Gamma-ray Burst 110801A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:50:33 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.285d {+05h 57m 08s} (J2000),
                  89.840d {+05h 59m 22s} (current),
                  86.891d {+05h 47m 34s} (1950)
GRB_DEC:         +80.988d {+80d 59' 18"} (J2000),
                 +80.989d {+80d 59' 20"} (current),
                 +80.979d {+80d 58' 45"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       14033 [cnts]    Image_Peak=350 [image_cnts]
TRIGGER_DUR:     4.096 [sec] 
TRIGGER_INDEX:   298     E_range: 25-100 keV
BKG_INTEN:       119582 [cnts]
BKG_TIME:        71328.78 SOD {19:48:48.78} UT
BKG_DUR:         40 [sec]
GRB_DATE:        15774 TJD;   213 DOY;   11/08/01
GRB_TIME:        71382.99 SOD {19:49:42.99} UT
GRB_PHI:         -132.13 [deg]
GRB_THETA:        25.30 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.83 [sigma]
IMAGE_SIGNIF:    7.83 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  -2  +0  +0 -41  +0 
SUN_POSTN:       131.65d {+08h 46m 37s}  +17.95d {+17d 56' 52"}
SUN_DIST:         65.46 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.68d {+10h 26m 44s}   +4.49d {+04d 29' 22"}
MOON_DIST:        82.03 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.58, 24.69 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       89.79, 57.55 [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 = 147.48,16.92 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:51:58 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.4307d {+05h 57m 43.36s} (J2000),
                  89.9842d {+05h 59m 56.19s} (current),
                  87.0430d {+05h 48m 10.32s} (1950)
GRB_DEC:         +80.9548d {+80d 57' 17.2"} (J2000),
                 +80.9551d {+80d 57' 18.4"} (current),
                 +80.9462d {+80d 56' 46.4"} (1950)
GRB_ERROR:       4.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       3.54e-09 [erg/cm2/sec]
GRB_SIGNIF:      10.63 [sigma]
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71481.87 SOD {19:51:21.87} UT,   98.9 [sec] since BAT Trigger Time
TAM[0-3]:        327.64 237.21 261.47 243.56
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       131.66d {+08h 46m 37s}  +17.95d {+17d 56' 51"}
SUN_DIST:         65.42 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.70d {+10h 26m 47s}   +4.48d {+04d 29' 02"}
MOON_DIST:        82.00 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.62, 24.70 [deg] galactic lon,lat of the burst
ECL_COORDS:       89.83, 57.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.44 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:54:26 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.220d {+05h 56m 53s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.138d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71491.97 SOD {19:51:31.97} UT,   109.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.628
N_STARS:         158
X_OFFSET:        868 [pixels]
Y_OFFSET:        398 [pixels]
X_MAX:           1827 [pixels]
Y_MAX:           1357 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00458521000msufc0108.fits
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 49"}
SUN_DIST:         65.47 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.72d {+10h 26m 53s}   +4.47d {+04d 28' 27"}
MOON_DIST:        82.06 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:52:08 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.4307d {+05h 57m 43.3s} (J2000),
                  89.9842d {+05h 59m 56.1s} (current),
                  87.0430d {+05h 48m 10.3s} (1950)
GRB_DEC:         +80.9548d {+80d 57' 17.2"} (J2000),
                 +80.9551d {+80d 57' 18.4"} (current),
                 +80.9462d {+80d 56' 46.4"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       113 [cnts]
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71481.87 SOD {19:51:21.87} UT,   98.9 [sec] since BAT Trigger Time
CENTROID_X:      217.10,  raw= 217  [pixels]
CENTROID_Y:      284.35,  raw= 284  [pixels]
ROLL:            135.13 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -32.16
GRB_POS_XRT_Z:   -204.13
IMAGE_URL:       sw00458521000msxps_rw.img
SUN_POSTN:       131.66d {+08h 46m 37s}  +17.95d {+17d 56' 51"}
SUN_DIST:         65.42 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.70d {+10h 26m 47s}   +4.48d {+04d 29' 00"}
MOON_DIST:        82.00 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.62, 24.70 [deg] galactic lon,lat of the burst
ECL_COORDS:       89.83, 57.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:53:37 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.285d {+05h 57m 08s} (J2000),
                  89.840d {+05h 59m 22s} (current),
                  86.891d {+05h 47m 34s} (1950)
GRB_DEC:         +80.988d {+80d 59' 18"} (J2000),
                 +80.989d {+80d 59' 20"} (current),
                 +80.979d {+80d 58' 45"} (1950)
