Gamma-ray Burst 070208

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:11:09 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     259714,   Seg_Num: 0 
GRB_RA:          197.920d {+13h 11m 41s} (J2000),
                 197.989d {+13h 11m 57s} (current),
                 197.440d {+13h 09m 45s} (1950)
GRB_DEC:         +61.959d {+61d 57' 31"} (J2000),
                 +61.921d {+61d 55' 16"} (current),
                 +62.224d {+62d 13' 26"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5800 [cnts]    Image_Peak=187 [image_cnts]
TRIGGER_DUR:     1.408 [sec]   
TRIGGER_INDEX:   472     E_range: 25-100 keV
BKG_INTEN:       56517 [cnts]
BKG_TIME:        33006.24 SOD {09:10:06.24} UT
BKG_DUR:         16 [sec]
GRB_DATE:        14139 TJD;    39 DOY;   07/02/08
GRB_TIME:        33034.28 SOD {09:10:34.28} UT
GRB_PHI:         -27.32 [deg]
GRB_THETA:        39.45 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.04 [sigma] 
IMAGE_SIGNIF:    7.29 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +2  +0  +0  +0 +48  +1
SUN_POSTN:       321.64d {+21h 26m 34s}  -15.06d {-15d 03' 30"}
SUN_DIST:        118.76 [deg]   Sun_angle= 8.2 [hr] (West of Sun) 
MOON_POSTN:      203.72d {+13h 34m 53s}  -13.62d {-13d 37' 18"} 
MOON_DIST:        75.68 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.78, 55.01 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      153.98, 60.15 [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 = 255.15,-1.98 [deg].

red DSS finding chart ps-file

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:12:37 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.904d {+13h 11m 37s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 30"} (J2000)
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33149.76 SOD {09:12:29.76} UT,   115.5 [sec] since BAT Trigger Time
COUNTS:          3    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:     Thu 08 Feb 07 09:14:14 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     259714,   Seg_Num: 0
GRB_RA:          197.920d {+13h 11m 41s} (J2000),
                 197.989d {+13h 11m 57s} (current),
                 197.440d {+13h 09m 45s} (1950)
GRB_DEC:         +61.959d {+61d 57' 31"} (J2000),
                 +61.921d {+61d 55' 16"} (current),
                 +62.224d {+62d 13' 26"} (1950)
GRB_DATE:        14139 TJD;    39 DOY;   07/02/08
GRB_TIME:        33034.28 SOD {09:10:34.28} UT
TRIGGER_INDEX:   472
GRB_PHI:         -27.32 [deg]
GRB_THETA:        39.45 [deg]
DELTA_TIME:      76.00 [sec]
TRIGGER_DUR:     1.408 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.04 [sigma]
IMAGE_SIGNIF:    7.29 [sigma]
LC_URL:          sw00259714000msb.lc
SUN_POSTN:       321.64d {+21h 26m 34s}  -15.06d {-15d 03' 27"}
SUN_DIST:        118.76 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.75d {+13h 34m 59s}  -13.63d {-13d 37' 57"}
MOON_DIST:        75.69 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.78, 55.01 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      153.98, 60.15 [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 = 255.15,-1.98 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:14:34 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.903d {+13h 11m 37s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 29"} (J2000)
POINT_ROLL:      66.345d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33153.19 SOD {09:12:33.19} UT,   118.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.097
N_STARS:         15
X_OFFSET:        523 [pixels]
Y_OFFSET:        310 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1269 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00259714000msufc0118.fits
SUN_POSTN:       321.64d {+21h 26m 35s}  -15.06d {-15d 03' 27"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.75d {+13h 34m 60s}  -13.63d {-13d 38' 02"}
MOON_DIST:        75.66 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:15:04 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.903d {+13h 11m 37s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 29"} (J2000)
POINT_ROLL:      66.345d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33153.19 SOD {09:12:33.19} UT,   118.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.097
N_STARS:         15
X_OFFSET:        523 [pixels]
Y_OFFSET:        310 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1269 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00259714000msufc0118.fits
SUN_POSTN:       321.64d {+21h 26m 35s}  -15.06d {-15d 03' 27"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.75d {+13h 35m 00s}  -13.64d {-13d 38' 08"}
MOON_DIST:        75.66 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:     Thu 08 Feb 07 09:15:52 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.903d {+13h 11m 37s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 29"} (J2000)
