Gamma-ray Burst 140515A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:13:07 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     599037,   Seg_Num: 0
GRB_RA:          186.036d {+12h 24m 09s} (J2000),
                 186.218d {+12h 24m 52s} (current),
                 185.403d {+12h 21m 37s} (1950)
GRB_DEC:         +15.077d {+15d 04' 38"} (J2000),
                 +14.998d {+14d 59' 52"} (current),
                 +15.354d {+15d 21' 15"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4222 [cnts]    Image_Peak=212 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   137     E_range: 15-50 keV
BKG_INTEN:       26280 [cnts]
BKG_TIME:        33139.98 SOD {09:12:19.98} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16792 TJD;   135 DOY;   14/05/15
GRB_TIME:        33156.69 SOD {09:12:36.69} UT
GRB_PHI:         156.72 [deg]
GRB_THETA:        13.16 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     13.89 [sigma]
IMAGE_SIGNIF:    8.23 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +1  -1  +0  +0 +55  +0 
SUN_POSTN:        52.11d {+03h 28m 26s}  +18.89d {+18d 53' 13"}
SUN_DIST:        123.53 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.64d {+16h 02m 33s}  -17.81d {-17d 48' 19"}
MOON_DIST:        62.87 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.78, 76.38 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      179.38, 16.20 [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 = 122.53,15.88 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:14:05 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.032d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.081d {+15d 04' 51"} (J2000)
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33232.49 SOD {09:13:52.49} UT,   75.8 [sec] since BAT Trigger Time
COUNTS:          3    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:     Thu 15 May 14 09:17:07 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     599037,   Seg_Num: 0
GRB_RA:          186.036d {+12h 24m 09s} (J2000),
                 186.218d {+12h 24m 52s} (current),
                 185.403d {+12h 21m 37s} (1950)
GRB_DEC:         +15.077d {+15d 04' 38"} (J2000),
                 +14.998d {+14d 59' 52"} (current),
                 +15.354d {+15d 21' 15"} (1950)
GRB_DATE:        16792 TJD;   135 DOY;   14/05/15
GRB_TIME:        33156.69 SOD {09:12:36.69} UT
TRIGGER_INDEX:   137
GRB_PHI:         156.72 [deg]
GRB_THETA:        13.16 [deg]
DELTA_TIME:      -69.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     13.89 [sigma]
IMAGE_SIGNIF:    8.23 [sigma]
LC_URL:          sw00599037000msb.lc
SUN_POSTN:        52.11d {+03h 28m 27s}  +18.89d {+18d 53' 15"}
SUN_DIST:        123.53 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.68d {+16h 02m 43s}  -17.81d {-17d 48' 36"}
MOON_DIST:        62.91 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.78, 76.38 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      179.38, 16.20 [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 = 122.53,15.88 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:18:16 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.032d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.081d {+15d 04' 52"} (J2000)
POINT_ROLL:      305.326d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33235.93 SOD {09:13:55.93} UT,   79.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.341
N_STARS:         10
X_OFFSET:        437 [pixels]
Y_OFFSET:        549 [pixels]
X_MAX:           1396 [pixels]
Y_MAX:           1508 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00599037000msufc0079.fits
SUN_POSTN:        52.11d {+03h 28m 27s}  +18.89d {+18d 53' 16"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.69d {+16h 02m 45s}  -17.81d {-17d 48' 41"}
MOON_DIST:        62.92 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:20:23 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.032d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.081d {+15d 04' 52"} (J2000)
POINT_ROLL:      305.326d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33235.93 SOD {09:13:55.93} UT,   79.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.341
N_STARS:         10
X_OFFSET:        437 [pixels]
Y_OFFSET:        549 [pixels]
X_MAX:           1396 [pixels]
Y_MAX:           1508 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00599037000msufc0079.fits
SUN_POSTN:        52.11d {+03h 28m 27s}  +18.89d {+18d 53' 17"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.71d {+16h 02m 51s}  -17.81d {-17d 48' 50"}
MOON_DIST:        62.94 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:     Thu 15 May 14 09:21:27 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     599037,   Seg_Num: 0
GRB_RA:          186.0648d {+12h 24m 15.55s} (J2000),
                 186.2466d {+12h 24m 59.18s} (current),
