- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:08:08 UT
NOTICE_TYPE: HETE S/C_Alert
TRIGGER_NUM: 3950, Seq_Num: 1
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_LONG: 136 [deg East]
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_ILLUM: 73 [%]
COMMENTS: No s/c ACS pointing info available yet.
COMMENTS: Probable GRB.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:08:43 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 2
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.937d {+23h 55m 45s} (J2000),
359.012d {+23h 56m 03s} (current),
358.299d {+23h 53m 12s} (1950)
WXM_CNTR_DEC: +19.669d {+19d 40' 08"} (J2000),
+19.701d {+19d 42' 05"} (current),
+19.391d {+19d 23' 26"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 17 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 15.5 Y= 7.0 [sig/noise]
WXM_LC_SN: X= 20.7 Y= 7.5 [sig/noise]
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.60 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.80 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.38,-41.30 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.14,18.41 [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 NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:08:56 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 3
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.943d {+23h 55m 46s} (J2000),
359.017d {+23h 56m 04s} (current),
358.305d {+23h 53m 13s} (1950)
WXM_CNTR_DEC: +19.654d {+19d 39' 13"} (J2000),
+19.686d {+19d 41' 09"} (current),
+19.375d {+19d 22' 31"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 19 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 18.0 Y= 8.0 [sig/noise]
WXM_LC_SN: X= 22.7 Y= 8.0 [sig/noise]
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.61 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.80 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.38,-41.31 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.13,18.39 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:09:57 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 4
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.943d {+23h 55m 46s} (J2000),
359.017d {+23h 56m 04s} (current),
358.305d {+23h 53m 13s} (1950)
WXM_CNTR_DEC: +19.654d {+19d 39' 13"} (J2000),
+19.686d {+19d 41' 09"} (current),
+19.375d {+19d 22' 31"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 19 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 18.0 Y= 8.0 [sig/noise]
WXM_LC_SN: X= 22.7 Y= 8.0 [sig/noise]
SXC_CNTR_RA: 358.992d {+23h 55m 58s} (J2000),
359.067d {+23h 56m 16s} (current),
358.354d {+23h 53m 25s} (1950)
SXC_CNTR_DEC: +19.621d {+19d 37' 15"} (J2000),
+19.653d {+19d 39' 11"} (current),
+19.342d {+19d 20' 33"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.66 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.36 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.34 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:10:12 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 5
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.943d {+23h 55m 46s} (J2000),
359.017d {+23h 56m 04s} (current),
358.305d {+23h 53m 13s} (1950)
WXM_CNTR_DEC: +19.654d {+19d 39' 13"} (J2000),
+19.686d {+19d 41' 09"} (current),
+19.375d {+19d 22' 31"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 19 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 18.0 Y= 8.0 [sig/noise]
WXM_LC_SN: X= 22.7 Y= 8.0 [sig/noise]
SXC_CNTR_RA: 359.000d {+23h 56m 00s} (J2000),
359.075d {+23h 56m 18s} (current),
358.362d {+23h 53m 27s} (1950)
SXC_CNTR_DEC: +19.597d {+19d 35' 51"} (J2000),
+19.630d {+19d 37' 47"} (current),
+19.319d {+19d 19' 09"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.67 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.38 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.32 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:10:22 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 6
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.932d {+23h 55m 44s} (J2000),
359.006d {+23h 56m 01s} (current),
358.294d {+23h 53m 11s} (1950)
WXM_CNTR_DEC: +19.684d {+19d 41' 04"} (J2000),
+19.717d {+19d 43' 00"} (current),
+19.406d {+19d 24' 22"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 20 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 18.0 Y= 9.0 [sig/noise]
WXM_LC_SN: X= 25.5 Y= 9.5 [sig/noise]
SXC_CNTR_RA: 359.000d {+23h 56m 00s} (J2000),
359.075d {+23h 56m 18s} (current),
358.362d {+23h 53m 27s} (1950)
SXC_CNTR_DEC: +19.597d {+19d 35' 51"} (J2000),
+19.630d {+19d 37' 47"} (current),
+19.319d {+19d 19' 09"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.67 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.38 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.32 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:11:27 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 7
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.921d {+23h 55m 41s} (J2000),
358.995d {+23h 55m 59s} (current),
358.283d {+23h 53m 08s} (1950)
WXM_CNTR_DEC: +19.663d {+19d 39' 46"} (J2000),
+19.695d {+19d 41' 43"} (current),
+19.385d {+19d 23' 04"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 9 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 9.0 Y= 4.2 [sig/noise]
