Gamma-ray Burst 220930A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:12:16 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.737d {+04h 18m 57s} (J2000),
                  65.056d {+04h 20m 13s} (current),
                  64.037d {+04h 16m 09s} (1950)
GRB_DEC:         +13.352d {+13d 21' 06"} (J2000),
                 +13.405d {+13d 24' 20"} (current),
                 +13.231d {+13d 13' 53"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3062 [cnts]    Image_Peak=101 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   155     E_range: 50-350 keV
BKG_INTEN:       11016 [cnts]
BKG_TIME:        40298.04 SOD {11:11:38.04} UT
BKG_DUR:         8 [sec]
GRB_DATE:        19852 TJD;   273 DOY;   22/09/30
GRB_TIME:        40312.12 SOD {11:11:52.12} UT
GRB_PHI:          15.89 [deg]
GRB_THETA:        50.57 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     41.20 [sigma]
IMAGE_SIGNIF:    7.33 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +3  -3  +0  +0 +52  +0 
SUN_POSTN:       186.69d {+12h 26m 44s}   -2.89d {-02d 53' 17"}
SUN_DIST:        121.41 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.84d {+16h 07m 22s}  -22.73d {-22d 43' 30"}
MOON_DIST:       170.19 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.87,-25.42 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       65.21, -7.94 [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 = 212.84,20.28 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:15:20 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.7149d {+04h 18m 51.5s} (J2000),
                  65.0336d {+04h 20m 08.0s} (current),
                  64.0151d {+04h 16m 03.6s} (1950)
GRB_DEC:         +13.3500d {+13d 20' 59.9"} (J2000),
                 +13.4038d {+13d 24' 13.5"} (current),
                 +13.2296d {+13d 13' 46.3"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       91 [cnts]
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40482.14 SOD {11:14:42.14} UT,   170.0 [sec] since BAT Trigger Time
CENTROID_X:      252.93,  raw= 253  [pixels]
CENTROID_Y:      301.62,  raw= 302  [pixels]
ROLL:            85.02 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   8.31
GRB_POS_XRT_Z:   -128.39
IMAGE_URL:       sw01125809000msxps_rw.img
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 20"}
SUN_DIST:        121.43 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.87d {+16h 07m 29s}  -22.73d {-22d 44' 00"}
MOON_DIST:       170.20 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.86,-25.44 [deg] galactic lon,lat of the burst
ECL_COORDS:       65.19, -7.94 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:15:23 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.7149d {+04h 18m 51.5s} (J2000),
                  65.0336d {+04h 20m 08.0s} (current),
                  64.0151d {+04h 16m 03.6s} (1950)
GRB_DEC:         +13.3500d {+13d 20' 59.9"} (J2000),
                 +13.4038d {+13d 24' 13.5"} (current),
                 +13.2296d {+13d 13' 46.3"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       91 [cnts]
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40482.14 SOD {11:14:42.14} UT,   170.0 [sec] since BAT Trigger Time
CENTROID_X:      252.93,  raw= 253  [pixels]
CENTROID_Y:      301.62,  raw= 302  [pixels]
ROLL:            85.02 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   8.31
GRB_POS_XRT_Z:   -128.39
IMAGE_URL:       sw01125809000msxps_rw.img
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 20"}
SUN_DIST:        121.43 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.87d {+16h 07m 29s}  -22.73d {-22d 44' 00"}
MOON_DIST:       170.20 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.86,-25.44 [deg] galactic lon,lat of the burst
ECL_COORDS:       65.19, -7.94 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:15:40 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.737d {+04h 18m 57s} (J2000),
                  65.056d {+04h 20m 13s} (current),
                  64.037d {+04h 16m 09s} (1950)
GRB_DEC:         +13.352d {+13d 21' 06"} (J2000),
                 +13.405d {+13d 24' 20"} (current),
                 +13.231d {+13d 13' 53"} (1950)
GRB_DATE:        19852 TJD;   273 DOY;   22/09/30
GRB_TIME:        40312.12 SOD {11:11:52.12} UT
TRIGGER_INDEX:   155
GRB_PHI:          15.89 [deg]
GRB_THETA:        50.57 [deg]
DELTA_TIME:      32.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     41.20 [sigma]
IMAGE_SIGNIF:    7.33 [sigma]
LC_URL:          sw01125809000msb.lc
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 20"}
SUN_DIST:        121.41 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.88d {+16h 07m 30s}  -22.73d {-22d 44' 02"}
MOON_DIST:       170.19 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.87,-25.42 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       65.21, -7.94 [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 = 212.84,20.28 [deg]

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:15:10 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.7149d {+04h 18m 51.57s} (J2000),
                  65.0336d {+04h 20m 08.06s} (current),
                  64.0151d {+04h 16m 03.62s} (1950)
GRB_DEC:         +13.3500d {+13d 20' 59.9"} (J2000),
