Gamma-ray Burst 220117A

(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:     Mon 17 Jan 22 16:20:23 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.578d {+06h 06m 19s} (J2000),
                  91.794d {+06h 07m 11s} (current),
                  91.088d {+06h 04m 21s} (1950)
GRB_DEC:         -28.410d {-28d 24' 35"} (J2000),
                 -28.414d {-28d 24' 48"} (current),
                 -28.403d {-28d 24' 11"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1429 [image_cnts]
TRIGGER_DUR:     80.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        19596 TJD;    17 DOY;   22/01/17
GRB_TIME:        58731.54 SOD {16:18:51.54} UT
GRB_PHI:          84.67 [deg]
GRB_THETA:        32.72 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    11.06 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  +1  +0  +0 +55  +0 
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 39' 01"}
SUN_DIST:        124.07 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.79d {+07h 47m 09s}  +25.28d {+25d 16' 35"}
MOON_DIST:        58.82 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.73,-21.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       92.25,-51.84 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
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 = 125.22,-7.08 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:22:10 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.5726d {+06h 06m 17.4s} (J2000),
                  91.7886d {+06h 07m 09.2s} (current),
                  91.0828d {+06h 04m 19.8s} (1950)
GRB_DEC:         -28.4354d {-28d 26' 07.4"} (J2000),
                 -28.4390d {-28d 26' 20.3"} (current),
                 -28.4289d {-28d 25' 44.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       29 [cnts]
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58883.44 SOD {16:21:23.44} UT,   151.9 [sec] since BAT Trigger Time
CENTROID_X:      322.68,  raw= 323  [pixels]
CENTROID_Y:      302.96,  raw= 303  [pixels]
ROLL:            212.04 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   11.46
GRB_POS_XRT_Z:   36.03
IMAGE_URL:       sw01093592000msxps_rw.img
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 39' 00"}
SUN_DIST:        124.04 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.80d {+07h 47m 13s}  +25.27d {+25d 16' 28"}
MOON_DIST:        58.85 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.75,-21.73 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.24,-51.86 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:22:07 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.5726d {+06h 06m 17.4s} (J2000),
                  91.7886d {+06h 07m 09.2s} (current),
                  91.0828d {+06h 04m 19.8s} (1950)
GRB_DEC:         -28.4354d {-28d 26' 07.4"} (J2000),
                 -28.4390d {-28d 26' 20.3"} (current),
                 -28.4289d {-28d 25' 44.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       29 [cnts]
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58883.44 SOD {16:21:23.44} UT,   151.9 [sec] since BAT Trigger Time
CENTROID_X:      322.68,  raw= 323  [pixels]
CENTROID_Y:      302.96,  raw= 303  [pixels]
ROLL:            212.04 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   11.46
GRB_POS_XRT_Z:   36.03
IMAGE_URL:       sw01093592000msxps_rw.img
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 39' 00"}
SUN_DIST:        124.04 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.80d {+07h 47m 13s}  +25.27d {+25d 16' 28"}
MOON_DIST:        58.85 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.75,-21.73 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.24,-51.86 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:21:57 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.5726d {+06h 06m 17.42s} (J2000),
                  91.7886d {+06h 07m 09.27s} (current),
                  91.0828d {+06h 04m 19.86s} (1950)
GRB_DEC:         -28.4354d {-28d 26' 07.4"} (J2000),
                 -28.4390d {-28d 26' 20.3"} (current),
                 -28.4289d {-28d 25' 44.2"} (1950)
GRB_ERROR:       6.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       6.01e-10 [erg/cm2/sec]
GRB_SIGNIF:      5.38 [sigma]
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58883.44 SOD {16:21:23.44} UT,   151.9 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.16 261.55 243.70
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 39' 00"}
SUN_DIST:        124.04 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.80d {+07h 47m 12s}  +25.27d {+25d 16' 29"}
MOON_DIST:        58.85 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.75,-21.73 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.24,-51.86 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.55 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:22:58 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.578d {+06h 06m 19s} (J2000),
                  91.794d {+06h 07m 11s} (current),
                  91.088d {+06h 04m 21s} (1950)
GRB_DEC:         -28.410d {-28d 24' 35"} (J2000),
                 -28.414d {-28d 24' 48"} (current),
                 -28.403d {-28d 24' 11"} (1950)
GRB_DATE:        19596 TJD;    17 DOY;   22/01/17
GRB_TIME:        58731.54 SOD {16:18:51.54} UT
TRIGGER_INDEX:   20000
GRB_PHI:          84.67 [deg]
GRB_THETA:        32.72 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     80.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    11.06 [sigma]
