Gamma-ray Burst 070220

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:44:47 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     261299,   Seg_Num: 0
GRB_RA:           34.819d {+02h 19m 17s} (J2000),
                  34.969d {+02h 19m 53s} (current),
                  33.776d {+02h 15m 06s} (1950)
GRB_DEC:         +68.818d {+68d 49' 06"} (J2000),
                 +68.851d {+68d 51' 03"} (current),
                 +68.588d {+68d 35' 17"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5630 [cnts]    Image_Peak=296 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       32746 [cnts]
BKG_TIME:        17054.22 SOD {04:44:14.22} UT
BKG_DUR:         8 [sec]
GRB_DATE:        14151 TJD;    51 DOY;   07/02/20
GRB_TIME:        17072.91 SOD {04:44:32.91} UT
GRB_PHI:         -167.89 [deg]
GRB_THETA:        38.45 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     20.83 [sigma]
IMAGE_SIGNIF:    10.51 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2 +14  +0  +1  +0  +1 
SUN_POSTN:       333.19d {+22h 12m 47s}  -11.06d {-11d 03' 43"}
SUN_DIST:         90.66 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.73d {+00h 18m 55s}   +3.85d {+03d 51' 18"}
MOON_DIST:        68.06 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.76,  7.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       62.10, 50.66 [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 = 122.61,20.15 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:46:19 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     261299,   Seg_Num: 0
GRB_RA:           34.7765d {+02h 19m 06.3s} (J2000),
                  34.9265d {+02h 19m 42.3s} (current),
                  33.7343d {+02h 14m 56.2s} (1950)
GRB_DEC:         +68.8052d {+68d 48' 18.7"} (J2000),
                 +68.8378d {+68d 50' 16.1"} (current),
                 +68.5751d {+68d 34' 30.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       134 [cnts]
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17151.70 SOD {04:45:51.70} UT,   78.8 [sec] since BAT Trigger Time
CENTROID_X:      298.17,  raw= 298  [pixels]
CENTROID_Y:      310.18,  raw= 310  [pixels]
ROLL:            239.65 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   28.72
GRB_POS_XRT_Z:   -9.73
IMAGE_URL:       sw00261299000msxps_rw.img
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 41"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.74d {+00h 18m 58s}   +3.86d {+03d 51' 45"}
MOON_DIST:        68.03 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       62.07, 50.66 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:46:19 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     261299,   Seg_Num: 0
GRB_RA:           34.7765d {+02h 19m 06.3s} (J2000),
                  34.9265d {+02h 19m 42.3s} (current),
                  33.7343d {+02h 14m 56.2s} (1950)
GRB_DEC:         +68.8052d {+68d 48' 18.7"} (J2000),
                 +68.8378d {+68d 50' 16.1"} (current),
                 +68.5751d {+68d 34' 30.2"} (1950)
GRB_ERROR:       4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       4.54e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.57 [sigma]
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17151.70 SOD {04:45:51.70} UT,   78.8 [sec] since BAT Trigger Time
TAM[0-3]:        327.63 237.18 261.31 242.99
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 41"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.74d {+00h 18m 58s}   +3.86d {+03d 51' 45"}
MOON_DIST:        68.03 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       62.07, 50.66 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact; see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:46:23 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     261299,   Seg_Num: 0
GRB_RA:           34.7765d {+02h 19m 06.3s} (J2000),
                  34.9265d {+02h 19m 42.3s} (current),
                  33.7343d {+02h 14m 56.2s} (1950)
GRB_DEC:         +68.8052d {+68d 48' 18.7"} (J2000),
                 +68.8378d {+68d 50' 16.1"} (current),
                 +68.5751d {+68d 34' 30.2"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       134 [cnts]
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17151.70 SOD {04:45:51.70} UT,   78.8 [sec] since BAT Trigger Time
CENTROID_X:      298.17,  raw= 298  [pixels]
CENTROID_Y:      310.18,  raw= 310  [pixels]
ROLL:            239.65 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   28.72
GRB_POS_XRT_Z:   -9.73
IMAGE_URL:       sw00261299000msxps_rw.img
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 41"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.74d {+00h 18m 58s}   +3.86d {+03d 51' 46"}
MOON_DIST:        68.03 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       62.07, 50.66 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:48:39 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.771d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.813d {+68d 48' 47"} (J2000)
POINT_ROLL:      239.653d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17161.40 SOD {04:46:01.40} UT,   88.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.205
N_STARS:         93
X_OFFSET:        352 [pixels]
Y_OFFSET:        568 [pixels]
X_MAX:           1311 [pixels]
Y_MAX:           1527 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00261299000msufc0088.fits
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 39"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.76d {+00h 19m 03s}   +3.87d {+03d 52' 26"}
