GRB 011211
GCN Circular 1311
Subject
GRB011211: HST Observations of Optical Afterglow and Host Galaxy
Date
2002-03-28T06:32:29Z (24 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
D.W. Fox, J.S. Bloom, and S.R. Kulkarni (Caltech) report on behalf of
a larger collaboration:
"We have imaged the optical afterglow (GCN 1191) and presumed host
galaxy of GRB011211 (GCN 1215) with the Hubble Space Telescope and
STIS (Clear) instrument for 5133s on December 25.8 UT. The host
galaxy is clearly detected and extends for roughly 0.5 arcsec
northeast of the afterglow.
Our observations confirm the result of Burud et al. (GCN 1213), with
the caveat that the afterglow offset is approximately 0.3 arcsec and
to the southwest rather than the southeast of the host galaxy.
A GIF image of the near field may be found at:
http://www.astro.caltech.edu/~derekfox/grb011211/
GCN Circular 1303
Subject
GRB011211 revised BVRI field photometry
Date
2002-03-23T18:57:09Z (24 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 additional BVRcIc all-sky photometry for
an 11x11 arcmin field that is approximately centered on
the position of the optical transient for GRB011211 reported
by Grav et al. (GCN 1191) with the USNOFS 1.0-m telescope.
The field was observed on two more nights,
with the new dataset posted at:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb011211.dat
Stars brighter than V=13.5 are saturated and should be used with care.
The current photometry has a potential external zero-point
error of about one percent. The astrometry in this file
is based on linear plate solutions with respect to USNO-A2.0.
The internal errors are less than 100mas.
The two new nights have shown that the photometry
reported in GCN 1197 has larger error than originally estimated,
most likely caused by a combination of the very poor seeing,
high airmass and approaching dawn. For example, the
comparison star U0675_11427359 that was used by Grav et al.and
Jensen et al. (GCN 1195) to calibrate their field can be found
in the new .dat file with the following magnitudes:
GCN 1195 (Jensen) B = 18.65 V = 18.18 R = 17.90 I = 17.07
GCN 1197 (Henden) B = 18.65 V = 18.11 R = 17.76 I = 17.42
new result B = 18.48 V = 18.00 R = 17.70 I = 17.37
We apologize for the lateness of this correction, but this
winter has had unusually few photometric nights. This is
the first case in several dozen calibrations that we have
performed for the GRB community in which the final dataset
differed from the initial dataset by more than a couple of percent.
GCN Circular 1215
Subject
GRB011211: BeppoSAX/GRBM data
Date
2002-01-07T18:45:54Z (24 years ago)
From
Filippo Frontera at ITESRE CNR <filippo@tesre.bo.cnr.it>
F.Frontera, Physics Dept. University of Ferrara, Ferrara and Istituto
Astrofisica Spaziale and Fisica Cosmica (IASF), CNR, Bologna; L. Amati,
IASF, CNR, Bologna; C. Guidorzi and E. Montanari, Physics Dept,
University of Ferrara; E. Costa, M. Feroci, L. Piro, IASF, CNR, Rome; J.
Heise, Space Research Organization Netherlands (SRON), Utrecht; and J.J.M.
in 't Zand, Astronomical Institute and SRON, Utrecht, report:
With reference to the GRB011211(=XRF011211) (GCN 1188, 1189), a detailed
analysis of the BeppoSAX GRBM data shows a very shallow long event in the
40-700 keV band with two peaks and a total duration of about 270 s,
similar to that measured in X-rays (2-28 keV) with the BeppoSAX WFC. The
quick look analysis could not single out such long and faint signal. The
40--700 peak flux (with 8 s bins) is about 0.5 x10^-7~erg/cm^2 s, while
its fluence is about 5x10^-6 erg/cm^2. The X/gamma fluence ratio is
similar to that found in a number of ordinary GRBs detected by BeppoSAX.
The distinguishing features of GRB011211 are its long duration (the
longest event localized with BeppoSAX) and its faintness both in X- and
gamma-rays. We conclude that this event cannot be classified as an X--ray
flash. From the measured redshift (z = 2.14, Fruchter et al. GCN 1200),
the gamma ray energy released, assuming isotropy, is 6.3x10^52 erg,
assuming a Friedman-Robertson-Walker cosmology with H0=65 Km/s Mpc and
Omega_m=0.3.
This message can be cited.
