Gamma-ray Burst 160325A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:00:19 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.597d {+01h 02m 23s} (J2000),
                  15.726d {+01h 02m 54s} (current),
                  15.195d {+01h 00m 47s} (1950)
GRB_DEC:         -72.706d {-72d 42' 22"} (J2000),
                 -72.619d {-72d 37' 08"} (current),
                 -72.975d {-72d 58' 28"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3117 [cnts]    Image_Peak=230 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   124     E_range: 25-100 keV
BKG_INTEN:       30623 [cnts]
BKG_TIME:        25191.97 SOD {06:59:51.97} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25203.61 SOD {07:00:03.61} UT
GRB_PHI:           8.44 [deg]
GRB_THETA:        19.89 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     25.27 [sigma]
IMAGE_SIGNIF:    10.49 [sigma]
MERIT_PARAMS:     +1  +0  +0  -1  +2  +0  +0  +0 -25  +0 
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 45"}
SUN_DIST:         74.96 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.68d {+13h 34m 44s}   -6.77d {-06d 46' 08"}
MOON_DIST:       100.44 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.40 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      313.05,-65.20 [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 = 32.35,-19.53 [deg].
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(42.0<100sec) coincident with the FERMI_GBM event (trignum=480581965).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 25 Mar 16 06:59:46 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     480581965
GRB_RA:            4.783d {+00h 19m 08s} (J2000),
                   4.962d {+00h 19m 51s} (current),
                   4.226d {+00h 16m 54s} (1950)
GRB_DEC:         -75.167d {-75d 10' 00"} (J2000),
                 -75.077d {-75d 04' 35"} (current),
                 -75.444d {-75d 26' 38"} (1950)
GRB_ERROR:       16.33 [deg radius, statistical plus systematic]
GRB_INTEN:       68 [cnts/sec]
DATA_SIGNIF:     5.20 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25161.51 SOD {06:59:21.51} UT
GRB_PHI:         150.00 [deg]
GRB_THETA:        10.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.74
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      86%  GRB
2nd_MOST_LIKELY:  11%  Distant Particles
DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 44"}
SUN_DIST:         77.09 [deg]   Sun_angle= -0.0 [hr] (East of Sun)
MOON_POSTN:      203.68d {+13h 34m 43s}   -6.77d {-06d 46' 04"}
MOON_DIST:        97.37 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      305.70,-41.79 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      304.96,-63.56 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160325291/quicklook/glg_lc_medres34_bn160325291.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 119.27,-20.08 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 25 Mar 16 06:59:55 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      58
TRIGGER_NUM:     480581965
GRB_RA:            5.417d {+00h 21m 40s} (J2000),
                   5.592d {+00h 22m 22s} (current),
                   4.873d {+00h 19m 29s} (1950)
GRB_DEC:         -75.350d {-75d 20' 59"} (J2000),
                 -75.260d {-75d 15' 35"} (current),
                 -75.627d {-75d 37' 37"} (1950)
GRB_ERROR:       5.53 [deg radius, statistical plus systematic]
GRB_INTEN:       394 [cnts/sec]
DATA_SIGNIF:     37.40 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25161.51 SOD {06:59:21.51} UT
GRB_PHI:         150.00 [deg]
GRB_THETA:        10.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.71
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      97%  GRB
2nd_MOST_LIKELY:   2%  Generic Transient
DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 44"}
SUN_DIST:         77.27 [deg]   Sun_angle= -0.1 [hr] (East of Sun)
MOON_POSTN:      203.68d {+13h 34m 43s}   -6.77d {-06d 46' 05"}
MOON_DIST:        97.25 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      305.44,-41.63 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      304.75,-63.79 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160325291/quicklook/glg_lc_medres34_bn160325291.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 119.27,-20.08 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 25 Mar 16 06:59:58 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      57
TRIGGER_NUM:     480581965
GRB_RA:            8.900d {+00h 35m 36s} (J2000),
                   9.057d {+00h 36m 14s} (current),
                   8.413d {+00h 33m 39s} (1950)
GRB_DEC:         -74.600d {-74d 35' 59"} (J2000),
                 -74.511d {-74d 30' 38"} (current),
                 -74.875d {-74d 52' 30"} (1950)
GRB_ERROR:       1.68 [deg radius, statistical only]
DATA_SIGNIF:     26.20 [sigma]
DATA_INTERVAL:   2.048 [sec]
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25161.51 SOD {06:59:21.51} UT
GRB_PHI:         154.00 [deg]
GRB_THETA:         9.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 44"}
SUN_DIST:         76.57 [deg]   Sun_angle= -0.3 [hr] (East of Sun)
MOON_POSTN:      203.68d {+13h 34m 43s}   -6.77d {-06d 46' 05"}
