Gamma-ray Burst 080413

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:54:33 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.290d {+19h 09m 10s} (J2000),
                 287.419d {+19h 09m 41s} (current),
                 286.509d {+19h 06m 02s} (1950)
GRB_DEC:         -27.679d {-27d 40' 44"} (J2000),
                 -27.665d {-27d 39' 55"} (current),
                 -27.760d {-27d 45' 35"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3614 [cnts]    Image_Peak=209 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   124     E_range: 25-100 keV
BKG_INTEN:       43179 [cnts]
BKG_TIME:        10445.28 SOD {02:54:05.28} UT
BKG_DUR:         8 [sec]
GRB_DATE:        14569 TJD;   104 DOY;   08/04/13
GRB_TIME:        10459.30 SOD {02:54:19.30} UT
GRB_PHI:         -90.59 [deg]
GRB_THETA:        16.69 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.65 [sigma]
IMAGE_SIGNIF:    9.06 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2 +22  +0  +1 +14  +1 
SUN_POSTN:        21.80d {+01h 27m 13s}   +9.15d {+09d 08' 50"}
SUN_DIST:         98.09 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.59d {+08h 02m 21s}  +23.03d {+23d 02' 06"}
MOON_DIST:       167.24 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      285.32, -5.15 [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 = 90.68,18.14 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:55:57 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.2978d {+19h 09m 11.4s} (J2000),
                 287.4270d {+19h 09m 42.4s} (current),
                 286.5173d {+19h 06m 04.1s} (1950)
GRB_DEC:         -27.6779d {-27d 40' 40.4"} (J2000),
                 -27.6641d {-27d 39' 50.9"} (current),
                 -27.7589d {-27d 45' 31.9"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       128 [cnts]
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10519.97 SOD {02:55:19.97} UT,   60.7 [sec] since BAT Trigger Time
CENTROID_X:      280.08,  raw= 280  [pixels]
CENTROID_Y:      301.95,  raw= 302  [pixels]
ROLL:            83.95 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   9.33
GRB_POS_XRT_Z:   -52.37
IMAGE_URL:       sw00309096000msxps_rw.img
SUN_POSTN:        21.80d {+01h 27m 13s}   +9.15d {+09d 08' 51"}
SUN_DIST:         98.08 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.60d {+08h 02m 25s}  +23.03d {+23d 01' 52"}
MOON_DIST:       167.23 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.53,-15.83 [deg] galactic lon,lat of the burst
ECL_COORDS:      285.33, -5.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:56:01 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.2978d {+19h 09m 11.4s} (J2000),
                 287.4270d {+19h 09m 42.4s} (current),
                 286.5173d {+19h 06m 04.1s} (1950)
GRB_DEC:         -27.6779d {-27d 40' 40.4"} (J2000),
                 -27.6641d {-27d 39' 50.9"} (current),
                 -27.7589d {-27d 45' 31.9"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       128 [cnts]
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10519.97 SOD {02:55:19.97} UT,   60.7 [sec] since BAT Trigger Time
CENTROID_X:      280.08,  raw= 280  [pixels]
CENTROID_Y:      301.95,  raw= 302  [pixels]
ROLL:            83.95 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   9.33
GRB_POS_XRT_Z:   -52.37
IMAGE_URL:       sw00309096000msxps_rw.img
SUN_POSTN:        21.80d {+01h 27m 13s}   +9.15d {+09d 08' 51"}
SUN_DIST:         98.08 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.60d {+08h 02m 25s}  +23.03d {+23d 01' 52"}
MOON_DIST:       167.23 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.53,-15.83 [deg] galactic lon,lat of the burst
ECL_COORDS:      285.33, -5.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:55:47 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.2978d {+19h 09m 11.4s} (J2000),
                 287.4270d {+19h 09m 42.4s} (current),
                 286.5173d {+19h 06m 04.1s} (1950)
GRB_DEC:         -27.6779d {-27d 40' 40.4"} (J2000),
                 -27.6641d {-27d 39' 50.9"} (current),
                 -27.7589d {-27d 45' 31.9"} (1950)
GRB_ERROR:       4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       3.66e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.31 [sigma]
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10519.97 SOD {02:55:19.97} UT,   60.7 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.25 261.19 243.49
