Gamma-ray Burst 081128

(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 28 Nov 08 17:20:30 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.798d {+01h 23m 12s} (J2000),
                  20.926d {+01h 23m 42s} (current),
                  20.082d {+01h 20m 20s} (1950)
GRB_DEC:         +38.115d {+38d 06' 54"} (J2000),
                 +38.161d {+38d 09' 41"} (current),
                 +37.854d {+37d 51' 15"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=7714 [image_cnts]
TRIGGER_DUR:     88.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        14798 TJD;   333 DOY;   08/11/28
GRB_TIME:        62324.70 SOD {17:18:44.70} UT
GRB_PHI:         -179.99 [deg]
GRB_THETA:        31.95 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    20.22 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  +7  +0  +0 +75  +0 
SUN_POSTN:       245.02d {+16h 20m 05s}  -21.45d {-21d 27' 10"}
SUN_DIST:        138.72 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.53d {+17h 06m 07s}  -26.89d {-26d 53' 38"}
MOON_DIST:       132.51 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.78,-24.33 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       34.31, 27.08 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
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 = 67.82,-20.18 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:22:32 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.8061d {+01h 23m 13.46s} (J2000),
                  20.9341d {+01h 23m 44.19s} (current),
                  20.0896d {+01h 20m 21.50s} (1950)
GRB_DEC:         +38.1273d {+38d 07' 38.2"} (J2000),
                 +38.1736d {+38d 10' 25.1"} (current),
                 +37.8664d {+37d 51' 59.1"} (1950)
GRB_ERROR:       5.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       8.04e-10 [erg/cm2/sec]
GRB_SIGNIF:      6.16 [sigma]
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62522.20 SOD {17:22:02.20} UT,   197.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.26 261.49 243.62
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       245.02d {+16h 20m 05s}  -21.45d {-21d 27' 11"}
SUN_DIST:        138.73 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.55d {+17h 06m 11s}  -26.89d {-26d 53' 41"}
MOON_DIST:       132.50 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.79,-24.32 [deg] galactic lon,lat of the burst
ECL_COORDS:       34.32, 27.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.82 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:22:45 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.8061d {+01h 23m 13.4s} (J2000),
                  20.9341d {+01h 23m 44.1s} (current),
                  20.0896d {+01h 20m 21.5s} (1950)
GRB_DEC:         +38.1273d {+38d 07' 38.2"} (J2000),
                 +38.1736d {+38d 10' 25.1"} (current),
                 +37.8664d {+37d 51' 59.1"} (1950)
GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       38 [cnts]
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62522.20 SOD {17:22:02.20} UT,   197.5 [sec] since BAT Trigger Time
CENTROID_X:      370.30,  raw= 370  [pixels]
CENTROID_Y:      323.72,  raw= 324  [pixels]
ROLL:            280.79 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   60.64
GRB_POS_XRT_Z:   160.31
IMAGE_URL:       sw00335895000msxps_rw.img
SUN_POSTN:       245.02d {+16h 20m 05s}  -21.45d {-21d 27' 11"}
SUN_DIST:        138.73 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.55d {+17h 06m 12s}  -26.90d {-26d 53' 41"}
MOON_DIST:       132.50 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.79,-24.32 [deg] galactic lon,lat of the burst
ECL_COORDS:       34.32, 27.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:22:49 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.8061d {+01h 23m 13.4s} (J2000),
                  20.9341d {+01h 23m 44.1s} (current),
                  20.0896d {+01h 20m 21.5s} (1950)
GRB_DEC:         +38.1273d {+38d 07' 38.2"} (J2000),
                 +38.1736d {+38d 10' 25.1"} (current),
                 +37.8664d {+37d 51' 59.1"} (1950)
GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       38 [cnts]
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62522.20 SOD {17:22:02.20} UT,   197.5 [sec] since BAT Trigger Time
CENTROID_X:      370.30,  raw= 370  [pixels]
CENTROID_Y:      323.72,  raw= 324  [pixels]
ROLL:            280.79 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   60.64
GRB_POS_XRT_Z:   160.31
IMAGE_URL:       sw00335895000msxps_rw.img
SUN_POSTN:       245.02d {+16h 20m 05s}  -21.45d {-21d 27' 11"}
SUN_DIST:        138.73 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.55d {+17h 06m 12s}  -26.90d {-26d 53' 41"}
MOON_DIST:       132.50 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.79,-24.32 [deg] galactic lon,lat of the burst
ECL_COORDS:       34.32, 27.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:23:31 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.798d {+01h 23m 12s} (J2000),
                  20.926d {+01h 23m 42s} (current),
                  20.082d {+01h 20m 20s} (1950)