MOON_DIST:        68.02 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:49:11 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.771d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.813d {+68d 48' 47"} (J2000)
POINT_ROLL:      239.653d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17161.40 SOD {04:46:01.40} UT,   88.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.205
N_STARS:         93
X_OFFSET:        352 [pixels]
Y_OFFSET:        568 [pixels]
X_MAX:           1311 [pixels]
Y_MAX:           1527 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00261299000msufc0088.fits
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 39"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.77d {+00h 19m 04s}   +3.88d {+03d 52' 35"}
MOON_DIST:        68.01 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 04:50:01 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.771d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.813d {+68d 48' 47"} (J2000)
ROLL:            239.653d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17161.40 SOD {04:46:01.40} UT,   88.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     193639563
X_OFFSET:        780 [pixels]
Y_OFFSET:        802 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       940
Y_GRB_POS:       962
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0088.fits
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 38"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.78d {+00h 19m 06s}   +3.88d {+03d 52' 50"}
MOON_DIST:        68.01 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 04:50:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.771d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.813d {+68d 48' 47"} (J2000)
ROLL:            239.653d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17161.40 SOD {04:46:01.40} UT,   88.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     193639563
X_OFFSET:        780 [pixels]
Y_OFFSET:        802 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       940
Y_GRB_POS:       962
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0088.fits
SUN_POSTN:       333.20d {+22h 12m 47s}  -11.06d {-11d 03' 38"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.78d {+00h 19m 07s}   +3.88d {+03d 52' 54"}
MOON_DIST:        68.01 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:55:48 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 54"} (J2000)
POINT_ROLL:      239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17266.70 SOD {04:47:46.70} UT,   193.8 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.620
N_STARS:         147
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00261299000msufc0193.fits
SUN_POSTN:       333.20d {+22h 12m 48s}  -11.06d {-11d 03' 33"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.83d {+00h 19m 19s}   +3.91d {+03d 54' 31"}
MOON_DIST:        67.97 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 04:56:11 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 54"} (J2000)
POINT_ROLL:      239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17266.70 SOD {04:47:46.70} UT,   193.8 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.620
N_STARS:         147
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00261299000msufc0193.fits
SUN_POSTN:       333.20d {+22h 12m 48s}  -11.06d {-11d 03' 32"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.83d {+00h 19m 20s}   +3.91d {+03d 54' 38"}
MOON_DIST:        67.97 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 04:57:11 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 54"} (J2000)
ROLL:            239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17266.70 SOD {04:47:46.70} UT,   193.8 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     193639668
X_OFFSET:        780 [pixels]
Y_OFFSET:        802 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       940
Y_GRB_POS:       962
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0193.fits
SUN_POSTN:       333.20d {+22h 12m 49s}  -11.06d {-11d 03' 31"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.84d {+00h 19m 22s}   +3.92d {+03d 54' 56"}
MOON_DIST:        67.96 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 04:57:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 54"} (J2000)
ROLL:            239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17266.70 SOD {04:47:46.70} UT,   193.8 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     193639668
X_OFFSET:        780 [pixels]
Y_OFFSET:        802 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       940
Y_GRB_POS:       962
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0193.fits
SUN_POSTN:       333.20d {+22h 12m 49s}  -11.06d {-11d 03' 31"}
SUN_DIST:         90.64 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.84d {+00h 19m 23s}   +3.92d {+03d 55' 02"}
MOON_DIST:        67.96 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #6114
M. Stamatikos (NASA/ORAU), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), S. Immler (GSFC/USRA), J. A. Kennea (PSU), F. E. Marshall (NASA/GSFC), C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (NASA/ORAU), P. Schady (MSSL-UCL) and D. E. Vanden Berk (PSU) report on behalf of the Swift Team:
At 04:44:33 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 070220 (trigger=261299). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 34.819, +68.818 which is
```
   RA(J2000)  = +02h 19m 17s
   Dec(J2000) = +68d 49' 06"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a duration of about 60 sec. The peak count rate was ~7000 counts/sec (15-350 keV), at ~15 sec after the trigger.