MOON_DIST:        98.22 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      304.36,-42.48 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      307.19,-64.27 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160325291/quicklook/glg_lc_medres34_bn160325291.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_480581965.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~4 min after the notice.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:00:52 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      2
TRIGGER_NUM:     480581965
GRB_RA:           16.000d {+01h 04m 00s} (J2000),
                  16.121d {+01h 04m 29s} (current),
                  15.626d {+01h 02m 30s} (1950)
GRB_DEC:         -73.960d {-73d 57' 35"} (J2000),
                 -73.873d {-73d 52' 22"} (current),
                 -74.228d {-74d 13' 39"} (1950)
GRB_ERROR:       1.00 [deg radius, statistical only]
DATA_SIGNIF:     48.30 [sigma]
DATA_INTERVAL:   11.264 [sec]
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25161.51 SOD {06:59:21.51} UT
GRB_PHI:         166.00 [deg]
GRB_THETA:         8.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 45"}
SUN_DIST:         76.21 [deg]   Sun_angle= -0.8 [hr] (East of Sun)
MOON_POSTN:      203.69d {+13h 34m 45s}   -6.77d {-06d 46' 13"}
MOON_DIST:        99.22 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.74,-43.14 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      310.37,-65.79 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160325291/quicklook/glg_lc_medres34_bn160325291.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_480581965.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This is likely a Long GRB.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~4 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(42.0<100sec) coincident with the SWIFT_BAT event (trignum=680436).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:01:41 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.6467d {+01h 02m 35.20s} (J2000),
                  15.7763d {+01h 03m 06.31s} (current),
                  15.2462d {+01h 00m 59.08s} (1950)
GRB_DEC:         -72.6970d {-72d 41' 49.2"} (J2000),
                 -72.6100d {-72d 36' 36.0"} (current),
                 -72.9653d {-72d 57' 55.2"} (1950)
GRB_ERROR:       4.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       4.15e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.22 [sigma]
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25270.01 SOD {07:01:10.01} UT,   66.4 [sec] since BAT Trigger Time
TAM[0-3]:        327.66 237.21 261.58 243.55
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 46"}
SUN_DIST:         74.96 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.69d {+13h 34m 47s}   -6.77d {-06d 46' 20"}
MOON_DIST:       100.45 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.77,-44.41 [deg] galactic lon,lat of the burst
ECL_COORDS:      313.09,-65.21 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.05 arcmin from the BAT position.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:01:51 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.6467d {+01h 02m 35.2s} (J2000),
                  15.7763d {+01h 03m 06.3s} (current),
                  15.2462d {+01h 00m 59.0s} (1950)
GRB_DEC:         -72.6970d {-72d 41' 49.2"} (J2000),
                 -72.6100d {-72d 36' 36.0"} (current),
                 -72.9653d {-72d 57' 55.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       126 [cnts]
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25270.01 SOD {07:01:10.01} UT,   66.4 [sec] since BAT Trigger Time
CENTROID_X:      322.51,  raw= 323  [pixels]
CENTROID_Y:      276.61,  raw= 277  [pixels]
ROLL:            348.69 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -49.93
GRB_POS_XRT_Z:   40.59
IMAGE_URL:       sw00680436000msxps_rw.img
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 46"}
SUN_DIST:         74.96 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.70d {+13h 34m 47s}   -6.77d {-06d 46' 22"}
MOON_DIST:       100.45 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.77,-44.41 [deg] galactic lon,lat of the burst
ECL_COORDS:      313.09,-65.21 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:01:57 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.6467d {+01h 02m 35.2s} (J2000),
                  15.7763d {+01h 03m 06.3s} (current),
                  15.2462d {+01h 00m 59.0s} (1950)
GRB_DEC:         -72.6970d {-72d 41' 49.2"} (J2000),
                 -72.6100d {-72d 36' 36.0"} (current),
                 -72.9653d {-72d 57' 55.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       126 [cnts]
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25270.01 SOD {07:01:10.01} UT,   66.4 [sec] since BAT Trigger Time
CENTROID_X:      322.51,  raw= 323  [pixels]
CENTROID_Y:      276.61,  raw= 277  [pixels]
ROLL:            348.69 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -49.93
GRB_POS_XRT_Z:   40.59
IMAGE_URL:       sw00680436000msxps_rw.img
SUN_POSTN:         4.65d {+00h 18m 36s}   +2.01d {+02d 00' 46"}
SUN_DIST:         74.96 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.70d {+13h 34m 47s}   -6.77d {-06d 46' 23"}
MOON_DIST:       100.45 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.77,-44.41 [deg] galactic lon,lat of the burst
ECL_COORDS:      313.09,-65.21 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:03:47 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.597d {+01h 02m 23s} (J2000),
                  15.726d {+01h 02m 54s} (current),
                  15.195d {+01h 00m 47s} (1950)
GRB_DEC:         -72.706d {-72d 42' 22"} (J2000),