GRB_DEC:         +38.115d {+38d 06' 54"} (J2000),
                 +38.161d {+38d 09' 41"} (current),
                 +37.854d {+37d 51' 15"} (1950)
GRB_DATE:        14798 TJD;   333 DOY;   08/11/28
GRB_TIME:        62324.70 SOD {17:18:44.70} UT
TRIGGER_INDEX:   20000
GRB_PHI:         -179.99 [deg]
GRB_THETA:        31.95 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     88.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    20.22 [sigma]
LC_URL:          sw00335895000msb.lc
SUN_POSTN:       245.02d {+16h 20m 06s}  -21.45d {-21d 27' 12"}
SUN_DIST:        138.72 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.56d {+17h 06m 13s}  -26.90d {-26d 53' 42"}
MOON_DIST:       132.48 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.78,-24.33 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       34.31, 27.08 [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 an image 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 = 67.82,-20.18 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:25:14 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.754d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.152d {+38d 09' 07"} (J2000)
POINT_ROLL:      280.784d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62531.34 SOD {17:22:11.34} UT,   206.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.175
N_STARS:         82
X_OFFSET:        120 [pixels]
Y_OFFSET:        504 [pixels]
X_MAX:           1079 [pixels]
Y_MAX:           1463 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00335895000msufc0206.fits
SUN_POSTN:       245.02d {+16h 20m 06s}  -21.45d {-21d 27' 12"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.57d {+17h 06m 17s}  -26.90d {-26d 53' 44"}
MOON_DIST:       132.44 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:25:51 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.754d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.152d {+38d 09' 07"} (J2000)
POINT_ROLL:      280.784d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62531.34 SOD {17:22:11.34} UT,   206.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.175
N_STARS:         82
X_OFFSET:        120 [pixels]
Y_OFFSET:        504 [pixels]
X_MAX:           1079 [pixels]
Y_MAX:           1463 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00335895000msufc0206.fits
SUN_POSTN:       245.03d {+16h 20m 06s}  -21.45d {-21d 27' 13"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.58d {+17h 06m 18s}  -26.90d {-26d 53' 45"}
MOON_DIST:       132.43 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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 28 Nov 08 17:26:32 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.754d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.152d {+38d 09' 07"} (J2000)
ROLL:            280.784d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62531.34 SOD {17:22:11.34} UT,   206.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     249585734
X_OFFSET:        461 [pixels]
Y_OFFSET:        916 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       621
Y_GRB_POS:       1076
BINNING_INDEX:   1
IM_URL:          sw00335895000msuni0206.fits
SUN_POSTN:       245.03d {+16h 20m 06s}  -21.45d {-21d 27' 13"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.58d {+17h 06m 20s}  -26.90d {-26d 53' 46"}
MOON_DIST:       132.43 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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 28 Nov 08 17:26:52 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.754d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.152d {+38d 09' 07"} (J2000)
ROLL:            280.784d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62531.34 SOD {17:22:11.34} UT,   206.6 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     249585734
X_OFFSET:        461 [pixels]
Y_OFFSET:        916 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       621
Y_GRB_POS:       1076
BINNING_INDEX:   1
IM_URL:          sw00335895000msuni0206.fits
SUN_POSTN:       245.03d {+16h 20m 06s}  -21.45d {-21d 27' 13"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.59d {+17h 06m 21s}  -26.90d {-26d 53' 46"}
MOON_DIST:       132.43 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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 28 Nov 08 17:30:58 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     335895,   Seg_Num: 0
GRB_RA:           20.8050d {+01h 23m 13.19s} (J2000),
                  20.9330d {+01h 23m 43.92s} (current),
                  20.0885d {+01h 20m 21.24s} (1950)
GRB_DEC:         +38.1273d {+38d 07' 38.2"} (J2000),
                 +38.1736d {+38d 10' 25.1"} (current),
                 +37.8664d {+37d 51' 59.1"} (1950)
GRB_ERROR:       3.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  62641.00 SOD {17:24:01.00} UT,   316.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       245.03d {+16h 20m 07s}  -21.45d {-21d 27' 15"}
SUN_DIST:        138.72 [deg]   Sun_angle= -9.1 [hr] (East of Sun)
MOON_POSTN:      256.62d {+17h 06m 30s}  -26.90d {-26d 53' 51"}