                 185.4319d {+12h 21m 43.65s} (1950)
GRB_DEC:         +15.1041d {+15d 06' 14.7"} (J2000),
                 +15.0246d {+15d 01' 28.4"} (current),
                 +15.3811d {+15d 22' 51.9"} (1950)
GRB_ERROR:       3.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33252.00 SOD {09:14:12.00} UT,   95.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        52.12d {+03h 28m 28s}  +18.89d {+18d 53' 17"}
SUN_DIST:        123.53 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.72d {+16h 02m 53s}  -17.82d {-17d 48' 55"}
MOON_DIST:        62.94 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.83, 76.42 [deg] galactic lon,lat of the burst
ECL_COORDS:      179.40, 16.24 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 1.1% < P(seren) < 2.8%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:24:12 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
POINT_ROLL:      305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33449.37 SOD {09:17:29.37} UT,   292.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.640
N_STARS:         18
X_OFFSET:        197 [pixels]
Y_OFFSET:        309 [pixels]
X_MAX:           1636 [pixels]
Y_MAX:           1748 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00599037000msufc0292.fits
SUN_POSTN:        52.12d {+03h 28m 28s}  +18.89d {+18d 53' 19"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.75d {+16h 03m 00s}  -17.82d {-17d 49' 06"}
MOON_DIST:        62.98 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:25:30 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
ROLL:            305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33449.37 SOD {09:17:29.37} UT,   292.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     421838261
X_OFFSET:        756 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       916
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00599037000msuni0305.fits
SUN_POSTN:        52.12d {+03h 28m 28s}  +18.89d {+18d 53' 20"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.76d {+16h 03m 03s}  -17.82d {-17d 49' 12"}
MOON_DIST:        62.99 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:25:22 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
ROLL:            305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33449.37 SOD {09:17:29.37} UT,   292.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     421838261
X_OFFSET:        756 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       916
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00599037000msuni0305.fits
SUN_POSTN:        52.12d {+03h 28m 28s}  +18.89d {+18d 53' 20"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.76d {+16h 03m 03s}  -17.82d {-17d 49' 11"}
MOON_DIST:        62.99 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:     Thu 15 May 14 09:24:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
POINT_ROLL:      305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33449.37 SOD {09:17:29.37} UT,   292.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.640
N_STARS:         18
X_OFFSET:        197 [pixels]
Y_OFFSET:        309 [pixels]
X_MAX:           1636 [pixels]
Y_MAX:           1748 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00599037000msufc0292.fits
SUN_POSTN:        52.12d {+03h 28m 28s}  +18.89d {+18d 53' 19"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.75d {+16h 03m 00s}  -17.82d {-17d 49' 06"}
MOON_DIST:        62.98 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:     Thu 15 May 14 09:28:42 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     599037,   Seg_Num: 0
GRB_RA:          186.0638d {+12h 24m 15.31s} (J2000),
                 186.2456d {+12h 24m 58.94s} (current),
                 185.4309d {+12h 21m 43.41s} (1950)
GRB_DEC:         +15.1043d {+15d 06' 15.4"} (J2000),
                 +15.0248d {+15d 01' 29.1"} (current),
                 +15.3813d {+15d 22' 52.6"} (1950)
GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  33252.00 SOD {09:14:12.00} UT,   95.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        52.12d {+03h 28m 29s}  +18.89d {+18d 53' 22"}
SUN_DIST:        123.52 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.80d {+16h 03m 11s}  -17.82d {-17d 49' 25"}
MOON_DIST:        63.00 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.83, 76.42 [deg] galactic lon,lat of the burst
ECL_COORDS:      179.40, 16.24 [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 1.1% < P(seren) < 2.8%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:30:16 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
POINT_ROLL:      305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  34026.58 SOD {09:27:06.58} UT,   869.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.209
N_STARS:         44
X_OFFSET:        197 [pixels]
Y_OFFSET:        309 [pixels]