LC_URL:          sw01093592000msb.lc
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 39' 00"}
SUN_DIST:        124.06 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.81d {+07h 47m 15s}  +25.27d {+25d 16' 25"}
MOON_DIST:        58.83 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.73,-21.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       92.25,-51.84 [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 an image 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 = 125.22,-7.08 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:24:24 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.564d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.442d {-28d 26' 30"} (J2000)
POINT_ROLL:      212.036d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58893.13 SOD {16:21:33.13} UT,   161.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.510
N_STARS:         190
X_OFFSET:        272 [pixels]
Y_OFFSET:        720 [pixels]
X_MAX:           1231 [pixels]
Y_MAX:           1679 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01093592000msufc0161.fits
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 38' 59"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.82d {+07h 47m 18s}  +25.27d {+25d 16' 19"}
MOON_DIST:        58.87 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.74 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.23,-51.87 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:24:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.564d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.442d {-28d 26' 30"} (J2000)
POINT_ROLL:      212.036d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58893.13 SOD {16:21:33.13} UT,   161.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.510
N_STARS:         190
X_OFFSET:        272 [pixels]
Y_OFFSET:        720 [pixels]
X_MAX:           1231 [pixels]
Y_MAX:           1679 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01093592000msufc0161.fits
SUN_POSTN:       299.61d {+19h 58m 26s}  -20.65d {-20d 38' 59"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.83d {+07h 47m 18s}  +25.27d {+25d 16' 19"}
MOON_DIST:        58.87 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.74 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.23,-51.87 [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:     Mon 17 Jan 22 16:25:47 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.564d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.442d {-28d 26' 30"} (J2000)
ROLL:            212.036d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58893.13 SOD {16:21:33.13} UT,   161.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     664129321
X_OFFSET:        706 [pixels]
Y_OFFSET:        900 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       866
Y_GRB_POS:       1060
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0190.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 58"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.84d {+07h 47m 21s}  +25.27d {+25d 16' 14"}
MOON_DIST:        58.87 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.74 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.23,-51.87 [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:     Mon 17 Jan 22 16:25:54 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.564d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.442d {-28d 26' 30"} (J2000)
ROLL:            212.036d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58893.13 SOD {16:21:33.13} UT,   161.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     664129321
X_OFFSET:        706 [pixels]
Y_OFFSET:        900 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       866
Y_GRB_POS:       1060
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0190.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 58"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.84d {+07h 47m 21s}  +25.27d {+25d 16' 13"}
MOON_DIST:        58.87 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.74 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.23,-51.87 [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:     Mon 17 Jan 22 16:27:35 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.578d {+06h 06m 19s} (J2000),
                  91.794d {+06h 07m 11s} (current),
                  91.088d {+06h 04m 21s} (1950)
GRB_DEC:         -28.410d {-28d 24' 35"} (J2000),
                 -28.414d {-28d 24' 48"} (current),
                 -28.403d {-28d 24' 11"} (1950)
GRB_DATE:        19596 TJD;    17 DOY;   22/01/17
GRB_TIME:        58731.54 SOD {16:18:51.54} UT
TRIGGER_INDEX:   20000
GRB_PHI:          84.67 [deg]
GRB_THETA:        32.72 [deg]
DELTA_TIME:      1078.00 [sec]
TRIGGER_DUR:     80.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    11.06 [sigma]
LC_URL:          sw01093592000msb.lc
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 57"}
SUN_DIST:        124.06 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.85d {+07h 47m 25s}  +25.27d {+25d 16' 07"}
MOON_DIST:        58.84 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.73,-21.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       92.25,-51.84 [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 an image 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 = 125.22,-7.08 [deg].  
