Gamma-ray Burst 121202A

(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:     Sun 02 Dec 12 04:20:25 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     540255,   Seg_Num: 0
GRB_RA:          256.815d {+17h 07m 16s} (J2000),
                 256.949d {+17h 07m 48s} (current),
                 256.295d {+17h 05m 11s} (1950)
GRB_DEC:         +23.952d {+23d 57' 07"} (J2000),
                 +23.936d {+23d 56' 08"} (current),
                 +24.017d {+24d 01' 00"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3717 [cnts]    Image_Peak=179 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       22853 [cnts]
BKG_TIME:        15590.06 SOD {04:19:50.06} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16263 TJD;   337 DOY;   12/12/02
GRB_TIME:        15605.03 SOD {04:20:05.03} UT
GRB_PHI:         -26.35 [deg]
GRB_THETA:        33.44 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     13.78 [sigma]
IMAGE_SIGNIF:    7.49 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  -2  +0  +0 -68  +0 
SUN_POSTN:       248.78d {+16h 35m 07s}  -22.00d {-22d 00' 14"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.14d {+07h 20m 33s}  +17.87d {+17d 52' 22"}
MOON_DIST:       127.12 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.84 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      252.34, 46.59 [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 = 226.05,-13.04 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(4.0<100sec) coincident with the FERMI_GBM event (trignum=376114812).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 02 Dec 12 04:20:38 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     376114812
GRB_RA:          257.850d {+17h 11m 24s} (J2000),
                 257.974d {+17h 11m 54s} (current),
                 257.369d {+17h 09m 29s} (1950)
GRB_DEC:         +30.383d {+30d 22' 60"} (J2000),
                 +30.368d {+30d 22' 06"} (current),
                 +30.443d {+30d 26' 35"} (1950)
GRB_ERROR:       34.88 [deg radius, statistical plus systematic]
GRB_INTEN:       50 [cnts/sec]
DATA_SIGNIF:     4.60 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16263 TJD;   337 DOY;   12/12/02
GRB_TIME:        15609.17 SOD {04:20:09.17} UT
GRB_PHI:          43.00 [deg]
GRB_THETA:        70.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.58
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      53%  GRB
2nd_MOST_LIKELY:  33%  Solar Flare
DETECTORS:       0,1,1, 0,0,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       248.78d {+16h 35m 07s}  -22.00d {-22d 00' 14"}
SUN_DIST:         53.11 [deg]   Sun_angle= -0.6 [hr] (East of Sun)
MOON_POSTN:      110.14d {+07h 20m 34s}  +17.87d {+17d 52' 21"}
MOON_DIST:       122.68 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       52.89, 33.73 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      252.41, 53.08 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 104.62,15.60 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(4.0<100sec) coincident with the SWIFT_BAT event (trignum=540255).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 02 Dec 12 04:20:56 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     376114812
GRB_RA:          249.000d {+16h 36m 00s} (J2000),
                 249.105d {+16h 36m 25s} (current),
                 248.593d {+16h 34m 22s} (1950)
GRB_DEC:         +41.900d {+41d 53' 60"} (J2000),
                 +41.874d {+41d 52' 27"} (current),
                 +42.001d {+42d 00' 03"} (1950)
GRB_ERROR:       11.08 [deg radius, statistical only]
DATA_SIGNIF:     5.90 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16263 TJD;   337 DOY;   12/12/02
GRB_TIME:        15609.17 SOD {04:20:09.17} UT
GRB_PHI:          55.00 [deg]
GRB_THETA:        77.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       248.78d {+16h 35m 07s}  -22.00d {-22d 00' 14"}
SUN_DIST:         63.88 [deg]   Sun_angle= -0.0 [hr] (East of Sun)
MOON_POSTN:      110.14d {+07h 20m 34s}  +17.87d {+17d 52' 19"}
MOON_DIST:       109.25 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       66.18, 42.35 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      234.35, 62.76 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(4.0<100sec) coincident with the SWIFT_BAT event (trignum=540255).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 02 Dec 12 04:23:54 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     540255,   Seg_Num: 0