X_MAX:           1636 [pixels]
Y_MAX:           1748 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00599037000msufc0869.fits
SUN_POSTN:        52.12d {+03h 28m 29s}  +18.89d {+18d 53' 23"}
SUN_DIST:        123.51 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.81d {+16h 03m 15s}  -17.83d {-17d 49' 32"}
MOON_DIST:        63.03 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 15 May 14 09:30:30 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
POINT_ROLL:      305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  34026.58 SOD {09:27:06.58} UT,   869.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.209
N_STARS:         44
X_OFFSET:        197 [pixels]
Y_OFFSET:        309 [pixels]
X_MAX:           1636 [pixels]
Y_MAX:           1748 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00599037000msufc0869.fits
SUN_POSTN:        52.12d {+03h 28m 29s}  +18.89d {+18d 53' 23"}
SUN_DIST:        123.51 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.81d {+16h 03m 15s}  -17.83d {-17d 49' 33"}
MOON_DIST:        63.03 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:     Thu 15 May 14 09:31:41 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
ROLL:            305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  34026.58 SOD {09:27:06.58} UT,   869.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     421838838
X_OFFSET:        756 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       916
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00599037000msuni0882.fits
SUN_POSTN:        52.12d {+03h 28m 29s}  +18.89d {+18d 53' 23"}
SUN_DIST:        123.51 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.83d {+16h 03m 18s}  -17.83d {-17d 49' 38"}
MOON_DIST:        63.04 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:     Thu 15 May 14 09:31:53 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     599037,   Seg_Num: 0
POINT_RA:        186.035d {+12h 24m 08s} (J2000)
POINT_DEC:       +15.082d {+15d 04' 57"} (J2000)
ROLL:            305.330d
IMG_START_DATE:  16792 TJD;   135 DOY;   14/05/15
IMG_START_TIME:  34026.58 SOD {09:27:06.58} UT,   869.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     421838838
X_OFFSET:        756 [pixels]
Y_OFFSET:        868 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       916
Y_GRB_POS:       1028
BINNING_INDEX:   1
IM_URL:          sw00599037000msuni0882.fits
SUN_POSTN:        52.12d {+03h 28m 29s}  +18.89d {+18d 53' 24"}
SUN_DIST:        123.51 [deg]   Sun_angle= -8.9 [hr] (East of Sun)
MOON_POSTN:      240.83d {+16h 03m 19s}  -17.83d {-17d 49' 38"}
MOON_DIST:        63.05 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      273.76, 76.38 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      179.38, 16.21 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #16267
P. D'Avanzo (INAF-OAB), M. G. Bernardini (INAF-OAB), V. D'Elia (ASDC), P. A. Evans (U Leicester), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 09:12:36 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 140515A (trigger=599037). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 186.036, +15.077 which is
```
   RA(J2000) = 12h 24m 09s
   Dec(J2000) = +15d 04' 38"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a double-peaked structure with a duration of about 30 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 09:13:52.4 UT, 75.8 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 186.0639, 15.1045 which is equivalent to:
```
   RA(J2000)  = 12h 24m 15.35s
   Dec(J2000) = +15d 06' 16.4"
```
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This location is 138 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 2.54 x 10^20 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 79 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 none of the XRT error circle. 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 0.02.
Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo 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 #16269
R. Chornock (Harvard), D. B. Fox (Penn State), and E. Berger (Harvard) report:
We observed the field of GRB 140515A (D'Avanzo et al., GCN 16267) using GMOS on the Gemini-N 8-m telescope, starting at 10:48 UT on 15 May. A faint source was present in the i band acquisition image at a position consistent with the X-ray afterglow. We obtained 2x900s of spectroscopy of this likely afterglow, covering the wavelength range 5900-10150 Angstroms at a resolution of R~1200. The afterglow has a strong continuum at long wavelengths that sharply drops to near zero at wavelengths shortward of lambda~8900 Angs, consistent with the onset of Lyman-alpha absorption at z=6.32. Isolated wavelength intervals of IGM transmission exist between 7500 and 8000 Angs (corresponding to z~5.2-5.6 relative to Ly-alpha). Further analysis is ongoing.
