Gamma-ray Burst 120212A

(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 12 Feb 12 09:11:43 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     514709,   Seg_Num: 0
GRB_RA:           43.105d {+02h 52m 25s} (J2000),
                  43.245d {+02h 52m 59s} (current),
                  42.526d {+02h 50m 06s} (1950)
GRB_DEC:         -18.025d {-18d 01' 29"} (J2000),
                 -17.976d {-17d 58' 32"} (current),
                 -18.229d {-18d 13' 45"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4622 [cnts]    Image_Peak=170 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   139     E_range: 15-50 keV
BKG_INTEN:       31344 [cnts]
BKG_TIME:        33064.11 SOD {09:11:04.11} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15969 TJD;    43 DOY;   12/02/12
GRB_TIME:        33082.74 SOD {09:11:22.74} UT
GRB_PHI:         -51.72 [deg]
GRB_THETA:        41.92 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     11.53 [sigma]
IMAGE_SIGNIF:    9.09 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +1  +0  +0  +0 -27  +0 
SUN_POSTN:       325.39d {+21h 41m 34s}  -13.83d {-13d 49' 56"}
SUN_DIST:         74.45 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.01d {+13h 16m 03s}  -12.24d {-12d 14' 26"}
MOON_DIST:       141.46 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       34.27,-32.85 [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 = 226.39,14.73 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(1.0<100sec) coincident with the FERMI_GBM event (trignum=350730685).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 12 Feb 12 09:11:53 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     350730685
GRB_RA:           40.833d {+02h 43m 20s} (J2000),
                  40.978d {+02h 43m 55s} (current),
                  40.236d {+02h 40m 57s} (1950)
GRB_DEC:         -13.217d {-13d 12' 59"} (J2000),
                 -13.166d {-13d 09' 55"} (current),
                 -13.428d {-13d 25' 40"} (1950)
GRB_ERROR:       21.80 [deg radius, statistical plus systematic]
GRB_INTEN:       78 [cnts/sec]
DATA_SIGNIF:     5.10 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        15969 TJD;    43 DOY;   12/02/12
GRB_TIME:        33083.50 SOD {09:11:23.50} UT
GRB_PHI:         298.00 [deg]
GRB_THETA:        55.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      2.42
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      65%  GRB
2nd_MOST_LIKELY:  19%  Generic SGR
DETECTORS:       0,0,0, 1,0,1, 1,0,0, 0,0,0, 0,0,
SUN_POSTN:       325.39d {+21h 41m 34s}  -13.83d {-13d 49' 56"}
SUN_DIST:         73.15 [deg]   Sun_angle= -5.0 [hr] (East of Sun)
MOON_POSTN:      199.01d {+13h 16m 03s}  -12.24d {-12d 14' 28"}
MOON_DIST:       146.53 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      190.50,-60.39 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       33.80,-27.58 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 200.33,-8.43 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(1.0<100sec) coincident with the SWIFT_BAT event (trignum=514709).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 12 Feb 12 09:13:35 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     350730685
GRB_RA:           26.630d {+01h 46m 31s} (J2000),
                  26.773d {+01h 47m 05s} (current),
                  26.042d {+01h 44m 10s} (1950)
GRB_DEC:         -22.740d {-22d 44' 23"} (J2000),
                 -22.680d {-22d 40' 46"} (current),
                 -22.989d {-22d 59' 21"} (1950)
GRB_ERROR:       8.19 [deg radius, statistical only]
DATA_SIGNIF:     7.90 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        15969 TJD;    43 DOY;   12/02/12
GRB_TIME:        33083.50 SOD {09:11:23.50} UT
GRB_PHI:         318.00 [deg]
GRB_THETA:        56.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       325.39d {+21h 41m 34s}  -13.83d {-13d 49' 54"}
SUN_DIST:         58.58 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:      199.03d {+13h 16m 07s}  -12.25d {-12d 14' 48"}
MOON_DIST:       144.26 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      196.58,-76.77 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       15.30,-31.27 [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(1.0<100sec) coincident with the SWIFT_BAT event (trignum=514709).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Feb 12 09:15:04 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     514709,   Seg_Num: 0
GRB_RA:           43.105d {+02h 52m 25s} (J2000),
                  43.245d {+02h 52m 59s} (current),
                  42.526d {+02h 50m 06s} (1950)
GRB_DEC:         -18.025d {-18d 01' 29"} (J2000),
                 -17.976d {-17d 58' 32"} (current),
                 -18.229d {-18d 13' 45"} (1950)
GRB_DATE:        15969 TJD;    43 DOY;   12/02/12
GRB_TIME:        33082.74 SOD {09:11:22.74} UT
TRIGGER_INDEX:   139
GRB_PHI:         -51.72 [deg]
GRB_THETA:        41.92 [deg]
DELTA_TIME:      58.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.53 [sigma]
IMAGE_SIGNIF:    9.09 [sigma]
LC_URL:          sw00514709000msb.lc
SUN_POSTN:       325.39d {+21h 41m 35s}  -13.83d {-13d 49' 53"}
SUN_DIST:         74.45 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.04d {+13h 16m 10s}  -12.25d {-12d 15' 05"}
MOON_DIST:       141.47 [deg]
MOON_ILLUM:      76 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       34.27,-32.85 [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 = 226.39,14.73 [deg].

