Gamma-ray Burst 121123A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:03:45 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.362d {+20h 29m 27s} (J2000),
                 307.539d {+20h 30m 09s} (current),
                 306.674d {+20h 26m 42s} (1950)
GRB_DEC:         -11.860d {-11d 51' 34"} (J2000),
                 -11.816d {-11d 48' 56"} (current),
                 -12.027d {-12d 01' 37"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       27825 [cnts]    Image_Peak=507 [image_cnts]
TRIGGER_DUR:     8.192 [sec] 
TRIGGER_INDEX:   477     E_range: 25-100 keV
BKG_INTEN:       203081 [cnts]
BKG_TIME:        36070.09 SOD {10:01:10.09} UT
BKG_DUR:         64 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36161.29 SOD {10:02:41.29} UT
GRB_PHI:         177.74 [deg]
GRB_THETA:        28.11 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.42 [sigma]
IMAGE_SIGNIF:    8.11 [sigma]
MERIT_PARAMS:     +1  +0  +0  +3  +2  -2  +0  +0 -41  +0 
SUN_POSTN:       239.40d {+15h 57m 37s}  -20.46d {-20d 27' 47"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.61d {+00h 10m 26s}   +5.72d {+05d 42' 56"}
MOON_DIST:        57.50 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.07,-27.06 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      306.75,  6.94 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 89.04,20.33 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:05:32 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.3179d {+20h 29m 16.29s} (J2000),
                 307.4951d {+20h 29m 58.81s} (current),
                 306.6303d {+20h 26m 31.28s} (1950)
GRB_DEC:         -11.8590d {-11d 51' 32.3"} (J2000),
                 -11.8154d {-11d 48' 55.4"} (current),
                 -12.0264d {-12d 01' 35.2"} (1950)
GRB_ERROR:       5.4 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.30e-09 [erg/cm2/sec]
GRB_SIGNIF:      5.91 [sigma]
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36284.34 SOD {10:04:44.34} UT,   123.0 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.22 261.53 243.67
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       239.41d {+15h 57m 37s}  -20.46d {-20d 27' 48"}
SUN_DIST:         65.56 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.62d {+00h 10m 29s}   +5.72d {+05d 43' 15"}
MOON_DIST:        57.56 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.05,-27.02 [deg] galactic lon,lat of the burst
ECL_COORDS:      306.70,  6.95 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.56 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:05:42 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.3179d {+20h 29m 16.2s} (J2000),
                 307.4951d {+20h 29m 58.8s} (current),
                 306.6303d {+20h 26m 31.2s} (1950)
GRB_DEC:         -11.8590d {-11d 51' 32.3"} (J2000),
                 -11.8154d {-11d 48' 55.4"} (current),
                 -12.0264d {-12d 01' 35.2"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       35 [cnts]
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36284.34 SOD {10:04:44.34} UT,   123.0 [sec] since BAT Trigger Time
CENTROID_X:      219.06,  raw= 219  [pixels]
CENTROID_Y:      298.84,  raw= 299  [pixels]
ROLL:            252.73 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   1.98
GRB_POS_XRT_Z:   -199.51
IMAGE_URL:       sw00539358000msxps_rw.img
SUN_POSTN:       239.41d {+15h 57m 37s}  -20.46d {-20d 27' 48"}
SUN_DIST:         65.56 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.62d {+00h 10m 29s}   +5.72d {+05d 43' 17"}
MOON_DIST:        57.56 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.05,-27.02 [deg] galactic lon,lat of the burst
ECL_COORDS:      306.70,  6.95 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:05:51 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.3179d {+20h 29m 16.2s} (J2000),
                 307.4951d {+20h 29m 58.8s} (current),
                 306.6303d {+20h 26m 31.2s} (1950)
GRB_DEC:         -11.8590d {-11d 51' 32.3"} (J2000),
                 -11.8154d {-11d 48' 55.4"} (current),
                 -12.0264d {-12d 01' 35.2"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       35 [cnts]
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36284.34 SOD {10:04:44.34} UT,   123.0 [sec] since BAT Trigger Time
CENTROID_X:      219.06,  raw= 219  [pixels]
CENTROID_Y:      298.84,  raw= 299  [pixels]
ROLL:            252.73 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   1.98
GRB_POS_XRT_Z:   -199.51
IMAGE_URL:       sw00539358000msxps_rw.img
SUN_POSTN:       239.41d {+15h 57m 37s}  -20.46d {-20d 27' 48"}
SUN_DIST:         65.56 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.62d {+00h 10m 30s}   +5.72d {+05d 43' 18"}
MOON_DIST:        57.56 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.05,-27.02 [deg] galactic lon,lat of the burst
ECL_COORDS:      306.70,  6.95 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:25 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.362d {+20h 29m 27s} (J2000),
                 307.539d {+20h 30m 09s} (current),
                 306.674d {+20h 26m 42s} (1950)
GRB_DEC:         -11.860d {-11d 51' 34"} (J2000),
                 -11.816d {-11d 48' 56"} (current),
                 -12.027d {-12d 01' 37"} (1950)
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36161.29 SOD {10:02:41.29} UT
TRIGGER_INDEX:   477
GRB_PHI:         177.74 [deg]
GRB_THETA:        28.11 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     8.192 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.42 [sigma]
IMAGE_SIGNIF:    8.11 [sigma]
LC_URL:          sw00539358000msb.lc