WXM_LC_SN: X= 10.2 Y= 4.0 [sig/noise]
SXC_CNTR_RA: 358.992d {+23h 55m 58s} (J2000),
359.067d {+23h 56m 16s} (current),
358.354d {+23h 53m 25s} (1950)
SXC_CNTR_DEC: +19.621d {+19d 37' 15"} (J2000),
+19.653d {+19d 39' 11"} (current),
+19.342d {+19d 20' 33"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SXC_CNTR_RA: 358.992d {+23h 55m 58s} (J2000),
359.067d {+23h 56m 16s} (current),
358.354d {+23h 53m 25s} (1950)
SXC_CNTR_DEC: +19.621d {+19d 37' 15"} (J2000),
+19.653d {+19d 39' 11"} (current),
+19.342d {+19d 20' 33"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.66 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.36 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.34 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:11:32 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 8
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 118 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.921d {+23h 55m 41s} (J2000),
358.995d {+23h 55m 59s} (current),
358.283d {+23h 53m 08s} (1950)
WXM_CNTR_DEC: +19.663d {+19d 39' 46"} (J2000),
+19.695d {+19d 41' 43"} (current),
+19.385d {+19d 23' 04"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 9 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 9.0 Y= 4.2 [sig/noise]
WXM_LC_SN: X= 10.2 Y= 4.0 [sig/noise]
SXC_CNTR_RA: 359.000d {+23h 56m 00s} (J2000),
359.075d {+23h 56m 18s} (current),
358.362d {+23h 53m 27s} (1950)
SXC_CNTR_DEC: +19.597d {+19d 35' 51"} (J2000),
+19.630d {+19d 37' 47"} (current),
+19.319d {+19d 19' 09"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.67 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.38 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.32 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:11:51 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 3950, Seq_Num: 9
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 155 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.970d {+23h 55m 53s} (J2000),
359.044d {+23h 56m 11s} (current),
358.332d {+23h 53m 20s} (1950)
WXM_CNTR_DEC: +19.629d {+19d 37' 43"} (J2000),
+19.661d {+19d 39' 40"} (current),
+19.350d {+19d 21' 01"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 16 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 15.2 Y= 6.2 [sig/noise]
WXM_LC_SN: X= 17.0 Y= 6.0 [sig/noise]
SXC_CNTR_RA: 359.000d {+23h 56m 00s} (J2000),
359.075d {+23h 56m 18s} (current),
358.362d {+23h 53m 27s} (1950)
SXC_CNTR_DEC: +19.597d {+19d 35' 51"} (J2000),
+19.630d {+19d 37' 47"} (current),
+19.319d {+19d 19' 09"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.67 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.38 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.32 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sat 22 Oct 05 13:13:27 UT
NOTICE_TYPE: HETE S/C_Last
TRIGGER_NUM: 3950, Seq_Num: 10
GRB_DATE: 13665 TJD; 295 DOY; 05/10/22
GRB_TIME: 47278.49 SOD {13:07:58.49} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 155 [cnts/s] on a 5.200 [sec] timescale
SC_-Z_RA: 16 [deg]
SC_-Z_DEC: 11 [deg]
SC_LONG: 136 [deg East]
WXM_CNTR_RA: 358.970d {+23h 55m 53s} (J2000),
359.044d {+23h 56m 11s} (current),
358.332d {+23h 53m 20s} (1950)
WXM_CNTR_DEC: +19.629d {+19d 37' 43"} (J2000),
+19.661d {+19d 39' 40"} (current),
+19.350d {+19d 21' 01"} (1950)
WXM_MAX_SIZE: 28.00 [arcmin] diameter
WXM_LOC_SN: 16 sig/noise (pt src in image)
WXM_IMAGE_SN: X= 15.2 Y= 6.2 [sig/noise]
WXM_LC_SN: X= 17.0 Y= 6.0 [sig/noise]
SXC_CNTR_RA: 359.000d {+23h 56m 00s} (J2000),
359.075d {+23h 56m 18s} (current),
358.362d {+23h 53m 27s} (1950)
SXC_CNTR_DEC: +19.597d {+19d 35' 51"} (J2000),
+19.630d {+19d 37' 47"} (current),
+19.319d {+19d 19' 09"} (1950)
SXC_MAX_SIZE: 5.00 [arcmin] diameter
SXC_LOC_SN: 2 sig/noise (pt src in image)
SUN_POSTN: 207.18d {+13h 48m 43s} -11.20d {-11d 12' 01"}
SUN_DIST: 151.67 [deg]
MOON_POSTN: 91.50d {+06h 06m 01s} +28.58d {+28d 34' 49"}
MOON_DIST: 82.78 [deg]
MOON_ILLUM: 73 [%]
GAL_COORDS: 105.43,-41.38 [deg] galactic lon,lat of the burst
ECL_COORDS: 7.16,18.32 [deg] ecliptic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: SXC error box is circular; not rectangular.
- GCN notice #4130
K. Torii (Osaka U.) reports on behalf of the ART collaboration:
The error region of the HETE-2 GRB 051022 (Trigger number 3950)
was observed by the 14 inch Automated Response Telescope. VRcIc
imaging started at 2005 October 22, 13:09:49 UT (111s after the
trigger) and 60s integration was repeated.
Preliminary analysis of a part of the data does not show a new object
brighter than R~15.8 within the 5' diameter SXC error region (GCN
alert sequence number 10). Further observations and analyses are in
progress.
- GCN notice #4131
J-F Olive, 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,
N. Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka,
Y. Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki,
S. Sugita, M. Suzuki, T. Tamagawa, K. Tanaka, 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-P Dezalay, and K. Hurley, on behalf of the HETE FREGATE
Team;
report:
HETE Fregate, WXM, and SXC detected GRB 051022(=H3590) at 13:07:58 on
22 October 2005. The messages sent from the satellite in real time
indicate that the burst is both valid and unusually bright.