The XRT began observing the field at 04:45:51 UT, 79 seconds after the BAT trigger. XRT found a bright, fading, uncatalogued X-ray source located at RA, Dec 34.7765, +68.8052 which is
```
   RA(J2000)  =  02h 19m 06.3s
   Dec(J2000) =  68d 48' 18.7"
```
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This location is 72 arcseconds from the BAT on-board position, within the BAT error circle. The initial flux in the 2.5s image was 4.5e-09 erg/cm2/s (0.2-10 keV).
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 88 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 3-sigma upper limit in a 100s white band exposure is 19.6 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 0.90.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 05:06:08 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
POINT_ROLL:      239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17944.64 SOD {04:59:04.64} UT,   871.7 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.019
N_STARS:         165
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00261299000msufc0871.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 23"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.92d {+00h 19m 41s}   +3.96d {+03d 57' 33"}
MOON_DIST:        67.90 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 05:06:34 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
POINT_ROLL:      239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17944.64 SOD {04:59:04.64} UT,   871.7 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        2.019
N_STARS:         165
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00261299000msufc0871.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 23"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.93d {+00h 19m 42s}   +3.96d {+03d 57' 41"}
MOON_DIST:        67.90 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 05:07:33 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
ROLL:            239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17944.64 SOD {04:59:04.64} UT,   871.7 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     193640346
X_OFFSET:        779 [pixels]
Y_OFFSET:        801 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       939
Y_GRB_POS:       961
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0871.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 22"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.94d {+00h 19m 45s}   +3.97d {+03d 57' 58"}
MOON_DIST:        67.89 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 05:07:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
ROLL:            239.651d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  17944.64 SOD {04:59:04.64} UT,   871.7 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     193640346
X_OFFSET:        779 [pixels]
Y_OFFSET:        801 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       939
Y_GRB_POS:       961
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni0871.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 22"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.94d {+00h 19m 45s}   +3.97d {+03d 58' 03"}
MOON_DIST:        67.89 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 05:08:10 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
POINT_ROLL:      239.650d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  18352.72 SOD {05:05:52.72} UT,   1279.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.759
N_STARS:         131
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00261299000msufc1279.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 22"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.94d {+00h 19m 46s}   +3.97d {+03d 58' 09"}
MOON_DIST:        67.89 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Feb 07 05:08:37 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
POINT_ROLL:      239.650d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  18352.72 SOD {05:05:52.72} UT,   1279.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.759
N_STARS:         131
X_OFFSET:        460 [pixels]
Y_OFFSET:        482 [pixels]
X_MAX:           1419 [pixels]
Y_MAX:           1441 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00261299000msufc1279.fits
SUN_POSTN:       333.21d {+22h 12m 50s}  -11.06d {-11d 03' 21"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.95d {+00h 19m 47s}   +3.97d {+03d 58' 17"}
MOON_DIST:        67.89 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 05:09:28 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
ROLL:            239.650d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  18352.72 SOD {05:05:52.72} UT,   1279.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     193640754
X_OFFSET:        779 [pixels]
Y_OFFSET:        801 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       939
Y_GRB_POS:       961
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni1279.fits
SUN_POSTN:       333.21d {+22h 12m 51s}  -11.06d {-11d 03' 20"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.95d {+00h 19m 49s}   +3.98d {+03d 58' 31"}
MOON_DIST:        67.88 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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:     Tue 20 Feb 07 05:09:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     261299,   Seg_Num: 0
POINT_RA:         34.770d {+02h 19m 05s} (J2000)
POINT_DEC:       +68.815d {+68d 48' 55"} (J2000)
ROLL:            239.650d
IMG_START_DATE:  14151 TJD;    51 DOY;   07/02/20
IMG_START_TIME:  18352.72 SOD {05:05:52.72} UT,   1279.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     193640754
X_OFFSET:        779 [pixels]
Y_OFFSET:        801 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       939
Y_GRB_POS:       961
BINNING_INDEX:   1
IM_URL:          sw00261299000msuni1279.fits
SUN_POSTN:       333.21d {+22h 12m 51s}  -11.06d {-11d 03' 20"}
SUN_DIST:         90.63 [deg]   Sun_angle= -4.1 [hr] (East of Sun)
MOON_POSTN:        4.96d {+00h 19m 49s}   +3.98d {+03d 58' 36"}
MOON_DIST:        67.88 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      130.75,  7.28 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       62.07, 50.67 [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 #6115
A. Melandri (Liverpool JMU), A. Gomboc (Ljubljana), R. J. Smith, C. G. Mundell, C. Guidorzi, D. Carter, I. A. Steele, C. J. Mottram, D. F. Bersier, S. Kobayashi, M. F. Bode (Liverpool JMU), P. O'Brien, E. Rol, N. Bannister (Leicester) report
The 2-m Faulkes Telescope North robotically followed up GRB070220 (Stamatikos et al., GCN 6114, trigger=261299) beginning ~2 minutes after the GRB trigger time (UT:04:44:33).