ROLL:            66.345d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33153.19 SOD {09:12:33.19} UT,   118.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     192618754
X_OFFSET:        842 [pixels]
Y_OFFSET:        629 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1002
Y_GRB_POS:       789
BINNING_INDEX:   1
IM_URL:          sw00259714000msuni0118.fits
SUN_POSTN:       321.64d {+21h 26m 35s}  -15.06d {-15d 03' 26"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.76d {+13h 35m 02s}  -13.64d {-13d 38' 18"}
MOON_DIST:        75.66 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:     Thu 08 Feb 07 09:16:11 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.903d {+13h 11m 37s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 29"} (J2000)
ROLL:            66.345d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33153.19 SOD {09:12:33.19} UT,   118.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     192618754
X_OFFSET:        842 [pixels]
Y_OFFSET:        629 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1002
Y_GRB_POS:       789
BINNING_INDEX:   1
IM_URL:          sw00259714000msuni0118.fits
SUN_POSTN:       321.64d {+21h 26m 35s}  -15.06d {-15d 03' 26"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.76d {+13h 35m 02s}  -13.64d {-13d 38' 22"}
MOON_DIST:        75.67 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:18:07 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.900d {+13h 11m 36s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 32"} (J2000)
POINT_ROLL:      66.340d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33258.45 SOD {09:14:18.45} UT,   224.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        0.514
N_STARS:         14
X_OFFSET:        523 [pixels]
Y_OFFSET:        310 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1269 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00259714000msufc0224.fits
SUN_POSTN:       321.65d {+21h 26m 35s}  -15.06d {-15d 03' 24"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.78d {+13h 35m 06s}  -13.65d {-13d 38' 46"}
MOON_DIST:        75.67 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:18:33 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.900d {+13h 11m 36s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 32"} (J2000)
POINT_ROLL:      66.340d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33258.45 SOD {09:14:18.45} UT,   224.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        0.514
N_STARS:         14
X_OFFSET:        523 [pixels]
Y_OFFSET:        310 [pixels]
X_MAX:           1482 [pixels]
Y_MAX:           1269 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00259714000msufc0224.fits
SUN_POSTN:       321.65d {+21h 26m 35s}  -15.06d {-15d 03' 24"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.78d {+13h 35m 07s}  -13.65d {-13d 38' 52"}
MOON_DIST:        75.67 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:     Thu 08 Feb 07 09:19:17 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.900d {+13h 11m 36s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 32"} (J2000)
ROLL:            66.340d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33258.45 SOD {09:14:18.45} UT,   224.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     192618860
X_OFFSET:        842 [pixels]
Y_OFFSET:        629 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1002
Y_GRB_POS:       789
BINNING_INDEX:   1
IM_URL:          sw00259714000msuni0224.fits
SUN_POSTN:       321.65d {+21h 26m 35s}  -15.06d {-15d 03' 23"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.78d {+13h 35m 08s}  -13.65d {-13d 39' 01"}
MOON_DIST:        75.68 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:     Thu 08 Feb 07 09:19:38 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     259714,   Seg_Num: 0
POINT_RA:        197.900d {+13h 11m 36s} (J2000)
POINT_DEC:       +61.925d {+61d 55' 32"} (J2000)
ROLL:            66.340d
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33258.45 SOD {09:14:18.45} UT,   224.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     192618860
X_OFFSET:        842 [pixels]
Y_OFFSET:        629 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1002
Y_GRB_POS:       789
BINNING_INDEX:   1
IM_URL:          sw00259714000msuni0224.fits
SUN_POSTN:       321.65d {+21h 26m 35s}  -15.06d {-15d 03' 23"}
SUN_DIST:        118.78 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      203.79d {+13h 35m 09s}  -13.65d {-13d 39' 05"}
MOON_DIST:        75.68 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.79, 55.04 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      154.02, 60.12 [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:        All 4 attachments are included.

