Gamma-ray Burst 020812

(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:    Mon 12 Aug 02 10:50:48 UT
NOTICE_TYPE:    HETE S/C_Alert
TRIGGER_NUM:    2257,   Seq_Num: 1
GRB_DATE:       12498 TJD;   224 DOY;   02/08/12 
GRB_TIME:       38503.98 SOD {10:41:43.98} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     154  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       296 [deg]
SC_-Z_DEC:      -19 [deg]
SC_LONG:        160 [deg East] 
WXM_CNTR_RA:    309.559d {+20h 38m 14s} (J2000),
                309.593d {+20h 38m 22s} (current),
                308.898d {+20h 35m 36s} (1950)
WXM_CNTR_DEC:    -5.279d {-05d 16' 43"} (J2000),
                 -5.270d {-05d 16' 10"} (current),
                 -5.455d {-05d 27' 17"} (1950)
WXM_MAX_SIZE:   60.00 [arcmin] diameter
WXM_LOC_SN:     4 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 2.7 Y= 5.2 [sig/noise]
WXM_LC_SN:      X= 3.2 Y= 2.5 [sig/noise]
SUN_POSTN:      141.98d {+09h 27m 55s}  +14.95d {+14d 57' 06"}
SUN_DIST:       164.44 [deg]
MOON_POSTN:     190.83d {+12h 43m 19s}   +0.41d {+00d 24' 26"}
MOON_DIST:      118.67 [deg] 
MOON_ILLUM:     18 [%]
GAL_COORDS:     40.75,-26.11 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.56,12.77 [deg] ecliptic lon,lat of the burst
COMMENTS:       Probable GRB.
COMMENTS:       WXM error box is circular; not rectangular.
COMMENTS:       WXM S/N is less than a reasonable value.

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Mon 12 Aug 02 10:50:55 UT
NOTICE_TYPE:    HETE S/C_Last  
TRIGGER_NUM:    2257,   Seq_Num: 2
GRB_DATE:       12498 TJD;   224 DOY;   02/08/12 
GRB_TIME:       38503.98 SOD {10:41:43.98} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     154  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       296 [deg]
SC_-Z_DEC:      -19 [deg]
SC_LONG:        160 [deg East] 
WXM_CNTR_RA:    309.559d {+20h 38m 14s} (J2000),
                309.593d {+20h 38m 22s} (current),
                308.898d {+20h 35m 36s} (1950)
WXM_CNTR_DEC:    -5.279d {-05d 16' 43"} (J2000),
                 -5.270d {-05d 16' 10"} (current),
                 -5.455d {-05d 27' 17"} (1950)
WXM_MAX_SIZE:   60.00 [arcmin] diameter
WXM_LOC_SN:     4 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 2.7 Y= 5.2 [sig/noise]
WXM_LC_SN:      X= 3.2 Y= 2.5 [sig/noise]
SUN_POSTN:      141.98d {+09h 27m 55s}  +14.95d {+14d 57' 06"}
SUN_DIST:       164.44 [deg]
MOON_POSTN:     190.83d {+12h 43m 19s}   +0.41d {+00d 24' 26"}
MOON_DIST:      118.67 [deg] 
MOON_ILLUM:     18 [%]
GAL_COORDS:     40.75,-26.11 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.56,12.77 [deg] ecliptic lon,lat of the burst
COMMENTS:       Probable GRB.
COMMENTS:       WXM error box is circular; not rectangular.
COMMENTS:       WXM S/N is less than a reasonable value.

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/HETE BURST POSITION NOTICE
NOTICE_DATE:    Mon 12 Aug 02 13:19:48 UT
NOTICE_TYPE:    HETE Ground Analysis
TRIGGER_NUM:    2257,   Seq_Num: 3
GRB_DATE:       12498 TJD;   224 DOY;   02/08/12 
GRB_TIME:       38503.98 SOD {10:41:43.98} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE:     154  [cnts/s]  on a 1.300 [sec] timescale
SC_-Z_RA:       295 [deg]
SC_-Z_DEC:      -19 [deg]
SC_LONG:        160 [deg East] 
WXM_CNTR_RA:    309.699d {+20h 38m 48s} (J2000),
                309.733d {+20h 38m 56s} (current),
                309.038d {+20h 36m 09s} (1950)
WXM_CNTR_DEC:    -5.393d {-05d 23' 34"} (J2000),
                 -5.384d {-05d 23' 00"} (current),
                 -5.570d {-05d 34' 09"} (1950)
WXM_CORNER1:    309.8260  -5.5850 [deg]
WXM_CORNER2:    309.6580  -5.6100 [deg]
WXM_CORNER3:    309.5720  -5.2009 [deg]
WXM_CORNER4:    309.7389  -5.1760 [deg] 
WXM_MAX_SIZE:   27.58 [arcmin] diameter  
WXM_LOC_SN:     4 sig/noise (pt src in image)
WXM_IMAGE_SN:   X= 3.8 Y= 3.3 [sig/noise]
WXM_LC_SN:      X= 6.3 Y= 8.3 [sig/noise]
SUN_POSTN:      141.98d {+09h 27m 55s}  +14.95d {+14d 57' 06"}
SUN_DIST:       164.62 [deg]
MOON_POSTN:     190.83d {+12h 43m 19s}   +0.41d {+00d 24' 26"}
MOON_DIST:      118.81 [deg]
MOON_ILLUM:     18 [%]
GAL_COORDS:     40.71,-26.29 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.67,12.62 [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.