MOON_DIST:       132.44 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.79,-24.32 [deg] galactic lon,lat of the burst
ECL_COORDS:       34.32, 27.09 [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 #8571
R. Margutti (Univ Bicocca&OAB), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), P. J. Brown (PSU), D. N. Burrows (PSU), S. Campana (INAF-OAB), M. Capalbi (ASDC), P.A. Curran (MSSL-UCL), P. A. Evans (U Leicester), C. Guidorzi (INAF-OAB), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), W.B Landsman (GSFC), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 17:18:44 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 081128 (trigger=335895). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 20.798, +38.115, which is
```
   RA(J2000)  =  01h 23m 12s
   Dec(J2000) = +38d 06' 54"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The TDRSS lightcurve for this image trigger does shows a possible peak (or possibly background variation during the slew).
The XRT began observing the field at 17:22:02.2 UT, 197.5 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 20.80537, 38.12728 which is equivalent to:
```
   RA(J2000)  = 01h 23m 13.29s
   Dec(J2000) = +38d 07' 38.2"
```
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This location is 48 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 6.09e+20 cm^-2 (Kalberla et al. 2005).
The initial flux in the 2.5 s image was 8.04e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 206 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05.
Burst Advocate for this burst is R. Margutti (raffaella.margutti 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:     Fri 28 Nov 08 17:35:57 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.756d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.153d {+38d 09' 09"} (J2000)
POINT_ROLL:      280.789d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  63178.62 SOD {17:32:58.62} UT,   853.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.552
N_STARS:         175
X_OFFSET:        0 [pixels]
Y_OFFSET:        356 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1795 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00335895000msufc0853.fits
SUN_POSTN:       245.03d {+16h 20m 08s}  -21.46d {-21d 27' 17"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.67d {+17h 06m 41s}  -26.90d {-26d 53' 57"}
MOON_DIST:       132.36 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 28 Nov 08 17:36:22 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.756d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.153d {+38d 09' 09"} (J2000)
POINT_ROLL:      280.789d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  63178.62 SOD {17:32:58.62} UT,   853.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.552
N_STARS:         175
X_OFFSET:        0 [pixels]
Y_OFFSET:        356 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1795 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00335895000msufc0853.fits
SUN_POSTN:       245.03d {+16h 20m 08s}  -21.46d {-21d 27' 17"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.67d {+17h 06m 42s}  -26.90d {-26d 53' 57"}
MOON_DIST:       132.36 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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 28 Nov 08 17:37:10 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.756d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.153d {+38d 09' 09"} (J2000)
ROLL:            280.789d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  63178.62 SOD {17:32:58.62} UT,   853.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     249586381
X_OFFSET:        559 [pixels]
Y_OFFSET:        915 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       719
Y_GRB_POS:       1075
BINNING_INDEX:   1
IM_URL:          sw00335895000msuni0853.fits
SUN_POSTN:       245.03d {+16h 20m 08s}  -21.46d {-21d 27' 18"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.68d {+17h 06m 44s}  -26.90d {-26d 53' 58"}
MOON_DIST:       132.36 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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:     Fri 28 Nov 08 17:37:22 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     335895,   Seg_Num: 0
POINT_RA:         20.756d {+01h 23m 01s} (J2000)
POINT_DEC:       +38.153d {+38d 09' 09"} (J2000)
ROLL:            280.789d
IMG_START_DATE:  14798 TJD;   333 DOY;   08/11/28
IMG_START_TIME:  63178.62 SOD {17:32:58.62} UT,   853.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     249586381
X_OFFSET:        559 [pixels]
Y_OFFSET:        915 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       719
Y_GRB_POS:       1075
BINNING_INDEX:   1
IM_URL:          sw00335895000msuni0853.fits
SUN_POSTN:       245.03d {+16h 20m 08s}  -21.46d {-21d 27' 18"}
SUN_DIST:        138.68 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      256.68d {+17h 06m 44s}  -26.90d {-26d 53' 58"}
MOON_DIST:       132.35 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      129.74,-24.30 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       34.29, 27.12 [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.

