|
Publications
Multiwavelength analysis of the intriguing GRB 061126: the reverse shock scenario and magnetization
Authors:
A. Gomboc et al.
Appeared
in: Astrophysical Journal, Volume 687, pp. 443-455 (2008)
We present a detailed study of the prompt and afterglow emission from Swift GRB 061126 using BAT, XRT, UVOT data and multi-color optical imaging from ten ground-based telescopes. GRB 061126 was a long burst, T(90) = 191 s, with four overlapping peaks in its gamma-ray light curve. The X-ray afterglow, observed from 26 min to 20 days after the burst, shows a simple power-law decay with alpha(X) = 1.290 +/- 0.008. Optical observations presented here cover the time range from 258 s (Faulkes Telescope North) to 15 days (Gemini North) after the burst; the decay rate of the optical afterglow shows a steep-to-shallow transition (from alpha1 = 1.48 +/- 0.06 to alpha2 = 0.89 +/- 0.03) approximately 12 min after the burst. We suggest the early, steep component is due to a reverse shock and show that the original ejecta from the central engine is highly magnetized. The optical light curve implies a late-time break at about 1.5 days after the burst, while there is no evidence of the simultaneous break in the X-ray light curve. We model the broad band emission and show that some afterglow characteristics (the steeper decay in X-ray and the shallow spectral index from optical to X-ray) are difficult to explain in the framework of the standard fireball model. This might imply that the X-ray afterglow is due to an additional emission process, such as late time central engine activity rather than blast-wave shock emission. Possible chromatic break at 1.5 days after the burst would give support to the additional emission scenario.
The Early-time Optical Properties of Gamma-Ray Burst Afterglows
Authors:
A. Melandri et al.
Appeared
in: Astrophysical Journal, Volume 686, pp. 1209-1230 (2008)
We present a multiwavelength analysis of 63 Gamma-Ray Bursts observed with the world's three largest robotic optical telescopes, the Liverpool and Faulkes Telescopes (North and South). Optical emission was detected for 24 GRBs with brightnesses ranging from R = 10 to 22 mag in the first 10 minutes after the burst. By comparing optical and X-ray light curves from t = 100 to about 1,000,000 seconds, we introduce four main classes, defined by the presence or absence of temporal breaks at optical and/or X-ray wavelengths. While 15/24 GRBs can be modelled with the forward-shock model, explanation of the remaining nine is very challenging in the standard framework even with the introduction of energy injection or an ambient density gradient. Early X-ray afterglows, even segments of light curves described by a power-law, may be due to additional emission from the central engine. 39 GRBs in our sample were not detected and have deep upper limits (R < 22 mag) at early time. Of these, only ten were identified by other facilities, primarily at near infrared wavelengths, resulting in a dark burst fraction of about 50%. Additional emission in the early time X-ray afterglow due to late-time central engine activity may also explain some dark bursts by making the bursts brighter than expected in the X-ray band compared to the optical band.
GRB 061121: Broadband Spectral Evolution through the Prompt and Afterglow Phases of a Bright Burst
Authors:
K. L. Page et al.
Appeared
in: Astrophysical Journal, Volume 663, pp. 1125-1138 (2007)
Swift triggered on a precursor to the main burst of GRB 061121 (z = 1.314), allowing observations to be made from the optical to gamma-ray bands. Many other telescopes, including Konus-Wind, XMM-Newton, ROTSE, and the Faulkes Telescope North, also observed the burst. The gamma-ray, X-ray, and UV/optical emission all showed a peak ~75 s after the trigger, although the optical and X-ray afterglow components also appear early on, before or during the main peak. Spectral evolution was seen throughout the burst, with the prompt emission showing a clear positive correlation between brightness and hardness. The SED of the prompt emission, stretching from 1 eV up to 1 MeV, is very flat, with a peak in the flux density at ~ 1 keV. The optical to X-ray spectra at this time are better fitted by a broken, rather than single, power law, similar to previous results for X-ray flares. The SED shows spectral hardening as the afterglow evolves with time. This behavior might be a symptom of self-Comptonization, although circumstellar densities similar to those found in the cores of molecular clouds would be required. The afterglow also decays too slowly to be accounted for by the standard models. Although the precursor and main emission show different spectral lags, both are consistent with the lag-luminosity correlation for long bursts. GRB 061121 is the instantaneously brightest long burst yet detected by Swift. Using a combination of Swift and Konus-Wind data, we estimate an isotropic energy of 2.8E53 ergs over 1 keV-10 MeV in the GRB rest frame. A probable jet break is detected at ~200,000 s, leading to an estimate of ~1E51 ergs for the beaming-corrected gamma-ray energy.
