Chinese Astronomy and Astrophysics最新文献_第4页

Observations of Ion Cyclotron Waves Upstream from the Martian Bow Shock 火星弓形激波上游离子回旋波的观测

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.007

Li Jia-wei , Yang Lei , Wu De-jin , Dai Cun-li , Li Jian-ping , Xiang Liang , Luo Qing-yu , Cheng Zheng-wei

Ion cyclotron waves are widely present upstream from the Martian bow shock, with frequencies near the local proton cyclotron frequency in the spacecraft frame. The waves propagate quasi-parallel to the background magnetic field, and are associated with the solar wind picking up newly-ionized hydrogen from the Martian exosphere. In this work, a typical ion cyclotron wave event was observed by MAVEN (Mars Atmosphere and Volatile Evolution) probe upstream from the Martian bow shock. The further MVA (minimum variance analysis) results for this event show that the magnetic field perturbations are left-handed polarized and propagate quasi-parallel (the propagation angle

θ

= 12.37

^{\circ}

) to the background magnetic field. The relationship between the plasma perturbations and magnetic field perturbations is theoretically derived for slow magnetosonic, Alfv{'e}n, and fast magnetosonic waves based on the magnetohydrodynamic theory. If we take the wave propagation angle

θ

= 12.37

^{\circ}

estimated from the MVA method, the theoretically expected density perturbation and velocity perturbation along the background magnetic field are in serious disagreement with the MAVEN data. Through fitting the plasma density perturbation, velocity perturbation, and magnetic field perturbation, it is found that the ion cyclotron wave event can be explained by the superposition of oblique fast magnetosonic waves with a propagation angle of 63

^{\circ}

relative to the background magnetic field and parallel propagating Alfv{'e}n waves. The results are helpful to further understand the physical nature of the observed ion cyclotron wave-related perturbations upstream from the Martian bow shock, and have guiding implications for the re-modeling and numerical simulation of the plasma physical processes therein.

离子回旋波广泛存在于火星弓形激波的上游，其频率接近航天器框架内的本地质子回旋波频率。这些波与背景磁场近乎平行地传播，并且与太阳风从火星外逸层吸收新电离的氢有关。在这项工作中，MAVEN（火星大气与挥发物演化）探测器在火星弓形激波上游观测到一个典型的离子回旋波事件。对该事件进一步的最小方差分析结果表明，磁场扰动是左极化的，传播角θ = 12.37°)与背景磁场近似平行。基于磁流体动力学理论，推导了慢磁子、Alfv{'e}n和快磁子的等离子体扰动与磁场扰动之间的关系。如果取MVA法估算的波传播角θ = 12.37°，则理论上预期的密度摄动和速度摄动沿背景磁场方向的摄动与MAVEN数据严重不符。通过拟合等离子体密度摄动、速度摄动和磁场摄动，发现离子回旋波事件可以用相对于背景磁场传播角为63°的倾斜快速磁声波与平行传播的Alfv{'e}n波的叠加来解释。研究结果有助于进一步理解火星弓形激波上游观测到的离子回旋波相关扰动的物理性质，并对其中等离子体物理过程的重新建模和数值模拟具有指导意义。

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引用次数: 0

Multi-epochs Spectral Variability Analysis of Broad Absorption Lines in QSO SDSS J142225.03+535901.7 QSO SDSS J142225.03+535901.7中宽吸收谱线的多时期光谱变异性分析

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.003

He Dong-xu, He Zhi-cheng, Liu Gui-lin, Fang Wen-juan, Shen Lu, Zhu Dan-lei, Chen Ya-qi, Duan Bin

Broad absorption lines (BALs) in quasars are among the most compelling observational evidence for the presence of outflows. BALs commonly exhibit spectral variability, and analyzing such variations helps to constrain the physical models of these outflows. Variations in the ionizing continuum from the central engine of quasars are thought to be the primary mechanism driving most BAL variability. If the BAL absorption troughs in a quasar simultaneously vary (either weakening or strengthening) at different velocities in the same direction, it is highly likely that BAL variability is primarily induced by variations in the ionizing continuum. The quasar SDSS (Sloan Digital Sky Survey) J142225.03+535901.7, with 55 epochs of high signal-to-noise spectra, displays BAL variability. There is a significant anticorrelation (Spearman's correlation test, with a non-correlation probability

p

-value less than 0.05) between the equivalent widths of various velocity components of the BAL and the continuum luminosity. There is no significant anticorrelation between the equivalent widths of these components and the spectral index of the continuum, ruling out that the potential negative correlation between equivalent width and continuum luminosity is caused by the vertical motion of dusty gas along the line of sight. Therefore, it can be inferred that the BAL variability in this source is primarily driven by changes in the ionizing continuum.