GRB_RA:          256.815d {+17h 07m 16s} (J2000),
                 256.949d {+17h 07m 48s} (current),
                 256.295d {+17h 05m 11s} (1950)
GRB_DEC:         +23.952d {+23d 57' 07"} (J2000),
                 +23.936d {+23d 56' 08"} (current),
                 +24.017d {+24d 01' 00"} (1950)
GRB_DATE:        16263 TJD;   337 DOY;   12/12/02
GRB_TIME:        15605.03 SOD {04:20:05.03} UT
TRIGGER_INDEX:   146
GRB_PHI:         -26.35 [deg]
GRB_THETA:        33.44 [deg]
DELTA_TIME:      -56.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     13.78 [sigma]
IMAGE_SIGNIF:    7.49 [sigma]
LC_URL:          sw00540255000msb.lc
SUN_POSTN:       248.78d {+16h 35m 08s}  -22.00d {-22d 00' 15"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.17d {+07h 20m 40s}  +17.87d {+17d 52' 02"}
MOON_DIST:       127.11 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.84 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      252.34, 46.59 [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 = 226.05,-13.04 [deg].

GCN Circular #14032
S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 04:20:05 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 121202A (trigger=540255). Swift did not slew because of the Earth limb observing constraint. The BAT on-board calculated location is RA, Dec 256.815, +23.952, which is
```
   RA(J2000)  =  17h 07m 16s
   Dec(J2000) = +23d 57' 07"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows muliple peaks with a total duration of about 40 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~13 sec after the trigger.
Due to an observing constraint, Swift will not slew until T0+44.1 minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is S. R. Oates (sro AT mssl.ucl.ac.uk). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 02 Dec 12 05:07:17 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     540255,   Seg_Num: 0
POINT_RA:        256.791d {+17h 07m 10s} (J2000)
POINT_DEC:       +23.958d {+23d 57' 28"} (J2000)
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18429.73 SOD {05:07:09.73} UT,   2824.7 [sec] since BAT Trigger Time
COUNTS:          4    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN Circular #14033
Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR), Boer M. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report:
We imaged the field of GRB 121202 detected by SWIFT (trigger 540255) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
The observations started 34.0s after the GRB trigger (15.8s after the notice). However, the elevation of the field increased from 1 degrees above horizon so it was possible to detect stars on images only 275s after the trigger.
The first image does not show any optical counterpart: t0+275s to t0+305s : R > 14.9
We co-added series of exposures:
```
t0+275s to t0+1419s : R > 16.2
t0+1633s to t0+2578s : R > 16.9
```
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon= 45.1864 lat=+32.8357 and the galactic extinction in R band is about 0.1 magnitude estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 02 Dec 12 05:11:14 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     540255,   Seg_Num: 0
POINT_RA:        256.791d {+17h 07m 10s} (J2000)
POINT_DEC:       +23.958d {+23d 57' 28"} (J2000)
POINT_ROLL:      190.283d
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18433.56 SOD {05:07:13.56} UT,   2828.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.371
N_STARS:         61
X_OFFSET:        403 [pixels]
Y_OFFSET:        397 [pixels]
X_MAX:           1362 [pixels]
Y_MAX:           1356 [pixels]
DET_THRESH:      20
PHOTO_THRESH:    11
SL_URL:          sw00540255000msufc2828.fits
SUN_POSTN:       248.82d {+16h 35m 16s}  -22.01d {-22d 00' 33"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.57d {+07h 22m 18s}  +17.79d {+17d 47' 26"}
MOON_DIST:       126.90 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.86 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      252.31, 46.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 02 Dec 12 05:11:17 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     540255,   Seg_Num: 0
