GRB 030227
GCN Circular 1936
Subject
GRB 030227: Optical limit at RIKEN
Date
2003-03-10T11:14:26Z (23 years ago)
From
Ken ichi Torii at RIKEN <torii@crab.riken.go.jp>
K. Torii (RIKEN), T. Kato (Kyoto U.), and H. Yamaoka (Kyushu U.)
report:
In response to the IBAS alert message (INTEGRAL Trigger #214), the
entire error region of GRB 030227 (Gotz, et al., GCN 1895 and 1896)
was observed by the automated system at RIKEN (0.25-m f/6.8 reflector
equipped with unfiltered CCD AP6E). The observation started at 2003
Feb. 27 09:31:39 UT (49 minutes after the burst). After 73 frames of
40-s integration were acquired, 60-s integration was repeated.
We have applied PSF photometry to these data. The optical transient
(Casto-Tirado, et al., GCN 1904; Soderberg, et al., GCN 1907; Berger,
et al., GCN 1910) is not significantly detected.
By using Henden's sequence (GCN 1917), we preliminarily estimate a
star at (04:57:16.351, +20:27:00.66) (USNO-A2.0 position) as Rc = 11.7
and derive 3-sigma upper limits for the optical transient as follows.
-------------------------------------------------------
Rc Mag. / Mean Epoch (UT) / (Start - End) / Integration
-------------------------------------------------------
>20.3 09:41:03 (09:31:39 - 09:50:26) 40-s x 24 frames
>20.4 10:08:45 (09:50:31 - 10:26:58) 40-s x 49 frames
-------------------------------------------------------
GCN Circular 1926
Subject
GRB 030227: Optical observations
Date
2003-03-05T16:33:21Z (23 years ago)
From
Vasilij Rumjantsev at CrAO <rum@crao.crimea.ua>
E. Pavlenko (CrAO), V. Rumyantsev (CrAO), A.Pozanenko (IKI)
We have observed the error box of GRB030227 (GCN 1896) in CrAO. Several
images were obtained with AT-64 (unfiltered) and AT-38 (R-band) telescopes.
No OT was found in place of the source S1-A (GCN 1907, 1910). Using
photometry by A. Henden (GCN 1917) we estimate the limiting magnitudes
(S/N=3) as following
Start time (UT) telescope exposure limiting mag.
Feb 27 16:58:10 AT-38 3x200 s 19.5 (R)
Feb 27 16:58:24 AT-64 5x120 s 19.2 (~R)
This message may be cited.
GCN Circular 1922
Subject
GRB030227, optical observations
Date
2003-03-04T21:49:32Z (23 years ago)
From
Rene Hudec at AIO <rhudec@asu.cas.cz>
R. Hudec, M. Jelinek (Astronomical Institute Ondrejov), M. Tichy, J.
Ticha (Klet Observatory) report:
We have observed the position of GRB030227 with the 1.06 m KLENOT
telescope + CCD at the Klet
observatory. 60s unfiltered exposure with limiting magnitude 21
according to GSC2 has been obtained
at 18:26 UT, February 27, 2003.
No new objects down to magnitude 21 were found in the GRB error box in
comparison with deeper
published images.
GCN Circular 1920
Subject
GRB030227: Kiso optical upper limit
Date
2003-03-04T09:26:51Z (23 years ago)
From
Yuji Urata at RIKEN <urata@crab.riken.go.jp>
Y. Urata, T. Aoki on behalf of the Kiso GRB team
and H. Izumiura (OAO) report:
We re-examine our multi-band data obtained at Kiso observatory
starting at 2.1 hour after the burst (Izumiura et al. GCN1900).
We could not detect the optical afterglow ( S1-A ; Castro-Tirado et
al. GCN 1904, Soderberg et al. GCN 1907, Berger et al. GCN 1910,
Gorosabel et al. GCN 1915) down to limiting magnitudes estimated by
comparison with the result of field photometry by Henden (GCN1917).
Our data:
Date Time (UT) Band Exposure Limiting mag.(SN=3)
02-27 10:43-11:03 R 300s x 3 21.1
11:05-11:24 I 300s x 3 20.1
11:27-11:32 V 300s x 3 20.9
11:49-12:08 B 300s x 3 21.7
12:44-12:54 R 600s 20.6
This message may be cited.
GCN Circular 1917
Subject
GRB030227, BVRcIc field photometry
Date
2003-03-03T18:20:20Z (23 years ago)
From
Arne A. Henden at USNO/USRA <aah@nofs.navy.mil>
A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:
We have acquired BVRcIc all-sky photometry for
a 20x20 arcmin field centered at the coordinates
for the optical transient (Castro-Tirado et al., GCN 1904)
associated with the INTEGRAL burst GRB030227 (Gotz et al.,
GCN 1895, 1896) with the USNOFS 1.0-m telescope on one
photometric night. Stars brighter than V=13.5 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/grb030227.dat
The astrometry in this file is based on linear plate solutions
with respect to UCAC2. The external errors are less than 100mas.
