Gamma-ray Burst 150301B

(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 01 Mar 15 19:38:19 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     633180,   Seg_Num: 0
GRB_RA:           89.157d {+05h 56m 38s} (J2000),
                  89.217d {+05h 56m 52s} (current),
                  88.962d {+05h 55m 51s} (1950)
GRB_DEC:         -57.977d {-57d 58' 37"} (J2000),
                 -57.976d {-57d 58' 32"} (current),
                 -57.982d {-57d 58' 53"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       2319 [cnts]    Image_Peak=181 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   124     E_range: 25-100 keV
BKG_INTEN:       24749 [cnts]
BKG_TIME:        70666.74 SOD {19:37:46.74} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17082 TJD;    60 DOY;   15/03/01
GRB_TIME:        70684.02 SOD {19:38:04.02} UT
GRB_PHI:         -27.56 [deg]
GRB_THETA:        35.77 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     17.88 [sigma]
IMAGE_SIGNIF:    10.73 [sigma]
MERIT_PARAMS:     +1  +0  +0  -1  +2  +0  +0  +0  +4  +0 
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 44"}
SUN_DIST:         92.41 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      118.97d {+07h 55m 53s}  +15.70d {+15d 41' 45"}
MOON_DIST:        77.65 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.89 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       87.01,-81.41 [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 = 60.33,-19.63 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=446931487).

red DSS finding chart ps-file

GCN NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Sun 01 Mar 15 19:38:53 UT 
NOTICE_TYPE:    INTEGRAL SPI ACS Trigger
TRIGGER_NUM:    6902,   Sub_Num: 0
GRB_INTEN:      9.24 [sigma]   
GRB_TIME:       70683.36 SOD {19:38:03.36} UT
GRB_DATE:       17082 TJD;    60 DOY;   15/03/01
COMMENTS:       INTEGRAL SPI_ACS GRB Trigger.
COMMENTS:       Time_Scale=2.0000 and Time_Error=1.0000.
COMMENTS:
COMMENTS:       NOTE: This SPIACS event is temporally(1.0<100sec) coincident with the FERMI_GBM event (trignum=446931487).
COMMENTS:
COMMENTS:       The SPIACS lightcurve can be found at:
COMMENTS:       ftp://isdcarc.unige.ch/arc/FTP/ibas/spiacs/2015-03/2015-03-01T19-38-03.1874-29951-27536-0.lc

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:38:59 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      58
TRIGGER_NUM:     446931487
GRB_RA:           86.200d {+05h 44m 48s} (J2000),
                  86.271d {+05h 45m 05s} (current),
                  85.967d {+05h 43m 52s} (1950)
GRB_DEC:         -55.690d {-55d 41' 23"} (J2000),
                 -55.684d {-55d 41' 03"} (current),
                 -55.709d {-55d 42' 31"} (1950)
GRB_ERROR:       2.41 [deg radius, statistical only]
DATA_SIGNIF:     19.50 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        17082 TJD;    60 DOY;   15/03/01
GRB_TIME:        70684.51 SOD {19:38:04.51} UT
GRB_PHI:         273.00 [deg]
GRB_THETA:        42.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 43"}
SUN_DIST:         91.53 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      118.98d {+07h 55m 54s}  +15.69d {+15d 41' 42"}
MOON_DIST:        76.51 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      263.70,-31.36 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       78.73,-78.98 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn150301818/quicklook/glg_lc_medres34_bn150301818.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(1.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=6902).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:38:32 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      48
TRIGGER_NUM:     446931487
GRB_RA:           92.683d {+06h 10m 44s} (J2000),
                  92.720d {+06h 10m 53s} (current),
                  92.561d {+06h 10m 15s} (1950)
GRB_DEC:         -61.783d {-61d 46' 59"} (J2000),
                 -61.787d {-61d 47' 13"} (current),
                 -61.771d {-61d 46' 13"} (1950)
GRB_ERROR:       9.40 [deg radius, statistical plus systematic]
GRB_INTEN:       198 [cnts/sec]
DATA_SIGNIF:     8.70 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        17082 TJD;    60 DOY;   15/03/01
GRB_TIME:        70684.51 SOD {19:38:04.51} UT
GRB_PHI:         272.00 [deg]
GRB_THETA:        35.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      1.27
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      58%  GRB
2nd_MOST_LIKELY:  41%  Distant Particles
DETECTORS:       0,0,0, 1,0,0, 1,1,0, 0,0,0, 0,0,
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 44"}
SUN_DIST:         92.77 [deg]   Sun_angle= -7.4 [hr] (East of Sun)