GCN Circular #8572
J.Wang, L.P. Xin, Y.L. Qiu, J.Y. Wei, J.Y. Hu, J.S. Deng, W.K. Zheng on behalf of EAFON report:
We began to observe GRB081128 (Margutti et al., GCN 8571) with Xinglong TNT telescope at 17:25:16(UT),6min32s after the burst.A series of white, R band have been obtained. After combined 10*20s white band data (without bias,flat-field correction) and made a preliminary analysis, a marginal object within the errorbar of XRT was detected with an estimated brightness of R ~ 20.9+/- 0.44 calibrated to USNO-B1.0, at the mean time of 500s after the burst.
We are not sure whether it is the OT or not, because of lack of flat images at the moment. We will reduce it tomorrow and give a more precise result and analysis.
This message may be cited.
For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org/grb/
GCN Circular #8573
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 2095 s of XRT Photon Counting mode data and 2 UVOT images for GRB 081128, 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 = 20.8041, +38.1271 which is equivalent to:
```
RA (J2000): 01h 23m 12.98s
Dec (J2000): +38d 07' 37.5"
```
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 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 #8574
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), R. Margutti (U Bicocca&OAB), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+303 sec from the recent telemetry downlink, we report further analysis of BAT GRB 081128 (trigger #335895) (Margutti, et al., GCN Circ. 8571). The BAT ground-calculated position is RA, Dec = 20.800, 38.123 deg, which is
```
   RA(J2000)  =  01h 23m 12.0s 
   Dec(J2000) = +38d 07' 23.8" 
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 74%.
The mask-weighted light curve shows two overlapping peaks. The first start probably before the object comes into the BAT FOV at T-95 sec and peaks at ~T=18 sec. The second peak peaks around T=35 sec and ends at ~T+90 sec. T90 (15-350 keV) is 100 +- 11 sec (estimated error including systematics).
The time-averaged spectrum from T-69.0 to T+62.7 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.08 +- 0.45, and Epeak of 45.1 +- 4.7 keV (chi squared 34.6 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+17.60 sec in the 15-150 keV band is 1.3 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.98 +- 0.09 (chi squared 48.9 for 57 d.o.f.). All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/335895/BA/
GCN Circular #8575
C.S Lin (NCU), Y. Urata (Saitama U/ASIAA) and K.Y Huang (ASIAA) on behalf of EAFON report:
"We observed the error region of GRB081128 (Margutti et al. GCN8571) using the Lulin 1m telescope from 10.9 min after the burst. The R-band images show possible optical afterglow as reported by Wang et al (GCN 8572) at RA=01:23:13.070 Dec=+38:07:38.77 with R=20.4 magnitude. However, the source shows no variability during our observations (10.9 -- 33.3 min after the burst).
```
 Time (min)  Rmag, error
 10.9        20.4  0.1
 33.3        20.4  0.1
```
There is no other optical sources in the XRT error region down to the R~21.4."
