Gamma-ray Burst 150222A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 16:56:56 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     632180,   Seg_Num: 0
GRB_RA:          198.774d {+13h 15m 06s} (J2000),
                 198.973d {+13h 15m 54s} (current),
                 198.114d {+13h 12m 27s} (1950)
GRB_DEC:         -12.137d {-12d 08' 11"} (J2000),
                 -12.217d {-12d 12' 59"} (current),
                 -11.873d {-11d 52' 21"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3773 [cnts]    Image_Peak=203 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   147     E_range: 25-100 keV
BKG_INTEN:       23969 [cnts]
BKG_TIME:        60986.77 SOD {16:56:26.77} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17075 TJD;    53 DOY;   15/02/22
GRB_TIME:        61000.85 SOD {16:56:40.85} UT
GRB_PHI:          35.36 [deg]
GRB_THETA:        32.57 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     12.60 [sigma]
IMAGE_SIGNIF:    9.76 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +0  +0  +0 +66  +0 
SUN_POSTN:       335.65d {+22h 22m 36s}  -10.13d {-10d 07' 59"}
SUN_DIST:        131.51 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.05d {+01h 36m 11s}   +8.73d {+08d 43' 39"}
MOON_DIST:       173.91 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      312.01, 50.32 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      201.91, -3.88 [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 = 158.60,-19.49 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 16:58:25 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.135d {-12d 08' 04"} (J2000)
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61093.66 SOD {16:58:13.66} UT,   92.8 [sec] since BAT Trigger Time
COUNTS:          10    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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 17:00:31 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     632180,   Seg_Num: 0
GRB_RA:          198.774d {+13h 15m 06s} (J2000),
                 198.973d {+13h 15m 54s} (current),
                 198.114d {+13h 12m 27s} (1950)
GRB_DEC:         -12.137d {-12d 08' 11"} (J2000),
                 -12.217d {-12d 12' 59"} (current),
                 -11.873d {-11d 52' 21"} (1950)
GRB_DATE:        17075 TJD;    53 DOY;   15/02/22
GRB_TIME:        61000.85 SOD {16:56:40.85} UT
TRIGGER_INDEX:   147
GRB_PHI:          35.36 [deg]
GRB_THETA:        32.57 [deg]
DELTA_TIME:      32.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     12.60 [sigma]
IMAGE_SIGNIF:    9.76 [sigma]
LC_URL:          sw00632180000msb.lc
SUN_POSTN:       335.65d {+22h 22m 37s}  -10.13d {-10d 07' 55"}
SUN_DIST:        131.51 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.08d {+01h 36m 19s}   +8.74d {+08d 44' 15"}
MOON_DIST:       173.89 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      312.01, 50.32 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      201.91, -3.88 [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 = 158.60,-19.49 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 17:01:15 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.134d {-12d 08' 02"} (J2000)
POINT_ROLL:      115.645d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61096.93 SOD {16:58:16.93} UT,   96.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.477
N_STARS:         30
X_OFFSET:        548 [pixels]
Y_OFFSET:        510 [pixels]
X_MAX:           1507 [pixels]
Y_MAX:           1469 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00632180000msufc0096.fits
SUN_POSTN:       335.65d {+22h 22m 37s}  -10.13d {-10d 07' 55"}
SUN_DIST:        131.52 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.09d {+01h 36m 21s}   +8.74d {+08d 44' 22"}
MOON_DIST:       173.88 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 17:01:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.134d {-12d 08' 02"} (J2000)
POINT_ROLL:      115.645d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61096.93 SOD {16:58:16.93} UT,   96.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.477
N_STARS:         30
X_OFFSET:        548 [pixels]
Y_OFFSET:        510 [pixels]
X_MAX:           1507 [pixels]
Y_MAX:           1469 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00632180000msufc0096.fits
SUN_POSTN:       335.65d {+22h 22m 37s}  -10.13d {-10d 07' 55"}
SUN_DIST:        131.52 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.09d {+01h 36m 22s}   +8.74d {+08d 44' 25"}
MOON_DIST:       173.88 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.89 [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 22 Feb 15 17:02:41 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.134d {-12d 08' 02"} (J2000)