We acknowledge excellent support from Gemini observer Lucas Fuhrman.
GCN Circular #16270
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 2066 s of XRT Photon Counting mode data and 2 UVOT images for GRB 140515A, 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 = 186.06452, +15.10491 which is equivalent to:
```
RA (J2000): 12h 24m 15.48s
Dec (J2000): +15d 06' 17.7"
```
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 #16271
H. Ohuchi, T. Yoshii, Y. Saito, Y. Tachibana, S. Kurita, Y. Ono, T. Fujiwara, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 140515A (P.D'Avanzo et al., GCN Circular #16267) with the optical three color (g, Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2014-05-15 10:32:10 UT ( 1.3h after the burst). We did not find any new point source within the enhanced XRT circle in all the three bands.The measured magnitudes were listed below.
```
T0+[sec]     MID-UT    T-EXP[sec]     g'            Rc          Ic
---------------------------------------------------------------------------------------------------------
 9301         11:47:37        9180         > 20.8    >20.5    >19.4
---------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst 
T-EXP: Total Exposure time 
```
We used GSC2.3 catalog for flux calibration.
GCN Circular #16273
S. R. Oates (IAA-CSIC,UCL-MSSL) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 140515A 79 s after the BAT trigger (D'Avanzo et al., GCN Circ. 16267). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 16270) is detected in the initial UVOT exposures. The lack of detection in all UVOT filters is consistent with a redshift of 6.32 (Chornock et al., GCN Circ. 16269).
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            79          229          147         >20.7
u_FC               293          542          246         >20.0
white               79         7407          638         >21.5
v                  628         7818          471         >19.7
b                  548         7202          456         >20.6
u                  293        13671          1398        >20.9
w1                1618        12925          1140        >20.9
m2                6387        12019          1082        >20.6
w2                5977         7612          393         >20.5
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #16274
W. Fong (Harvard), R. Chornock (Harvard), D. Fox (PSU), and E. Berger (Harvard) report:
"We observed the location of the long-duration GRB 140515A (D'Avanzo et al., GCN 16267) with the Gemini Multi-Object Spectrograph (GMOS) mounted on the Gemini-North 8-meter telescope at a mid-time of 2014 May 15.458 UT (1.78 hr after the BAT trigger). We obtained 480 sec in each of the i- and z-bands in 0.45" seeing. We detect the optical afterglow (Chornock et al., GCN 16269), within the enhanced XRT position (Goad et al., GCN 16270), located at
```
RA(J2000) = 12:24:15.51
Dec(J2000) = +15:06:16.6
```
with a positional uncertainty of 0.1" in each coordinate. The optical afterglow has a brightness of z = 20.27 +/- 0.11 AB mag, and is at least 3 mag fainter in our i-band observations. Both the astrometry and photometry are calibrated to SDSS.
We thank the Gemini staff for their assistance with these observations."
GCN Circular #16275
WeiKang Zheng, Alexei V. Filippenko, Adam Morgan (UC Berkeley), and S. B. Cenko (NASA/Goddard Space Flight Center) report on behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to Swift GRB 140515A (D'Avanzo et al., GCN 16267) starting at 09:14:22 UT, 106 s after the burst. Observations were performed with an automatic sequence in the clear (roughly R), V and I filters, and the exposure time was 20 s per image. We do not detect the optical afterglow (Chornock et al., GCN 16269; Sahu, GCN 16272; Fong et al., GCN 16274) in our images within the enhanced XRT error circle (Goad et al., GCN 16270). The typical limiting magnitude of our single clear image is about 17.8, and about 17.1,16.9 mag for the V and I bands respectively.
GCN Circular #16277
P. D'Avanzo, M. G. Bernardini (INAF-OAB), P. A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
We have analysed 7.1 ks of XRT data for GRB 140515A (D'Avanzo et al. GCN Circ. 16267), from 60 s to 13.6 ks after the BAT trigger. The data comprise 9 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 16270).