MOON_POSTN:      118.97d {+07h 55m 54s}  +15.70d {+15d 41' 44"}
MOON_DIST:        80.22 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      270.98,-28.43 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      104.97,-85.08 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn150301818/quicklook/glg_lc_medres34_bn150301818.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 113.32,-25.28 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=633180).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:38:45 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      59
TRIGGER_NUM:     446931487
GRB_RA:           86.400d {+05h 45m 36s} (J2000),
                  86.461d {+05h 45m 51s} (current),
                  86.201d {+05h 44m 48s} (1950)
GRB_DEC:         -57.783d {-57d 46' 59"} (J2000),
                 -57.778d {-57d 46' 40"} (current),
                 -57.801d {-57d 48' 04"} (1950)
GRB_ERROR:       7.13 [deg radius, statistical plus systematic]
GRB_INTEN:       199 [cnts/sec]
DATA_SIGNIF:     18.20 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17082 TJD;    60 DOY;   15/03/01
GRB_TIME:        70684.51 SOD {19:38:04.51} UT
GRB_PHI:         274.00 [deg]
GRB_THETA:        40.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.16
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      50%  GRB
2nd_MOST_LIKELY:  49%  Distant Particles
DETECTORS:       0,0,0, 1,0,0, 1,1,0, 0,0,0, 0,0,
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 44"}
SUN_DIST:         91.06 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      118.98d {+07h 55m 54s}  +15.70d {+15d 41' 43"}
MOON_DIST:        78.23 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.16,-31.35 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       77.55,-81.07 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn150301818/quicklook/glg_lc_medres34_bn150301818.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 113.32,-25.28 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=633180).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:42:37 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.182d {+05h 56m 44s} (J2000)
POINT_DEC:       -57.974d {-57d 58' 25"} (J2000)
POINT_ROLL:      251.804d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70770.00 SOD {19:39:30.00} UT,   86.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.308
N_STARS:         59
X_OFFSET:        583 [pixels]
Y_OFFSET:        527 [pixels]
X_MAX:           1542 [pixels]
Y_MAX:           1486 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00633180000msufc0085.fits
SUN_POSTN:       342.37d {+22h 49m 30s}   -7.48d {-07d 28' 40"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.01d {+07h 56m 02s}  +15.69d {+15d 41' 24"}
MOON_DIST:        77.65 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.10,-81.41 [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 01 Mar 15 19:42:21 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.182d {+05h 56m 44s} (J2000)
POINT_DEC:       -57.974d {-57d 58' 25"} (J2000)
POINT_ROLL:      251.804d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70770.00 SOD {19:39:30.00} UT,   86.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.308
N_STARS:         59
X_OFFSET:        583 [pixels]
Y_OFFSET:        527 [pixels]
X_MAX:           1542 [pixels]
Y_MAX:           1486 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00633180000msufc0085.fits
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 40"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.01d {+07h 56m 01s}  +15.69d {+15d 41' 25"}
MOON_DIST:        77.65 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.10,-81.41 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:39:33 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.182d {+05h 56m 44s} (J2000)
POINT_DEC:       -57.974d {-57d 58' 27"} (J2000)
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70766.46 SOD {19:39:26.46} UT,   82.4 [sec] since BAT Trigger Time
COUNTS:          15    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 01 Mar 15 19:50:37 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.186d {+05h 56m 45s} (J2000)
POINT_DEC:       -57.976d {-57d 58' 33"} (J2000)
POINT_ROLL:      251.801d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70982.05 SOD {19:43:02.05} UT,   298.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.375
N_STARS:         97
X_OFFSET:        343 [pixels]
Y_OFFSET:        287 [pixels]
X_MAX:           1782 [pixels]
Y_MAX:           1726 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    2
SL_URL:          sw00633180000msufc0298.fits