                 -72.619d {-72d 37' 08"} (current),
                 -72.975d {-72d 58' 28"} (1950)
GRB_DATE:        17472 TJD;    85 DOY;   16/03/25
GRB_TIME:        25203.61 SOD {07:00:03.61} UT
TRIGGER_INDEX:   124
GRB_PHI:           8.44 [deg]
GRB_THETA:        19.89 [deg]
DELTA_TIME:      -43.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     25.27 [sigma]
IMAGE_SIGNIF:    10.49 [sigma]
LC_URL:          sw00680436000msb.lc
SUN_POSTN:         4.65d {+00h 18m 37s}   +2.01d {+02d 00' 48"}
SUN_DIST:         74.96 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.71d {+13h 34m 51s}   -6.78d {-06d 46' 38"}
MOON_DIST:       100.44 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.40 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      313.05,-65.20 [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 = 32.35,-19.53 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:09:56 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.595d {+01h 02m 23s} (J2000)
POINT_DEC:       -72.689d {-72d 41' 18"} (J2000)
POINT_ROLL:      348.683d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25278.60 SOD {07:01:18.60} UT,   75.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        6.826
N_STARS:         190
X_OFFSET:        360 [pixels]
Y_OFFSET:        616 [pixels]
X_MAX:           1319 [pixels]
Y_MAX:           1575 [pixels]
DET_THRESH:      22
PHOTO_THRESH:    14
SL_URL:          sw00680436000msufc0074.fits
SUN_POSTN:         4.66d {+00h 18m 37s}   +2.02d {+02d 00' 54"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.76d {+13h 35m 02s}   -6.79d {-06d 47' 32"}
MOON_DIST:       100.44 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.20 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:10:27 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.595d {+01h 02m 23s} (J2000)
POINT_DEC:       -72.689d {-72d 41' 18"} (J2000)
POINT_ROLL:      348.683d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25278.60 SOD {07:01:18.60} UT,   75.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        6.826
N_STARS:         190
X_OFFSET:        360 [pixels]
Y_OFFSET:        616 [pixels]
X_MAX:           1319 [pixels]
Y_MAX:           1575 [pixels]
DET_THRESH:      22
PHOTO_THRESH:    14
SL_URL:          sw00680436000msufc0074.fits
SUN_POSTN:         4.66d {+00h 18m 38s}   +2.02d {+02d 00' 55"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.76d {+13h 35m 03s}   -6.79d {-06d 47' 36"}
MOON_DIST:       100.43 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.20 [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:     Fri 25 Mar 16 07:11:44 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.595d {+01h 02m 23s} (J2000)
POINT_DEC:       -72.689d {-72d 41' 18"} (J2000)
ROLL:            348.683d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25278.60 SOD {07:01:18.60} UT,   75.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     480582094
X_OFFSET:        776 [pixels]
Y_OFFSET:        1013 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       936
Y_GRB_POS:       1173
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0091.fits
SUN_POSTN:         4.66d {+00h 18m 38s}   +2.02d {+02d 00' 56"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.77d {+13h 35m 06s}   -6.80d {-06d 47' 47"}
MOON_DIST:       100.43 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.20 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:12:02 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.595d {+01h 02m 23s} (J2000)
POINT_DEC:       -72.689d {-72d 41' 18"} (J2000)
ROLL:            348.683d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25278.60 SOD {07:01:18.60} UT,   75.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     480582094
X_OFFSET:        776 [pixels]
Y_OFFSET:        1013 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       936
Y_GRB_POS:       1173
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0091.fits
SUN_POSTN:         4.66d {+00h 18m 38s}   +2.02d {+02d 00' 56"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.78d {+13h 35m 06s}   -6.80d {-06d 47' 50"}
MOON_DIST:       100.43 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.79,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.20 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:16:53 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
POINT_ROLL:      348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25491.40 SOD {07:04:51.40} UT,   287.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        3.077
N_STARS:         190
X_OFFSET:        456 [pixels]
Y_OFFSET:        693 [pixels]
X_MAX:           1415 [pixels]
Y_MAX:           1652 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    8
SL_URL:          sw00680436000msufc0287.fits
SUN_POSTN:         4.66d {+00h 18m 39s}   +2.02d {+02d 01' 01"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.81d {+13h 35m 16s}   -6.81d {-06d 48' 32"}
MOON_DIST:       100.42 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:17:19 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
POINT_ROLL:      348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25491.40 SOD {07:04:51.40} UT,   287.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        3.077
N_STARS:         190
X_OFFSET:        456 [pixels]
Y_OFFSET:        693 [pixels]
X_MAX:           1415 [pixels]
Y_MAX:           1652 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    8