                 +13.4038d {+13d 24' 13.5"} (current),
                 +13.2296d {+13d 13' 46.3"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       3.09e-09 [erg/cm2/sec]
GRB_SIGNIF:      9.53 [sigma]
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40482.14 SOD {11:14:42.14} UT,   170.0 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.12 261.62 243.71
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 20"}
SUN_DIST:        121.43 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.87d {+16h 07m 29s}  -22.73d {-22d 43' 57"}
MOON_DIST:       170.20 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.86,-25.44 [deg] galactic lon,lat of the burst
ECL_COORDS:       65.19, -7.94 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.31 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:17:34 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 40"} (J2000)
POINT_ROLL:      85.017d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40491.63 SOD {11:14:51.63} UT,   179.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.841
N_STARS:         15
X_OFFSET:        832 [pixels]
Y_OFFSET:        344 [pixels]
X_MAX:           1791 [pixels]
Y_MAX:           1303 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw01125809000msufc0179.fits
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 22"}
SUN_DIST:        121.47 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.89d {+16h 07m 35s}  -22.74d {-22d 44' 20"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:17:48 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 40"} (J2000)
POINT_ROLL:      85.017d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40491.63 SOD {11:14:51.63} UT,   179.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.841
N_STARS:         15
X_OFFSET:        832 [pixels]
Y_OFFSET:        344 [pixels]
X_MAX:           1791 [pixels]
Y_MAX:           1303 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw01125809000msufc0179.fits
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 22"}
SUN_DIST:        121.47 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.90d {+16h 07m 35s}  -22.74d {-22d 44' 22"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [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 30 Sep 22 11:19:12 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 40"} (J2000)
ROLL:            85.017d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40491.63 SOD {11:14:51.63} UT,   179.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     686229321
X_OFFSET:        1018 [pixels]
Y_OFFSET:        737 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1178
Y_GRB_POS:       897
BINNING_INDEX:   1
IM_URL:          sw01125809000msuni0209.fits
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 24"}
SUN_DIST:        121.47 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.91d {+16h 07m 39s}  -22.74d {-22d 44' 36"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [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 30 Sep 22 11:19:26 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 40"} (J2000)
ROLL:            85.017d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40491.63 SOD {11:14:51.63} UT,   179.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     686229321
X_OFFSET:        1018 [pixels]
Y_OFFSET:        737 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1178
Y_GRB_POS:       897
BINNING_INDEX:   1
IM_URL:          sw01125809000msuni0209.fits
SUN_POSTN:       186.69d {+12h 26m 45s}   -2.89d {-02d 53' 24"}
SUN_DIST:        121.47 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      241.91d {+16h 07m 39s}  -22.74d {-22d 44' 38"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [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 30 Sep 22 11:31:41 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 42"} (J2000)
POINT_ROLL:      85.016d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  41182.16 SOD {11:26:22.16} UT,   870.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.819
N_STARS:         51
X_OFFSET:        458 [pixels]
Y_OFFSET:        177 [pixels]
X_MAX:           1897 [pixels]
Y_MAX:           1616 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw01125809000msufc0870.fits
SUN_POSTN:       186.70d {+12h 26m 47s}   -2.89d {-02d 53' 36"}
SUN_DIST:        121.48 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      242.04d {+16h 08m 09s}  -22.78d {-22d 46' 34"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 30 Sep 22 11:31:55 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1125809,   Seg_Num: 0
POINT_RA:         64.678d {+04h 18m 43s} (J2000)
POINT_DEC:       +13.345d {+13d 20' 42"} (J2000)
POINT_ROLL:      85.016d
IMG_START_DATE:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  41182.16 SOD {11:26:22.16} UT,   870.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.819
N_STARS:         51
X_OFFSET:        458 [pixels]
Y_OFFSET:        177 [pixels]
X_MAX:           1897 [pixels]
Y_MAX:           1616 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw01125809000msufc0870.fits
SUN_POSTN:       186.70d {+12h 26m 47s}   -2.89d {-02d 53' 36"}