The Angstrom Project Alert System: Real-Time Detection of Extragalactic Microlensing
Authors:
M. J. Darnley et al.
Appeared
in: Astrophysical Journal, Volume 661, pp. L45-L48 (2007)
The Angstrom Project is undertaking an optical survey of stellar microlensing events across the bulge region of the Andromeda galaxy (M31) using a distributed network of 2 m class telescopes. The Angstrom Project Alert System (APAS) has been developed to identify candidate microlensing and transient events in real time, using data from the Liverpool and Faulkes North robotic telescopes. This is the first time that real-time microlensing discovery has been attempted outside of the Milky Way and its satellite galaxies. The APAS is designed to enable follow-up studies of M31 microlensing systems, including searches for gas giant planets in M31. Here we describe the APAS, and we present a few example light curves obtained during its commissioning phase that clearly demonstrate its real-time capability to identify microlensing candidates as well as other transient sources.
The Remarkable Afterglow of GRB 061007: Implications for Optical Flashes and GRB Fireballs
Authors:
C. G. Mundell et al.
Appeared
in: Astrophysical Journal, Volume 660, pp. 489-495 (2007)
We present a multiwavelength analysis of Swift GRB 061007. The 2 m robotic Faulkes Telescope South began observing 137 s after the onset of the gamma-ray emission, when the optical counterpart was already decaying from R~10.3 mag, and continued observing for the next 5.5 hr. These observations begin during the final gamma-ray flare and continue through and beyond a long, soft tail of gamma-ray emission whose flux shows an underlying simple power-law decay identical to that seen at optical and X-ray wavelengths, with temporal slope alpha~1.7. This remarkably simple decay in all of these bands is rare for Swift bursts, which often show much more complex light curves. We suggest the afterglow emission begins as early as 30-100 s and is contemporaneous with the ongoing variable prompt emission from the central engine, but originates from a physically distinct region dominated by the forward shock. The observed multiwavelength evolution of GRB 061007 is explained by an expanding fireball whose optical, X-ray, and late-time gamma-ray emission is dominated by emission from a forward shock with typical synchrotron frequency, um, that is already below the optical band as early as t=137 s and a cooling frequency, uc, above the X-ray band to at least t=105 s. In contrast, the typical frequency of the reverse shock lies in the radio band at early time. We suggest that the unexpected lack of bright optical flashes from the majority of Swift GRBs may be explained with a low um originating from small microphysics parameters, e and B. Finally, the optical light curves imply a minimum jet opening angle I=4.7deg, and no X-ray jet break before t~106 s makes GRB 061007 a secure outlier to spectral energy correlations.