SL_URL:          sw00680436000msufc0287.fits
SUN_POSTN:         4.66d {+00h 18m 39s}   +2.02d {+02d 01' 01"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.82d {+13h 35m 16s}   -6.81d {-06d 48' 36"}
MOON_DIST:       100.42 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [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:     Fri 25 Mar 16 07:18:31 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
ROLL:            348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25491.40 SOD {07:04:51.40} UT,   287.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     480582307
X_OFFSET:        776 [pixels]
Y_OFFSET:        1013 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       936
Y_GRB_POS:       1173
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0304.fits
SUN_POSTN:         4.66d {+00h 18m 39s}   +2.02d {+02d 01' 03"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.83d {+13h 35m 19s}   -6.81d {-06d 48' 46"}
MOON_DIST:       100.41 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:18:51 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
ROLL:            348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25491.40 SOD {07:04:51.40} UT,   287.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     480582307
X_OFFSET:        776 [pixels]
Y_OFFSET:        1013 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       936
Y_GRB_POS:       1173
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0304.fits
SUN_POSTN:         4.66d {+00h 18m 39s}   +2.02d {+02d 01' 03"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.83d {+13h 35m 19s}   -6.81d {-06d 48' 49"}
MOON_DIST:       100.41 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:22:57 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
POINT_ROLL:      348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  26068.55 SOD {07:14:28.55} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.668
N_STARS:         190
X_OFFSET:        216 [pixels]
Y_OFFSET:        453 [pixels]
X_MAX:           1655 [pixels]
Y_MAX:           1892 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00680436000msufc0864.fits
SUN_POSTN:         4.66d {+00h 18m 39s}   +2.02d {+02d 01' 07"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.86d {+13h 35m 27s}   -6.82d {-06d 49' 24"}
MOON_DIST:       100.40 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:23:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
POINT_ROLL:      348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  26068.55 SOD {07:14:28.55} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.668
N_STARS:         190
X_OFFSET:        216 [pixels]
Y_OFFSET:        453 [pixels]
X_MAX:           1655 [pixels]
Y_MAX:           1892 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00680436000msufc0864.fits
SUN_POSTN:         4.66d {+00h 18m 40s}   +2.02d {+02d 01' 08"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.87d {+13h 35m 28s}   -6.83d {-06d 49' 29"}
MOON_DIST:       100.40 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [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:     Fri 25 Mar 16 07:24:43 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
ROLL:            348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  26068.55 SOD {07:14:28.55} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     480582884
X_OFFSET:        775 [pixels]
Y_OFFSET:        1012 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       935
Y_GRB_POS:       1172
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0881.fits
SUN_POSTN:         4.67d {+00h 18m 40s}   +2.02d {+02d 01' 09"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.88d {+13h 35m 30s}   -6.83d {-06d 49' 40"}
MOON_DIST:       100.40 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [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:     Fri 25 Mar 16 07:24:58 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     680436,   Seg_Num: 0
POINT_RA:         15.587d {+01h 02m 21s} (J2000)
POINT_DEC:       -72.688d {-72d 41' 17"} (J2000)
ROLL:            348.692d
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  26068.55 SOD {07:14:28.55} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     480582884
X_OFFSET:        775 [pixels]
Y_OFFSET:        1012 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       935
Y_GRB_POS:       1172
BINNING_INDEX:   1
IM_URL:          sw00680436000msuni0881.fits
SUN_POSTN:         4.67d {+00h 18m 40s}   +2.02d {+02d 01' 09"}
SUN_DIST:         74.95 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      203.88d {+13h 35m 31s}   -6.83d {-06d 49' 42"}
MOON_DIST:       100.39 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.80,-44.42 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      313.09,-65.19 [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 #19222
E. Sonbas (Adiyaman Univ.), A. Y. Lien (GSFC/UMBC) and K. L. Page (U Leicester) report on behalf of the Swift Team:
At 07:00:03 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160325A (trigger=680436). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 15.597, -72.706 which is
```
   RA(J2000) = 01h 02m 23s
   Dec(J2000) = -72d 42' 22"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 80 sec. One of the major pulses occurred at ~ -40 s before BAT trigger during spacecraft slews. The peak count rate was ~9000 counts/sec (15-350 keV), at ~3 sec after the trigger.