COMMENTS:        The 3rd packet (of 3) was missing in the lightcurve data stream.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:28:44 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 38"} (J2000)
POINT_ROLL:      212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59052.04 SOD {16:24:12.04} UT,   320.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.508
N_STARS:         190
X_OFFSET:        386 [pixels]
Y_OFFSET:        580 [pixels]
X_MAX:           1345 [pixels]
Y_MAX:           1539 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw01093592000msufc0320.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 57"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.86d {+07h 47m 27s}  +25.27d {+25d 16' 03"}
MOON_DIST:        58.88 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:48:47 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     1093592,   Seg_Num: 0
GRB_RA:           91.5730d {+06h 06m 17.51s} (J2000),
                  91.7890d {+06h 07m 09.36s} (current),
                  91.0832d {+06h 04m 19.96s} (1950)
GRB_DEC:         -28.4379d {-28d 26' 16.4"} (J2000),
                 -28.4415d {-28d 26' 29.4"} (current),
                 -28.4314d {-28d 25' 53.2"} (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:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  58989.00 SOD {16:23:09.00} UT,   257.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       299.63d {+19h 58m 31s}  -20.65d {-20d 38' 47"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      117.05d {+07h 48m 12s}  +25.25d {+25d 14' 45"}
MOON_DIST:        58.93 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.73 [deg] galactic lon,lat of the burst
ECL_COORDS:       92.24,-51.86 [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:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.11% < P(seren) < 0.58%.

GCN Circular #31466
A. Melandri (INAF-OAB), M. G. Bernardini (INAF-OAB), P. D'Avanzo (INAF-OAB), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), K. L. Page (U Leicester), D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII), T. Sbarrato (INAF-OAB) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 16:18:51 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220117A (trigger=1093592). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 91.578, -28.410 which is
```
   RA(J2000) = 06h 06m 19s
   Dec(J2000) = -28d 24' 35"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 65 sec. The peak count rate was ~900 counts/sec (15-350 keV), at ~15 sec after the trigger.
The XRT began observing the field at 16:21:23.4 UT, 151.9 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 91.57277, -28.43760 which is equivalent to:
```
   RA(J2000)  = 06h 06m 17.46s
   Dec(J2000) = -28d 26' 15.4"
```
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 100 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at https://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 2.57 x 10^20 cm^-2 (Willingale et al. 2013).
The initial flux in the 2.5 s image was 6.01e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 161 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 0.029.
Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.inaf.it). 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:     Mon 17 Jan 22 16:35:52 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 39"} (J2000)
POINT_ROLL:      212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59607.97 SOD {16:33:27.97} UT,   876.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.375
N_STARS:         190
X_OFFSET:        146 [pixels]
Y_OFFSET:        340 [pixels]
X_MAX:           1585 [pixels]
Y_MAX:           1779 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01093592000msufc0876.fits
SUN_POSTN:       299.62d {+19h 58m 28s}  -20.65d {-20d 38' 53"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.93d {+07h 47m 43s}  +25.26d {+25d 15' 35"}
MOON_DIST:        58.90 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 17 Jan 22 16:36:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 39"} (J2000)
ROLL:            212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59607.97 SOD {16:33:27.97} UT,   876.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     664130036
X_OFFSET:        705 [pixels]
Y_OFFSET:        899 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       865
Y_GRB_POS:       1059
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0905.fits
SUN_POSTN:       299.62d {+19h 58m 29s}  -20.65d {-20d 38' 53"}
SUN_DIST:        124.02 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.94d {+07h 47m 45s}  +25.26d {+25d 15' 32"}
MOON_DIST:        58.90 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [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:     Mon 17 Jan 22 16:29:50 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 38"} (J2000)
ROLL:            212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59052.04 SOD {16:24:12.04} UT,   320.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     664129480
X_OFFSET:        706 [pixels]
Y_OFFSET:        900 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       866
Y_GRB_POS:       1060
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0349.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 56"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.87d {+07h 47m 30s}  +25.27d {+25d 15' 58"}
MOON_DIST:        58.89 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [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:     Mon 17 Jan 22 16:36:21 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 39"} (J2000)
ROLL:            212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59607.97 SOD {16:33:27.97} UT,   876.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     664130036
X_OFFSET:        705 [pixels]
Y_OFFSET:        899 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       865