The light curve can be modelled with a power-law decay with an initial decay index of alpha=2.5 (+0.5, -0.3). Then at T0+1100 s the light curve rises, reaching a count rate ~ 0.3 ct/sec. The remaining two orbits show irregular rate variations likely due to an underlying flaring activity, with a count rate ~ 0.3 ct/sec and ~ 0.1 ct/sec respectively.
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.75 (+0.12, -0.11). The best-fitting absorption column is 1.7 (+3.2, -1.7) x 10^22 cm^-2, at a redshift of 6.32 (Chornock et al., GCN Circ. 16269), in addition to the Galactic value of 2.5 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 (3.9 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Galactic foreground: 2.5 x 10^20 cm^-2
Intrinsic column:    1.7 (+3.2, -1.7) x 10^22 cm^-2 at z=6.32
Photon index:	     1.75 (+0.12, -0.11)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00599037.
This circular is an official product of the Swift-XRT team.
GCN Circular #16278
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), J. Gorosabel
(IAA-CSIC, UPV-EHU), D. Xu (DARK/NBI), J.P.U. Fynbo
(DARK/NBI), P. Jakobsson (U. Iceland), D. Malesani
(DARK/NBI), N.R. Tanvir (U. Leicester), E. Gafton
(OKC, Stockholm Univ.) and T. Libbrecht (Stockholm Univ.)
report on behalf of a larger collaboration:
We have observed the afterglow of GRB 140515A (D'Avanzo et al.,
GCN 16267) with the 2.5m NOT telescope. Observations consisted
of 5x300s imaging in the z-band and have an average epoch of
12.10 hr after the burst. The images reveal the optical afterglow
detected by Chornock et al. (GCN 16269) and Fong et al. (GCN
16274) at a magnitude of z(AB) = 22.15+/-0.15, as compared with
SDSS stars. This indicates a decay with a slope of alpha ~ -0.9
(where F_nu~t^alpha) as compared with the photometry of Fong
et al. (GCN 16274). Further observations are ongoing.
GCN Circular #16279
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), J. Gorosabel (IAA-CSIC, UPV-EHU), C.C. Thoene (IAA-CSIC), A. Cabrera-Lavers, D. Reverte and C. Alvarez (IAC-ULL) report on behalf of a larger collaboration:
We have obtained spectroscopic observations of the afterglow of GRB 140415A (D'Avanzo et al., GCN 16267; Chornock et al. GCN 16269; Fong et al. GCN 16274; de Ugarte Postigo et al. GCN 16278) using the 10.4m GTC telescope (+OSIRIS). Our observation started at 22:37 UT (13.41 hr after the burst), with a seeing of 0.6", and consisted of 3x1800s exposures using grism R2500I, which covers the range between 7330 and 10000 A at a resolution of ~2500.
In a preliminary reduction we detect a strong continuum above 8900 A, with no significant absorption features. The sharp decay below 8900 A is consistent with Ly-alpha absorption at the redshift of 6.32 suggested by Chornock et al. (GCN 16269). The transmission of the Ly-forest is low, but some emission is detected down to the blue limit of our spectrum.
GCN Circular #16280
J. Graham (MPE Garching), S. Schmidl (TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 140515A (Swift trigger 599037; D'Avanzo et al., GCN 16267) 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 22:53 UT on March 15, 2014, 13.7 hrs after the GRB trigger. They were performed at an average seeing of 0.9" and at an average airmass of 1.4.
We detect the afterglow reported by Chornock et al. (GCN 16269).
Based on a total exposure of 50 min in g'r'i'z' and 40 min in JHK, at a mid-time of 17.0 hrs after the burst, we measure the following preliminary magnitudes (in AB):
```
g' > 24.1 mag,
r' > 24.5 mag,
i' > 24.2 mag,
z' = 22.1 +/- 0.1 mag,
J  = 20.9 +/- 0.2 mag,
H  = 20.9 +/- 0.2 mag, and
K  > 19.1 mag.
