Gamma-ray Burst 210212A

(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 12 Feb 21 04:26:27 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.261d {+04h 49m 03s} (J2000),
                  72.546d {+04h 50m 11s} (current),
                  71.587d {+04h 46m 21s} (1950)
GRB_DEC:          +7.234d {+07d 14' 01"} (J2000),
                  +7.269d {+07d 16' 09"} (current),
                  +7.147d {+07d 08' 50"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       44490 [cnts]    Image_Peak=603 [image_cnts]
TRIGGER_DUR:     16.384 [sec] 
TRIGGER_INDEX:   479     E_range: 25-100 keV
BKG_INTEN:       159677 [cnts]
BKG_TIME:        15821.50 SOD {04:23:41.50} UT
BKG_DUR:         64 [sec]
GRB_DATE:        19257 TJD;    43 DOY;   21/02/12
GRB_TIME:        15918.01 SOD {04:25:18.01} UT
GRB_PHI:         -64.82 [deg]
GRB_THETA:         5.24 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.77 [sigma]
IMAGE_SIGNIF:    7.13 [sigma]
MERIT_PARAMS:     +1  +0  +0  +4  +2  -3  +0  +0 +29  +0 
SUN_POSTN:       326.00d {+21h 44m 00s}  -13.63d {-13d 37' 33"}
SUN_DIST:        107.72 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.27d {+22h 09m 05s}  -16.52d {-16d 31' 16"}
MOON_DIST:       101.87 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       71.76,-15.09 [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 = 255.73,-13.88 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:44:14 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.261d {+04h 49m 03s} (J2000),
                  72.546d {+04h 50m 11s} (current),
                  71.587d {+04h 46m 21s} (1950)
GRB_DEC:          +7.234d {+07d 14' 01"} (J2000),
                  +7.269d {+07d 16' 09"} (current),
                  +7.147d {+07d 08' 50"} (1950)
GRB_DATE:        19257 TJD;    43 DOY;   21/02/12
GRB_TIME:        15918.01 SOD {04:25:18.01} UT
TRIGGER_INDEX:   479
GRB_PHI:         -64.82 [deg]
GRB_THETA:         5.24 [deg]
DELTA_TIME:      1539.00 [sec]
TRIGGER_DUR:     16.384 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.77 [sigma]
IMAGE_SIGNIF:    7.13 [sigma]
LC_URL:          sw01032183000msb.lc
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 18"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.43d {+22h 09m 43s}  -16.47d {-16d 28' 05"}
MOON_DIST:       101.71 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       71.76,-15.09 [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 = 255.73,-13.88 [deg].  
COMMENTS:        The 3rd packet (of 3) was missing in the lightcurve data stream.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:44:20 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.2674d {+04h 49m 04.1s} (J2000),
                  72.5523d {+04h 50m 12.5s} (current),
                  71.5933d {+04h 46m 22.3s} (1950)
GRB_DEC:          +7.2701d {+07d 16' 12.3"} (J2000),
                  +7.3056d {+07d 18' 20.2"} (current),
                  +7.1837d {+07d 11' 01.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       42 [cnts]
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16020.95 SOD {04:27:00.95} UT,   102.9 [sec] since BAT Trigger Time
CENTROID_X:      320.84,  raw= 321  [pixels]
CENTROID_Y:      237.94,  raw= 238  [pixels]
ROLL:            257.93 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -141.79
GRB_POS_XRT_Z:   31.69
IMAGE_URL:       sw01032183000msxps_rw.img
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 18"}
SUN_DIST:        107.72 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.43d {+22h 09m 43s}  -16.47d {-16d 28' 04"}
MOON_DIST:       101.73 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.06,-23.05 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.77,-15.05 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:44:59 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.267d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.229d {+07d 13' 45"} (J2000)
POINT_ROLL:      257.931d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16030.47 SOD {04:27:10.47} UT,   112.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.659
N_STARS:         85
X_OFFSET:        544 [pixels]
Y_OFFSET:        568 [pixels]
X_MAX:           1503 [pixels]
Y_MAX:           1527 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw01032183000msufc0112.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 18"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.44d {+22h 09m 44s}  -16.47d {-16d 27' 57"}
MOON_DIST:       101.71 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:44:10 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.2674d {+04h 49m 04.1s} (J2000),
                  72.5523d {+04h 50m 12.5s} (current),
                  71.5933d {+04h 46m 22.3s} (1950)
GRB_DEC:          +7.2701d {+07d 16' 12.3"} (J2000),
                  +7.3056d {+07d 18' 20.2"} (current),
                  +7.1837d {+07d 11' 01.4"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       42 [cnts]
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16020.95 SOD {04:27:00.95} UT,   102.9 [sec] since BAT Trigger Time
CENTROID_X:      320.84,  raw= 321  [pixels]
CENTROID_Y:      237.94,  raw= 238  [pixels]
ROLL:            257.93 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -141.79
GRB_POS_XRT_Z:   31.69
IMAGE_URL:       sw01032183000msxps_rw.img
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 19"}
SUN_DIST:        107.72 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.43d {+22h 09m 43s}  -16.47d {-16d 28' 06"}
MOON_DIST:       101.73 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.06,-23.05 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.77,-15.05 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:44:00 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.2674d {+04h 49m 04.17s} (J2000),
