Gamma-ray Burst 080523

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:22:34 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.732d {+01h 22m 56s} (J2000),
                  20.805d {+01h 23m 13s} (current),
                  20.293d {+01h 21m 10s} (1950)
GRB_DEC:         -64.053d {-64d 03' 12"} (J2000),
                 -64.010d {-64d 00' 34"} (current),
                 -64.314d {-64d 18' 50"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       11612 [cnts]    Image_Peak=291 [image_cnts]
TRIGGER_DUR:     3.072 [sec] 
TRIGGER_INDEX:   474     E_range: 25-100 keV
BKG_INTEN:       104177 [cnts]
BKG_TIME:        76869.18 SOD {21:21:09.18} UT
BKG_DUR:         32 [sec]
GRB_DATE:        14609 TJD;   144 DOY;   08/05/23
GRB_TIME:        76911.29 SOD {21:21:51.29} UT
GRB_PHI:         -170.82 [deg]
GRB_THETA:         9.70 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.22 [sigma]
IMAGE_SIGNIF:    7.00 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  +1  +0  +0  +0  +1 
SUN_POSTN:        61.06d {+04h 04m 13s}  +20.78d {+20d 46' 31"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.22d {+19h 04m 52s}  -25.65d {-25d 39' 01"}
MOON_DIST:        69.05 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      332.22,-62.45 [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 = 159.49,2.67 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:23:51 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.7992d {+01h 23m 11.8s} (J2000),
                  20.8726d {+01h 23m 29.4s} (current),
                  20.3608d {+01h 21m 26.5s} (1950)
GRB_DEC:         -64.0322d {-64d 01' 55.9"} (J2000),
                 -63.9885d {-63d 59' 18.7"} (current),
                 -64.2928d {-64d 17' 34.2"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.31e-09 [erg/cm2/sec]
GRB_SIGNIF:      9.21 [sigma]
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  76997.67 SOD {21:23:17.67} UT,   86.4 [sec] since BAT Trigger Time
TAM[0-3]:        327.64 237.28 261.43 243.22
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 31"}
SUN_DIST:         90.32 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.23d {+19h 04m 55s}  -25.65d {-25d 38' 54"}
MOON_DIST:        69.08 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.20,-52.74 [deg] galactic lon,lat of the burst
ECL_COORDS:      332.29,-62.46 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.18 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:24:02 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.7992d {+01h 23m 11.8s} (J2000),
                  20.8726d {+01h 23m 29.4s} (current),
                  20.3608d {+01h 21m 26.5s} (1950)
GRB_DEC:         -64.0322d {-64d 01' 55.9"} (J2000),
                 -63.9885d {-63d 59' 18.7"} (current),
                 -64.2928d {-64d 17' 34.2"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       85 [cnts]
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  76997.67 SOD {21:23:17.67} UT,   86.4 [sec] since BAT Trigger Time
CENTROID_X:      258.09,  raw= 258  [pixels]
CENTROID_Y:      282.01,  raw= 282  [pixels]
ROLL:            37.22 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -37.67
GRB_POS_XRT_Z:   -104.19
IMAGE_URL:       sw00312242000msxps_rw.img
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 32"}
SUN_DIST:         90.32 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.23d {+19h 04m 56s}  -25.65d {-25d 38' 53"}
MOON_DIST:        69.08 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.20,-52.74 [deg] galactic lon,lat of the burst
ECL_COORDS:      332.29,-62.46 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:24:08 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.7992d {+01h 23m 11.8s} (J2000),
                  20.8726d {+01h 23m 29.4s} (current),
                  20.3608d {+01h 21m 26.5s} (1950)
GRB_DEC:         -64.0322d {-64d 01' 55.9"} (J2000),
                 -63.9885d {-63d 59' 18.7"} (current),
                 -64.2928d {-64d 17' 34.2"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       85 [cnts]
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  76997.67 SOD {21:23:17.67} UT,   86.4 [sec] since BAT Trigger Time
CENTROID_X:      258.09,  raw= 258  [pixels]
CENTROID_Y:      282.01,  raw= 282  [pixels]
ROLL:            37.22 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -37.67
GRB_POS_XRT_Z:   -104.19
IMAGE_URL:       sw00312242000msxps_rw.img
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 32"}
SUN_DIST:         90.32 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.23d {+19h 04m 56s}  -25.65d {-25d 38' 53"}
MOON_DIST:        69.08 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.20,-52.74 [deg] galactic lon,lat of the burst
ECL_COORDS:      332.29,-62.46 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:25:23 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.732d {+01h 22m 56s} (J2000),
                  20.805d {+01h 23m 13s} (current),
                  20.293d {+01h 21m 10s} (1950)
GRB_DEC:         -64.053d {-64d 03' 12"} (J2000),
                 -64.010d {-64d 00' 34"} (current),