```
Based on these data, the photometric redshift is z= 6.5 +/-0.2, which is consistent with the spectroscopic redshift reported by Chornock et al. (GCN 16269).
Given magnitudes are calibrated against SDSS (g'r'i'z') as well as 2MASS (JHK) field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.02 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular #16282
A. Melandri, P. D'Avanzo (INAF/OAB), A. Fiorenzano and G. Mainella (INAF/TNG) report on behalf of the CIBO collaboration:.
We observed the field of GRB 140515A (D'Avanzo et al., GCN 16267) using the NICS near-Infrared camera on the 3.6m TNG Telescope (La Palma, Canary Islands).
We obtained a series of imaging observations in the J and H bands for a total exposure time of 30 and 60 minutes respectively. The GRB afterglow is clearly detected in both bands at a level of
```
      Dt                Exposure    Filter      Mag (err)
[hr from GRB]      [min]        

    14.54	   60	         H	  19.35 (0.12)
    15.60	   30		 J	  19.52 (0.18)
```
Magnitudes are in the Vega system, calibrated against the 2MASS catalogue. We thank the TNG staff for the support.
GCN Circular #16283
T. Laskar, A. Zauderer, and E. Berger (Harvard) report:
"We observed the position of GRB 140515A (D'Avanzo et al; GCN 16267) at multiple frequencies with the VLA beginning 2014 May 16.00 UT (0.62 days after the burst). At a mean frequency of 21.8 GHz, we detect a radio source with a preliminary flux density of ~ 0.1 mJy at
```
RA = 12:24:15.5055 +/- 0.0005
Dec = +15:06:16.609 +/- 0.005
```
consistent with the enhanced Swft/XRT position (D'Avanzo et al.; GCN 16277) and the optical position (Fong et al.; GCN 16274). Follow-up observations are planned."
GCN Circular #16284
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), P. D'Avanzo (INAF-OAB), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-288 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 140515A (trigger #599037) (D'Avanzo, et al., GCN Circ. 16267). The BAT ground-calculated position is RA, Dec = 186.071, 15.099 deg which is
```
  RA(J2000)  =  12h 24m 17.0s
  Dec(J2000) = +15d 05' 55.8"
```
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 99%.
The mask-weighted light curve shows a double-peaked structure. The first pulse starts at ~T-22 s and peaks at ~T-18 s. The second pulse starts at ~T-10 s, peaks at ~T+2 s, and ends at ~T+4 s. T90 (15-350 keV) is 23.4 +- 2.1 sec (estimated error including systematics).
The time-averaged spectrum from T-22.0 to T+3.8 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.98 +- 0.64, and Epeak of 51.3 +- 14.7 keV (chi squared 54.37 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 5.9 +- 0.6 x 10^-7 erg/cm2 and the 1-sec peak flux measured from T+1.51 sec in the 15-150 keV band is 0.9 +- 0.1 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.85 +- 0.13 (chi squared 61.03 for 57 d.o.f.). 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/599037/BA/
GCN Circular #16338
R. Margutti, E. Berger, R. Chornock, W. Fong, T. Laskar and A. Zauderer (Harvard U.) report:
"We observed the location of GRB 140515A (D'Avanzo et al., GCN 16267) at z=6.32 (Chornock et al., GCN 16269) with the Chandra X-ray Observatory (Program 15508477, PI Margutti). Our observations started on May 25th, 07:38:38 UT, 858.6 ks after the BAT trigger. No X-ray source is detected at the position of the optical and radio afterglow (Fong et al., GCN 16274, Laskar et al., GCN 16283), with a 3-sigma count-rate limit of 1.5E-4 c/s (0.3-10 keV energy range, total exposure time of 19.8 ks).
Adopting the best fitting parameters from the total PC-mode spectrum (photon index Gamma=1.8, intrinsic neutral hydrogen column density NHint=2.3E+22 cm-2 at z=6.32), we compute an observed flux limit of 1.5E-15 erg/s/cm2 (0.3-10 keV). The Galactic hydrogen column density in the direction of the burst is NHgal=2.5E+20 cm-2 (Kalberla et al., 2005). Our observations constrain the late-time (t> 100 ks) X-ray afterglow decay to be steeper than t^-2.6.