Because of a dropout of the internet connection to our ground station at
Cayenne, additional no data were downlinked at the last contact: if this
dropout persists, we will not have complete spectral and temporal data
from GRB051022 until 19h UT.
The HETE team believes that the coordinates distributed in real time
are correct, and we urge that followup observations of these coordinates
be made.
The localization distributed in real time from the WXM was
RA = 23h 55m 53s, Dec = +19d 37' 43" (J2000)
with a 90% confidence error region of 14' radius.
The localization distributed in real time from the SXC was
RA = 23h 56m 00s, DEC = +19d 35' 51" (J2000)
with a 90% confidence error radius of 2.5 arcminutes.
Since the SXC coordinates cannot be independently verified until after the
full data set is downlinked, we urge imaging of the full WXM error region.
- GCN notice #4132
B. E. Schaefer (Louisiana State University) reports on behalf of the
ROTSE collaboration:
ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to
GRB 051022A (HETE trigger 3950), producing images beginning 6.3 s after
the GCN notice time. An automated response took the first image at
13:08:59.8 UT, 61.3 s after the burst, under fair conditions. We took 10
5-sec, 10 20-sec and 50 60-sec eposures. These unfiltered images are
calibrated relative to USNO A2.0 (R).
Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma error circle, for both single images and coadding into sets of 10.
Individual images have limiting magnitudes ranging from 14.5-17.2; we set
the following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
13:08:59.8 13:11:23.8 144 17.4 61.3 Y
13:39:26.5 13:49:26.5 600 17.9 1888.0 Y
- GCN notice #4133
E.Sonoda,S.Maeno,Y.Tokunaga, M.Yamauchi
(University of Miyazaki)
"We have observed the field covering the SXC error region of
GRB051022(HETE trigger 3950; trigger time 13:07:58.49 UT)
with the unfiltered CCD camera on the 30-cm telescope at
University of Miyazaki.The observation was started 13:09:44 UT
on Oct.22.We have compared our image with the USNO A2.0 catalog.
Preliminary analysis shows there is no new source brighter than 17.7 mag.
in the SXC error region."
- GCN notice #4134
S. B. Cenko (Caltech), D. B. Fox (Penn State), R. McNaught and B. Peterson
(RSAA/ANU) report on behalf of a larger collaboration:
"We have imaged the HETE localization region for GRB 051022 (Graziani, GCN
4131) with the Siding Spring Observatory 40-inch telescope. Our
observations consisted of 4 x 100 s images in R-band, taken at a mean
epoch of 13:23:35 UT (~ 15.6 min after the burst). We find no new sources
inside the SXC error circle when compared to the Digital Sky Survey. Our
limiting magnitude, calculated with respect to several Guide Star Catalog
sources in the field, is ~ R > 20.0."
- GCN notice #4137
GRB 051022 (=H3950): SXC Flight Localization is Valid
K. Tanaka, 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, N.
Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka, Y.
Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki, S.
Sugita, M. Suzuki, T. Tamagawa, 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 team, after reviewing the the real-time messages from HETE
regarding GRB 051022(=H3950), believes that the SXC real-time
localization of this burst is valid. As reported in GCN Notices
beginning 118 seconds after the initial trigger and in GCN Circular
4131, the SXC real-time localization can be described as a circle
centered at
RA = 23h 56m 00s, DEC = +19d 35' 51" (J2000)
with a 90% confidence error radius of 2.5 arcminutes.
This SXC localization corresponds not only to the highest correlation
peak in the WXM error circle, but also to the highest correlation
peak in the entire SXC field-of-view. Therefore GRB 051022 was
sufficiently bright in soft X-rays that the SXC position was
determined independently of the WXM result.
In addition, there is good reason to believe that the duration of GRB
051022 is > 2-4 minutes and that there are periods of low emission
during the X-ray prompt emission. These indications, combined with
the upper limit of R > 20 by Cenko et al (GCN 4134), suggest that
searches at NIR and infrared wavelengths for a high redshift object
in the SXC error region would be of interest.
- GCN notice #4139
K. Hurley and T. Cline, on behalf of the Ulysses and Mars
Odyssey GRB teams,
I. Mitrofanov, S. Charyshnikov, V. Grinkov, A. Kozyrev, M. Litvak,
and A. Sanin, on behalf of the HEND-Odyssey GRB team,
W. Boynton, C. Fellows, K. Harshman, C. Shinohara, and R. Starr,
on behalf of the GRS-Odyssey GRB team, and
E. Mazets and S. Golenetskii, on behalf of the Konus-Wind GRB team,
report:
Mars Odyssey and Konus-Wind observed GRB051022 (=H3950, GCN 4131
and 4137). We have triangulated it to an annulus centered at
RA, Decl(J2000)=47.9138, +16.5422 degrees, whose radius is
46.4533 +/- 0.0684 degrees (3 sigma). The center line of this
annulus passes 0.004 degrees from the HETE SXC position, and
the annulus just encompasses the SXC error circle, without
substantially reducing its area. We also confirm that this
burst was exceptionally bright, and that its duration, as observed
by HEND (>~50 keV), was about 200 s. More details will follow.