GCN Circular #12930
E. Sonbas (NASA/GSFC/Adiyaman Univ.), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), C. Guidorzi (U Ferrara), A. Y. Lien (NASA/GSFC/ORAU), K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of the Swift Team:
At 09:11:22 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120212A (trigger=514709). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 43.105, -18.025 which is
```
   RA(J2000) = 02h 52m 25s
   Dec(J2000) = -18d 01' 29"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 8 sec. The peak count rate was ~1600 counts/sec (15-350 keV), at ~0 sec after the trigger.
Due to an observing constraint, Swift will not slew until T0+44.6 minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). 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 12 Feb 12 09:59:34 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     514709,   Seg_Num: 0
POINT_RA:         43.100d {+02h 52m 24s} (J2000)
POINT_DEC:       -18.024d {-18d 01' 25"} (J2000)
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35964.64 SOD {09:59:24.64} UT,   2881.9 [sec] since BAT Trigger Time
COUNTS:          1    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        0    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Feb 12 10:03:57 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     514709,   Seg_Num: 0
POINT_RA:         43.100d {+02h 52m 24s} (J2000)
POINT_DEC:       -18.023d {-18d 01' 24"} (J2000)
POINT_ROLL:      260.238d
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35968.11 SOD {09:59:28.11} UT,   2885.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.848
N_STARS:         73
X_OFFSET:        426 [pixels]
Y_OFFSET:        549 [pixels]
X_MAX:           1385 [pixels]
Y_MAX:           1508 [pixels]
DET_THRESH:      21
PHOTO_THRESH:    12
SL_URL:          sw00514709000msufc2885.fits
SUN_POSTN:       325.43d {+21h 41m 43s}  -13.82d {-13d 49' 12"}
SUN_DIST:         74.41 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.51d {+13h 18m 03s}  -12.41d {-12d 24' 30"}
MOON_DIST:       141.64 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.27,-32.84 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Feb 12 10:05:21 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     514709,   Seg_Num: 0
POINT_RA:         43.100d {+02h 52m 24s} (J2000)
POINT_DEC:       -18.023d {-18d 01' 24"} (J2000)
POINT_ROLL:      260.238d
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35968.11 SOD {09:59:28.11} UT,   2885.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.848
N_STARS:         73
X_OFFSET:        426 [pixels]
Y_OFFSET:        549 [pixels]
X_MAX:           1385 [pixels]
Y_MAX:           1508 [pixels]
DET_THRESH:      21
PHOTO_THRESH:    12
SL_URL:          sw00514709000msufc2885.fits
SUN_POSTN:       325.43d {+21h 41m 43s}  -13.82d {-13d 49' 11"}
SUN_DIST:         74.41 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.53d {+13h 18m 07s}  -12.41d {-12d 24' 46"}
MOON_DIST:       141.65 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.27,-32.84 [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 12 Feb 12 10:06:17 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     514709,   Seg_Num: 0
POINT_RA:         43.100d {+02h 52m 24s} (J2000)
POINT_DEC:       -18.023d {-18d 01' 24"} (J2000)
ROLL:            260.238d
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35968.11 SOD {09:59:28.11} UT,   2885.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     350733575
X_OFFSET:        745 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       905
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00514709000msuni2893.fits
SUN_POSTN:       325.43d {+21h 41m 43s}  -13.82d {-13d 49' 10"}
SUN_DIST:         74.41 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.54d {+13h 18m 09s}  -12.42d {-12d 24' 57"}
MOON_DIST:       141.65 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.27,-32.84 [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 12 Feb 12 10:06:42 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     514709,   Seg_Num: 0
POINT_RA:         43.100d {+02h 52m 24s} (J2000)
