- GCN/INTEGRAL NOTICE
TITLE: GCN/INTEGRAL NOTICE
NOTICE_DATE: Wed 03 Dec 03 22:01:45 UT
NOTICE_TYPE: INTEGRAL Wakeup
TRIGGER_NUM: 1224, Sub_Num: 0
GRB_RA: 120.6154d {+08h 02m 28s} (J2000),
120.6500d {+08h 02m 36s} (current),
120.1748d {+08h 00m 42s} (1950)
GRB_DEC: -39.8444d {-39d 50' 39"} (J2000),
-39.8555d {-39d 51' 19"} (current),
-39.7035d {-39d 42' 12"} (1950)
GRB_ERROR: 2.72 [arcmin, radius, statistical only]
GRB_INTEN: 15.81 [sigma]
GRB_TIME: 79296.08 SOD {22:01:36.08} UT
GRB_DATE: 12976 TJD; 337 DOY; 03/12/03
SC_RA: 126.69 [deg] (J2000)
SC_DEC: -50.10 [deg] (J2000)
SUN_POSTN: 249.78d {+16h 39m 07s} -22.14d {-22d 08' 12"}
SUN_DIST: 101.96 [deg]
MOON_POSTN: 17.61d {+01h 10m 26s} +4.35d {+04d 20' 48"}
MOON_DIST: 102.79 [deg]
GAL_COORDS: 255.73, -4.80 [deg] galactic lon,lat of the burst
ECL_COORDS: 138.06,-58.28 [deg] ecliptic lon,lat of the burst
COMMENTS: INTEGRAL GRB Coordinates.
- GCN/INTEGRAL NOTICE
TITLE: GCN/INTEGRAL NOTICE
NOTICE_DATE: Wed 03 Dec 03 23:01:14 UT
NOTICE_TYPE: INTEGRAL Offline
TRIGGER_NUM: 1224, Sub_Num: 1
GRB_RA: 120.6262d {+08h 02m 30s} (J2000),
120.6608d {+08h 02m 39s} (current),
120.1856d {+08h 00m 45s} (1950)
GRB_DEC: -39.8470d {-39d 50' 48"} (J2000),
-39.8581d {-39d 51' 28"} (current),
-39.7061d {-39d 42' 21"} (1950)
GRB_ERROR: 2.50 [arcmin, radius, statistical only]
GRB_INTEN: 15.81 [sigma]
GRB_TIME: 79296.08 SOD {22:01:36.08} UT
GRB_DATE: 12976 TJD; 337 DOY; 03/12/03
SC_RA: 126.69 [deg] (J2000)
SC_DEC: -50.10 [deg] (J2000)
SUN_POSTN: 249.78d {+16h 39m 07s} -22.14d {-22d 08' 12"}
SUN_DIST: 101.95 [deg]
MOON_POSTN: 17.61d {+01h 10m 26s} +4.35d {+04d 20' 48"}
MOON_DIST: 102.79 [deg]
GAL_COORDS: 255.73, -4.80 [deg] galactic lon,lat of the burst
ECL_COORDS: 138.07,-58.28 [deg] ecliptic lon,lat of the burst
COMMENTS: INTEGRAL GRB Coordinates.
- GCN notice #2459
D. Gotz, S Mereghetti, M. Beck and J. Borkowski on behalf of the IBAS
Localization Team, N. Mowlavi on behalf of the INTEGRAL Science Data
Centre and the INTEGRAL Science Working Team report:
A 20 s long GRB has been detected with IBAS at 22:01:28 UTC.
The GRB has been detected in IBIS/ISGRI data in the 15-200 keV energy
band.
The coordinates (J2000) are R.A. 08h 02m 30s Dec. -39deg 50'' 49' with an
uncertainty of 2.5 arcmin.
This message can be cited
- GCN notice #2460
S. Mereghetti and D. Gotz on behalf of the IBAS Localization Team and the
INTEGRAL Science Working Team report:
Preliminary analysis of GRB 031203 gives a peak flux of about 1.2
photons/cm^2/s (1.3 x 10^-7 erg/cm^2/s) in the 20-200 keV range
(integration time of 1 s).
The burst consists of a single peak lasting about 30 s.
This message can be cited
- GCN notice #2462
Maria Santos-Lleo and Pedro Calderon on behalf of the XMM-Newton
Science Operations Center, report:
XMM-Newton will observe the GRB031203 field, centered at
location RA=+08h 02m 30s and DEC=-39d 50' 48" (J2000), from
GCN 2459.
The observation is planned to start at 03:52 UT,
on December 4, 2003, for an exposure of 59000 seconds.
- GCN notice #2463
GRB 031203: Optical/IR SMARTS Observations
C. Bailyn, M. Buxton, B. Cobb, P. van Dokkum (Yale), J. S. Bloom
(Harvard/CfA) and J. Espinoza (CTIO), part of the larger SMARTS
consortium, report:
"Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging at the location of the INTEGRAL
GRB 031203 (GCN #2459) starting at 4 December 2003 3h00m UT.
Comparison of optical images obtained between UT=3:00 and UT=5:37
revealed no variable object down to I=19 mag. J and K band images
were also obtained during this time, and show no anomalous objects
when compared to the 2MASS survey. Owing to the heavy extinction
towards this GRB---E(B-V) = 0.971 mag (Schlegel, Finkbeiner,
& Davis ApJ 500, 525 1998)---red and infrared imaging is particularly
encouraged."
For more information on the SMARTS consortium see:
http://www.astro.yale.edu/smarts/
This message may be cited.
- GCN notice #2464
M. Santos-Lleo and P. Calderon report:
Quick-Look-Analysis of the XMM-Newton observation of the
GRB031203 field (D. Gotz et al. GCN 2459), based on
4 ks and 6 ks exposures in the EPIC pn and MOS cameras,
respectively, shows the presence of two sources within the
INTEGRAL error circle, with the first one much closer
to the INTEGRAL position than the second.
S1 (J2000): R.A. = 8h 2m 30.3s Decl. = -39deg 51' 2.4"
with an estimated EPIC/pn count rate of 0.1 [counts/sec];
S2 (J2000): R.A. = 8h 2m 20.8s Decl. = -39deg 52' 16.2"
with an estimated EPIC/pn count rate of 0.04 [counts/sec]
At this stage of reduction the position error is expected to
be less than 6".
- GCN notice #2465
G.Bourban*, A.Bram**, G.Burki*, T.Courvoisier* and L.Weber* report:
(* Geneva Observatory, Switzerland)
(** Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Belgium)
We have carried out optical observations of the field of INTEGRAL GRB
031203 using the P7 photometer's guiding Camera (6.5'x 6') mounted on
the Belgian MERCATOR 1.2-meter telescope located at La Palma Observatory
(Canary Islands), beginning at 03:44 UT on 2003 December 04 (5.7 hours
after the burst). We obtained four unfiltered images, with exposure
times of 180 and 480 s.
The comparison with the USNO-A2 catalog of the 2.5' error circle around
the position provided by INTEGRAL (GCN #2459) as well as the 6" ones
around the two positions provided by XMM NEWTON (GCN #2464) does not
reveal any new source down to a limiting magnitude of V < 17.6.
This message may be cited.
- GCN notice #2466
GRB 031203: IR REM Observations
F.M.Zerbi, G.Chincarini, S. Covino, E. Molinari, A. Di Paola, D.