                  72.5523d {+04h 50m 12.55s} (current),
                  71.5933d {+04h 46m 22.39s} (1950)
GRB_DEC:          +7.2701d {+07d 16' 12.3"} (J2000),
                  +7.3056d {+07d 18' 20.2"} (current),
                  +7.1837d {+07d 11' 01.4"} (1950)
GRB_ERROR:       5.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       9.74e-10 [erg/cm2/sec]
GRB_SIGNIF:      6.48 [sigma]
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16020.95 SOD {04:27:00.95} UT,   102.9 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.19 261.63 243.67
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 19"}
SUN_DIST:        107.72 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.43d {+22h 09m 42s}  -16.47d {-16d 28' 07"}
MOON_DIST:       101.73 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.06,-23.05 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.77,-15.05 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.21 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:45:21 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.267d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.229d {+07d 13' 45"} (J2000)
ROLL:            257.931d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16030.47 SOD {04:27:10.47} UT,   112.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     634796856
X_OFFSET:        889 [pixels]
Y_OFFSET:        1153 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1049
Y_GRB_POS:       1313
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0139.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 18"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.44d {+22h 09m 45s}  -16.47d {-16d 27' 53"}
MOON_DIST:       101.71 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:46:02 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
POINT_ROLL:      257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16188.58 SOD {04:29:48.58} UT,   270.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.792
N_STARS:         55
X_OFFSET:        569 [pixels]
Y_OFFSET:        833 [pixels]
X_MAX:           1528 [pixels]
Y_MAX:           1792 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw01032183000msufc0270.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 17"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.44d {+22h 09m 47s}  -16.46d {-16d 27' 46"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:45:15 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.267d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.229d {+07d 13' 45"} (J2000)
POINT_ROLL:      257.931d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16030.47 SOD {04:27:10.47} UT,   112.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.659
N_STARS:         85
X_OFFSET:        544 [pixels]
Y_OFFSET:        568 [pixels]
X_MAX:           1503 [pixels]
Y_MAX:           1527 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw01032183000msufc0112.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 18"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.44d {+22h 09m 45s}  -16.47d {-16d 27' 54"}
MOON_DIST:       101.71 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:45:37 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.267d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.229d {+07d 13' 45"} (J2000)
ROLL:            257.931d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16030.47 SOD {04:27:10.47} UT,   112.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     634796856
X_OFFSET:        889 [pixels]
Y_OFFSET:        1153 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1049
Y_GRB_POS:       1313
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0139.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 17"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.44d {+22h 09m 46s}  -16.46d {-16d 27' 50"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.08 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:46:24 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
ROLL:            257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16188.58 SOD {04:29:48.58} UT,   270.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     634797015
X_OFFSET:        889 [pixels]
Y_OFFSET:        1153 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1049
Y_GRB_POS:       1313
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0297.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 17"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.45d {+22h 09m 47s}  -16.46d {-16d 27' 42"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:46:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
ROLL:            257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16188.58 SOD {04:29:48.58} UT,   270.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     634797015
X_OFFSET:        889 [pixels]
Y_OFFSET:        1153 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1049
Y_GRB_POS:       1313
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0297.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 17"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.45d {+22h 09m 48s}  -16.46d {-16d 27' 40"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:46:21 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
POINT_ROLL:      257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16188.58 SOD {04:29:48.58} UT,   270.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.792
N_STARS:         55
X_OFFSET:        569 [pixels]
Y_OFFSET:        833 [pixels]
X_MAX:           1528 [pixels]
