Gamma-ray Burst 110530A

(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 30 May 11 15:31:59 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     454473,   Seg_Num: 0
GRB_RA:          282.045d {+18h 48m 11s} (J2000),
                 282.075d {+18h 48m 18s} (current),
                 281.914d {+18h 47m 39s} (1950)
GRB_DEC:         +61.932d {+61d 55' 54"} (J2000),
                 +61.945d {+61d 56' 42"} (current),
                 +61.874d {+61d 52' 26"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       28845 [cnts]    Image_Peak=658 [image_cnts]
TRIGGER_DUR:     8.192 [sec] 
TRIGGER_INDEX:   453     E_range: 15-50 keV
BKG_INTEN:       205232 [cnts]
BKG_TIME:        55768.99 SOD {15:29:28.99} UT
BKG_DUR:         64 [sec]
GRB_DATE:        15711 TJD;   150 DOY;   11/05/30
GRB_TIME:        55862.68 SOD {15:31:02.68} UT
GRB_PHI:         -38.39 [deg]
GRB_THETA:        15.96 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.66 [sigma]
IMAGE_SIGNIF:    9.75 [sigma]
MERIT_PARAMS:     +1  +0  +0  +3  +1  +0  +0  +0  +3  +0 
SUN_POSTN:        67.18d {+04h 28m 42s}  +21.78d {+21d 46' 48"}
SUN_DIST:         91.76 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.83d {+02h 39m 20s}  +19.15d {+19d 08' 49"}
MOON_DIST:        85.27 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.91, 24.10 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.05, 83.03 [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 = 110.13,-18.94 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:34:49 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     454473,   Seg_Num: 0
GRB_RA:          282.045d {+18h 48m 11s} (J2000),
                 282.075d {+18h 48m 18s} (current),
                 281.914d {+18h 47m 39s} (1950)
GRB_DEC:         +61.932d {+61d 55' 54"} (J2000),
                 +61.945d {+61d 56' 42"} (current),
                 +61.874d {+61d 52' 26"} (1950)
GRB_DATE:        15711 TJD;   150 DOY;   11/05/30
GRB_TIME:        55862.68 SOD {15:31:02.68} UT
TRIGGER_INDEX:   453
GRB_PHI:         -38.39 [deg]
GRB_THETA:        15.96 [deg]
DELTA_TIME:      71.00 [sec]
TRIGGER_DUR:     8.192 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.66 [sigma]
IMAGE_SIGNIF:    9.75 [sigma]
LC_URL:          sw00454473000msb.lc
SUN_POSTN:        67.18d {+04h 28m 43s}  +21.78d {+21d 46' 49"}
SUN_DIST:         91.76 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.86d {+02h 39m 26s}  +19.15d {+19d 09' 10"}
MOON_DIST:        85.27 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.91, 24.10 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.05, 83.03 [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 = 110.13,-18.94 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:41:03 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.036d {+18h 48m 09s} (J2000)
POINT_DEC:       +61.930d {+61d 55' 47"} (J2000)
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56296.70 SOD {15:38:16.70} UT,   434.0 [sec] since BAT Trigger Time
COUNTS:          2    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        1    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:43:45 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.036d {+18h 48m 09s} (J2000)
POINT_DEC:       +61.930d {+61d 55' 47"} (J2000)
POINT_ROLL:      32.071d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56300.18 SOD {15:38:20.18} UT,   437.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.559
N_STARS:         188
X_OFFSET:        533 [pixels]
Y_OFFSET:        562 [pixels]
X_MAX:           1492 [pixels]
Y_MAX:           1521 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00454473000msufc0437.fits
SUN_POSTN:        67.18d {+04h 28m 44s}  +21.78d {+21d 46' 52"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.94d {+02h 39m 44s}  +19.17d {+19d 10' 15"}
MOON_DIST:        85.29 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      324.02, 83.04 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:44:18 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.036d {+18h 48m 09s} (J2000)
POINT_DEC:       +61.930d {+61d 55' 47"} (J2000)
POINT_ROLL:      32.071d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56300.18 SOD {15:38:20.18} UT,   437.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.559
N_STARS:         188
X_OFFSET:        533 [pixels]
Y_OFFSET:        562 [pixels]
X_MAX:           1492 [pixels]
Y_MAX:           1521 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00454473000msufc0437.fits
SUN_POSTN:        67.19d {+04h 28m 44s}  +21.78d {+21d 46' 53"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.94d {+02h 39m 46s}  +19.17d {+19d 10' 19"}