GCN Circular #6074
G. Sato (GSFC/ISAS), S. D. Barthelmy (GSFC), S. Campana (INAF-OAB), M. L. Conciatore (ASDC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), C. Gronwall (PSU), C. Guidorzi (Univ Bicocca&INAF-OAB), V. Mangano (INAF-IASFPA), P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (Univ. Bicocca & INAF-OAB), G. Stratta (ASDC), G. Tagliaferri (INAF-OAB), S. D. Vergani (DIAS-DCU) and H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:
At 09:10:34 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 070208 (trigger=259714). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 197.920, +61.959 which is
```
   RA(J2000)  =  13h 11m 41s
   Dec(J2000) = +61d 57' 31"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak structure with a duration of about 2 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began taking data at 09:12:29 UT, 116 seconds after the BAT trigger. XRT could not centroid onboard, however in a 222 s ground-processed image, we found a previously uncatalogued X-ray source in the field of view at the following coordinates:
```
RA(J2000) = 13h 11m 32.77s
Dec(J2000)= +61d 57' 55.17"
```
with an uncertainty of 5 arcseconds radius (90% containment). This position lies 63 arcseconds from the center of the BAT error circle. The approximate initial flux is 1.044e-11 erg/cm2/sec (0.2-10 keV).
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 119 seconds after the BAT trigger. No afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 18.5 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.01.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 08 Feb 07 09:53:04 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     259714,   Seg_Num: 0
GRB_RA:          197.8865d {+13h 11m 32.7s} (J2000),
                 197.9547d {+13h 11m 49.1s} (current),
                 197.4054d {+13h 09m 37.2s} (1950)
GRB_DEC:         +61.9652d {+61d 57' 54.7"} (J2000),
                 +61.9276d {+61d 55' 39.2"} (current),
                 +62.2305d {+62d 13' 49.8"} (1950)
GRB_ERROR:       4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.04e-11 [erg/cm2/sec]
GRB_SIGNIF:      5.00 [sigma]
IMG_START_DATE:  14139 TJD;    39 DOY;   07/02/08
IMG_START_TIME:  33149.76 SOD {09:12:29.76} UT,   115.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.61 237.19 261.35 242.66
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       321.67d {+21h 26m 41s}  -15.05d {-15d 02' 57"}
SUN_DIST:        118.77 [deg]   Sun_angle= 8.2 [hr] (West of Sun)
MOON_POSTN:      204.04d {+13h 36m 10s}  -13.77d {-13d 46' 07"}
MOON_DIST:        75.85 [deg]
MOON_ILLUM:      69 [%]
GAL_COORDS:      118.81, 55.00 [deg] galactic lon,lat of the burst
ECL_COORDS:      153.95, 60.14 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values are not valid.

GCN Circular #6075
N. Mirabal and J. P. Halpern (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team:
"We have observed the Swift BAT localization of GRB 070208 (Sato et al., GCN 6074) with the MDM 1.3m telescope starting on February 8 09:25. Within the XRT error box, we detect two extended sources (also seen in the DSS plates), which should be considered potential host galaxies for this short burst. Observations are continuing to determine optical variability.
This message may be cited."
GCN Circular #6076
F. Yuan (U Mich), W. Rujopakarn (U Arizona), H. Swan (U Mich), E. S. Rykoff (U Mich) report on behalf of the ROTSE collaboration:
ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 070208 (Swift trigger 259714, GCN 6074, Sato, et al), producing images beginning 5.8 s after the GCN notice time. An automated response took the first image at 09:11:14.8 UT, 40.5 s after the burst, under fair conditions. We took 10 5-sec, 10 20-sec and 20 60-sec exposures. These unfiltered images are calibrated relative to USNO A2.0 (R).
Comparison to the DSS (second epoch) reveals no new sources within both the BAT and the XRT error circles, for both single images and coadding into sets of 10. We marginally detect one of the DSS objects detected by Mirabal & Halpern (GCN 6075) in our deepest images. Individual images have limiting magnitudes ranging from 15.9-17.0; we set the following specific limits.