GRB_DATE:        15774 TJD;   213 DOY;   11/08/01
GRB_TIME:        71382.99 SOD {19:49:42.99} UT
TRIGGER_INDEX:   298
GRB_PHI:         -132.13 [deg]
GRB_THETA:        25.30 [deg]
DELTA_TIME:      19.00 [sec]
TRIGGER_DUR:     4.096 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     8.83 [sigma]
IMAGE_SIGNIF:    7.83 [sigma]
LC_URL:          sw00458521000msb.lc
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 50"}
SUN_DIST:         65.46 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.71d {+10h 26m 51s}   +4.48d {+04d 28' 39"}
MOON_DIST:        82.04 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.58, 24.69 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       89.79, 57.55 [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 = 147.48,16.92 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:52:16 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.4307d {+05h 57m 43.3s} (J2000),
                  89.9842d {+05h 59m 56.1s} (current),
                  87.0430d {+05h 48m 10.3s} (1950)
GRB_DEC:         +80.9548d {+80d 57' 17.2"} (J2000),
                 +80.9551d {+80d 57' 18.4"} (current),
                 +80.9462d {+80d 56' 46.4"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       113 [cnts]
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71481.87 SOD {19:51:21.87} UT,   98.9 [sec] since BAT Trigger Time
CENTROID_X:      217.10,  raw= 217  [pixels]
CENTROID_Y:      284.35,  raw= 284  [pixels]
ROLL:            135.13 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -32.16
GRB_POS_XRT_Z:   -204.13
IMAGE_URL:       sw00458521000msxps_rw.img
SUN_POSTN:       131.66d {+08h 46m 37s}  +17.95d {+17d 56' 50"}
SUN_DIST:         65.42 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.70d {+10h 26m 48s}   +4.48d {+04d 28' 58"}
MOON_DIST:        82.00 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.62, 24.70 [deg] galactic lon,lat of the burst
ECL_COORDS:       89.83, 57.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:56:21 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.220d {+05h 56m 53s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.138d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71491.97 SOD {19:51:31.97} UT,   109.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     333921099
X_OFFSET:        1188 [pixels]
Y_OFFSET:        718 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1348
Y_GRB_POS:       878
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0116.fits
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 48"}
SUN_DIST:         65.47 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.74d {+10h 26m 57s}   +4.47d {+04d 28' 00"}
MOON_DIST:        82.07 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:54:55 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.220d {+05h 56m 53s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.138d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71491.97 SOD {19:51:31.97} UT,   109.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.628
N_STARS:         158
X_OFFSET:        868 [pixels]
Y_OFFSET:        398 [pixels]
X_MAX:           1827 [pixels]
Y_MAX:           1357 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00458521000msufc0108.fits
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 49"}
SUN_DIST:         65.47 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.72d {+10h 26m 54s}   +4.47d {+04d 28' 21"}
MOON_DIST:        82.06 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 19:56:05 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.220d {+05h 56m 53s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.138d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71491.97 SOD {19:51:31.97} UT,   109.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     333921099
X_OFFSET:        1188 [pixels]
Y_OFFSET:        718 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1348
Y_GRB_POS:       878
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0116.fits
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 48"}
SUN_DIST:         65.47 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.73d {+10h 26m 56s}   +4.47d {+04d 28' 04"}
MOON_DIST:        82.07 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 19:58:40 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.4363d {+05h 57m 44.71s} (J2000),
                  89.9898d {+05h 59m 57.55s} (current),
                  87.0484d {+05h 48m 11.60s} (1950)
GRB_DEC:         +80.9560d {+80d 57' 21.6"} (J2000),
                 +80.9563d {+80d 57' 22.7"} (current),
                 +80.9475d {+80d 56' 50.8"} (1950)
GRB_ERROR:       0.6 [arcsec radius, statistical only]
GRB_MAG:         18.03 +/- 0.14 [mag]
FILTER:          10, White
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71491.00 SOD {19:51:31.00} UT,   108.0 [sec] since BAT Trigger Time