MOON_DIST:        85.29 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      324.02, 83.04 [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 30 May 11 15:44:58 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     454473,   Seg_Num: 0
GRB_RA:          282.0671d {+18h 48m 16.10s} (J2000),
                 282.0968d {+18h 48m 23.22s} (current),
                 281.9366d {+18h 47m 44.77s} (1950)
GRB_DEC:         +61.9286d {+61d 55' 42.9"} (J2000),
                 +61.9419d {+61d 56' 30.8"} (current),
                 +61.8707d {+61d 52' 14.5"} (1950)
GRB_ERROR:       3.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56314.00 SOD {15:38:34.00} UT,   451.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        67.19d {+04h 28m 45s}  +21.78d {+21d 46' 53"}
SUN_DIST:         91.76 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.95d {+02h 39m 47s}  +19.17d {+19d 10' 24"}
MOON_DIST:        85.28 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.91, 24.09 [deg] galactic lon,lat of the burst
ECL_COORDS:      324.10, 83.02 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:45:13 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.036d {+18h 48m 09s} (J2000)
POINT_DEC:       +61.930d {+61d 55' 47"} (J2000)
ROLL:            32.071d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56300.18 SOD {15:38:20.18} UT,   437.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     328462707
X_OFFSET:        852 [pixels]
Y_OFFSET:        881 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1012
Y_GRB_POS:       1041
BINNING_INDEX:   1
IM_URL:          sw00454473000msuni0445.fits
SUN_POSTN:        67.19d {+04h 28m 45s}  +21.78d {+21d 46' 53"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.95d {+02h 39m 48s}  +19.17d {+19d 10' 26"}
MOON_DIST:        85.29 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      324.02, 83.04 [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 30 May 11 15:45:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.036d {+18h 48m 09s} (J2000)
POINT_DEC:       +61.930d {+61d 55' 47"} (J2000)
ROLL:            32.071d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56300.18 SOD {15:38:20.18} UT,   437.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     328462707
X_OFFSET:        852 [pixels]
Y_OFFSET:        881 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1012
Y_GRB_POS:       1041
BINNING_INDEX:   1
IM_URL:          sw00454473000msuni0445.fits
SUN_POSTN:        67.19d {+04h 28m 45s}  +21.78d {+21d 46' 53"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.95d {+02h 39m 48s}  +19.17d {+19d 10' 28"}
MOON_DIST:        85.29 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      324.02, 83.04 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:47:17 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     454473,   Seg_Num: 0
GRB_RA:          282.0681d {+18h 48m 16.34s} (J2000),
                 282.0978d {+18h 48m 23.46s} (current),
                 281.9376d {+18h 47m 45.02s} (1950)
GRB_DEC:         +61.9292d {+61d 55' 45.1"} (J2000),
                 +61.9425d {+61d 56' 32.9"} (current),
                 +61.8713d {+61d 52' 16.6"} (1950)
GRB_ERROR:       0.7 [arcsec radius, statistical only]
GRB_MAG:         20.30 +/- 0.17 [mag]
FILTER:          10, White
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56300.00 SOD {15:38:20.00} UT,   437.3 [sec] since BAT Trigger Time
SUN_POSTN:        67.19d {+04h 28m 45s}  +21.78d {+21d 46' 54"}
SUN_DIST:         91.76 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       39.97d {+02h 39m 52s}  +19.18d {+19d 10' 41"}
MOON_DIST:        85.28 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.91, 24.09 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      324.10, 83.02 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN Circular #12046
P. D'Avanzo (INAF-OAB), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), S. Campana (INAF-OAB), V. D'Elia (ASDC), J. M. Gelbord (PSU), B. Gendre (ASDC), C. Gronwall (PSU), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), V. Mangano (INAF-IASFPA), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), P. T. O\'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU), C. A. Swenson (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 15:31:02 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110530A (trigger=454473). Swift slewed after 11 minutes because of an observing constraint. The BAT on-board calculated location is RA, Dec 282.045, +61.932, which is
```
   RA(J2000)  =  18h 48m 11s
   Dec(J2000) = +61d 55' 54"
```
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 20 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~2 sec after the trigger.
