Gamma-ray Burst 100111A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:13:05 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     382399,   Seg_Num: 0
GRB_RA:          247.038d {+16h 28m 09s} (J2000),
                 247.152d {+16h 28m 37s} (current),
                 246.469d {+16h 25m 53s} (1950)
GRB_DEC:         +15.557d {+15d 33' 25"} (J2000),
                 +15.535d {+15d 32' 07"} (current),
                 +15.667d {+15d 40' 00"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       2827 [cnts]    Image_Peak=258 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   124     E_range: 25-100 keV
BKG_INTEN:       31120 [cnts]
BKG_TIME:        15154.57 SOD {04:12:34.57} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15207 TJD;    11 DOY;   10/01/11
GRB_TIME:        15169.03 SOD {04:12:49.03} UT
GRB_PHI:         -159.38 [deg]
GRB_THETA:        16.07 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     18.11 [sigma]
IMAGE_SIGNIF:    12.08 [sigma]
MERIT_PARAMS:     +1  +0  +0  -1  +2  +1  +0  +0 -52  +0 
SUN_POSTN:       292.51d {+19h 30m 03s}  -21.83d {-21d 49' 29"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.45d {+16h 09m 48s}  -24.93d {-24d 55' 58"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      242.01, 36.79 [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 = 91.93,16.87 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:13:27 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     284875971
GRB_RA:          239.730d {+15h 58m 55s} (J2000),
                 239.848d {+15h 59m 24s} (current),
                 239.142d {+15h 56m 34s} (1950)
GRB_DEC:         +12.280d {+12d 16' 48"} (J2000),
                 +12.252d {+12d 15' 07"} (current),
                 +12.422d {+12d 25' 18"} (1950)
GRB_ERROR:       7.54 [deg radius, statistical only]
DATA_SIGNIF:     7.40 [sigma]
DATA_INTERVAL:   2.048 [sec]
GRB_DATE:        15207 TJD;    11 DOY;   10/01/11
GRB_TIME:        15169.70 SOD {04:12:49.70} UT
GRB_PHI:         266.00 [deg]
GRB_THETA:        40.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   413 (Gnd S/W Version number)
SUN_POSTN:       292.51d {+19h 30m 03s}  -21.83d {-21d 49' 29"}
SUN_DIST:         61.88 [deg]   Sun_angle= 3.5 [hr] (West of Sun)
MOON_POSTN:      242.45d {+16h 09m 48s}  -24.93d {-24d 56' 00"}
MOON_DIST:        37.27 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       23.75, 43.75 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      234.47, 32.06 [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:     Mon 11 Jan 10 04:13:12 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     284875971
GRB_RA:          239.733d {+15h 58m 56s} (J2000),
                 239.851d {+15h 59m 24s} (current),
                 239.145d {+15h 56m 35s} (1950)
GRB_DEC:         +12.267d {+12d 15' 60"} (J2000),
                 +12.239d {+12d 14' 19"} (current),
                 +12.408d {+12d 24' 29"} (1950)
GRB_ERROR:       12.30 [deg radius, statistical plus systematic]
GRB_INTEN:       95 [cnts/sec]
DATA_SIGNIF:     5.80 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        15207 TJD;    11 DOY;   10/01/11
GRB_TIME:        15169.70 SOD {04:12:49.70} UT
GRB_PHI:         265.98 [deg]
GRB_THETA:        40.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      1.59
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      69%  GRB
2nd_MOST_LIKELY:  11%  Generic SGR
DETECTORS:       0,0,0, 1,0,0, 1,0,0, 0,0,0, 0,0,
SUN_POSTN:       292.51d {+19h 30m 03s}  -21.83d {-21d 49' 29"}
SUN_DIST:         61.87 [deg]   Sun_angle= 3.5 [hr] (West of Sun)
MOON_POSTN:      242.45d {+16h 09m 48s}  -24.93d {-24d 55' 58"}
MOON_DIST:        37.26 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       23.73, 43.74 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      234.47, 32.05 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 97.83,-23.83 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:14:04 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 26"} (J2000)
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15232.08 SOD {04:13:52.08} UT,   63.0 [sec] since BAT Trigger Time
COUNTS:          58    Min_needed= 20
STD_DEV:         35.64   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      3
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        Standard deviation too large.