Fugazza, V. Testa,
M. Rodono', L.A. Antonelli, P. Conconi, G. Cutispoto, L. Nicastro, G.
Tosti,
L. Burderi, S. Campana, C. Campeggi, G. Crimi, R. Cunniffe, J. Danzinger,
A. Fernandez-Soto, F. Fiore, F. Frontera, G. Gentile, G. Ghisellini,
P. Goldoni, G. Israel, B. Jordan, D. Lazzati, D. Lorenzetti, D. Malesani,
E. Martinetti, N. Masetti, R. Mazzoleni, B. Mc Breen, A. Melandri, S.
Messina,
E. Meurs, A. Monfardini, G. Nucciarelli, M. Orlandini, J. Paul, E.
Palazzi, E. Pian,
P. Saracco, S. Sardone, A. Simoncelli, M. Stefanon, L. Stella, L.
Tagliaferri, M. Tavani, G. Tosti, S. Vergani, F. Vitali.
The REM telescope, currently in commissioning phase, observed the field
of the
INTEGRAL GRB 031203 starting at 4 December 04h15m UT in J, H and Ks filters.
Observation in the visible band with ROSS spectrograph were not possible at
this stage for technical reasons.
We found an object not present in the 2MASS catalog in the S1 XMM-Newton
error box (GCN #2464). This object is found in the H and Ks images
(approximate magnitudes H=14.9 +/- 0.2, Ks=13.4 +/- 0.2) and not in the
J image (J upper limit 16.5). Note that this object would
have been detected in the 2MASS H and K filters.
The transient is nearby (~5") to another weak object already
present in the 2MASS. The coordinates of the transient are (J2000):
R.A. = 08h 02m 29.7s Dec. = -39deg 51' 09.5". At this stage of
reduction the position error is expected to be of the order of 1".
This message may be cited.
- GCN notice #2467
Laura Tomas on behalf of the XMM-Newton Science
Operations Center, report:
XMM-Newton will serendipitously observe the sources
reported in GCN 2464 (M.Santos-Lleo and P.Calderon)
during an upcoming scheduled calibration observation
of Zeta Puppis. The sources are about 10 arcmin
off-axis and therefore well within the field of view.
The observation is planned to start at 17:53 UT,
on December 6, 2003, for an exposure time of
62000 seconds.
- GCN notice #2468
GRB 031203: Apparent Spectral Break
C. Bailyn, P. van Dokkum, B. Cobb, M. Buxton (Yale) and J. S. Bloom
(Harvard/CfA) report further analysis of SMARTS data (see GCN #2463)
obtained between December 4 UT=3:00 and UT=6:11:
"The summed images reveal no source in I or J at the REM position (GCN
2466). The I-band upper limit is I=23 mag. In J, a faint source at
J=20.5 +/- 0.5 mag, undetectable in I, is found near the REM position at
RA = 8:02:29.78 dec = -39:51:07.1 (J2000)
+/- 0.4 arcseconds (1 sigma; found from astrometric tie to 2MASS)
No other source is found within 4.5" of the REM position. The J-band
data were obtained starting at UT=4:19, and are thus essentially
contemporaneous with the REM observations, while the I-band images span
the whole three hours of observations. There are a number of sources
with I<22 within the XMM-Newton error circles (GCN #2464), but none of
them vary by more than 0.1 magnitudes over the three hour time series.
If the REM source and the faint J source are in fact the same, J-K = 7
mag, whereas H-K = 1.5 mag. If the faint J source is not the
counterpart of the REM source, then J-K > 7. This extreme color
requires either very unusual extinction, a very unusual spectral
energy distribution, or rapid time variability of many magnitudes
sampled differently by the SMARTS and REM observations. One
interpretation is that this source is a J-band dropout, located
at a redshift >~ 9."
A website with finding charts, spectral energy distributions, and
other information will soon be available at
http://www.astro.yale.edu/dokkum/GRB031203.html
This message may be cited.
- GCN notice #2469
Reichart, D. (U. North Carolina) comments:
Assuming that the new, bright source that Zerbi et al. (GCN 2466) have
identified in H and Ks in the very small (<6") S1 XMM-Newton error circle
(Santos-Lleo & Calderon, GCN 2464) is indeed the afterglow of GRB 031203
(Gotz et al., GCN 2459), the deep limits that Bailyn et al. (GCN 2468)
measure at the location of this source in I and J do indeed imply a sharp
spectral break between the H and J bands: J - H > 5 mag and H - Ks ~ 1 mag
when corrected for Galactic extinction (Bailyn et al., GCN 2468).
Although one explanation for this dropout signature might be that GRB
031203 is at redshift z ~ 10, this is difficult to reconcile with the
brightness of the afterglow (Price, private communication), which is
probably in the top 10% of all afterglows.
Nor can so sharp a spectral break be explained by extinction by regular
dust, whether Galactic or in the source frame.
However, the dust along the line of sight, at least within hundreds of
parsecs of the GRB, should *not* be regular. Although dust within parsecs
to tens of parsecs of the GRB will be returned to the gas phase by
sublimation, dust at greater distances -- out to hundreds of parsecs --
will be repeatedly fragmented by grain charging and Coulomb explosions
(Waxman & Draine 2000, Fruchter, Krolik & Rhoads 2001, Reichart 2001).
If most of the dust fragments down to PAH sizes, its visual absorption edge
-- which can be quite sharp -- will shift to the source-frame R or I band
(the exact wavelength depends on the size of the grains; Li & Draine 2001).
Longer-wavelength light will pass through this dust as if were not even
there.
For a GRB at a typical redshift of z ~ 1, this visual absorption edge will
be redshifted to between the J and H bands. Such a redshift would also be
easier to reconcile with the brightness of the GRB 031203 afterglow in the
H and Ks bands.
So actually, every highly extinguished, low- to moderate-redshift GRB
afterglow might look like this in the NIR.
For GRB 031203, this hypothesis can be tested by (1) pursuing NIR
spectroscopy tonight while the afterglow is still sufficiently bright, but
be warned that if at z ~ 1 H-alpha might be blueward of the spectral break,
and/or (2) pursuing deep imaging blueward of the spectral break in hopes of
identifying a typical-redshift host galaxy, but again be warned: since the
Galactic A_V ~ 3 mag and possibly more along this line of sight, J, z, and
I bands are preferred.
The Follow-Up Network for Gamma-Ray Bursts (a.k.a. the FUN GRB
Collaboration), the resources of which are currently concentrated more in
the northern hemisphere, will not be able to pursue either of these
observing strategies tonight.
- GCN notice #2470
GRB031203 : Optical Observation of Lulin Observatory
C.H. Hsia, H.C. Lin (NCU)
K.Y. Huang, Y. Urata, W.H. Ip, T. Tamagawa on behalf of Lulin the GRB
team report:
"We observed the location of the INTEGRAL GRB031203(Gotz et al. GCN2459)
with 1.0m telescope at Lulin Observatory (Institute of Astronomy, National
Central University, Taiwan) from 5 December 2003 18.6 UT to 19.6 UT.
There are 6 images taken at I-band with exposure time 300 sec(1 frame)
and 600 sec(5 frames).
Comparison with DSS2 I-band image, a new source was found at RA= 08h
02m 30.1s Dec= -39deg 51' 03.3"(J2000) in our combined image. It is in
the error region of the S1 of XMM-Newton observation (M. Santos-Lleo
and P. Calderon, GCN2464). There are no new object was observed at S2.
Image with comparison DSS2 is posted at :
http://cosmic.riken.go.jp/urata/GRB/GRB031203/grb031203_chart.gif
Further analysis and observation are in progress."
This message may be cited
- GCN notice #2471
GRB 031203: IR NTT observations do not confirm REM detection
F.M. Zerbi, G. Chincarini, S. Covino, E. Molinari, A. Di Paola, D.