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:        21.80d {+01h 27m 13s}   +9.15d {+09d 08' 51"}
SUN_DIST:         98.08 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.60d {+08h 02m 24s}  +23.03d {+23d 01' 54"}
MOON_DIST:       167.23 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.53,-15.83 [deg] galactic lon,lat of the burst
ECL_COORDS:      285.33, -5.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:58:07 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.290d {+19h 09m 10s} (J2000),
                 287.419d {+19h 09m 41s} (current),
                 286.509d {+19h 06m 02s} (1950)
GRB_DEC:         -27.679d {-27d 40' 44"} (J2000),
                 -27.665d {-27d 39' 55"} (current),
                 -27.760d {-27d 45' 35"} (1950)
GRB_DATE:        14569 TJD;   104 DOY;   08/04/13
GRB_TIME:        10459.30 SOD {02:54:19.30} UT
TRIGGER_INDEX:   124
GRB_PHI:         -90.59 [deg]
GRB_THETA:        16.69 [deg]
DELTA_TIME:      38.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.65 [sigma]
IMAGE_SIGNIF:    9.06 [sigma]
LC_URL:          sw00309096000msb.lc
SUN_POSTN:        21.81d {+01h 27m 14s}   +9.15d {+09d 08' 53"}
SUN_DIST:         98.09 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.62d {+08h 02m 30s}  +23.03d {+23d 01' 32"}
MOON_DIST:       167.21 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      285.32, -5.15 [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 = 90.68,18.14 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 02:59:18 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.282d {+19h 09m 08s} (J2000)
POINT_DEC:       -27.682d {-27d 40' 54"} (J2000)
POINT_ROLL:      83.951d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10535.27 SOD {02:55:35.27} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.525
N_STARS:         190
X_OFFSET:        574 [pixels]
Y_OFFSET:        477 [pixels]
X_MAX:           1533 [pixels]
Y_MAX:           1436 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00309096000msufc0075.fits
SUN_POSTN:        21.81d {+01h 27m 14s}   +9.15d {+09d 08' 54"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.64d {+08h 02m 32s}  +23.02d {+23d 01' 20"}
MOON_DIST:       167.19 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.32, -5.16 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:00:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.282d {+19h 09m 08s} (J2000)
POINT_DEC:       -27.682d {-27d 40' 54"} (J2000)
POINT_ROLL:      83.951d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10535.27 SOD {02:55:35.27} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.525
N_STARS:         190
X_OFFSET:        574 [pixels]
Y_OFFSET:        477 [pixels]
X_MAX:           1533 [pixels]
Y_MAX:           1436 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00309096000msufc0075.fits
SUN_POSTN:        21.81d {+01h 27m 14s}   +9.15d {+09d 08' 55"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.64d {+08h 02m 34s}  +23.02d {+23d 01' 14"}
MOON_DIST:       167.18 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.32, -5.16 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:00:41 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.282d {+19h 09m 08s} (J2000)
POINT_DEC:       -27.682d {-27d 40' 54"} (J2000)
ROLL:            83.951d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10535.27 SOD {02:55:35.27} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     229748137
X_OFFSET:        894 [pixels]
Y_OFFSET:        797 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1054
Y_GRB_POS:       957
BINNING_INDEX:   1
IM_URL:          sw00309096000msuni0075.fits
SUN_POSTN:        21.81d {+01h 27m 14s}   +9.15d {+09d 08' 55"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.65d {+08h 02m 36s}  +23.02d {+23d 01' 07"}
MOON_DIST:       167.17 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.32, -5.16 [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:     Sun 13 Apr 08 03:01:08 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.282d {+19h 09m 08s} (J2000)
POINT_DEC:       -27.682d {-27d 40' 54"} (J2000)
ROLL:            83.951d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10535.27 SOD {02:55:35.27} UT,   76.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     229748137
X_OFFSET:        894 [pixels]
Y_OFFSET:        797 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1054
Y_GRB_POS:       957
BINNING_INDEX:   1