GCN Circular #8576
M. Andreev, A. Sergeev, (Terskol Branch of Institute of Astronomy), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the field of GRB 081128 detected by SWIFT (Margutti et al, GCN 8571) with the Z-600 telescope of Mt. Terskol observatory. A set of 90 s unfiltered exposures was taken starting (UT) Nov. 28 17:37. In a combined image of first exposures (3x90 s) we do not detect any new object in the enhanced XRT (Evans, et al, GCN 8573) up to 18.5m. In a combined image 18x90 s at mid time (UT) Nov. 28 18:08 we detect a faint object at coordinates (J2000) RA, Dec = 01 23 13.02 +38 07 38.1 with brightness of ~20.3m. A photometry and astrometry is preliminary and based on USNO-A2.0 and R mag of USNO-A2.0. Our photometry at ~ 50 min after burst is consistent with the photometry reported early (Wang et al, GCN 8572, Lin et al, GCN 8575) suggesting non fading source within XRT error box.
GCN Circular #8577
C. Guidorzi (INAF-OAB), N. Tanvir (U. Leicester), I.A. Steele, R.J. Smith, C.G. Mundell, D. Bersier (Liverpool JMU), A. Gomboc (U. Ljubljana) report on behalf of a larger collaboration:
On 2008 November 28 (22:16:14 UT) we began observing the field of GRB 081128 (Margutti et al. GCN Circ. 8571) with the Liverpool Telescope. Observations consisted of two sequences of 6x300s exposures acquired using the SDSS-i and SDSS-r filters, respectively.
In our coadded frame we detect a single source inside the refined XRT error box (Evans et al. GCN Circ. 8573) at the position RA(J2000)=01:23:13.05, Dec(J2000)=+38:07:38.7 (0.6" error radius) consistent with the optical candidate reported by Lin et al. (GCN Circ. 8575) and Andreev et al. (GCN Circ. 8576). We found the following magnitude for this object:
```
Telescope   Filter  T_mid[hr]   Exposure[s]    M_lim
-----------------------------------------------------------
LT          SDSS-r    6.66        6x300        21.9 +/- 0.2
-----------------------------------------------------------
```
The calibration was performed using the R2 magnitudes of several USNOB-1 catalogue field objects. Compared with the value reported by Lin et al. (GCN Circ. 8575), our measurement shows that the candidate has faded between the two epochs. There also appears to be a neighbouring source just outside the XRT error circle, which might be a host galaxy.
GCN Circular #8578
R. Margutti (Univ. Bicocca & INAF-OAB), J.Mao (INAF-OAB) and C. Guidorzi=20 (INAF-OAB) report on behalf of the Swift XRT team:
We have analysed the first 4 orbits of Swift-XRT data obtained for GRB 081128 (Margutti et al., GCN Circ.8571), covering 100 s of Windowed Timing (WT) and 6 ks of Photon Counting (PC) mode data, respectively, between 195 s and 35 ks after the trigger. The UVOT-enhanced XRT position was given by Evans et al. in GCN Circ.8573.
The light-curve can be modelled by a broken power-law, with a steep decay of alpha_1=3D4.1 =B1 0.2 and a break time of about 1000 s. =20 The decay then flattens to alpha_2=3D0.4 =B1 0.1
The spectrum extracted from WT data can be poorly modelled with an absorbed simple power-law, with Gamma =3D3.7 =B1 0.4 and NH =3D (2.7 =B1 0.1)x1021 cm-2 (P-value=3D5x10-5). The fit is statistically improved adding a black body component of temperature T=3D0.15 =B1 0.03 keV. In this case we obtain Gamma=3D 1.8 =B1= 0.6 and NH =3D (1.2 =B1 0.1)x1021 cm-2 (P-value=3D0.4). This result makes GRB 081128 similar to the sample considered by Moretti et al.,2008 A&A 478,409.