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 48"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 31s}   +5.72d {+05d 43' 24"}
MOON_DIST:        57.52 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.07,-27.06 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      306.75,  6.94 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 89.04,20.33 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:38 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     375357963
GRB_RA:          310.717d {+20h 42m 52s} (J2000),
                 310.889d {+20h 43m 33s} (current),
                 310.050d {+20h 40m 12s} (1950)
GRB_DEC:          -6.967d {-06d 58' 00"} (J2000),
                  -6.920d {-06d 55' 10"} (current),
                  -7.147d {-07d 08' 48"} (1950)
GRB_ERROR:       15.97 [deg radius, statistical plus systematic]
GRB_INTEN:       91 [cnts/sec]
DATA_SIGNIF:     8.40 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         335.00 [deg]
GRB_THETA:        90.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.95
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   1%  Cyg X-1
DETECTORS:       0,0,0, 0,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         70.27 [deg]   Sun_angle= -4.8 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 31s}   +5.72d {+05d 43' 27"}
MOON_DIST:        53.16 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       39.66,-27.91 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      311.24, 10.84 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 346.68,18.77 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:30 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     375357963
GRB_RA:          316.933d {+21h 07m 44s} (J2000),
                 317.124d {+21h 08m 30s} (current),
                 316.192d {+21h 04m 46s} (1950)
GRB_DEC:         -27.717d {-27d 43' 00"} (J2000),
                 -27.664d {-27d 39' 50"} (current),
                 -27.919d {-27d 55' 07"} (1950)
GRB_ERROR:       24.65 [deg radius, statistical plus systematic]
GRB_INTEN:       73 [cnts/sec]
DATA_SIGNIF:     5.00 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         314.00 [deg]
GRB_THETA:        85.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.00
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:     100%  Below horizon
2nd_MOST_LIKELY:   0%  n/a
DETECTORS:       0,0,0, 0,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 48"}
SUN_DIST:         70.19 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 31s}   +5.72d {+05d 43' 25"}
MOON_DIST:        55.16 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       18.57,-40.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      311.17,-10.73 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 346.68,18.77 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:07:10 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      90
TRIGGER_NUM:     375357963
GRB_RA:          307.300d {+20h 29m 12s} (J2000),
                 307.474d {+20h 29m 54s} (current),
                 306.624d {+20h 26m 30s} (1950)
GRB_DEC:          -8.867d {-08d 52' 00"} (J2000),
                  -8.823d {-08d 49' 22"} (current),
                  -9.034d {-09d 02' 02"} (1950)
GRB_ERROR:       8.78 [deg radius, statistical plus systematic]
GRB_INTEN:       192 [cnts/sec]
DATA_SIGNIF:     18.50 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         335.00 [deg]
GRB_THETA:        85.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.02
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   1%  SGR_1806n20
DETECTORS:       0,0,0, 0,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         66.46 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 32s}   +5.73d {+05d 43' 32"}
MOON_DIST:        56.88 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       36.06,-25.73 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      307.42,  9.86 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 346.68,18.77 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:46 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     375357963
GRB_RA:          311.220d {+20h 44m 53s} (J2000),
                 311.393d {+20h 45m 34s} (current),
                 310.550d {+20h 42m 12s} (1950)
GRB_DEC:          -7.850d {-07d 50' 59"} (J2000),
                  -7.803d {-07d 48' 08"} (current),
                  -8.032d {-08d 01' 55"} (1950)
GRB_ERROR:       9.59 [deg radius, statistical only]
DATA_SIGNIF:     9.40 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         334.00 [deg]
GRB_THETA:        90.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         70.46 [deg]   Sun_angle= -4.8 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 32s}   +5.72d {+05d 43' 28"}
MOON_DIST:        52.87 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       39.02,-28.76 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      311.49,  9.85 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:52 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      68
TRIGGER_NUM:     375357963
GRB_RA:          306.500d {+20h 26m 00s} (J2000),
                 306.675d {+20h 26m 42s} (current),
                 305.822d {+20h 23m 17s} (1950)
GRB_DEC:          -9.267d {-09d 16' 00"} (J2000),
                  -9.224d {-09d 13' 25"} (current),
                  -9.431d {-09d 25' 51"} (1950)
GRB_ERROR:       11.45 [deg radius, statistical plus systematic]
GRB_INTEN:       125 [cnts/sec]
DATA_SIGNIF:     12.00 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         335.00 [deg]
GRB_THETA:        85.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.91
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   1%  SGR_1806n20