Y_MAX:           1792 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw01032183000msufc0270.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 17"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.45d {+22h 09m 47s}  -16.46d {-16d 27' 42"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:47:32 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
POINT_ROLL:      257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16791.14 SOD {04:39:51.14} UT,   873.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.878
N_STARS:         129
X_OFFSET:        329 [pixels]
Y_OFFSET:        593 [pixels]
X_MAX:           1768 [pixels]
Y_MAX:           2032 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw01032183000msufc0873.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 16"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.46d {+22h 09m 50s}  -16.46d {-16d 27' 30"}
MOON_DIST:       101.69 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:47:39 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
ROLL:            257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16791.14 SOD {04:39:51.14} UT,   873.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     634797617
X_OFFSET:        888 [pixels]
Y_OFFSET:        1152 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1048
Y_GRB_POS:       1312
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0900.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 16"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.46d {+22h 09m 50s}  -16.46d {-16d 27' 28"}
MOON_DIST:       101.69 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 Circular #29487
E. Troja (NASA/GSFC/UMCP), J. A. Kennea (PSU), N. J. Klingler (PSU), H. A. Krimm (NSF), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), B. Sbarufatti (PSU), M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team:
At 04:25:18 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 210212A (trigger=1032183). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 72.261, +7.234 which is
```
   RA(J2000) = 04h 49m 03s
   Dec(J2000) = +07d 14' 01"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a structure with a duration of about 50 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~6 sec after the trigger.
The XRT began observing the field at 04:27:00.9 UT, 103.0 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source with an enhanced position: RA, Dec 72.2666, 7.2693 which is equivalent to:
```
   RA(J2000)  = 04h 49m 03.99s
   Dec(J2000) = +07d 16' 09.5"
```
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 128 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. No spectrum from the promptly downlinked event data is yet available to determine the column density.
The initial flux in the 2.5 s image was 9.74e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 270 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 0.094.
Burst Advocate for this burst is E. Troja (eleonora.troja 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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:47:48 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
ROLL:            257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16791.14 SOD {04:39:51.14} UT,   873.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     634797617
X_OFFSET:        888 [pixels]
Y_OFFSET:        1152 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1048
Y_GRB_POS:       1312
BINNING_INDEX:   1
IM_URL:          sw01032183000msuni0900.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 16"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.46d {+22h 09m 50s}  -16.46d {-16d 27' 27"}
MOON_DIST:       101.69 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 12 Feb 21 04:47:51 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1032183,   Seg_Num: 0
POINT_RA:         72.269d {+04h 49m 04s} (J2000)
POINT_DEC:        +7.230d {+07d 13' 47"} (J2000)
POINT_ROLL:      257.933d
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16791.14 SOD {04:39:51.14} UT,   873.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.878
N_STARS:         129
X_OFFSET:        329 [pixels]
Y_OFFSET:        593 [pixels]
X_MAX:           1768 [pixels]
Y_MAX:           2032 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw01032183000msufc0873.fits
SUN_POSTN:       326.01d {+21h 44m 03s}  -13.62d {-13d 37' 15"}
SUN_DIST:        107.71 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.46d {+22h 09m 51s}  -16.46d {-16d 27' 26"}
MOON_DIST:       101.69 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.09,-23.07 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       71.76,-15.09 [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 12 Feb 21 04:48:42 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     1032183,   Seg_Num: 0
GRB_RA:           72.2665d {+04h 49m 03.95s} (J2000),
                  72.5514d {+04h 50m 12.33s} (current),
                  71.5924d {+04h 46m 22.18s} (1950)
GRB_DEC:          +7.2693d {+07d 16' 09.4"} (J2000),
                  +7.3048d {+07d 18' 17.3"} (current),
                  +7.1829d {+07d 10' 58.5"} (1950)
GRB_ERROR:       3.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  19257 TJD;    43 DOY;   21/02/12
IMG_START_TIME:  16368.00 SOD {04:32:48.00} UT,   450.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       326.01d {+21h 44m 04s}  -13.62d {-13d 37' 15"}
SUN_DIST:        107.72 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      332.47d {+22h 09m 52s}  -16.46d {-16d 27' 17"}
MOON_DIST:       101.69 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      191.06,-23.05 [deg] galactic lon,lat of the burst
ECL_COORDS:       71.77,-15.05 [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 1.1% < P(seren) < 2.8%.

