Gamma-ray Burst 080315

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 02:26:17 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     306323,   Seg_Num: 0
GRB_RA:          155.182d {+10h 20m 44s} (J2000),
                 155.304d {+10h 21m 13s} (current),
                 154.435d {+10h 17m 44s} (1950)
GRB_DEC:         +41.729d {+41d 43' 44"} (J2000),
                 +41.688d {+41d 41' 15"} (current),
                 +41.981d {+41d 58' 51"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1568 [image_cnts]
TRIGGER_DUR:     64.000 [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:        14540 TJD;    75 DOY;   08/03/15
GRB_TIME:        8701.35 SOD {02:25:01.35} UT
GRB_PHI:          15.29 [deg]
GRB_THETA:        15.93 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.51 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -2  +0  +0 +72  +1 
SUN_POSTN:       355.30d {+23h 41m 12s}   -2.03d {-02d 02' 03"}
SUN_DIST:        136.46 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.73d {+06h 14m 56s}  +27.69d {+27d 41' 16"}
MOON_DIST:        51.40 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.63, 56.02 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      140.81, 29.08 [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 = 296.43,11.28 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 02:27:19 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.176d {+10h 20m 42s} (J2000)
POINT_DEC:       +41.732d {+41d 43' 54"} (J2000)
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  8827.27 SOD {02:27:07.27} UT,   125.9 [sec] since BAT Trigger Time
COUNTS:          1    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        0    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:     Sat 15 Mar 08 02:29:01 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     306323,   Seg_Num: 0
GRB_RA:          155.182d {+10h 20m 44s} (J2000),
                 155.304d {+10h 21m 13s} (current),
                 154.435d {+10h 17m 44s} (1950)
GRB_DEC:         +41.729d {+41d 43' 44"} (J2000),
                 +41.688d {+41d 41' 15"} (current),
                 +41.981d {+41d 58' 51"} (1950)
GRB_DATE:        14540 TJD;    75 DOY;   08/03/15
GRB_TIME:        8701.35 SOD {02:25:01.35} UT
TRIGGER_INDEX:   20000
GRB_PHI:          15.29 [deg]
GRB_THETA:        15.93 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.51 [sigma]
LC_URL:          sw00306323000msb.lc
SUN_POSTN:       355.30d {+23h 41m 12s}   -2.03d {-02d 02' 00"}
SUN_DIST:        136.46 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.76d {+06h 15m 03s}  +27.69d {+27d 41' 08"}
MOON_DIST:        51.38 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.63, 56.02 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      140.81, 29.08 [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 = 296.43,11.28 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 02:36:15 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.176d {+10h 20m 42s} (J2000)
POINT_DEC:       +41.732d {+41d 43' 54"} (J2000)
POINT_ROLL:      330.148d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  8826.57 SOD {02:27:06.57} UT,   125.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.351
N_STARS:         22
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00306323000msufc0125.fits
SUN_POSTN:       355.31d {+23h 41m 13s}   -2.03d {-02d 01' 53"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.84d {+06h 15m 22s}  +27.68d {+27d 40' 48"}
MOON_DIST:        51.32 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 02:36:53 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.176d {+10h 20m 42s} (J2000)
POINT_DEC:       +41.732d {+41d 43' 54"} (J2000)
POINT_ROLL:      330.148d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  8826.57 SOD {02:27:06.57} UT,   125.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.351
N_STARS:         22
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00306323000msufc0125.fits
SUN_POSTN:       355.31d {+23h 41m 13s}   -2.03d {-02d 01' 53"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.85d {+06h 15m 23s}  +27.68d {+27d 40' 46"}
MOON_DIST:        51.32 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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:     Sat 15 Mar 08 02:37:34 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.176d {+10h 20m 42s} (J2000)
POINT_DEC:       +41.732d {+41d 43' 54"} (J2000)
ROLL:            330.148d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  8826.57 SOD {02:27:06.57} UT,   125.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     227240829
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni0125.fits
SUN_POSTN:       355.31d {+23h 41m 14s}   -2.03d {-02d 01' 52"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.85d {+06h 15m 25s}  +27.68d {+27d 40' 44"}
MOON_DIST:        51.31 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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:     Sat 15 Mar 08 02:38:01 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.176d {+10h 20m 42s} (J2000)
POINT_DEC:       +41.732d {+41d 43' 54"} (J2000)
ROLL:            330.148d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  8826.57 SOD {02:27:06.57} UT,   125.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     227240829
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni0125.fits
SUN_POSTN:       355.31d {+23h 41m 14s}   -2.03d {-02d 01' 52"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.86d {+06h 15m 26s}  +27.68d {+27d 40' 43"}
MOON_DIST:        51.31 [deg]
MOON_ILLUM:      57 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 02:46:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
POINT_ROLL:      330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9564.88 SOD {02:39:24.88} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.362
N_STARS:         22
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00306323000msufc0863.fits
SUN_POSTN:       355.31d {+23h 41m 15s}   -2.03d {-02d 01' 43"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.95d {+06h 15m 48s}  +27.67d {+27d 40' 19"}
MOON_DIST:        51.24 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN Circular #7416
K. L. Page (U Leicester), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), M. Stamatikos (NASA/ORAU), E. Troja (U Leicester/INAF-IASFPA) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 02:25:01 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080315 (trigger=306323). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 155.182, +41.729 which is
```
   RA(J2000) = 10h 20m 44s
   Dec(J2000) = +41d 43' 44"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual for a 64-second image trigger, the TDRSS light curve shows no obvious variation. Further BAT analysis will rely on the Malindi-downlinked data.