IM_URL:          sw00309096000msuni0075.fits
SUN_POSTN:        21.81d {+01h 27m 14s}   +9.15d {+09d 08' 56"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.65d {+08h 02m 37s}  +23.02d {+23d 01' 03"}
MOON_DIST:       167.17 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.32, -5.16 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:05:26 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.279d {+19h 09m 07s} (J2000)
POINT_DEC:       -27.683d {-27d 40' 57"} (J2000)
POINT_ROLL:      83.953d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10641.27 SOD {02:57:21.27} UT,   182.0 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.547
N_STARS:         190
X_OFFSET:        574 [pixels]
Y_OFFSET:        477 [pixels]
X_MAX:           1533 [pixels]
Y_MAX:           1436 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00309096000msufc0181.fits
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 08' 59"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.70d {+08h 02m 47s}  +23.01d {+23d 00' 22"}
MOON_DIST:       167.13 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.31, -5.16 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:06:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.279d {+19h 09m 07s} (J2000)
POINT_DEC:       -27.683d {-27d 40' 57"} (J2000)
POINT_ROLL:      83.953d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10641.27 SOD {02:57:21.27} UT,   182.0 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.547
N_STARS:         190
X_OFFSET:        574 [pixels]
Y_OFFSET:        477 [pixels]
X_MAX:           1533 [pixels]
Y_MAX:           1436 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00309096000msufc0181.fits
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 09' 00"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.70d {+08h 02m 49s}  +23.00d {+23d 00' 15"}
MOON_DIST:       167.12 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.31, -5.16 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:06:58 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.279d {+19h 09m 07s} (J2000)
POINT_DEC:       -27.683d {-27d 40' 57"} (J2000)
ROLL:            83.953d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10641.27 SOD {02:57:21.27} UT,   182.0 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     229748243
X_OFFSET:        894 [pixels]
Y_OFFSET:        797 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1054
Y_GRB_POS:       957
BINNING_INDEX:   1
IM_URL:          sw00309096000msuni0181.fits
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 09' 01"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.71d {+08h 02m 51s}  +23.00d {+23d 00' 07"}
MOON_DIST:       167.11 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.31, -5.16 [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:     Sun 13 Apr 08 03:07:19 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     309096,   Seg_Num: 0
POINT_RA:        287.279d {+19h 09m 07s} (J2000)
POINT_DEC:       -27.683d {-27d 40' 57"} (J2000)
ROLL:            83.953d
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10641.27 SOD {02:57:21.27} UT,   182.0 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     229748243
X_OFFSET:        894 [pixels]
Y_OFFSET:        797 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1054
Y_GRB_POS:       957
BINNING_INDEX:   1
IM_URL:          sw00309096000msuni0181.fits
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 09' 01"}
SUN_DIST:         98.10 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.71d {+08h 02m 51s}  +23.00d {+23d 00' 04"}
MOON_DIST:       167.11 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.52,-15.82 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      285.31, -5.16 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:07:27 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.2989d {+19h 09m 11.73s} (J2000),
                 287.4281d {+19h 09m 42.73s} (current),
                 286.5184d {+19h 06m 04.42s} (1950)
GRB_DEC:         -27.6778d {-27d 40' 40.0"} (J2000),
                 -27.6640d {-27d 39' 50.5"} (current),
                 -27.7588d {-27d 45' 31.5"} (1950)
GRB_ERROR:       0.4 [arcsec radius, statistical only]
GRB_MAG:         15.19 +/- 0.50 [mag]
FILTER:          10, White
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10536.00 SOD {02:55:36.00} UT,   76.7 [sec] since BAT Trigger Time