DETECTORS:       0,0,0, 0,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         65.58 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 32s}   +5.72d {+05d 43' 29"}
MOON_DIST:        57.74 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       35.28,-25.19 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      306.55,  9.66 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 346.68,18.77 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:06:57 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      67
TRIGGER_NUM:     375357963
GRB_RA:          306.570d {+20h 26m 17s} (J2000),
                 306.747d {+20h 26m 59s} (current),
                 305.883d {+20h 23m 32s} (1950)
GRB_DEC:         -11.510d {-11d 30' 35"} (J2000),
                 -11.467d {-11d 28' 01"} (current),
                 -11.675d {-11d 40' 27"} (1950)
GRB_ERROR:       5.02 [deg radius, statistical only]
DATA_SIGNIF:     12.20 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         333.00 [deg]
GRB_THETA:        84.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         64.96 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.63d {+00h 10m 32s}   +5.73d {+05d 43' 30"}
MOON_DIST:        58.19 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.07,-26.21 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      306.07,  7.47 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:07:15 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      89
TRIGGER_NUM:     375357963
GRB_RA:          309.200d {+20h 36m 48s} (J2000),
                 309.380d {+20h 37m 31s} (current),
                 308.502d {+20h 34m 01s} (1950)
GRB_DEC:         -14.660d {-14d 39' 35"} (J2000),
                 -14.615d {-14d 36' 51"} (current),
                 -14.835d {-14d 50' 04"} (1950)
GRB_ERROR:       4.04 [deg radius, statistical only]
DATA_SIGNIF:     16.60 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16254 TJD;   328 DOY;   12/11/23
GRB_TIME:        36360.59 SOD {10:06:00.59} UT
GRB_PHI:         329.00 [deg]
GRB_THETA:        84.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 49"}
SUN_DIST:         66.50 [deg]   Sun_angle= -4.7 [hr] (East of Sun)
MOON_POSTN:        2.64d {+00h 10m 32s}   +5.73d {+05d 43' 33"}
MOON_DIST:        56.58 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       30.98,-29.83 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      307.79,  3.79 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:09:27 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.372d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.842d {-11d 50' 30"} (J2000)
POINT_ROLL:      252.730d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36292.70 SOD {10:04:52.70} UT,   131.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.092
N_STARS:         95
X_OFFSET:        512 [pixels]
Y_OFFSET:        408 [pixels]
X_MAX:           1471 [pixels]
Y_MAX:           1367 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00539358000msufc0131.fits
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 50"}
SUN_DIST:         65.61 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.65d {+00h 10m 37s}   +5.73d {+05d 43' 56"}
MOON_DIST:        57.54 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:10:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.372d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.842d {-11d 50' 30"} (J2000)
POINT_ROLL:      252.730d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36292.70 SOD {10:04:52.70} UT,   131.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.092
N_STARS:         95
X_OFFSET:        512 [pixels]
Y_OFFSET:        408 [pixels]
X_MAX:           1471 [pixels]
Y_MAX:           1367 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00539358000msufc0131.fits
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 50"}
SUN_DIST:         65.61 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.66d {+00h 10m 39s}   +5.74d {+05d 44' 07"}
MOON_DIST:        57.54 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:11:18 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.372d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.842d {-11d 50' 30"} (J2000)
ROLL:            252.730d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36292.70 SOD {10:04:52.70} UT,   131.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     375357902
X_OFFSET:        1135 [pixels]
Y_OFFSET:        674 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1295
Y_GRB_POS:       834
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0141.fits
SUN_POSTN:       239.41d {+15h 57m 38s}  -20.46d {-20d 27' 51"}
SUN_DIST:         65.61 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.67d {+00h 10m 40s}   +5.74d {+05d 44' 16"}
MOON_DIST:        57.55 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:11:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.372d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.842d {-11d 50' 30"} (J2000)
ROLL:            252.730d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36292.70 SOD {10:04:52.70} UT,   131.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     375357902
X_OFFSET:        1135 [pixels]
Y_OFFSET:        674 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1295
Y_GRB_POS:       834
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0141.fits
SUN_POSTN:       239.41d {+15h 57m 39s}  -20.46d {-20d 27' 51"}
SUN_DIST:         65.61 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.67d {+00h 10m 41s}   +5.74d {+05d 44' 22"}
MOON_DIST:        57.56 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:14:59 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     539358,   Seg_Num: 0