The circumburst environment of a FRED GRB: study of the prompt emission and X-ray/optical afterglow of GRB 051111
Authors:
C. Guidorzi et al.
Appeared
in: Astronomy and Astrophysics, Volume 463, pp. 539-550 (2007)
Aims.We report a multi-wavelength analysis of the prompt emission and early afterglow of GRB 051111 and discuss its properties in the context of current fireball models. Methods: The detection of GRB 051111 by the Burst Alert Telescope on-board Swift triggered early BVRi' observations with the 2-m robotic Faulkes Telescope North in Hawaii, as well as X-ray observations with the Swift X-Ray Telescope. Results: The prompt gamma-ray emission shows a classical FRED profile. The optical afterglow light curves are fitted with a broken power law, with alpha1=0.35 to alpha2=1.35 and a break time around 12 min after the GRB. Although contemporaneous X-ray observations were not taken, a power law connection between the gamma-ray tail of the FRED temporal profile and the late XRT flux decay is feasible. Alternatively, if the X-ray afterglow tracks the optical decay, this would represent one of the first GRBs for which the canonical steep-shallow-normal decay typical of early X-ray afterglows has been monitored optically. We present a detailed analysis of the intrinsic extinction, elemental abundances and spectral energy distribution. From the absorption measured in the low X-ray band we find possible evidence for an overabundance of some alpha elements such as oxygen, [O/Zn] = 0.7 +/- 0.3, or, alternatively, for a significant presence of molecular gas. The IR-to-X-ray Spectral Energy Distribution measured at 80 min after the burst is consistent with the cooling break lying between the optical and X-ray bands. Extensive modelling of the intrinsic extinction suggests dust with big grains or grey extinction profiles. The early optical break is due either to an energy injection episode or, less probably, to a stratified wind environment for the circumburst medium.
A Review of Early-Time Optical Follow-ups with 2-m Robotic Telescopes
Authors:
A. Gomboc et al.
Appeared
in: Astronomy and Astrophysics, Volume 463, pp. 539-550 (2007)
Aims.We report a multi-wavelength analysis of the prompt emission and early afterglow of GRB 051111 and discuss its properties in the context of current fireball models. Methods: The detection of GRB 051111 by the Burst Alert Telescope on-board Swift triggered early BVRi' observations with the 2-m robotic Faulkes Telescope North in Hawaii, as well as X-ray observations with the Swift X-Ray Telescope. Results: The prompt gamma-ray emission shows a classical FRED profile. The optical afterglow light curves are fitted with a broken power law, with alpha1=0.35 to alpha2=1.35 and a break time around 12 min after the GRB. Although contemporaneous X-ray observations were not taken, a power law connection between the gamma-ray tail of the FRED temporal profile and the late XRT flux decay is feasible. Alternatively, if the X-ray afterglow tracks the optical decay, this would represent one of the first GRBs for which the canonical steep-shallow-normal decay typical of early X-ray afterglows has been monitored optically. We present a detailed analysis of the intrinsic extinction, elemental abundances and spectral energy distribution. From the absorption measured in the low X-ray band we find possible evidence for an overabundance of some alpha elements such as oxygen, [O/Zn] = 0.7 +/- 0.3, or, alternatively, for a significant presence of molecular gas. The IR-to-X-ray Spectral Energy Distribution measured at 80 min after the burst is consistent with the cooling break lying between the optical and X-ray bands. Extensive modelling of the intrinsic extinction suggests dust with big grains or grey extinction profiles. The early optical break is due either to an energy injection episode or, less probably, to a stratified wind environment for the circumburst medium.
Anatomy of a dark burst - the afterglow of GRB 060108
Authors:
S. R. Oates et al.
Appeared
in: Monthly Notices of the Royal Astronomical Society, Volume 372, pp. 327-337 (2006)
We present a multiwavelength study of GRB 060108 - the 100th gamma-ray burst discovered by Swift. The X-ray flux and light curve (three segments plus a flare) detected with the X-ray Telescope are typical of Swift long bursts.
We report the discovery of a faint optical afterglow detected in deep BVRi'-band imaging obtained with the Faulkes Telescope North beginning 2.75 min after the burst. The afterglow is below the detection limit of the Ultraviolet/Optical Telescope within 100 s of the burst, while is evident in K-band images taken with the United Kingdom Infrared Telescope 45 min after the burst. The optical light curve is sparsely sampled. Observations taken in the R and i' bands can be fitted either with a single power-law decay in flux, F(t) = t^-a where a = 0.43 +/- 0.08, or with a two-segment light curve with an initial steep decay a1 < 0.88 +/- 0.2, flattening to a slope a2 = 0.31 +/- 0.12. A marginal evidence for rebrightening is seen in the i' band.