SUN_POSTN:       131.66d {+08h 46m 38s}  +17.95d {+17d 56' 46"}
SUN_DIST:         65.42 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.76d {+10h 27m 02s}   +4.46d {+04d 27' 27"}
MOON_DIST:        82.03 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.62, 24.70 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       89.84, 57.52 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The UVOT position is 5.0 arcsec from the XRT position.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:58:49 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.203d {+05h 56m 49s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.121d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71649.98 SOD {19:54:09.98} UT,   267.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.501
N_STARS:         57
X_OFFSET:        868 [pixels]
Y_OFFSET:        398 [pixels]
X_MAX:           1827 [pixels]
Y_MAX:           1357 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00458521000msufc0266.fits
SUN_POSTN:       131.66d {+08h 46m 39s}  +17.95d {+17d 56' 46"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.76d {+10h 27m 02s}   +4.46d {+04d 27' 25"}
MOON_DIST:        82.09 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 19:59:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.203d {+05h 56m 49s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.121d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71649.98 SOD {19:54:09.98} UT,   267.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.501
N_STARS:         57
X_OFFSET:        868 [pixels]
Y_OFFSET:        398 [pixels]
X_MAX:           1827 [pixels]
Y_MAX:           1357 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00458521000msufc0266.fits
SUN_POSTN:       131.66d {+08h 46m 39s}  +17.95d {+17d 56' 46"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.76d {+10h 27m 03s}   +4.46d {+04d 27' 21"}
MOON_DIST:        82.09 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 20:00:13 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.203d {+05h 56m 49s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.121d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71649.98 SOD {19:54:09.98} UT,   267.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     333921257
X_OFFSET:        1188 [pixels]
Y_OFFSET:        718 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1348
Y_GRB_POS:       878
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0274.fits
SUN_POSTN:       131.66d {+08h 46m 39s}  +17.95d {+17d 56' 45"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.77d {+10h 27m 05s}   +4.45d {+04d 27' 05"}
MOON_DIST:        82.09 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 20:00:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.203d {+05h 56m 49s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.121d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  71649.98 SOD {19:54:09.98} UT,   267.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     333921257
X_OFFSET:        1188 [pixels]
Y_OFFSET:        718 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1348
Y_GRB_POS:       878
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0274.fits
SUN_POSTN:       131.66d {+08h 46m 39s}  +17.95d {+17d 56' 45"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.77d {+10h 27m 06s}   +4.45d {+04d 27' 02"}
MOON_DIST:        82.10 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #12228
M. De Pasquale (UCL-MSSL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU), J. A. Kennea (PSU), A. Melandri (INAF-OAB), C. J. Mountford (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU), E. Sonbas (GSFC/USRA/Adiyaman Univ.), C. A. Swenson (PSU), E. Troja (NASA/GSFC/ORAU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 19:49:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110801A (trigger=458521). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 89.285, +80.988 which is
```
   RA(J2000)  =  05h 57m 08s
   Dec(J2000) = +80d 59' 18"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a few weak peaks with a duration of about 70 sec. The peak count rate was ~700 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 19:51:21.9 UT, 98.9 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 89.4307, +80.9548 which is equivalent to:
```
    RA(J2000)  = 05h 57m 43.36s
    Dec(J2000) = +80d 57' 17.2"
```
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This location is 146 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
UVOT took a finding chart exposure of 150 seconds with the White filter starting 108 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	05:57:44.73 =  89.43637
  DEC(J2000) = +80:57:21.6  =  80.95600
```
with a 90%-confidence error radius of about 0.62 arc sec. This position is 5.4 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.03 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.08.