The estimated external photometric error is 0.03mag.
This calibration will be extended with additional nights to
ensure against a systematic zeropoint error, but current
weather forecasts indicate that this may be a week or two.
We will not be performing U-band calibration unless requested.
As always, you should check the dates on the .dat file prior
to final publication to get the latest photometry.
GCN Circular 1915
Subject
GRB 030227 optical afterglow
Date
2003-03-03T08:01:13Z (23 years ago)
From
Javier Gorosabel at LAEFF-INTA, Madrid <jgu@laeff.esa.es>
J. Gorosabel (IAA-CSIC/STScI), A.J. Castro-Tirado,
D. Reverte, J. V�lchez (IAA-CSIC),
J.M. Castro Cer�n (STScI), A. de Ugarte Postigo,
S. Guziy (IAA-CSIC) and S. Mart�nez (Univ. de Valencia)
report:
"We have obtained a second epoch observation
covering the INTEGRAL error box for GRB 030227
(Gotz et al. GCN Circ. 1895, 1896) with the 2.5 m
Isaac Newton Telescope at the Observatorio del Roque de
los Muchachos (Canary Islands, Spain). Three R-band
frames (600 s exposure time each) have been obtained
on Feb 28.95 UT. Within the X-ray source error box
given by XMM-Newton (Loiseau et al. GCN Circ. 1901),
the object suggested by Castro-Tirado et al. (GCN Circ. 1904)
as a possible afterglow candidate with R = 23.3
(this value supersedes the one given in GCN Circ. 1904)
is not detected down to R = 24.2. This confirms its
relationship to GRB 030227, also proposed by Soderberg
et al. (GCN Circ. 1906) and Berger et al. (GCN Circ. 1910)."
This message can be quoted.
GCN Circular 1910
Subject
GRB 030227: Confirmed Optical Afterglow (S1-A)
Date
2003-03-01T06:59:18Z (23 years ago)
From
Edo Berger at Caltech <ejb@astro.caltech.edu>
E. Berger, S. Kulkarni, A. Soderberg, and D. Fox (Caltech) report on
behalf of a larger GRB collaboration:
"We have re-imaged the field of GRB 030227 with ESI on the Keck II
telescope starting on Mar 1.25 UT. In the 6" localization of the XMM
source S1 (Loiseau et al. GCN 1901) we again detect the two sources S1-A
(Castro-Tirado et al. GCN 1904; Soderberg et al. GCN 1907) and S1-B (GCN
1907). We find that source S1-A has continued to fade (as t^-1),
confirming it as the optical afterglow of GRB 0320227 as suggested by
Soderberg et al. (GCN 1907).
The candidate of Ofek and Gal-Yam (GCN 1903) has remained constant between
last night and tonight with a magnitude of about 22.1."
This message may be cited.
GCN Circular 1907
Subject
GRB 030227: fading of candidate optical afterglow 'S1-A'
Date
2003-02-28T10:02:17Z (23 years ago)
From
Alicia Soderberg at Caltech <ams@astro.caltech.edu>
A. M. Soderberg, D. Fox, S. Kulkarni, and E. Berger (Caltech) report on
behalf of a larger GRB collaboration:
"We have imaged the field of GRB 030227 with ESI on Keck II beginning
at Feb 28.242 UT in various optical bands. In the R-band image, we
find two sources in the 3-arcminute (radius) error circle of the XMM
source 'S1' (Loiseau et al. GCN 1901), hereafter S1-A and S1-B:
'S1-A' 04:57:33.05 +20:29:04.9 (J2000)
'S1-B' 04:57:32.80 +20:29:06.2 (J2000)
The positions are accurate to 0.3" and are based on 19 stars from the
GSC-II catalog.
The source S1-A is clearly seen in the Isaac Newton Telescope (INT)
R-band image presented by Castro-Tirado et al. (GCN 1904). We find a
magnitude of R ~ 23.5 for S1-A and R ~ 25.0 for S1-B relative to the
above set of GSC-II stars. Comparison with Castro-Tirado et al. (GCN
1904) indicates that the source has faded by ~1.0 magnitudes since
Feb. 27.872 UT. This fading is visually confirmed by comparing our
image (see URL below) with the INT image. We note that the candidate
of Ofek and Gal-Yam (GCN 1903) may also be fading; with the same
calibration we measure R ~ 22.1 for their source and R ~ 18.1 for
their star A.
Given the coincidence of S1-A with the X-ray source and its fading
behavior we suggest that it is the optical afterglow of GRB 030227.
Our image can be found at:
http://www.astro.caltech.edu/~ams/grb030227/
Analysis of other candidates is in progress."