SUN_POSTN:       342.38d {+22h 49m 31s}   -7.48d {-07d 28' 32"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.08d {+07h 56m 18s}  +15.68d {+15d 40' 44"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.11,-81.41 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:41:41 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     633180,   Seg_Num: 0
GRB_RA:           89.157d {+05h 56m 38s} (J2000),
                  89.217d {+05h 56m 52s} (current),
                  88.962d {+05h 55m 51s} (1950)
GRB_DEC:         -57.977d {-57d 58' 37"} (J2000),
                 -57.976d {-57d 58' 32"} (current),
                 -57.982d {-57d 58' 53"} (1950)
GRB_DATE:        17082 TJD;    60 DOY;   15/03/01
GRB_TIME:        70684.02 SOD {19:38:04.02} UT
TRIGGER_INDEX:   124
GRB_PHI:         -27.56 [deg]
GRB_THETA:        35.77 [deg]
DELTA_TIME:      32.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     17.88 [sigma]
IMAGE_SIGNIF:    10.73 [sigma]
LC_URL:          sw00633180000msb.lc
SUN_POSTN:       342.37d {+22h 49m 29s}   -7.48d {-07d 28' 41"}
SUN_DIST:         92.41 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.00d {+07h 56m 00s}  +15.69d {+15d 41' 28"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.89 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       87.01,-81.41 [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 = 60.33,-19.63 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:52:52 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     633180,   Seg_Num: 0
GRB_RA:           89.1660d {+05h 56m 39.83s} (J2000),
                  89.2254d {+05h 56m 54.08s} (current),
                  88.9705d {+05h 55m 52.91s} (1950)
GRB_DEC:         -57.9695d {-57d 58' 10.1"} (J2000),
                 -57.9683d {-57d 58' 05.9"} (current),
                 -57.9740d {-57d 58' 26.4"} (1950)
GRB_ERROR:       0.6 [arcsec radius, statistical only]
GRB_MAG:         16.21 +/- 0.14 [mag]
FILTER:          10, White
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70769.00 SOD {19:39:29.00} UT,   85.0 [sec] since BAT Trigger Time
SUN_POSTN:       342.38d {+22h 49m 31s}   -7.48d {-07d 28' 30"}
SUN_DIST:         92.41 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.10d {+07h 56m 23s}  +15.68d {+15d 40' 33"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.89 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       87.04,-81.40 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 01 Mar 15 19:43:42 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.182d {+05h 56m 44s} (J2000)
POINT_DEC:       -57.974d {-57d 58' 25"} (J2000)
ROLL:            251.804d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70770.00 SOD {19:39:30.00} UT,   86.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446931583
X_OFFSET:        902 [pixels]
Y_OFFSET:        846 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1062
Y_GRB_POS:       1006
BINNING_INDEX:   1
IM_URL:          sw00633180000msuni0099.fits
SUN_POSTN:       342.37d {+22h 49m 30s}   -7.48d {-07d 28' 39"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.02d {+07h 56m 04s}  +15.69d {+15d 41' 18"}
MOON_DIST:        77.65 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.10,-81.41 [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 01 Mar 15 19:43:54 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.182d {+05h 56m 44s} (J2000)
POINT_DEC:       -57.974d {-57d 58' 25"} (J2000)
ROLL:            251.804d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70770.00 SOD {19:39:30.00} UT,   86.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     446931583
X_OFFSET:        902 [pixels]
Y_OFFSET:        846 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1062
Y_GRB_POS:       1006
BINNING_INDEX:   1
IM_URL:          sw00633180000msuni0099.fits
SUN_POSTN:       342.37d {+22h 49m 30s}   -7.48d {-07d 28' 39"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.02d {+07h 56m 05s}  +15.69d {+15d 41' 17"}
MOON_DIST:        77.65 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.10,-81.41 [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 01 Mar 15 19:52:01 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.186d {+05h 56m 45s} (J2000)
POINT_DEC:       -57.976d {-57d 58' 33"} (J2000)
ROLL:            251.801d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70982.05 SOD {19:43:02.05} UT,   298.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     446931795
X_OFFSET:        902 [pixels]
Y_OFFSET:        846 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1062
Y_GRB_POS:       1006
BINNING_INDEX:   1
IM_URL:          sw00633180000msuni0312.fits