POINT_DEC:       -18.023d {-18d 01' 24"} (J2000)
ROLL:            260.238d
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35968.11 SOD {09:59:28.11} UT,   2885.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     350733575
X_OFFSET:        745 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       905
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00514709000msuni2893.fits
SUN_POSTN:       325.43d {+21h 41m 43s}  -13.82d {-13d 49' 10"}
SUN_DIST:         74.41 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.54d {+13h 18m 10s}  -12.42d {-12d 25' 02"}
MOON_DIST:       141.65 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      201.23,-60.72 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.27,-32.84 [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:     Sun 12 Feb 12 10:06:56 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     514709,   Seg_Num: 0
GRB_RA:           43.1017d {+02h 52m 24.40s} (J2000),
                  43.2419d {+02h 52m 58.06s} (current),
                  42.5231d {+02h 50m 05.54s} (1950)
GRB_DEC:         -18.0210d {-18d 01' 15.6"} (J2000),
                 -17.9718d {-17d 58' 18.5"} (current),
                 -18.2252d {-18d 13' 30.8"} (1950)
GRB_ERROR:       4.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15969 TJD;    43 DOY;   12/02/12
IMG_START_TIME:  35979.00 SOD {09:59:39.00} UT,   2896.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       325.43d {+21h 41m 43s}  -13.82d {-13d 49' 10"}
SUN_DIST:         74.41 [deg]   Sun_angle= -5.2 [hr] (East of Sun)
MOON_POSTN:      199.54d {+13h 18m 10s}  -12.42d {-12d 25' 05"}
MOON_DIST:       141.65 [deg]
MOON_ILLUM:      75 [%]
GAL_COORDS:      201.22,-60.72 [deg] galactic lon,lat of the burst
ECL_COORDS:       34.27,-32.84 [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 1.1% < P(seren) < 2.8%.

GCN Circular #12932
C. Guidorzi (U. Ferrara), C.G. Mundell, F. Virgili, I.A. Steele (LJMU), A. Melandri (INAF-OAB) report on behalf of a larger collaboration:
The 2-m Faulkes Telescope South automatically began observing GRB 120212A (Sonbas et al. GCN Circ. 12930) on February 2012, 09:25:18 UT corresponding to 14 minutes post burst with BVRi' filters. We found the following uncatalogued source,
```
R.A. = 02:52:24.06
Dec = -18:01:14.2   (J2000)
```
with an uncertainty of about 1" with a magnitude of R=16.3 at 22 minutes, calibrated against USNOB-1 stars. Presently, we cannot determine whether the source is fading.
GCN Circular #12933
E. A. Hoversten (PSU) and E. Sonbas (NASA/GSFC/Adiyaman Univ.) report on behalf of the Swift team:
UVOT took a finding chart exposure of 150 seconds with the White filter starting 2885 seconds after the BAT trigger. The source identified by Guidorzi et al. (GCN Circ. 12932) is detected in the rapidly available 2.7'x2.7' sub-image at
```
RA(J2000) =	02:52:24.06 = 43.10025
DEC(J2000) = -18:01:14.1 = -18.02057
```
with a 90%-confidence error radius of about 0.76 arc sec. This position is 5.21 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.31 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.03.
GCN Circular #12934
M. Perri (ASDC), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU) and G. Cusumano (INAF-IASF PA) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 120212A at 09:59:24.6 UT, 2881.9 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source located at RA, Dec 43.10208, -18.02125 which is equivalent to:
```
   RA(J2000)  = 02h 52m 24.50s
   Dec(J2000) = -18d 01' 16.5"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 16 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 (2.99 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 1.6 (+1.23/-1.13) x 10^21 cm^-2 (90% confidence).
GCN Circular #12935
K. S. Kawabata, H. Akitaya, M. Yamanaka, K. Takaki, T. Uehara, and M. Yoshida (Hiroshima Univ.) report on behalf of Kanata team:
We performed a series of optical imaging polarimetry for the optical afterglow of GRB 120212A (Guidorzi et al.; GCN 12932) using HOWPol attached to the 1.5-m Kanata telescope at Higashi-Hiroshima Observatory, Japan.