ROLL:            115.645d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61096.93 SOD {16:58:16.93} UT,   96.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446317110
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0110.fits
SUN_POSTN:       335.65d {+22h 22m 37s}  -10.13d {-10d 07' 54"}
SUN_DIST:        131.52 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.10d {+01h 36m 24s}   +8.74d {+08d 44' 37"}
MOON_DIST:       173.87 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.89 [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 22 Feb 15 17:03:12 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.134d {-12d 08' 02"} (J2000)
ROLL:            115.645d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61096.93 SOD {16:58:16.93} UT,   96.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446317110
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0110.fits
SUN_POSTN:       335.66d {+22h 22m 37s}  -10.13d {-10d 07' 53"}
SUN_DIST:        131.52 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.11d {+01h 36m 25s}   +8.74d {+08d 44' 42"}
MOON_DIST:       173.87 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.89 [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 22 Feb 15 17:05:51 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     632180,   Seg_Num: 0
GRB_RA:          198.7853d {+13h 15m 08.47s} (J2000),
                 198.9852d {+13h 15m 56.45s} (current),
                 198.1260d {+13h 12m 30.24s} (1950)
GRB_DEC:         -12.1515d {-12d 09' 05.4"} (J2000),
                 -12.2313d {-12d 13' 52.5"} (current),
                 -11.8874d {-11d 53' 14.6"} (1950)
GRB_ERROR:       4.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61251.00 SOD {17:00:51.00} UT,   250.2 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 51"}
SUN_DIST:        131.50 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.13d {+01h 36m 32s}   +8.75d {+08d 45' 09"}
MOON_DIST:       173.86 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      312.02, 50.30 [deg] galactic lon,lat of the burst
ECL_COORDS:      201.93, -3.89 [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 22 Feb 15 17:09:26 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.763d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
POINT_ROLL:      115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61308.99 SOD {17:01:48.99} UT,   308.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.695
N_STARS:         68
X_OFFSET:        308 [pixels]
Y_OFFSET:        270 [pixels]
X_MAX:           1747 [pixels]
Y_MAX:           1709 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00632180000msufc0308.fits
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 47"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.17d {+01h 36m 40s}   +8.76d {+08d 45' 45"}
MOON_DIST:       173.83 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 17:09:46 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.763d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
POINT_ROLL:      115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61308.99 SOD {17:01:48.99} UT,   308.1 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.695
N_STARS:         68
X_OFFSET:        308 [pixels]
Y_OFFSET:        270 [pixels]
X_MAX:           1747 [pixels]
Y_MAX:           1709 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00632180000msufc0308.fits
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 47"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.17d {+01h 36m 41s}   +8.76d {+08d 45' 48"}
MOON_DIST:       173.83 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 22 Feb 15 17:10:16 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     632180,   Seg_Num: 0
GRB_RA:          198.7863d {+13h 15m 08.71s} (J2000),
                 198.9862d {+13h 15m 56.69s} (current),
                 198.1270d {+13h 12m 30.48s} (1950)
GRB_DEC:         -12.1516d {-12d 09' 05.7"} (J2000),
                 -12.2314d {-12d 13' 52.9"} (current),
                 -11.8875d {-11d 53' 15.0"} (1950)
GRB_ERROR:       2.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61251.00 SOD {17:00:51.00} UT,   250.2 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 47"}
SUN_DIST:        131.50 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.17d {+01h 36m 42s}   +8.76d {+08d 45' 53"}
MOON_DIST:       173.83 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      312.02, 50.30 [deg] galactic lon,lat of the burst
ECL_COORDS:      201.93, -3.89 [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:     Sun 22 Feb 15 17:10:49 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.763d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