Fugazza,
V. Testa, M. Rodono', L.A. Antonelli, P. Conconi, G. Cutispoto,
L. Nicastro, G. Tosti, L. Burderi, S. Campana, C. Campeggi, G. Crimi,
R. Cunniffe, J. Danzinger, A. Fernandez-Soto, F. Fiore, F. Frontera,
G. Gentile, G. Ghisellini, P. Goldoni, G. Israel, B. Jordan, D. Lazzati,
D. Lorenzetti, D. Malesani, E. Martinetti, N. Masetti, R. Mazzoleni,
B. Mc Breen, A. Melandri, S. Messina, E. Meurs, A. Monfardini,
G. Nucciarelli, M. Orlandini, J. Paul, E. Palazzi, E. Pian,
P. Saracco, S. Sardone, A. Simoncelli, M. Stefanon, L. Stella,
L. Tagliaferri, M. Tavani, G. Tosti, S. Vergani, F. Vitali.
We observed in JHKs filters with SofI at the NTT telescope the field of the
INTEGRAL GRB 031203 (Gotz et al. GCN 2459) starting at 4 December 04h54m
UT. The object detected by the REM telescope in the H and Ks filters
(see Zerbi
et al. GCN 2466) was not detected in these images, with upper limits of
J=22.2,
H=21.1, Ks_1=20.9 and Ks_2=20.2 (we have two exposures in the Ks filter
separated
by about 2.5 hours).
A reanalysis of the REM data confirmed the presence of the object reported
in GCN 2466. We are still investigating the possible cause of it.
The object reported by Hsia et al. (GCN2470), associated with the XMM
source S1 (Santos-Lleo & Calderon GCN2464), is present in all SofI images,
with magnitudes J=18.2+/-0.08, H=17.35+/-0.04 and Ks_1=16.45+/-0.03
(exposure of 45 min starting at UT 04:54 and ending at UT 05:47)
and Ks_2=16.43+/-0.04 (exposure of 15 minutes starting at UT 07:30 and
ending at 07:46). Therefore, this object remained constant in the two Ks
images.
Last night we observed the field also with the VLT telescope and the
ISAAC camera. A report on the quick analysis of these data will be
given later today.
- GCN notice #2472
GRB 031203: Further reports on December 4 observations
J. S. Bloom (Harvard/CfA), C. Bailyn, and P. van Dokkum (Yale) report
on behalf of the larger SMARTS collaboration:
"The object inside the first XMM error circle (Santos-Lleo & Calderon,
GCN #2464) reported in Hsia et al. (GCN #2470) is unlikely to be
related to GRB 031203 (Gotz GCN #2459) by two accounts. First, as
reported in Bailyn et al. (GCN #2468), the source did not vary by more
than 0.1 magnitudes from about 4 to 7 hours after the GRB, as is the
case for all sources I<22 mag in the XMM error boxes. Second, the
source is present in the DSS-II scan of the F-plate image (dated 18
March 1991). We also clarify that both the REM and the ANDICAM
positions lie outside the nominal 6 arcsec error radius of the first
XMM source."
For finding charts, see
http://www-cfa.harvard.edu/~jbloom/grb031203
This message can be cited.
- GCN notice #2473
D. A. Frail (NRAO) reports on behalf of a larger collaboration:
"Using the Very Large Array at 8.5 GHz, we imaged a 2-arcminute radius
near the X-ray source S1, detected by the XMM (GCN#2464) within the
INTEGRAL error circle (GCN#2459). A single radio source is detected
close to the center of S1 at (J2000), r.a. = 08:02:30.22, dec. =
-39:51:02.8, with conservative errors of +/-0.4 arcsec. This source is
not detected in the NRAO VLA Sky Survey at 20-cm. The flux density of
this source is 0.5 mJy - typical for GRB afterglows. We caution that
the flux calibration at this stage is only preliminary.
The coincidences between the INTEGRAL position, and the position of
the XMM-S1 and VLA sources, argues for a real association. We will be
undertaking further observations to test whether the radio source is
the afterglow of GRB 031203."
- GCN notice #2474
P. Rodriguez-Pascual, M. Santos-Lleo, R. Gonzalez-Riestra,
N. Schartel, B. Altieri report:
Preliminary analysis of the XMM-Newton raw data of
the GRB031203 field (D. Gotz et al. GCN 2459), based
on the fully accumulated 56.3 ks exposure time in the
EPIC pn camera, confirms the two sources reported by
M. Santos-Lleo and P. Calderon (GCN 2464). The
observation was performed under optimal environmental
conditions and is basically free from solar background
flares.
XMMU J080230.3-395101, (S1 in GCN 2464) shows a decrease
of the pn count rate from approximately 0.075 counts/sec
(at start of observation) to approximately 0.05
counts/sec (at end of observation) within an extraction
radius of 30 arcsec.
There are very few counts in low-energy channels
(below approximately 0.9 keV) which may be explained
by the Galactic absorption.
XMMU J080220.8-395213 (S2 in GCN 2464) might also show
evidence for a decrease in flux, but the current
processing status of the data does not allow proper
quantification.
In addition to the two sources reported in GCN 2464
several weaker sources are visible in the data taken
during the 56.3 ks exposure time. The following sources
are located in the INTEGRAL error circle:
XMM-Newton Source counts distance in
to centre GCN
[1/sec] [arcsec] 2464
-----------------------------------------------------
XMMU J080230.3-395101 0.057+/-0.0012 13 S1
XMMU J080220.8-395213 0.018+/-0.001 135 S2
XMMU J080226.0-394955 0.003+/-0.001 69
XMMU J080230.7-395239 0.002+/-0.001 110
XMMU J080233.4-395150 0.003+/-0.001 73
XMMU J080238.2-395150 0.001+/-0.0007 112
XMMU J080239.4-395052 0.002+/-0.001 108
-----------------------------------------------------
The following sources fall on the border of the INTEGRAL
error circle:
XMM-Newton Source counts distance
to centre
[1/sec] [arcsec]
------------------------------------------------
XMMU J080234.3-394839 0.003+/-0.001 137
XMMU J080241.7-394944 0.002+/-0.001 149
------------------------------------------------
The following source falls just outside the INTEGRAL
error circle:
XMM-Newton Source counts distance
to centre
[1/sec] [arcsec]
------------------------------------------------
XMMU J080226.6-395334 0.003+/-0.001 170
------------------------------------------------
At this stage of the data processing the position error
for the weaker sources is of the order of 10 arcsec.
The XMM-Newton Science Operations Centre plans to
make preliminary images available on a dedicated web
page by the middle of next week.
- GCN notice #2475
J.X. Prochaska (UCO/Lick Observatory), H.W. Chen (MIT),
K. Hurley (UCB), J.S. Bloom (Harvard/CfA), J.R. Graham (UCB),
and W.D. Vacca (NASA/Ames) report:
Using SCAM with the NIRSPEC instrument on the KeckII telescope,
we imaged the ~50"x50" region surrounding GRB031203 (Gotz et al., GCN 2459).
We acquired exposures in the N3 (~J; 540s), N5 (~H; 360s), and
K' (540s) bands with approximately 0.5" seeing in photometric conditions.
Within the 6" XMM error circle, we identify 2 objects:
(1) A point source at RA=08:02:29 DEC=-39:51:09 (ANDICAM 1)
(2) A galaxy at RA=08:02:29 DEC=-39:51:12
The latter object nearly coincides with the VLA position of the radio
source in the XMM error box (Frail, priv. communication).
We believe the GRB event occurred within this galaxy.
The observed K'-band magnitude of the galaxy is 16.5 +/- 0.05
Adopting an extinction E(B-V)=0.97, we estimate a corrected
K'-band luminosity K'=16.15 mag. The galaxy also has an
ellipticity E=0.23 and PA=-8 deg.
Finally, adopting K'(M*) = -23.3 from the 2MASS survey (Bell et al. 2003),
we note an M* galaxy at z=0.17 would have K'=16.15 assuming an LCDM
cosmology and no evolution in the stellar population.
We also identify a ~5sigma object 1.4"N and 0.2E" of the galaxy center
with observed K' magnitude of 21.1 +/- 0.2. This tentative detection
lies within 0.5" of the VLA position.