No new object has been detected inside the XRT error circle (Stamatikos et al., GCN 6114) down to a limiting magnitude of R~19.5 for a coadded frame with a total exposure time of 420 sec, at a mean epoch of 28 min after the burst (comparison with respect to the USNO B1 catalog).
Further observations are ongoing.
GCN Circular #6117
A. Arai, M. Uemura and T. Uehara (Hiroshima Univ.), report on behalf of the KANATA GRB team:
We perfomed optical imaging of the field of GRB070220 (GCN 6114) at 9:59-10:20 UT 20 Feb. using TRISPEC attached to the KANATA 1.5-m telescope at Higashi-Hiroshima Observatory, Japan. We obtained 10 Rc-band images with a 123-s exposure time. The images were calibrated with neighbor stars in the USNO A2.0 catalog (r mag ).
We cannot significantly detect the optical afterglow at the position of the X-ray afterglow reported in GCN 6114 in our images. The limit magnitude is estimated to be 21.2 (3-sigma).
```
UT                      Limit mag in Rc    Exp. Time
Feb. 20.42381               21.2             123 * 10
```
GCN Circular #6118
A.P. Beardmore (U. Leicester), M. Stamatikos (NASA/ORAU), P.A. Evans, M.R. Goad, O. Godet, K.L. Page, (U. Leicester), M. Capalbi (ASDC), J.P. Osborne, R.L.C. Starling (U. Leicester) report on behalf of the Swift-XRT team:
We have analysed the first two orbits of Swift-XRT data available for GRB 070220 (Stamatikos et al., GCN 6114), which were obtained prior to the satellite entering the Malindi Gap. The data consist of 217s exposure in Windowed Timing (WT) mode and 4090s in Photon Counting (PC) mode.
Using the PC data, we find a refined XRT position, which has been astrometrically corrected by matching the UVOT images with the USNO-B1 catalogue, of:
```
RA(J2000)  =  02h 19m 06.83s
DEC(J2000) = +68d 48' 16.1"
```
with an uncertainty of 2.0 arcseconds (90% confidence). This position is 72.0 arcseconds and 3.0 arcseconds away from the original BAT and XRT positions quoted in GCN 6114.
The 0.3-10.0 keV X-ray light curve out to T+7.6ks (where T is the BAT trigger time) can be fit by a broken powerlaw, with an initial decay slope of 1.76+/-0.06, a break time of 417+/-43s, and a post-break slope of 0.99+/-0.04.
The WT spectrum from T+85s to T+294s can be modelled by an absorbed powerlaw, with a photon index of 1.55+/-0.08 and a column density of (4.9+/-0.5)e21 cm^-2 (compared with the Galactic value in this direction of 3.8e21 cm^-2). The 0.3-10.0 keV observed flux over this time interval is (1.21+/-0.05)e-9 ergs cm^-2 s^-1, which corresponds to an unabsorbed flux of (1.65+/-0.10)e-9 ergs cm^-2 s^-1.