- GCN notice #4141
J. Racusin, D. Burrows (PSU), N. Gehrels (GSFC) on behalf of the Swift XRT
team:
XRT began observing the field of HETE discovered GRB051022 (Olive et al.,
GCN 4131) at 16:35:54 UT, approximately 3.5 hours after the trigger.
Using 2 orbits of data, we detect a bright uncatalogued fading X-ray
source at the following coordinates:
RA(J2000): 23 56 4.1
Dec(J2000): +19 36 25.1
with an estimated uncertainty of 4 arcseconds (90% containment), including
corrections for the XRT boresight offset. This position is 67 arcseconds
from the HETE position Tanaka et al. (GCN 4137).
- GCN notice #4143
A. J. Castro-Tirado, A. de Ugarte Postigo (IAA-CSIC,
Granada, Spain), G. Bihain (IAC, La Laguna, Spain),
S. Guziy, S. B. Pandey, M. Jelinek and J. Gorosabel
(IAA-CSIC, Granada, Spain),
report:
"We have observed the HETE-2 error box for GRB 051022
(Graziani et al., GCNC 4131) with the 1.5 m Carlos S=E1nchez
telescope at Tenerife, Spain. 30 min exposures in the J and
Ks-band filters were taken starting on October 22 (01:56 UT,
i.e. 12.8 hr after the GRB). Within the SWIFT X-ray error
box (Racusin et al., GCNC 4141), we detect two objects,
at a coordinates (J2000):
#A RA=3D 23 56 04.10 Dec=3D +19 36 27.9
#B RA=3D 23 56 04.18 Dec =3D+19 36 23.1
Preliminary error is 1.0". Object #A seems to be present in
the DSS-2 (IR). Object #B seems much redder than #A and
marginally consistent with another possible source seen in
the DSS-2 (IR).
Additional observations in the near-IR are requested to
confirm if object #B is the nIR afterglow to GRB 051022.
An ID-chart will be posted at
http://www.iaa.csic.es/~deugarte/GRBs/grb051022.gif
- GCN notice #4145
GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
J. Doty, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley, on=20
behalf of the HETE Science Team;=20
M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani,=20
N. Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka,=20
Y. Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki,=20
S. Sugita, M. Suzuki, T. Tamagawa, K. Tanaka, and A. Yoshida, on behalf=20
of the HETE WXM Team;=20
N. Butler, G. Crew, G. Prigozhin, R. Vanderspek, J. Villasenor,=20
J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga, R. Manchanda,=20
and G. Pizzichini, on behalf of the HETE Operations and HETE=20
Optical-SXC Teams;=20
M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE=20
FREGATE Team;=20
report:
We have performed a spectral analysis of the WXM and FREGATE spectral
data for GRB 051022. Fitting a power-law times exponential (PLE) model
jointly to the WXM and FREGATE spectral data yields a chi^2 of 185 for
139 DOF, while fitting a PLE model with absorption yields a chi^2 of
131 for 138 DOF. Fitting a Band model jointly to the WXM and FREGATE
spectral data also yields a chi^2 of 131 for 138 DOF. These results
show that the data strongly favor a PLE model with absorption over a
PLE model alone, and that a PLE model with absorption gives a=20
satisfactory fit to the data. They also show that the data do not=20
request a Band model with absorption.
The best-fit spectral parameters for the PLE model with absorption are
alpha =3D -1.22+/-0.02, E_peak =3D 306 + 31/-26 keV, and n_H =3D 1.7 =B1 =
0.4
x 10^22 atoms cm^-2. The fluence is (2.2 =B1 0.02) x 10^-5 erg cm^-2=20
in the 2-30 keV energy band and (1.4 =B1 0.02) x 10^-4 erg cm^-2 in the
30-400 keV energy band. The ratio log(S_x/S_g) =3D -1.8, so GRB 051022=20
is a "classical" hard GRB.
- GCN notice #4148
E. Berger and P. Wyatt (Carnegie Observatories) report:
"We observed the error circle of GRB 051022 (GCN 4131) with the PANIC
near-IR camera on the Magellan/Baade telescope starting on 2005 Oct 22.105
UT (13.4 hr after the burst). We obtained a total of 18 min in the J and
K bands. Within the XRT error circle (GCN 4141) we detect a single source
which coincides with source B of Castro-Tirado et al. (GCN 4143). This
source is clearly extended. We also detect source A of Castro-Tirado et
al. but note that this source is located about 1.5" outside of the XRT
error circle and it is also extended."
- GCN notice #4149
Richard Cool (Arizona) reports:
On 23 October 2005 UT, we observed the XRT error circle
or GRB051022 (Racusin et al GCN 4141) with the WIYN
0.9m telescope on Kitt Peak through a Johnson R filter.