The XRT began observing the field at 15:38:16.7 UT, 434.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 282.06718, 61.92861 which is equivalent to:
```
   RA(J2000)  = 18h 48m 16.12s
   Dec(J2000) = +61d 55' 43.0"
```
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This location is 39 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 5.65 x 10^20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 437 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	18:48:16.35 = 282.06814
  DEC(J2000) = +61:55:45.1  =  61.92920
```
with a 90%-confidence error radius of about 0.71 arc sec. This position is 2.8 arc sec. from the center of the XRT error circle. The estimated magnitude is 20.31 with a 1-sigma error of about 0.18. No correction has been made for the expected extinction corresponding to E(B-V) of 0.06.
Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:51:11 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.029d {+18h 48m 07s} (J2000)
POINT_DEC:       +61.929d {+61d 55' 43"} (J2000)
POINT_ROLL:      32.068d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56727.56 SOD {15:45:27.56} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.549
N_STARS:         190
X_OFFSET:        293 [pixels]
Y_OFFSET:        322 [pixels]
X_MAX:           1732 [pixels]
Y_MAX:           1761 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00454473000msufc0864.fits
SUN_POSTN:        67.19d {+04h 28m 46s}  +21.78d {+21d 46' 55"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       40.00d {+02h 40m 00s}  +19.19d {+19d 11' 10"}
MOON_DIST:        85.30 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.99, 83.04 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:51:41 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.029d {+18h 48m 07s} (J2000)
POINT_DEC:       +61.929d {+61d 55' 43"} (J2000)
POINT_ROLL:      32.068d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56727.56 SOD {15:45:27.56} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.549
N_STARS:         190
X_OFFSET:        293 [pixels]
Y_OFFSET:        322 [pixels]
X_MAX:           1732 [pixels]
Y_MAX:           1761 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00454473000msufc0864.fits
SUN_POSTN:        67.19d {+04h 28m 46s}  +21.78d {+21d 46' 55"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       40.00d {+02h 40m 01s}  +19.19d {+19d 11' 13"}
MOON_DIST:        85.31 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.99, 83.04 [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 30 May 11 15:52:24 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.029d {+18h 48m 07s} (J2000)
POINT_DEC:       +61.929d {+61d 55' 43"} (J2000)
ROLL:            32.068d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56727.56 SOD {15:45:27.56} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     328463134
X_OFFSET:        852 [pixels]
Y_OFFSET:        881 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1012
Y_GRB_POS:       1041
BINNING_INDEX:   1
IM_URL:          sw00454473000msuni0872.fits
SUN_POSTN:        67.19d {+04h 28m 46s}  +21.78d {+21d 46' 56"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       40.01d {+02h 40m 03s}  +19.19d {+19d 11' 19"}
MOON_DIST:        85.31 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.99, 83.04 [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 30 May 11 15:52:40 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     454473,   Seg_Num: 0
POINT_RA:        282.029d {+18h 48m 07s} (J2000)
POINT_DEC:       +61.929d {+61d 55' 43"} (J2000)
ROLL:            32.068d
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56727.56 SOD {15:45:27.56} UT,   864.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     328463134
X_OFFSET:        852 [pixels]
Y_OFFSET:        881 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1012
Y_GRB_POS:       1041
BINNING_INDEX:   1
IM_URL:          sw00454473000msuni0872.fits
SUN_POSTN:        67.19d {+04h 28m 46s}  +21.78d {+21d 46' 56"}
SUN_DIST:         91.77 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       40.01d {+02h 40m 03s}  +19.19d {+19d 11' 21"}
MOON_DIST:        85.31 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.90, 24.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.99, 83.04 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 30 May 11 15:52:58 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     454473,   Seg_Num: 0
GRB_RA:          282.0692d {+18h 48m 16.60s} (J2000),
                 282.0989d {+18h 48m 23.73s} (current),
                 281.9387d {+18h 47m 45.28s} (1950)
GRB_DEC:         +61.9286d {+61d 55' 42.9"} (J2000),
                 +61.9419d {+61d 56' 30.8"} (current),
                 +61.8707d {+61d 52' 14.5"} (1950)
GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15711 TJD;   150 DOY;   11/05/30
IMG_START_TIME:  56314.00 SOD {15:38:34.00} UT,   451.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        67.19d {+04h 28m 46s}  +21.78d {+21d 46' 56"}
SUN_DIST:         91.76 [deg]   Sun_angle= 9.7 [hr] (West of Sun)
MOON_POSTN:       40.02d {+02h 40m 04s}  +19.19d {+19d 11' 23"}
MOON_DIST:        85.29 [deg]
MOON_ILLUM:      5 [%]
GAL_COORDS:       91.91, 24.09 [deg] galactic lon,lat of the burst
ECL_COORDS:      324.10, 83.02 [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 Circular #12048
Y. Yatsu, K.Kawakami, Y. Aoki, K. Tokoyoda, M. Hayashi, S. Song, R. Usui, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed GRB110530A (D'Avanzo et al, GCN12046) with the optical three color (g, Rc, and Ic) CCD camera attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan. The follow-up observation was started at 15:31:02, ~2min after the BAT trigger. And we detected a very faint object within the XRT error circle in R-band. The measured R-band magnitude is shown below.