```
start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
09:11:14.8   09:11:19.8         5     16.0           40.5       N
09:11:14.8   09:12:21.9        67     17.5           40.5       Y
09:12:29.9   09:17:25.5       295     18.2          115.6       Y
```
GCN Circular #6077
C. Guidorzi, C.G. Mundell, A. Monfardini,A. Gomboc, I. A. Steele, C.J. Mottram, R.J. Smith, M.F. Bode (Liverpool JMU), P. O'Brien, E. Rol, N. Bannister (Leicester) report:
"The 2-m Faulkes Telescope North robotically followed up GRB070208 (SWIFT trigger 259714; GCN 6074 Sato et al) 2.33 min after the GRB trigger time.
We identify a fading uncatalogued source at:
```
  13:11:32.51
  +61:57:54.5 (J2000)
```
This afterglow candidate is located close to but south-west of the extended galaxy visible in the SDSS. The of the two sources identified by Mirabal et al. (GCN 6075), we suggest the SW source is the afterglow.
Observations are ongoing."
GCN Circular #6078
D. B. Fox (PSU), E. Ofek (Caltech) and S. B. Cenko (Caltech) report on behalf of a larger collaboration:
"We have imaged the localization region for the afterglow of GRB 070208 (Sato et al., GCN 6074) with the robotic Palomar 60-inch telescope, in a series of exposures beginning at 09:15:33 UT, 5 minutes after the burst.
We confirm the point-like, fading nature of the afterglow candidate reported by Guidorzi et al. (GCN 6077), although given the nearby (candidate host) galaxy (Mirabel & Halpern, GCN 6075; Guidorzi et al., GCN 6077) we cannot exclude the presence of underlying diffuse emission at this time.
In our images the afterglow has i'~22 mag at 09:18 UT and i'~23.4 mag at 10:05 UT, corresponding to fading with power-law index alpha~-0.7 referenced to the burst epoch."
GCN Circular #6079
J. S. Bloom (UC Berkeley) reports on behalf of large group:
We began observing GRB 070208 (Sato et al. GCN 6074) with the robotic IR telescope PAIRITEL at 2007-02-08 09:12:26 UTC, 1 minute 52 seconds after the trigger. Consistent with the position of the fading source reported by Guidorzi et al. (GCN 6077; see also Fox et al. 6078) we find a new IR point source, offset from the nearby SDSS galaxy. Astrometry of the afterglow position relative to 2MASS gives a location of (J2000):
```
   RA: 13:11:32.607
   DEC: +61:57:54.37
```
(rms uncertainty of 350 mas in both coordinates). Adopting the nominal SDSS position for the center of the putative host (Mirabal et al. 6075), the afterglow is offset by 2.48" W, 2.77" S.
In a stacked exposure from 2007-02-08 09:12:26 to 09:28:44 we find a preliminary magnitude of J=17.52 +/- 0.16, Ks=16.19+/-0.18.
A finder showing the XRT position (Sato et al. 6074; yellow circle), SDSS sources (white squares), and the FTN optical afterglow position may be found at: http://lyra.berkeley.edu/~jbloom/grb070208.ps.gz
This message may be cited.
GCN Circular #6080
Richard J. Cool (Arizona), Daniel J. Eisenstein (Arizona), David W. Hogg (NYU), Michael R. Blanton (NYU), David J. Schlegel (LBNL), J. Brinkmann (APO), Donald Q. Lamb (Chicago), Donald P. Schneider (PSU), and Daniel E. Vanden Berk (PSU) report:
The Sloan Digital Sky Survey (SDSS) imaged the field of burst GRB070208 prior to the burst. As these data should be useful as a pre-burst comparison and for calibrating photometry, we are supplying the images and photometry measurements for this GRB field to the community.
Data from the SDSS, including 5 FITS images, 3 JPGS, and 3 files of photometry and astrometry, are being placed at http://mizar.as.arizona.edu/~grb/public/GRB070208
We supply FITS images in each of the 5 SDSS bands of a 8'x8' region centered on the GRB position (ra=197.887 (13:11:32.8), dec=61.9653 (61:57:55.2); GCN 6074), as well as 3 gri color-composite JPGs (with different stretches). The units in the FITS images are nanomaggies per pixel. A pixel is 0.396 arcsec on a side. A nanomaggie is a flux-density unit equal to 10^-9 of a magnitude 0 source or, to the extent that SDSS is an AB system, 3.631e-6 Jy. The FITS images have WCS astrometric information.