We thank Belinda Wilkes and the entire Chandra team for making these observations possible."
1405.7400 from 30 May 14
R. Chornock et al.: GRB 140515A at z=6.33: Constraints on the End of Reionization From a Gamma-ray Burst in a Low Hydrogen Column Density Environment
We present the discovery and subsequent spectroscopy with Gemini-North of the optical afterglow of the Swift gamma-ray burst (GRB) 140515A. The spectrum exhibits a well-detected continuum at wavelengths longer than 8915 Angs with a steep decrement to zero flux blueward of 8910 Angs due to Ly-alpha absorption at redshift z~6.33. Some transmission through the Lyman-alpha forest is present at 5.2~6.
1506.03079 from 11 Jun 15
A. Melandri et al.: The high-redshift gamma-ray burst GRB140515A
High-redshift gamma-ray bursts have several advantages for the study of the distant universe, providing unique information about the structure and properties of the galaxies in which they exploded. Spectroscopic identification with large ground-based telescopes has improved our knowledge of the class of such distant events. We present the multi-wavelength analysis of the high-$z$ Swift gamma-ray burst GRB140515A ($z = 6.327$). The best estimate of the neutral hydrogen fraction of the intergalactic medium (IGM) towards the burst is $x_{HI} \leq 0.002$. The spectral absorption lines detected for this event are the weakest lines ever observed in gamma-ray burst afterglows, suggesting that GRB140515A exploded in a very low density environment. Its circum-burst medium is characterised by an average extinction (A$_{\rm V} \sim 0.1$) that seems to be typical of $z \ge 6$ events. The observed multi-band light curves are explained either with a very flat injected spectrum ($p = 1.7$) or with a multi-component emission ($p = 2.1$). In the second case a long-lasting central engine activity is needed in order to explain the late time X-ray emission. The possible origin of GRB140515A from a Pop III (or from a Pop II stars with local environment enriched by Pop III) massive star is unlikely.
1512.07808 from 25 Dec 15
J. T. W. McGuire et al.: Detection of three Gamma-Ray Burst host galaxies at $z\sim6$
Gamma-ray bursts allow us to pinpoint and study star-forming galaxies in the early universe, thanks to their immense luminosities and association with deaths of massive stars. We present {\em Hubble Space Telescope} Wide Field Camera 3 detections of three {\em Swift} GRBs lying at redshifts $z = 5.913$ (GRB 130606A), $z = 6.295$ (GRB 050904), and $z = 6.327$ (GRB 140515A) in the F140W (wide-$JH$ band, $\lambda_{\rm{obs}}\sim1.4\,\mu m$) filter. The hosts have magnitudes (corrected for Galactic extinction) of $m_{\rm{\lambda_{obs},AB}}= 26.26^{+0.12}_{-0.14}, 27.63^{+0.16}_{-0.18},$ and $28.23^{+0.24}_{-0.30}$ respectively. In all three cases the probability of chance coincidence of lower redshift galaxies is $\lesssim1.5\%$, indicating that the detected galaxies are most likely the GRB hosts. These are the first detections of high redshift ($z > 5$) GRB host galaxies in emission. The galaxies have luminosities in the range $0.1-0.7\,L^{*}_{z=6}$ (with $M_{1600}^{*}=-20.95\pm0.12$), along with half-light radii in the range $0.6-1.2\,\rm{kpc}$. Both their half-light radii and luminosities are consistent with existing samples of Lyman-break galaxies at $z\sim6$. Spectroscopic analysis of the GRB afterglows indicate low metallicities ($[\rm{M/H}]\lesssim-1$) and dust extinction ($A_{\rm{V}}\lesssim0.1$) along the line of sight. We consider the implications of these luminosities for their possible star formation histories and the potential for emission line metallicity determinations with {\em James Webb Space Telescope} spectroscopy.

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Jochen Greiner, last update: 28-Dec-2015 [Disclaimer]