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 09' 01"}
SUN_DIST:         98.09 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.72d {+08h 02m 52s}  +23.00d {+23d 00' 02"}
MOON_DIST:       167.13 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.53,-15.83 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      285.33, -5.15 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 13 Apr 08 03:09:06 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     309096,   Seg_Num: 0
GRB_RA:          287.2970d {+19h 09m 11.2s} (J2000),
                 287.4262d {+19h 09m 42.2s} (current),
                 286.5165d {+19h 06m 03.9s} (1950)
GRB_DEC:         -27.6785d {-27d 40' 42.5"} (J2000),
                 -27.6647d {-27d 39' 53.0"} (current),
                 -27.7595d {-27d 45' 34.0"} (1950)
GRB_ERROR:       2.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  14569 TJD;   104 DOY;   08/04/13
IMG_START_TIME:  10611.00 SOD {02:56:51.00} UT,   151.7 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        21.81d {+01h 27m 15s}   +9.15d {+09d 09' 03"}
SUN_DIST:         98.09 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:      120.73d {+08h 02m 56s}  +23.00d {+22d 59' 47"}
MOON_DIST:       167.11 [deg]
MOON_ILLUM:      54 [%]
GAL_COORDS:        9.53,-15.83 [deg] galactic lon,lat of the burst
ECL_COORDS:      285.33, -5.16 [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

GCN Circular #7593
GRB 080413: ROTSE-III Detection of Optical Counterpart
E.S. Rykoff (UCSB), W. Rujopakarn (Steward), report on behalf of the ROTSE collaboration:
ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, responded to GRB 080413A (Swift trigger 309096). The first image was at 02:54:39.7 UT, 20.4 s after the burst (6.7 s after the GCN notice time). The unfiltered images are calibrated relative to USNO A2.0. We detect a 12.8 magnitude, fading source with coordinates:
19:09:11.8 -27:40:41.6 (J2000), with positional uncertainty of 1' or better
```
start UT mag mlim(of image)
----------------------------------
02:54:39.7 12.8 15.3
```
This source is not visible in DSS (second epoch), 2MASS or the MPChecker database.
A jpeg image is available at http://www.rotse.net/images/gsb309096_3c00_img.jpg Note that the object marked 7 is the candidate in question.
Continuing observations are in progress.
GCN Circular #7594
A. P. Beardmore (U Leicester), D. N. Burrows (PSU), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), S. D. Hunsberger (PSU), J. A. Kennea (PSU), C. B. Markwardt (CRESST/GSFC/UMD), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU) and E. Troja (U Leicester/INAF-IASFPA) report on behalf of the Swift Team:
At 02:54:19 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080413 (trigger=309096). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 287.290, -27.679 which is
```
   RA(J2000) = 19h 09m 10s
   Dec(J2000) = -27d 40' 44"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a triple-peaked structure with a duration of about 55 sec. The peak count rate was ~10000 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 02:55:20.0 UT, 60.7 seconds after the BAT trigger. XRT found a bright, fading uncatalogued X-ray source located at RA, Dec 287.2978, -27.6779 which is equivalent to:
```
   RA(J2000)  = 19h 09m 11.4s
   Dec(J2000) = -27d 40' 40.4"
```
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This location is 25 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to assess possible redshift constraints using X-ray spectroscopy and the nH-z relation from Grupe et al. (2007).
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 76 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	19:09:11.76 = 287.2990
  DEC(J2000) = -27:40:40.1  = -27.6778
```
with a 1-sigma error radius of about 0.6 arc sec. This position is 3.9 arc sec. from the center of the XRT error circle. The estimated magnitude is 15.2 with a 1-sigma error of about 0.5 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.16.
GCN Circular #7595
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 080413 detected by SWIFT (trigger 309096) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
The observations started 21.8s after the GRB trigger (8.3s after the notice). The elevation of the field increased from from 11 degrees above horizon and weather conditions were poor at the beginning of observations. The first image showing stars started 480s after the trigger.
