GRB 170817 A的短伽马射线暴(SGRB)被发现与一个双星中子星(BNS)合并有关。目前尚不确定是否所有SGRB都是由BNS合并引起的,也不确定BNS合并在什么条件下会引起SGRB。由于BNS合并可能导致SGRB,余辉观测也将提供一种独立于引力波观测的BNS合并率的替代测量。在Feng等人(2014)之前的工作中,使用各种无线电观测站和简单的通量阈值检测算法来考虑余辉检测的可行性。在这里,我们考虑一个更复杂的检测算法SGRB余辉,并提供一个现实的搜索,以获得一个更新的估计与加拿大氢强度测绘实验(CHIME)观测余辉的可能性的试验因素的估计。我们估计每年893和312余辉可以检测到使用$3 σ$置信水平阈值与两个喷流模型,一个半开角均匀分布在$6^\circ$到$30^\circ$,另一个均匀分布在$3^\circ$到$8^\circ$与中位数$6^\circ$。我们还发现,88%和98%,分别为每个射流开口分布的可检测的余辉是离轴的,这是孤儿余辉的候选人。我们的结果预测每年可检测到的源比早期的分析少,但证实了使用CHIME搜索余辉将有效限制天体物理合并率的基本结论。
英文摘要:
Short gamma-ray burst (SGRB) GRB 170817A was found to be related to a binary neutron star (BNS) merger. It is uncertain whether all SGRBs are caused by BNS mergers, and also under what conditions a BNS merger can cause a SGRB. As BNS mergers can cause SGRBs, afterglow observations will also provide an alternative measurement of the BNS merger rate independent of gravitational-wave observations. In previous work by Feng et al. (2014), the feasibility of the detection of afterglows was considered using a variety of radio observatories and a simple flux threshold detection algorithm. Here, we consider a more sophisticated detection algorithm for SGRB afterglows, and provide an estimate of the trials factors for a realistic search to obtain an updated estimate of the possibility of observing afterglows with the Canadian Hydrogen Intensity Mapping Experiment (CHIME). We estimate 893 and 312 afterglows per year can be detected using a $3 σ$ confidence level threshold with two jet models, one with half opening angle uniformly distributed in $6^\circ$ to $30^\circ$ and the other uniformly distributed in $3^\circ$ to $8^\circ$ with the median $6^\circ$. We also find 88% and 98%, respectively, of the detectable afterglows for each jet opening distribution are off-axis, which are candidates for orphan afterglows. Our result predicts fewer detectable sources per year than the earlier analysis, but confirms the essential conclusion that using CHIME to search for afterglows will be effective at constraining the astrophysical merger rate.
CHIME/Slow overview and pilot survey: A new backend to search for second-duration radio transients with the CHIME telescope
Tata Institute of Fundamental Research(塔塔基础研究所);Raman Research Institute(拉曼研究所);LUX, Observatoire de Paris, Université PSL, Sorbonne Université, CNRS(巴黎天文台,巴黎文理研究大学,索邦大学,法国国家科学研究中心);National Centre for Radio Astrophysics(国家射电天体物理中心);Indian Institute of Astrophysics(印度天体物理研究所);Anton Pannekoek Institute for Astronomy, University of Amsterdam(阿姆斯特丹大学安东·潘内克天文研究所);ASTRON, the Netherlands Institute for Radio Astronomy(荷兰射电天文研究所);York University(约克大学)
Exploring the connection between Fast Radio Bursts and binary neutron star mergers
University of Pisa(比萨大学);INFN - Pisa(意大利国家核物理研究所-比萨分部);INAF - Osservatorio Astronomico di Roma(意大利国家天体物理研究所罗马天文台);INAF - Osservatorio Astronomico di Brera(意大利国家天体物理研究所布里埃拉天文台);Universität Heidelberg, Zentrum für Astronomie (ZAH), Institut für Theoretische Astrophysik(海德堡大学天文学中心理论天体物理研究所);Universität Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen(海德堡大学跨学科科学计算中心);University of Padova(帕多瓦大学);INFN, Sezione di Padova(意大利国家核物理研究所帕多瓦分部)