GRB_RA:          307.3179d {+20h 29m 16.29s} (J2000),
                 307.4951d {+20h 29m 58.81s} (current),
                 306.6303d {+20h 26m 31.27s} (1950)
GRB_DEC:         -11.8598d {-11d 51' 35.2"} (J2000),
                 -11.8162d {-11d 48' 58.2"} (current),
                 -12.0272d {-12d 01' 38.0"} (1950)
GRB_ERROR:       0.7 [arcsec radius, statistical only]
GRB_MAG:         19.34 +/- 0.17 [mag]
FILTER:          10, White
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36292.00 SOD {10:04:52.00} UT,   130.7 [sec] since BAT Trigger Time
SUN_POSTN:       239.41d {+15h 57m 39s}  -20.46d {-20d 27' 53"}
SUN_DIST:         65.55 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.70d {+00h 10m 47s}   +5.75d {+05d 44' 55"}
MOON_DIST:        57.64 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.05,-27.02 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      306.70,  6.95 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The UVOT position is 2.9 arcsec from the XRT position.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:15:43 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
POINT_ROLL:      252.729d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36450.65 SOD {10:07:30.65} UT,   289.4 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.478
N_STARS:         71
X_OFFSET:        815 [pixels]
Y_OFFSET:        354 [pixels]
X_MAX:           1774 [pixels]
Y_MAX:           1313 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00539358000msufc0289.fits
SUN_POSTN:       239.41d {+15h 57m 39s}  -20.47d {-20d 27' 53"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.70d {+00h 10m 49s}   +5.75d {+05d 45' 03"}
MOON_DIST:        57.59 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:16:18 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
POINT_ROLL:      252.729d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36450.65 SOD {10:07:30.65} UT,   289.4 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.478
N_STARS:         71
X_OFFSET:        815 [pixels]
Y_OFFSET:        354 [pixels]
X_MAX:           1774 [pixels]
Y_MAX:           1313 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00539358000msufc0289.fits
SUN_POSTN:       239.41d {+15h 57m 39s}  -20.47d {-20d 27' 53"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.71d {+00h 10m 50s}   +5.75d {+05d 45' 09"}
MOON_DIST:        57.59 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:17:17 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
ROLL:            252.729d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36450.65 SOD {10:07:30.65} UT,   289.4 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     375358060
X_OFFSET:        1135 [pixels]
Y_OFFSET:        674 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1295
Y_GRB_POS:       834
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0299.fits
SUN_POSTN:       239.41d {+15h 57m 39s}  -20.47d {-20d 27' 54"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.72d {+00h 10m 52s}   +5.76d {+05d 45' 19"}
MOON_DIST:        57.60 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:17:23 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
ROLL:            252.729d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  36450.65 SOD {10:07:30.65} UT,   289.4 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     375358060
X_OFFSET:        1135 [pixels]
Y_OFFSET:        674 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1295
Y_GRB_POS:       834
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0299.fits
SUN_POSTN:       239.41d {+15h 57m 40s}  -20.47d {-20d 27' 54"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.72d {+00h 10m 52s}   +5.76d {+05d 45' 20"}
MOON_DIST:        57.60 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:23:27 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
ROLL:            252.728d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  37030.60 SOD {10:17:10.60} UT,   869.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     375358640
X_OFFSET:        1134 [pixels]
Y_OFFSET:        673 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1294
Y_GRB_POS:       833
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0879.fits
SUN_POSTN:       239.42d {+15h 57m 41s}  -20.47d {-20d 27' 57"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.77d {+00h 11m 04s}   +5.77d {+05d 46' 25"}
MOON_DIST:        57.66 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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:     Fri 23 Nov 12 10:23:40 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
ROLL:            252.728d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  37030.60 SOD {10:17:10.60} UT,   869.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     375358640
X_OFFSET:        1134 [pixels]
Y_OFFSET:        673 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1294
Y_GRB_POS:       833
BINNING_INDEX:   1
IM_URL:          sw00539358000msuni0879.fits
SUN_POSTN:       239.42d {+15h 57m 41s}  -20.47d {-20d 27' 57"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.77d {+00h 11m 04s}   +5.77d {+05d 46' 27"}
MOON_DIST:        57.66 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [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 23 Nov 12 10:22:21 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
POINT_ROLL:      252.728d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  37030.60 SOD {10:17:10.60} UT,   869.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.854
N_STARS:         190
X_OFFSET:        575 [pixels]
Y_OFFSET:        114 [pixels]