GCN NOTICE

TITLE:        GCN/SIMBAD_NED NOTICE
NOTICE_DATE:  Mon Jan 11 04:14:33 UTC 2010
NOTICE_TYPE:  Swift-BAT Position search
TRIGGER_NUM:  382399
RA:           247.0381 (J2000)
DEC:          15.5569 (J2000)
 
SIMBAD search for BAT_RA,Dec=247.0381,15.5569,radius=10.0arcmin
 
Num   RA         Dec                    Name                        Type  Num_Pub  Distance

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:16:36 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     382399,   Seg_Num: 0
GRB_RA:          247.038d {+16h 28m 09s} (J2000),
                 247.152d {+16h 28m 37s} (current),
                 246.469d {+16h 25m 53s} (1950)
GRB_DEC:         +15.557d {+15d 33' 25"} (J2000),
                 +15.535d {+15d 32' 07"} (current),
                 +15.667d {+15d 40' 00"} (1950)
GRB_DATE:        15207 TJD;    11 DOY;   10/01/11
GRB_TIME:        15169.03 SOD {04:12:49.03} UT
TRIGGER_INDEX:   124
GRB_PHI:         -159.38 [deg]
GRB_THETA:        16.07 [deg]
DELTA_TIME:      -5.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     18.11 [sigma]
IMAGE_SIGNIF:    12.08 [sigma]
LC_URL:          sw00382399000msb.lc
SUN_POSTN:       292.51d {+19h 30m 03s}  -21.82d {-21d 49' 28"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.48d {+16h 09m 56s}  -24.94d {-24d 56' 11"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      242.01, 36.79 [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 = 91.93,16.87 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:17:25 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 25"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.29 SOD {04:13:56.29} UT,   67.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.311
N_STARS:         77
X_OFFSET:        478 [pixels]
Y_OFFSET:        531 [pixels]
X_MAX:           1437 [pixels]
Y_MAX:           1490 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00382399000msufc0067.fits
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 28"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.49d {+16h 09m 57s}  -24.94d {-24d 56' 14"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:17:58 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 25"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.29 SOD {04:13:56.29} UT,   67.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.311
N_STARS:         77
X_OFFSET:        478 [pixels]
Y_OFFSET:        531 [pixels]
X_MAX:           1437 [pixels]
Y_MAX:           1490 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00382399000msufc0067.fits
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 27"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.49d {+16h 09m 59s}  -24.94d {-24d 56' 16"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:18:12 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     382399,   Seg_Num: 0
GRB_RA:          247.0474d {+16h 28m 11.37s} (J2000),
                 247.1616d {+16h 28m 38.77s} (current),
                 246.4783d {+16h 25m 54.80s} (1950)
GRB_DEC:         +15.5509d {+15d 33' 03.2"} (J2000),
                 +15.5292d {+15d 31' 45.0"} (current),
                 +15.6607d {+15d 39' 38.6"} (1950)
GRB_ERROR:       3.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15246.00 SOD {04:14:06.00} UT,   77.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 27"}
SUN_DIST:         58.06 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.50d {+16h 09m 59s}  -24.94d {-24d 56' 17"}
MOON_DIST:        40.72 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.60 [deg] galactic lon,lat of the burst
ECL_COORDS:      242.02, 36.79 [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:     Mon 11 Jan 10 04:18:38 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 25"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.29 SOD {04:13:56.29} UT,   67.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     284876041
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0073.fits
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 27"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.50d {+16h 10m 00s}  -24.94d {-24d 56' 18"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:18:57 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 25"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.29 SOD {04:13:56.29} UT,   67.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     284876041
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0073.fits
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 27"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.50d {+16h 10m 01s}  -24.94d {-24d 56' 19"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:17:25 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.038d {+16h 28m 09s} (J2000)
POINT_DEC:       +15.557d {+15d 33' 25"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.29 SOD {04:13:56.29} UT,   67.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.311
N_STARS:         77
X_OFFSET:        478 [pixels]
Y_OFFSET:        531 [pixels]
X_MAX:           1437 [pixels]
Y_MAX:           1490 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00382399000msufc0067.fits
SUN_POSTN:       292.52d {+19h 30m 04s}  -21.82d {-21d 49' 28"}
SUN_DIST:         58.07 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.49d {+16h 09m 57s}  -24.94d {-24d 56' 14"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.61 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:23:59 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     382399,   Seg_Num: 0