No object was observed in our images at the position of
the REM source (Zerbi et al., GCN 2466) to K'<21.5 mag.
More details can be found here:
http://www.ucolick.org/~xavier/GRB/031203/index.html
This message may be cited.
- GCN notice #2476
GRB 031203: Deep NIR NTT & VLT observations
G. Tagliaferri, S. Covino, D. Fugazza, S. Campana, A. Simoncelli (INAF-OAB)
G. Chincarini (UNIMIB & INAF-OAB), L. Stella (INAF-OAR)
On December 5th, at 06:12 UT, we started observing in JHKs filters with
ISAAC
at the VLT-UT1 telescope the XMM source S1 (Santos-Lleo & Calderon
GCN2464).
In the XMM error box of 6" around S1 we detect the source already seen
in the
previous night with the NTT (Zerbi et al. GCN2471, see also Hsia et al.
GCN2470).
With ISAAC we obtained the following magnitudes (based on 2MASS stars):
J=18.40+/-0.15, H=17.80+/-0.15 and Ks=16.70+/-0.15. A comparison between the
NTT values on December 4 and the VLT one of the following night shows that
this object faded by few tens of magnitude. Given that this object was
already
detected in archive images (Bloom et al. GCN2472), it is probably a
variable star.
In the XMM error box with ISAAC we detect also another source with
J=21.05+/-0.25
(not visible in H and Ks). This object was already present in the SofI J
image and
it does not seem to have varied. We did not see any variable source in
an area of
20 arcsecond radius around the XMM S1 position. Therefore, we have no
indication of
a transient associated with GRB 031203. However, note that the VLT
images do not cover
the full INTEGRAL error box, in particular the area around the XMM S2
source is not in the FoV.
For the NTT SofI Ks finding charts, see
http://www.merate.mi.astro.it/~taglia/GRB031203.jpg
We thank the ESO La Silla and Paranal staff for their prompt reaction
and support.
This message can be cited.
- GCN notice #2477 (same as 2474)
XMM-Newton Observation of GRB031203
P. Rodriguez-Pascual, M. Santos-Lleo, R. Gonzalez-Riestra,
N. Schartel, B. Altieri report:
Preliminary analysis of the XMM-Newton raw data of
the GRB031203 field (D. Gotz et al. GCN 2459), based
on the fully accumulated 56.3 ks exposure time in the
EPIC pn camera, confirms the two sources reported by
M. Santos-Lleo and P. Calderon (GCN 2464). The
observation was performed under optimal environmental
conditions and is basically free from solar background
flares.
XMMU J080230.3-395101, (S1 in GCN 2464) shows a decrease
of the pn count rate from approximately 0.075 counts/sec
(at start of observation) to approximately 0.05
counts/sec (at end of observation) within an extraction
radius of 30 arcsec.
There are very few counts in low-energy channels
(below approximately 0.9 keV) which may be explained
by the Galactic absorption.
XMMU J080220.8-395213 (S2 in GCN 2464) might also show
evidence for a decrease in flux, but the current
processing status of the data does not allow proper
quantification.
In addition to the two sources reported in GCN 2464
several weaker sources are visible in the data taken
during the 56.3 ks exposure time. The following sources
are located in the INTEGRAL error circle:
XMM-Newton Source counts distance in
to centre GCN
[1/sec] [arcsec] 2464
-----------------------------------------------------
XMMU J080230.3-395101 0.057+/-0.0012 13 S1
XMMU J080220.8-395213 0.018+/-0.001 135 S2
XMMU J080226.0-394955 0.003+/-0.001 69
XMMU J080230.7-395239 0.002+/-0.001 110
XMMU J080233.4-395150 0.003+/-0.001 73
XMMU J080238.2-395150 0.001+/-0.0007 112
XMMU J080239.4-395052 0.002+/-0.001 108
-----------------------------------------------------
The following sources fall on the border of the INTEGRAL
error circle:
XMM-Newton Source counts distance
to centre
[1/sec] [arcsec]
------------------------------------------------
XMMU J080234.3-394839 0.003+/-0.001 137
XMMU J080241.7-394944 0.002+/-0.001 149
------------------------------------------------
The following source falls just outside the INTEGRAL
error circle:
XMM-Newton Source counts distance
to centre
[1/sec] [arcsec]
------------------------------------------------
XMMU J080226.6-395334 0.003+/-0.001 170
------------------------------------------------
At this stage of the data processing the position error
for the weaker sources is of the order of 10 arcsec.
The XMM-Newton Science Operations Centre plans to
make preliminary images available on a dedicated web
page by the middle of next week.
- GCN notice #2478
GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
S. Campana, G. Tagliaferri, G. Chincarini, S. Covino,
D. Fugazza (INAF-OAB), L. Stella (INAF-OAR)
We analysed ROSAT PSPC archival data of Zeta Puppis
(rp200663n00, on-time 55 ks).
The two XMM-Newton sources (Santos-Lleo & Calderon
GCN #2464) found in the INTEGRAL error box of GRB 031203
are within the inner rib of the PSPC.
ROSAT did not detect the two sources.
Using XIMAGE/sosta (and correcting for the exposure map),
we obtained a 3 sigma upper limit of
1.3E-03 c/s on S1 and of
1.1E-03 c/s on S2.
The column density of this field is 6x1021 cm-2.
Assuming a power law spectrum with photon index between
1-2, we can extrapolate (using PIMMS) XMM-Newton rates of
1.9E-02 - 3.5E-02 c/s for S1 and
1.5E-02 - 2.9E-02 c/s for S2.
The XMM-Newton sources have been estimated to have a rate of:
S1 0.10+/-0.015 c/s (error at 3 sigma)
S2 0.04+/-0.010 c/s (error at 3 sigma).
If our assumptions on the spectrum are correct,
we note that the XMM-Newton count rate of S1 is
not compatible with the ROSAT PSPC upper limit,
suggesting that S1 is an X-ray variable source.
- GCN notice #2479
J.X. Prochaska (UCO/Lick Observatory), H.W. Chen (MIT),
K. Hurley (UCB), J.S. Bloom (Harvard/CfA), J.R. Graham (UCB),
and W.D. Vacca (NASA/Ames) report:
The coordinates of the galaxy in GCN 2475 were given incorrectly.
The correct coordinates are:
RA = 08:02:30.18, Decl. = -39:51:03.5
We regret any confusion that this error might have caused.
- GCN notice #2481
GRB 031203: Optical/IR Astrometry
J. S. Bloom, C. Bailyn, M. Buxton, B. Cobb, P. van Dokkum (Yale) and
D. Gonzalez (CTIO),
part of the larger SMARTS consortium, report:
"The position of the radio source in the XMM error box (Frail, priv.
communication) is 0.43" E and 0.80" N from the bright source noted in Hsia
et al. (GCN #2470). However, as explained in Bloom et al. (GCN #2472) that
source itself is unlikely to be the afterglow since it was present in the
DSS-II and did not vary significantly in the first night.
Additional data obtained between Dec. 5 UT=5:43 and UT=7:19 showed the
source at the same I-band flux as on Dec. 4 to within 0.05 mag. On both
Dec. 4 and Dec. 5 the source is slightly but clearly elongated in ~1"
seeing.
The source-radio offset of 0.91" is larger than the formal joint
1 sigma uncertainty between the IR and the radio positional tie.
It is still unclear whether this bright source is the low redshift
host of the GRB or a foreground galaxy.
Separately, we note that inspection of the J-band ANDICAM imaging
reported in the Bailyn et al. (GCN #2463) reveals a faint (J ~ 20)
source at:
RA: 08:02:30.36 DEC: -39:51:00.1 (J2000)
rms uncertainty relative to ICRF= 0.3 arcsec in RA and DEC"
This is consistent with the XMM (#1) position. A finding chart may
be found at:
http://www-cfa.harvard.edu/~jbloom/grb031203
This message may be cited.