X_MAX:           2014 [pixels]
Y_MAX:           1553 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    11
SL_URL:          sw00539358000msufc0869.fits
SUN_POSTN:       239.42d {+15h 57m 40s}  -20.47d {-20d 27' 57"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.76d {+00h 11m 02s}   +5.77d {+05d 46' 13"}
MOON_DIST:        57.65 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 Nov 12 10:22:46 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     539358,   Seg_Num: 0
POINT_RA:        307.371d {+20h 29m 29s} (J2000)
POINT_DEC:       -11.841d {-11d 50' 27"} (J2000)
POINT_ROLL:      252.728d
IMG_START_DATE:  16254 TJD;   328 DOY;   12/11/23
IMG_START_TIME:  37030.60 SOD {10:17:10.60} UT,   869.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.854
N_STARS:         190
X_OFFSET:        575 [pixels]
Y_OFFSET:        114 [pixels]
X_MAX:           2014 [pixels]
Y_MAX:           1553 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    11
SL_URL:          sw00539358000msufc0869.fits
SUN_POSTN:       239.42d {+15h 57m 40s}  -20.47d {-20d 27' 57"}
SUN_DIST:         65.60 [deg]   Sun_angle= -4.5 [hr] (East of Sun)
MOON_POSTN:        2.76d {+00h 11m 03s}   +5.77d {+05d 46' 17"}
MOON_DIST:        57.65 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:       33.09,-27.06 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      306.76,  6.96 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN Circular #13982
E. A. Helder (PSU), S. D. Barthelmy (GSFC), V. D'Elia (ASDC), P. A. Evans (U Leicester), F. E. Marshall (NASA/GSFC), C. J. Mountford (U Leicester), K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of the Swift Team:
At 10:02:41 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 121123A (trigger=539358). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 307.362, -11.860 which is
```
   RA(J2000)  =  20h 29m 27s
   Dec(J2000) = -11d 51' 34"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak structure with a duration of about 25 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 10:04:44.3 UT, 123.0 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 307.3179, -11.8590 which is equivalent to:
```
   RA(J2000)  = +20h 29m 16.30s
   Dec(J2000) = -11d 51' 32.4"
```
with an uncertainty of 5.4 arcseconds (radius, 90% containment). This location is 155 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 1.30e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 131 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	20:29:16.31 = 307.31794
  DEC(J2000) = -11:51:35.4  = -11.85983
```
with a 90%-confidence error radius of about 0.67 arc sec. This position is 3.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.34 with a 1-sigma error of about 0.17. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05.
Burst Advocate for this burst is E. A. Helder (helder AT psu.edu). 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/too.html.)
GCN Circular #13983
X.-H. Zhao (YNAO), C. -J. Wang, J.-R. Mao (KASI/YNAO), J.-M. Bai (YNAO) report on behalf of a larger collaboration:
We observed the field of GRB 121123A (Helder et al., GCN 13982) with 2.4m Gao-Mei-Gu (GMG) telescope. Observations started at ~1.5 hrs after the burst. The optical afterglow of this burst was detected. The preliminary magnitude was R~19.2. observation is on going.
We thank the GMG staff, especially Hong-Yan Gao, and De-Qing Wang for doing these observations.
GCN Circular #13984
V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, D.Denisenko, A.Sankovich Sternberg Astronomical Institute, Moscow State University
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope (MASTER-Net: ht tp://observ.pereplet.ru) located in Blagoveschensk was pointed to the GRB121123A 100 sec after GRB time at 2012-11-23 10:04:21.926 UT. On our first (20s exposure) set we haven`t found optical transient within SWIFT error-box (Helder et. al., GCN13982). The 5-sigma upper limit has been about 16.5 mag The field was observed at large (more than 70 deg.) zenith distance. The message may be cited.
GCN Circular #13985
S. Foley (UCD) reports on behalf of the Fermi GBM Team:
"At 10:06:00.59 UT on 23 November 2012, the Fermi Gamma-Ray Burst Monitor triggered and located the second emission episode of GRB 121123A (trigger 375357963 / 121123421) which was also detected by the Swift/BAT (Helder et al. 2012, GCN 13982, http://gcn.gsfc.nasa.gov/notices_s/sw00539358000msbx.gif). The emission detected by GBM is contemporaneous with the UVOT observation of an afterglow candidate for GRB 121123A reported by Helder et al. The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 85 degrees.
The GBM light curve consists of a single peak with a long tail with a duration (T90) of about 102 s (50-300 keV). The time-averaged spectrum from T0+3.1 s to T0+106.5 s is well fit by a Band function with Epeak = 85 (+/-3) keV, alpha = -0.25 (+/-0.09), and beta = -3.0 (+0.2/-0.3).
The event fluence (10-1000 keV) in this time interval is (2.20 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+32.6 s in the 10-1000 keV band is 4.00 +/- 0.25 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #13986
D. Xu, T. Kruehler, D. Malesani (DARK/NBI), G. Leloudas (OKC Stockholm and DARK/NBI) I. Ilyin (AIP), J. Clasen (NOT), P. Jakobsson (U. Iceland), J. P. U. Fynbo (DARK/NBI) report on behalf of a larger collaboration:
We observed the field of GRB 121123A (Helder et al., GCN 13982) using the 2.5m Nordic Optical Telescope (NOT) equipped with StanCam. Observations started at 20:03:43 UT on 2012-11-23 (i.e., 9.972 hr after the BAT trigger) and 5x300s R-band frames were obtained with mid-time of 10.218 hr post-trigger.