The XRT began observing the field at 02:27:07.3 UT, 125.9 seconds after the BAT trigger. No source was detected in the promptly available XRT data. We are waiting for the full dataset to detect and localise the XRT counterpart.
UVOT took a finding chart exposure of 400 seconds with the V filter starting 125 seconds after the BAT trigger. No afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of the BAT error circle. The typical 3-sigma upper limit has been about 18.5 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle. The list of sources is typically complete to about 18.0 mag. No correction has been made for the expected extinction of about 0.04 magnitudes.
Burst Advocate for this burst is K. L. Page (kpa AT star.le.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:     Sat 15 Mar 08 02:46:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
POINT_ROLL:      330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9564.88 SOD {02:39:24.88} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.362
N_STARS:         22
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00306323000msufc0863.fits
SUN_POSTN:       355.31d {+23h 41m 15s}   -2.03d {-02d 01' 43"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.96d {+06h 15m 49s}  +27.67d {+27d 40' 18"}
MOON_DIST:        51.24 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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:     Sat 15 Mar 08 02:47:31 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
ROLL:            330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9564.88 SOD {02:39:24.88} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     227241567
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni0863.fits
SUN_POSTN:       355.31d {+23h 41m 15s}   -2.03d {-02d 01' 42"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.96d {+06h 15m 51s}  +27.67d {+27d 40' 16"}
MOON_DIST:        51.23 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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:     Sat 15 Mar 08 02:47:58 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
ROLL:            330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9564.88 SOD {02:39:24.88} UT,   863.5 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     227241567
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni0863.fits
SUN_POSTN:       355.31d {+23h 41m 15s}   -2.03d {-02d 01' 42"}
SUN_DIST:        136.45 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       93.97d {+06h 15m 52s}  +27.67d {+27d 40' 14"}
MOON_DIST:        51.23 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 03:03:06 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
POINT_ROLL:      330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9970.03 SOD {02:46:10.03} UT,   1268.7 [sec] since BAT Trigger Time
FILTER:          4, UVM2
BKG_MEAN:        0.043
N_STARS:         10
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      3
PHOTO_THRESH:    2
SL_URL:          sw00306323000msufc1268.fits
SUN_POSTN:       355.32d {+23h 41m 17s}   -2.02d {-02d 01' 27"}
SUN_DIST:        136.44 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       94.13d {+06h 16m 32s}  +27.66d {+27d 39' 31"}
MOON_DIST:        51.11 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 03:03:36 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
POINT_ROLL:      330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9970.03 SOD {02:46:10.03} UT,   1268.7 [sec] since BAT Trigger Time
FILTER:          4, UVM2
BKG_MEAN:        0.043
N_STARS:         10
X_OFFSET:        459 [pixels]
Y_OFFSET:        602 [pixels]
X_MAX:           1418 [pixels]
Y_MAX:           1561 [pixels]
DET_THRESH:      3
PHOTO_THRESH:    2
SL_URL:          sw00306323000msufc1268.fits
SUN_POSTN:       355.32d {+23h 41m 17s}   -2.02d {-02d 01' 26"}
SUN_DIST:        136.44 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       94.14d {+06h 16m 33s}  +27.66d {+27d 39' 30"}
MOON_DIST:        51.11 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 15 Mar 08 03:04:11 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