SUN_DIST:        121.48 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      242.04d {+16h 08m 10s}  -22.78d {-22d 46' 36"}
MOON_DIST:       170.21 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.84,-25.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       65.15, -7.94 [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 30 Sep 22 11:32:37 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     1125809,   Seg_Num: 0
GRB_RA:           64.7169d {+04h 18m 52.05s} (J2000),
                  65.0356d {+04h 20m 08.54s} (current),
                  64.0171d {+04h 16m 04.10s} (1950)
GRB_DEC:         +13.3494d {+13d 20' 57.8"} (J2000),
                 +13.4032d {+13d 24' 11.3"} (current),
                 +13.2290d {+13d 13' 44.2"} (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:  19852 TJD;   273 DOY;   22/09/30
IMG_START_TIME:  40975.00 SOD {11:22:55.00} UT,   662.9 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       186.70d {+12h 26m 47s}   -2.89d {-02d 53' 37"}
SUN_DIST:        121.44 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
MOON_POSTN:      242.05d {+16h 08m 11s}  -22.78d {-22d 46' 43"}
MOON_DIST:       170.20 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:      180.86,-25.44 [deg] galactic lon,lat of the burst
ECL_COORDS:       65.19, -7.94 [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 Circular #32603
S. B. Cenko (GSFC), A. P. Beardmore (U Leicester), C. Gronwall (PSU), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), K. L. Page (U Leicester) and T. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil Gehrels Swift Observatory Team:
At 11:11:52 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220930A (trigger=1125809). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 64.737, +13.352 which is
```
   RA(J2000) = 04h 18m 57s
   Dec(J2000) = +13d 21' 06"
```
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 20 sec and a secondary peak at about 70 seconds after the trigger time. The peak count rate was ~3000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 11:14:42.1 UT, 170.0 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 64.7149, 13.3500 which is equivalent to:
```
   RA(J2000)  = 04h 18m 51.58s
   Dec(J2000) = +13d 21' 00.0"
```
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 77 arcseconds from the BAT onboard position, within the BAT error circle. 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 3.09e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 179 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 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.639.
Burst Advocate for this burst is S. B. Cenko (brad.cenko 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 #32604
Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L. Becerra (UNAM), Simone Dichiara (PSU), Tzveti Dimitrova (ASU), Oc�lotl L�pez (UNAM), Diego Gonz�lez (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita Pereyra (UNAM), Eleonora Troja (UTV/ASU) and report:
We observed the field of the Swift/BAT GRB 220930A (Cenko, GCN Circ. 32603) with the COATLI 50-cm telescope and HUITZI f/8 imager at the Observatorio Astron�mico Nacional on the Sierra de San Pedro M�rtir (http://coatli.astroscu.unam.mx) from 2022-09-30 11:22 UTC to 11:59 UTC (10.5 to 48 minutes after the trigger), obtaining a total of 1920 seconds of exposure in the r filter.
We do not detect any uncataloged sources in the XRT error region (Cenko, GCN Circ. 32603) to a 3-sigma limit of r = 22.5.
Our photometry is calibrated against the Pan-STARRS1 catalog, are on an approximate AB system, and are not corrected for Galactic extinction in the direction of the GRB.
We thank the COATLI/HUITZI technical team and the staff of the Observatorio Astron�mico Nacional.
GCN Circular #32605
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 220930A, we find an enhanced XRT position of the afterglow: RA, Dec: 64.71723, 13.34924 which is equivalent to:
```
   RA (J2000)  = 04 18 52.14
   Dec (J2000) = +13 20 57.3
```
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/1125809.
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 #32606
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar and I. Carrasco (UMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:
Following the detection of GRB 220930A by Swift (Cenko et al. GCNC 32603), the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) observed the GRB location starting on Sep. 30, 11:13:05 UT (~ 73 s after trigger). In the early co-added image (18 x 10 s exposures in the clear filter), no optical afterglow is detected within the enhanced Swift/XRT error region (Evans et al. GCNC 32605) down to 21.0 mag, which is consistent with the limits reported by UVOT (Cenko et al. GCNC 32603) and COATLI (Watson et al. GCNC 32604).
We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.
GCN Circular #32607
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-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the Swift GRB 220930A ( S. B. Cenko et al., GCN 32603) errorbox 11539 sec after notice time and 11568 sec after trigger time at 2022-09-30 14:24:40 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 69 deg. The sun altitude is -41.3 deg.