GCN notice #1468
G. Ricker, J-L Atteia, N. Kawai, D. Lamb, and S. Woosley on behalf of the HETE Science Team;
J. Doty, R. Vanderspek, J. Villasenor, G. Crew,G. Monnelly, N. Butler, T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and HETE Optical-SXC Teams;
Y. Shirasaki, C. Graziani, M. Matsuoka, T. Tamagawa, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, and T. Donaghy, on behalf of the HETE WXM Team;
M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf of the HETE FREGATE Team;
write:
At 10:41:43.98 UTC (38503.98 s UT) on 12 Aug 2002, the HETE FREGATE and WXM instruments detected event H2257, a long GRB. The WXM flight localization was correct and was reported in a GCN Position Notice at 10:50:48 UT, 9 min 4 sec after the burst. Ground analysis produced a refined location, which was reported in a GCN Position Notice at 13:19:48 UT, 158 minutes after the burst. This location can be expressed as a 90% confidence rectangle that is 10 arcminutes by 25 arcminutes and is centered at
RA = 20h 38m 48s, Dec = -05o 23' 34" (J2000).
The corners of the location rectangle lie at the following J2000 coordinates:
```
RA = 20h 39m 18s, Dec = -05o 35' 06"
RA = 20h 38m 38s, Dec = -05o 36' 36"
RA = 20h 38m 17s, Dec = -05o 12' 03"
RA = 20h 38m 57s, Dec = -05o 10' 34".
```
In the FREGATE 8-40 keV band, the burst had a duration of ~20 seconds. A total of 1741 net counts were detected in the 8-40 keV band during this interval, corresponding to a fluence of ~3.1 x 10-7 ergs cm-2. The peak flux averaged over 0.5 s was 4.9 x 10-8 ergs cm-2 s-1 (i.e., 1.6 x Crab flux). In the WXM 2-25 keV band, the burst had a duration of ~20 seconds. The WXM localization SNR was 6.3 in the X-detector and 8.3 in the Y-detector.
Further information (including a light curve) for GRB020812 is provided
at the following URL:
http://space.mit.edu/HETE/Bursts/
This message is citable.
GCN notice #1469
H. Ohashi, T. Kato, T. Senda, H. Mii, K. Mizuno, Y. Yasaka (Kyoto Univ.) report on behalf of VSNET-grb collaboration:
"We have observed the field of GRB 020812 (HETE trigger 2257) with R band exposures using the 60-cm RC telescope at Ouda station starting at Aug. 12 11:09 UT (28 min after the burst). We imaged the field (field size 20 arcmin) centered at the first localization (HETE #2257, Seq_Num 2) until 13:30 UT. We have been imaging the field centered at the second localization (HETE #2257, Seq_Num 3) since 13:33 UT. Preliminary visual inspection of the images has not revealed a new object down to R=18. Further analysis and observation are in progress."
This message may be cited.
GCN notice #1479
A.Pozanenko (IKI), S.Bondar' (Kosmoten), G.Beskin (SAO) and V. Rumyantsev (CrAO) report:
We have observed the entire error box of GRB 020127 / HETE #1902 with 600mm automated telescope (T600 of Kosmoten observatory. Observation started after HETE Ground Analysis (HETE 2257, Seq_Num: 3). Unfiltered mosaic images were obtained on Aug 12 18:52 (UT) with fixed image exposure 2.56 sec. Limiting magnitude of the observation is about 16.5.
We have found a new object which is not present on DSS. The coordinates of the object are:
RA= 20h38m51s DEC= -05o31'14" (J2000)
with uncertainty of 4" in both coordinates. Using USNO-A2.0 we estimate brightness of the object about 14.5 m.
This message is citable.
GCN notice #1482
There was a misprint in GCN 1479 in the name of GRB. The corrected text is below.