The spectrum extracted from PC data in the time interval 0.3-35 ks can be modelled with an absorbed power-law, with Gamma =3D 1.7 =B1 0.2 and a column density of NH =3D (0.5 =B1 0.4)x1021 cm-2,which is compatible with the Galactic value in this direction (0.6x1021 cm-2). The observed (unabsorbed) 0.3 -10 keV flux over this time interval is 3.0x10-12 (3.3x10-12) erg cm-2 s-1. Uncertainties are given at 90% confidence.
If the light-curve continues to decay with alpha ~0.4, the count rate 24 hours after the burst is estimated to be 9.2x10-3 count s-1, which corresponds to an observed flux of 4x10-13 erg cm-2 s-1.
The results of the xrt automatic analysis are available at http://www.swift.ac.uk/xrt_products/00335895.
This is an official product of the Swift-XRT team.
GCN Circular #8581
P. J. Brown (PSU) and R. Margutti (Univ. Biococca & OAB) report on behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 081128 starting 206 s after the BAT trigger (Margutti et al., GCN Circ. 8571). We do not detect any source inside the UVOT-enhanced XRT error circle (Evans, et al., GCN Circ. 8573) down to the following 3-sigma upper limits in the finding chart and co-added images:
```
Filter     T_start   T_stop    Exp(s)  Mag
------------------------------------------
  white       207      356      150   >20.9

  white       207      959      308   >21.3
     v        363     5643      247   >19.4
     b        462      826       58   >19.6
     u        437      801       58   >19.3
   uvw1       413      777       58   >19.0
   uvm2       388      752       58   >18.6
   uvw2       512     4429      236   >19.9

   white    10015    34512      625   >21.4
     v      27370    75499     3535   >21.0
-----------------------------------------
```
The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E(B-V) = 0.05 mag (Schlegel, et al., 1998, ApJS, 500, 525). All photometry is on the UVOT photometry system described in Poole et al. (2008, MNRAS, 383, 627).
GCN Circular #8584
On 2008 November 28 (19:55:36 UT) I began observing the field of GRB 0811= 28A (Margutti et al. GCN Circ. 8571) with the 0.5m reflector and ST-10XME CCD camera of Stara Lesna (Slovak Republic) observatory. Observations consisted of one sequence of 7x300s exposures acquired in standard Rc system. In my coadded frame it was not possible to detect a single source inside the refined XRT error box (Evans et al. GCN Circ. 8573) at the position RA(J2000)=3D01:23:13.05, Dec(J2000)=3D+38:07:38.7 with S/N rate more than= 5, which corresponds to Rc =3D 20.7. But on the level S/N =3D 3 one could me= asure the object with Rc =3D 21.6+/- 1.1. So I declare Rc =3D 20.7 as an upper = limit to the source which could be found within error box. The time of the middle of the sequence was 20:10:52 UT. The calibration was performed using the Rc magnitudes of SAO53150 (Scopal A&A 401, L17=E2=80=93L20, 2003) measured just after GRB 081128A observati= ons. The nearby to error box star GSC 2813 1599 =3D 12.66Rc +/-0.04 from this calibration. This study was supported by the SAI scholarship.
Igor Volkov, Astronomical Institute of the Slovak Academy of Sciences, 05= 9 60 Tatransk=C3=A1 Lomnica, Slovak Republic; e-mail: volkov@ta3.sk
[GCN OPS NOTE(30nov08): This circular was delayed ~17 hrs until the autho= r was added to the vetted list.]
GCN Circular #8594
S. Sergeev (CrAO), V. Rumyantsev (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the error box of Swift GRB 081128 (Margutti et al, GCN 8571) in I band on Nov. 28 between (UT) 20:20:28 - 20:31:16 with AZT-8 telescope of CrAO. Inside the refined XRT error box (Evans et al. GCN 8573) we do not detect the source reported as possible afterglow (Wang et al, GCN 8572; Lin et al, GCN 8575; Andreev et al, GCN 8576; Guidorzi et al, GCN 8577). The photometry of the combined image is following:
```
T0+    Filter, Exposure, mag.