We observed the field twice for 60 minutes at mean epochs
JD 2453666.6068 and 2453666.7148. Near the reported XRT
position, we find three sources. An image can be found at
http://mizar.as.arizona.edu/~rcool/grb/grb051022.jpg
Two of these sources, A (R=20.31) and B (R=21.51)
are detected in DSS images, while the third source, C
(R=21.21), is not. Photometry is calibrated relative to
nearby USNO stars. Our sources A and B are consistent with
the positions of sources A and B from Castro-Tirado et al
(GCN 4143).
Object C, which does not appear in DSS images, lies 7" from
the location from the Swift XRT. Source C appears point-like
in our images and is located at
alpha J2000 = 23:56:04.2
delta J2000 = 19:36:32.3
There is a fainter source to the SW of object B, but at
R=22.1, this source is below the detection threshold
of the DSS images, and thus it is unclear if the source
is transient. None of the objects detected appear to
fade between our observational epochs. Of the sources
near the XRT position, object C is the most favorable as
the afterglow from the GRB due to its absence in the DSS
images, but its distance from the XRT localization makes
this interpretation suspect.
This message may be cited.
- GCN notice #4150
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline on behalf of the Konus-Wind team report:
The long intense GRB 051022 (HETE trigger #3590; Graziani, GCN 4131)
triggered Konus-Wind at T0=47305.298 s UT (13:08:25.298)
The total burst duration is ~200 sec.
The time-integrated spectrum of the GRB (from T0 to T0+197.12 sec)
is well fitted (in the 20 keV - 2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ E^(-alpha) * exp(-E/E0)
with alpha = 1.176 +/- 0.038
and E0 = 619 (-61, +71) keV (chi^2 = 55/61 dof).
The peak energy Ep = 510 (-33, +37) keV.
This Ep value is significantly larger than
the Ep=306 (+31, -26) keV derived by HETE (Doty et al., GCN 4145),
while the alpha values are in agreement.
Probably, this discrepancy in Ep is due to the limited
energy range of the FREGATE.
As observed by Konus-Wind the burst had a fluence
2.61(-0.11, +0.06)x10^-4 erg/cm2 and
peak flux on 64-ms time scale (1.00 +/- 0.13)x10^-5 erg/cm2/sec
(both in the 20 keV - 2 MeV energy range).
All the quoted errors are at the 90% confidence level.
- GCN Circular #4152
M. Nysewander, E. Cypriano, A. LaCluyze, M. Bayliss, D. Reichart, A.
Alvarez, P. Ugarte report on behalf of the UNC team of the FUN GRB
Collaboration:
We observed the XRT localization (Racusin et al., GCN 4141) of HETE GRB
051022 (Olive et al., GCN 4131) with 4.1m SOAR beginning 11.2 hours after
the burst, in J and Ks.
We detect both A and B of Castro-Tirado et al. (GCN 4143) and report that
neither appear to be fading in Ks between 11.8 and 14.4 hours after the
burst.
- GCN Circular #4153
J. S. Bloom (UCB) reports:
"We observed the field of GRB051022 (GCN 4131; GCN 4137) with the
PAIRITEL 1.3m starting at 2005-10-23 04:00:34 UTC. In a total
exposure of 1836 seconds we detect in JHKs the three sources (A,B:
Castro-Tirado et al. GCN 4143; C: Cool GCN 4149) near the XRT
position (GCN 4141). We note that only source B is consistent with
the current XRT position. An image has been posted to:
http://astro.berkeley.edu/~jbloom/grb051022_ir.gif
(the XRT position marked as a white circle)
Further observations are planned."
This message may be cited.
- GCN Circular #4154
P. B. Cameron (Caltech) and D. A. Frail (NRAO) report on behalf of the
Caltech-NRAO-Carnegie collaboration:
"We observed the field of GRB 051022 (GCN 4131; GCN 4137) with the Very
Large Array at 8.5 GHz beginning October 24.09 UT. We find a
bright radio source with a flux density of 585 +/- 49 uJy at:
RA(J2000) = 23 56 04.1
DEC(J2000) = +19 36 24.1
Within our current astrometric errors (of order 1 arcsec) the source is
coincident with Source B (GCN 4143). We intend to refine this position
with further observations.
We note that there is a nearby, extended radio source whose centroid
is located 15 arcsec to the northwest that is also detected in the NVSS
survey (Condon et al. 1998, AJ, 115, 1693). However, the point source
is clearly offset from the centroid of this extended emission and is not
visible in the NVSS. We identify this point source as the likely
afterglow from GRB051022.
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."
- GCN Circular #4155
S. Immler (GSFC), A. Retter (PSU), J. Racusin (PSU),
L. Cominsky (Sonoma State U), J. Norris (GSFC)
on behalf of the Swift/UVOT team report:
The Swift-UVOT began observing the field of GRB 051022
(HETE Trigger H3950; Olive et al. GCN 4131) at 2005-10-22
16:34:11, about 3.5 hours after the burst.
Based on comparisons with the DSS catalog, we detect
no source inside the XRT error circle at RA, Dec
23:56:4.1, +19:36:25.1 (J2000) with an uncertainty of
4 arcsec (Racusin et al. GCN 4141) in any of the 5 filters
or in summed V-band exposures down to the following 5-sigma
magnitude upper limits:
Filter T_range(hours) Exp(sec) 5sigUL
V 3.47-3.72 900 19.5
B 5.63-5.65 63 18.9
U 5.38-5.63 900 20.1
W1 3.98-4.36 900 19.3
M2 3.73-3.98 900 20.4
V 6.78-13.48 7914 20.7
where T_range is the time post HETE trigger.