GRB_RA:          256.7968d {+17h 07m 11.23s} (J2000),
                 256.9312d {+17h 07m 43.49s} (current),
                 256.2767d {+17h 05m 06.41s} (1950)
GRB_DEC:         +23.9488d {+23d 56' 55.6"} (J2000),
                 +23.9325d {+23d 55' 56.8"} (current),
                 +24.0136d {+24d 00' 49.0"} (1950)
GRB_ERROR:       4.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18453.00 SOD {05:07:33.00} UT,   2848.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       248.82d {+16h 35m 16s}  -22.01d {-22d 00' 33"}
SUN_DIST:         46.61 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.57d {+07h 22m 18s}  +17.79d {+17d 47' 25"}
MOON_DIST:       126.91 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.18, 32.85 [deg] galactic lon,lat of the burst
ECL_COORDS:      252.32, 46.58 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 02 Dec 12 05:11:38 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     540255,   Seg_Num: 0
POINT_RA:        256.791d {+17h 07m 10s} (J2000)
POINT_DEC:       +23.958d {+23d 57' 28"} (J2000)
POINT_ROLL:      190.283d
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18433.56 SOD {05:07:13.56} UT,   2828.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.371
N_STARS:         61
X_OFFSET:        403 [pixels]
Y_OFFSET:        397 [pixels]
X_MAX:           1362 [pixels]
Y_MAX:           1356 [pixels]
DET_THRESH:      20
PHOTO_THRESH:    11
SL_URL:          sw00540255000msufc2828.fits
SUN_POSTN:       248.82d {+16h 35m 16s}  -22.01d {-22d 00' 33"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.58d {+07h 22m 19s}  +17.79d {+17d 47' 23"}
MOON_DIST:       126.90 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.86 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      252.31, 46.59 [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:     Sun 02 Dec 12 05:13:24 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     540255,   Seg_Num: 0
POINT_RA:        256.791d {+17h 07m 10s} (J2000)
POINT_DEC:       +23.958d {+23d 57' 28"} (J2000)
ROLL:            190.283d
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18433.56 SOD {05:07:13.56} UT,   2828.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     376117643
X_OFFSET:        722 [pixels]
Y_OFFSET:        716 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       876
BINNING_INDEX:   1
IM_URL:          sw00540255000msuni2838.fits
SUN_POSTN:       248.82d {+16h 35m 17s}  -22.01d {-22d 00' 33"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.59d {+07h 22m 22s}  +17.79d {+17d 47' 13"}
MOON_DIST:       126.89 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.86 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      252.31, 46.59 [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:     Sun 02 Dec 12 05:13:39 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     540255,   Seg_Num: 0
POINT_RA:        256.791d {+17h 07m 10s} (J2000)
POINT_DEC:       +23.958d {+23d 57' 28"} (J2000)
ROLL:            190.283d
IMG_START_DATE:  16263 TJD;   337 DOY;   12/12/02
IMG_START_TIME:  18433.56 SOD {05:07:13.56} UT,   2828.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     376117643
X_OFFSET:        722 [pixels]
Y_OFFSET:        716 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       882
Y_GRB_POS:       876
BINNING_INDEX:   1
IM_URL:          sw00540255000msuni2838.fits
SUN_POSTN:       248.82d {+16h 35m 17s}  -22.01d {-22d 00' 33"}
SUN_DIST:         46.62 [deg]   Sun_angle= -0.5 [hr] (East of Sun)
MOON_POSTN:      110.60d {+07h 22m 23s}  +17.79d {+17d 47' 12"}
MOON_DIST:       126.89 [deg]
MOON_ILLUM:      89 [%]
GAL_COORDS:       45.19, 32.86 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      252.31, 46.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #14034
M. H. Siegel (PSU) and S. R. Oates (UCL-MSSL) report on behalf of the Swift/UVOT team:
Swift/UVOT began settled observations of the field of GRB 121202A 2828 s after the BAT trigger (Oates et al., GCN Circ 14032). UVOT took a finding chart exposure of 150 seconds with the White filter. 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 0.05.