The XRT began observing the field at 07:01:10.0 UT, 66.4 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 15.65210, -72.69671 which is equivalent to:
```
   RA(J2000)  = 01h 02m 36.50s
   Dec(J2000) = -72d 41' 48.2"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 67 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 (5.91 x 10^21 cm^-2, Willingale et al. 2013), with an excess column of 2.3 (+2.60/-2.22) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 4.15e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 74 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. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the sub-image. The 8'x8' region for the list of sources generated on-board covers 0.00% of the XRT error circle. No correction has been made for the expected extinction corresponding to E(B-V) of 0.04.
Burst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 25 Mar 16 07:41:48 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     680436,   Seg_Num: 0
GRB_RA:           15.6523d {+01h 02m 36.55s} (J2000),
                  15.7819d {+01h 03m 07.65s} (current),
                  15.2519d {+01h 01m 00.44s} (1950)
GRB_DEC:         -72.6965d {-72d 41' 47.4"} (J2000),
                 -72.6095d {-72d 36' 34.2"} (current),
                 -72.9648d {-72d 57' 53.4"} (1950)
GRB_ERROR:       3.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17472 TJD;    85 DOY;   16/03/25
IMG_START_TIME:  25714.00 SOD {07:08:34.00} UT,   510.4 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:         4.68d {+00h 18m 42s}   +2.02d {+02d 01' 25"}
SUN_DIST:         74.97 [deg]   Sun_angle= -0.7 [hr] (East of Sun)
MOON_POSTN:      204.01d {+13h 36m 03s}   -6.87d {-06d 52' 07"}
MOON_DIST:       100.34 [deg]
MOON_ILLUM:      97 [%]
GAL_COORDS:      301.77,-44.41 [deg] galactic lon,lat of the burst
ECL_COORDS:      313.09,-65.21 [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:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN Circular #19223
D. Fugazza, A. Melandri (INAF/OAB) report on behalf of the REM team:
We observed the field of GRB 160325A (Sonbas et al., GCN 19222) with the 60-cm robotic telescope REM located at the La Silla Observatory (Chile). The observations started at 07:01:08 UT, 65 seconds after the Burst, and were carried out simultaneously with in the g, r, i, z and H bands. An uncatalogued bright source in the XRT error box is detected at the coordinates:
RA(2000) = 01:02:36.06 Dec(2000) = -72:41:47.7
with an estimated uncertainty of +/- 0.7 arcsec. A very preliminary photometry indicates it was H ~10.71 +/- 0.01 about 270 sec after the burst.
Further observations are in progress to assess its variability.
GCN Circular #19224
O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:
"At 06:59:21.51 UT on the 25th of March 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160325A (trigger 480581965 / 160325291), which was also detected by Swift (Sonbas et al. 2008, GCN 19222). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time using the Swift XRT position is about 6 degrees.
The GBM light curve consists of two main emission episodes with a duration (T90) of about 43 s (50-300 keV). The time-averaged spectrum from T0+2.3 s to T0+45.3 s is well fit by a Band function with Epeak = 235 +/- 19 keV, alpha = -0.78 +/- 0.05, and beta = -2.21 +/- 0.14.