GRB_RA:          247.0483d {+16h 28m 11.59s} (J2000),
                 247.1625d {+16h 28m 38.99s} (current),
                 246.4792d {+16h 25m 55.01s} (1950)
GRB_DEC:         +15.5505d {+15d 33' 01.7"} (J2000),
                 +15.5288d {+15d 31' 43.6"} (current),
                 +15.6603d {+15d 39' 37.2"} (1950)
GRB_ERROR:       0.6 [arcsec radius, statistical only]
GRB_MAG:         17.57 +/- 0.14 [mag]
FILTER:          10, White
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15236.00 SOD {04:13:56.00} UT,   67.0 [sec] since BAT Trigger Time
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 25"}
SUN_DIST:         58.06 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.55d {+16h 10m 12s}  -24.94d {-24d 56' 38"}
MOON_DIST:        40.72 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.60 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      242.02, 36.79 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN Circular #10317
L. Vetere (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), C. Gronwall (PSU), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU), C. B. Markwardt (CRESST/GSFC/UMD), C. Pagani (PSU), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 04:12:49 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 100111A (trigger=382399). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 247.038, +15.557 which is
```
   RA(J2000) = 16h 28m 09s
   Dec(J2000) = +15d 33' 25"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a small precursor peak followed by a main FRED peak for a total duration of about 30 sec. The peak count rate was ~3800 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 04:13:52.1 UT, 63.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 247.04766, 15.55090 which is equivalent to:
```
   RA(J2000)  = 16h 28m 11.44s
   Dec(J2000) = +15d 33' 03.2"
```
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 40 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. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (4.09e+20 cm^-2, Kalberla et al. 2005), with an excess column of 2 (+2.19/-1.28) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 67 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =  16:28:11.60 = 247.04833
  DEC(J2000) = +15:33:02.3  = 15.55064
```
with a 90%-confidence error radius of about 0.62 arc sec. This position is 3.4 arc sec. from the center of the XRT error circle. The estimated magnitude is 17.58 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05.
Burst Advocate for this burst is L. Vetere (vetere AT astro.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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:25:58 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15448.44 SOD {04:17:28.44} UT,   279.4 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.259
N_STARS:         90
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00382399000msufc0279.fits
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.57d {+16h 10m 17s}  -24.95d {-24d 56' 45"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:26:26 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15448.44 SOD {04:17:28.44} UT,   279.4 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.259
N_STARS:         90
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00382399000msufc0279.fits
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.57d {+16h 10m 18s}  -24.95d {-24d 56' 47"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:27:06 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     382399,   Seg_Num: 0
GRB_RA:          247.0485d {+16h 28m 11.63s} (J2000),
                 247.1627d {+16h 28m 39.04s} (current),
                 246.4794d {+16h 25m 55.06s} (1950)
GRB_DEC:         +15.5505d {+15d 33' 01.7"} (J2000),
                 +15.5288d {+15d 31' 43.6"} (current),
                 +15.6603d {+15d 39' 37.2"} (1950)
GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15246.00 SOD {04:14:06.00} UT,   77.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.06 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.58d {+16h 10m 19s}  -24.95d {-24d 56' 49"}
MOON_DIST:        40.72 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.60 [deg] galactic lon,lat of the burst
ECL_COORDS:      242.02, 36.79 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:27:15 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15448.44 SOD {04:17:28.44} UT,   279.4 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     284876253
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0285.fits
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.58d {+16h 10m 20s}  -24.95d {-24d 56' 50"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:27:42 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15448.44 SOD {04:17:28.44} UT,   279.4 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     284876253
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0285.fits
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.59d {+16h 10m 21s}  -24.95d {-24d 56' 51"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:25:58 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  15448.44 SOD {04:17:28.44} UT,   279.4 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.259
N_STARS:         90
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00382399000msufc0279.fits