- GCN notice #2482
GRB 031203: Magellan spectrum of possible GRB host
J. X. Prochaska (UCO/Lick Observatory), J. S. Bloom (Harvard/CfA), H.W.
Chen (MIT), K. Hurley (UCB), A. Dressler (OCIW) and D. Osip (LCO)
report:
"Using the recently commissioned IMACS on the Baade telescope we obtained
a 300l grating spectrum of the galaxy laying within 1" of the VLA position
(Frail, priv. comm.) of the radio source in the XMM error circle
(Santos-Lleo & Calderon #GCN 2464) of the INTEGRAL-discovered GRB 031203
(Gotz et al. GCN #2459).
The spectrum covers 4100-9100 Ang and shows strong, extended emission
lines including Hbeta, [OIII], Halpha, [SII]. All of these lines are
consistent with a redshift z=0.105 (uncorrected for heliocentric motion)."
Data products will be released at as they become available.
http://www.ucolick.org/~xavier/GRB/031203/index.html
This message may be cited.
- Documentation on proper time-order of recent GCN Circulars
The table below shows the times when the Circulars were originally sent to GCN.
The proper assignment of priority can be determined from this table.
The circulars processing demon has been modified to prevent this type
of problem from occurring again. This is the 3rd time the demon has been
changed
to protect against an infinite loop. The Internet is a dynamic system
and once in a while I get behind the curve in matching GCN to the Net.
Which is to say that while I make strong efforts to prevent problems,
there are some times when I am re-active instead of pro-active.
I apologize for the inconvenience and loss of timely knowledge to the
community.
Sincerely,
Scott Barthelmy (GCN OPS)
TABLE OF CIRCULAR TIMES DURING THE INFINITE-LOOP PROBLEM
SendTime DistributeTime Delay Circ# Submiter Title
Dec05 06:06 Dec05 06:06 0 2469 D.Reichart GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
Dec05 06:10
Dec05 06:16 Dec06 14:32 31.7 2477 N.Schartel XMM-Newton Observation of GRB031203
Dec05 06:33 Dec06 13:44 31.1 2474 N.Schartel XMM-Newton Observation of GRB031203
Dec05 07:00 Dec06 14:48 31.1 2478 G.Tagliaferri GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
Dec05 08:24 Dec05 08:24 0 2470 K.Huang GRB031203 : Optical Observation of Lulin Observatory
Dec05 08:27 Dec06 14:16 29.7 2476 G.Tagliaferri GRB 031203: Deep NIR NTT & VLT observations
Dec05 12:39 Dec05 12:39 0 2471 G.Taliaferri GRB 031203: IR NTTobservations do not confirm REM detection
Dec05 13:11 Dec06 13:38 24.3 2473 D.Frail GRB 031203: Radio detection
Dec05 14:40 Dec05 14:40 0 2472 J.Bloom GRB 031203: Further reports on December 4 observations
Dec05 17:10 Dec06 14:00 20.9 2475 K.Hurley GRB031203: K' Photometry of the likely GRB host
Dec06 04:45 Dec06 17:25 12.7 2481 J.Bloom Optical/IR Astrometry
Dec06 11:29 Dec06 17:45 6.3 2482 J.Bloom Magellan spectrum of possible GRB host
Dec06 13:40
Dec06 16:18 Dec06 16:18 0 2479 K.Hurley RB031203 K prime photometry: correction to galaxy coordinates
Notes:
1) All dates and times are UT.
2) The "TimeSent" would normally be the "TimeReceived" (to within a minute),
but because of the full email in-coming queue, these submissions by the authors
were bounced. It is only after (a) the queue was cleared (at Dec06 13:40),
and (b) the sendmail demon on the sender's machine next tried to re-send
(in its standard periodic retrying) that the submission was received and
processes by GCN.
3) The "Delay" column is in hours.
4) Since these Circulars were delayed and distributed out of order, there are
undoubtedly cases of missing references to other Circulars. Please do not
blame the authors; the fault lies with GCN and Scott Barthelmy.
5) The only explanation as to why Circ's 2470-2472 worked properly (ie 0 delay)
that I can think of is that other activity with the mail queue momentarily
freed up some space which allowed them to go through.
- GCN notice #2483
A. M. Soderberg, S. R. Kulkarni (Caltech) and D. A. Frail (NRAO) report
on behalf of a larger collaboration:
"On 2004 Dec. 7.52 UT we carried out further VLA observations at
8.5 GHz of the radio source reported earlier (GCN 2473) and which
lies within the 6-arcsecond error circle of the XMM source S1 (GCN
2464). The source flux density has decreased by a factor of two
since our last report. Given that S1 is also fading (GCN 2477) we
conclude that likely the radio source is the afterglow of GRB
0312103 (GCN 2459).
As noted by Bloom et al. (GCN 2481) and Prochaska et al. (GCN
2482) a galaxy at a redshift of 0.105 is coincident with the radio
source. Owing to the large zenith angle of the source the reported
radio source position may suffer from larger than normal astrometric
error (which will be improved by future observations). The radio
source and the putative host galaxy can be considered to coincident
within the true astrometric error.
The isotropic energy release (assuming redshift of 0.105) in the
20-200 keV band is about 9E49 erg (using the data from GCN 2460). The
isotropic X-ray luminosity extrapolated to 10 hr (using data from
GCN 2477) is about 5E43 erg/s. These are lower than normal releases
and luminosities (see Berger, Kulkarni and Frail 2003) and the
apparent early fading in the radio are consistent with GRB 031203
being an abnormally low luminosity GRB. This GRB may bridge GRB
980425 (at z=0.0085) associated with SN 1998bw and cosmological
GRBs (typically z of 0.3 to 1). Further low frequency observations
will settle the issue of total calorimetry. The search for an
underlying SN is worth trying, though obscuration within and outside
our Galaxy may prove to be vexing."
- GCN notice #2484
Preliminary images from both XMM-Newton observations
of the field of GRB031203 are available at the
home-page of the XMM-Newton Science Operations Centre:
http://xmm.vilspa.esa.es/external/xmm_news/items/grb031203/index.shtml
- GCN notice #2485
In the "standard" fireball model, ordinary GRBs, XRFs and
low-inferred-luminosity GRBs, such as GRB 980425 are intrinsically
different. The low-luminosity GRB 031203 (GCN 2460, 2482) has thus
been interpreted as a case that "may bridge GRB 980425 ... and
cosmological GRBs" (GCN 2483).
In the cannonball model, XRFs and GRBs such as 980425 and 031203
(GCN 2460) are ordinary GRBs, also viewed off-axis but from angles
a few times larger than those of ordinary GRBs (astro-ph/0308248).
GRB 031203 offers sensitive observational tests of this CB-model
unification of XRFs and ALL long-duration GRBs:
In the CB-model --and in reality-- both for long GRBs and XRFs, the
product of the peak energy Ep (E at max E^2 dn/dE) and the full
width at half maximum (FWHM) of the photon flux in a single pulse is
approximately 200 keV s, independent of redshift.
From the reported 30 s total duration of the single-pulse GRB 031203
(GCN 2460) and from the fairly universal "FRED" temporal shape of
GRB pulses, we estimate the FWHM to be ~ 10 s. Consequently,
we predict Ep ~ 20 keV. Moreover, from the mean FWHM = 0.92 s of
long-duration GRB pulses, from their mean redshift z ~ 1, and from
the estimated z ~ 0.105 (GCN 2482) of GRB 031203, we conclude that
the value of the Doppler factor of its single pulse was approximately
20 times smaller than the mean value for long GRBs. In the CB model
this implies (astro-ph/0308248, astro-ph/0309294) a viewing angle
approximately 4 times larger than the average for the bulk of the GRB
sample. The predicted equivalent isotropic energy of GRB 031203
should then be ~ 2.5E49 erg. For a Hubble constant of 70 km/[s Mpc],
and a FWHM of ~ 10 s, this energy is indeed consistent with that
estimated from the reported peak energy flux of 1.3E-7 erg/[cm^2 s]
in the 20-200 keV interval (GCN 2460).