(h)             (s)

3.23  I        5x120     >20.0 (3 sigma)
```
GCN Circular #8628
Brajesh Kumar, S. B. Pandey and Rupak Roy (ARIES, NainiTal, India, on behalf of larger Indian GRB collaboration)
GRB 081128, localized by Swift (Margutti et al. GCN 8571), was observed with 1.04m telescope at NainiTal starting ~ 2.5 hours after the burst in R_c filter.
Photometry of the co-added R_c frames (300 sec x 5) does not detect the optical afterglow candidate (Wang et al. GCN 8572) down to a limiting magnitude of ~ 20 mag in comparison to nearby USNO stars.
This message may be cited.
GCN Circular #8630
V. Rumyantsev, D. Shakhovkoy, S. Sergeev (CrAO), M.Andreev (Terskol Branch of Institute of Astronomy), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the error box of Swift GRB 081128 (Margutti et al, GCN 8571) in R band on Nov. 28 between (UT) 17:53:23 - 19:05:55 with AZT-11 telescope of CrAO. Inside the refined XRT error box (Evans et al. GCN 8573) we detect the source reported as possible afterglow (Wang et al, GCN 8572; Lin et al, GCN 8575; Andreev et al, GCN 8576; Guidorzi et al, GCN 8577). The coordinates of the source are RA(J2000): 01 23 13.03 Dec(J2000): +38 07 37.7 with uncertainty of 0.5". A photometry based on USNO-B1.0 star 1281-0027628 (01:23:11.75 +38:07:43.6) R2=17.91 is following:
```
T0+    Filter,  Exp.,   mag.        UL
(h)             (s)                (3 sigma)

1.207  R        23x180  21.5 +/-0.2  22.4
```
Taking above photometry and photometry reported earlier (Lin et al, GCN 8575; Andreev et al, GCN 8576; Guidorzi et al, GCN 8577) we confirm the fading nature of the source. We also detected the source (Guidorzi et al, GCN 8577) which is ~4" South of OT.
A combined image can be found at http://grb.rssi.ru/GRB081128/GRB081128_AZT11_R_18_31_09.gif
GCN Circular #8639
D. Malesani, J.P.U. Fynbo, G. Leloudas (DARK/NBI), H. Pedersen (NBI), P. Jakobsson (Univ. Iceland), S.-M. Niemi, H. Uthas, and C. Villforth (NOT), report on behalf of a larger collaboration:
We observed the field of GRB 081128 (Margutti et al., GCN 8571) with the Nordic Optical Telescope equipped with ALFOSC. Observations were carried out on two epochs, first on 2008 Nov 28.962 (0.24 days after the GRB) in the V, R and i bands and then on Dec 7.827 (9.10 days after the GRB) in the R band. In the first epoch we detect the afterglow candidate reported by Wang et al. (GCN 8572) in all filters. We estimate R=22.3 +- 0.1 assuming R=17.91 for the USNO star at RA = 01:23:11.73, Dec = +38:07:43.58 (consistent with the calibration of Guidorzi et al., GCN 8577; C. Guidorzi, priv. comm.). In the second epoch, the afterglow candidate remains undetected to a limit R > 23.5, and we hence confirm that this source is the GRB afterglow. We note that the V-band detection sets a limit on the GRB redshift, z <~ 5.
We also detect in both epochs a second object at the border of the XRT error circle (RA = 01:23:12.98, Dec = +38:07:38.4), which is likely the one reported by Guidorzi et al. (GCN 8577), with a magnitude R = 22.7. The angular separation from the afterglow is 1.2".
GCN Report 185.1
GCN_Report 185.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_185_1.pdf by R. Margutti at U. Bicocca and INAF-OAB titled: "Final Swift observations of GRB 081128"
arXiv:1504.02482 B-band detection of faint, blue host: z<4

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Jochen Greiner, last update: 07-Jul-2015 [Disclaimer]