In the file GRB070208_sdss.calstar.dat, we report photometry and astrometry of 140 bright stars (r<20.5) within 15' of the burst location. The magnitudes presented in this file are asinh magnitudes as are standard in the SDSS (Lupton 1999, AJ, 118, 1406). Beware that some of these stars are not well- detected in the u-band; use the errors and object flags to monitor data quality.
In the files GRB070208_sdss.objects_flux.dat and GRB070208_sdss.objects_magnitudes.dat, we report photometry of 329 objects detected within 6' of the GRB position. We have removed saturated objects and objects with model magnitudes fainter than 23.0 in the r- band. The fluxes listed in GRB070208_sdss.objects_flux.dat are in nanomaggies while the magnitudes listed in GRB070208_sdss.objects_magnitudes.dat are asinh magnitudes.
All quantities reported are standard SDSS photometry, meaning that they are very close to AB zeropoints and magnitudes are quoted in asinh magnitudes. Photometric zeropoints are known to about 2% rms. None of the photometry is corrected for dust extinction. The Schlegel, Finkbeiner, and Davis (1998) predictions for this region are A_U=0.084 mag, A_g=0.062 mag, A_r = 0.045 mag, A_i=0.034 mag, and A_z=0.024 mag.
The file GRB070208_sdss.spectro.dat contains a list of the 3 objects with SDSS spectroscopy within 6 arcminutes of the GRB position. In addition to the redshift and 1-sigma error for each object, this file also lists the object spectroscopic classification.
SDSS astrometry is generally better than 0.1 arcsecond per coordinate. Users requiring high precision astrometry should take note that the SDSS astrometric system can differ from other systems such as those used in other notices; we have not checked the offsets in this region.
More detailed information pertaining to our SDSS GRB releases can be found in our initial data release paper (Cool et al. 2006, PASP, 118, 733). See the SDSS DR4 documentation for more details: http://www.sdss.org/dr5.
These data have been reduced using a slightly different pipeline than that used for SDSS public data releases. We cannot guarantee that the values here will exactly match those in the data release in which these data are included. In particular, we expect the photometric calibrations to differ by of order 0.01 mag.
This note may be cited, but please also cite the SDSS data release paper, Adelman-McCarthy et al. (2006, ApJS, 162, 38), when using the data or referring to the technical documentation.
GCN Circular #6081
C. Markwardt (GSFC/UMD), L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC) on behalf of the Swift-BAT team:
Using the data set from T-239 to T+552 sec from the recent telemetry downlink, we report further analysis of BAT GRB 070208 (trigger #259714) (Sato, et al., GCN Circ. 6074). The BAT ground-calculated position is RA, Dec = 197.896, 61.946 deg which is
```
   RA(J2000)  = 13h 11m 35.0s 
   Dec(J2000) = 61d 56' 44.3" 
```
with an uncertainty of 3.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 50%.
The mask-weighted lightcurve shows two peaks. The first (at T_zero) is FRED-like with a duration of ~7 sec. The second starts at ~T+35 sec and ends at ~T+50 sec. T90 (15-350 keV) is 48 +- 2 sec (estimated error including systematics).
The time-averaged spectrum from T-1.0 to T+47.8 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.96 +- 0.37. The fluence in the 15-150 keV band is 4.3 +- 1.0 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T-0.26 sec in the 15-150 keV band is 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
Fitting the two peaks separately with a simple power law model, -2 to 5 s: photon index = 2.17 -0.44 +0.53 25 to 50 s: photon index = 1.69 -0.34 +0.36 Given the widths of the two peaks and that the second peak is spectrally harder than the first, we conclude that this burst is a long GRB and is not a short hard burst with extended emission.