The magnitudes have not been corrected for extinction.
- GCN Circular #4156
A. Gal-Yam (Caltech), E. Berger (OCIW), D. B. Fox (Penn State), A. M.
Soderberg, S. B. Cenko, P. B. Cameron (Caltech) and D. A. Frail (NRAO)
report on behalf of the Caltech-NRAO-Carnegie collaboration:
"We observed galaxy "B" (GCN 4143), located within the XRT error circle of the
HETE GRB 051022 (GCN 4131; 4137; 4141) and coincident with the radio afterglow
detected by Cameron et al. (GCN 4154), using the double spectrograph mounted
on the 200" Hale telescope at Palomar Observatory. Preliminary reduction of
a 3600s-long red spectrum of this galaxy reveals a strong line at observed
wavelength 6736 Angstrom which we identify as OII 3727 at z=0.8. This
identification is supported by weaker detections of OIII 5007 and 4959, as
well as Hbeta and Hgamma. We conclude that the likely host of GRB 051022
is at z=0.8. Further analysis is underway."
- GCN Circular #4157
M. Bremer (IRAM, Grenoble), A. J. Castro-Tirado (IAA-CSIC,
Granada) and R. Neri (IRAM), on behalf of a large collaboration,
report:
"On Oct 23.9 UT we have undertaken millimetre observations (3 mm)
with the Plateau de Bure Interferometer of source "B" (Castro-Tirado
et al., GCNC 4143), related to the HETE-2 GRB 051022 (Graziani
et al., GCNC 4131). We found a ~1 mJy source (4 sigma) at
coordinates:
AR(2000) = 23:56:04.14
Dec(2000) = +19:36:25.4
The astrometrical error is 0.5" (1-sigma), consistent with the position
of source B and the VLA radio counterpart detected on Oct 24.1
(Cameron et al. GCNC 4154).
We will continue to monitor the source. "
- GCN Circular #4158
A.J. van der Horst (University of Amsterdam), E. Rol (University of
Leicester) and R.A.M.J. Wijers (University of Amsterdam) report on behalf
of a larger collaboration:
"We observed the HETE GRB 051022 (GCN 4131) at 4.9 GHz with the Westerbork
Synthesis Radio Telescope on October 23 from 15.34 to 20.34 UT, i.e. 1.09
- 1.30 days after the burst. We detect a radio source with a flux density
of 270 +/- 30 microJy at the position of the bright radio source at 8.5
GHz (GCN 4154). This source is within the Swift XRT error box (GCN 4141),
and coincides with the sources A and B (GCN 4143) within our positional
errors. We also detect the bright nearby NVSS source northwest of the
likely GRB051022 afterglow (GCN 4154), with a flux density of 1382 +/- 30
microJy.
Further observations are planned."
This message may be cited.
- GCN Circular #4161
C. Kouveliotou, S. Patel (NASA/MSFC), E. Rol (University of Leicester)
report on behalf of a larger team:
We have triggered our accepted Chandra Guest Investigation on dark Gamma
Ray Bursts for GRB051022. A CXO observation of 20 ks will commence today
at 21:44:42 UT. We plan to analyze the data by the end of the day and
send out a first source location with at least an aspect solution
uncertainty (0.7"). A more accurate location using astrometry will be
reported as soon as the complete data set is available. We urge follow
up observations of the source in radio and IR.
- GCN Circular #4163
S. Patel, C. Kouveliotou (NASA/MSFC), E. Rol (University of Leicester)
report on behalf of a larger team:
We processed the initial 700 s (on source) of our ongoing Chandra ACIS-S
observation of GRB 051022, which started on October 25, 21:14:20 UT. We
detect an X-ray source consistent with the VLA source location (Cameron
& Frail, GCN # 4154) with a count rate of 0.026 c/s in the entire
Chandra band. The Chandra source location is centered at RA=23h56m4.1s
and DEC= +19deg 36' 23.9". We estimate an error of 0.7" dominated by
the uncertainty in the Chandra aspect solution. A more accurate position
based on astrometry may be possible after the complete observation of 20
ks is available.
We are grateful to the Chandra Data Center for the rapid data
processing, in particular Drs Joy Nichols and Craig Anderson.
- GCN Circular #4164
A. de Ugarte Postigo, F. J. Aceituno and S. Guziy
(IAA-CSIC Granada, Spain), on behalf of a large
collaboration,
report:
"We have performed new astrometric measurements of the host galaxy of
GRB 051022 (Olive et al. GCNC 4131, Castro-Tirado et al. GCNC 4143)
using a deep V-band image taken with the 1.5 m telescope at Observatorio
de Sierra Nevada on Oct 24.9 UT. Coordinates yield (J2000):
AR: 23:56:04.10 Dec:+19:36:24.2
with 0".5 error (based on USNO-A2.0). This is consistent, within errors,
with the positions earlier reported in optical (GCNC 4143), radio
(Cameron et al. GCN 4154), mm (Bremer et al. GCNC 4157) and X-rays
(Patel et al. GCNC 4146)."
