一个磁星驱动的X射线瞬态,是二进制中子星合并的后果
Y Q Xue1,2, X C Zheng3,4,5, Y Li6
1CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei, China. xuey@ustc.edu.cn.
Nature
|April 12, 2019
概括
研究人员发现了第二个X射线瞬态,CDF-S XT2,可能由中子星合并形成的毫秒磁星提供动力. 这一发现加强了这些宇宙事件与X射线瞬态之间的联系, 即使没有短暂的马射线爆发.
科学领域:
- 天体物理学与天文学
- 高能天体物理学
- 引力波天文学
背景情况:
- 中子星的合并与短马射线爆发 (GRB) 有关.
- 合并可能会产生磁星,在一些GRB之后观察到的X射线高原.
- 短时间GRB的X射线短暂可能会独立于短时间GRB.
研究的目的:
- 调查可能来自双中子恒星合并的X射线短暂物质的性质.
- 分析新发现的X射线瞬态CDF-S XT2的特性.
- 评估CDF-S XT2与中子星合并事件的相关性.
主要方法:
- 对X射线短暂CDF-S XT2的观察和分析.
- 对CDF-S XT2的主星系的红移测量 (z = 0.738).
- 将CDF-S XT2的光曲线和空间分布与理论模型和已知的天体物理事件进行比较.
主要成果:
- CDF-S XT2的光线曲线与一个毫秒磁力相一致.
- CDF-S XT2位于其恒星形成的主星系的外围,类似于短GRB祖先位置.
- 这种短暂事件的估计发生率与从引力波检测中推断出的双中子恒星合并率一致.
结论:
- CDF-S XT2提供了强有力的证据,
- 这些事件可以发生在没有相关的短马射线爆发的情况下,扩大我们对融合电磁对应物的理解.
- 这些发现支持二进制中子星的合并是观察到的X射线瞬态的重要来源.
相关概念视频
Nuclear Power
9.4K
Controlled nuclear fission reactions are used to generate electricity. Any nuclear reactor that produces power via the fission of uranium or plutonium by bombardment with neutrons has six components: nuclear fuel consisting of fissionable material, a nuclear moderator, a neutron source, control rods, reactor coolant, and a shield and containment system.
Nuclear Fuels
Nuclear fuel consists of a fissile isotope, such as uranium-235, which must be present in sufficient quantity to provide a...
Nuclear Fuels
Nuclear fuel consists of a fissile isotope, such as uranium-235, which must be present in sufficient quantity to provide a...
9.4K
Binary Fission
2.6K
Binary fission is the primary mode of asexual reproduction in prokaryotes, such as bacteria. It results in the production of two genetically identical daughter cells. This highly efficient process ensures the rapid propagation of bacterial populations under favorable conditions and involves coordinated cellular and molecular events.DNA Replication and SeparationThe process begins with the replication of the bacterial chromosome. The circular DNA molecule unwinds at a specific origin of...
2.6K
Binary Fission
63.0K
Fission is the division of a single entity into two or more parts, which regenerate into separate entities that resemble the original. Organisms in the Archaea and Bacteria domains reproduce using binary fission, in which a parent cell splits into two parts that can each grow to the size of the original parent cell. This asexual method of reproduction produces cells that are all genetically identical.
63.0K
X-ray Crystallography
25.9K
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
25.9K
Power
12.9K
The concept of work involves force and displacement; meanwhile, the work-energy theorem relates the net work done on a body to the difference in its kinetic energy, calculated between two points on its trajectory. While none of these quantities or relations involves time explicitly, we know that the time available to accomplish work is often just as important as the amount of work itself. For example, sprinters in a race may have achieved the same velocity at the finish, therefore,...
12.9K
Series R—L Circuit Transients
386
In a series resistor-inductor (R-L) circuit, closing the switch at the start of the time period simulates a three-phase short circuit, a fault condition where all three phases of an unloaded synchronous machine are short-circuited. When there is no fault impedance and no initial current, the initial voltage is determined by the phase angle of the source voltage.
Using Kirchhoff's Voltage Law (KVL) to analyze this circuit helps determine the total asymmetrical fault current, which consists...
Using Kirchhoff's Voltage Law (KVL) to analyze this circuit helps determine the total asymmetrical fault current, which consists...
386