A.Pozanenko (IKI), S.Bondar' (Kosmoten), G.Beskin (SAO) and V. Rumyantsev (CrAO) report:
We have observed the entire error box of GRB020812 with 600mm automated telescope TT600 of Kosmoten observatory. Observation started after HETE Ground Analysis (HETE 2257, Seq_Num: 3). Unfiltered mosaic images were obtained on Aug 12 between 18:52 - 18:55 (UT) with image exposure of 2.56 sec. Limiting magnitude of the observation is about 16.5.
We have found a new object, which is not present on DSS. The coordinates of the object are:
RA= 20h38m51s DEC= -05o31'14" (J2000)
with uncertainty of 4" in both coordinates. Using USNO-A2.0 we estimate brightness of the object about 14.5 m. We have no images taken later, so the nature of the object in unclear.
GCN notice #1486
A. Piccioni, C. Bartolini, I.Bruni, A. De Blasi, A. Guarnieri (Bologna University and Bologna Astronomical Observatory), F. Giovannelli (Istituto di Astrofisica Spaziale-CNR) and G. Pizzichini (IASF-CNR, Sezione di Bologna) report:
On 2002 August 12, 20h18m35s UT we started observations of the error box of GRB 020812 (GCN 1468) with the 152 cm telescope in Loiano, (R band, 2x600 + 2x780 + 10x900 sec exposures). Observations of the field ended on August 13, 01h49m42s UT. Coverage of the entire error box was performed two times. By visual inspection in our frames there is no new source brighter than the limit of DssII. The field containing the brigt object mentioned in GCN 1479 was imaged on August 12, 21h17m54s UT, i.e. 2.5 hours after the detection of the possible afterglow candidate. Our frame, somewhat deeper than DssII, does not reveal any new object. Our images can be retrieved by sftp at 'ermione.bo.astro.it', username 'publicGRB', password 'GRB_bo', starting on August 16.
This message may be cited.
GCN notice #1489
T. Kawabata (BAO), T. Morishita (OPU), T. Hatayama T. Miyata, S. Nishiura, H. Mito on behalf of KISO GRB team, Y. Urata (Titech / RIKEN), H. Yamaoka (Univ. Kyushu) report:
We have imaged the entire error box of GRB020812 (G. Ricker et al.= GCN1468 ) with the Bisei Astronomical Observatory (BAO) 1.01 m telescope (FOV 7.8'x5.2') with 12 nonfilter pointing observations starting at Aug 12 14:00 UT and at Aug 13 14:30 UT.
The optical transient candidate reported by A. Pozanenko et al. (GCN1481) was not detected at either epoch with a limit comparable to that of the DSS2 red image, or approximately R=19 estimated by comparison with USNO-A2.0 (U0825_18548790).
We also covered the entire error box with the KISO observatory 1.05 m Schmidt telescope (FOV 50'x50') starting at Aug 12 15:08 UT. The OT candidate was not detected.
Following is the summary of the observations.
```
   Site   Time (UT)  Exptime  Filter Limit mag.
   BAO     14:20      60 s    no     19
   BAO     14:48      60 s    no     19
   KISO    15:08     900 s     R     17
```
Further analysis is in progress.
GCN notice #1493
T. Kawabata (BAO), T. Morishita (OPU), T. Hatayama (BAO visitor), Y. Urata (Titech / RIKEN), and H. Yamaoka (Kyushu U) report:
"A full analysis of Bisei Astronomical Observatory (BAO) images (GCN 1489) of GRB 020812 was performed. The entire error box was imaged five times with 12 no-filter pointing observations (60 seconds exposure each) by 1.01-m BAO telescope.
```
 set     Time(UT) 
  1  Aug 12 14:00-14:28
  2  Aug 12 14:31-14:55
  3  Aug 13 15:19-15:40
  4  Aug 13 15:43-16:02
  5  Aug 13 16:07-16:28
```
The limiting magnitude for each images is mag 19.1 (3 sigma, compared with USNO-A2.0 red magnitudes), although some images are poor because of thin clouds.
Comparison with DSS II red images, no new object was detected down to the limiting magnitude. Also, the comparison between our observations, no notable variable object was detected."
This message may be cited.
GCN notice #1496
Subject: GRB020812: optical observations
E.Pavlenko (CrAO), V.Doroshenko (GAISh), S.Sergeev (CrAO), O.Dudka (CrAO), A.Baklanov (Odessa Univ.), N.Primak (Kiev Univ.), and A. Pozanenko (IKI) report:
We have observed the field 15'x15' of GRB 020812 (HETE trigger 2257, Seq. 3) at two telescopes of the Crimean Astrophysical Observatory. The optical candidate was not detected. Following is the summary of observations.