The afterglow is clearly detected in the stacked image at coordinates
```
R.A.(J2000)= 20:29:16.289
Dec.(J2000)=-11:51:35.87
```
with R=19.65+/-0.03 mag, calibrated with the #0781-0714632 star (R1=R2=17.17 mag with a scatter of 0.3 mag) in the USNO B1 catalog.
We note that our measurement is only modestly fainter than the one reported by Zhao et al. (GCN 13983) at 1.5 hr after the BAT trigger, indicating a shallow decay or an irregular light curve.
GCN Circular #13987
S. Guziy (Mykolaiv Nat. Univ.), R. Sanchez-Ramirez (IAA-CSIC), L. Monteagudo Narvion (IAC), O. Lara, M. Jelinek (IAA-CSIC), P. Kubanek (IP AS CR), Y. Fan, X. Zhao, J. Bai, C. Wang, Y. Xin (Yunnan National Astronomical Observatory), Chenzhou Cui (Beijing National Astronomical Observatory), R. Cunniffe, A.J. Castro-Tirado, J.C. Tello and J. Gorosabel (IAA-CSIC), on behalf of a larger collaboration, report:
We have observed the GRB 121123A optical afterglow (GCN 13982, Helder et al.) with the 0.6m BOOTES-4/MET robotic telescope at the Lijiang Astronomical Observatory (China) and with the 0.82m IAC80 telescope (Tenerife, Spain). The afterglow is detected as follows:
```
   Tel.  Date Nov  To-Tgrb Texp  Filter  Mag(Vega)
         UT-start   (hr)    (s)
 --------------------------------------------------------
  BOOTES-4 23.5196  2.43  5x120    r   18.87 +/- 0.15
  BOOTES-4 23.5711  3.66  5x120    r   19.01 +/- 0.15
  IAC80    23.7853  8.80  4x300    I   18.90 +/- 0.12
```
Our measurements confirm the shallow decay reported by Xu et al. (GCN 13986).
GCN Circular #13988
A. Volnova (SAO MSI, IKI), A. Stepura (UAFO), A. Matkin (UAFO), D. Erofeev (UAFO), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 121123A (Helder et al., GCN 13982) with VT-50 (0.5-m) telescope and GAS-250 of UAFO/ISON-Ussuriysk observatory starting on Nov. 23 (UT) 10:10:15, i.e. 6 minutes after burst trigger. We took several unfiltered images of 30 s. We do not detect detect afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983) in a stacked images. Preliminary photometry of a stacked image obtained with VT-50 is based on USNO-B1.0 stars (R2):
```
T_start  T0+,    Filter, exposure, UL (3 sigma)
(UT) mid (d)     (s)

10:10:15 0.02793 none    90x30     18.1
```
GCN Circular #13989
A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), O.M. Littlejohns (U. Leicester) and E.A. Helder report on behalf of the Swift-XRT team:
We have analysed 10 ks of XRT data for GRB 121123A (Helder et al. GCN Circ. 13982), from 129 s to 23.8 ks after the BAT trigger. The data comprise 669 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The refined XRT position is RA, Dec = 307.3183, -11.85898 which is equivalent to:
```
RA (J2000): 20 29 16.39
Dec(J2000): -11 51 32.3
```
with an uncertainty of 3.5 arcsec (radius, 90% confidence).
The late-time light curve (from T0+4.7 ks) can be modelled with a power-law decay with a decay index of alpha=0.50 (+/-0.09).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.448 (+0.023, -0.022). The best-fitting absorption column is 8.9 (+/-0.6) x 10^20 cm^-2, in excess of the Galactic value of 4.0 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.97 (+/-0.11) and a best-fitting absorption column of 5.8 (+2.3, -1.8) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.2 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     5.8 (+2.3, -1.8) x 10^20 cm^-2
Galactic foreground: 4.0 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.97 (+/-0.11)
```
If the light curve continues to decay with a power-law decay index of 0.50, the count rate at T+24 hours will be 0.051 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.8 x 10^-12 (2.1 x 10^-12) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00539358.
This circular is an official product of the Swift-XRT team.
GCN Circular #13990
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), E. A. Helder (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 121123A (trigger #539358) (Helder, et al., GCN Circ. 13982). The BAT ground-calculated position is RA, Dec = 307.334, -11.873 deg, which is
```
   RA(J2000)  =  20h 29m 20.2s 
   Dec(J2000) = -11d 52' 24.3" 
```
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 82%.