GCN Circular 1214
Subject
Optical polarization observations for GRB011211
Date
2002-01-01T20:47:03Z (24 years ago)
From
Stefano Covino at Brera Astronomical Observatory <covino@merate.mi.astro.it>
S. Covino, G. Ghisellini, P. Saracco, G. Tagliaferri, F. Zerbi
(Observ. of Brera, Milan, Italy); S. Di Serego, A. Cimatti (Observ. of Arcetri,
Florence, Italy); F. Fiore, G.L. Israel, L. Stella (Observ. of Monte Porzio,
Rome, Italy); N. Kawai (RICHEN, Japan); D. Lazzati (IoA, Cambridge, UK); S.
Ortolani (University of Padua, Italy); L. Pasquini (ESO, Garching, Munich,
Germany); G. Ricker (MIT, USA); R. Gilmozzi, E. Pompei (ESO, Paranal, Chile)
report:
On 2001 December 13.29 we observed the optical counterpart to the X-ray
rich GRB011211 that was reported by Grav et al. (GCN 1191). The observations
were performed with the ESO VLT-3 (Melipal) telescope equipped with FORS1
with a Bessel R band filter in the imaging polarimetry mode. The transient
source is clearly detected and the acquisition image allowed to derive the
Bessel V magnitude of the transient, V=21.81 +/- 0.06, with respect to the
USNO star U0675_11427359 (Henden, GCN 1197).
Polarimetric measurements were performed by means of PSF fitting and
aperture techniques for the optical transient and a number of field stars in
order to estimate the average Galactic dust induced field polarization.
The result is that the optical transient polarization is consistent with zero
within the observational uncertainties. We estimate an upper limit to the
linear polarization of the OT of about 2.5%. Further analyses are in progress.
A plot in the Q and U Stokes' vector plane for the field objects is shown at
the URL: http://www.merate.mi.astro.it/~covino/GRB011211/GRB_POL.jpg. The OT
is in red.
This message is citeable.
GCN Circular 1213
Subject
GRB 011211: Detection of the Probable Host Galaxy
Date
2001-12-24T20:55:58Z (24 years ago)
From
Andrew S. Fruchter at STScI <fruchter@stsci.edu>
GRB011211: Detection of the Probable Host Galaxy
Ingunn Burud, James Rhoads, Andrew Fruchter (STScI) and
Jens Hjorth (Copenhagen) report on behalf of
GRACE (Gamma-Ray Afterglow Collaboration at Eso):
We have obtained a deep R-band image (1 hour integration) of
GRB011211 from the VLT+FORS2 on Dec. 21.79 in 0."65 seeing.
We find that the source at the position of the afterglow is now
an extended object. By deconvolving the image (using the technique
of Magain, Courbin & Sohy, 1998, ApJ, 494, 452) we find the OT
to be superposed on an apparent host galaxy. The OT is offset
from the center of the host by 0."5 to the southeast.
The total magnitude of the system is R = 24.2 +/- 0.2, with the
magnitude of the host estimated at R = 25.0 +/- 0.3 and that of the
OT R = 24.8 +/- 0.3.
The image may be found at:
http://www.stsci.edu/~burud/Web/GRB/grb011211.html
GCN Circular 1211
Subject
Color indices of the afterglow of GRB011211
Date
2001-12-21T16:15:29Z (24 years ago)
From
Graziella Pizzichini at TESRE/CNR <graziell@tonno.tesre.bo.cnr.it>
V. Simon, R. Hudec (Astronomical Institute AV CR, Ondrejov) and
G. Pizzichini, N. Masetti (ITESRE, Bologna) report:
We have determined the color indices of the optical afterglow of
GRB011211 from the available data (GCN 1199, GCN 1200, GCN 1209),
using the calibration by Henden et al. (GCN 1197). The interpolation
method described in Simon et al. (2001, A&A, 377, 450) was used. The
indices of the afterglow of GRB011211 are:
t-To=0.503 days: V-R=0.39; R-I=0.42
t-To=1.183 days: B-V=0.52; V-R=0.44; R-I=0.53
t-To=1.463 days: V-R=0.28; R-I=0.60
The typical error of these indices is about 0.10 - 0.15 mag.
The Galactic reddening E(B-V)=0.042, determined from the maps by
Schlegel et al. (1998, ApJ, 500, 525), is comparable to the
errors of the measurements and can be neglected here.
These indices are close to the mean values of a sample of 17
afterglows (Simon et al. 2001) which yield (B-V)o=0.47+/-0.17,
(V-R)o=0.40+/-0.13, (R-I)o=0.46+/-0.18. This suggests that the
shape of the spectrum of the afterglow of GRB011211 is very similar
to the other afterglows and that its intrinsic reddening (that is
inside the host galaxy) must be again quite small (Simon et al.
2001). The search for the host galaxy and the determination
of its type are therefore encouraged.