While the temporal decay parameters are uncertain based on such limited data, assuming the source continues to fade at the same rate we predict an X-ray count rate of 0.019 count/s at T+24 hours, which corresponds to an observed (unabsorbed) 0.3-10.0 keV flux of 1.4e-12 (1.9e-12) ergs cm^2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular #6120
M. De Pasquale (MSSL/UCL) and M. Stamatikos (NASA/ORAU) report on behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 070220 starting 70 s after the BAT trigger (Stamatikos et al. 2007, GCN Circ. 6114) with the settling exposure. We do not find any source, in any of the UVOT observations, inside the refined XRT error circle (Beardmore et al., 2007 GCN Circ. 6118).
We have the following 3-sigma upper limits for a source inside the XRT error circle in the first exposure with White filter and in the co-added frames with all filters:
```
Filter         T_start   T_stop    Exp(s)    Mag (3-sigma UL)
-----------------------------------------------------------------
White           90         190        98     19.6

V              195        7101      1278     20.0
B              673        6487       276     20.2
U              649        7627       410     20.0
UVW1           625        7510       498     19.7
UVM2           601        7306       498     20.1
UVW2           701        6897       498     20.1
White           90        6691       638     20.6
-----------------------------------------------------------------
```
The values quoted above are not corrected for the expected Galactic extinction corresponding to a reddening of E_{B-V} = 0.9 mag towards the direction of the burst (Schlegel et al. 1998).
GCN Circular #6121
A. Parsons (GSFC), L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), 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-240 to T+1000 sec from the recent telemetry downlink, we report further analysis of BAT GRB 070220 (trigger #261299) (Stamatikos, et al., GCN Circ. 6114). The BAT ground-calculated position is RA, Dec = 34.800, 68.800 deg which is
```
   RA(J2000) = 2h 19m 11.9s 
   Dec(J2000) = 68d 48' 1.6" 
```
with an uncertainty of 1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 64%.
The mask-weighted lightcurve shows a multiple peaked structure. T90 (15-350 keV) is 129 +- 6 sec (estimated error including systematics).
The time-averaged spectrum from T-17 to T+240 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.45 +- 0.04. The fluence in the 15-150 keV band is 1.06 +- 0.02 x 10^-5 erg/cm2. The 1-sec peak photon flux measured from T+12 sec in the 15-150 keV band is 5.88 +- 0.29 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
GCN Circular #6122
K. Torii, S. Tanaka, and H. Tsunemi (Osaka U.) report:
The error region of GRB 070220 (Stamatikos et al. GCN 6114; Beardmore et al. GCN 6118) was observed with the 14 inch ART-3a and 0.35 m ART-3b, both located in Toyonaka, Osaka.
The imaging started at 2007 Feb. 20, 09:27:03 UT (4.7 hours after the burst) in Ic band (ART-3a), and at 09:55:44 UT in J band (ART-3b equipped with thermoelectrically cooled InGaAs array). We do not detect neither optical nor near infrared counterpart for the X-ray afterglow (GCN 6114, 6118), and derive the following 3 sigma upper limits relative to USNO-B1.0 I2 and 2MASS J magnitudes.
```
-----------------------------------------
StartUT		Filter	Limit	Exposure
=========================================
09:53:18	Ic	19.4	60s x 75
09:55:44        J	14.4	20s x 200
11:12:03	Ic	19.4	60s x 100
=========================================
```
GCN Circular #6123
M. Yoshida, K. Yanagisawa, (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We performed optical imaging observation of the field of GRB 070220 (GCN 6114, GCN 6118) with 50cm MITSuME telescope at Okayama Astrophysical Observatory from UT 9:57 to UT 12:11 on Feb. 20 2007.
We coadded 105 Ic band frames with a 1 minute exposure time. We made flux calibration using USNO B1.0 catalg. The three sigma limiting magnitude of our observation was 20.2 in Ic band. We could not find optical afterglow candidate in the error circle reported in GCN 6118.
```
----------------------------------------------------
band   mid-UT          exp.time       upper limit 
Ic     Feb. 20 11:24   105 x 1 min.   20.2 mag
----------------------------------------------------
```
GCN Circular #6124
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report:
The long GRB 070220 (Swift-BAT trigger #261299: Stamatikos et al., GCN 6114; Parsons et al., GCN 6121) triggered Konus-Wind at T0=17076.976 s UT (04:44:36.976). Konus-A observed GRB 070220 in the waiting mode.