ROLL:            115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61308.99 SOD {17:01:48.99} UT,   308.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     446317322
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0322.fits
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 46"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.18d {+01h 36m 43s}   +8.77d {+08d 45' 59"}
MOON_DIST:       173.82 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 22 Feb 15 17:11:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.763d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
ROLL:            115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61308.99 SOD {17:01:48.99} UT,   308.1 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     446317322
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0322.fits
SUN_POSTN:       335.66d {+22h 22m 38s}  -10.13d {-10d 07' 46"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.18d {+01h 36m 44s}   +8.77d {+08d 46' 01"}
MOON_DIST:       173.82 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 22 Feb 15 17:16:26 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
POINT_ROLL:      115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61864.18 SOD {17:11:04.18} UT,   863.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.236
N_STARS:         69
X_OFFSET:        308 [pixels]
Y_OFFSET:        270 [pixels]
X_MAX:           1747 [pixels]
Y_MAX:           1709 [pixels]
DET_THRESH:      17
PHOTO_THRESH:    10
SL_URL:          sw00632180000msufc0863.fits
SUN_POSTN:       335.66d {+22h 22m 39s}  -10.13d {-10d 07' 41"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.23d {+01h 36m 56s}   +8.78d {+08d 46' 55"}
MOON_DIST:       173.78 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 22 Feb 15 17:16:42 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
POINT_ROLL:      115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61864.18 SOD {17:11:04.18} UT,   863.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.236
N_STARS:         69
X_OFFSET:        308 [pixels]
Y_OFFSET:        270 [pixels]
X_MAX:           1747 [pixels]
Y_MAX:           1709 [pixels]
DET_THRESH:      17
PHOTO_THRESH:    10
SL_URL:          sw00632180000msufc0863.fits
SUN_POSTN:       335.66d {+22h 22m 39s}  -10.13d {-10d 07' 41"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.24d {+01h 36m 57s}   +8.78d {+08d 46' 58"}
MOON_DIST:       173.78 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 22 Feb 15 17:18:19 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
ROLL:            115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61864.18 SOD {17:11:04.18} UT,   863.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446317877
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0877.fits
SUN_POSTN:       335.67d {+22h 22m 40s}  -10.13d {-10d 07' 39"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.25d {+01h 37m 01s}   +8.79d {+08d 47' 14"}
MOON_DIST:       173.77 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 22 Feb 15 17:18:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     632180,   Seg_Num: 0
POINT_RA:        198.762d {+13h 15m 03s} (J2000)
POINT_DEC:       -12.132d {-12d 07' 55"} (J2000)
ROLL:            115.643d
IMG_START_DATE:  17075 TJD;    53 DOY;   15/02/22
IMG_START_TIME:  61864.18 SOD {17:11:04.18} UT,   863.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446317877
X_OFFSET:        867 [pixels]
Y_OFFSET:        829 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1027
Y_GRB_POS:       989
BINNING_INDEX:   1
IM_URL:          sw00632180000msuni0877.fits
SUN_POSTN:       335.67d {+22h 22m 40s}  -10.13d {-10d 07' 39"}
SUN_DIST:        131.53 [deg]   Sun_angle= 9.1 [hr] (West of Sun)
MOON_POSTN:       24.26d {+01h 37m 01s}   +8.79d {+08d 47' 16"}
MOON_DIST:       173.77 [deg]
MOON_ILLUM:      19 [%]
GAL_COORDS:      311.99, 50.32 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      201.90, -3.88 [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 #17486
M. G. Bernardini (INAF-OAB), S. D. Barthelmy (GSFC), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), A. Melandri (INAF-OAB), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 16:56:40 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 150222A (trigger=632180). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 198.774, -12.137 which is
```
   RA(J2000) = 13h 15m 06s
   Dec(J2000) = -12d 08' 11"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multiple-peaked structure with a duration of about 15 sec. The peak count rate was ~6000 counts/sec (15-350 keV), at ~6 sec after the trigger.