                 -64.314d {-64d 18' 50"} (1950)
GRB_DATE:        14609 TJD;   144 DOY;   08/05/23
GRB_TIME:        76911.29 SOD {21:21:51.29} UT
TRIGGER_INDEX:   474
GRB_PHI:         -170.82 [deg]
GRB_THETA:         9.70 [deg]
DELTA_TIME:      -51.00 [sec]
TRIGGER_DUR:     3.072 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.22 [sigma]
IMAGE_SIGNIF:    7.00 [sigma]
LC_URL:          sw00312242000msb.lc
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 32"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.24d {+19h 04m 59s}  -25.65d {-25d 38' 46"}
MOON_DIST:        69.05 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      332.22,-62.45 [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 = 159.49,2.67 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:26:02 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
POINT_ROLL:      37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77021.66 SOD {21:23:41.66} UT,   110.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.428
N_STARS:         190
X_OFFSET:        0 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           2047 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    2
SL_URL:          sw00312242000msufc0110.fits
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 33"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.25d {+19h 05m 00s}  -25.65d {-25d 38' 43"}
MOON_DIST:        69.05 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:26:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
POINT_ROLL:      37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77021.66 SOD {21:23:41.66} UT,   110.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.428
N_STARS:         190
X_OFFSET:        0 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           2047 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    2
SL_URL:          sw00312242000msufc0110.fits
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 33"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.25d {+19h 05m 01s}  -25.64d {-25d 38' 40"}
MOON_DIST:        69.05 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:27:26 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
ROLL:            37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77021.66 SOD {21:23:41.66} UT,   110.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     233270624
X_OFFSET:        1016 [pixels]
Y_OFFSET:        825 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1176
Y_GRB_POS:       985
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0110.fits
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 33"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.26d {+19h 05m 03s}  -25.64d {-25d 38' 35"}
MOON_DIST:        69.05 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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 23 May 08 21:27:45 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
ROLL:            37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77021.66 SOD {21:23:41.66} UT,   110.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     233270624
X_OFFSET:        1016 [pixels]
Y_OFFSET:        825 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1176
Y_GRB_POS:       985
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0110.fits
SUN_POSTN:        61.06d {+04h 04m 14s}  +20.78d {+20d 46' 33"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.27d {+19h 05m 04s}  -25.64d {-25d 38' 33"}
MOON_DIST:        69.04 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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 Circular #7767
M. C. Stroh (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), C. Gronwall (PSU), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA), V. Mangano (INAF-IASFPA), P. T. O'Brien (U Leicester), D. M. Palmer (LANL), D. Perez (U Leicester), J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU), T. N. Ukwatta (GSFC/GWU) and D. E. Vanden Berk (PSU) report on behalf of the Swift Team:
At 21:21:51 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080523 (trigger=312242). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 20.732, -64.053 which is
```
   RA(J2000) = 01h 22m 56s
   Dec(J2000) = -64d 03' 12"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak with a duration of about 15 sec. The peak count rate was ~700 counts/sec (15-350 keV), at ~5 sec after the trigger.
The XRT began observing the field at 21:23:17.7 UT, 86.4 seconds after the BAT trigger. XRT found a bright, uncatalogued, fading X-ray source located at RA, Dec 20.7992, -64.0322 which is equivalent to:
```
   RA(J2000)  = 01h 23m 11.8s
   Dec(J2000) = -64d 01' 55.9"
```
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 129 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 110 seconds after the BAT trigger. No afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 18.5 mag. data for the list of sources generated on-board are not available at this time. No correction has been made for the expected extinction corresponding to E(B-V) of 0.03.