GCN Circular #6082
J. P. Halpern & N. Mirabal (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team:
"Monitoring of the afterglow of GRB 070208 (GCNs 6077, 6078, 6079) in the R-band on the MDM 1.3m telescope consisted of a series of 10-minute exposures beginning on Feb. 8 09:25 UT and ending at 13:12 UT, thus spanning the time 0.25-4 hours after the burst. Partly cloudy conditions, together with bright moonlight, resulted in images of highly variable quality. Nevertheless, we see the fading optical transient within the Swift XRT error circle (Sato et al., GCN 6074). In agreement with the GCNs listed above, we find the OT 3.0" west and 3.3" south of the center of a galaxy visible on the POSS (Mirabal & Halpern, GCN 6075) and in pre-burst SDSS images (Cool et al., GCN 6080).
Preliminary magnitudes for the OT, calibrated with respect to USNO B1.0 magnitudes of nearby stars, are R=20.04+/-0.08 for the first exposure centered at 09:30 UT, and R=21.5+/-0.2 for a summed 30-minute exposure centered at 12:55 UT. Some contamination from the nearby galaxy is possible in this analysis. Quoted uncertainties are statistical only. This corresponds to a mean power-law decay index of -0.55.
It is not yet clear from this collection of images, both SDSS and MDM, if the visible galaxy is the host, or if we should wait to see if a fainter galaxy underlies the OT of this judged long burst (Markwardt et al., GCN 6081).
Images are posted at http://www.astro.columbia.edu/~jules/grb/070208/
This message may be cited."
GCN Circular #6083
A. Cucchiara (PSU), D. B. Fox (PSU), S. B. Cenko (Caltech) and P. A. Price (Hawaii) report on behalf of a larger collaboration:
"We observed the optical afterglow (Guidorzi et al., GCN 6077, Fox et al., GCN 6078) of GRB 070208 (Sato et al., GCN 6074) with the Gemini-North telescope + Gemini Multi-Object Spectrograph in four 1800-s integrations with mean epoch 11:37 UT on 8 Feb 2007 (approximately 2.5 hours after the burst). Our spectral coverage is 4000-8300 A. The bright nearby galaxy seen in archival images (e.g., Mirabal & Halpern, GCN 6075) does not fall within our slit.
At the afterglow position we observe a strong [OII] (3727 A) emission line at redshift z=1.165 superposed on the afterglow continuum, along with multiple metal absorption features consistent with this redshift, including: the MgII (2796.4 A, 2803.5 A) doublet, FeII (2600.5 A), and MnII (2576.9 A).
We conclude that the redshift of GRB 070208 and its underlying host galaxy is z=1.165."
GCN Circular #6084
J. Wren, W.T. Vestrand, P.R. Wozniak, R. White, J. Pergande of Los Alamos National Laboratory report:
Our Raptor-S telescope responded to Swift trigger 259714 (Sato et al., GCN 6074) at 09:11:17.10 UT, 42.8 s after the trigger and 6.3 s after receiving the GCN packet. We clearly detect the source at the location of the optical counterpart identified by Guidorzi et al. (GCN 6077). Our first 5 second exposure was obtained while the Swift BAT was still detecting emission from the second GRB pulse (Markwardt et al., GCN 6081). Our measurements show that the optical counterpart brightened from fainter than magnitude 18.7 to 18.2 in the first 300 seconds after the trigger time and then began to fade steadily after that. Our unfiltered magnitudes were calibrated using the R-band magnitudes from the USNO B1.0 catalog.
GCN Circular #6085
M.L. Conciatore, G. Stratta, M. Perri (ASDC), G. Sato (GSFC/ISAS) D. Burrows (PSU) report on behalf of the Swift/XRT team:
We have analysed the first seven orbits of XRT data GRB070208. A 11.7 ks photon counting mode image provides a refined XRT position:
```
RA(J2000) =13h 11m 32.73s,
Dec(J2000) =+61d 57m 55.20s
```
with an uncertainty of 3.7 arcsec (90% containment). This position is 0.3 arcsec from the XRT position quoted in Sato et el. (GCN Circ. 6074), 72 arcsec from the ground-calculated BAT position reported by Markwardt et al. (GCN Circ. 6081) and 1.7 arcsec from the fading source reported by Guidorzi et al. (GCN Circ. 6077; see also Fox et al., GCN Circ. 6078).