Due to a large Galactic extinction (E(B-V)=0.971; GCN 2463) in the
direction of GRB 031203, a standard-candle supernova akin to
SN1998bw placed at the GRB position will reach (around December 20)
a peak brightness R ~ 22 in the R band, if the extinction in the host
galaxy is negligible.
The radio afterglow may first decline for a couple of days (GCN 2483) and
then rebrighten, before declining again like t^{-1.33} at later times;
further steepening to the universal ~ t^{-2.1} as each specific radio
frequency crosses the CB-model's "injection bend" (astro-ph/0204474).
- Arnon Dar, Shlomo Dado and Alvaro De Rujula
- GCN notice #2486
C. Bailyn, P. van Dokkum, M. Buxton, B. Cobb (Yale) and
J. S. Bloom (Harvard/CfA) report continued monitoring
of the galaxy near the position of GRB 031203 (GCN 2482)
with the SMARTS 1.3m telescope + ANDICAM instrument at
CTIO:
"We have continued SMARTS/ANDICAM observations of the galaxy
coincident with the radio position (GCN 2473) of GRB 031203.
We are obtaining 42m of exposure time in I and J each night.
Our recent I-band data suggest that the galaxy has brightened
by 0.09 +/- 0.03 magnitudes over the past 2 nights, reaching I=19.13
in observations beginning Dec. 11 UT=5:27 (in addition to the
error in the differential magnitude, there is also an uncertainty
of ~0.05 in the absolute magnitude scale). This brightening may
mark the emergence of an underlying supernova, so we urge continued
observation of this source in all wavelengths."
- GCN notice #2489
S. Vaughan, R. Willingale, P.T. O'Brien, J. Osborne, A. Levan, J.
Tedds, T. Roberts, M. Watson (University of Leicester), D. Watson
(University of Copenhagen) report:
The first XMM-Newton observation of GRB031203 began at 2003-12-04, UT
04:09:29 and lasted for 58211 seconds (GCN2462). The GRB was
originally detected by the IBIS instrument on Integral at 2003-12-03,
UT 22:01:28 (GCN2459).
Analysis of the first XMM-Newton observation reveals a diffuse X-ray
halo centered around the GRB afterglow location. This halo is seen in
all three cameras of the EPIC instrument and is not due to scattered
optical or X-ray light within the instrument. The halo has the form of
a virtually complete ring which increases in radius through the
observation, indicative of the expected behaviour of a "light-echo" as
X-rays are scattered off dust at a distance of ~700 pc from the
observer.
GRB031203 is in the direction (Galactic) l = 255.74, b = -4.80
degrees, a line of sight which includes the Gum Nebula among other
nebulae and infrared sources. The derived distance to the scattering
medium is consistent with an origin in our Galaxy.
The X-ray spectrum of GRB031203 can be well represented by a powerlaw
with Photon index ~ 1.7. The scattered X-ray light has, as expected, a
softer spectrum with Photon index ~ 3.
Further analysis is underway.
- GCN notice #2490
J. A. Tedds (University of Leicester), D. Watson (University of
Copenhagen), M. G. Watson, J. Osborne, A. Levan, P.T. O'Brien, S. Vaughan,
R. Willingale (University of Leicester) and J. N. Reeves (NASA-GSFC)
report:
The XMM-Newton EPIC coordinates were refined by matching the X-ray sources
in the field to the USNO-A2 catalogue. The cross-correlation is extremely
good thanks to the long, clean exposure and yields a final source position
(J2000) for the X-ray afterglow (the fading source, S1, GCN 2477) of
RA: 08:02:30.190, Dec: -39:51:04.05
The 1 sigma error radius is 0.7" (including the residual 0.5" systematic
error from the correlation that is observed in the 1XMM catalogue).
This is consistent with the centre of the galaxy (z=0.105) reported by
Hsia et al. (GCN 2470) and by Bloom et al. (GCN 2481) and Prochaska et al.
(GCN 2482) and can be consistent with the radio source reported by Frail
(GCN 2473) if their systematic offset is >~0.5" as suggested by (Soderberg
et al. GCN 2483).
- XMM
Press Release on X-ray dust ring
- GCN notice #2493
J. Hjorth (U. Copenhagen), J. Gorosabel (IAA-CSIC/STScI), B. L. Jensen
(U. Copenhagen), J. P. U. Fynbo (U. Aarhus), M. I. Andersen (AIP),
J. R. Rasmussen (U. Aarhus), T. H. Dall (ESO), D. Bersier (STScI),
D. Watson, K. Pedersen, P. Jakobsson, and H. Pedersen (U. Copenhagen) report:
"We have observed the INTEGRAL error box of GRB 031203 (Gotz et al. GCN #2459)
with the Danish 1.5-m telescope at La Silla. We have obtained ~50 min I-band
exposures at five epochs between Dec 5.6 and Dec 13.6 UT in good seeing
conditions (~ 0.8"). We have performed both SExtractor photometry and
PSF-matched subtraction of the galaxy (Hsia et al. GCN #2470; Prochaska
et al. GCN #2475) coincident with the VLA radio (Frail GCN #2473; Soderberg
et al. GCN #2483) and XMM-Newton X-ray (Santos-Lleo & Calderon GCN #2464;
Rodriguez-Pascual et al. GCN #2474; Tedds et al. GCN #2490) error circles.
We find no evidence for significant variability above a level of 0.02 mag.
The PSF-matched subtraction did not reveal significant residuals either. We
therefore cannot confirm the reported variability (Bailyn et al. GCN #2486).
Assuming a foreground reddening of A_I = 2.01 mag (Schlegel et al. 1998),
these data points rule out a contribution from a SN1998bw-like supernova
redshifted to z = 0.105. There is still room for a fainter supernova, a more
distant supernova, or a supernova with a different lightcurve shape.
Continued monitoring at other observatories would help to constrain these
parameters. The monitoring has ended at the Danish 1.5-m telescope."
- GCN notice #2522
D.B. Fox, A.M. Soderberg, and S.R. Kulkarni (Caltech), with D. Frail
(NRAO) report:
"We have observed the X-ray afterglow of GRB031203 (Tedds et al., GCN
2490) with the Chandra X-ray Observatory, in a single 21.6 ksec
exposure beginning at 21:35 UT on 22 January 2004 (mean epoch 49.1
days post-burst). At the XMM position derived by Tedds et al. (GCN
2490) we observe a single point-like source with a net count rate of
0.56 +/- 0.16 counts per ksec. Converting this count rate into a flux
using the power-law (index 1.7) spectrum found by Vaughan et al. (GCN
2489), and assuming a hydrogen column of 6.2E+21 cm**-2, we find a
2-10 keV X-ray flux of approximately 6.4E-15 erg cm**-2 s**-1. This
corresponds to a power-law decay from the last epoch of XMM
observations (approx. 3.6 days post-burst) of index alpha = -1.0 +/-
0.1."
- GCN notice #2544
D. Bersier, J. Rhoads, A. Fruchter, J. M. Castro Cer=F3n,
L.-G. Strolger, S. Malhotra (STScI), J. Gorosabel (IAA-CSIC), A. Levan
(U. of Leicester), C. Kouveliotou, S. Patel (MSFC/NASA), M. Merrill
(NOAO), E. Gawiser, M. F. Duran, V. Gonzalez, (U. de Chile)
report:
Using the CTIO 4m telescope with MOSAIC2, we have obtained late-time
I-band imaging data of the field of GRB 031203 (Gotz et al, GCN 2459)
19, 25, and 77 days after the burst.