The galactic latitude b = -25 deg., longitude l = 181 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2105765
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   11659 |         MASTER-Amur |   C |   180 | 19.3 |        
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #32608
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 892 s of XRT Photon Counting mode data and 1 UVOT images for GRB 220930A, 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 = 64.71717, +13.34902 which is equivalent to:
```
RA (J2000): 04h 18m 52.12s
Dec (J2000): +13d 20' 56.5"
```
with an uncertainty of 2.2 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 #32609
A. Belles (PSU) and S. B. Cenko (GSFC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220930A 180 s after the BAT trigger (Cenko et al., GCN Circ. 32603). No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 32608) 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

wh_FC              180          330          147            >20.71
u_FC               338          588          245            >19.95
wh                 618         1368          225            >20.93
v                  669         1418           97            >18.73
b                  594         1343           77            >19.59
u                  744         1318           58            >18.99
w1                 719         1467           77            >18.83
m2                 693         1442           77            >18.59
w2                 644         1393           97            >19.10
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.639 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #32610
R. Strausbaugh (University of Minnesota), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:
We observed the Swift GRB 220930A (Cenko et al., GCN 32603) field with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on October 1, from 00:42 to 01:24 (corresponding to 13.52 to 14.22 hours from the GRB trigger time) with the SDSS i and r filters.
We performed a series of 3x300s exposures in i and r bands. We do not detect any uncatalogued sources in the XRT enhanced error region (Evans et al., GCN 32608), in either band, consistent with other optical upper limits (Watson et al., GCN 32604; Hu et al., GCN 32606; Belles et al., GCN 32609).
The following upper limits are calculated using the Pan-STARRS catalog as reference:
```
r > 22.08
i > 21.73
```
These magnitudes are not corrected for galactic extinction.
GCN Circular #32611
V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), D.N. Burrows (PSU), J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. D'Ai (INAF-IASFPA) and S.B. Cenko report on behalf of the Swift-XRT team:
We have analysed 6.9 ks of XRT data for GRB 220930A (Cenko et al. GCN Circ. 32603), from 160 s to 35.9 ks after the BAT trigger. The data comprise 390 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN Circ. 32605).
The late-time light curve (from T0+5.1 ks) can be modelled with a power-law decay with a decay index of alpha=1.28 (+/-0.11).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.59 (+/-0.08). The best-fitting absorption column is 4.9 (+0.6, -0.5) x 10^21 cm^-2, in excess of the Galactic value of 2.8 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.82 (+0.16, -0.15) and a best-fitting absorption column of 6.4 (+1.2, -1.1) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.7 x 10^-11 (7.3 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     6.4 (+1.2, -1.1) x 10^21 cm^-2
Galactic foreground: 2.8 x 10^21 cm^-2
Excess significance: 5.4 sigma
Photon index:	     1.82 (+0.16, -0.15)
```
If the light curve continues to decay with a power-law decay index of 1.28, the count rate at T+24 hours will be 0.017 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.3 x 10^-13 (1.3 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/01125809.
This circular is an official product of the Swift-XRT team.
GCN Circular #32612
S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), M. Stamatikos (OSU) (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 220930A (trigger #1125809) (Cenko et al., GCN Circ. 32603). The BAT ground-calculated position is RA, Dec = 64.725, 13.353 deg which is
```
   RA(J2000)  =  04h 18m 54.0s
   Dec(J2000) = +13d 21' 12.0"
```
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 11%.
The BAT light curve showed a complex structure with a duration of about 200 sec. T90 (15-350 keV) is 180.47 +- 104.20 sec (estimated error including systematics).
The time-averaged spectrum from T-0.42 to T+235.67 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.59 +- 0.13. The fluence in the 15-150 keV band is 5.5 +- 0.4 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T-0.31 sec in the 15-150 keV band is 6.2 +- 1.0 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/1125809/BA/
GCN Circular #32613
R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 220930A which was also detected by Swift-BAT (Cenko et at., GCN 32603), Swift-XRT (Evans et al., GCN 32608), and Swift/UVOT (Belles et al., GCN 32609).