GCN Circular #14036
P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU), S. Campana (INAF-OAB) and G. Cusumano (INAF-IASF PA) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 121202A at 05:07:09.7 UT, 2824.7 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 256.79704, 23.94886 which is equivalent to:
```
   RA(J2000)  = 17h 07m 11.29s
   Dec(J2000) = +23d 56' 55.9"
```
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 60 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 http://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (3.91 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 3.9 (+2.19/-1.90) x 10^21 cm^-2 (90% confidence).
GCN Circular #14037
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 121202A (trigger #540255) (Oates, et al., GCN Circ. 14032). The BAT ground-calculated position is RA, Dec = 256.790, 23.942 deg, which is
```
   RA(J2000)  =  17h 07m 09.7s 
   Dec(J2000) = +23d 56' 32.5" 
```
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 70%.
The mask-weighted light curve shows a cluster of overlapping peaks starting at ~T-10 sec and ending at ~T+25 sec. T90 (15-350 keV) is 20.1 +- 1.9 sec (estimated error including systematics).
The time-averaged spectrum from T-2.18 to T+20.84 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.59 +- 0.11. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.02 sec in the 15-150 keV band is 1.2 +- 0.2 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/540255/BA/
GCN Circular #14038
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 4781 s of XRT Photon Counting mode data and 9 UVOT images for GRB 121202A, 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 = 256.79689, +23.94818 which is equivalent to:
```
RA (J2000): 17h 07m 11.25s
Dec (J2000): +23d 56' 53.4"
```
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 #14039
D. Tierney (UCD) reports on behalf of the Fermi GBM Team:
"At 04:20:09.17 UT on 02 December 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 121202A (trigger 376114812 / 121202181) which was also detected by the Swift/BAT (Oates et al. 2012, GCN 14032) The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 62 degrees.
The GBM light curve consists of a single weak pulse with a duration (T90) of 17.7 +/- 1.7 s (50-300 keV). The time-averaged spectrum from T0-4.1 s to T0+17.4 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.14 (+0.19/-0.17) and the cutoff energy, parameterized as Epeak, is 135.4 (+23.6/-23.0) keV.
The event fluence (10-1000 keV) in this time interval is (2.0 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-5.1 s in the 10-1000 keV band is 2.0 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #14040
K.L. Page (U. Leicester) and S. R. Oates (UCL-MSSL) report on behalf of the Swift-XRT team:
We have analysed 12 ks of XRT data for GRB 121202A (Oates et al. GCN Circ. 14032), from 2.8 ks to 31.9 ks after the BAT trigger. The data comprise 16 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 14038).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.66 (+/-0.08).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.08 (+/-0.15). The best-fitting absorption column is 1.7 (+/-0.4) x 10^21 cm^-2, in excess of the Galactic value of 3.9 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (5.3 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.7 (+/-0.4) x 10^21 cm^-2
Galactic foreground: 3.9 x 10^20 cm^-2
Excess significance: 5.5 sigma
Photon index:	     2.08 (+/-0.15)
```
If the light curve continues to decay with a power-law decay index of 1.66, the count rate at T+24 hours will be 2.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.5 x 10^-14 (1.1 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/00540255.
This circular is an official product of the Swift-XRT team.
GCN Circular #14041
S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 121202A 2828 s after the BAT trigger (Oates et al., GCN Circ. 14032). No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 14038) 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          2828         2978          147         >20.3
white             2828         5033          541         >21.0
v                 3808        16147         1205         >20.2
b                 3192        22680         1059         >20.9
u                 2987        28451         2637         >21.2
w1                4218        27811         2853         >21.4
m2                4012        26905         2713         >21.5
w2                3603        31934         1549         >21.2
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998).
GCN Report 407.1
GCN_Report 407.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_407_1.pdf by S.R. Oates at UCL-MSSL titled: "Swift Observations of GRB 121202A"

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Jochen Greiner, last update: 04-Jan-2013 [Disclaimer]