The XRT began observing the field at 16:58:13.6 UT, 92.8 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 198.7865, -12.1517 which is equivalent to:
```
   RA(J2000)  = 13h 15m 08.76s
   Dec(J2000) = -12d 09' 06.3"
```
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This location is 68 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 (3.31 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.9 (+2.52/-2.21) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 96 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05.
Burst Advocate for this burst is M. G. Bernardini (grazia.bernardini AT brera.inaf.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular #17487
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
E. Gorbovskoy, V. Lipunov, M.Pruzhinskaya, V.Kornilov, D.Kuvshinov, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, D.Denisenko, A.Sankovich Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University
V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
V.Krushinsky, I.Zalozhnih, A. Popov Ural Federal University, Yekaterinburg, Kourovka
D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory
Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka was pointed to the GRB150222A 58 sec after notice time and 76 sec after trigger time at 2015-02-22 16:57:57 UT in two polarizations. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (Bernardini et. al GCN 17486). The 5-sigma upper limit has been about 15.5 mag The observations made on high zenith distance (z=75 d). The message may be cited.
GCN Circular #17488
A. Klotz, D. Turpin (IRAP-CNRS-OMP), D. Macpherson (UWA/ICRAR), D. Coward (UWA), M. Boer, B. Gendre, K. Siellez, H. Dereli, O. Bardho (UNS-CNRS-OCA), A. Williams (PO-UWA), R. Martin (PO-UWA) report:
We imaged the field of GRB 150222A detected by SWIFT (trigger 632180) with the Zadko robotic telescope (D=100cm) located at the observatory - Gingin, Australia.
The observations started 55s after the GRB trigger (42s after the notice). The elevation of the field increased from 51 degrees above horizon and weather conditions were very good.
The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT at the XRT position (Bernardini et al. GCNC 17486) with a limiting magnitude of: t0+55s to t0+115s : Rlim = 18.5
The second image is 30.0s exposure in tracking mode: t0+134s to t0+164s : Rlim = 19.8
We co-added a series of exposures: t0+134s to t0+834s : Rlim = 21.5
Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction.
GCN Circular #17489
E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), I. Korobtsev (ISTP), M. Eselevich (ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of GRB 150222A (Bernardini et al., GCN 17486) with AZT-33IK telescope of Sayan observatory (Mondy) starting on Feb., 22 (UT) 17:48:56. We obtained 37 images in R-filter of 120 s exposure. Within the Swift-XRT error circle (Bernardini et al., GCN 17486) we marginally detected optical source with a magnitude of R=22.15+/-0.25 at 0.06201 days after trigger (mid time). Photometry of the source is based on nearby USNO-B1.0 (R2) stars. At this time we cannot confirm variability or fading nature of the source.
GCN Circular #17491
C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), M. G. Bernardini (INAF-OAB), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-60 to T+117 sec from the recent telemetry downlink, we report further analysis of BAT GRB 150222A (trigger #632180) (Bernardini, et al., GCN Circ. 17486). The BAT ground-calculated position is RA, Dec = 198.787, -12.151 deg which is
```
    RA(J2000)  =  13h 15m 09.0s
    Dec(J2000) = -12d 09' 02.0"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 48%.
The mask-weighted light curve shows a double-peaked structure, with a first peak from T+0 to T+3 sec and a second, larger peak from T+3 to T+18 sec, followed by lower level emission out to ~T+40 sec. T90 (15-350 keV) is 15.90 +- 7.32 sec (estimated error including systematics).