ROLL:            330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9970.03 SOD {02:46:10.03} UT,   1268.7 [sec] since BAT Trigger Time
FILTER:          4, UVM2
EXPOSURE_ID:     227241972
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni1268.fits
SUN_POSTN:       355.32d {+23h 41m 18s}   -2.02d {-02d 01' 26"}
SUN_DIST:        136.44 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       94.14d {+06h 16m 35s}  +27.66d {+27d 39' 28"}
MOON_DIST:        51.11 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [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:     Sat 15 Mar 08 03:04:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     306323,   Seg_Num: 0
POINT_RA:        155.173d {+10h 20m 41s} (J2000)
POINT_DEC:       +41.731d {+41d 43' 52"} (J2000)
ROLL:            330.146d
IMG_START_DATE:  14540 TJD;    75 DOY;   08/03/15
IMG_START_TIME:  9970.03 SOD {02:46:10.03} UT,   1268.7 [sec] since BAT Trigger Time
FILTER:          4, UVM2
EXPOSURE_ID:     227241972
X_OFFSET:        778 [pixels]
Y_OFFSET:        921 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       938
Y_GRB_POS:       1081
BINNING_INDEX:   1
IM_URL:          sw00306323000msuni1268.fits
SUN_POSTN:       355.32d {+23h 41m 18s}   -2.02d {-02d 01' 25"}
SUN_DIST:        136.44 [deg]   Sun_angle= -10.7 [hr] (East of Sun)
MOON_POSTN:       94.15d {+06h 16m 35s}  +27.66d {+27d 39' 27"}
MOON_DIST:        51.10 [deg]
MOON_ILLUM:      58 [%]
GAL_COORDS:      177.62, 56.01 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      140.81, 29.08 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #7417
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 080315 detected by SWIFT (trigger 306323) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France.
The observations started 85.0s after the GRB trigger (9.4s after the notice). The elevation of the field decreased from from 45 degrees above horizon and weather conditions were excellents.
The date of trigger : t0 = 2008-03-15T02:25:01.3
The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT with a limiting magnitude of: t0+85.0s to t0+145.0s : R > 16.8
The second image is 30.0s exposure in tracking mode: t0+152.1s to t0+182.1s : R > 18.3
We co-added a series of exposures: t0+152.1s to t0+436.0s : R > 19.7
These images are unfiltered.
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon=177.6257 lat=+56.0163 and the galactic extinction in R band less than 0.1 magnitude estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.
GCN Circular #7418
A. de Ugarte Postigo (ESO, Chile), Virginie Chantry (U. Liege, Belgium), A.J. Castro-Tirado, M. Jelinek, J. Gorosabel (IAA-CSIC, Spain), C. Melo, A. Smette (ESO, Chile) report:
We have observed the field of GRB 080315 (Page et al., GCN 7416) with the 1.3m Mercator telescope at La Palma starting at 02:55 UT (30 min after the burst). The observation consisted on a series of 24x60s I-band exposures. The combined exposure, with mean time 3:26 UT (61.3 minutes after the burst), does not show any new source inside the 3 arcmin BAT error box down to a limiting magnitude of I~20.8 (USNO-B1.0 was used as photometric reference) as compared to SDSS i-band frame.
This message may be cited.
GCN Circular #7420
S. D. Barthelmy (GSFC), D. N. Burrows (PSU), J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), K. L. Page (U Leicester), D. Palmer (LANL)
After analysis of the data from the Swift BAT and XRT instruments, the Swift team is unable to conclude whether or not trigger is a real but faint burst or a statistical fluctuation. The source is detected at 7.1 sigma in the BAT 15-50 keV energy band. However, no bright source was found in the XRT data.
Using the data set from T-239 to T+303 sec from recent telemetry downlinks, we report further analysis of trigger 306323 (reported as GRB 080315, Page, et al., GCN Circ. 7416).
The BAT ground-calculated position is RA, Dec =3D 155.124 +41.701 deg which is
```
    RA(J2000)  =  10h 20m 29.8s
    Dec(J2000) = +41d 42' 3.6"
```
with an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment). The image significance at this location is 7.1 sigma. The partial coding was 98%.