Our first exposure began at t=74 sec since Swift/BAT trigger (Sonbas et al.; GCN 12930), but the bright twilight sky shaded the afterglow until t=22 min. Our quick-look analysis indicates that Rc magnitude of the afterglow was 16.5 at t=23 min and faded to 17.6 at t=58 min. Further analysis is ongoing.
GCN Circular #12936
Kenshi Yanagisawa, Daisuke Kuroda, Yasuhiro Shimizu, Kiichi Okita (OAO/NAOJ), Michitoshi Yoshida (Hiroshima-U), Kouji Ohta(Kyoto-U), and Nobuyuki Kawai(Tokyo Tech.) report on behalf of the MITSuME collaboration:
We observed the field of GRB120212A (Sonbas et al., GCNC 12930, Perri et al., GCNC 12934) in Ks-band with a wide-field NIR camera at Okayama Astrophysical Observatory (Japan). The camera has an effective aperture of 0.91m.
Observations started from 10:01 UT on 12th February, 49.6 min after the BAT trigger, to 10:44 UT. The total exposure of 35 min was successfully obtained.
In our co-add image, we found a single point source at
```
  R.A.(J2000) = 02:52:24.08
  DEC (J2000) = -18:01:14.8
```
with an uncertainty of of about 2 arcsec. The position is consistent with the report by Guidorzi et al. (GCNC 12929)
We estimate the magnitude Ks = 15.13 +/- 0.19 (Vega). The calibration was made against 2MASS field stars.
```
T0+[min]    MID-UT     T-EXP[min]    Ks
------------------------------------------------------------
  +71.2     10:22:     35.0          15.13 +/- 0.19 (Vega)
------------------------------------------------------------
T0+ : Elapsed time after the burst [min]
T-EXP: Total Exposure time [min]
```
GCN Circular #12937
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 2484 s of XRT Photon Counting mode data and 7 UVOT images for GRB 120212A, 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 = 43.10025, -18.02079 which is equivalent to:
```
RA (J2000): 02h 52m 24.06s
Dec (J2000): -18d 01' 14.8"
```
with an uncertainty of 1.7 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #12938
Kenshi Yanagisawa, Daisuke Kuroda, Yasuhiro Shimizu, Kiichi Okita (OAO/NAOJ), Michitoshi Yoshida (Hiroshima-U), Kouji Ohta(Kyoto-U), and Nobuyuki Kawai(Tokyo Tech.) report on behalf of the MITSuME collaboration:
We made a typo on subject in GCNC 12936. The correct subject is $B!H(BGRB 120212A: MITSuME Okayama Ks-band observation$B!I(B. We apologize for the possible confusion.
GCN Circular #12939
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), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), E. Sonbas (NASA/GSFC/Adiyaman U), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120212A (trigger #514709) (Sonbas, et al., GCN Circ. 12930). The BAT ground-calculated position is RA, Dec = 43.086, -18.043 deg, which is
```
   RA(J2000)  =  02h 52m 20.6s 
   Dec(J2000) = -18d 02' 33.0" 
```
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 22%.
The mask-weighted light curve shows a single FRED pulse starting at ~T-0.7. peaking at ~T+1, and ending at ~T+6 sec. T90 (15-350 keV) is 5.52 +- 1.04 sec (estimated error including systematics).
The time-averaged spectrum from T-0.76 to T+6.09 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.05 +- 0.19. The fluence in the 15-150 keV band is 5.1 +- 0.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.02 sec in the 15-150 keV band is 2.1 +- 0.3 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/514709/BA/
GCN Circular #12940
N. P. M. Kuin (MSSL-UCL) and E. Sonbas (NASA/GSFC / Adiyaman_Univ.) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120212A 2885 s after the BAT trigger (Sonbas et al., GCN Circ. 12930). A source consistent with the enhanced XRT position (Osborne et al., GCN Circ. 12937) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
   RA  (J2000) =  02:52:24.05 =  43.10020 (deg.)
   Dec (J2000) = -18:01:14.2  = -18.02062 (deg.)
```
with an estimated uncertainty of 0.53 arc sec. (radius, 90% confidence).
The source is in the extended emission of a bright star (HD 17932) at a distance of 31", so the background was sampled at the same distance of that bright star as the GRB is.