The Konus-Wind light curve shows a multipeaked pulse with a long decaying tail clearly seen up to T-T0 ~130 sec in both G1(18-70 keV) and G2(70-300 keV) bands. So, the Swift XRT and UVOT were on target and begun observations during the hard prompt emission (Stamatikos et al., GCN 6114; Beardmore et al., GCN 6118; M. De Pasquale and M. Stamatikos 6120).
As observed by Konus-Wind the burst had a fluence of (2.98 +/- 1.15)x10^-5 erg/cm2, and the 256-ms peak flux measured from T0+9.600 s (2.47 +/- 0.50)x10^-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the GRB (from T0 to T0+123.136 s) is well fitted (in the 20 keV - 2 MeV range) by GRBM (Band) model for which: the low-energy photon index is alpha = -1.21 (-0.19, +0.29), the high energy photon index beta = -2.02 (-0.44, +0.27), the peak energy Ep = 299 (-130, +204) keV (chi2 = 52/60 dof). Fitting by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) * exp(-(2-alpha)*E/Ep) yields alpha = 1.33(-0.18, +0.15) and Ep = 443(-150, +420) keV (chi2 = 55/61 dof).
The spectrum of the burst maximum (accumulated from T0 s to T0+16.640 s) is well fitted (in the 20 keV - 2 MeV range) by GRBM (Band) model for which: the low-energy photon index is alpha = -1.04 (-0.15, 0.18), the high energy photon index beta = -2.07 (-0.36, 0.18), the peak energy Ep = 261 (-57, +81) keV (chi2 = 59/60 dof). The fluence of this part is 1.62(-0.20, +0.19)x10^-5 erg/cm2.
All the quoted errors are at the 90% confidence level.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB070220_T17076/
GCN Report 34.1
GCN_Report 34.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_34_1.pdf by M. Stamatikos at GSFC/ORAU titled: "Swift Observations on GRB 070220"
GCN Circular #6129
A. Pelangeon & J-L. Atteia (LATT-OMP) report:
We have used the spectral parameters of GRB 070220 provided by Golenetskii et al. (GCNC 6124) to compute the spectral pseudo-redshift** of this burst detected by SWIFT-BAT (Stamatikos et al., GCNC 6114; Parsons et al., GCNC 6121).
We find a pseudo-redshift pz=3D 2.15 =B1 0.80
** cf. http://www.ast.obs-mip.fr/grb/pz
GCN Circular #6135
C. Wigger, E. Bellm, M. Bandstra, S. Boggs, W. Hajdas, D. M. Smith, and K. Hurley on behalf of the RHESSI team report:
As observed by RHESSI, GRB070220 (M. Stamatikos et al., GCN 6114) had a duration of ~30s starting at about T0=04:44:33 UT. A fit to the time-integrated RHESSI spectrum of the main period of emission from T0 - T0+18s between 30 keV and 3.0 MeV gives a cutoff power law, with
```
alpha = -0.65 +0.40/-0.35
E0 = 235 +180/-90 keV
Epeak = 315 +115/-70 keV
(90% confidence levels).
```
The 20 keV-2 MeV fluence is (1.14 +0.16/-0.12) E-5 erg/cm^2.
GCN Circular #6149
Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf of=20 the Caltech-NRAO-Carnegie GRB Collaboration:
"We used the Very Large Array to observe the field of view toward GRB 070220 (GCN 6114) at a frequency of 8.46 GHz on 2007 February 24 at 0.94 UT. The GRB is undetected and the peak radio brightness at the=20 SWIFT-XRT position (GCN 6118) is 15 uJy =B1 50 uJy. =20
The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN Circular #6223
V. Rumyantsev (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed error box of GRB070220 (Stamatikos et al., GCN 6114) with Shajn 2.6m telescope of CrAO in R-band on Feb. 8 between (UT)19:25 and 19:53. No object is found in refined XRT error box (Beardmore et al., GCN 6118). Limiting magnitude of a combined image is based on USANO A2.0:
```
Mid time (UT),  Exposure,    R_Lim (3sigma)
Feb. 8.819      22x60        23.9
```
The combined image can be found in http://grb.rssi.ru/GRB070220/grb070220_R_ZTSh.gif
This message may be cited.

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