We detected the candidate couterpart mentioned by Rykoff et al. (GCNC 7593) at the following position (+/- 2 arcsec):
```
RA(J2000.0) = 19h 09m 11.85s
DEC(J2000.0) -27d 40' 43.0"
```
Unfiltered magnitudes are:
```
t0+480s to t0+570s : R > 12.5
t0+1174s to t0+1263s : R = 15.0 +/- 0.2
t0+1470s to t0+1650s : R = 15.3 +/- 0.2
t0+2035s to t0+2215s : R = 15.5 +/- 0.2
```
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon= 9.5236 lat=-15.8249 and the galactic extinction in R band is 2.4 magnitudes estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.
GCN Circular #7596
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 176 s of overlapping XRT Photon Counting mode and UVOT data for GRB 080413, 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 = 287.29829, -27.67807 which is equivalent to:
```
RA (J2000): 19h 09m 11.59s
Dec (J2000): -27d 40' 41.1"
```
with an uncertainty of 2.3 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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method.
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #7597
L.A. Antonelli, P. D'Avanzo, D. Malesani, S. Covino, D. Fugazza, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A. Meurs, L. Nicastro, E. Palazzi, E. Pian, F. Piranomonte, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, and F. Vitali, report on behalf of the REM team:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 080413A (Beardmore et al., GCN 7594) starting about 1.3 hours after the burst due to object visibility constraints. Observation started as soon as the object is risen so the Airmass was large.
A preliminary investigation of our earliest images (R,z,J,H,K) showed that the candidate optical counterpart (Rykoff et al. GCN 7593, Beardmore et al., GCN 7594, Klotz et al., GCN 7595) is observed in all bands. At the beginning of REM observation, the object had a H mag of about H=15.2 calibrated against 2MASS and not corrected for galactic extinction.
This message may be cited.
GCN Circular #7602
Christina C. Thoene, Daniele Malesani, Paul M. Vreeswijk, Johan P. U. Fynbo (DARK/NBI), Pall Jakobsson (Univ. of Hertfordshire), Cedric Ledoux and Alain Smette (ESO) report on behalf of a larger collaboration:
We observed the afterglow of GRB 080413A (GCN 7593, Rykoff & Rujopakarn; GCN 7594, Stamatikos et al.) on Apr. 13 starting UT 06:36 with UVES at the VLT. Spectra of 2700 s with low S/N were acquired in the DIC 2R and 2B settings covering the wavelength range between 3250 and 9000 AA. We detect several narrow absorption features including SII, Si II, CII, Fe II, AlII, C IV, Si IV as well as broad Lyman alpha absorption at the highest redshift system which has z=2.433 and is very likely the redshift of GRB 080413A.
We thank the Paranal staff for executing the observations, in particular Swetlana Hubrig and Jose Cortes.
GCN Circular #7603
P. Kubanek, M. Jelinek, J. Gorosabel, A. J. Castro-Tirado (IAA-CSIC Granada), L. Sabau-Graziati (INTA Madrid), A. de Ugarte Postigo (ESO Santiago), R. Hudec (ASU-CAS Ondrejov), P. Perez-Gonzalez and J. Zamorano (UCM Madrid) report on behalf of a larger collaboration:
The BOOTES-1 0.3m telescope in South Spain observed GRB 080413A, starting at 02:55:20 UT (46 sec after receiving trigger, 1 minute after GRB). A sequence of preprogrammed 6 sec, 20 and 60 sec exposures was obtained. The optical counterpart reported by Rykoff at al. (GCN 7593) is clearly detected on the initial exposures.
Further data were obtained at the 2.5m NOTin La Palma under non-optimal conditions.
GCN Circular #7604
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+454 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080413A (trigger #309096) (Beardmore, et al., GCN Circ. 7594). The BAT ground-calculated position is RA, Dec = 287.301, -27.677 deg, which is
```
   RA(J2000)  =  19h 09m 12.1s 
   Dec(J2000) = -27d 40' 36.8" 
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 81%.