Short-duration GRB 250221A Afterglow Driven by Two-Component Jets from the merger of a compact star
Guangxi University(广西大学);Nanjing University(南京大学);Purple Mountain Observatory, Chinese Academy of Sciences(中国科学院紫金山天文台);University of Science and Technology of China(中国科学技术大学)
GRB 250221A的后glow由双组分喷流模型解释,揭示了短持续时间GRB的双喷流机制及周际介质密度特征。
Discovery of 30 Repeating Fast Radio Burst Sources and Uniform Population Statistics of 80 Repeating Sources from CHIME/FRB
McGill University(麦吉尔大学);University of Amsterdam(阿姆斯特丹大学);California Institute of Technology(加州理工学院);Netherlands Institute for Radio Astronomy(荷兰射电天文研究所)
The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. VIII. A Comparison to Cosmological Short-duration Gamma-ray Bursts
Unveiling the spectral morphological division of fast radio bursts with CHIME/FRB Catalog 2
College of Sciences, Northeastern University(东北大学理学院);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院);College of Physics and Electronic Information Engineering, Guilin University of Technology(桂林理工大学物理与电子工程学院);College of Mathematics and Statistics, Liaoning University(辽宁大学数学与统计学院)
An Intertwined Short and Long GRB with 4-minute Separation
Ningbo University(宁波大学);Sapienza Universita di Roma(罗马智慧大学);ICRANet(国际相对论天体物理中心网络);The Hong Long Institute for Astronomy and Astrophysics, University of Hong Kong(香港大学香港天文与天体物理研究所);Department of Physics, University of Hong Kong(香港大学物理系);Purple Mountain Observatory, Chinese Academy of Sciences(中国科学院紫金山天文台);Department of Astronomy, University of Science and Technology of China(中国科学技术大学天文系);Max-Planck Institut für extraterrestrische Physik(马普地外物理研究所);Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology(广西相对论天体物理重点实验室物理科学与技术学院);Department of Physics, Bar-Ilan University(巴伊兰大学物理系);Division of Science, National Astronomical Observatory of Japan(日本国立天文台科学部);Department of Astronomy, Xiamen University(厦门大学天文系)
GRB 160425A包含两个间隔四分钟的子爆发,挑战了现有前身框架,要求重新评估GRB分类方案和前身场景。
A High Rate of White Dwarf-Neutron Star Mergers & Their Transients
我们认为,Badenes等人(2009年)最近突破性地发现了一颗附近(约50 pc)的白矮星-中子星(或黑洞)双星(SDSS 1257+5428),合并时间尺度约为5亿年,这意味着这样的系统很常见;我们估计银河系中有10^6个数量级。虽然存在很大的不确定性,但推导出的银河系合并速率名义上为每年约5 x 10^-4,仅比Ia型和核心坍缩超新星(SN)的速率分别小3-6倍和20-40倍。这意味着,在局部宇宙中,合并率约为0.5 ~ 1 x 10^4/Gpc ^3/年,比观测到的(未经过射束校正的)长持续时间伽马射线暴(GRB)率高出约5000-10000倍。我们估计,在95%的置信度下,银河系的死亡率下限为每年2.5 x 10^-5。我们简要讨论了这一发现对长、短持续时间伽玛暴及其前身星普查、Ib/c型超新星前身星的紧伴双星频率、超高能宇宙射线起源、快速旋转中子星和2-3 M太阳黑洞的形成、微弱类Ia超新星普查、以及用于即将到来的和当前的瞬态勘测(例如,LOSS、PTF、LSST),以及用于高频(LIGO)和低频(LISA)引力波搜索。
Short Spike, Long Story: Episode-Dependent Shifts of Long-Duration Type-I GRBs on $E_{\rm p,z}$--$E_{\rm iso}$ Plane
School of Astronomy and Space Science, Nanjing University(南京大学天文与空间科学学院);Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education(教育部现代天文学与天体物理重点实验室(南京大学));Yunnan Observatories, Chinese Academy of Sciences(中国科学院云南天文台);Center for Astronomical Mega-Science, Chinese Academy of Sciences(中国科学院天文大科学研究中心)