Deep R-band imaging obtained 12 d post-burst with the Very Large Telescope reveals a faint, extended object (R = 23.5mag) at the location of the afterglow. Although the brightness is compatible with the extrapolation of the slow decay with index a2, significant flux is likely due to a host galaxy. This implies that the optical light curve had a break before 12 d, akin to what observed in the X-rays.
We derive the maximum photometric redshift z < 3.2 for GRB 060108. We find that the spectral energy distribution at 1000 s after the burst, from the optical to the X-ray range, is best fitted by a simple power law, Fn = n^-b, with bOX = 0.54 and a small amount of extinction. The optical to X-ray spectral index (bOX) confirms GRB 060108 to be one of the optically darkest bursts detected. Our observations rule out a high redshift as the reason for the optical faintness of GRB 060108. We conclude that a more likely explanation is a combination of an intrinsic optical faintness of the burst, a hard optical to X-ray spectrum and a moderate amount of extinction in the host galaxy.
High level interfaces to the Robonet-1.0 Homogeneous Telescope Network
Author:
C. Mottram
Appeared
in: Il Nuovo Cimento (2006)
We summarise recent deep, rapid GRB follow-up observations using the RoboNet-1.0 network which comprises three fully-robotic 2-m telescopes, the Liverpool Telescope and the Faulkes Telescopes North and South. Observations begin automatically within minutes of receipt of a GRB alert and may continue for hours or days to provide well-sampled multi-colour light curves or deep upper limits. Our light curves show a variety of early afterglow behaviour, from smooth, simple or broken power laws to 'bumpy', for a wide range of optical brightness (from the unprecedented faint detections of GRB 060108 and GRB 060510B to classical bright ones). We discuss GRB 051111 as an example of how the combination of optical and X-ray light curves can provide insight into the circumburst environment, in particular the role played by intrinsic extinction soon after the burst.
Scheduling for Robonet-1 homogenous telescope network
Author:
S. N. Fraser
Appeared
in: Astronomische Nachrichten, Volume 327, pp. 779-782 (2006)
The Robonet-1 homogenous telescope network consists of 3 fully robotic 2 m class telescopes. I describe how the observation requests submitted by external users and automated user agents are selected for observation by the individual telescope schedulers.
The first cool rocky/icy exoplanet
Authors:
M. Dominik et al.
Appeared
in: Astronomy & Geophysics, Volume 47, pp. 3.25-3.30 (2006)
The recent discovery of the first cool, rocky/icy exoplanet around a mainsequence star provides the first observational hint that planets like Earth are common in the universe. It was detected using gravitational microlensing from data of three independent observing teams under the lead of PLANET (Probing Lensing Anomalies NETwork), operating a common microlensing campaign with the UK-based RoboNet project. In the coming years intense microlensing observations will determine the abundance of cool rocky/icy planets around M-dwarfs and therefore provide the first observational test of models of planet formation and migration on objects that share their evolutionary history with Earth and other planets on which life had a chance to develop.