The 0.3-10 keV X-ray light-curve, after an initial slow rising phase, shows a steep decay (alpha~-3.6) during the second orbit (from T+4.3ks to T+6.7ks). Starting from the third orbit, the light-curve shows a power-law decline with a decay index of 1.8+/-0.4.
The X-ray spectrum is well fitted by an absorbed power-law with a photon index of 2.6 +/- 0.2 and column density of (2.6 +/-0.4 )e21 cm**-2. We note the Galactic column density in the direction of the source is 1.7e20 cm**-2. The 0.3-10 keV observed flux was 1.5e-12 ergs cm**-2 s**-1, which corresponds to an unabsorbed flux of 3.5e-12 ergs cm**-2 s**-1.
If the burst continues decaying at the current rate we estimate an XRT count rate of 0.002 counts/s at T + 24hr, which corresponds to an observed 0.3-10 keV flux of 2.3e-13 ergs cm**-2 s**-1
This circular is an official product of the Swift XRT Team.
GCN Circular #6090
H. Swan (U. Michigan), I. Smith (Rice), M. Skinner (AMOS Observatory, Boeing LTS), R. Russell, (Aerospace Corporation), report on behalf of the MARGE collaboration:
The AEOS Burst Camera (ABC) on the AEOS telescope located at the Maui Space Surveillance System on Haleakala Maui began imaging Swift GRB070208 (GCN 6074 Sato et al) on Feb 8, 2007 at 09:22:38.11 UTC, ~12 minutes after the GRB was detected. These are unfiltered optical images. After coadding our 10s images in sets of 10, we find the OT first identified by Guidorzi et al. (GCN 6077). Using the SDSS data provided by Cool et al (GCN 6080), we calibrate the OT to the r band magnitude of the star located at RA=197.89688 Dec=61.97785. The approximate statistical errors are 0.2 magnitudes. We report the following magnitudes for the OT:
```
time            ABC mag
09:22:38.11 UT  mag= 20.3
09:35:10.03 UT  mag= 20.3
09:59:46.08 UT  mag= 20.9
10:02:53.99 UT  mag= 20.8
```
The Rice University CCD Camera (RUCCD) on the AEOS telescope also observed GRB 070208. Ic-band images were taken between 2007-02-08 09:49 UT and 10:35 UT. The results are consistent with the Palomar observations of Fox et al. (GCN 6078).
GCN Report 31.1
GCN_Report 31.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_31_1.pdf by G. Sato at GSFC titled: "Swift Observations of GRB 070208"
GCN Circular #6093
E. Klunko (ISTP), V. Kouprianov (GAO), A. Pozanenko (IKI), V.Rumyantsev (CrAO) on behalf of larger GRB follow up collaboration report:
We observed the error box of GRB070208 (Barthelmy et al., GCN 6074) with 1.5m telescope of Sayan Observatory (Mondy) in R-bands on Feb.08 between (UT) 15:43 and 19:28. Series of 300 s exposures were taken under not optimal weather conditions. We detect fading source (Guidorzi et al., GCN 6077, Fox et al., GCN 6078, Bloom et al., GCN 6079) contaminated by nearby galaxy (Mirabal & Halpern, GCN 6075). Detailed photometry will be done after additional observation of the galaxy.
This message may be cited.
GCN Circular #6222
E. Klunko (ISTP), A. Shulga, A. Volnova (SAI MSU), V. Kouprianov (GAO), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the afterglow of GRB070208 (Guidorzi et al., GCN 6077, Fox et al., GCN 6078, Bloom GCN 6079) in R-band on Feb.8 with 1.5m telescope of Sayan observatory. A set of 300 s exposures was obtained between (UT) 15:43 and 19:28 (Klunko et al., GCN 6093). Best combined image of total exposure 4200 s is centered at Feb. 7.785. After mask subtraction of the nearby galaxy in the best combined image we estimate OT magnitude as following:
```
Mid time (UT), Exposure,  R_mag
Feb. 7.785     14x300 s   21.4 +/- 0.2
```
The photometry is based on USNO A2.0 stars. The mask subtracted image can be found in http://grb.rssi.ru/GRB070208/
The message may be cited.

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Jochen Greiner, last update: 23-Mar-2007 [Disclaimer]