Preliminary result of the observations is following.
```
Date       UT-start UT-stop  OT      Upper Limit (2 sigma)
                              mJy     mJy

2019-07-30  14:12   17:24    n/d     0.8
```
GCN Circular #28192
A. Ridnaia, S. Golenetskii, R.Aptekar, D. Frederiks, M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, report:
The long GRB 200729A (Swift trigger #984929: Evans et al., GCN 28165, Krimm et al., GCN 28179; Fermi-GBM Sub-Threshold candidate: Malacaria et al., GCN 28174) was detected by Konus-Wind in the waiting mode.
The burst light curve shows a single emission episode with a duration of ~ 74 s.
The K-W light curve of this burst is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB200729A/
As observed by Konus-Wind, the burst had a fluence of 5.23(-1.00,+1.32)x10^-6 erg/cm2 and a 2.944-s peak flux, measured from ~T0(BAT)+5.8 s, of 2.18(-0.55,+0.66)x10^-7 erg/cm2/s (both in the 20 - 1500 keV energy range).
The K-W 3-channel time-integrated spectrum (from ~T0(BAT) s to ~T0(BAT)+73.5 s) is well described by a cutoff power-law model with alpha = -0.47(-0.3,+0.5) and Ep = 269(-65,+105) keV.
All the quoted errors are estimated at the 1 sigma confidence level. All the presented results are preliminary.

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Jochen Greiner, last update: 02-Aug-2020 [Disclaimer]