```
Telescope  time (UT)   Exposure  Filter  Limit. mag
70 cm     Aug 12 20:18    120 c     R       17.5
38 cm     Aug.12 20:57    300 c     R       17
```
This message may be cited
GCN notice #1499
A. Arkharov (1), V. Larionov (2), A. Di Paola (3), A. Antonelli (3)
1) Pulkovo Observatory (RU) 2) St.Petersburg University (RU) 3) Rome Astronomical Observatory (IT)
on the behalf of the GROAR Team, report:
We have imaged the error box of the GRB020812 (G. Ricker et al. GCN 1468) from Campo Imperatore Observatory with the 1.1 meters AZT-24 telescope and the SWIRCAM Near Infra-Red camera. Observations started on 12-08-2002 20:19:44 UT and ended on 12-08-2002 01:27:10 UT.
About 40% of the error box has been imaged at IR wavelengths both in J and K bands. No new source has been detected and the counterpart reported by A.Pozanenko (GCN 1481) is not detected down to a limiting magnitude of J 18 and K 17.
The images can be found at http://grb.mporzio.astro.it.
This message may be cited.
GCN notice #1515
H. Ohashi, T. Kato, T. Senda, H. Mii, K. Mizuno, Y. Yasaka (Kyoto U) and H. Yamaoka (Kyushu U) report on behalf of VSNET-grb collaboration:
"We have performed a full analysis of the R band images of GRB 020812 field taken at Ouda (GCN 1469). Three fields of view (14 arcminutes square) were observed, each of which covered a part of HETE WXM error box (GCN 1468) ( http://www.rc.kyushu-u.ac.jp/~yamaoka/GRB020812/FOVouda.gif). The limiting magnitudes are measured by compareing with USNO-A2.0 red magnitudes. "Coverage" shows the percentage of covered area of the HETE WXM error box.
```
FOV        1               2               3
center   20:38:28.8     20:38:21.0      20:38:53.3      R.A.
(J2000) -05:17:58       -05:17:24       -05:23:45       Dec.
epoch    11:08-12:03    12:05-13:27     13:34-16:59     Aug. 12 UT +
exp.     38             73              156             minutes
lim.mag  18.9           20.2            21.2            in R
coverage 48%            30%             58%
remark   twilight
 
```
By the comparison with DSS 2 red image, no new source brighter than the limit of DSS 2 is detected.
This message may be cited.
GCN notice #1521
M. Uemura, R. Ishioka, T. Kato (Kyoto U) and H. Yamaoka (Kyushu U) report on behalf of VSNET-grb collaboration:
"We have performed a full analysis of the unfiltered images of GRB 020812 field taken at Kyoto University. A 30-cm telescope observed the central part of the on-board HETE WXM error box, and a 25-cm telescope observed three fields of view, each of which covered a part of HETE WXM error box (GCN 1468) (http://www.rc.kyushu-u.ac.jp/~yamaoka/GRB020812/FOVkyoto.gif). The limiting magnitudes are measured by compareing with USNO-A2.0 red magnitudes.
```
FOV	  25-cm 1	 25-cm 2	 25-cm 3 	30-cm 
epoch	 11:36-13:25	13:27-13:57	13:57-15:32	11:40-13:26 Aug. 12 UT+
exp.	 85		25.5		80		83.5	minutes
lim.mag  18.7		18.6		18.8		19.1	in R
```
By comparison with DSS 2 red image and Ouda images (GCN 1515), no new source brighter than the limits nor notable variable is detected."
This message may be cited.
GCN notice #1522
G. Masi, F. Mallia and U. Tagliaferri (Campo Catino Astronomical Observatory, Italy) report:
On Aug. 14.069 2002 UT, we imaged the field around the position provided by Pozanenko et al. (GCN 1479) with the 0.8m-f/8 + CCD from Campo Catino Astronomical Observatory. The R-images, covering a field of about 5.5' x 5.5', do show nothing obvious down to R = 19.0 (based on USNO A2.0).
This message may be cited.
GCN notice #1527
G.Beskin, A.Birjukov, S.Koposov, O.Spiridonova (SAO), S.Bondar' (Kosmoten) and A.Pozanenko (IKI) report:
We have observed the error box of GRB020812 (HETE trigger 2257, GCN 1468) with Zeiss-1000 telescope of Special Astrophysical Observatory (SAO) on August 13 20:01 UT. R-band image of 6.9'x 6.9' with exposure time of 303 sec was centered to coordinates reported in GCN 1481. The limiting magnitude of the image is R~22 (3 sigma). No new objects were found in comparison with DSS2.
The image may be found at http://grb.rssi.ru/GRB020812
This message may be cited.

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Jochen Greiner, last update: 28-Aug-2002 [Disclaimer]