The time-averaged spectrum from T-0.14 to T+28.11 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.61 +- 0.08. The fluence in the 15-150 keV band is 2.2 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+5.62 sec in the 15-150 keV band is 4.7 +- 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/632180/BA/
GCN Circular #17493
D. Malesani (DARK/NBI), V. D'Elia (INAF/OAR and ASI/ASDC), P. D'Avanzo (INAF/OABr), A. Melandri (INAF/OABr), S. Covino (INAF/OABr), V. Lorenzi (INAF/TNG), Albar Garcia de Gurtubai Escudero (INAF/TNG), report on behalf of the CIBO collaboration:
We observed the field of GRB 150222A (Bernardini et al., GCN 17486) with the 3.6m TNG telescope equipped with the DOLoRes camera. Observations consisted of 4 images in the I band for a total of 20 min exposure. The seeing was poor (3.2").
No object is detected within the (currently unenhanced) XRT position, down to a limiting magnitude I > 22.3 (calibrated against nearby USNO stars). The mean time of the observation was 2015 Feb 23.055 UT, that is 8.4 hr after the GRB.
GCN Circular #17494
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 3503 s of XRT Photon Counting mode data and 6 UVOT images for GRB 150222A, 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 = 198.78648, -12.15200 which is equivalent to:
```
RA (J2000): 13h 15m 8.75s
Dec (J2000): -12d 09' 07.2"
```
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 #17495
A. Nicuesa Guelbenzu (TLS Tautenburg), P. Wiseman (MPE Garching), and J. Greiner (MPE Garching) report:
We observed the field of GRB 150222A (Swift trigger 632180; Bernardini et al., GCN 17486) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla Observatory (Chile).
Observations started at 03:39:15 UT on February 23, about 10 hours after the GRB trigger. Inside the enhanced X-ray error circle (Beardmore et al., GCN 17494) we detect a faint source at coordinates RA, DEC (J2000) = 13:15:08.75, -12:09:06.2 with an error of 0".5.
At a mean time of February 23, at 04:39:07 UT, we measure the following preliminary AB magnitude:
```
g' = 24.8 +/- 0.2.
r' = 24.6 +/- 0.3.
```
At present we cannot decide if this is the afterglow. Observations are ongoing.
Magnitudes are calibrated against GROND zeropoints (g'r'i'z') and are not corrected for the Galactic extinction in the direction of the burst.
GCN Circular #17498
C. Pagani (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), M. de Pasquale (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester) and M. G. Bernardini (INAF-OAB) report on behalf of the Swift-XRT team:
We have analysed 6.7 ks of XRT data for GRB 150222A (Bernardini et al. GCN Circ. 17486), from 76 s to 44.7 ks after the BAT trigger. The data comprise 221 s in Windowed Timing (WT) mode (the first 10 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 17494).
The light curve can be modelled with a power-law decay with a decay index of alpha=0.95 (+/-0.03). Some flaring activity is observed between T+250 s and T+650 s.
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.51 (+0.12, -0.11). The best-fitting absorption column is 4.7 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 3.3 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.45 (+0.19, -0.18) and a best-fitting absorption column of 5.8 (+1.0, -0.9) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.4 x 10^-11 (7.9 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     5.8 (+1.0, -0.9) x 10^21 cm^-2
Galactic foreground: 3.3 x 10^20 cm^-2
Excess significance: 10.0 sigma
Photon index:	     2.45 (+0.19, -0.18)
```
If the light curve continues to decay with a power-law decay index of 0.95, the count rate at T+24 hours will be 9.9 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.3 x 10^-13 (7.8 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/00632180.
This circular is an official product of the Swift-XRT team.