The mask-weighted light curve shows the burst starting off at a weak level at ~T-90 sec, with the triggering peak at ~T+10 sec, then a level period until ~T+200 sec with the onset of a large FRED peak extending out to ~T+700 sec. T90 (15-350 keV) is 317 +- 14 sec (estimated error including systematics).
The time-averaged spectrum from T-6.34 to T+419.00 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.96 +- 0.20, and Epeak of 65.0 +- 5.1 keV (chi squared 45.4 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-5 erg/cm2 and the 1-sec peak flux measured from T+232.56 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.78 +- 0.04 (chi squared 101.58 for 57 d.o.f.). 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/539358/BA/
GCN Circular #13991
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 12254 s of XRT Photon Counting mode data and 15 UVOT images for GRB 121123A, 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 = 307.31813, -11.86023 which is equivalent to:
```
RA (J2000): 20h 29m 16.35s
Dec (J2000): -11d 51' 36.8"
```
with an uncertainty of 1.4 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 #13992
S. Schmidl, A. Nicuesa Guelbenzu, S. Klose (all TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 121123A (Swift trigger 539358; Helder et al., GCN 13982; Fermi trigger 375357963 / 121123421; Foley et al., GCN 13985) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG/ESO telescope at La Silla Observatory (Chile).
Observations started at 00:20 UT on Nov 24, about 15 hours after the GRB trigger. They were performed at an average seeing of 1.3" and at an average airmass of 1.9. The optical afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983; Xu et al., GCN 13986; Guziy et al., GCN 13987) is clearly detected in all bands. Based on 1500 s of total exposures in g'r'i'z' and 1200 s in JHK, we measure the following preliminary AB magnitudes at a midtime of 15.25 hrs after the burst:
```
g' = 20.8 +/- 0.1,
r' = 20.3 +/- 0.1,
i' = 19.9 +/- 0.1,
z' = 19.8 +/- 0.1,
J  = 19.2 +/- 0.1,
H  = 18.9 +/- 0.1,
K  = 18.6 +/- 0.2,
```
calibrated against GROND zeropoints and 2MASS stars. The SED can be fit with a power law with a slope of beta = 1.2 +/ -0.1 and a g-band affected by a dropout with a redshift of z = 2.7 +/- 0.3, taking into acount a Galactic reddening along the line of sight of E_(B-V)= 0.05 mag (Schlegel et al.1998). We note that the data can also be fit with a modest host extinction and no dropout-affected g-band. At present we cannot solve this ambiguity.
GCN Circular #14003
S. T. Holland (STScI) and E. A. Helder (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 121123A starting 131 s after the BAT trigger (Helder et al., 2012, GCNC 13982). The refined UVOT position is
```
     RA (J2000)  20:29:16.30  =  307.31792 (deg)
    Dec (J2000) -11:51:35.6   =  -11.85989 (deg)
```
with an estimated uncertainty of 0.44 arcsec (radius, 90% confidence, statistical + systematic). We observe a slow decay of the optical afterglow, consistent with that reported by Xu et al., (2012, GCNC 13986). The afterglow is weakly detected in white at approximately 40 ks after the BAT trigger. However, the UVOT photometry is affected by a bright (B ~ 14 mag) star (USNO B1.0 0781-0714667) located approximately 22 arcsec north of the afterglow, so the late-time behavior of the optical afterglow's light curve requires further analysis. Preliminary UVOT photometry, and 3-sigma upper limits, for the afterglow are presented below.
```
------------------------------------------------------
Filter      TSTART     TSTOP    Exposure     Mag   Err
------------------------------------------------------
white (fc)     131       281         147   19.43  0.15
u (fc)         289       539         246   19.35  0.23
white (fc)     869      1019         147   19.13  0.12
------------------------------------------------------
v              619      1070          58   18.29  0.33
b              546      1169          58   19.12  0.29
u              695      1145          39   18.58  0.32
uvw1           669    18,011        2137  >21.5
uvm2           645    17,104        1376  >21.3
uvw2           595    22,980        1376  >21.5
white          570       590          19  >19.7
------------------------------------------------------
```
The detection in the UVOT u band, combined with the non-detection in the UVOT uvw1 band, is consistent with GRB 121123A having a redshift of approximately 1.5 < z < 3.4.
The quoted magnitudes and upper limits have not been corrected for the Galactic extinction along the line of sight to this burst of E_{B-V} = 0.05 mag (Schlafly et al. 2011, ApJS, 737, 103). The photometry is in the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373).
