Gamma-ray Burst 050807

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Sun 07 Aug 05 10:58:52 UT
NOTICE_TYPE:    HETE S/C_Alert
TRIGGER_NUM:    3889,   Seq_Num: 1
GRB_DATE:       13589 TJD;   219 DOY;   05/08/07
GRB_TIME:       39524.94 SOD {10:58:44.94} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     151  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       326 [deg]
SC_-Z_DEC:      -14 [deg]
SC_LONG:        160 [deg East]
SUN_POSTN:      137.51d {+09h 10m 01s}  +16.32d {+16d 19' 24"}
MOON_POSTN:     163.19d {+10h 52m 45s}  +10.28d {+10d 16' 34"}
MOON_ILLUM:     5 [%]
COMMENTS:       Probable GRB.

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Sun 07 Aug 05 10:59:12 UT
NOTICE_TYPE:    HETE S/C_Update
TRIGGER_NUM:    3889,   Seq_Num: 2
GRB_DATE:       13589 TJD;   219 DOY;   05/08/07
GRB_TIME:       39524.94 SOD {10:58:44.94} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     151  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       326 [deg]
SC_-Z_DEC:      -14 [deg]
SC_LONG:        160 [deg East]
WXM_CNTR_RA:    304.650d {+20h 18m 36s} (J2000),
                304.738d {+20h 18m 57s} (current),
                303.862d {+20h 15m 27s} (1950)
WXM_CNTR_DEC:   -32.568d {-32d 34' 02"} (J2000),
                -32.550d {-32d 32' 58"} (current),
                -32.724d {-32d 43' 26"} (1950)
WXM_MAX_SIZE:   60.00 [arcmin] diameter
WXM_LOC_SN:     11 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 11.0 Y= 3.0 [sig/noise]
WXM_LC_SN:      X= 10.5 Y= 2.5 [sig/noise]
SUN_POSTN:      137.51d {+09h 10m 01s}  +16.32d {+16d 19' 24"}
SUN_DIST:       160.08 [deg]
MOON_POSTN:     163.19d {+10h 52m 45s}  +10.28d {+10d 16' 34"}
MOON_DIST:      138.21 [deg]
MOON_ILLUM:     5 [%]
GAL_COORDS:     9.67,-31.59 [deg] galactic lon,lat of the burst
ECL_COORDS:     299.41,-12.60 [deg] ecliptic lon,lat of the burst
COMMENTS:       Probable GRB.
COMMENTS:       WXM error box is circular; not rectangular.

red DSS finding chart ps-file

GCN/SWIFT NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Sun 07 Aug 05 10:59:19 UT
NOTICE_TYPE:    HETE S/C_Update
TRIGGER_NUM:    3889,   Seq_Num: 3
GRB_DATE:       13589 TJD;   219 DOY;   05/08/07
GRB_TIME:       39524.94 SOD {10:58:44.94} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     151  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       326 [deg]
SC_-Z_DEC:      -14 [deg]
SC_LONG:        160 [deg East]
WXM_CNTR_RA:    303.200d {+20h 12m 48s} (J2000),
                303.291d {+20h 13m 10s} (current),
                302.380d {+20h 09m 31s} (1950)
WXM_CNTR_DEC:   -37.373d {-37d 22' 22"} (J2000),
                -37.356d {-37d 21' 20"} (current),
                -37.524d {-37d 31' 25"} (1950)
WXM_MAX_SIZE:   60.00 [arcmin] diameter
WXM_LOC_SN:     13 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 13.2 Y= 3.2 [sig/noise]
WXM_LC_SN:      X= 11.2 Y= 2.5 [sig/noise]
SUN_POSTN:      137.51d {+09h 10m 01s}  +16.32d {+16d 19' 24"}
SUN_DIST:       155.51 [deg]
MOON_POSTN:     163.19d {+10h 52m 45s}  +10.28d {+10d 16' 34"}
MOON_DIST:      135.10 [deg]
MOON_ILLUM:     5 [%]
GAL_COORDS:     3.86,-31.51 [deg] galactic lon,lat of the burst
ECL_COORDS:     297.07,-17.00 [deg] ecliptic lon,lat of the burst
COMMENTS:       Probable GRB.
COMMENTS:       WXM error box is circular; not rectangular.