The mask-weighted light curve shows four peaks. The first starting at T-0.1 sec, peaking at T+2.0 sec. The second peak overlaps with the first and peaks at ~T+7 sec. The third and fourth peaks are well separated with peaks at T+16 and T+47 sec, repsectively. The lightcurve returns to baseline at ~T+80 sec. T90 (15-350 keV) is 46 +- 1 sec (estimated error including systematics).
The time-averaged spectrum from T-0.1 to T+50.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.57 +- 0.06. The fluence in the 15-150 keV band is 3.5 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+1.64 sec in the 15-150 keV band is 5.6 +- 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/309096/BA/
GCN Circular #7605
P.A. Evans, K.L. Page, A.P. Beardmore, R.L.C. Starling (U. Leicester) and F.E. Marshall (NASA/GSFC) report on behalf of the Swift-XRT team:
We have analysed 5.2 ks of Swift XRT data for GRB 080413A (Beardmore et al. GCN Circ. 7594), from T0+67 s to T0+21000 s. The first 186 s of data were obtained in Windowed Timing (WT mode); the remainder in Photon Counting mode. The best XRT position for this object is the UVOT-enhanced position given in Osborne et al. (GCN Circ. 7596).
The X-ray light curve is well fitted by a power-law decay, with an initial decay slope of 2.87 (+/- 0.19) up to T0+175 (+23/-16) s, at which point the decay shallows to a slope of 1.10 (+0.06/-0.07).
A spectrum obtained from all of the WT mode data can be modelled with an absorbed power-law with a photon index gamma=3.12 (+0.16/-0.15). A redshifted absorbing column of 1.53 (+0.43/-0.38) x 10^22 cm^-2, at a redshift of z=2.433 (Thoene et al. GCN Circ 7602) is necessary in addition to the Galactic column of 8.71 x 10^20 cm^-2 (Kalberla et al. 2005). The observed (unabsorbed) 0.3-10 keV flux in this spectrum is 4.1 x 10^-10 (1.71 x 10^-9) erg cm^-2 s^-1.
If the source continues to decay at the present rate, we predict a count rate of 3.51 x 10^-3 count/sec at T0+24 hours, which correponds to a 0.3-10 keV observed (unabsorbed) flux of 9.54 x 10^-14 (2.72 x 10^-13) erg cms^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular #7607
S. R. Oates and F. E. Marshall report on behalf of the Swift/UVOT team.
The Swift/UVOT observed the field of GRB 080413A starting at 77s after the BAT trigger (Beardmore et al., GCN 7594). We detect the afterglow in white,v,b and u filters at the position:
```
RA(J2000.0)  =   19:09:11.76
DEC(J2000.0) =  -27:40:40.27
```
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence). This position is consistent with the enhanced XRT position and the position reported by ROSTE-III (Rykoff et al., GCN 7593).
The magnitudes and 3 sigma upper limits are reported below:
```
Filter    T_Mid(s)   Expo(s)          Magnitude/3sigUL
-----------------------------------------------------
White     126          98               15.37 +/- 0.01
White     5478         197              19.74 +/- 0.17
v         268          169              15.08 +/- 0.03
v         5888         197              19.16 +/- 0.51
b         5273         197              19.33 +/- 0.21
u         5068         197              19.05 +/- 0.22
w1        4863         197              >19.55
m2        4658         197              >19.48
w2        5684         197              >19.57
-----------------------------------------------------
```
The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.16 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT flight system described in Poole et al. (2008,MNRAS,383,627).
GCN Circular #7609
B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:
Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 080413a (GCN 7594, Beardmore et al.), starting at 2008-04-13 05:48 UT, which is ~2.9 hours post-burst. Several dithered images were obtained in each filter, with total summed exposure times of 180s in each of BRIYJK and 120s in each of H and V.