SUN_POSTN:       342.38d {+22h 49m 31s}   -7.48d {-07d 28' 31"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.09d {+07h 56m 21s}  +15.68d {+15d 40' 37"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.11,-81.41 [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 01 Mar 15 19:50:57 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.186d {+05h 56m 45s} (J2000)
POINT_DEC:       -57.976d {-57d 58' 33"} (J2000)
POINT_ROLL:      251.801d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70982.05 SOD {19:43:02.05} UT,   298.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.375
N_STARS:         97
X_OFFSET:        343 [pixels]
Y_OFFSET:        287 [pixels]
X_MAX:           1782 [pixels]
Y_MAX:           1726 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    2
SL_URL:          sw00633180000msufc0298.fits
SUN_POSTN:       342.38d {+22h 49m 31s}   -7.48d {-07d 28' 32"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.08d {+07h 56m 19s}  +15.68d {+15d 40' 42"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.11,-81.41 [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 01 Mar 15 19:51:49 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     633180,   Seg_Num: 0
POINT_RA:         89.186d {+05h 56m 45s} (J2000)
POINT_DEC:       -57.976d {-57d 58' 33"} (J2000)
ROLL:            251.801d
IMG_START_DATE:  17082 TJD;    60 DOY;   15/03/01
IMG_START_TIME:  70982.05 SOD {19:43:02.05} UT,   298.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     446931795
X_OFFSET:        902 [pixels]
Y_OFFSET:        846 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1062
Y_GRB_POS:       1006
BINNING_INDEX:   1
IM_URL:          sw00633180000msuni0312.fits
SUN_POSTN:       342.38d {+22h 49m 31s}   -7.48d {-07d 28' 31"}
SUN_DIST:         92.42 [deg]   Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN:      119.09d {+07h 56m 21s}  +15.68d {+15d 40' 38"}
MOON_DIST:        77.66 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      266.47,-29.88 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       87.11,-81.41 [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 Circular #17515
A. Y. Lien (GSFC/UMBC), D. N. Burrows (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), M. De Pasquale (INAF-IASFPA), A. Maselli (INAF-IASFPA), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 19:38:04 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 150301B (trigger=633180). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 89.157, -57.977 which is
```
   RA(J2000) = 05h 56m 38s
   Dec(J2000) = -57d 58' 37"
```
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 20 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 19:39:26.4 UT, 82.4 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 89.16636, -57.97051 which is equivalent to:
```
   RA(J2000)  = 05h 56m 39.93s
   Dec(J2000) = -57d 58' 13.8"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 29 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 consistent with the Galactic value of 6.16 x 10^20 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 85 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	05:56:39.86 =  89.16608
  DEC(J2000) = -57:58:10.4  = -57.96956
```
with a 90%-confidence error radius of about 0.61 arc sec. This position is 31.9 arc sec. from the center of the BAT error circle. The estimated magnitude is 16.22 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.08.
Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov). 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 #17518
D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory
E. Gorbovskoy, V. Lipunov, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Kuvshinov, 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
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 SAAO was pointed to the GRB150301.82 (Lien et al, GCN 17515) 60 sec after notice time and 79 sec after trigger time at 2015-03-01 19:39:23 UT in two polarizations. On our first (10s exposure) set we found 1 optical transient within SWIFT error-box (ra=05 56 37 dec=-57 58 35 r=0.050000).
```
                      T_start      RA            DEC     Exp     unfiltered
                          s                                      magnitude
  2015-03-01 19:39:23   79.0   05h 56m 39.94s  -57d 58m  10.0s     15.3
```
The error is about 0.5 arcsec. This position is coincidet with UVOT data. We detected OT before maximum brightness. The 5-sigma upper limit has been about 16.8 mag . The telegram is generated automatically. We have number of the images after maximum in two polarizations. The reduction is continuated. The message may be cited.