GCN Circular #29489
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 478 s of XRT Photon Counting mode data and 1 UVOT images for GRB 210212A, 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 = 72.26662, +7.26968 which is equivalent to:
```
RA (J2000): 04h 49m 3.99s
Dec (J2000): +07d 16' 10.8"
```
with an uncertainty of 3.7 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 #29491
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), E. Troja (NASA/GSFC/UMCP), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 210212A (trigger #1032183) (Troja, et al., GCN Circ. 29487). The BAT ground-calculated position is RA, Dec = 72.249, 7.215 deg which is
```
  RA(J2000)  =  04h 48m 59.7s 
  Dec(J2000) = +07d 12' 52.6" 
```
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve showed a broad peak with some underlying structure. It began around T-10 sec, peaked around T+5 sec and returned to background by T+90 sec. T90 (15-350 keV) is 80.0 +- 35.8 sec (estimated error including systematics).
The time-averaged spectrum from T-15.51 to T+80.49 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.85 +- 0.23. The fluence in the 15-150 keV band is 8.0 +- 1.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+7.99 sec in the 15-150 keV band is 0.5 +- 0.1 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/1032183/BA/
GCN Circular #29492
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 210212A 112 s after the BAT trigger (Troja et al., GCN Circ. 29487). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 29489) 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           112          262          147         >20.6
u_FC               271          520          246         >20.3
white              112          930          242         >20.8
v                  600         4588          236         >19.0
b                  526          720           39         >19.3
u                  271          868          285         >20.4
w1                 650         4851           90         >19.1
m2                 626         4793          235         >19.7
w2                  93         4383          245         >19.7
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.094 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #29494
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga), S. Guziy (Univ. of Nikolaev) and D. R. Xiong, Y. F. Fan, J. M. Bai, C. J. Wang, Y. X. Xin, X. H. Zhao (Yunnan Observatories of CAS) on behalf of a larger collaboration, report:
Following the detection of GRB 210212A by Swift (Troja et al. GCNC 29487), the 0.6m BOOTES-4/MET robotic telescope at Lijiang Astronomical Observatory (China) started to gather images after the twilight as soon as it was possible. No new source is detected within the Swift/XRT enhanced position (Beardmore et al. GCNC 29489) down to 19.7 mag in the co-added images (5x60 s, clear filer) starting at 13:11 UT on Feb 12. The non-detection is consistent with the limit reported by Swift/UVOT (Troja et al. GCNC 29487).
We thank the staff at Lijiang observatory for their excellent support.
GCN Circular #29495
A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB) and E. Troja report on behalf of the Swift-XRT team:
We have analysed 6.8 ks of XRT data for GRB 210212A (Troja et al. GCN Circ. 29487), from 109 s to 34.2 ks after the BAT trigger. The data comprise 337 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 29489).