Microlens
OGLE-2005-BLG-169 Implies That Cool Neptune-like Planets Are Common
Authors:
A. Gould et al.
Appeared
in: The Astrophysical Journal, Volume 644, pp. L37-L40 (2006)
We detect a Neptune mass ratio (q = 8E-5) planetary companion to the lens star in the extremely high magnification (A = 800) microlensing event OGLE-2005-BLG-169. If the parent is a main-sequence star, it has mass M = 0.5 Msolar, implying a planet mass of 13 Mearth and projected separation of 2.7 AU. When intensely monitored over their peak, high-magnification events similar to OGLE-2005-BLG-169 have nearly complete sensitivity to Neptune mass ratio planets with projected separations of 0.6-1.6 Einstein radii, corresponding to 1.6-4.3 AU in the present case. Only two other such events were monitored well enough to detect Neptunes, and so this detection by itself suggests that Neptune mass ratio planets are common. Moreover, another Neptune was recently discovered at a similar distance from its parent star in a low-magnification event, which are more common but are individually much less sensitive to planets. Combining the two detections yields 90% upper and lower frequency limits f = 0.38 over just 0.4 decades of planet-star separation. In particular, f > 16% at 90% confidence. The parent star hosts no Jupiter-mass companions with projected separations within a factor 5 of that of the detected planet. The lens-source relative proper motion is 7-10 mas/yr, implying that if the lens is sufficiently bight, I < 23.8, it will be detectable by the Hubble Space Telescope by 3 years after peak. This would permit a more precise estimate of the lens mass and distance and, so, the mass and projected separation of the planet. Analogs of OGLE-2005-BLG-169Lb orbiting nearby stars would be difficult to detect by other methods of planet detection, including radial velocities, transits, and astrometry.
Discovery
of a Cool Planet of 5.5 Earth Masses Through Gravitational
Microlensing
Authors:
J.-P. Beaulieu et al.
Appeared
in: Nature, Volume 439, pp. 437-440 (2006)
In
the favoured core-accretion model of formation of planetary
systems, solid planetesimals accumulate to build up planetary
cores, which then accrete nebular gas if they are sufficiently
massive. Around M-dwarf stars (the most common stars in our
Galaxy), this model favours the formation of Earth-mass to
Neptune-mass planets with orbital radii of 1 to 10 astronomical
units (AU), which is consistent with the small number of gas giant
planets known to orbit M-dwarf host stars. More than 170
extrasolar planets have been discovered with a wide range of
masses and orbital periods, but planets of Neptune's mass or less
have not hitherto been detected at separations of more than 0.15
AU from normal stars. Here we report the discovery of a 5.5
(+5.5/-2.7) M_earth planetary companion at a separation of 2.6
(+1.5/-0.6) AU from a 0.22 (+0.21/-0.11) M_solar M-dwarf star. (We
propose to name it OGLE-2005-BLG-390Lb, indicating a planetary
mass companion to the lens star of the microlensing event.) The
mass is lower than that of GJ876d, although the error bars
overlap. Our detection suggests that such cool, sub-Neptune-mass
planets may be more common than gas giant planets, as predicted by
the core accretion theory.
Rapid
GRB Follow-up with the 2-m Robotic Liverpool Telescope
Authors:
A. Gomboc et al.
Appeared
in: Interacting Binaries, AIP Proc 797, pp. 181-186 (2005)
We
present the capabilities of the 2-m robotic Liverpool Telescope
(LT), owned and operated by Liverpool John Moores University and
situated at ORM, La Palma. Robotic control and scheduling of the
LT make it especially powerful for observations in time domain
astrophysics including: (i) rapid response to Targets of
Opportunity: Gamma Ray Bursts, novae, supernovae, comets; (ii)
monitoring of variable objects on timescales from seconds to
years, and (iii) observations simultaneous or coordinated with
other facilities, both ground-based and from space. Following a
GRB alert from the Gamma Ray Observatories HETE-2, INTEGRAL and
Swift we implement a special over-ride mode which enables
observations to commence in about a minute after the alert,
including optical and near infrared imaging and spectroscopy. In
particular, the combination of aperture, site, instrumentation and
rapid response (aided by its rapid slew and fully-opening
enclosure) makes the LT excellently suited to help solving the
mystery of the origin of optically dark GRBs, for the
investigation of short bursts (which currently do not have any
confirmed optical counterparts) and for early optical spectroscopy
of the GRB phenomenon in general. We briefly describe the LT's key
position in the RoboNet-1.0 network of robotic telescopes.