```
T0+[s]   MID-UT   T-EXP[sec]    g'             Rc           Ic
-----------------------------------------------------------------------
125    15:39:42          660           ---   18.84 +/- 0.65   ---
-----------------------------------------------------------------------
T0+ : Elapsed time after the burst [sec]
T-EXP: Total Exposure time [sec]
```
Photometric results and are listed below. We used GSC2.3 catalog for flux calibration.
GCN Circular #12049
W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), P. D'Avanzo (INAF-OAB), 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-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 110530A (trigger #454473) (D'Avanzo, et al., GCN Circ. 12046). The BAT ground-calculated position is RA, Dec = 282.045, 61.953 deg, which is
```
   RA(J2000)  =  18h 48m 10.8s 
   Dec(J2000) = +61d 57' 11.2" 
```
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 98%.
The mask-weighted light curve shows a single pulse starting at ~T-50 sec with a slow rise, peaking at ~T+2 sec, and ending at ~T+15 sec. T90 (15-350 keV) is 19.6 +- 3.1 sec (estimated error including systematics).
The time-averaged spectrum from T-4.5 to T+17.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.06 +- 0.24. The fluence in the 15-150 keV band is 3.3 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+1.01 sec in the 15-150 keV band is 0.4 +- 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/454473/BA/
GCN Circular #12050
K.Ivanov, O. Gres, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Chuvalaev 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, A. Popov Ural State University, Kourovka
A. Tlatov, A.V. Parhomenko, D. Dormidontov,V. Senik Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, 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 GRB 110530A (D'Avanzo et al, GCN12046) 12 sec s after notice time and 73 sec after GRB time at 2011-05-30 15:32:15.215 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 15.2 mag (Polarization + R band).
The OT appears at 15:42:14 UT (t_start-t_triger = 673 s, Exp_time=130s). Mag ~18.3 (R).
After that we see OT on our images in different filters (R,I,Unfiltered,R+P). 20 min ago (2011-05-30 17:44:42): R ~19.5+-0.5.
The reduction is continued.
This message may be cited.
GCN Circular #12051
Vladimir Lipunov.
The GCN Circular N 12050 correct subject is:
GRB 110530A: MASTER OT observations
I am sorry.
GCN Circular #12052
M. Andreev, A. Sergeev, I. Sokolov (Terskol Branch of Institute of Astronomy), Yu. Bronich (IC AMER of NASU), A.Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the optical afterglow of the Swift GRB 110530A (D'Avanzo et al, GCN 12046) with Zeiss-2000 and Zeiss-600 telescopes of Mt.Terskol observatory. Optical afterglow is detected in a stacked images. The photometry is based on the star USNO-B1.0 1519-0265568 (RA=18 48 15.86, Dec=+61 56 15.0) assuming R=16.08 is following
```
UT (mid time), Exposure,   Filter,     OT

18:00              12 x 30 s    R(gunn)  20.32 +/- 0.08
18:58              24 x 150 s  R           20.6   +/- 0.2 
```
GCN Circular #12053
D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (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 110530A (D'Avanzo et al., GCNC 12046) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2011-05-30 15:41:32 UT (~11 min after the burst). We detected the previously reported afterglow (Yatsu et al., GCNC 12048) in Rc and Ic bands.