GCN Circular 1906
Subject
GRB030227:Optical observations
Date
2003-02-28T04:20:22Z (23 years ago)
From
Gerald Bourban at Geneva Observatory <grb@obs.unige.ch>
G. Bourban, F. Carrier, A. D'Alessandro, L. Weber and G. Burki
(Geneva Observatory) report:
We have carried out observations of the field of INTEGRAL GRB 030227
using the C2 CCD Camera (12'x 12') on the Swiss 1.2-meter telescope
at the ESO La Silla Observatory (Chile), beginning at 00:50 UT
on 2003 February 28. We obtained three images in the R band and one
in the V band each with an exposure time of 480 s.
The comparison between these images and the DSS does not allow us
to unambiguously detect the optical afterglow to GRB 030227 with
a V- and R-limit of 19.5 and 21 respectively.
In our images no object is present in the
XMM_Newton error circle (GCN #1901 and #1904).
This message may be cited.
GCN Circular 1904
Subject
GRB 030227, possible optical counterpart of XMM-Newton source
Date
2003-02-28T00:29:35Z (23 years ago)
From
Alberto Castro-Tirado at LAEFF-INTA <ajct@laeff.esa.es>
A.J. Castro-Tirado, D. Reverte, J. V�lchez (IAA-CSIC),
J. Gorosabel (IAA-CSIC/STScI), J. M. Castro Cer�n
(STScI), A. de Ugarte and S. Guziy (IAA-CSIC)
report:
"We have imaged a 30' x 30' region centred on the
INTEGRAL error box for GRB 020327 (Gotz et al. GCN
Circ. 1895, 1896) with the 2.5-m Isaac Newton
telescope at Observatorio del Roque de los Muchachos
(Canary Islands, Spain). One B-band frame and one
R-band frame (600-s exposure time each) were obtained
on Feb 27.872 UT (i.e. 12.2 hours after the GRB) under
good meteorological conditions. Within the X-ray source
error box given by XMM-Newton (Loiseau et al. GCN Circ.
1901) we find a point-like object (R = 22.5 preliminarly)
which is also marginally detected in the B-band frame.
Coordinates yield AR(2000) = 04 57 33.05, Dec(2000)
= +20 29 03.5 (preliminary, +/- 1"). Further observations
are needed to confirm whether this object is the optical
afterglow to GRB 030227. The object reported by Ofek and
Gal-Yam (GCN Circ. 1903) is also detected in our images
with R about 21.5. An image of the field is posted at:
www.iaa.csic.es/~ajct/GRBs/grb030227."
This message can be quoted.
GCN Circular 1903
Subject
GRB030227 - faint tentative OT candidate
Date
2003-02-27T22:44:49Z (23 years ago)
From
Eran Ofek at Tel Aviv U. <eran@wise1.tau.ac.il>
E.O. Ofek and A. Gal-Yam report:
We have observed the error circle of GRB030227 (GCN 1896)
with the Wise Observatory 1-m telescope.
We obtained 6x500 sec R-band images of the GRB position.
Comparing the combined images to the DSS2 R/I/B plates
we find a possible OT candidate.
However, the magnitude of the OT candidate is near
the limiting magnitude of both our images and the DSS plates.
We therefore consider the validity and variable nature of this
source to be uncertain at this stage.
The coordinates of the questionable OT are:
04:57:33.88 +20:29:43.3 (J2000.0)
Astrometry is based on 38 USNO-A2.0 stars with ~0.3" RMS.
The candidate approximate magnitude, based on ~40 USNO-A2.0 stars,
is R~21.3
Finding chart is available from:
ftp://wise3.tau.ac.il/pub/eran/GRB030227/
At 2003-02-27.7186 UT, the "OT" magnitude relative to the star designated "A"
in the finding chart (RA=04:57:33.81 Dec=+20:29:22.2, J2000) is: 3.74 mag.
An hour later (27.7610 UT), the OT candidate is not visible.
The OT is found 1.0"E and 21.1"N of reference star A.
We have also searched for an optical counterpart
at the position of the X-ray source reported in GCN 1901.
We detect no optical source to an approximate limiting magnitude of R~21.5
within the XMM error circle.
[GCN OPS NOTE (01mar03): The "Re:" and "(fwd)" were removed
from the Subject line.]