Burst Advocate for this burst is M. De Pasquale (mdp AT mssl.ucl.ac.uk). 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:     Mon 01 Aug 11 20:08:09 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.201d {+05h 56m 48s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.120d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  72252.78 SOD {20:04:12.78} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.132
N_STARS:         190
X_OFFSET:        608 [pixels]
Y_OFFSET:        158 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           1597 [pixels]
DET_THRESH:      23
PHOTO_THRESH:    14
SL_URL:          sw00458521000msufc0869.fits
SUN_POSTN:       131.67d {+08h 46m 40s}  +17.94d {+17d 56' 40"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.85d {+10h 27m 23s}   +4.42d {+04d 25' 13"}
MOON_DIST:        82.14 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 20:08:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.201d {+05h 56m 48s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
POINT_ROLL:      135.120d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  72252.78 SOD {20:04:12.78} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        7.132
N_STARS:         190
X_OFFSET:        608 [pixels]
Y_OFFSET:        158 [pixels]
X_MAX:           2047 [pixels]
Y_MAX:           1597 [pixels]
DET_THRESH:      23
PHOTO_THRESH:    14
SL_URL:          sw00458521000msufc0869.fits
SUN_POSTN:       131.67d {+08h 46m 40s}  +17.94d {+17d 56' 40"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.85d {+10h 27m 24s}   +4.42d {+04d 25' 09"}
MOON_DIST:        82.14 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 20:09:02 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     458521,   Seg_Num: 0
GRB_RA:           89.4375d {+05h 57m 45.00s} (J2000),
                  89.9910d {+05h 59m 57.84s} (current),
                  87.0496d {+05h 48m 11.89s} (1950)
GRB_DEC:         +80.9560d {+80d 57' 21.6"} (J2000),
                 +80.9563d {+80d 57' 22.7"} (current),
                 +80.9475d {+80d 56' 50.8"} (1950)
GRB_ERROR:       2.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  72054.00 SOD {20:00:54.00} UT,   671.0 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       131.67d {+08h 46m 40s}  +17.94d {+17d 56' 40"}
SUN_DIST:         65.42 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.85d {+10h 27m 25s}   +4.42d {+04d 25' 00"}
MOON_DIST:        82.09 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.62, 24.70 [deg] galactic lon,lat of the burst
ECL_COORDS:       89.84, 57.52 [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 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Aug 11 20:09:48 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.201d {+05h 56m 48s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.120d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  72252.78 SOD {20:04:12.78} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     333921860
X_OFFSET:        1167 [pixels]
Y_OFFSET:        717 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1327
Y_GRB_POS:       877
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0877.fits
SUN_POSTN:       131.67d {+08h 46m 40s}  +17.94d {+17d 56' 39"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.86d {+10h 27m 27s}   +4.41d {+04d 24' 50"}
MOON_DIST:        82.14 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [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:     Mon 01 Aug 11 20:10:03 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     458521,   Seg_Num: 0
POINT_RA:         89.201d {+05h 56m 48s} (J2000)
POINT_DEC:       +81.001d {+81d 00' 04"} (J2000)
ROLL:            135.120d
IMG_START_DATE:  15774 TJD;   213 DOY;   11/08/01
IMG_START_TIME:  72252.78 SOD {20:04:12.78} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     333921860
X_OFFSET:        1167 [pixels]
Y_OFFSET:        717 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1327
Y_GRB_POS:       877
BINNING_INDEX:   1
IM_URL:          sw00458521000msuni0877.fits
SUN_POSTN:       131.67d {+08h 46m 40s}  +17.94d {+17d 56' 39"}
SUN_DIST:         65.48 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:      156.86d {+10h 27m 27s}   +4.41d {+04d 24' 46"}
MOON_DIST:        82.15 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.56, 24.68 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       89.77, 57.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #12229
GRB 110801A: ROTSE-III Detection of re-brightening from OT
W. Zheng (U Mich), T. Guver (U Arizona), report on behalf of the ROTSE collaboration:
ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, Turkey, responded to GRB 110801A (Swift trigger 458521; Pasquale et al. GCN 12228). The first image was at 19:52:57.7 UT, 194.7 s after the burst (8.7 s after the GCN notice time). The unfiltered images are calibrated relative to USNO A2.0. We detect the OT at UVOT location (GCN 12228), the OT appeared to be re-brightening to ~15.0 mag at ~1400s after the burst. Continuing observations are in progress.