Y_GRB_POS:       1059
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0905.fits
SUN_POSTN:       299.62d {+19h 58m 28s}  -20.65d {-20d 38' 53"}
SUN_DIST:        124.02 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.93d {+07h 47m 44s}  +25.26d {+25d 15' 33"}
MOON_DIST:        58.90 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [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:     Mon 17 Jan 22 16:29:56 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 38"} (J2000)
ROLL:            212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59052.04 SOD {16:24:12.04} UT,   320.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     664129480
X_OFFSET:        706 [pixels]
Y_OFFSET:        900 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       866
Y_GRB_POS:       1060
BINNING_INDEX:   1
IM_URL:          sw01093592000msuni0349.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 56"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.87d {+07h 47m 30s}  +25.27d {+25d 15' 58"}
MOON_DIST:        58.89 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [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:     Mon 17 Jan 22 16:29:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 38"} (J2000)
POINT_ROLL:      212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59052.04 SOD {16:24:12.04} UT,   320.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.508
N_STARS:         190
X_OFFSET:        386 [pixels]
Y_OFFSET:        580 [pixels]
X_MAX:           1345 [pixels]
Y_MAX:           1539 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw01093592000msufc0320.fits
SUN_POSTN:       299.61d {+19h 58m 27s}  -20.65d {-20d 38' 57"}
SUN_DIST:        124.03 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.87d {+07h 47m 28s}  +25.27d {+25d 16' 02"}
MOON_DIST:        58.88 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [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:     Mon 17 Jan 22 16:36:10 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     1093592,   Seg_Num: 0
POINT_RA:         91.562d {+06h 06m 15s} (J2000)
POINT_DEC:       -28.444d {-28d 26' 39"} (J2000)
POINT_ROLL:      212.038d
IMG_START_DATE:  19596 TJD;    17 DOY;   22/01/17
IMG_START_TIME:  59607.97 SOD {16:33:27.97} UT,   876.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.375
N_STARS:         190
X_OFFSET:        146 [pixels]
Y_OFFSET:        340 [pixels]
X_MAX:           1585 [pixels]
Y_MAX:           1779 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw01093592000msufc0876.fits
SUN_POSTN:       299.62d {+19h 58m 28s}  -20.65d {-20d 38' 53"}
SUN_DIST:        124.02 [deg]   Sun_angle= -10.1 [hr] (East of Sun)
MOON_POSTN:      116.93d {+07h 47m 44s}  +25.26d {+25d 15' 34"}
MOON_DIST:        58.90 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      234.76,-21.75 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       92.22,-51.87 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN Circular #31467
S.Y. Fu (NAOC), Z.P. Zhu (NAOC,HUST), X. Liu, S.Q. Jiang, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:
We observed the field of GRB 220117A detected by Swift (Melandri et al., GCN 31466) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. Observations automatically started at 16:21:57 UT on 2022-01-17 (i.e., 186 s after the BAT trigger), and a series of 40 s, 60 s, 90 s, 200 s frames were obtained in the Sloan r- and z- filters.
No uncatalogued optical transient is detected in our stacked images at the Swift-XRT position (GCN 31466), down to limiting magnitudes of r~19.6 and z~18.7, calibrated with the nearby PanSTARRS field.
Nevertheless, we note that from PanSTARRS there exists a source at the border of the Swift-XRT error circle at coordinates R.A. (J2000) = 6:06:17.32 and Dec. (J2000) = -28:26:13.07, which has magnitudes of g ~21.51, r~21.05, i~20.99, and z~21.02, rasing the possibility as the host galaxy of the GRB. This sky area is not covered by SDSS and Legacy Survey. SkyMapper covered the sky area with upper limits of r~19.0 and z~19.0, comparable to the NEXT's level. It is thus unclear if the PanSTARRS source is related to the GRB or not.
GCN Circular #31470
V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina, A.Chasovnikov, V.Topolev, V.Grinshpun, 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 (Irkutsk State University, API),
B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez, M.L.H.Rodriguez (INAOE, OAGH)
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (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 220117A ( A. Melandri et al., GCN 31466) errorbox 15547 sec after notice time and 15645 sec after trigger time at 2022-01-17 20:39:37 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 5 deg. The sun altitude is -28.9 deg.
The galactic latitude b = -21 deg., longitude l = 235 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1852619
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   15736 |         MASTER-SAAO |   C |   180 | 17.5 |        
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #31472
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 428 s of XRT Photon Counting mode data and 1 UVOT images for GRB 220117A, 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 = 91.57218, -28.43765 which is equivalent to:
```
RA (J2000): 06h 06m 17.32s
Dec (J2000): -28d 26' 15.5"
```
with an uncertainty of 2.3 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 #31477
J.A. Kennea (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU) and A. Melandri report on behalf of the Swift-XRT team:
We have analysed 7.4 ks of XRT data for GRB 220117A (Melandri et al. GCN Circ. 31466), from 142 s to 51.2 ks after the BAT trigger. The data comprise 98 s in Windowed Timing (WT) mode (the first 8 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 Beardmore et al. (GCN Circ. 31472).