GCN Circular #17520
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 386 s of XRT Photon Counting mode data and 1 UVOT images for GRB 150301B, 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 = 89.16660, -57.96950 which is equivalent to:
```
RA (J2000): 05h 56m 39.98s
Dec (J2000): -57d 58' 10.2"
```
with an uncertainty of 1.8 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 #17522
D. A. Kann (TLS Tautenburg), C. Delvaux and J. Greiner (both MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 150301B (Swift trigger 633180; Lien et al., GCN #17515) 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 started at 00:09 UT on 2015-03-02, 4.5 hrs after the GRB trigger. They were performed at an average seeing of 1".0 and at an average airmass of 1.1.
We detect the optical afterglow candidate reported by Lien et al. (GCN #17515) and Buckley et al. (GCN #17518).
Based on 7.7 min of total exposure time in g'r'i'z' and 8.0 min in JHK, centered 5 hrs after the GRB, we estimate the following preliminary magnitudes (all in AB system):
```
g' = 21.7 +/- 0.2 mag,
r' = 21.4 +/- 0.1 mag,
i' = 21.2 +/- 0.1 mag,
z' = 21.0 +/- 0.1 mag,
J = 20.5 +/- 0.3 mag,
H = 20.6 +/- 0.4 mag, and
K > 17.9 mag.
```
Given magnitudes are calibrated against GROND zeropoints (g'r'i'z') as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.08 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular #17523
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), T. Kruehler (ESO), H. Flores (GEPI/Obs. de Paris), and J.P.U. Fynbo (DARK/NBI) report on behalf of a larger collaboration:
We observed the afterglow of GRB 150301B (Lien et al. GCN 17515, Buckley et al. GCN 17518, Kann et al. GCN 17522) with X-shooter at the Very Large Telescope (Paranal Observatory, Chile). Observations started at 00:45 UT (5.12 hr after the burst), and consisted of 6x600 s exposures covering the spectral range between 3 000 and 18 000 Angstroms.
In the acquisition image the afterglow is detected with R(Vega) = 21.0 mag, as compared to stars of the USNOB-1.0 catalogue.
On a preliminary reduction we detect a weak continuum with absorption features of FeII, MgII and MgI at a common redshift of z = 1.5169, which we suggest as the redshift of the GRB.
We acknowledge the excellent support provided by Paranal staff, and in particular Andrea Mehner, Tayyaba Zafar, and Marcelo Lopez.
GCN Circular #17524
T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), (i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 150301B (trigger #633180) (Lien, et al., GCN Circ. 17515). The BAT ground-calculated position is RA, Dec = 89.159, -57.969 deg which is
```
  RA(J2000)  =  05h 56m 38.3s
  Dec(J2000) = -57d 58' 07.8"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 62%.
The mask-weighted light curve shows a single-peaked structure that starts at ~ T0, peaks at ~ T+3 s, and ends at ~ T+16 s. T90 (15-350 keV) is 12.44 +- 1.49 sec (estimated error including systematics).
The time-averaged spectrum from T-0.34 to T+15.62 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.46 +- 0.07. The fluence in the 15-150 keV band is 1.8 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+3.65 sec in the 15-150 keV band is 3.0 +- 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/633180/BA/
GCN Circular #17525
E. Burns (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 19:38:04.51 UT on 01 March 2015, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 150301B (trigger 446931487/150301818) which was also detected by the Swift/BAT (Lien et al. 2015, GCN 17515). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 39 degrees.
The GBM light curve consists of one main peak with a duration (T90) of about 13 s (50-300 keV). The time-averaged spectrum from T0-2.560 s to T0+13.824 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.2 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 256 +/- 32 keV. A Band function fits the spectrum equally well with Epeak= 180 +/- 38 keV, alpha = -1.1 +/- 0.1 and beta = -2.0 +/- 0.2.