The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2022-09-30 11:11:52.50 UTC. The measured peak count rate associated with the burst is 435 (+49, -54) counts/s above the background in the combined data of all quadrants, with a total of 1508 (+301, -353) counts. The local mean background count rate was 501 (+3, -3) counts/s. Using cumulative rates, we measure a T90 of 9 (+8, -5) s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2022-09-30 11:11:51.80 UTC. The measured peak count rate is 911 (+80, -88) counts/s above the background in the combined Veto data of all quadrants, with a total of 3694 (+515, -521) counts. The local mean background count rate was 1597 (+6, -7) counts/s. We measure a T90 of 13 (+5, -5) s from the cumulative Veto light curve.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.
GCN Circular #32614
A.Ridnaia, D. Frederiks, A.Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report:
The long-duration GRB 220930A (Swift-BAT detection: Cenko et al., GCN 32603, Barthelmy et al., GCN 32612; AstroSat-CZTI detection: Gopalakrishnan et al., GCN 32613) triggered Konus-Wind at T0=40312.503 s UT (11:11:52.503).
The burst light curve shows a multipeaked structure which starts at ~T0-1.5 s and has a total duration of ~76.0 s. The emission is seen up to ~4 MeV.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB220930_T40312/
As observed by Konus-Wind, the burst had a fluence of 1.78(-0.64,+0.98)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+0.960 s, of 5.39(-2.28,+2.15)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst (measured from T0 to T0+73.984 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.06(-1.06,+1.43), the high energy photon index beta = -2.41(-0.51,+0.46), the peak energy Ep = 198(-58,+181) keV (chi2 = 91/98 dof).
The spectrum near the maximum count rate (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.38(-0.56,+0.66), the high energy photon index beta = -2.25(-1.42,+0.23), the peak energy Ep = 215(-52,+121) keV (chi2 = 97/96 dof).
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN Circular #32617
N. Pankov (IKI), R. Ya. Inasaridze (AbAO), A. Pozanenko (IKI), S. Belkin (IKI, HSE), V. R. Ayvazian (AbAO), D. Datashvili (AbAO), G. V. Kapanadze (AbAO) report on behalf of GRB IKI FuN:
We observed the field of GRB 220930A (Cenko et. al, GCN 32603) with AS-32 telescope of Abastumani Observatory (AbAO). We do not detect any objects within enhanced Swift-XRT error region (Evans et. al, GCN 32608). The 3-sigma upper limit is following:
```
   Date,     UT start, t-T0,    Exp.,  Filter, OT,    Err,  UL(3 sigma)
                      (mid, days)

2022-09-30 22:09:17  0.48085  70*60  R      n/d    n/d    22.3
```
The photometry is based on nearby USNO-B1.0 stars
```
USNO_B10_id  R2
1033-0057261 16.60
1033-0057239 17.39
```
The obtained result is consistent with non-detections reported earlier (Watson et. al, GCN 32604; Hu et al, GCN 32606; Lipunov et al, GCN 32607; Belles and Cenko, GCN 32609; Strausbaugh and Cucchiara, GCN 32610).
GCN Circular #32625
M. Tateda, I.Takahashi, K. L. Murata, Y. Imai, N. Ito, M. Niwano, S. Sato, N. Higuchi, Y. Takamatsu, R. Hosokawa, M. Sasada, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 220930A (S. B. Cenko et al. GCN Circular #32603, Alan M. Watson et al. GCN Circular #32604, The Swift-XRT team GCN Circular #32605,, Y.-D. Hu et al. GCN Circular #32606, V. Lipunov et al. GCN Circular #32607, P.A. Evans et al. GCN Circular #32608, A. Belles et al. GCN Circular #32609, R. Strausbaugh et al. GCN Circular #32610, V. D'Elia et al. GCN Circular #32611, S. D. Barthelmy et al. GCN Circular #32612, R. Gopalakrishnan et al. GCN Circular #32613, A.Ridnaia et al. GCN Circular #32614, N. Pankov et al. GCN Circular #32617) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope Akeno.The observation with a series of 60 sec exposures started at 2022-09-30 13:10:00 UT (118.1 minutes after the Swift/BAT trigger). We stacked the images with good conditions. We did not detect any uncatalogued sources within the enhanced Swift/XRT error region (Evans et al. GCN Circular #32608). We obtained the 5-sigma limits of the stacked images as follows.
```
T0+[days]  | MID-UT | T-EXP[sec] | 5-sigma limits
------------------------------------------------------------------------------------------------
0.23 | 2022-09-30 16:39:02.52 | 14460 | g'>21.0, Rc>20.9, Ic>20.4
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
```
We used PS1 catalog for flux calibration. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire)..

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Jochen Greiner, last update: 03-Oct-2022 [Disclaimer]