- GCN Circular #4165
N. R. Butler (UC-Berkeley), G. R. Ricker (MIT), D. Q. Lamb
(U.Chicago), D. N. Burrows (PSU), J. Racusin (PSU), and N. Gehrels
(GSFC) report:
We have performed spectral and temporal analyses of the first three
Swift XRT ToO follow-up observations of the HETE-2--localized burst
GRB 051022 (Olive et al., GCN 4131; Tanaka et al. 4137; Doty et al.
4145). Localization of the X-ray afterglow of the burst was reported
by Racusin et al. (GCN 4141) based on the first two orbits of XRT
data. The PC mode data that we have analyzed have an effective
exposure of 14.2 ksec for the time period of 12.5 to 182.3 ksec after
the burst. Modeling the count rate decay in the 0.5-10 keV band as a
power-law in time, the best-fit decay index is alpha = 1.33 +/- 0.07.
There is no evidence for a jet break in the XRT data that we have
analyzed. The 0.2-10 keV spectrum is well-fit (Chi2/nu = 189/172) by
a power-law model with absorption. We find n_H = (0.84 +/- 0.07) x
10^22 cm^-2, roughly consistent with the value derived from the
HETE-2 WXM and FREGATE data (Doty et al., GCN 4145) and greater than
the Galactic value in the direction of the burst at the 30-sigma
significance level, using the Likelihood Ratio test (Delta Chi2 = 890
for one additional degree freedom). The photon index is gamma = 2.0
+/- 0.1 and the mean unabsorbed flux is (1.9 +/- 0.1) x 10^-11 erg
cm^-2 s^-1. The spectral parameters do not appear to evolve in time
during the observation.
Assuming the relationship A_V = 0.56 N_H[10^21 cm^-2] + 0.23 found by
Predehl and Schmitt (1995; A&A, 293, 889); the expression for the
extinction curve given by Cardelli, Clayton, and Mathis (1989; ApJ,
345, 245); R_V = 3.1; and a redshift for the burst of z = 0.8
(Gal-Yam et al., GCN 4156), based on the positional coincidence
between the galaxy at this redshift and the IR/optical (Castro-Tirado
et al., GCN 4143; de Ugarte Postigo et al., GCN 4164) and radio
(Cameron and Frail, GCN 4154; van der Horst, Rol, and Wijers, GCN
4158) and X-ray afterglow (Patel, Kouveliotou, and Rol, GCN 4163) of
the burst, we derive the following values for the extinction in
magnitudes in the observer frame: A_V = 8.6 +/- 0.7, A_R = 7.7 +/-
0.6, A_I = 6.5 +/- 0.5, A_J = 3.8 +/- 0.3, A_H = 2.3 +/- 0.2, and
A_Ks = 1.5 +/- 0.1.
[GCN OPS NOTE(26oct05): This is a reissue of GCN Circ 4165 with the
binary-conversion characters removed and the line-break formating fixed.]
- GCN Circular #4169
J. Racusin, J. Kennea, D. Fox, D. Burrows, N. Cucchiara (PSU), P. Schady
(MSSL), A. Wells (U. Leicester), N. Gehrels, T. Sakamoto (GSFC), C.
Kouveliotou (MSFC), S. Patel (MSFC) on behalf of the Swift XRT team:
We have analyzed the observations of the X-ray afterglow (Racusin et al.,
GCN 4141, Butler et al, GCN4165) of GRB 051022 (Olive et al., GCN 4131)
beginning approximately 3.5 hours after its discovery by HETE on October
22 and continuing for 4.8 days. We find the early decay slope of 1.33 +/-
0.07 (Butler et al, GCN 4165) extends to 2.9 +/- 0.2 days after the burst,
after which it steepens to a late time decay slope of 3.6 +/- 0.4.
Further observations are planned.
Given the redshift of 0.8 (Gal-Yam et al., GCN 4156) and the different
measured fluences and Epeak by Konus-Wind (Golenetskii et al., GCN 4150)
and HETE (Doty et al, GCN 4145), assuming n=0.1 cm^-3 and our jet break
time, we calculate the following Eiso, Egamma, and jet opening angles:
HETE:
alpha=-1.2, beta=-10.0, Epeak=306 keV, 2-400 keV fluence=1.6e-4 erg cm-2
Eiso = 3.8e53 erg
Jet opening angle = 4.3 degrees
Egamma = 1.1e51 erg
Konus-Wind:
alpha=-1.2, beta=-10.0, Epeak=510 keV, 20 keV-2 MeV fluence=2.6e-4 erg cm-2
Eiso = 3.1e53 erg
Jet opening angle = 4.4 degrees
Egamma = 9.1e50 erg
- GCN Circular #4170
GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
N. R. Butler (UC-Berkeley), G. R. Ricker (MIT), D. Q. Lamb(U.
Chicago), D. N. Burrows (PSU), J. Racusin (PSU), and N. Gehrels
(GSFC) report:
In our calculation (Butler et al. GCN 4165) of the extinction of the
optical and NIR afterglow of GRB 051022 in the observer frame implied
by the best-fit value of the absorption of the X-ray afterglow
measured by the Swift XRT, we did not take into account the
transformation between the absorption of the X-ray spectrum as
measured in the observer frame and that measured in the rest frame of
the host galaxy. Taking this transformation into account, and using
the same method as that described in Butler et al. (GCN 4165), we
derive the following values for the extinction in magnitudes in the
observer frame: A_V = 41.1 +/- 3.4, A_R = 36.7 +/- 3.0, A_I = 30.9
+/- 2.5, A_J = 17.6 +/- 1.5, A_H = 10.8 +/- 0.9, and A_Ks = 6.8 +/-
0.6.