Burst Advocate for this burst is M. C. Stroh (stroh AT astroh.org). 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 23 May 08 21:36:39 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.742d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.051d {-64d 03' 02"} (J2000)
POINT_ROLL:      37.221d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77127.79 SOD {21:25:27.79} UT,   216.5 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.820
N_STARS:         127
X_OFFSET:        0 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           2047 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00312242000msufc0216.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 37"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.35d {+19h 05m 23s}  -25.63d {-25d 37' 45"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.24,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:37:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.742d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.051d {-64d 03' 02"} (J2000)
POINT_ROLL:      37.221d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77127.79 SOD {21:25:27.79} UT,   216.5 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.820
N_STARS:         127
X_OFFSET:        0 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           2047 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00312242000msufc0216.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 38"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.35d {+19h 05m 24s}  -25.63d {-25d 37' 43"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      88 [%]
GAL_COORDS:      297.24,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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 23 May 08 21:38:06 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.742d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.051d {-64d 03' 02"} (J2000)
ROLL:            37.221d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77127.79 SOD {21:25:27.79} UT,   216.5 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     233270730
X_OFFSET:        1016 [pixels]
Y_OFFSET:        825 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1176
Y_GRB_POS:       985
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0216.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 38"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.36d {+19h 05m 26s}  -25.63d {-25d 37' 37"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.24,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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 23 May 08 21:38:35 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.742d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.051d {-64d 03' 02"} (J2000)
ROLL:            37.221d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77127.79 SOD {21:25:27.79} UT,   216.5 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     233270730
X_OFFSET:        1016 [pixels]
Y_OFFSET:        825 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1176
Y_GRB_POS:       985
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0216.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 38"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.36d {+19h 05m 27s}  -25.63d {-25d 37' 35"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.24,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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:     Fri 23 May 08 21:39:03 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
POINT_ROLL:      37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77777.49 SOD {21:36:17.49} UT,   866.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.129
N_STARS:         4
X_OFFSET:        696 [pixels]
Y_OFFSET:        505 [pixels]
X_MAX:           1655 [pixels]
Y_MAX:           1464 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw00312242000msufc0866.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 39"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.37d {+19h 05m 28s}  -25.63d {-25d 37' 32"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.  
COMMENTS:        The Pointing RA,Dec,Roll values came from the 1st SrcList Notice.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:39:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
POINT_ROLL:      37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77777.49 SOD {21:36:17.49} UT,   866.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.129
N_STARS:         4
X_OFFSET:        696 [pixels]
Y_OFFSET:        505 [pixels]
X_MAX:           1655 [pixels]
Y_MAX:           1464 [pixels]
DET_THRESH:      4
PHOTO_THRESH:    2
SL_URL:          sw00312242000msufc0866.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 39"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.37d {+19h 05m 29s}  -25.63d {-25d 37' 29"}
MOON_DIST:        69.02 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:40:21 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
ROLL:            37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77777.49 SOD {21:36:17.49} UT,   866.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     233271380
X_OFFSET:        1015 [pixels]
Y_OFFSET:        824 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       984
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0866.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 39"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.38d {+19h 05m 31s}  -25.62d {-25d 37' 25"}
MOON_DIST:        69.01 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The Pointing RA,Dec,Roll values came from the 1st Image Notice.  
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 23 May 08 21:40:38 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     312242,   Seg_Num: 0
POINT_RA:         20.741d {+01h 22m 58s} (J2000)
POINT_DEC:       -64.050d {-64d 02' 58"} (J2000)
ROLL:            37.222d
IMG_START_DATE:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77777.49 SOD {21:36:17.49} UT,   866.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     233271380
X_OFFSET:        1015 [pixels]
Y_OFFSET:        824 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       984
BINNING_INDEX:   1
IM_URL:          sw00312242000msuni0866.fits
SUN_POSTN:        61.07d {+04h 04m 16s}  +20.78d {+20d 46' 39"}
SUN_DIST:         90.35 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.38d {+19h 05m 32s}  -25.62d {-25d 37' 23"}
MOON_DIST:        69.01 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.25,-52.73 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      332.23,-62.45 [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_sources_image.fits.gz file does not exist; skipping the attachment.  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 23 May 08 21:43:10 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     312242,   Seg_Num: 0
GRB_RA:           20.7985d {+01h 23m 11.6s} (J2000),
                  20.8719d {+01h 23m 29.2s} (current),
                  20.3601d {+01h 21m 26.4s} (1950)
GRB_DEC:         -64.0317d {-64d 01' 54.1"} (J2000),
                 -63.9880d {-63d 59' 16.9"} (current),
                 -64.2923d {-64d 17' 32.4"} (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:  14609 TJD;   144 DOY;   08/05/23
IMG_START_TIME:  77265.00 SOD {21:27:45.00} UT,   353.7 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        61.07d {+04h 04m 17s}  +20.78d {+20d 46' 40"}
SUN_DIST:         90.32 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:      286.41d {+19h 05m 37s}  -25.62d {-25d 37' 10"}
MOON_DIST:        69.04 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      297.20,-52.74 [deg] galactic lon,lat of the burst
ECL_COORDS:      332.29,-62.46 [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.