The event fluence (10-1000 keV) in this time interval is (1.91 +/- 0.04) E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+9.5 s in the 10-1000 keV band is 8.5 +/- 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 #19227
M. Axelsson (KTH Stockholm), E. Bissaldi (Politecnico and INFN Bari), R. Desiante (INFN Torino and Udine University) and F. Longo (University of Trieste and INFN Trieste) report on behalf of the Fermi-LAT team:
At UT 06:59:21 on March 25 2016 Fermi-LAT detected high-energy emission from GRB 160325A, which was also detected by Swift (Sonbas et al. 2016, GCN 19222) and Fermi-GBM (trigger 480581965/160325291; Roberts 2016, GCN 19224).
The best LAT on-ground location is found to be: RA, Dec (J2000) = (16.14, -72.66) with an error radius of 0.17 deg (90 % containment, statistical error only).
The Fermi-LAT position is consistent with that found by Swift-XRT (Sonbas et al. 2016, GCN 19222).
The LAT data show a significant increase in the event rate that is spatially and temporally correlated with the trigger with high significance. More than 45 photons >100 MeV and 3 photons > 1GeV are detected in the 1500 s following the trigger. The highest-energy photon is a 3 GeV event which is observed 100 seconds after the GBM trigger.
The Fermi-LAT point of contact for this burst is M. Axelsson (magaxe@kth.se).
The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
GCN Circular #19228
L. M. McCauley (PSU) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team:
UVOT took a finding chart exposure of 150 seconds with the White filter starting 74 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =        01:02:36.28 =  15.65118
  DEC(J2000) = -72:41:46.8  = -72.69634
```
with a 90%-confidence error radius of about 0.61 arc sec. This position is 5.35 arc sec. from the center of the XRT error circle and consistent with the position reported by Fugazza et al. (GCN Circ. 19223).
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white_fc              74          160          86           15.48+-0.03
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.04 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19229
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 2264 s of XRT Photon Counting mode data and 3 UVOT images for GRB 160325A, 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 = 15.65055, -72.69659 which is equivalent to:
```
RA (J2000): 01h 02m 36.13s
Dec (J2000): -72d 41' 47.7"
```
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 #19230
A. Melandri, D. Fugazza (INAF-OAB), M. De Pasquale (MSSL-UCL) report on behalf of a larger collaboration:
Further analysis of REM near-infrared observations of the field of of GRB 160325A (Sonbas et al., GCN 19222) showed that the source reported as candidate afterglow in our earlier imaging (Fugazza & Melandri, GCN 19223; McCauley & Sonbas, GCN 19228) has faded in the JHK filters. Observations cover the time interval bewteen ~1 and 120 minutes after the burst event.
The light curve has an initial decay of alpha1 ~ 0.45, and after 10 minutes it steepens to alpha2 ~ 1.5. The fading nature confirms that this source is the afterglow of GRB 160325A.

GCN Circular #19231
L. M. Z. Hagen (PSU) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team:
We report further on the Swift/UVOT observations of GRB 160325A which began 75 s after the BAT trigger (Sonbas et al., GCN Circ. 19222). A source was reported earlier by McCauley et al. (GCN Circ. 19228), which was consistent with the XRT position (Evans et al., GCN Circ. 19229) and infrared detection (Fugazza et al., GCN Circ. 19223). We confirm that the source is rapidly fading.
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white               75          224          146         15.65+-0.05
white              567         1187          205         17.24+-0.05
white             7227        12203          231         19.59+-0.16
v                  617          809           38         15.12+-0.07
v                 1044         1237           38         15.79+-0.10
v                 1392         6402          216         17.73+-0.14
b                  543          735           38         17.11+-0.11
b                 1143         1510           58         18.70+-0.33
b                 7023         7222          196        >19.64
u                  287          537          245         18.91+-0.22
u                  691         7017          274        >19.47
uvw1               666         1461           97         18.36+-0.32
uvw1              6613         6812          196         19.05+-0.33
uvm2               641         1263           77         18.30+-0.34
uvm2              1416         6607          216         18.73+-0.29
uvw2               593         1387           97        >18.63
uvw2              5998         6197          196         18.30+-0.19

The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.04 in the direction of the burst (Schlegel et al. 1998).

GCN Circular #19232
A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), V. D'Elia (ASDC) and E. Sonbas report on behalf of the Swift-XRT team:
We have analysed 7.5 ks of XRT data for GRB 160325A (Sonbas et al. GCN Circ. 19222), from 55 s to 41.2 ks after the BAT trigger. The data comprise 436 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. 19229).