These values for the extinction are large enough to account for the
failure to detect the afterglow of GRB 051022 in either the optical
(Torii GCN 4130; Schaefer GCN 4132; Sonoda et al., GCN 4133; Cenko et
al., GCN 4134; Cool GCN 4149; Immler et al., GCN 4155) or the NIR
(Castro-Tirado et al., GCN 4143; Berger and Wyatt, GCN 4148:
Nysewander et al., GCN 4152; Bloom GCN 4153), provided that most of
the dust is not destroyed by the burst and/or its afterglow.
- GCN Circular #4181
R. Burenin, D. Denisenko, M. Pavlinsky, R. Sunyaev (IKI), I. Khamitov,
Z. Aslan (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.),
I. Bikmaev, N. Sakhibullin (KSU/AST)
report:
The error box of GRB 051022 (Olive et al., 4131; Tanaka et al., 4137)
was observed with Russian-Turkish 1.5-m telescope (RTT150, Bakyrlytepe,
TUBITAK National Observatory, Turkey) in R, starting at Oct. 22, 16:16
UT, i.e. 3.15 hours after the burst.
The galaxy, where X-ray afterglow was detected with XRT (Racusin et al.,
GCN 4141) and later with Chandra (Patel et al., GCN 4163), appears in
our images as clearly extended source. Its optical flux is stable within
0.1mag during our observations, i.e. till 20:00 UT, therefore we
detected no variable source superimposed on this galaxy.
This message may be cited.
- GCN notice #4184
A. Henden (AAVSO/USNO) reports on behalf of the USNO GRB Team:
We have acquired UBVRcIc all-sky photometry for 23x23arcmin
fields centered on the coordinates of recent GRB localizations
with the USNOFS 1.0-m telescope on 1 or 2 photometric nights.
We are using a new CCD, and so place an additional zeropoint
error of about 0.03mag that should be added in quadrature
to the errors reported in the files listed below.
Stars brighter than V=13.0 are saturated and should be used
with care. We have placed the photometric data on our
anonymous ftp site:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb050505.dat
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051021.dat
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051022.dat
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051028.dat
Since these bursts had identified optical afterglows, we may
improve the photometric calibration on subsequent observing runs.
As always, you should check the dates on the .dat file prior to
final publication to get the latest photometry. There is
a README file on the ftp directory to give you information
about the procedures used to calibrate these fields.
- astro-ph/0605407 from 17 May 2006
Nakagawa: An Optically Dark GRB Observed by HETE-2: GRB 051022
GRB 051022 was detected at 13:07:58 on 22 October 2005 by HETE-2. The
location of GRB 051022 was determined immediately by the flight localization
system. This burst contains multiple pulses and has a rather long duration of
about 190 seconds. The detections of candidate X-ray and radio afterglows were
reported, whereas no optical afterglow was found. The optical spectroscopic
observations of the host galaxy revealed the redshift z = 0.8. Using the data
derived by HETE-2 observation of the prompt emission, we found the absorption
N_H = 8.8 -2.9/+3.1 x 10^22 cm^-2 and the visual extinction A_V = 49 -16/+17
mag in the host galaxy. If this is the case, no detection of any optical
transient would be quite reasonable. The absorption derived by the Swift XRT
observations of the afterglow is fully consistent with those obtained from the
early HETE-2 observation of the prompt emission. Our analysis implies an
interpretation that the absorbing medium could be outside external shock at R ~
10^16 cm, which may be a dusty molecular cloud.
- 0706.1518from 11 Jun 2007
Rol: GRB051022: physical parameters and extinction of a prototype dark burst
Abstract: GRB051022 was undetected to deep limits in early optical observations, but
precise astrometry from radio and X-ray showed that it most likely originated
in a galaxy at z ~ 0.8. We report radio, optical, near infra-red and X-ray
observations of GRB051022. Using the available X-ray and radio data, we model
the afterglow and calculate the energetics of the afterglow, finding it to be
an order of magnitude lower than that of the prompt emission. The broad-band
modeling also allows us to precisely define various other physical parameters
and the minimum required amount of extinction, to explain the absence of an
optical afterglow. Our observations suggest a high extinction, at least 2.8
magnitudes in the infrared (J) and at least 6 magnitudes in the optical (U) in
the host-galaxy restframe. Such high extinctions are unusual for GRBs, and
likely indicate a geometry where our line of sight to the burst passes through
a dusty region in the host that is not directly co-located with the burst
itself.
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