GCN Circular #12230
GRB 110801A: TLS Optical afterglow Confirmation
A. Nicuesa Guelbenzu, X. Luo, S. Klose, U. Laux, B. Stecklum (all at TLS Tautenburg) report:
We observed the afterglow of GRB 110801A (M. De Pasquale et al., GCN 12228) with the 2m/1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg starting about 20 min after the GRB trigger.
The afterglow is clearly detected in the R band images at the position of the UVOT detection.
We confirm the re-brightening of the afterglow as reported by ROTSE III (Zheng et al. 2011, GCN 12229).
GCN Circular #12232
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1989 s of XRT Photon Counting mode data and 5 UVOT images for GRB 110801A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 89.43603, +80.95615 which is equivalent to:
```
RA (J2000): 05h 57m 44.65s
Dec (J2000): +80d 57' 22.2"
```
with an uncertainty of 1.8 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #12233
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ), K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 110801A (Pasquale et al., GCNC 12228) with the optical three color (g', Rc and Ic) CCD camera attached to the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory.
The observation started on 2011-08-01 19:53:51 UT (~4 min after the burst). We detected the previously reported afterglow (Pasquale et al., GCNC 12228; Zheng and Guver, GCNC 12229; Guelbenzu et al., GCNC 12230) in all the three bands.
Photometric results of the OT are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'  g'_err   Rc  Rc_err   Ic  Ic_err
----------------------------------------------------------------------
0.00323    19:54:21     60.0    16.16  0.07  15.14  0.04  14.44  0.04
0.00404    19:55:31     60.0    15.35  0.06  14.29  0.04  13.57  0.04
0.00485    19:56:41     60.0    15.38  0.06  14.28  0.04  13.56  0.04
0.00731    20:00:14     60.0    15.54  0.06  14.51  0.04  13.79  0.04
0.00976    20:03:45     60.0    15.71  0.07  14.67  0.04  13.98  0.04
0.01222    20:07:18     60.0    15.77  0.07  14.79  0.04  14.12  0.04
0.01466    20:10:48     60.0    15.89  0.07  14.91  0.04  14.24  0.04
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12234
A. Cabrera Lavers (GTC), A. de Ugarte Postigo (DARK/NBI), A.J. Castro-Tirado, J. Gorosabel, C.C. Thoene (IAA-CSIC), R. Dom=EDnguez (GTC) report on behalf of a larger collaboration:
We have observed the afterglow of GRB 110801A (De Pasquale et al. GCNC 12228) using OSIRIS at the 10.4m GTC telescope (La Palma, Spain). Observations consisted on 2x900s + 1x600s exposures using the R1000B grating (resolution ~1000) with coverage between 3600 and 7500 Angstrom. Observations started at 3:30 UT (7.7h after the burst). In a preliminary analysis, using archival calibrations, we detect a high signal to noise ratio continuum with absorption features that include CII, SiIV, SiII, CIV, FeII, AlII, AlIII, NiII, ZnII, and MnII, as well as fine structure FeII* and NiII* at a common redshift of z=1.858, which we identify as the redshift of the afterglow. We also identify two intervening systems at z=1.246 and z=0.745 through the presence of the MgII doublet.
GCN Circular #12235
A.P. Beardmore (U. Leicester) and M. De Pasquale (UCL-MSSL) report on behalf of the Swift-XRT team:
We have analysed 9.9 ks of XRT data for GRB 110801A (De Pasquale et al. GCN Circ. 12228), from 89 s to 24.0 ks after the BAT trigger. The data comprise 566 s in Windowed Timing (WT) mode (the first 7 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 12232).