SUN_POSTN:       292.52d {+19h 30m 05s}  -21.82d {-21d 49' 24"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.57d {+16h 10m 17s}  -24.95d {-24d 56' 45"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:34:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  16026.58 SOD {04:27:06.58} UT,   857.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.426
N_STARS:         104
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    14
SL_URL:          sw00382399000msufc0857.fits
SUN_POSTN:       292.53d {+19h 30m 07s}  -21.82d {-21d 49' 21"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.65d {+16h 10m 36s}  -24.95d {-24d 57' 15"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:34:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  16026.58 SOD {04:27:06.58} UT,   857.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.426
N_STARS:         104
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    14
SL_URL:          sw00382399000msufc0857.fits
SUN_POSTN:       292.53d {+19h 30m 07s}  -21.82d {-21d 49' 21"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.65d {+16h 10m 36s}  -24.95d {-24d 57' 15"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:34:54 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
POINT_ROLL:      128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  16026.58 SOD {04:27:06.58} UT,   857.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.426
N_STARS:         104
X_OFFSET:        238 [pixels]
Y_OFFSET:        291 [pixels]
X_MAX:           1677 [pixels]
Y_MAX:           1730 [pixels]
DET_THRESH:      24
PHOTO_THRESH:    14
SL_URL:          sw00382399000msufc0857.fits
SUN_POSTN:       292.53d {+19h 30m 07s}  -21.82d {-21d 49' 21"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.65d {+16h 10m 37s}  -24.96d {-24d 57' 17"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:36:50 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  16026.58 SOD {04:27:06.58} UT,   857.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     284876832
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0863.fits
SUN_POSTN:       292.53d {+19h 30m 07s}  -21.82d {-21d 49' 20"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.67d {+16h 10m 41s}  -24.96d {-24d 57' 24"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 11 Jan 10 04:37:17 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     382399,   Seg_Num: 0
POINT_RA:        247.035d {+16h 28m 08s} (J2000)
POINT_DEC:       +15.556d {+15d 33' 21"} (J2000)
ROLL:            128.831d
IMG_START_DATE:  15207 TJD;    11 DOY;   10/01/11
IMG_START_TIME:  16026.58 SOD {04:27:06.58} UT,   857.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     284876832
X_OFFSET:        797 [pixels]
Y_OFFSET:        850 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       957
Y_GRB_POS:       1010
BINNING_INDEX:   1
IM_URL:          sw00382399000msuni0863.fits
SUN_POSTN:       292.53d {+19h 30m 07s}  -21.82d {-21d 49' 20"}
SUN_DIST:         58.08 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      242.68d {+16h 10m 42s}  -24.96d {-24d 57' 26"}
MOON_DIST:        40.73 [deg]
MOON_ILLUM:      15 [%]
GAL_COORDS:       31.58, 38.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      242.01, 36.79 [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 #10318
D. Xu (WIS, DARK/NBI), N. Tanvir (U. Leicester), J.P.U. Fynbo (DARK/NBI), P. Jakobsson (Univ. of Iceland), T. Liimets (NOT) report on behalf of a larger collaboration:
We observed the field of GRB100111A (Vetere et al., GCN 10317) with the Nordic Optical Telescope equipped with ALFOSC. A 30 s R-band frame was obtained, starting at 05:25:45 UT on Jan 11, 73 min after the burst trigger. The afterglow is clearly detected in the frame with R=19.46+/-0.05 mag calibrated with the nearby #1055-0262005 star in the USNO B1 catalog.
GCN Circular #10319
S. McBreen (UCD/MPE) reports on behalf of the Fermi GBM Team:
"At 04:12:49.70 UT on 11 January 2010, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 100111A (trigger 284875971 / 100111176) which was also detected by the Swift-BAT (Vetere et al. 2010, GCN 10317). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 32 degrees.
The GBM light curve consists of one main pulse with a duration of about 12 s (8-1000 keV). The time-averaged spectrum from T0-2.7 s to T0+5.5 s is adequately fit by a simple power law function with index -1.66 (+0.05/-0.06) (CSTAT 452 for 363 d.o.f.).
The event fluence (8-1000 keV) in this time interval is (1.5 +/- 0.1 )E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.003 s in the 8-1000 keV band is 3.5 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #10320
L. Vetere (PSU) reports on behalf of the Swift-XRT team:
We have analysed 774 s of XRT data for GRB 100111A (Vetere et al. GCN Circ. 10317), from 77 s to 852 s after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The light curve can be modelled with a power-law decay with a decay index of alpha=0.58 +/- 0.16.
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.10 (+0.29, -0.26). The best-fitting absorption column is 1.7 (+0.8, -0.7) x 10^21 cm^-2, in excess of the Galactic value of 4.1 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 3.8 x 10^-11 (5.7 x 10^-11) erg cm^-2 count^-1.
If the light curve continues to decay with a power-law decay index of 0.58, the count rate at T+24 hours will be 0.023 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.7 x 10^-13 (1.3 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/00382399.
This circular is an official product of the Swift-XRT team.