Photometric results and are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'    Rc  Rc_err   Ic  Ic_err
----------------------------------------------------------------------
0.06460    17:04:03    5520.0   >20.3  19.8   0.2   19.6   0.2
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #12054
A. De Cia, P. Vreeswijk (U. of Iceland), D. Xu (Weizmann Inst.), J. Telting (NOT) and P. Jakobsson (U. of Iceland)
report on behalf of a larger collaboration:
We observed the field of D'Avanzo et al. (GCN 12046) with the 2.5m NOT telescope at Roque de los Muchachos Observatory (La Palma, Spain) equipped with ALFOSC, starting at 22:18 UT (6.8h after the burst). The optical afterglow is detected, within the XRT error circle reported by D'Avanzo et al., at R ~ 21.3, calibrated against the USNO-B1.0 1519-0265568 star (R2=16.08) also adopted by Andreev et al. GCN 12052.
Preliminary reduction of the subsequent spectroscopic observations does not show any evident absorption lines, given the poor S/N. A rough limit on the source redshift z<2.7 may be placed by the non-detection of Lyman alpha absorption in the spectra.
GCN Circular #12055
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 8011 s of XRT Photon Counting mode data and 7 UVOT images for GRB 110530A, 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 = 282.06843, +61.92897 which is equivalent to:
```
RA (J2000): 18h 48m 16.42s
Dec (J2000): +61d 55' 44.3"
```
with an uncertainty of 1.4 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 #12056
L.P. Xin, Y.L. Qiu, J.Y. Wei, J. Wang, J.S. Deng, C. Wu, X. H. Han on behalf of EAFON report:
We began to observe GRB 110530A (D'Avanzo et al, GCN 12046) with Xinglong TNT telescope at 15:33:15(UT), 133 sec after the burst. The optical afterglow is clearly detected in all images. The brightness is 20.7 mag in R band relative to the reference star of Andreev et al. (GCN Circ. 12052) at the mean time of 10000 sec after the burst.
More observations are encouraged.
This message may be cited.
GCN Circular #12057
F. E. Marshall (NASA/GSFC) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 110530A 438 s after the BAT trigger (D'Avanzo et al., GCN Circ. 12046). A fading source consistent with the enhanced XRT position (Evans et al., GCN Circ. 12055) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
    RA  (J2000) =  18:48:16.40 = 282.06833 (deg.)
    Dec (J2000) = +61:55:44.9  =  61.92913 (deg.)
```
with an estimated uncertainty of 0.65 arc sec. (radius, 90% confidence).
Preliminary detections 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              438         1015          295         20.31 +/- 0.10
white             7070         8315         1042         21.52 +/- 0.21
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.06 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12058
P. D'Avanzo (INAF-OAB) reports on behalf of the Swift-XRT team:
We have analysed 12 ks of XRT data for GRB 110530A (D'Avanzo et al. GCN Circ. 12046), from 446 s to 43.1 ks after the BAT trigger. The data comprise 29 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 12055).
The light curve can be modelled with a power-law decay with a decay index of alpha=0.81 (+0.05, -0.04).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.30 (+0.09, -0.17). The best-fitting absorption column is 2.8 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 5.6 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (7.0 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     2.8 (+/-0.5) x 10^21 cm^-2
Galactic foreground: 5.6 x 10^20 cm^-2
Excess significance: 9.2 sigma
Photon index:	     2.30 (+0.09, -0.17)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00454473.
This circular is an official product of the Swift-XRT team.
GCN Circular #12059
M. Andreev, A. Sergeev, I. Sokolov (Terskol Branch of Institute of Astronomy), Yu. Bronich (IC AMER of NASU), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the optical afterglow of the Swift GRB 110530A (D'Avanzo et al, GCN 12046) with Zeiss-2000 telescope of Mt.Terskol observatory On May, 31 between (UT) 21:41-22:11. At the place of optical afterglow we detect extended object (elongated from SE to NW) with brightness R(gunn) ~ 22.7 calibrated against the star USNO-B1.0 1519-0265568 (RA=18 48 15.86, Dec=+61 56 15.0) and assuming R=16.08.