The light curve initially shows a number of flares, the largest peaking at 500-600 count/s between T+355 s and T+390 s after the trigger. Once this flare has decayed, the light curve after T+800 s can be modelled by a power-law with a slope of 1.12 +/- 0.06.
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.754 (+0.025, -0.026). The best-fitting absorption column is 6.4 (+/-0.6) x 10^21 cm^-2, at a redshift of 1.858, in addition to the Galactic value of 6.2 x 10^20 cm^-2 (Kalberla et al. 2005). We note this spectrum includes strong spectral evolution through the flare. The PC mode spectrum has a photon index of 2.04 (+/-0.09) and a best-fitting absorption column of 1.6 (+1.6, -1.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Galactic foreground: 6.2 x 10^20 cm^-2
Intrinsic column:    1.6 (+1.6, -1.4) x 10^21 cm^-2 at z=1.858
Photon index:	     2.04 (+/-0.09)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00458521.
This circular is an official product of the Swift-XRT team.
GCN Circular #12236
M. De Pasquale (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 110801A 109 s after the BAT trigger (De Pasquale et al., GCN Circ. 12228). A source consistent with the XRT position (Evans et al., GCN Circ. 12232) is detected in the initial and summed UVOT exposures, except in um2=20 filter and a detection in uw2, at 2 sigma confidence level. Since the redshift of this event is 1.86 (Cabrera Lavers, GCN Circ. 12234), we think the weak detection in uw2 is due to flux in the reddest part of this filter.
The refined UVOT position is:
```
     RA  (J2000) =3D  05:57:44.87 =3D  89.43695 (deg.)
     Dec (J2000) =3D +80:57:21.1  =3D  80.95592 (deg.)
```
with an estimated uncertainty of 0.51 arc sec. (radius, 90% confidence).
The afterglow shows a quick rise from the first exposure up to ~300s.
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white (fc)         109        259          147         18.06 =B1 0.07
white              109       6337          727         17.23 =B1 0.05
v                  598       6747          451         17.07 =B1 0.06
b                  523       6132          432         17.47 =B1 0.05
u (fc)             267        517          246         15.89 =B1 0.05
u                  267       5927          488         15.68 =B1 0.04
w1                 647       5722          255         17.92 =B1 0.11
m2                 622       6904          404         >20.2
w2                 573       6543          452         20.48 =B1 0.41
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) =3D 0.08 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12237
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), M. De Pasquale (UCL-MSSL), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (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 110801A (trigger #458521) (De Pasquale, et al., GCN Circ. 12228). The BAT ground-calculated position is RA, Dec = 89.415, 80.958 deg, which is
```
   RA(J2000)  =  05h 57m 39.6s 
   Dec(J2000) = +80d 57' 28.5" 
```
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 78%.
The mask-weighted light curve shows two main clusters of peaks. The first starts at ~T-30 sec, with a maximum at ~T+2 sec, and a long exponental decay almost down to background before the second cluster. The second cluster starts ~T+310 sec, peaks at ~T+340 sec, and ending at ~T+550 sec. T90 (15-350 keV) is 385 +- 10 sec (estimated error including systematics).
The time-averaged spectrum from T-24.2 to T+385.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.84 +- 0.10. The fluence in the 15-150 keV band is 4.7 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+341.78 sec in the 15-150 keV band is 1.1 +- 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/458521/BA/
GCN Circular #12238
A.V. Parhomenko, A. Tlatov, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
K.Ivanov, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev,E.Konstantinov, Irkutsk State University
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov,A.Sankovich Sternberg Astronomical Institute, Moscow State University
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka(Siberia) was pointed to the GRB110801A 101 sec after GRB time at 2011-08-01 19:51:23 UT. Unfortunatelly the objects was not in focus because recently photometer modification. On our first (20s exposure) set we haven`t found optical transient within SWIFT error-box (De Pasquale et al., GCN 12228). The 3-sigma upper limit has been about 14.0 mag (white+polarizator).
