搜索结果: 1-15 共查到“天体物理学 GRB”相关记录19条 . 查询时间(0.066 秒)
A double component in GRB 090618: a proto-black hole and a genuinely long GRB
double component GRB 090618 proto-black hole GRB
2012/2/23
The joint X and gamma-ray observations of GRB 090618 by a large number of satellites offer an unprecedented possibility of testing crucial aspects of theoretical models. In particular, it allows us to...
Do Fermi-LAT observations really imply very large Lorentz factors in GRB outflows ?
gamma-ray burst: general gamma-ray burst: individual: GRB 080916C radiative transfer radiation mechanisms: non-thermal
2011/10/20
Recent detections of GeV photons in a few GRBs by Fermi-LAT imply huge bulk Lorentz factors to avoid a large gamma gamma optical depth at high energy. Estimates can be as high as Gamma ~ 1000 in the m...
Peculiarly Narrow SED of GRB 090926B with MAXI and Fermi/GBM
gamma rays: bursts — methods: data analysis
2011/10/19
The monitor of all-sky X-ray image (MAXI) Gas Slit Camera (GSC) on the International Space Station (ISS) detected a gamma-ray burst (GRB) on 2009, September 26, GRB\,090926B. This GRB had extremely ha...
Constraining GRB Emission Physics with Extensive Early-Time, Multiband Follow-up
Constraining Emission Physics Extensive Early-Time Multiband Follow-up
2011/10/10
Understanding the origin and diversity of emission processes responsible for Gamma-ray Bursts (GRBs) remains a pressing challenge. While prompt and contemporaneous panchromatic observations have the p...
WIDGET: System Performance and GRB Prompt Optical Observations
WIDGET System Performance GRB Prompt Optical Observations
2011/1/10
The WIDeField telescope for Gamma-ray burst Early Timing (WIDGET) is used for a fully automated, ultra-wide-field survey aimed at detecting the prompt optical emission associated with Gamma-ray Bursts...
The local energy production rates of GRB photons and of UHECRs
The local energy production rates GRB photons UHECRs
2011/1/10
In a recent analysis it was found that the local (z=0) rate at which gamma-ray bursts (GRBs) produce energy in 1 MeV photons, Q_GRB(z=0), is 300 times lower than the local energy production rate in ul...
Detection of a Thermal Spectral Component in the Prompt Emission of GRB 100724B
Detection of a Thermal Spectral Component in the Prompt Emission of GRB 100724B
2011/1/10
Observations of GRB 100724B with the Fermi Gamma-Ray Burst Monitor (GBM) find that the spectrum is dominated by the typical Band functional form, which is usually taken to represent a non-thermal emis...
GRB spectral parameter modeling
acceleration of particles shock waves turbulence galaxies: jets radiation mecha-nisms non-thermal magnetic fields
2010/11/9
Fireball model of the gamma-ray bursts (GRBs) predicts generation of numerous internal shocks, which efficiently accelerate charged particles and generate relatively small-scale stochastic magnetic an...
Aims. We report on a detailed study of the optical afterglow of GRB 061121 with our original time-series photometric data. In conjunction with X-ray observations, we discuss the origin of its optical ...
GRB 050502B optical afterglow: a jet break at high redshift
Gamma rays bursts observations individual GRB 050502B
2010/11/9
Aims. GRB050502B is well known for the very bright flare displayed in its X-ray light curve. Despite extensive studies, however, the optical light curve has never been discussed and its redshift is un...
Photometric redshifts for GRB afterglows from GROND and Swift/UVOT
gamma rays bursts Techniques photometric
2010/11/11
Aims. We present a framework to obtain photometric redshifts (photo-zs) for gamma-ray burst afterglows. Using multi-band photometry from GROND and Swift/UVOT, photo-zs are derived for five GRBs for wh...
The missing gas problem in GRB host galaxies: evidence for a highly ionised component
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/28
There is considerable discrepancy between the amount of X-ray absorption and that inferred from optical (rest frame UV) as measured along gamma-ray burst (GRB) sight lines, with the former being typic...
A nearby GRB host prototype for z~7 Lyman-break galaxies: Spitzer-IRS and X-shooter spectroscopy of the host galaxy of GRB031203
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/28
Gamma-ray burst (GRB) host galaxies have been studied extensively in optical photometry and spectroscopy. Here we present the first mid-infrared spectrum of a GRB host, HG031203. It is one of the near...
Searching for Needles in Haystacks - Using the Fermi/GBM to find GRB gamma-rays with the Fermi/LAT Detector
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/27
From the launch of the Fermi Gamma-ray Space Telescope to July 9, 2010, the Gamma-ray Burst Monitor (GBM) has detected 497 probable GRB events. Twenty-two of these satisfy the simultaneous requirement...
Searching for Needles in Haystacks - Looking for GRB gamma-rays with the Fermi/LAT Detector
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/27
Since the launch of the Fermi Gamma-ray Space Telescope on June 11, 2008, 55 gamma-ray bursts (GRBs) have been observed at coordinates that fall within 66^\circ of the Fermi Large Area Telescope (LAT)...