Coordinates of South-East part of the extended object are (J2000) 18 48 16.27 +61 55 45.3 which is ~2" apart from position of the optical afterglow (J2000) 18 48 16.39 +61 55 45.16 obtained in our first epoch observations (Andreev et al. GCN 12052). The accuracy of astrometry is about 0.7" in both coordinates. One can suggest the extended object might be a bright host of GRB 110530A. The finding chart can be found at http://grb.rssi.ru/GRB110530A/grb110530_2m110531.jpg
GCN Circular #12062
A. Volnova (SAI MSU), E. Klunko (ISTP), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the optical afterglow of the Swift GRB 110530A (D'Avanzo et al, GCN 12046) with AZT-33IK telescope of Sayan observatory (Mondy) on May, 30 between (UT) 16:06:01 - 19:14:06 (i.e. t0+0.0243 d -- t0+0.1549 days after burst trigger). We took several series of 60 s exposures in R. Optical afterglow is detected in single images in the beginning of the observations while in the end we stacked images in 180 - 300 s combined exposures. The photometry is based on the USNO-B1.0 1519-0265568 star (RA=18 48 15.86, Dec=+61 56 15.0) assuming R=16.08. In particular, the photometry
```
UT (mid time), Exposure,   Filter,     OT
18:04               5x60          R           20.25 +/- 0.06
18:54               5x60          R           20.58 +/- 0.07
```
coincide with the photometry reported earlier (Andreev et al., GCN 12052).
Preliminary light curve can be found at
http://grb.rssi.ru/GRB110530A/GRB110530A_AZT33IK_lc.png
One can note a non-monotonous light curve decay with possible rebrightening at 0.03 d and 0.53 d and general power law decay index of about 0.9.
GCN Report 337.1
GCN_Report 337.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_337_1.pdf by P. D Avanzo at INAF-OAB titled: "Final Report on Swift GRB 110530A"
1305.1620 from 9 May 13
E. S. Gorbovskoy et al.: The MASTER-II Network of Robotic Optical Telescopes. First Results
The main stages in the creation of the Russian segment of the MASTER network of robotic telescopes is described. This network is designed for studies of the prompt optical emission of gamma- ray bursts (GRBs; optical emission synchronous with the gamma-ray radiation) and surveys of the sky aimed at discovering uncataloged objects and photometric studies for various programs. The first results obtained by the network, during its construction and immediately after its completion in December 2010, are presented. Eighty-nine alert pointings at GRBs (in most cases, being the first ground telescopes to point at the GRBs) were made from September 2006 through July 2011. The MASTER network holds first place in the world in terms of the total number of first pointings, and currently more than half of first pointings at GRBs by ground telescopes are made by the MASTER network. Photometric light curves of GRB 091020, GRB 091127, GRB 100901A, GRB 100906A, GRB 10925A, GRB 110106A, GRB 110422A, and GRB 110530A are presented. It is especially important that prompt emission was observed for GRB 100901A and GRB 100906A, and thar GRB 091127, GRB 110422A, and GRB 110106A were observed from the first seconds in two polarizations. Very-wide-field cameras carried out synchronous observations of the prompt emission of GRB 081102, GRB 081130B, GRB 090305B, GRB 090320B, GRB 090328, and GRB 090424. Discoveries of Type Ia supernovae are ongoing (among them the brightest supernova in 2009): 2008gy, 2009nr, 2010V, and others. In all, photometry of 387 supernovae has been carried out, 43 of which were either discovered or first observed with MASTER telescopes; more than half of these are Type Ia supernovae. Photometric studies of the open clusters NGC 7129 and NGC 7142 have been conducted, leading to the discovery of 38 variable stars.
1607.08454 from 29 Jul 16
Shu-Qing Zhong et al.: GRB 110530A: Peculiar Broad Bump and Delayed Plateau in Early Optical Afterglows
We report our very early optical observations of GRB 110530A and investigate its jet properties together with its X-ray afterglow data. A peculiar broad onset bump followed by a plateau is observed in its early R band afterglow lightcurve. The optical data in the other bands and the X-ray data are well consistent with the temporal feature of the R band lightcurve. Our joint spectral fits of the optical and X-ray data show that they are in the same regime, with a photon index of $\sim 1.70$. The optical and X-ray afterglow lightcurves are well fitted with the standard external shock model by considering a delayed energy injection component. Based on our modeling results, we find that the radiative efficiency of the GRB jet is $\sim 1\%$ and the magnetization parameter of the afterglow jet is $<0.04$ with the derived extremely low $\epsilon_B$ (the fraction of shock energy to magnetic field) of $(1.64\pm 0.25)\times 10^{-6}$. These results indicate that the jet may be matter dominated. Discussion on delayed energy injection from accretion of late fall-back material of its pre-supernova star is also presented.

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