GRB 010214
GCN Circular 1059
Subject
GRB010214, optical observations
Date
2001-05-04T10:43:04Z (25 years ago)
From
Evert Rol at U.Amsterdam <evert@astro.uva.nl>
E. Rol, I. Salamanca, L. Kaper, P. Vreeswijk (University of
Amsterdam), N. Tanvir (University of Hertfordshire), report on behalf
of a larger collaboration:
In order to verify the possible counterpart to GRB010214 (Rol et al.,
GCN 955), we obtained another set of images with the Isaac Newton
Telescope on February 21, 2001. Examination and comparison of these
images with those obtained at the INT on February 17 shows no evidence
for a further fading of the possible counterpart, as already suggested
in other reports (Gorosabel et al., GCN 972; Klose et al., GCN 997;
Fynbo, private comm.). Instead, the source has the same magnitude as
measured in the images obtained at the William Herschel Telescope on
February 16, R = 22.9 (Rol et al, GCN 955). We therefore conclude that
the optical counterpart of GRB010214 has not been detected, with upper
limits R ~ 23.5, R ~ 24.2 and R ~ 23.8 on Feb. 15.26, Feb. 17.25 and
Feb. 22.22 respectively (using the calibration of Henden, GCN
988). Since the decrease in intensity on Feb. 17 does not appear to be
an artifact in the images, the detected source likely is a variable
star.
This message can be cited.
GCN Circular 997
Subject
GRB 010214, I-band data
Date
2001-02-28T16:50:52Z (25 years ago)
From
Sylvio Klose at TLS Tautenburg <klose@tls-tautenburg.de>
S. Klose, B. Stecklum, H. Linz, and U. Laux (Thueringer Landessternwarte
Tautenburg)
report:
The error box of GRB 010214 (Gandolfi et al., GCN #932) was imaged
in the I-band using the Tautenburg Schmidt telescope equipped with
the Schmidt focus CCD camera (2k x 2k). The observing log is as follows:
Run 1: Feb 15, 0:55 UT - 1:35 UT and 2:24 UT - 3:05 UT
Run 2: Feb 16, 2:01 UT - 2:48 UT and 3:38 UT - 3:48 UT
Run 3: Feb 27, 3:44 UT - 4:24 UT.
The R-band afterglow candidate reported by Rol et al. (GCN #955) is
clearly detected on the combined frames taken during the second
observing run. Based on the DSS2 red coordinate system we obtain for this
source RA, DEC (2000) = 17:41:03.0, 48:34:29 (+/- 0.4"). Using the
photometric standards provided by Henden (GCN #988) we measure a mean
I-band magnitude of 21.9 +/- 0.4 during run 2.
The combined frames of run 1 are somewhat less deep and the same holds for
the combined frames of run 3. The source is also detectable on these
images but very close to the detection limit which excludes an aperture
photometry. However, a visual comparison of the optical appearance of the
afterglow candidate on these images with the optical appearance of a
near-by, faint stellar object at RA, DEC (2000) = 17:41:07.7, 48:35:02
(+/- 0.8") allows us to state that we see no evidence for a fading of the
afterglow candidate between run 1 and run 3. Any fading must be less than
about 0.5 mag.
In conclusion, if this source is the combined OT + underlying host
galaxy then even during our first observing run (about 0.7 days after the
burst) the I-band flux of the afterglow did not exceed the I-band flux of
the underlying host by more than about 50 percent.
The I-band image is posted on the Tautenburg Web page at
http://www.tls-tautenburg.de/research/grb010214.html. It can also be
obtained via anonymous ftp from ftp.tls-tautenburg.de, directory
/pub/klose/GCN/.
This message is quotable.
GCN Circular 988
Subject
GRB010214, field photometry
Date
2001-02-25T01:14:33Z (25 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 preliminary BVRcIc all-sky photometry for
the field of GRB010214 with the USNOFS 1.0-m telescope on one
photometric night with poor seeing. This 11x11arcmin field includes
the proposed counterpart and extends to approximately V=20.
All stars brighter than V=14 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/grb010214.dat
The current photometry has a potential external zero-point
error of about two percent that needs to be added in
quadrature to the Poisson errors given in the datafile.
The astrometry in this file is based on linear
plate solutions with respect to USNO-A2.0. The internal errors
are less than 100mas.
At least two additional nights of photometry will be added to the data
file when weather conditions permit.