GCN Circular #7768
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 463 s of overlapping XRT Photon Counting mode and UVOT data for GRB 080523, 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 = 20.79796, -64.03081 which is equivalent to:
```
RA (J2000): 01h 23m 11.51s
Dec (J2000): -64d 01' 50.9"
```
with an uncertainty of 1.5 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 #7769
N. P. M. Kuin (MSSL/UCL), and M. C. Stroh (PSU), report on behalf of the Swift UVOT team
The Swift UltraViolet/Optical Telescope (UVOT) began observations of GRB 080523, on May 23, 2008, at UT, 112 seconds after the initial Swift BAT trigger (Stroh et al., GCN Circ. 7767). We detect no source at the enhanced Swift XRT position (Osborne, GCN Circ.7768).
The 3-sigma limiting magnitudes for GRB080523 are given below for the two initial observations, and for summed observations in each of the UVOT filters:
```
Filter Tstart(s) Tstop(s) Exp(s) Magnitude

white    112       211     99.8    > 20.78
v        218       617    399.8    > 19.93

white    112     12001   1211.2    > 21.80
v        218      6037    819.2    > 19.86
uvm2     624      6242    439.2    > 20.15
uvw1     649      6448    439.2    > 20.20
u        673      6649    435.9    > 19.92
b        698     11088   1118.9    > 21.56
uvw2     728     12430    841.6    > 20.77
```
The values quoted above are on the UVOT Photometric System (Poole et al, 2008, MNRAS 383,627). They are not corrected for the expected galactic reddening of E(B-V) = 0.025 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #7770
Johan P. U. Fynbo, Daniele Malesani (DARK), Pall Jakobsson (Univ. Hertfordshire), Bo Milvang-Jensen and Jens Hjorth (DARK), report on behalf of a larger collaboration:
We observed the field of GRB 080523 (Stroh et al., GCN 7767) with the ESO VLT equipped with FORS2. Photometric observations were conducted on 2008 May 24, between 8:14 and 8:27 UT (about 10.9 hr after the GRB). Inside the revised XRT error circle (Osborne et al., GCN 7768), we detect a faint source at coordinates (J2000):
```
RA = 01:23:11.61
Dec = -64:01:51.8
```
Lacking any information on variability, we cannot assess whether this source is associated with GRB 080523.
A spectrum of the object shows detection of continuum in the blue down to 4200 AA, implying a redshift limit z < 2.5. Further analysis is underway.
We note the presence of two further, faint sources close to, but slightly outside of, the refined XRT error circle at (RA, Dec) = (01:23:11.21, -64:01:53.9) and (01:23:10.88, -64:01:50.4).
We acknowledge excellent support and positive initative from the ESO observing staff, particularly Yuri Beletsky and Patricia Guajardo.
GCN Circular #7772
D. Palmer (LANL), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), M. C. Stroh (PSU), J. Tueller (GSFC), T. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080523 (trigger #312242) (Stroh, et al., GCN Circ. 7767). The BAT ground-calculated position is RA, Dec = 20.769, -64.060 deg, which is
```
   RA(J2000)  =  01h 23m 04.4s 
   Dec(J2000) = -64d 03' 36.0" 
```
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a FRED-like peak starting at ~T-10 sec, peaking at ~T+4, and ending at ~T+80 sec. There is a weak second peak starting,ending at 80,110 sec, respectively. T90 (15-350 keV) is 102 +- 15 sec (estimated error including systematics).