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white             2885         3035          147         18.48 +/- 0.08
white             2885         5088          688         18.69 +/- 0.05
v                 2867         5379          286         18.12 +/- 0.12
b                 3249         4883          393         18.66 +/- 0.08
u                 3044         4678          393         18.47 +/- 0.10
w1                4274        11156          765        >21.0
m2                4069        10572         1082        >21.3
w2                3659         5294          393        >20.8
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12941
D. Xu (WIS), D. Malesani (DARK), G. Barisevicius (NOT), B. Nordstrom, J. Andersen (NBI), P. Jakobsson (U. Iceland) report on behalf of a larger collaboration:
We observed the field of GRB 120212A (Sonbas et al., GCN 12930) using the 2.5m Nordic Optical Telescope (NOT) equipped with the ALFSOC camera. We obtained 4x200s R-band images with a median time 19:52:24 UT on 2012-02-12, i.e., 10.7 hrs after the BAT trigger.
The optical afterglow of this burst (Guidorzi et al., GCN 12932; Hoversten et al., GCN 12933; Kawabata et al., GCN 12935; Kuin et al., GCN 12940) was clearly detected in our stacked image and had R ~ 20.1 mag calibrated with nearby stars in the USNO B1 catalog.
GCN Circular #12943
K.L. Page (U. Leicester) and E. Sonbas (NASA/GSFC/Adiyaman Univ.) report on behalf of the Swift-XRT team:
We have analysed 16 ks of XRT data for GRB 120212A (Sonbas et al. GCN Circ. 12930), from 2.9 ks to 44.6 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN. Circ 12937).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.25 (+/-0.06).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.11 (+0.16, -0.15). The best-fitting absorption column is 7.5 (+3.3, -3.0) x 10^20 cm^-2, in excess of the Galactic value of 3.0 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 3.4 x 10^-11 (4.3 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     7.5 (+3.3, -3.0) x 10^20 cm^-2
Galactic foreground: 3.0 x 10^20 cm^-2
Excess significance: 2.5 sigma
Photon index:	     2.11 (+0.16, -0.15)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00514709.
This circular is an official product of the Swift-XRT team.
GCN Circular #12947
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ), K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 120212A (Sonbas et al., GCNC 12230) with the optical three color (g', Rc and Ic) CCD camera attached to the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory.
The observation started on 2012-02-12 12:27:12 UT (~3.3 h after the burst). We detected the previously reported afterglow (Guidorzi et al.,GCNC 12932; Kawabata et al., GCNC 12935; Yanagisawa et al., GCNC 12936) in Rc and Ic bands.
Photometric results of the OT are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'    Rc  Rc_err   Ic  Ic_err
----------------------------------------------------------------------
0.14653    12:42:22    780.0    >20.2  18.7 0.2     18.4 0.3
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12949
X.-H. Zhao (YNAO), D. Xu (WIS), J.-R. Mao (KASI/YNAO), J.-M. Bai (YNAO) report on behalf of a larger collaboration:
We observed the field of GRB 120212A (Sonbas et al., GCN 12930) with 2.4m Gao-Mei-Gu (GMG) telescope. Observations started at 12:11:45 UT on 2012-02-12 (i.e., ~3 hrs after the burst) and 3x600s R-band images were obtained. The optical afterglow of this burst (Guidorzi et al., GCN 12932; Hoversten et al., GCN 12933; Kawabata et al., GCN 12935; Kuin et al., GCN 12940; Xu et al., GCN 12941; Kuroda et al., GCN 12947) was detected. The results are as follows:
```
Comparison star: USNO-B Catalog 0720-0030593, R=18.31
UT(start time)    Mag.    Err.    Exposure time (second)
12:11:45.283      18.77   0.05      600
12:23:51.293      18.64   0.05      600
12:35:30.413      18.96   0.05      600
```
We thank the GMG staff, especially Ju-Jia Zhang, Jian-Quan He, and De-Qing Wang for performing these observations.
GCN Circular #12950
Arne Rau (MPE) reports on behalf of the Fermi GBM Team:
"At 09:11:23.50 UT on 12 February 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120212A (trigger 350730685 / 120212383) which was also detected by the Swift/BAT (Sonbas et al. 2012, GCN 12930). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 53 degrees.
The GBM light curve shows/consists of a single peak with a duration (T90) of about 9.2 s (50-300 keV). The time-averaged spectrum from T0-3.1 s to T0+6.1 s is best fit by a simple power law function with index -1.83 =B1 0.06
The event fluence (10-1000 keV) in this time interval is (1.407 =B1 0.120)E-07 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+0.64 s in the 10-1000 keV band is 3.3 =B1 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."

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Jochen Greiner, last update: 13-Feb-2012 [Disclaimer]