The GRB afterglow (GCN 7593 Rykoff & Rujopakarn; GCN 7594, Beardmore et al.) is detected in all our images. At a mid-exposure time of 2008-04-13 06:02 (~3.1 hours post-burst) the afterglow has the following magnitudes (which have not been corrected for Galactic reddening):
```
B= 20.88 +/- 0.10
V= 20.25 +/- 0.11
R= 19.25 +/- 0.05
I= 18.84 +/- 0.06
J= 18.23 +/- 0.23
H= 17.05 +/- 0.15
K= 16.19 +/- 0.12
```
Optical photometry is calibrated against Landolt standard stars and IR photometry is calibrated against 2MASS stars in the field.
Between 3.1 and 5.1 hours post burst, the afterglow decays by ~0.75 magnitudes, indicating an approximate decay rate of alpha = -1.4 (where afterglow flux is proportional to t^alpha).
GCN Circular #7614
Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf of the Caltech-NRAO-Carnegie GRB Collaboration:
"We used the Very Large Array to observe the field of view toward GRB 080413A (GCN 7594) at a frequency of 8.46 GHz at 2008 April 14.53 UT. We do not detect the GRB afterglow at the ROTSE optical position (GCN 7593). The flux density at the GRB afterglow position is -61 +/- 49 uJy.
The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN Circular #7616
A. Cucchiara and D. B. Fox (Penn State) with S. B. Cenko (Caltech), report on behalf of a larger collaboration:
"Starting on 2008 April 13.27 UT we observed GRB 080413A (GCN 7593 and 7594) with the GMOS spectrograph on the Gemini South telescope. We obtained 2x1200-sec spectra in the wavelength range 3900-8000A. The resolution of our spectrum is 5.2 Ang/pixel (R ~1200 at 6000A). We clearly observe several metal absorption features corresponding to the SiIV (1393,1402 A), CIV (1548, 1550A), SiII (1526A), and AlII (1670A) transitions. A Lyman break is also present at the blue edge of our spectra (~ 4170A). These identifications are consistent with a host galaxy redshift of z = 2.43, confirming the result reported from VLT observations by Thoene et al.(GCN 7602)."
GCN Circular #7622
A. Fukui, Y. Itow, T. Sumi (STE Lab, Nagoya Univ.), and P. Tristram (Canterbury Univ.) on behalf of the MOA Collabration (Bond et al. 2001, Sumi et al. 2003) report:
We observed the optical afterglow of GRB080413A (GCN 7593, Rykoff & Rujopakarn; GCN 7594, Stamatikos et al.) on Apr. 13 between 12:29:16.4 UTC and 14:13:06.6 UTC, corresponding to about 9.5-11 h after the burst, with the 1.8m MOA-II telescope at Mt. John observatory in New Zealand. Total 5 images were obtained with a wide- band Red filter (center wavelength ~ 750nm and FWHM ~ 250nm) and we could identify the faint afterglow within the error circle (<0.5"). The identified R.A. Dec. are 19:09:11.752 -27:40:39.99 with an uncertainty of 0.14" (radius, 1sigma) and following are the photometric results: I magnitude = 20.24 +/- 0.32 at the mid-exposure time of 2008-04-13 12:29:16.4 UTC, 20.09 +/- 0.19 at 12:51:10.7 UTC, 21.40 +/- 0.61 at 13:03:0.1 UTC, 20.05 +/- 0.17 at 13:42:47.0 UTC, and 20.75 +/- 0.25 at 14:13:06.6 UTC. These photometry were done by using the IRAF and calibrated against the USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.
GCN Circular #7624
T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN), T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima U.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), M. Tashiro, Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.), K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki), M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:
The long GRB 080413A (Swift/BAT trigger #309096 ; Beardmore et al., GCN 7594) was detected by the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 02:54:18.648 UT (=T0). The observed light curve shows a clear double-peaked structure at T0+2s and T0+16s, and possible weak peak at T0+45s, with a total duration (T90) of about 19 seconds. The fluence in 150 - 1000 keV was (2.2 +/- 0.5) x 10^-6 erg/cm^2. The 1-s peak flux measured from T0+2s was 0.77 +/- 0.19 photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0+0s to T0+20s is fitted by a single power-law with a photon index of 2.4 +/- 0.4 (chi^2/d.o.f = 15.1/10) in 150 - 1000 keV. All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included.