The
Early Multicolor Afterglow of GRB 050502a: Possible Evidence for a
Uniform Medium with Density Clumps
Authors:
C. Guidorzi et al.
Appeared
in: Astrophysical Journal, Volume 630, Issue 2, pp. L121-L124
(2005)
The
2 m robotic Liverpool Telescope reacted promptly to the gamma-ray
burst GRB 050502a, discovered by INTEGRAL, and started observing 3
minutes after the onset of the burst. The automatic identification
of a bright afterglow with r'~15.8 mag triggered, for the first
time, an observation sequence in the BVr'i' filters during the
first hour after a GRB. Observations continued for ~1 day using
the RoboNet-1.0 network of 2 m
robotic telescopes. The light curve in all filters can be
described by a simple power law with index of 1.2 +/- 0.1. We find
evidence for a bump rising at t ~ 0.02 days in all filters. From the
spectrum and the light curve, we investigate different scenarios
and find possible evidence for a uniform circumburst medium with
clumps in density, as in the case of GRB 021004. Other
interpretations of such bumps, such as the effect of energy
injection through refreshed shocks or the result of a variable
energy profile, are less favored. The optical afterglow of GRB
050502a is likely to be the result of slow electron cooling, with
the optical bands lying between the synchrotron peak frequency and
the cooling frequency.
A
Jovian-Mass Planet in Microlensing Event OGLE-2005-BLG-071
Authors:
A. Udalski et al.
Appeared
in: Astrophysical Journal, Volume 628, Issue 2, pp. L109-L112
(2005)
We
report the discovery of a several-Jupiter–mass planetary
companion to the primary lens star in microlensing event
OGLE-2005-BLG-071. Precise (<1%) photometry at the peak of the
event yields an extremely high signal-to-noise ratio detection of
a deviation from the light curve expected from an isolated lens.
The planetary character of this deviation is easily and
unambiguously discernible from the gross features of the light
curve. Detailed modeling yields a tightly constrained planet-star
mass ratio of q = mp/M = 0.0071 ±
0.0003. This is the second robust detection of a planet with
microlensing, demonstrating that the technique itself is viable
and that planets are not rare in the systems probed by
microlensing, which typically lie several kiloparsecs toward the
Galactic center.
The
Liverpool Telescope
Author:
I. A. Steele
Appeared
in: Astronomische Nachrichten, Volume 325, Issue 6-8, pp. 519-521
(2004)
The
Liverpool Telescope is a 2.0 metre robotic telescope on La Palma.
It achieved first light in July 2003, and began science operations
in January 2004, with (supervised) robotic operation from April
2004. Unmanned operation is planned for October 2004. As a
national, common-user facility, the telescope must support over 50
science programmes and is equipped both with common user and
experiment specific instruments. As an example, the SupIRCam
instrument has been designed to obtain infrared light curves of
Type Ia supernovae. This instrument achieved first light in July
2004. From August 2004 the telescope participates in the
ROBONET-1.0 network of 2.0 metre
telescopes with the Faulkes Telescopes located in Hawaii and
Australia, executing coordinated observations of GRB and exoplanet
microlensing events.
Echo
Tomography of Black Hole Accretion Flows
Author:
K. Horne
Appeared
in: Future EUV, UV, and Visible Astrophysics Missions and
Instrumentation, SPIE Proc 4854, pp. 262-273 (2003)
We
discuss technologies for micro-arcsec echo mapping of black hole
accretion flows in Active Galactic Nuclei (AGN). Echo mapping
employs time delays, Doppler shifts, and photoionization physics
to map the geometry, kinematics, and physical conditions in the
reprocessing region close to a compact time-variable source of
ionizing radiation. Time delay maps are derived from detailed
analysis of variations in lightcurves at different wavelengths.