GCN Circular 1209
Subject
GRB 011211, spectrum and optical photometry
Date
2001-12-18T18:32:08Z (24 years ago)
From
Peter Garnavich at U of Notre Dame <pgarnavi@miranda.phys.nd.edu>
M. Gladders (OCIW), S. Holland, P. M. Garnavich (Notre Dame),
S. Jha, K. Z. Stanek, D. Bersier (CfA), L. F. Barrientos (U. Catolica)
Spectra of the candidate afterglow of GRB 011211 (Grav et al. GCN 1191)
were obtained with the Magellan 6.5m Walter Baade telescope and
LDSS-2 imaging spectrograph on 2001, Dec. 13.3 (UT). The spectra
cover the range 400 nm to 900 nm at a resolution of 1.2 nm (FWHM).
Four exposures, each with an exposure time of 620s, were fully reduced
and combined. The final spectrum shows a smooth continuum
except for a number of narrow absorption lines in the blue.
Observed ID z
-------- --------- ----
524.8 nm Al II (167.1) 2.141
486.5 C IV (154.9) 2.141
479.4 Si II (152.7) 2.140
439.3 Si IV (139.8) 2.142
409.1 O I/Si II (130.3) 2.140
A broad, unidentified feature is seen at 460.0 nm (146.5 nm rest frame).
These identifications confirm the redshift of z=2.14 found by
Fruchter et al. (GCN 1200).
R-band images were also obtained in imaging mode on
Dec. 12 and 13 (UT). Assuming R=17.76 U0675_11427359
given by Henden (2001, GCN 1197) we find the following
magnitudes for the probable afterglow:
Dec. 12.25 20.28 +/-0.02
Dec. 12.34 20.58 +/-0.02
Dec. 13.31 21.46 +/-0.04
which provide a power law index of 0.9, consistent with the
optical decline rates found by Soszynski et al. (GCN 1199) for
the same time interval.
The fits images and spectra are available at
http://www.astro.utoronto.ca/~gladders/GRB/
This message may be cited.
GCN Circular 1204
Subject
GRB 011211: Evidence for an Optical Break
Date
2001-12-14T22:09:28Z (24 years ago)
From
Stephen Holland at U. of Notre Dame <sholland@nd.edu>
GRB 011211: Evidence for an Optical Break
S. Holland (Notre Dame), P. Berlind, D. Bersier, S. Jha, K. Z. Stanek
(Harvard-Smithsonian Center for Astrophysics), I. Soszynski (Warsaw
University Observatory), P. M. Garnavich (Notre Dame) report:
We have obtained deep VRI images of the field containing GRB
011211 using the 1.2-meter telescope with the 4Shooter at the Fred
Lawrence Whipple Observatory on Dec. 14.5 UT. The optical afterglow
of GRB 011211 is not visible on any of our images. The predicted
magnitudes, based on the power-law fits of Soszynski et al. (2001, GCN
1199), and the estimated limiting magnitudes of our images are give
below.
Filter Predicted Limiting Magnitude
V 22.10 22.3 +/- 0.2
R 21.99 22.4 +/- 0.2
I 21.25 21.0 +/- 0.2
These magnitudes are relative to the VRI magnitudes for USNO star
U0675_11427359 given by Henden (2001, GCN 1197).
Our non-detection suggests that there has been a break in the
light curve of the optical afterglow of GRB 011211. The break
occurred between 1.5 and 2.7 days after the burst (between Dec. 13.3
and Dec. 14.5). The R-band limiting magnitude suggests that the slope
after the break is at least -1.4. The V- and I-band limiting
magnitudes are consistent with no break.
This message may be cited.
GCN Circular 1203
Subject
GRB 011211: TNG Spectroscopic Observations
Date
2001-12-14T18:45:21Z (24 years ago)
From
Angelo Antonelli at Obs. Astro. di Roma <angelo@coma.mporzio.astro.it>
F. Fiore, G.L. Israel, L.A. Antonelli, L. Stella (OA Roma), S. Covino,
P. Saracco, G. Ghisellini (OA Brera), A. Buzzoni, T. Oliva (TNG),
E. Pian (OA Trieste), E. Palazzi, N. Masetti (ITeSRe, CNR, Bologna)
on behalf of a larger collaboration, report:
"Spectra of the OT (Grav et al.: GCN #1191) of GRB011211 in the
350-750nm range (total exposure time of about 1hr) were obtained with
the 3.5m Telescopio Nazionale Galileo (TNG) equipped with DOLORES +
grism #1 on Dec. 13.27 (UT). The source was relatively faint, V~21.7,
and the signal to noise of our spectra does not allow the detection
of faint absorption lines. The continuum is peaked in the blue band,
and consistent with the V-R of 0.2 measured by Soszynski et al.
(GCN #1199