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located near Kislovodsk (Caucasus Mountains) closed roof 20 min before trigger due to cloudy condidtions. The telescope was repointed to the GRB110901A only 47 min 40 sec after trigger time at 2011-08-01 20:37:22 UT. We found OT at UVOT postion (De Pasquale et al., GCN 12228). The results of our photometry are:
```
Time_Start    T_mean-T_trig  exp time       m        error      Band 
UT                  s          s 
20:37:22          2950        180         16.13       0.06        R
20:44:29          3377        180         16.12       0.06        R 
20:48:01          3589        180         16.29       0.08        R
20:48:01          3589        180         16.03       0.06     White 
20:51:24          3792        180         16.43       0.06        R
20:51:24          3792        180         16.19       0.06     White
23:20:14         12722        180         17.75       0.10        R
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.08 in the direction of the burst (Schlegel et al. 1998).
The power low index (F~t^-aplha) apha ~1.0+-0.1 during this observations in R-band.
The message may be cited.
GCN Circular #12239
A. Nicuesa Guelbenzu, S. Klose, S. Schmidl, A. Rossi, U. Laux, B. Stecklum (all at TLS Tautenburg) report:
We re-observed the afterglow of GRB 110801A (M. De Pasquale et al., GCN 12228) with the 2m/1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg starting about 24 hours after the GRB trigger.
A stacking of the first 15 minutes of the second epoch data does not show the afterglow in the R band down to 21 mag (Vega system). We conclude that a jet break has occurred within the last 24 hours.
GCN Circular #12240
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ), K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 110801A (De Pasquale et al., GCNC 12228) with the optical three color (g', Rc and Ic) CCD camera attached to the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory.
The observation started on 2011-08-02 17:38:02 UT (~21.8 h after the burst). We detected the previously reported afterglow (Pasquale et al., GCNC 12228; Zheng and Guver, GCNC 12229; Guelbenzu et al., GCNC 12230; Kuroda et al., GCNC 12233) in all the three bands.
Photometric results of the OT are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'  g'_err   Rc  Rc_err   Ic  Ic_err
----------------------------------------------------------------------
0.95038    18:38:15   5760.0     21.5  0.3    20.3  0.2   19.1   0.2
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12241
V. V. Sokolov, A. S. Moskvitin, T. A. Fatkhullun, (SAO RAS) report on behalf of a larger collaboration:
We observed the field of GRB 110801A (De Pasquale et al., GCN 12228) with the 6-m BTA of SAO RAS (Russia) equipped with the Scorpio. The observations were carried out in the B and Rc bands at 00:07:36 -- 00:13:36 UT, August, 02 (since 4.35 hours after the trigger). The weather conditions were tolerable, seeing around 2".5.
Magnitudes of optical transient are as follows:
```
B = 19.02 +/- 0.02
R = 18.10 +/- 0.01
```
Calibration were done against the magnitudes B2 = 16.74 and R2 = 15.73 of the USNO-B.1 star 1709-0023450 (R.A. = 05:57:24.91 Dec.= +80:57:39.8, Epoch = 2000). The magnitudes of OT were not corrected for the Galactic extinction E(B-V) = 0.08 in the direction of the burst (Schlegel et al. 1998).
Also we obtained 2 x 600 sec. spectrum (range = 4000 -- 8400A, resolution FWHM = 10A) at 00:19:54 -- 00:41:24 UT. At the noisy relatively blue continuum we marginally detected only the C IV absorption line corresponding to the red shift reported by Cabrera Lavers et al. (GCN 12234).
The message may be cited.
GCN Circular #12246
V. Rumyantsev (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the field of GRB 110801A (Pasquale et al. GCN 12228) with Shajn telescope of CrAO observatory on between Aug. 2 (UT) 22:03 and Aug. 3 (UT) 00:27 under variable weather conditions and a mean seeing of 2.1 arsces. We took several frames with exposure of 60 s in R-band. On a stacked image we detected the optical counterpart (Pasquale et al. GCN 12228, Zheng et al. GCN 12229). A photometry is based on the USNO B1.0 star 1709-0023450 (05 57 24.91 +80 57 39.8) assuming R=15.73.