GCN/SWIFT NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Sun 07 Aug 05 11:02:10 UT
NOTICE_TYPE:    HETE S/C_Last
TRIGGER_NUM:    3889,   Seq_Num: 4
GRB_DATE:       13589 TJD;   219 DOY;   05/08/07
GRB_TIME:       39524.94 SOD {10:58:44.94} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     151  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       326 [deg]
SC_-Z_DEC:      -14 [deg]
SC_LONG:        160 [deg East]
WXM_CNTR_RA:    303.200d {+20h 12m 48s} (J2000),
                303.291d {+20h 13m 10s} (current),
                302.380d {+20h 09m 31s} (1950)
WXM_CNTR_DEC:   -37.373d {-37d 22' 22"} (J2000),
                -37.356d {-37d 21' 20"} (current),
                -37.524d {-37d 31' 25"} (1950)
WXM_MAX_SIZE:   60.00 [arcmin] diameter
WXM_LOC_SN:     13 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 13.2 Y= 3.2 [sig/noise]
WXM_LC_SN:      X= 11.2 Y= 2.5 [sig/noise]
SUN_POSTN:      137.51d {+09h 10m 01s}  +16.32d {+16d 19' 24"}
SUN_DIST:       155.51 [deg]
MOON_POSTN:     163.19d {+10h 52m 45s}  +10.28d {+10d 16' 34"}
MOON_DIST:      135.10 [deg]
MOON_ILLUM:     5 [%]
GAL_COORDS:     3.86,-31.51 [deg] galactic lon,lat of the burst
ECL_COORDS:     297.07,-17.00 [deg] ecliptic lon,lat of the burst
COMMENTS:       Probable GRB.
COMMENTS:       WXM error box is circular; not rectangular.

GCN/SWIFT NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Sun 07 Aug 05 13:47:18 UT
NOTICE_TYPE:    HETE Ground Analysis
TRIGGER_NUM:    3889,   Seq_Num: 5
GRB_DATE:       13589 TJD;   219 DOY;   05/08/07
GRB_TIME:       39524.93 SOD {10:58:44.93} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     151  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       325 [deg]
SC_-Z_DEC:      -14 [deg]
SC_LONG:        160 [deg East]
WXM_CNTR_RA:    303.361d {+20h 13m 27s} (J2000),
                303.453d {+20h 13m 49s} (current),
                302.545d {+20h 10m 11s} (1950)
WXM_CNTR_DEC:   -36.952d {-36d 57' 06"} (J2000),
                -36.935d {-36d 56' 04"} (current),
                -37.103d {-37d 06' 11"} (1950)
WXM_CORNER1:    303.3159 -37.3620 [deg]
WXM_CORNER2:    303.1650 -37.3150 [deg]
WXM_CORNER3:    303.4070 -36.5420 [deg]
WXM_CORNER4:    303.5580 -36.5890 [deg]
WXM_MAX_SIZE:   49.38 [arcmin] diameter
WXM_LOC_SN:     2 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 14.5 Y= 8.6 [sig/noise]
WXM_LC_SN:      X= 25.5 Y= 8.4 [sig/noise]
SXC_CNTR_RA:    303.361d {+20h 13m 27s} (J2000),
                303.452d {+20h 13m 48s} (current),
                302.544d {+20h 10m 11s} (1950)
SXC_CNTR_DEC:   -36.937d {-36d 56' 12"} (J2000),
                -36.920d {-36d 55' 10"} (current),
                -37.088d {-37d 05' 17"} (1950)
SXC_CORNER1:    303.4120 -36.6730 [deg]
SXC_CORNER2:    303.2490 -37.1890 [deg]
SXC_CORNER3:    303.3080 -37.2050 [deg]
SXC_CORNER4:    303.4740 -36.6810 [deg]
SXC_MAX_SIZE:   32.42 [arcmin] diameter
SXC_LOC_SN:     2 sig/noise (pt src in image)
SUN_POSTN:      137.51d {+09h 10m 01s}  +16.32d {+16d 19' 24"}
SUN_DIST:       155.94 [deg]
MOON_POSTN:     163.19d {+10h 52m 45s}  +10.28d {+10d 16' 34"}
MOON_DIST:      135.41 [deg]
MOON_ILLUM:     5 [%]
GAL_COORDS:     4.39,-31.54 [deg] galactic lon,lat of the burst
ECL_COORDS:     297.30,-16.61 [deg] ecliptic lon,lat of the burst
COMMENTS:       Definite GRB.
COMMENTS:       Burst_Validity flag is true.
COMMENTS:       WXM data refined since S/C_Last Notice.
COMMENTS:       SXC data refined since S/C_Last Notice.