The time-averaged spectrum from T-6.1 to T+111.9 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.65 +- 0.18. The fluence in the 15-150 keV band is 8.8 +- 1.0 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+3.89 sec in the 15-150 keV band is 0.5 +- 0.1 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/312242/BA/
This burst satisfies Sakamoto/Ukwatta Swift-BAT possible high-z criteria (Ukwatta et al. arXiv:0802.3815).
```
1) Power Law photon index = 1.65     (PL photon index < 2)
2) 1-s peak photon flux   = 0.51     (1-s peak photon flux < 1.0 ph/cm2/s)
3) Light curve variance   = 1.2e-05  (Variance < 0.0001)
4) T90/(Peak photon flux) = 201      (T90/(Peak photon flux) > 100)
```
Based on a limited sample of bursts, these criteria yield an 85% chance it has a redshift greater than 3.5.
GCN Circular #7773
M. C. Stroh and D. Grupe (PSU) report on behalf of the Swift-XRT Team:
We have analyzed the first eight orbits of Swift-XRT data obtained for GRB 080523 (Stroh et al. GCN Circ. 7767), totaling 250 s of Windowed Timing (WT) data and 11.8ks of Photon Counting (PC) data.
The light curve can be described as a single broken power-law with an initial decay index of 2.17 +/- 0.04 followed by a shallower decay index of 0.56 +/- 0.27 with a break at T+3.5ks. We predict a count rate at T+48 hours of 3.2e-3 cts/s.
The WT data (93 - 343 seconds) can be modeled as an absorbed power law with photon index of 2.17 +/- 0.04 and a total absorbing column density that is consistent with the Galactic value of 2.1e20 cm^-2. The 0.3-10 keV absorbed (unabsorbed) flux during this time is 4.58e-10 (4.99e-10) erg cm^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular #7779
D. Malesani, J. P. U. Fynbo (DARK/NBI), A. de Ugarte Postigo (ESO), P. Jakobsson (Univ. Hertfordshire), J. Hjorth, B. Milvang-Jensen (DARK/NBI), report on behalf of a larger collaboration:
We observed again the field of GRB 080523 (Stroh et al., GCN 7767) with the ESO VLT equipped with the FORS2 camera. Observations were carried out on 2008 May 28, at mean time 9:35 UT (4.5 days after the GRB) in the R band.
The optical source identified by Fynbo et al. (GCN 7770) has clearly faded since our previous observation by at least 1.5 mag. This confirms that the object is the afterglow of GRB 080523. The refined coordinates (J2000, against USNO-B1.0) are
```
RA = 01:23:11.56
Dec = -64:01:51.59
```
Residual, marginally significant emission is still detected close to the afterglow position. It is unclear whether this is related to the GRB.
A finding chart showing the field in the two epochs is posted at
http://www.astro.ku.dk/~malesani/GRB/080523/080523_finder.jpg
Close inspection of our spectra (Fynbo et al., GCN 7770) fails to reveal any convincing absorption or emission feature. The object has a blue continuum, and flux is detected down to ~4070 AA. A conservative limit to the redshift is set by the absence of Lyman-alpha forest redward of ~4900 AA, which implies z < 3. This limit rules out a high redshift as suggested by the burst gamma-ray properties (Palmer et al., GCN 7772).
We acknowledge significant support from the ESO staff at Paranal, particularly Linda Schmidtobreick.
GCN Circular #8491
Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope National Facility), Steven Tingay (Curtin Institute of Radio Astronomy), Chris Phillips (Australia Telescope National Facility), Gregory Taylor (University of New Mexico), Mark Wieringa (Australia Telescope National Facility) and Ralph Martin (Perth Observatory) report:
We observed the BAT refined position of the GRB 080523 (GCN 7772) at 4.8 GHz with the Australia Telescope Compact Array (ATCA) on June 01, 2008 between 04:12:15 UT and 06:37:35 UT.
We did not detect a radio source at the BAT position of the GRB 080523 (GCN 7772). The radio flux density at the GRB position is -0.069 +/- 0.172 mJy at 4.8 GHz (1-sigma).
The Australia Telescope Compact Array (/ Parkes telescope / Mopra telescope / Long Baseline Array) is part of the Australia Telescope which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO.
See field image at:
http://cira.ivec.org/dokuwiki/doku.php/grb/grb_080523_field_image

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Jochen Greiner, last update: 07-Nov-2008 [Disclaimer]