The light curves with 1-sec time resolution for this burst are now available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html
GCN Circular #7625
A. Gomboc (Ljubljana), C. Guidorzi (U. Bicocca/INAF-OAB), A. Melandri, I.A. Steele, C.G. Mundell, D.F. Bersier, M.F. Bode, M.J. Burgdorf, S.N. Fraser, S. Kobayashi, C.J. Mottram, R.J. Smith (Liverpool JMU), P. O'Brien, N. Bannister, N. Tanvir (U. Leicester) report on behalf of larger GRB collaboration:
The Liverpool Telescope observed the field of GRB 080413A (trigger=309096, Beardmore et al. GCN 7594) under poor weather conditions starting 2-hr after the trigger. Observations continued with the Faulkes Telescope South.
In our coadded frames we do not detect any source at the position of the optical afterglow (Beardmore et al. GCN 7594, Rykoff & Rujopakarn GCN 7593) down to the limiting magnitudes reported below.
```
Telescope     Filter  Tstart(hr)  Tstop(hr)    Exposure(s)    M_lim
----------------------------------------------------------------------
Liverpool        R      2.0          2.5          760         15.7
Faulkes South    R     12.2         12.2           30         19.2
                 I     12.2         13.1         2080         21.7
----------------------------------------------------------------------
```
Magnitudes were calibrated with respect to USNOB1 R2 and I.
GCN Circular #7630
M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA) K. Yamaoka, S. Sugita (Aoyama Gakuin U.), T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN), T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima U.), M. Tashiro, Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.), K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki), , S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU) (i.e. the Swift-BAT team):
report:
We performed the Suzaku/WAM and Swift/BAT joint fit spectral analysis of GRB 080413A (Swift/BAT trigger #309096; Beardmore et al., GCN 7594). The time interval of the spectral data for each instrument is chosen from T0(WAM)-1 to T0(WAM)+22 sec where T0(WAM) is the trigger time of WAM at 02:54:18.648 UTC. This time interval includes the initial two peaks, but not the relatively soft third peak around T0(WAM)+45 sec which is clearly visible in the BAT data (Tueller et al., GCN 7604). The energy ranges which we used in the joint spectral analysis are 13-150 keV and 150-1000 keV for Swift/BAT and Suzaku/WAM respectively. The spectral data of two instruments are fit with the spectral model multiplied by the constant factor to take into account the systematic uncertainties in the response matrices of each instrument.
The spectrum is well fit with a power-law with exponential cutoff model (dN/dE ~ E^{alpha} * exp(-(2+alpha)*E/Epeak)). The constant factors of each instrument agree within 20%. No systematic residual from the best fit model is seen in the spectral data of each instrument. The best fit spectral parameters are: alpha = -1.2 +- 0.1 and Epeak = 170 (-40/+80) keV (chi2/dof = 75/73). The energy fluence in the 15-1000 keV band calculated by a power-law with exponential cutoff model for this 23 sec interval is 4.8 (-1.2/+0.4) x 10^-6 erg/cm2 (assuming the constant factor of the BAT is fixed to 1).
Assuming z = 2.433 (Thoene et al., GCN 7602) and a standard cosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda = 0.73, the isotropic energy release is E_iso ~8x10^52 erg in 1 keV to 10 MeV at the GRB rest frame.
All the quoted errors are at the 90% confidence level.
GCN Report 129.1
GCN_Report 129.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_129_1.pdf by F.E. Marshall at GSFC titled: "Final Swift Observations of GRB 080413A"

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Jochen Greiner, last update: 25-Apr-2008 [Disclaimer]