The late-time light curve (from T0+4.3 ks) can be modelled with a power-law decay with a decay index of alpha=1.48 (+0.11, -0.10).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.69 (+/-0.10). The best-fitting absorption column is 1.95 (+0.24, -0.23) x 10^21 cm^-2, in excess of the Galactic value of 2.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.80 (+/-0.11) and a best-fitting absorption column of 4.5 (+2.6, -1.9) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     4.5 (+2.6, -1.9) x 10^20 cm^-2
Galactic foreground: 2.6 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.80 (+/-0.11)
```
If the light curve continues to decay with a power-law decay index of 1.48, the count rate at T+24 hours will be 6.5 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.3 x 10^-13 (2.5 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01093592.
This circular is an official product of the Swift-XRT team.
GCN Circular #31480
J. Palmerio (CNRS, GEPI - Paris Observatory), D. B. Malesani (Radboud Univ. and DAWN/NBI), J. P. U. Fynbo (DAWN/NBI), D. Xu (NAOC), L. Izzo (DARK/NBI), S. Y. Fu (NAOC), Z. P. Zhu (NAOC, HUST), D. A. Kann (IAA/CSIC), N. R. Tanvir (Univ. Leicester) report on behalf of the Stargate collaboration:
We observed the field of GRB 220117A (Melandri et al., GCN 31466) using the ESO VLT UT3 (Melipal) equipped with the X-shooter spectrograph. Our first observations were carried out using the acquisition camera, using the g, r and z filters (3x60 s in each band). Inside the XRT error circle (Beardmore et al., GCN 31472), we detect a new source, not visible in the archival Pan-STARRS images, which we identify as the GRB afterglow. The source is very red, being detected strongly in z, only weakly in r, and completely missing in g. Calibrated against nearby stars from the Pan-STARRS catalog, we measure z = 20.81 +- 0.12 mag and z - r ~ 2.1 mag (all AB magnitudes). The afterglow coordinates are (J2000, 0.2" error):
```
RA = 06:06:17.409
Dec = -28:26:15.78
```
A spectrum was secured covering the wavelength range 3000-21000 AA, and consisting of 4 exposures of 1200 s each. The observation mid time was 2022 Jan 18.15 UT (11.3 hr after the GRB).
In a preliminary reduction, continuum is detected in the red part of the spectrum down to ~7260 AA. We interpret the break as due to Lyman alpha. The absorption system is rather weak and, at the present time, we identify with confidence only the Lyman-alpha trough and the Si II 1260 AA feature, which correspond to a redshift z = 4.961 for GRB 220117A.
We acknowledge excellent support from the ESO observing staff in Paranal, in particular Michael Abdul-Masih, Diego Parraguez, and Jonathan Smoker.
GCN Circular #31481
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:
We observed Swift GRB 220117A (Melandri et al., GCN 31466) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on January 18, from 01:16 to 01:33 UT (corresponding to 6.97 to 7.25 hours from the GRB trigger time) with the Bessel R and I filters.
We performed a series of 3x320s exposures in I band and 1x152s in R band (the planned observations in R were interrupted). We detect the source at the XRT enhanced coordinates (Beardmore et al., GCN 31472) and VLT observations (Palmerio et al., GCN 31480) in I band, but not R band. The following magnitudes and upper limits are calculated using the USNO-B.1 catalog as reference:
```
R>19.14
I=20.64+/-0.30
```
These magnitudes are not corrected for galactic extinction.
R.S. is funded by NSF AST grant #1831682
GCN Circular #31482
A. A. Breeveld (UCL-MSSL) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220117A 162 s after the BAT trigger (Melandri et al., GCN Circ. 31466). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 31472) 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           162          311          147         >20.5
u_FC               320          570          246         >20.0
white              162          998          306         >20.7
v                  650          845           39         >18.4
b                  576          770           39         >19.4
u                  320          744          265         >20.0
w1                 700          720           19         >19.3
m2                 675          869           39         >18.7
w2                 626          821           39         >18.9
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.028 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #31485
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), 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+939 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220117A (trigger #1093592) (Melandri et al., GCN Circ. 31466). The BAT ground-calculated position is RA, Dec = 91.590, -28.402 deg which is
```
   RA(J2000)  =  06h 06m 21.5s
   Dec(J2000) = -28d 24' 08.5"
```
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 26%.