GCN Circular 978
Subject
GRB010214 follow-up from Hanle
Date
2001-02-23T11:34:00Z (25 years ago)
From
SG Bhargavi at Indian Inst of Astrophysics <bhargavi@iiap.ernet.in>
On behalf of the GRB follow-up team at Indian Institute
of Astrophysics, Bangalore India , Ramanath Cowsik reports:
The field of GRB 010214 centered at BeppoSAX WFC error circle (GCN-933)
was imaged using the new 2.01m telescope at Indian Astronomical Observatory
(IAO), Mt. Saraswati, Hanle, India.
Two exposures of 600s each in B and R band were taken on 15th and 16th Feb,
2001. No flaring or fading sources have been detected w.r.t DSS2 image
down to the limit R > 22.0; we do see many objects below DSS limit, but
these have not varied >0.1 m between 2 epochs of our observations.
The J-band source reported by Di poala et al.(GCN-939) is detected
at R=22.2 +/- 0.22 on Feb 15.99 UT and is found to be constant in
brightness within the photometric error and
consistent with the measurements of Gorosabel et al(GCN-949)
It is at B >23.0 in the combined image of 1200 s on Feb 16.99 UT.
The photomertic calibration is done with respect to 12 of USNO-A2.0 stars
in this field.
The optical candidate reported by Jhu et al. (GCN-938) is not detected
in our images. The afterglow candidates reported by Rol et al. (GCN-955)
are not detected in our images , as they are below our detection limit.
GCN Circular 972
Subject
GRB 010214, Optical Observations
Date
2001-02-22T23:35:54Z (25 years ago)
From
Javier Gorosabel at LAEFF-INTA, Madrid <jgu@laeff.esa.es>
J. Gorosabel (DSRI, Copenhagen), J. P. U. Fynbo (ESO, Garching),
B. L. Jensen, H. Pedersen, J. Hjorth (U. of Copenhagen),
M. I. Andersen (University of Oulu),
K. Aksnes, T. Grav (University of Oslo), M. Holman (CFA, Harvard),
A. A. Kaas, T. Abbott (Nordic Optical Telescope), report
"We have examined the variable optical sources reported by Rol et al.
(GCN #955) in our NOT images taken on Feb 16.24 UT (GCN #949). We report
the following preliminary magnitudes assuming R = 18.4 for the USNO-A2.0
catalog star U1350_09300715 (GCN #955).
Date(UT) Filter Magnitude
===========================================
Object 1 Feb 16.24 R 22.88 +-0.22
Object 2 Feb 16.24 R 23.01 +-0.22
These values are consistent with the magnitudes found on Feb 15.26 (GCN #955)."
GCN Circular 955
Subject
GRB010214, candidate optical afterglow
Date
2001-02-21T17:41:23Z (25 years ago)
From
Evert Rol at U.Amsterdam <evert@astro.uva.nl>
E. Rol, I. Salamanca, L. Kaper, P. Vreeswijk (University of
Amsterdam), P. Lacerda (Leiden Observatory), S. Hodgkin, P.
Tzanavaris (University of Cambridge), N. Tanvir (University of
Hertfordshire), report on behalf of a larger collaboration:
"We have observed the BeppoSAX error box of GRB010214 (Gandolfi, GCN
#932) with the 4.2m William Herschel Telescope (+ Prime Focus) and
with the 2.2m Isaac Newton Telescope (+ WFC) at La Palma, as follows:
Telescope Date Filter Exp.time Seeing Lim. mag.
(UT) (secs) (") (3 sigma)
=================================================================
WHT (+PF) 2001 Feb 15.26 R 2 x 225 0.84 ~23.5
INT (+WFC) 2001 Feb 17.25 R 2 x 900 1.2 ~24.2
(Note that in our calibration, the USNO star mentioned by Masetti et
al. (GCN #945) has a magnitude of R=18.4 instead of R=18.3.)
Within the refined NFI error box (Frontera et al., GCN #950), we
detect one object which faded from R = 22.9 to R = 24.1 (1 sigma error
about 0.2 mag) between the two observations.
The source seems to be extended, likely to be due to an underlying
galaxy. We consider this object to be a strong candidate for the optical
afterglow of GRB010214. The candidate is located at RA = 17:41:02.9
and Dec = 48:34:30 (J2000; error about 1 arcsec).
Another variable source is located just outside the refined NFI error
box, though within the initial NFI error box (Gandolfi, GCN #937