The afterglow found in X-ray (Schartel & Calderon, GCN 2464; Tedds et
al GCN 2490; Fox et al GCN 2522), radio (Frail, GCN 2473; Soderberg et
al GCN 2483) and IR (Tagliaferri et al GCN 2476) coincides with a
galaxy at a redshift z=3D0.105 (Prochaska et al GCN 2482). The
brightness of the galaxy at day 25 is I=3D19.25 (from a preliminary
calibration). This includes any contribution from a transient source
(afterglow and/or supernova). Matched-psf image subtraction (Alard,
2000, A&AS, 144, 363) reveals a fading source at this position,
between days 25 and 77, whereas there is no variation between days 19
and 25. Photometry via psf-fitting confirms this. The change in
magnitude of the "galaxy+variable source" between days 25 and 77 is
0.26 mag. Given the faintness of the afterglow at early times, and
the likelihood that the afterglow will have faded significantly at
the times of our measurements, we tentatively interpret this variable
source as a supernova.
The observed decay sets a lower limit on the magnitude at day 25 (near
I-band maximum in rest frame). The true brightness of the SN must be
greater than the flux difference between the two images, which
corresponds to I=3D20.94 +/- 0.08. Assuming an extinction of A_I=3D1.76
and a redshift z=3D0.105, this corresponds to a luminosity of -19.25,
which is very close to the maximum brightness of SN1998bw. If we were
to assume that the light curve of this object behaves as SN1998bw,
then the difference between these two times would underestimate the
true luminosity by 35%.
- GCN notice #2545
G. Tagliaferri, D. Malesani, G. Chincarini, S. Covino, D. Fugazza, M.
Della Valle, L.A. Antonelli, S. Campana, A. Cucchiara, P. D'Avanzo, F.
Fiore, G.L. Israel, D. Lazzati, A. Simoncelli, L. Stella, K. Stamatis,
F.M. Zerbi, on behalf of a larger collaboration, report:
Continuous monitoring of the host galaxy of the INTEGRAL GRB 031203
(Gotz et al., GCN 2459; Prochaska et al., GCN 2475) has been performed
with the ESO telescopes at Paranal and La Silla. We acquired several
exposures in the optical and NIR bands during the period December 03 -
March 01 (up to three months after the high-energy event).
We confirm the variability reported by Bersier et al. (GCN 2544). The
variability pattern is fully consistent with the evolution of a
98bw-like SN at z=0.105 (as measured in our spectra and in agreement
with Prochaska et al., GCN 2482), peaking approximately 20 days after
the burst in the R band. The contribution of such emission is roughly
30% of that of the host galaxy, as determined from the late-time photometry.
Spectra with the VLT were taken on Dec 20, Dec 30 and Mar 01 (17, 27,
and 90 days after the GRB respectively) in an attempt to fully
characterise the observed variability. Subtraction of the late-time
spectrum (taken 90 days after the GRB) from the spectra taken close to
the maximum of the rebrightening reveals the emergence of a spectrum
closely resembling that of SN 1998bw. We therefore conclude that the
observed rebrightening is due to a supernova (Malesani et al. in
preparation).
We thank the staff at the ESO telescopes (both Paranal and La Silla) for
the extensive work in this campaign, and in particular Malvina Billeres,
Olivier Hainaut, Swetlana Hubrig, Chris Lidman, Gianni Marconi, and
Thomas Szeifert.
This message may be cited.
- astro-ph/0511186 from 7 Nov 2005 1
Tiengo: Dust-scattered X-ray halos around gamma-ray bursts: GRB 031203 revisited
Scattering by interstellar dust grains can produce time variable X-ray halos
around gamma-ray bursts (GRB). In particular, an X-ray expanding ring is
expected when a short pulse of X-ray radiation is scattered by a narrow layer
of dust in our Galaxy. We present a new method to detect and analyze dust
scattering expanding rings around gamma-ray bursts, using as an example
XMM-Newton data of GRB 031203. Consistent with previous reports (Vaughan et al.
2004), we find that the two expanding rings observed in this burst are due to
dust unevenly distributed in two layers at distances of 870 and 1384 pc, with
the more distant one responsible for 70% of the total optical depth. Our
modelling of the rings indicates that the prompt X-ray emission of GRB 031203
was consistent with a power law spectrum with photon index $\Gamma$=2.1$\pm$0.2
and 1-2 keV fluence of (3.6$\pm$0.2)$\times10^{-7}$ erg cm$^{-2}$. Thanks to
the sensitivity of our technique, we discovered an expanding ring around
another burst recently observed with XMM-Newton, GRB 050713A. In this case the
dust layer is located at a distance of 364 pc and we derive a GRB fluence of
(1.2$\pm$0.3)$\times10^{-7}$ erg cm$^{-2}$ (1-2 keV). A search for similar
halos in other twelve bursts observed with XMM-Newton gave negative results.
- astro-ph/0601710 from 31 Jan 2006
Ruffini: Theoretical Interpretation of GRB 031203 and URCA-3
We present an analysis of the late time X-ray emission (URCA-3) connected
with GRB 031203 and SN 2003lw.
- astro-ph/0603516 from 20 Mar 2006
Mazzali: Models for the Type Ic Hypernova SN 2003lw associated with GRB 031203
The Gamma-Ray Burst 031203 at a redshift z=0.1055 revealed a highly reddened
Type Ic Supernova, SN 2003lw, in its afterglow light. This is the third well
established case of a link between a long-duration GRB and a type Ic SN. The SN
light curve is obtained subtracting the galaxy contribution and is modelled
together with two spectra at near-maximum epochs. A red VLT grism 150I spectrum
of the SN near peak is used to extend the spectral coverage, and in particular
to constrain the uncertain reddening, the most likely value for which is
E_{G+H}(B-V) about 1.07 +/- 0.05. Accounting for reddening, SN 2003lw is about
0.3 mag brighter than the prototypical GRB-SN 1998bw. Light curve models yield
a 56Ni mass of about 0.55 solar mass. The optimal explosion model is somewhat
more massive (ejecta mass about 13 solar mass) and energetic (kinetic energy
about 6 times 10^52 erg) than the model for SN 1998bw, implying a massive
progenitor (40 - 50 solar mass). The mass at high velocity is not very large
(1.4 solar mass above 30000 km/s, but only 0.1 solar mass above 60000 km/s),
but is sufficient to cause the observed broad lines. The similarity of SNe
2003lw and 1998bw and the weakness of their related GRBs, GRB031203 and
GRB980425, suggest that both GRBs may be normal events viewed slightly off-axis
or a weaker but possibly more frequent type of GRB.
- astro-ph/0605431 from 17 May 2006
Ghisellini: Are GRB 980425 and GRB 031203 real outliers or twins of GRB 060218?
GRB 980425 and GRB 031203 are apparently two outliers with respect to the
correlation between the isotropic equivalent energy E_iso emitted in the prompt
radiation phase and the peak frequency E_peak of the spectrum in a vF(v)
representation (the so-called Amati relation). We discuss if these two bursts
are really different from the others or if their location in the E_iso-E_peak
plane is the result of other effects, such as viewing them off-axis, or through
a scattering screen, or a misinterpretation of their spectral properties. The
latter case seems particularly interesting after GRB 060218, that, unlike GRB
031203 and GRB 980425, had a prompt emission detected both in hard and soft
X-rays which lasted ~2800 seconds. This allowed to determine its E_peak and
total emitted energy. Although it shares with GRB 031203 the total energetics,
it is not an outlier with respect to the Amati correlation. We then investigate
if a hard-to-soft spectral evolution in GRB 031203 and GRB 980425, consistent
with all the observed properties, can give rise to a time integrated spectrum
with an E_peak consistent with the Amati relation.