The mask-weighted light curve shows a multi-peaked structure that starts at ~T+15 s and ends at ~T+65 s. The two larger peaks occur at ~T+15 s and ~T+44 s, respectively. T90 (15-350 keV) is 49.81 +- 2.37 sec (estimated error including systematics).
The time-averaged spectrum from T+14.79 to T+66.14 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.84 +- 0.18. 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+14.81 sec in the 15-150 keV band is 1.9 +- 0.4 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/1093592/BA/
GCN Circular #31487
P. Veres (UAH) reports on behalf of the Fermi-GBM Team:
“Swift-BAT detected GRB 220117A at T0=2022-01-17T16:18:51.5 UT (Melandri et al, GCN 31466). There was no Fermi-GBM onboard trigger around the event.
The GBM targeted search [1], the most sensitive, coherent search for GRB-like signals was run from +/-30 s around the BAT trigger time. A transient source was identified whose most significant timescale according to the search is 4.096 s with a false alarm rate of 1.9e-5 Hz, and a location consistent with the Swift-BAT event, using the standard search protocol with a S/N of 11.4. The GBM targeted search event was found with the highest significance with a “soft” spectral template (Band function with Epeak = 70 keV, alpha = -1.9, beta = -3.7).
The GBM light curve consists of multiple overlapping pulses. The time-averaged spectrum from T0 + 11.7 s to T0 + 69.0 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.39 +/- 0.20 and the cutoff energy, parameterized as Epeak, is 40.0 +/- 4.8 keV.
The event fluence (10-1000 keV) in this time interval for the best fitting model is (2.40 +/- 0.17)E-6 erg/cm^2. Using the redshift z=4.961 reported by Palmerio et al. (GCN 31480), we derive an isotropic equivalent energy in the 1-10,000 keV range of (1.56 +/- 0.11)E+53 erg.
This analysis is preliminary.
[1] Goldstein et al. 2019 arXiv:1903.12597 ”
GCN Circular #31488
N. Ito, R. Hosokawa, K. L. Murata, M. Niwano, Y. Imai, Y. Takamatsu, R. Yamaguchi, R. Noto, S. Sato, M. Takaku, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 220117A (A. Melandri et al. GCN Circular #31466, S.Y. Fu et al. GCN Circular #31467, V. Lipunov et al. GCN Circular #31470, A.P. Beardmore et al. GCN Circular #31472, J.A. Kennea et al. GCN Circular #31477, J. Palmerio et al. GCN Circular #31480, R. Strausbaugh et al. GCN Circular #31481, A. A. Breeveld et al. GCN Circular #31482, D. M. Palmer et al. GCN Circular #31485, P. Veres et al. GCN Circular #31487) 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 2022-01-18 10:26:37 UT (18.1 hours after Swift trigger). We stacked the images with good conditions. We did not detect any sources within the XRT error region (A.P. Beardmore et al. GCN Circular #31472). We obtained the 5-sigma limits of the stacked images as follows.
```
T0+[hours] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
21.3 2022-01-18 13:34:36 7740 g'>19.0, Rc>19.5, Ic>19.2
------------------------------------------------------------------------------------------------
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).
GCN Circular #31511
D. Frederiks, A.Lysenko, A. Ridnaya, D. Svinkin, A. Tsvetkova, M. Ulanov, on behalf of the Konus-Wind team; and A. Melandri (INAF-OAB), A.Y. Lien (U Tampa), D.M. Palmer (LANL), S.D. Barthelmy (GSFC), on behalf of the Swift-BAT team, report:
The long GRB 220117A (Swift-BAT trigger #1093592, T0 = T0(BAT)= 16:18:51.546 UT: Melandri et al. GCN 31466; Palmer et al., GCN 31485; Fermi GBM Sub-Threshold Detection: Veres, GCN 31487) was detected by Konus-Wind (KW) in the waiting mode.