The mask-weighted light curve shows a a single smooth bump starting at ~T-5 sec and and ending at ~T+65 sec. It appears only in the 15-50 keV band. T90 (15-350 keV) is 65 +- 5 sec (estimated error including systematics).
The time-averaged spectrum from T+0.0 to T+64.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.51 +- 0.59. The fluence in the 15-150 keV band is 1.4 +- 0.5 x 10-7 erg/cm2. The 1-sec peak photon flux measured from T+0.00 sec in the 15-150 keV band is 0.04 +- 0.01 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
In 20 ks of XRT Photon Counting mode data, a weak source is detected within the BAT error circle at a count rate of (9.5 =B1 3.0) X 10-4 count/s. The coordinates of this source are RA, Dec (J2000) = 155.0856, +41.6847, which is equivalent to
```
    RA  =  10 20 20.55
    Dec = +41 41 04.8
```
with an estimated uncertainty of 5 arcsec (90% containment). It is not possible to determine whether this source is fading because of the limited statistics. With the exception of this source, the 3-sigma upper limit within the BAT error circle is 5.9 X 10-4 count/s.
It is unusual, but not unprecedented for there to be no XRT detection of a Swift source. Among the BAT triggers of long GRBs with prompt slews, XRT sees a source approximately 97% of the time. Given the XRT non-detection and the faintness of the BAT source, we cannot tell whether this trigger is a statistical fluctuation or a real burst.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/306323/BA/
GCN Circular #7421
P. Schady (MSSL/UCL) and K. L. Page (U Leicester) report on behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 080315 starting 125 s after the BAT trigger (Page et al., GCN 7416). We do not find any source in any of the individual or co-added exposures, either within the BAT error circle or at the location of the weak source detected by XRT (Barthelmy et al. GCN 7420).
The 5-sigma upper limits for detecting a source at the position of the XRT candidate in the co-added images are:
```
Filter  T_start T_stop Exp      Mag
         (s)     (s)    (s)      (5-sigma upper limit)
-----------------------------------------------------
v       127     42160   6078.4  > 20.79
b       608     40422   5815.6  > 21.84
u       582     7467    620.7   > 20.30
uvw1    558     7281    468.7   > 19.82
uvm2    533     7075    858.7   > 20.00
uvw2    113     41328   5847.3  > 21.63
-----------------------------------------------------
```
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) = 0.01 mag. All photometry is on the UVOT light flight system described in Poole et al. (2008, MNRAS, 383, 627).
GCN Circular #7422
P.A.Milne (Steward Obs) and A. Updike report on behalf of the Super-LOTIS GRB team:
We observed the field of GRB 080315 starting at UT=02:43:58 (~19min since GRB) with the 2.3m Bok telescope at Kitt Peak, AZ. We obtained 23 x 60-sec and 7 x 120-sec images in the R-band filter.
We do not detect emission at the location of the faint XRT source (Palmer et al., GCN 7416) to a limiting magnitude of R~23.5.
We do not detect any sources other than ones apparent in the DSS, to the limit of the DSS image. We do not detect a fading/rising source between the initial 10 and final 10 images.
This message may be cited.
GCN Report 120.1
GCN_Report 120.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_120_1.pdf by K. Page at U. Leicester titled: "Final Swift observations of GRB 080315"
GCN Circular #7638
K.L. Page (U. Leicester) and N. Gehrels (NASA/GSFC) report on behalf of the Swift-XRT team:
Swift-XRT performed follow-up observations of the possible GRB 080315 (BAT trigger number 306323) about a month after the trigger, in order to determine whether or not the possible X-ray afterglow mentioned in GCN Circ. 7420 had faded. We find that this source is at a count rate consistent with that of our original observation, so conclude that it is not the afterglow. Thus, no afterglow was detected for this trigger.
Excluding this constant X-ray source, the 3-sigma upper limit within the BAT error circle from the observation directly following the trigger (25 ks on 2008-03-15) was 5.9 x 10^-4 count s^-1; the late-time data (30 ks between 2008-04-16 and 2008-04-21) provide a limit of 5.2 x 10^-4 count s^-1.
We cannot rule out that this was a real burst, but given the lack of XRT detection and marginal BAT detection it is not likely.

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Jochen Greiner, last update: 22-Apr-2008 [Disclaimer]