Echo mapping is a maturing technology at a stage of development
similar to that of radio inteferometry just before the VLA. The
first important results are in, confirming the basic assumptions
of the method, measuring the sizs of AGN emission line regions,
delivering dozens of black hole masses, and showing the promise of
the technique. Resolution limits with existing AGN monitoring
datasets are typically approximately 5 - 10 light days. This
should improve down to 1 - 2 light days in the next-generation
echo mapping experiments, using facilities like Kronos and Robonet
that are designed for and dedicated to sustained spectroscopic
monitoring. A light day is 0.4 micro-arcsec at a redshift of 0.1,
thus echo mapping probes regions 103 times smaller than
with VLBI, and 105 times smaller than with HST.)
Inherent
small telescope projects
Author:
P. A. Charles
Appeared
in: New Astronomy Reviews, Volume 45, Issue 1-2, pp. 23-25 (2001)
As
we stand on the verge of substantial access to the new generation
of giant telescopes (Gemini, VLT and others) it is timely to
consider the range of science that can be undertaken with the
substantial number of smaller telescopes that are spread around
the globe. While providing survey science input to the giant
telescopes, or simultaneous monitoring capability for space
missions, is a clearly important role (see previous
contributions), it should not be forgotten that there are still
many outstanding scientific programmes that can be undertaken on
smaller telescopes in their own right. There is a danger of these
opportunities being overlooked in the stampede to abandon the
smaller telescope `baggage' in the hope of acquiring access to
more giant telescope time. I will try to demonstrate that the most
effective and efficient use of all our telescope time requires
access to a broad range of complementary facilities. I will
therefore describe here some of the projects currently being
undertaken with smaller telescopes as well as some of those
planned for future facilities such as ROBONET.
Full
Journal Article
Circulars
from the Gamma ray bursts Coordinates Network
8699
(GRB081222A)
8508
(GRB081109A)
8475
(GRB081104)
8402
(GRB081024)
8333
(GRB081007)
8099
(GRB080810)
8076
(GRB080805)
8064
(GRB080804)
7963
(GRB080710)
7872
(GRB080613)
7788
(GRB080603)
7637
(GRB080320)
7636
(GRB080319A)
7626
(GRB080413B)
7625
(GRB080413A)
7526
(GRB080328)
7353
(GRB080303A)
7337
(GRB080229)
6964
(GRB071021)
6959
(GRB071021)
6848
(GRB071003)
6833
(GRB071001)
6758
(GRB070810B)
6727
(GRB070808)
6647
(GRB070721B)
6645
(GRB070721A)
6435
(GRB070521)
6334
(GRB070420)
6315
(GRB070419A)
6115
(GRB070220)
6077
(GRB070208)
5920
(GRB061210)
5857
(GRB061126)
5827
(GRB061121)
5709
(GRB061007)
5708
(GRB061007)
5700
(GRB061006)
5670
(GRB060930)
5633
(GRB060927)
5594
(GRB060923C)
5593
(GRB060923C)
5586
(GRB060923)
5579
(GRB060919)
5119
(GRB060512)
5103
(GRB060510B)
4889
(GRB060319)
4855
(GRB060219)
4738
(GRB060211)
4726
(GRB060210)
4693
(GRB060206)
4665
(GRB060204C)
4661
(GRB060204B)
4630
(GRB060202)
4566
(GRB060121)
4521
(GRB060116)
4504
(GRB060114)
4502
(GRB060108)
4447
(GRB060108)
4337
(GRB051211b)
4250
(GRB051111)
4035
(GRB050925)
3706
(GRB050730)
3625
(GRB050716)
3592
(GRB050713b)
3588
(GRB050713a)
3497
(GRB050528)
3437
(GRB050520)
3375
(GRB050505)
3351
(GRB050504)
3325
(GRB050502a)
3051
(GRB050215b)
3001
(GRB050128)
2852
(GRB041211)
2845
(GRB041211)
|