A Bayesian block analysis of the KW waiting mode data in the 20-400 keV band reveals a >10 sigma count rate increase over background in the interval from ~T0+10 s to ~T0+50 s. No statistically significant emission has been detected above 400 keV throughout the burst. The KW light curve of this burst is available at http://www.ioffe.ru/LEA/GRBs/GRB220117A/
To derive broad-band spectral parameters of this burst, we performed a joint spectral analysis of the Swift/BAT data (15-150 keV) and the KW 3-channel spectral data (20-1500 keV). A fit to the time-averaged spectrum, measured from T0+10.557 s to T0+48.829 s, by a power law with an exponential cutoff (CPL) model gives a photon index alpha = -1.14 (-0.32,+0.37), and Ep = 71 (-11,+17) keV, chi^2 = 65.0/ 58 dof. The Band GRB function fits this spectrum equally well, with alpha = -1.04 (-0.40,+0.58), Ep = 65 (-14,+20) keV, and beta = -2.59 (-7.41, +0.43), chi^2 = 64.7/57 dof. A fit to a simple power law gives a photon index of 1.89 (-0.08, +0.09), chi^2 = 72.4/ 59 dof.
In the 15-1500 keV band, the total burst fluence, estimated from the Band model, is (2.8 � 0.7)x10^-6 erg/cm^2, and the 2.944 s peak energy flux is (1.7 � 0.4)x10^-7 erg/cm^2/s.
Assuming the redshift z=4.961 (Palmero et al., GCN 31480) and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014), we estimate the isotropic energy release E_iso to (1.26 � 0.31)x10^53 erg, which is consistent with that estimated from the GBM detection (GCN 31487), the isotropic peak luminosity L_iso to (4.5 � 1.2)x10^52 erg/s, and the rest-frame peak energy of the time-integrated spectrum Ep,z to 387(-84,+120) keV. With the obtained estimates, GRB 220117A lies inside 68% prediction bands for both 'Amati' and 'Yonetoku' relations for the sample of >300 long KW GRBs with known redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021), see http://www.ioffe.ru/LEA/GRBs/GRB220117A/GRB220117A_rest_frame.pdf
GCN Circular #31520
A. Volnova (IKI), I. Sokolov (INASAN, KIAM), I. Izvekova (Institute of Physics of NAS, ICAMBR of NAS), A. Shein (INASAN), Y. Markus (Institute of Physics of NAS, ICAMBR NAS), Y. Markelov (KIAM), R. Ya. Inasaridze (AbAO), N. Pankov (HSE), G. Butenko (ICAMBR NAS), S. Belkin (IKI, HSE), A. Pozanenko (IKI) report on behalf of GRB IKI:
We observed the field of GRB 220117A (Melandri et al., GCN 31466) also detected by Fermi GBM Sub-Threshold (Veres, GCN 31487), and Konus-Wind (Frederiks et al. GCN 31511) with Zeiss-2000, Zeiss-600 and K-800 telescopes of Terskol observatory and with AS-32 telescope of Abastumani observatory. Within the enhanced XRT Swift-XRT error circle (Beardmore et al., GCN 31472) we did not find any optical source. In particular we do not find the afterglow reported by Nanshan/NEXT (Fu et al., GCN 31467), VLT (Palmerio et al., GCN 31480), LCO (Strausbaugh et al., GCN 31481). Preliminary upper limits are following
Date UT start t-T0 Filter Exp. OT Err UL(3sigma) Telescope
```
2022-01-17 18:32:01 0.12671 R     90*60  n/d   n/d   19.3 Zeiss-600
2022-01-17 19:41:36 0.16134 R     19*180 n/d   n/d   20.5 Zeiss-2000
2022-01-17 20:53:30 0.20545 R     35*60  n/d   n/d   19.4 AS-32
```
The photometry is based on the nearby PS1 stars.
GCN Circular #31522
A. Nicuesa Guelbenzu, S. Klose (both TLS Tautenburg), and A. Rau (MPE Garching) report:
We observed the field of the short GRB 220117A (Melandri et al., GCN 31466) with GROND mounted at the 2.2m MPG telescope at La Silla Observatory (Chile).
Observations started at 02:55 UT on January 19, about 34.5 hr after the GRB trigger. They were performed at an average seeing of 1.3 arcsec and at an airmass of 1.0.
Inside the XRT error circle (Beardmore et al., GCN 31472), the reported optical transient (Palmerio et al., GCN 31480; Strausbaugh et al., GCN 31481) is not detected anymore down to the following upper limits (AB mags; 3 sigma):
```
g' > 23.2,
r' > 23.4,
i' > 23.0,
J  > 21.4,
H  > 21.1,
K  > 19.3.
```
The given limits are derived based on calibrating the optical images against the Pan-STARRS catalog and the JHK data against 2MASS stars. We thank Sam Kim for excellent support and for performing the observations.

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