GCN Circular #17499
N. P. M. Kuin (UCL-MSSL) and M. G. Bernardini (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150222A 96 s after the BAT trigger (Bernardini et al., GCN Circ. 17486). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 17494) 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            96          246          147         >20.8
u_FC               308          558          246         >20.7
white               96         6906          746         >21.3
v                  639         5881          274         >19.9
b                  564         6702          452         >20.9
u                  308         6496          678         >20.8
w1                 689         6292          432         >20.0
m2                 836         6086          413         >20.4
w2                1019         6994          297         >20.5
```
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 Circular #17500
Antonio de Ugarte Postigo (IAA-CSIC, DARK/NBI), Christina Thoene (IAA-CSIC), and Victor Casanova (IAA-CSIC) report on behalf of a larger collaboration:
We observed the field of GRB 150222A (Bernardini et al., GCN 17486) with the 1.5 m telescope at Sierra Nevada Observatory (Granada, Spain). Observations consisted of 34x300s in I-band and ranged from 2:46 to 5:44 UT (mid epoch at 4:15 UT, or 11.31 hr after the burst trigger). Observing conditions were poor, with a seeing of 2.9". We do not detect the optical counterpart candidate reported by Mazaeva et al. (GCN 17489) and Nicuesa Guelbenzu et al. (GCN 17495) or any other object within the enhanced XRT error circle (Beardmore et al. GCN 17494). The 3-sigma limit of the combined image is I(Vega) = 22.5 mag, as compared with USNOB-1.0 stars.
Considering an optical decay slope of alpha ~ 1.1 (where F_nu ~ t^(-alpha)) between the epochs of Mazaeva et al. and Nicuesa Guelbenzu et al., and a typical GRB colour, our observation is consistent with the expected brightness and is also consistent with the non-detections reported by other groups (Ivanov et al. GCN 17487; Klotz et al. GCN 17488; Malesani et al. GCN 17493; Kuin et al. GCN 17499)
GCN Circular #17506
A. Nicuesa Guelbenzu (TLS Tautenburg), P. Wiseman, P. Schady and J. Greiner (all MPE Garching) report on behalf of the GROND team:
We continued to observe the field of GRB 150222A (Swift trigger 632180; Bernadini et al., GCN 17486) for a second night, simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).
Observations began at 06:25:38 UT on February 24, ~34 hours after the GRB trigger. They were performed at an average seeing of 1.3" and at an average airmass of 1.1.
In 106 min of total exposures in g'r'i'z', we detect a source in all optical bands towards the north-eastern edge of the the 1.7" enhanced Swift-XRT error circle (Beardmore et al., GCN 17494) , at a position consistent with that reported in Nicuesa Guelbenzu et al. (GCN 17495). In 115 min of total NIR exposures in the JHK bands, no source is detected within the enhanced XRT error circle.
We detect no fading of the source between the two epochs, and therefore suggest that this is not the afterglow, but could be the host galaxy instead, unless we caught an afterglow plateau phase.
GCN Circular #17567
V. Rumyantsev (CrAO), E. Mazaeva (IKI), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB GRB 150222A (Bernardini et al., GCN 17486) with ZTSh telescope of CrAO observatory starting on Feb. 22 (UT) 23:19:54. We took several images in R-filter of 120 s exposure under non-optimal weather conditions and mean seeing of 4". Within enhanced XRT position (Beardmore et al., GCN 17494) we detect a source in coordinates (J2000) 13 15 08.74 -12 09 07.2 with uncertainty of 0.4 arcsec in both coordinates. The source position is coincident with the optical afterglow candidate (Nicuesa Guelbenzu et al., GCNs 17495, GCN 17506). Photometry of the source in a combined image is following
```
Date       UT start,  t-t0     Filter   Exp.    OT   OT_err UL(3sigma)
                       (mid, days)        (s)

2015-02-22 23:19:54   0.2913   R        34*120  23.0 0.3    23.3
```
The photometry is based on USNO-B1.0 star 0778-0337957 (J2000) 13 15 05.41 -12 08 17.5 assuming R2=15.31
Taking into account photometry of the source r' = 24.6+/-0.3 at ~0.42 days reported by Nicuesa Guelbenzu et al. (GCN 17495) one could suggest the source is the optical afterglow of GRB 150222A.
The source reported in GCN 17489 (Mazaeva et al) is clearly visible in coordinates (J2000) 13 15 08.30 -12 08 57.5 with uncertainty of 0.4 arcsec in both coordinates. A photometry of the source is R=22.12+/-0.12.

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Jochen Greiner, last update: 11-Mar-2015 [Disclaimer]