The late-time light curve (from T0+6.0 ks) can be modelled with a power-law decay with a decay index of alpha=2.7 (+0.6, -0.5).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.342 (+0.033, -0.029). The best-fitting absorption column is consistent with the Galactic value of 5.9 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.18 (+0.16, -0.08) and a best-fitting absorption column consistent with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.9 x 10^-11 (7.3 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     5.9 (+0.9, -0.0) x 10^21 cm^-2
Galactic foreground: 5.9 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:	     2.18 (+0.16, -0.08)
```
If the light curve continues to decay with a power-law decay index of 2.7, the count rate at T+24 hours will be 1.5 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.9 x 10^-15 (1.1 x 10^-14) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00680436.
This circular is an official product of the Swift-XRT team.
GCN Circular #19233
C. Delvaux (MPE Garching), D. A. Kann (TLS Tautenburg), F. Knust, and J. Greiner (both MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 160325A (Swift trigger 680436; Sonbas et al., GCN #19222, Fermi GBM detection, Roberts, GCN #19924, Fermi LAT detection, Axelsson et al., GCN #19227) 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 23:29 UT on 25/03/2016, 16.5 hrs after the GRB trigger. They were performed at an average seeing of 1.7" and at an average airmass of 2.3.
We do not detect the source reported by Fugazza et Melandri (GCN #19223) down to the following magnitudes (in AB system):
```
g > 22.4 mag,
r > 22.5 mag,
i > 22.3 mag,
z > 22.4 mag,
J > 20.3 mag,
H > 19.8 mag, and
K > 18.5 mag.
```
Given upper limits are calibrated against GROND zeropoints as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.1 mag in the direction of the burst (Schlafly & Finkbeiner 2011).
GCN Circular #19234
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), E. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160325A (trigger #680436) (Sonbas et al., GCN Circ. 19222). The BAT ground-calculated position is RA, Dec = 15.697, -72.702 deg which is
```
  RA(J2000)  =  01h 02m 47.4s
  Dec(J2000) = -72d 42' 06.4"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%.
The mask-weighted light curve shows a multi-peaked structure that starts at ~ T-60 s and ends at ~T+60 s. The burst location came into the BAT FoV at ~T-93 s during a preplanned slew, so there could be further burst activities beforehand. The burst structure contains two main pulses. The first pulse starts at ~T-60 s, peaks at ~ T-34 s, and ends at ~T-25 s. The second pulse starts at ~T0, peaks at ~T+3 s, and ends ~T+5 s. T90 (15-350 keV) is 64.9 +- 14.7 sec (estimated error including systematics).
The time-averaged spectrum from T-51.74 to T+60.45 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.27 +- 0.04. The fluence in the 15-150 keV band is 7.1 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T-33.46 sec in the 15-150 keV band is 5.2 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/680436/BA/
GCN Circular #19244
A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline on behalf of the Konus-Wind team, report:
The long-duration GRB 160325A (Swift-BAT trigger #680436: Sonbas, Lien & Page, GCN 19222; Fermi GBM detection: Roberts, GCN 19224; Fermi-LAT detection: Axelsson et al., GCN 19227) triggered Konus-Wind at T0=25162.835 s UT (06:59:22.835).
The burst light curve shows two emission episodes, a total duration of the burst (80-360 keV) is ~45 s. The emission is seen up to ~1.5 MeV.
As observed by Konus-Wind, the burst had a fluence of 1.73(-0.12,+0.14)x10^-5 erg/cm2, and a 64-ms peak energy flux, measured from T0+10.304 s, of 3.04(-1.04,+1.08)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst (measured from T0 to T0+49.408 s) is best fit in the 20 keV - 1.5 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.93(-0.14,+0.15), and Ep = 214(-23,+31) keV (chi2 = 69/60 dof). Fitting by the GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.45 (chi2 = 69/59 dof).
The spectrum near the peak count rate (measured from T0 to T0+16.640 s) is best fit in the 20 keV - 2 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.76(-0.15,+0.18), the high energy photon index beta = -2.47(-0.59,+0.26), the peak energy Ep = 207(-26,+32) keV, chi2 = 70/57 dof.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB160325_T25162/
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.

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Jochen Greiner, last update: 29-Mar-2016 [Disclaimer]