GCN Circular 1901
Subject
XMM-Newton observation of GRB030227
Date
2003-02-27T20:24:44Z (23 years ago)
From
Norbert Schartel at XMM-Newton/ESA <too@xmm.vilspa.esa.es>
N. Loiseau, M.Gilomo, R.Gonzalez-Riestra, M. Guainazzi, B. Juarez,
R. Perez-Martinez, P. Rodriguez, M. Santos-LLeo, and N. Schartel report:
Quick-Look-Analysis of the XMM-Newton observation
of GRB030227 (G. Gotz et al. GCN 1895 and 1896), based on
1 and 2 ks non-simultaneous exposures in the EPIC MOS and pn
cameras, respectively, shows the presence of one source in the
refined IBIS error circle:
S1 (J2000): R.A. = 4h 57m 33s Decl. = 20deg 29' 9"
with an estimated EPIC/pn count rate of 0.2 [counts/sec];
A second source, only marginally consistent with the error box
reported in GCN1896, is detected in the MOS cameras:
S2 (J2000): R.A. = 4h 57m 17s Decl. = 20deg 30' 18"
At this stage of reduction the positional error is expected to
be less than 6".
GCN Circular 1900
Subject
GRB030227: Kiso optical observations
Date
2003-02-27T17:19:43Z (23 years ago)
From
Yuji Urata at RIKEN <urata@crab.riken.go.jp>
H. Izumiura (OAO)
T. Aoki, Y. Urata on behalf of the KISO GRB Team report:
"We have observed the entire error circle of GRB030227 (Gotz et
al. GCN1895, 1896) with Kiso 1.05 Schmidt telescope starting at Feb
27. 10:43 UT (2.1 h after the burst). Multi band images were taken
with 2k x 2k CCD camera (50' x 50' field of view).
Our data;
Date Time (UT) Exposure Limiting mag.(R, SN=3)
02-27 10:43-10:48 300sec 20.3
02-27 12:44-12:54 600sec 20.9
From a comparison with the DSS-2 images we did not identify any new
point source for the GRB down to the limiting magnitude. Limiting
magnitudes were estimated by comparison with USNO-A2.0 red magnitudes
of many field stars. We also could not identify any variable objects
in the region using a PSF matched image subtraction method.
In our first frame, a minor planets Busch was located in the error
circle."
This message may be cited.
GCN Circular 1899
Subject
GRB 030227: Kyoto optical observation
Date
2003-02-27T15:57:58Z (23 years ago)
From
Hitoshi Yamaoka at Kyushu U., VSNET-GRB collab. <yamaoka@rc.kyushu-u.ac.jp>
M. Uemura, R. Ishioka, T. Kato (Kyoto U.) and H. Yamaoka (Kyushu U.)
report on behalf of VSNET-GRB collaboration:
We are observing the position of GRB 030227 (GCN 1895) starting at
Feb. 27 09:48 UT (1.1 hours after burst) with the 0.25-m telescope
(+unfiltered CCD) at Kyoto University. The stacked image (30 x 30s,
up to 10:19 UT) covers the entire refined error circle (GCN 1896),
assuming that the position figures in GCN 1896 was based on the
current equinox (see Note). Visual comparison of the stacked image to
the DSS 2 red image shows no new object down to a limiting magnitude
of about 18.0 (estimated with USNO-A2.0 red magnitudes of many field
stars). Further observation (also with the 0.30-m telescope) and
analysis is underway.
This message can be cited.
Note: The preliminary position given in GCN 1895 (04:57:29,
+20:29:23, the authors say it is based on J2000.0) coincided with the
position given in the GCN/INTEGRAL NOTICE at 09:29:48 UT (hereafter
GIN) based on the current equinox. If the position in GCN 1896 is
truely based on the equinox J2000.0, the refined error circle
intersects the initial error circle reported in GIN, and our stacked
image covers about 70 percent of the refined error circle. Our field
of view covers about 80 percent of the initial error circle reported
in GIN.
GCN Circular 1896
Subject
GRB030227: refined INTEGRAL position
Date
2003-02-27T12:29:15Z (23 years ago)
From
INTEGRAL Shift Ops at INTEGRAL <shift@isdcmail.unige.ch>
D.Gotz, S.Mereghetti and J.Borkowski for the IBAS localization team
report:
Further analysis of GRB030227 leads to the following position:
RA: 04h 57m 32.23s DEC: +20deg 29' 54.4'' (J2000)
with an uncertainty of 3 arcmin radius.
The preliminary peak flux over 2 seconds is about 6x10e-8 erg/cm2/sec
in the 25-100 keV energy range .
This message may be cited.
GCN Circular 1895
Subject
GRB030227 localized by INTEGRAL
Date
2003-02-27T09:42:44Z (23 years ago)
From
INTEGRAL Shift Ops at INTEGRAL <shift@isdcmail.unige.ch>
D.Gotz, J. Borkowski, S.Mereghetti on behalf of the IBAS Localization
Team, the INTEGRAL Science Data Center and the INTEGRAL
Science Working team report the detection of GRB030227 at UTC 08:42 in
the field of view of the IBIS telescope.
The burst lasted about 20 seconds.
The preliminary position is RA 04h 57m 29s DEC +20deg 29m 23s (J2000)
with an
uncertainty of 5' radius.
This message may be cited.