The light curve can be modelled with an initial power-law decay with an index of alpha=2.27 (+0.28, -0.50), followed by a break at T+194 s to an alpha of 3.79 (+0.28, -0.23).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.55 (+0.13, -0.12). The best-fitting absorption column is 1.6 (+0.6, -0.4) x 10^21 cm^-2, consistent with the Galactic value of 1.1 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 4.4 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1.
A summary of the WT-mode spectrum is thus:
```
Total column:	     1.6 (+0.6, -0.4) x 10^21 cm^-2
Galactic foreground: 1.1 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.55 (+0.13, -0.12)
```
If the light curve continues to decay with a power-law decay index of 3.79, the count rate at T+24 hours will be 5.3 x 10^-10 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.3 x 10^-20 (2.6 x 10^-20) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01032183.
This circular is an official product of the Swift-XRT team.
GCN Circular #29496
K. L. Murata, R. Adachi, R. Hosokawa, M. Niwano, F. Ogawa, N. Nakamura, N. Ito, S. Ogata, H. Takamatsu, H. Hara, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 210212A (Troja et al. GCN #29487, Beardmore et al. GCN #29489, Palmer et al. GCN #29491, Kuin et al. GCN #29492, Hu et al. GCN #29494, Tohuvavohu et al. GCN #29495) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan. The observation with a series of 60 sec exposures started at 2021-02-12 08:51:45 UT(4.43 hours after the Swift BAT trigger). We stacked the images with good conditions. We did not find any new point sources within the enhanced Swift XRT circle (Beardmore et al. GCN #29489) in all three bands. We obtained the 5-sigma limits of the stacked images as follows.
```
T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
8.6 13:05:08 5400 g'>18.6, Rc>18.5, Ic>17.8
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
```
We used the 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).
GCN Circular #29497
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University)
MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 210212A ( E. Troja et al., GCN 29487) errorbox 53602 sec after notice time and 53674 sec after trigger time at 2021-02-12 19:19:52 UT, with upper limit up to 18.1 mag. The observations began at zenith distance = 44 deg. The sun altitude is -21.6 deg.
The galactic latitude b = -22 deg., longitude l = 191 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1545497
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   53764 |         MASTER-SAAO |   C |   180 | 18.1 |
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #29498
K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), L. Izzo (DARK/NBI), and A. A. Djupvik (NOT), report on behalf of a larger collaboration:
We observed the field of GRB 210212A (Troja et al., GCN #29487), using the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Starting at 20:05:37 UTC on February 12, i.e. 15.5 hr after trigger, we obtained 3x600s exposures in the r-band. The observations were carried out under good conditions, with seeing around 0.8".
Within the refined Swift/XRT error circle (Beardmore et al., GCN #29489), we detect a faint, extended source with FWHM = 1.5". We measure r = 23.23 +/- 0.12 mag, calibrated against nearby field stars in the Pan-STARRS DR1 catalog. At the same position, we also tentatively detect a source in archival Pan-STARRS images.
This source is potentially the host galaxy of GRB 210212A. However, due to the relatively large uncertainty of the currently available XRT position (3.6"), we estimate a chance probability for this source to be unrelated to the GRB of P = 0.09 based on the formalism by Bloom et al. (2002, AJ, 123, 1111).
GCN Circular #29507
S.Dichiara (UMD, NASA-GSFC) and E. Troja (UMD, NASA-GSFC) report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487) with the Gemini South telescope beginning 2021-02-13 02:16:45 UT, approximately 0.91 days post-burst. We obtained 9x120 s exposures in r-band performed with good weather conditions and at an airmass of 1.5
Within the enhanced Swift-XRT error circle (Beardmore et al., GCN Circ. 29489) we detect a single extended source with r = 23.17 +/- 0.05 AB mag, previously reported as the putative host galaxy (Heintz et al., GCN Circ. 29498).
A weak optical source with r = 25.3 +/- 0.2 AB mag lies at the edge of the XRT error circle, 6 arcsec away from the putative host. We cannot determine whether it is related to the GRB at present time.
Magnitudes are calibrated against the Pan-STARRS DR1 catalog and not corrected for Galactic extinction.
