搜索结果: 1-15 共查到“天文学 GRB”相关记录27条 . 查询时间(0.093 秒)
2024年5月27日,中国科学院紫金山天文台研究团队利用费米卫星大面积伽马射线望远镜(Fermi-LAT)的观测数据,发现了一个来自于GRB 221009A方向的400 GeV光子,利用这一观测发现实现了星系际磁场强度的首次推断。相关研究结果以“A delayed 400 GeV photon from GRB 221009A and implication on the intergalacti...
近期,《天体物理学杂志》在线发表了中国科学院云南天文台博士刘杰英和研究员毛基荣的研究成果。他们对超长伽玛射线暴源——GRB 130925A余辉的X射线热辐射起源进行了理论解释,认为该源10 keV以上的热X射线辐射起源于富金属/尘埃星风中的热轫致辐射过程。伽玛射线暴是宇宙中最为剧烈的爆发现象,辐射持续时间从几毫秒到几千秒不等。爆发阶段的辐射一般被称为瞬时辐射,而爆发结束后在更低能段(如X射线、光学...
引力波探测器LIGO/Virgo的主要观测对象除业已探测到的双黑洞并合事件(例如GW150914)外还包括中子星并合事件,也就是“双中子星的并合”或者是“恒星级质量黑洞与中子星的并合”。中子星并合过程不但会发射出强的引力波辐射,还伴随剧烈的电磁辐射,也就是所谓的引力波电磁对应体。其中一类引人瞩目的引力波电磁对应体是Li-Paczynski macronova(巨新星),它源自中子星并合过程中的抛射...
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...
Detectability of GRB optical afterglows with Gaia satellite
Detectability optical Gaia satellite
2011/10/9
With the launch of Gaia satellite, detection of many different types of transient sources will be possible, one of them being optical afterglows of gamma-ray bursts (GRBs). Using the knowledge of the ...
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...
GRB 070125 and the environments of spectral-line poor afterglow absorbers
gamma-ray burst: individual: GRB070125
2011/10/11
GRB 070125 is among the most energetic bursts detected and the most extensively observed so far. Nevertheless, unresolved issues are still open in the literature on the physics of the afterglow and on...
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...
Evidence for mild deviation from power-law distribution of electrons in relativistic shocks: GRB 090902B
radiation mechanisms: non-thermal - methods: analytical - methods: numerical- gamma-rays: bursts, theory - gamma-ray burst: individual: GRB090902B
2011/9/29
Many previous studies have determined that the long lasting emission at X-ray, optical and radio wavelengths from gamma-ray bursts (GRBs), called the afterglow, is likely produced by the external forw...
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 ...