```
T0+         Filter,   Exposure, mag.                  uplim (3 sigma)
(mid, d)               (s)

1.1428    R         74x60       21.60 +/- 0.09   23.2 
```
GCN Circular #12275
M. Andreev, N. Parakhin, A. Sergeev (Terskol Branch of Institute of Astronomy), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed field of the Swift GRB 110801A (Pasquale et al. GCN 12228) with Zeiss-600 telescope of Mt.Terskol observatory in R filter starting on Aug. 02 (UT) 00:25. In a stacked image we clearly detect optical afterglow (Pasquale et al. GCN 12228, Zheng et al. GCN 12229). A photometry is based on the USNO B1.0 star 1709-0023450 (05 57 24.91 +80 57 39.8) assuming R=15.73.
```
T0+         Filter,   Exposure, mag.
(mid, d)               (s)

0.1951   R         4x180       18.35 +/- 0.10
```
GCN Circular #12276
T. Sakamoto (GSFC/UMBC), 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), D. Palmer (LANL), M. Stamatikos (OSU), J. Tueller (GSFC), and T. Ukwatta (MSU)
V. Pal'shin, S. Golenetskii, R.Aptekar, E. Mazets, D. Frederiks, and T. Cline on behalf of the Konus-Wind team,
We performed the Konus-Wind and the Swift/BAT joint spectral analysis of GRB 110801A (Swift/BAT trigger #458521: De Pasquale et al., GCN Circ. 12228, Barthelmy et al. GCN Circ. 12237). Since the Konus-Wind observed this GRB in the waiting mode, we only have 3 channel spectral data for the Konus-Wind which cover the energy range from 20 keV to 1.2 MeV. The joint spectral analysis of the Konus-Wind and the Swift/BAT data allows us to derive the broad-band spectral parameters of this burst.
The time interval of the spectral data is chosen from T0(BAT)-26.43 to T0(BAT)+64.83 sec and from T0(BAT)+332.74 to T0(BAT)+388.67 sec where T0(BAT) is the trigger time of BAT at 19:49.43 UTC to include two time-separated episodes. The energy ranges which we used in the joint spectral analysis are 20-1200 keV and 14-150 keV for the Konus-Wind and the Swift/BAT respectively. The spectral data of two instruments are fitted with the spectral model multiplied by the constant factor to take into account the systematic effective area uncertainties in the response matrices of each instrument.
The spectrum is well fitted 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 10%. No systematic residual from the best fit model is seen in the spectral data of each instrument (see Sakamoto et al. 2011, PASJ, 63, 215 for the spectral cross-calibration). The best fit spectral parameters are: alpha = -1.70 (-0.15/+0.12) and Epeak = 140 (-60/+900) keV (chi2/dof = 74/58). The best fit spectral parameters for the GRB (Band) model fixing beta = -2.5 are: alpha = -1.70 (-0.15/+0.22), and Epeak = 140 (-50/+1270) keV (chi2/dof = 74/58). The energy fluence in the 15-1200 keV band calculated by a power-law with exponential cutoff model for this 147.2 sec interval is 7.3 (-0.9/+ 1.7)x10^-6 erg/cm2.
Assuming z=1.858 (Cabrera Lavers et al. GCN Circ. 12234) 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 = 1.0 (-0.2/+0.3) x10^53 erg in 1 keV to 10 MeV at the GRB rest frame extrapolating the best Band function fit fixing beta = -2.5.
All the quoted errors are at the 90% confidence level.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB110801A/
GCN Report 346.1
GCN_Report 346.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_346_1.pdf by M. De Pasquale at MSSL-UCL/UNLV titled: "Final Swift Observations of GRB 110801A"

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Jochen Greiner, last update: 15-Aug-2011 [Disclaimer]