- astro-ph/0605494 from 19 May 2006
Sazonov: Constraints on the late X-ray emission from the low-energy GRB 031203: INTEGRAL data
Comparison of the INTEGRAL upper limits on the hard X-ray flux before and
after the low-energy GRB 031203 with the XMM measurements of the dust-scattered
radiation at lower energies suggests that a significant fraction of the total
burst energy could be released in the form of soft X-rays at an early afterglow
stage with a characteristic duration of ~100-1000s. The overall time evolution
of the GRB 031203 afterglow may have not differed qualitatively from the
behavior of standard (i.e., more intense) bursts studied by the SWIFT
observatory. The available data also admit the possibility that the
dust-scattered radiation was associated with an additional soft component in
the spectrum of the gamma-ray burst itself.
- astro-ph/0702225 from 8 Feb 2007
Margutti: Spectroscopical Study of the Host Galaxy of GRB031203
We revisit the host galaxy of GRB031203 using a set of spectra obtained with
VLT. Assuming a Galactic color excess E(B-V)=0.72 (mag)in the direction of the
burst,we derive an internal extinction of about 0.4 (mag). After correcting for
reddening, we find an electronic density of 156 cm^{-3} and a temperature of
12443(K). With an ISM dominated by photo-ionization, we estimate a metallicity
of 12+Log[O/H]=8.12 and a star formation rate of 12.3 (M_{o}yr^{-1}). This
galaxy does not host a clearly detectable population of WR stars.
- 0705.2456from 16 May 2007
Ruffini: The role of GRB 031203 in clarifying the astrophysical GRB scenario
Abstract: The luminosity and the spectral distribution of the afterglow of GRB 031203
have been presented within our theoretical framework, which envisages the GRB
structure as composed by a proper-GRB, emitted at the transparency of an
electron-positron plasma with suitable baryon loading, and an afterglow
comprising the "prompt emission" as due to external shocks. In addition to the
GRB emission, there appears to be a prolonged soft X-Ray emission lasting for
10^6-10^7 seconds followed by an exponential decay. This additional source has
been called by us URCA-3. It is urgent to establish if this component is
related to the GRB or to the Supernova (SN). In this second case, there are two
possibilities: either the interaction of the SN ejecta with the interstellar
medium or, possibly, the cooling of a young neutron star formed in the SN
2003lw process. The analogies and the differences between this triptych GRB
031203 / SN 2003lw / URCA-3 and the corresponding ones GRB 980425 / SN 1998bw /
URCA-1 and GRB 030329 / SN 2003dh / URCA-2, as well as GRB 060218 / SN 2006aj
are discussed.
- 0804.2821from 17 Apr 2008
Bianco: Theoretical interpretation of luminosity and spectral properties of GRB 031203
Abstract: We show how an emission endowed with an instantaneous thermal spectrum in the
co-moving frame of the expanding fireshell can reproduce the time-integrated
GRB observed non-thermal spectrum. An explicit example in the case of GRB
031203 is presented.
- 1112.3462 from 16 Dec 11
Rodrigo Negreiros et al.: Cooling of young neutron stars in GRB associated to Supernova
Recent observations of the late ($t=10^8$--$10^9$ s) emission of Supernovae associated to GRBs (GRB-SN) show a distinctive emission in the
X-ray regime consistent with temperatures $10^7$--$10^8$ K. Similar features have been also observed in the two Type Ic SN 2002ap and SN 1994I,
not associated to GRBs. We advance the possibility that the late X-ray emission observed in GRB-SN and in isolated SN is associated to a hot
neutron star (NS) just formed in the SN event, here defined as a neo-NS. We discuss the thermal evolution of neo-NS in the age regime that
spans from $\sim 1$ minute (just after the proto-NS phase) up to <10-100 yr. We examine the key factor governing the neo-NS cooling emphasizing
on the neutrino emission. A phenomenological heating source and new boundary conditions are introduced to mimic the high temperature of the
atmosphere for young NSs. We thus match the neo-NS luminosity to the late X-ray emission of the GRB-SN events: URCA-1 in GRB980425-SN1998bw,
URCA-2 in GRB030329-SN2003dh, and URCA-3 in GRB031203-SN2003lw. By calibrating our additional heating source at early times to $\sim
10^{12}$--$10^{15}$ erg/g/s, we find a striking agreement of the luminosity obtained from the cooling of neo-NSs with the prolonged
($t=10^{8}$--$10^{9}$ s) X-ray emission observed in GRB-SN. It seems appropriate to revise the boundary conditions usually used in the thermal
cooling theory of NSs, in order to match the proper conditions of the atmosphere at young ages. Additional heating processes not yet studied
within this context, e.g. e+e- pair creation by overcritical fields and nuclear fusion and fission energy release, might also take place under
such conditions and deserve further analysis. The observation of GRB-SN has evidenced the possibility of witnessing the thermal evolution of
neo-NSs. A new campaign of dedicated observations of GRB-SN and isolated Type Ic SN is recommended.
- 1406.2599 from 11 Jun 14
M. Symeonidis et al.: Herschel/PACS Observations of the Host Galaxy of GRB 031203
We present Herschel/PACS observations of the nearby (z=0.1055) dwarf galaxy that has hosted the long gamma ray burst (LGRB) 031203. Using the
PACS data we have been able to place constraints on the dust temperature, dust mass, total infrared luminosity and infrared-derived
star-formation rate (SFR) for this object. We find that the GRB host galaxy (GRBH) 031203 has a total infrared luminosity of 3x10^10 L_sun
placing it in the regime of the IR-luminous galaxy population. Its dust temperature and specific SFR are comparable to that of many
high-redshift (z=0.3-2.5) infrared (IR)-detected GRB hosts (T_dust>40K ; sSFR>10 Gyr^-1), however its dust-to-stellar mass ratio is lower than
what is commonly seen in IR-luminous galaxies. Our results suggest that GRBH 031203 is undergoing a strong starburst episode and its dust
properties are different to those of local dwarf galaxies within the same metallicity and stellar mass range. Furthermore, our measurements
place it in a distinct class to the well studied nearby host of GRB 980425 (z=0.0085), confirming the notion that GRB host galaxies can span a
large range in properties even at similar cosmological epochs, making LGRBs an ideal tool in selecting samples of star-forming galaxies up to
high redshift.
- 1512.01303 from 7 Dec 15
A. Corsi et al.: Radio observations of a sample of broad-lined type Ic supernovae discovered by PTF/iPTF: A search for relativistic explosions
Long duration gamma-ray bursts are thought to be a rare subclass of stripped-envelope core-collapse supernovae that launch collimated
relativistic outflows (jets). All gamma-ray-burst-associated supernovae are spectroscopically of Type Ic with broad lines, but the fraction of
broad-lined Type Ic supernovae harboring low-luminosity gamma-ray-bursts remains largely unconstrained. Some supernovae should be accompanied
by off-axis gamma-ray burst jets that remain invisible initially, but then emerge as strong radio sources (as the jets decelerate). However,
this critical prediction of the jet model for gamma-ray bursts has yet to be verified observationally. Here, we present K. G. Jansky Very Large
Array radio observations of 15 broad-lined supernovae of Type Ic discovered by the Palomar Transient Factory in an untargeted manner. Most of
the supernovae in our sample exclude radio emission observationally similar to that of the radio-loud, relativistic SN 1998bw. We thus
constrain the fraction of 1998bw-like broad-lined Type Ic supernovae to be <= 14%. Most of the events in our sample also exclude off-axis jets
similar to GRB 031203 and GRB 030329, but we cannot rule out off-axis gamma-ray-bursts expanding in a low-density wind environment. Three
supernovae show late-time radio emission compatible with average speeds >~ 0.3c, on the dividing line between relativistic and "ordinary"
supernovae. Based on these detections, we estimate that <= 45% of the broad-lined Type Ic supernovae in our sample may harbor off-axis
gamma-ray-bursts expanding in media with densities in the range probed by this study.
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