GCN Circular #10321
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 5361 s of XRT Photon Counting mode data and 10 UVOT images for GRB 100111A, 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 = 247.04845, +15.55083 which is equivalent to:
```
RA (J2000): 16h 28m 11.63s
Dec (J2000): +15d 33' 03.0"
```
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 #10322
H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU), L. Vetere (PSU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 100111A (trigger #382399) (Vetere, et al., GCN Circ. 10317). The BAT ground-calculated position is RA, Dec = 247.029, 15.539 deg which is
```
   RA(J2000)  =  16h 28m 06.9s 
   Dec(J2000) = +15d 32' 19.1" 
```
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a weak peak at ~T-30 sec and the main FRED-like peak from ~T-10 sec and ending at ~T+25 sec. T90 (15-350 keV) is 12.9 +- 2.1 sec (estimated error including systematics).
The time-averaged spectrum from T-7.5 to T+8.7 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.69 +- 0.13. The fluence in the 15-150 keV band is 6.7 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.03 sec in the 15-150 keV band is 1.9 +- 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/382399/BA/
GCN Circular #10323
E. A. Hoversten (PSU) and L. Vetere (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 100111A 67 s after the BAT trigger (Vetere, et al., GCN Circ. 10317). A source is detected at 17.62 magnitudes in the initial white finding chart at the position RA, Dec (J2000) = 247.04833, 15.55064 which is equivalent to:
```
    RA(J2000)  =  16:28:11.60 = 247.04833
    DEC(J2000) = +15:33:02.3  = 15.55064
```
with a 90%-confidence error radius of about 0.51 arc sec. This position is 0.8 arcsec from the UVOT-enhanced XRT position (Beardmore, et al. GCN Circ. 10321) and the two positions agree within the error bars. The source faded by more than a magnitude in the white filter over the first orbit of observations. Additionally the source is detected in the b, u, and uvw1 filters, with a marginal 2.4-sigma detection in v and a 2.1-sigma detection in uvm2. Given the detection in the uvw1 filter the redshift of this burst is less than 1.9.
The observed magnitudes and 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the initial exposures are:
```
Filter   T_start(s)   T_stop(s)   Exp(s)          Mag
=============================================================
white        67          217        147      17.62 +/- 0.05
white       858         1007        147      18.73 +/- 0.10
v           609         1057         58         > 18.41
b           535          727         39      18.76 +/- 0.27
u           279          529        245      17.37 +/- 0.07
uvw1        658          851         38      18.57 +/- 0.36
uvm2        633          827         38         > 18.99
uvw2        584         1033         58         > 19.04
```
The values quoted above 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 Circular #10324
A. N. Morgan, S. B. Cenko, J. S. Bloom, (UC Berkeley), report:
We observed the field of GRB 100111A (Vetere et al., GCN 10317) with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at 2010-01-11 12:20:11 UT, ~8.12 hours after the Swift trigger. Observations were taken under good weather conditions but at high airmass before dawn. In mosaics (effective exposure time of ~2223 seconds) taken simultaneously in the J, H, and Ks filters, we do not detect the optical afterglow (Vetere et al., GCN 10317; Xu et al., GCN 10318; Hoversten et al., GCN 10323).
The preliminary photometry yields:
```
post_burst
t_mid(h)    exp(s)  filt    U. Limit (3 sig)
8.60        2223    J       > 19.0
8.60        2223    H       > 18.5
8.60        2223    Ks      > 18.0
```
All magnitudes given in the Vega system, calibrated to 2MASS. No correction for Galactic extinction has been made to the above reported values.
GCN Report 265.1
GCN_Report 265.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_265_1.pdf by L. Vetere at PSU titled: "Final Swift Observations on GRB 100111A"
GCN Circular #10822
A. Volnova (SAI MSU), M. Ibrahimov, R. Karimov (MAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the afterglow of the Swift GRB 100111A (Vetere et al. GCN 10317) with AZT-22 (1.5 m) telescope of Maidanak observatory (MAO) in R band on Jan. 12 (UT) (00:44 - 01:32) under good weather conditions with mean seeing of about 0.8 arcsec. The optical afterglow (Vetere et al. GCN 10317) is clearly detected in enhanced XRT error circle (Beardmore et al. GCN 10321). A photometry of combined image is based on several SDSS DR7 field stars:
```
T0+     Filter  Exp.    Mag.            UL
mid., days      seconds                 (3 sigma)


0.8687         R       8*300   22.92 +/- 0.18  23.56
```
Comparing with R-magnitude reported by Xu et al. (GCN 10318) (R=19.46+/-0.05 in 0.05 days) one can obtain power-law decay index of about 1.12.

Back to JG's homepage

Jochen Greiner, last update: 11-Jan-2010 [Disclaimer]