GCN notice #3779
E.S. Rykoff, W. Rujopakarn, S.A. Yost, F. Yuan (U Mich) report on behalf of the ROTSE collaboration:
ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to GRB 050807 (HETE trigger 3889). The initial response was delayed due to confusion with the different coordinates received in the first two GCN notices. Targeted observations of the updated GCN position (trigger 3889;3) began at 11:09:51.5 UT, 11.1 minutes after the burst, under excellent conditions. We took 10 5-sec, 10 20-sec and 35 60-sec exposures. These unfiltered images are calibrated relative to USNO A2.0.
The final ground error box (trigger 3889;5) is entirely contained within the initial targeted observation. Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma error box, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 16.3-17.5; we set the following specific limits.
```
start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
11:09:51.5   11:12:7.4     136        17.7   666               Y
11:12:16.8   11:16:55.1    284        18.2   812               Y
11:17:9.9    11:28:34.3    684        18.5   1105              Y
```
GCN notice #3785
M. Maetou, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley, on behalf of the HETE Science Team;
M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, J. Kotoku, M. Matsuoka, Y. Nakagawa, T. Sakamoto, R. Sato, Y. Shirasaki, M. Suzuki, T. Tamagawa, K. Tanaka, Y. Yamamoto, and A. Yoshida, on behalf of the HETE WXM Team;
N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek, J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and HETE Optical-SXC Teams;
M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE FREGATE Team;
report:
The HETE FREGATE, WXM, and SXC instruments detected GRB 050807 (=H3889) at 10:58:45 UT (39525 SOD) on 7 August 2005. The correct WXM flight localization was first reported in a GCN Notice issued at 10:59:19 UT, which was 34s after the burst trigger.
Further WXM and SXC ground localizations were reported in a GCN Notice issued at 13:47:18 UT. The final WXM ground localization can be expressed as an 8 by 48 arcminute box (90% confidence) that is centered at
WXM-Ground: RA = 20h 13m 27s, DEC = -36d 57' 06" (J2000)
and defined by the corners:
```
RA = 20h 13m 16s, DEC = -37d 21' 43"
RA = 20h 12m 40s, DEC = -37d 18' 54"
RA = 20h 13m 38s, DEC = -36d 32' 31"
RA = 20h 14m 14s, DEC = -36d 35' 20".
```
The SXC localization could only be localized along one axis, and hence yields a 3 by 32 arcminute box that is centered at
SXC-Ground: RA = 20h 13m 27s, DEC = -36d 56' 12" (J2000)
and defined by the corners:
```
RA = 20h 13m 39s, DEC = -36d 40' 23"
RA = 20h 13m 00s, DEC = -37d 11' 20"
RA = 20h 13m 14s, DEC = -37d 12' 18"
RA = 20h 13m 54s, DEC = -36d 40' 52".
```
The burst has a duration T_90 of ~55 seconds in 6-40 keV and 6-80 keV, and a T_90 of ~28 seconds in 30-400 keV. Preliminary spectral analyses show the 2-30 keV fluence of GRB 050807 to be 1.3 x 10-6 ergs cm-2 and the 30-400 keV fluence to be 2.2 x 10-6 ergs cm-2. Thus, GRB 050807 is classified as an "X-ray-rich" GRB.
A light curve, skymap, and spectral information for GRB 050807 are provided at the following URL:
http://space.mit.edu/HETE/Bursts/GRB050807
This message may be cited.

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Jochen Greiner, last update: 12-Aug-2005 [Disclaimer]