来自GRB 060614的新型马射线爆发分类方案
N Gehrels1, J P Norris, S D Barthelmy
1NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771, USA. gehrels@milkyway.gsfc.nasa.gov
Nature
|December 22, 2006
概括
一个附近的马射线爆发 (GRB) 挑战了现有的分类. 这个持续时间很长的事件缺乏超新星,这表明可能需要一个新的GRB类别.
科学领域:
- 天体物理学 天体物理学
- 宇宙爆炸,宇宙爆炸.
- 马射线天文学 马射线天文学
背景情况:
- 马射线爆发 (GRBs) 根据它们的发射持续时间被分为长时间和短时间类型,具有不同的起源和相关现象.
- 长时间的GRB通常与恒星形成区域的大规模恒星崩 (collapsars) 有关,并且经常伴随着超新星.
- 短时间的GRB与紧物体的合并有关 (中子星-中子星或中子星-黑洞) 在较不活跃的银河系区域,通常缺乏超新星.
研究的目的:
- 为了研究特殊的马射线爆发GRB 060614.4的性质.
- 为了确定GRB 060614是否符合已建立的长或短GRB分类.
- 探索GRB 060614的特性对当前GRB形成模型的影响.
主要方法:
- 对GRB 060614的持续时间,时间滞后和峰值亮度的分析.
- 深度光学观测以寻找伴随的超新星.
- 将GRB 060614的特征与已知长短GRB的特征进行比较.
主要成果:
- GRB 060614的持续时间约为102秒,与持续时间较长的GRB相吻合.
- 它的时间滞后和峰值亮度是短时间GRB的特征.
- 深度光学观测最终排除了伴随的超新星的存在.
结论:
- GRB 060614呈现出长时间和缺少超新星的独特组合,挑战了已有的GRB分类方案.
- 这些发现表明,目前对崩和紧物体合并的模型可能无法完全解释所有观察到的GRB现象.
- 这一事件需要对GRB的起源进行重新评估,并可能引入一个新的分类,将长短GRB结合起来.
更多相关视频
06:28Visualization of Low-Level Gamma Radiation Sources Using a Low-Cost, High-Sensitivity, Omnidirectional Compton Camera
Published on: January 30, 2020
05:18Radiation Planning Assistant - A Web-based Tool to Support High-quality Radiotherapy in Clinics with Limited Resources
Published on: October 6, 2023
相关概念视频
Detection of Black Holes
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Radiation: Applications
The average temperature of Earth is the subject of much current discussion. Earth is in radiative contact with both the Sun and dark space; it receives almost all its energy from the radiation of the Sun and reflects some of it into outer space. Dark space is very cold, about 3 K, so Earth radiates energy into it. For instance, heat transfer occurs from soil and grasses, the rate of which can be so rapid that frost can occur on clear summer evenings, even in warm latitudes.
The average...
The average...
Electromagnetic Waves
James Clerk Maxwell formulated a single theory combining all the electric and magnetic effects scientists knew during that time, calling the phenomena his theory predicted “Electromagnetic waves”. He brought together all the work that had been done by brilliant physicists such as Oersted, Coulomb, Gauss, and Faraday and added his own insights to develop the overarching theory of electromagnetism. Maxwell’s equations, combined with the Lorentz force law, encompass all the laws of electricity and...
Generating Electromagnetic Radiations
The German physicist Heinrich Hertz (1857–1894) was the first to generate and detect certain types of electromagnetic waves in the laboratory. Starting in 1887, he performed a series of experiments that confirmed the existence of electromagnetic waves and verified that they travel at the speed of light. Hertz used an alternating-current RLC (resistor-inductor-capacitor) circuit that resonated at a known frequency and connected it to a loop of wire. High voltages induced across the gap in the...
Plane Electromagnetic Waves I
The existence of combined electric and magnetic fields that propagate through space as electromagnetic (EM) waves is the most significant prediction of Maxwell's equations. As Maxwell's equations hold in free space, the predicted electromagnetic waves do not require a medium for their propagation. An EM wave comprises an electric field, defined as the force per charge on a stationary charge, and a magnetic field, which is the force per charge on a moving charge.
The EM field is assumed to be a...
The EM field is assumed to be a...
Plane Electromagnetic Waves II
Consider a plane wavefront traveling in position x-direction with a constant speed. This wavefront can be utilized to obtain the relationship between electric and magnetic fields with the help of Faraday's law.