We thank the Gemini South staff for rapidly executing these observations.
GCN Circular #29510
Rahul Gupta, A. Kumar, Dimple, A. Ghosh, A. Aryan, B. Kumar, S. B. Pandey, and K. Misra (ARIES) report:
We observed the field of Swift detected GRB 210212A (Troja et al., GCN 29487) with 1.3m Devasthal Fast Optical Telescope (DFOT) located at Devasthal observatory of Aryabhatta Research Institute of Observational Sciences (ARIES), India. The observations were started on 2021-02-13 at 13:54:09 UT i.e. ~ 1.4 days after the BAT trigger. We have taken multiple frames having an exposure time of 180 s in the R filter. We did not detect any optical afterglow candidate within the Swift/XRT enhanced position (Beardmore et al., GCN 29489).
We obtain the following 3-sigma upper limit in the stacked image.
```
Date Start_UT T_start-T0 (days) Filter  Exp time (s)  Limiting Magnitude

======================================================
2021-02-13 13:54:09   ~1.4          R   180*15      > 22.4
```
The magnitude is not corrected for the Galactic extinction in the direction of the burst. Photometric calibration is performed using the standard stars from the USNO-B1.0 catalogue.
This circular may be cited.
GCN Circular #29522
S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE) report on behalf of GRB IKI FuN:
We observed the field of GRB 210212A (Troja et al., GCN 29487) with AZT-33IK telescope of Sayan observatory (Mondy) starting on 2021-02-12 (UT) 14:39:29, i.e. 0.45 days after GRB trigger and reasonable FWHM of about 2.7". Within enhanced XRT position (Beardmore et al., GCN 29489) we found an object. Preliminary photometry of the object in a combined image is following
```
Date       UT start   t-T0       Filter Exp.    OT    Err.  UL(3sigma)
                       (mid, days)        (s)

2021-02-12 14:39:29   0.44527    R      27*120  22.20 0.28  22.4
```
The photometry is based on the nearby USNO-B1.0 stars
```
USNO-B1.0_id R2
0972-0060540 15.06
0972-0060545 15.99
```
The object could be an afterglow of the GRB 210212A which is not separated from (possible host) galaxy (Heintz et al., GCN 29498; Dichiara et al., GCN 29507).
GCN Circular #29527
P. D'Avanzo, S. Covino, D. Fugazza, A. Melandri (INAF-OAB) on behalf of the REM team, report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487) with the REM 60cm robotic telescope located at the ESO premise of La Silla (Chile). The observations were performed starting on 2021 February 12 at 04:27:01 UT (i.e. 103 seconds after the burst) at airmass 3.5 and were carried in the g, r, i, z, H bands simultaneously.
From a preliminary analysis of the first set of images, obtained at a mid time of t-t0 = 150 s, we find no source at the enhanced XRT position (Beardmore et al., GCN Circ. 29489) down to the following 3sigma magnitude upper limits:
```
g > 18.2
r > 18.3
i > 17.4
z > 16.1
(AB; calibrated against the Pan-STARRS catalogue); 

H > 15.8 
(Vega; calibrated against the 2MASS catalogue). 
```
GCN Circular #29540
S.Dichiara (UMD, NASA-GSFC) and E. Troja (UMD, NASA-GSFC) report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487) using the Large Monolithic Imager (LMI) on the 4.3m Lowell Discovery Telescope (LDT) at Happy Jack, AZ. Observations started on February 19, at 03:55:50 UT (about 7 days after the Swift trigger) with SDSS g, r, i and z filters.
The extended source previously reported by Heintz et al. (GCN Circ. 29498) and Dichiara et al. (GCN Circ. 29507) is detected in all bands. We measure a magnitude of r~23.3 +/- 0.2 AB calibrated against the Pan-STARRS DR1 catalog and not corrected for Galactic extinction. A comparison to earlier epochs shows no significant rebrightening.
We thank the staff of the Lowell Discovery Telescope for assistance with these observations.

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Jochen Greiner, last update: 20-Feb-2021 [Disclaimer]