The event fluence (10-1000 keV) in this time interval is (4.4 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+2.560 s in the 10-1000 keV band is 4.5 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #17530
C. Guidorzi (U. Ferrara), J. Japelj, A. Gomboc (U. Ljubljana), C.G. Mundell (U. Bath), on behalf of a large collaboration report:
One of the Las Cumbres Observatory 1-m telescopes in Sutherland (South Africa) began observing Swift and Fermi GRB 150301B (Lien et al. GCN 17515; Burns et al. GCN 17525) on March 01 at 20:07:30 UT, i.e. ~29.4 minutes after the BAT trigger with the r', i', and g' filters.
We detect the optical afterglow (Lien et al. GCN 17515; Buckley et al. GCN 7518; Kann et al. GCN 17522; de Ugarte Postigo et al. GCN 17523) with the following magnitudes:
```
Mid time from  Total Exp   Filter    Magnitude
trigger (min)   (s)
-------------------------------------------------
37.7            360         r'     18.85 +- 0.25
42.3            360         i'     18.5  +- 0.3
-------------------------------------------------
```
Values have been calibrated against nearby USNOB-1 stars (R2 and I). Compared with earlier (Buckley et el.) and later (Kann et al.) observations, our values suggest an overall power-law decay index ~1.
GCN Circular #17531
M. M. Chester (PSU) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150301B 86 s after the BAT trigger (Lien et al., GCN Circ. 17515). A fading source consistent with the XRT position (Evans et al. GCN Circ. 17520) and the optical transient reported by Buckley et al. (GCN Circ. 17518) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
   RA  (J2000) =  05:56:39.89 =  89.16622 (deg.)
   Dec (J2000) = -57:58:10.4  = -57.96955 (deg.)
```
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits for the White finding chart and subsequent exposures 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_FC            86          236          147         16.2 +/- 0.1
white             3986         4121          133        >20.2
v                 5833         6033          197        >19.7
b                 3782         3982          197        >19.6
u                  298          543          241         17.1 +/- 0.1
w1                6243        10068          579        >19.9
m2                6038         6237          197        >19.8
w2                5628        16054          963        >21.6
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.08 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #17533
A. Maselli (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), A. Amaral-Rogers (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and A.Y. Lien report on behalf of the Swift-XRT team:
We have analysed 5.7 ks of XRT data for GRB 150301B (Lien et al. GCN Circ. 17515), from 67 s to 69.5 ks after the BAT trigger. The data comprise 67 s in Windowed Timing (WT) mode (the first 9 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 Evans et al. (GCN Circ. 17520).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.11 (+0.05, -0.04).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.81 (+0.18, -0.10). The best-fitting absorption column is consistent with the Galactic value of 6.2 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (4.2 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Galactic foreground: 6.2 x 10^20 cm^-2
Intrinsic column:    6 (+/-14) x 10^20 cm^-2 at z=1.5169
Photon index:	     1.81 (+0.18, -0.10)
```
If the light curve continues to decay with a power-law decay index of 1.11, the count rate at T+24 hours will be 3.3 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x 10^-13 (1.4 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/00633180.
This circular is an official product of the Swift-XRT team.
1511.02641 from 10 Nov 15
E. S. Gorbovskoy et al.: Early polarization observations of the optical emission of gamma-ray bursts: GRB150301B and GRB150413A
We report early optical linear polarization observations of two gamma-ray bursts made with the MASTER robotic telescope network. We found the minimum polarization for GRB150301B to be 8% at the beginning of the initial stage, whereas we detected no polarization for GRB150413A either at the rising branch or after the burst reached the power-law afterglow stage. This is the earliest measurement of the polarization (in cosmological rest frame) of gamma-ray bursts. The primary intent of the paper is to discover optical emission and publish extremely rare (unique) high-quality light curves of the prompt optical emission of gamma-ray bursts during the non-monotonic stage of their evolution. We report that our team has discovered the optical counterpart of one of the bursts, GRB150413A.

Back to JG's homepage

Jochen Greiner, last update: 10-Nov-2015 [Disclaimer]