GCN Circular #14006
T.Yasuda, M. Tashiro, Y. Terada, W. Iwakiri, K. Takahara, M. Asahina, S. Kobayashi, A. Sakamoto, Y. Ishida, H. Ueno, S. Sugimoto (Saitama U.), M. Akiyama, N. Ohmori, E. Mochinaga, M. Yamauchi (Univ. of Miyazaki), K. Yamaoka, Y. E. Nakagawa (Waseda U.), Y. Hanabata, T. Kawano, K. Takaki, R. Nakamura, Y.Tanaka, M. Ohno, Y. Fukazawa (Hiroshima U.), S. Sugita (Nagoya U.), M. Kokubun, T. Takahashi (ISAS/JAXA), Y. Urata, P. Tsai (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo), on behalf of the Suzaku WAM team, report:
The long GRB 121123A (Helder et al., GCN 13982; Zhao et al., GCN 13983; Yurkov et al., GCN 13984; Foley, GCN 13985; Xu et al., GCN 13986; Guziy et al., GCN 13987; Volnova et al., GCN 13988; Melandri et al., GCN 13989; Barthelmy et al., GCN 13990; Evans et al., GCN 13991; Schmidl et al., GCN 13992) was detected by the the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 10:06:00 UT (=T0).
The observed light curve shows a single peak followed by a long weak tail seen up to T0+74 s with a duration (T90) of about 73 seconds. The fluence in 100 - 1000 keV was 7.72 (+0.44/-7.11) x 10-6 erg/cm^2. The 1-s peak flux measured from T0+33 s was 0.74 (+0.54/-0.34) photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0+1 s to T0+74 s is well fitted by a single power-law with a photon index of 3.29 (+0.64/-0.50) (chi2/d.o.f = 4.7/11).
The light curves with 1-sec time resolution for this burst will be appeared at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html
GCN Report 403.1
GCN_Report 403.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_403_1.pdf by E.A. Helder at PSU titled: "Swift Observations of GRB 121123A"
GCN Circular #14088
FROM: Alessandro Monfardini at CNRS,Grenoble
A. Monfardini (I. N=C3=A9el, Grenoble), F.-X. D=C3=A9sert (IPAG, Grenoble), N. Ponthieu (IPAG, Grenoble), R. Adams (LPSC, Grenoble), M. Calvo (I. N=C3=A9el, Grenoble), J. Macias-Perez (LPSC, Grenoble), A. Catalano (LPSC, Grenoble), S. Leclercq (IRAM, Grenoble), P. Mauskopf (Arizona State U. & Cardiff U.), A. Benoit (I. N=C3=A9el, Grenoble), on behalf of the NIKA collaboration, report:=20
"During a technical run, we observed the position of GRB 121123A (E. A. Helder et al., GCN 13982) with the NIKA instrument being commissioned at the IRAM 30-m at Pico Veleta. Observations were accomplished between 15h and 16h UT on 24th November 2012 (mean time 29.5 hours after the burst), under poor observing conditions (tau225GHz ~ 0.35) and at relatively low elevation (35 deg). In roughly 40 minutes effective time on source, we do not detect the afterglow at the position given by D. Xu et al., GCN 13986. The following 3-sigma upper limits were derived:
U.L. 3 mJy at 150 GHz (99.7% C.L.)
U.L. 40 mJy at 240 GHz (99.7% C.L.), strongly limited by unstable weather conditions
NIKA is a multi-hundred-pixels dual-band continuum instrument operating simultaneously at central frequencies of 150 GHz (bandwidth 40 GHz) and 240 GHz (bandwidth 60 GHz). It is the first instrument based on the intrinsically multiplexable KID (Kinetic Inductance Detectors) technology installed permanently at a telescope. For more information about the instrument and the future project NIKA-2, see A. Monfardini et al., ApJS 194, Issue 2, id. 24 (2011).
We thank the IRAM Granada and Grenoble staff for their outstanding support before, during and after the NIKA run."
GCN Circular #14200
Yu. Krugly (Institute of Astronomy of Kharkiv National University), R.Inasaridze, O. Kvaratskhelia(Abastumani Astrophysical Observatory), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 121123A (Helder et al., GCN 13982) with AC-32 (0.7m Maksutov) telescope of Abastumani Observatory, starting on Nov. 23 (UT) 15:18. We took several unfiltered images of 180 s exposure. We clearly detected the afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983) in every single image. The photometry of the stacked images is based on USNO-B1.0 stars (R2):
```
Start,    T0+,        Filter,   Exp.,  OT
(UT)      (mid),days

15:18:28  0.2229      none      4x180  19.01 +/- 0.10
15:33:10  0.2337      none      4x180  18.96 +/- 0.09
15:48:15  0.2448      none      4x180  18.88 +/- 0.08
16:02:57  0.2551      none      4x180  19.17 +/- 0.11
16:02:57  0.2642      none      4x180  18.94 +/- 0.10
16:28:40  0.2729      none      4x180  19.06 +/- 0.11
```

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Jochen Greiner, last update: 13-Feb-2013 [Disclaimer]