类星体中的宽吸收谱线（baals）是证明物质外流存在的最有力的观测证据之一。bal通常表现出光谱变化，分析这种变化有助于限制这些流出的物理模型。来自类星体中心引擎的电离连续体的变化被认为是驱动大多数BAL变化的主要机制。如果类星体中的BAL吸收波谷在同一方向上以不同速度同时变化（减弱或增强），则极有可能BAL的变化主要是由电离连续体的变化引起的。类星体SDSS（斯隆数字巡天）J142225.03+535901.7具有55个高信噪谱期，显示出BAL变异性。BAL各速度分量的等效宽度与连续体亮度之间存在显著的反相关（Spearman’s相关检验，非相关概率p值小于0.05）。这些组分的等效宽度与连续体的光谱指数之间没有显著的反相关关系，排除了等效宽度与连续体光度之间潜在的负相关关系是由尘埃气体沿视线垂直运动引起的。因此，可以推断，该源BAL的变化主要是由电离连续体的变化驱动的。

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引用次数: 0

Observation Simulation and Orbital Retrieval of the CHES Satellite CHES卫星的观测模拟与轨道反演

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.001

Bao Chun-hui , Ji Jiang-hui , Tan Dong-jie , Jin Sheng , Huang Xiu-min , Wang Su , Chen Guo , Dong Yao , Liu Jia-cheng

So far, most of the exoplanets have been discovered with the radial velocity and transient methods. In comparison with these detection techniques, the astrometric method has unique advantages in the determination of planetary orbital parameters and masses. Closeby Habitable Exoplanet Survey (CHES) will search for terrestrial planets in the habitable zone around 100 sun-like stars in the solar system's neighbors (about 10 pc from the sun) using the micro-arcsecond space astrometry method, and further carry out a comprehensive census of nearby planetary systems to obtain the true mass of planets and three-dimensional orbital parameters to establish a complete database of the nearby planetary systems. Based on the observation mode and scientific objectives of the CHES satellite, this work conducted the simulated observations on Alpha Centauri A, a simulated solar system, 51 Peg, and the black hole Cyg X-1, and generated astrometric simulation data. Using two periodic spectra of Lomb-Scargle and BIC (Bayesian information criteria), the signal of the planetary orbit period is analyzed, and the orbit inversion of the planetary system is carried out with the Markov Chain Monte Carlo (MCMC) algorithm. In addition, this work further discusses the influence of the planets around the reference stars on the detection of habitable planets, and the BIC periodic spectrum can be used to identify the reference stars that may have planets around them.

迄今为止，大多数系外行星都是用径向速度和瞬态方法发现的。与这些探测技术相比，天体测量法在确定行星轨道参数和质量方面具有独特的优势。近地宜居系外行星调查（CHES）将利用微弧秒空间天体测量方法，在太阳系附近（距离太阳约10pc）的100颗类日恒星周围的宜居带内寻找类地行星，并进一步对近地行星系进行全面普查，获得行星的真实质量和三维轨道参数，建立完整的近地行星系数据库。根据CHES卫星的观测模式和科学目标，对半人马座阿尔法星A、模拟太阳系、51peg和黑洞Cyg X-1进行了模拟观测，生成了天体测量模拟数据。利用Lomb-Scargle和BIC（贝叶斯信息准则）两个周期谱对行星轨道周期信号进行了分析，并采用马尔可夫链蒙特卡罗（MCMC）算法对行星系统进行了轨道反演。此外，本工作还进一步讨论了参考恒星周围行星对可居住行星探测的影响，BIC周期谱可以用来识别可能有行星围绕的参考恒星。

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引用次数: 0

Large-scale CO Multi-line Observations of the S187 HII Region S187 HII地区大尺度CO多线观测

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.008

Xu Xiao-yun , Chen Xue-peng , Zhang Shi-yu , Sun Yan

The strong feedback of massive stars profoundly affects the interstellar medium around them, and may trigger the formation of next-generation stars. S187 is a massive star formation region located in the second quadrant of the Milky Way, showing a “Collect and Collapse” triggered star formation pattern. Based on the

^{12} CO

/

^{13} CO

/

C^{18} O

(J=1-0, following J=1-0 is omitted for simplicity) spectra line data from the Milky Way Imaging Scroll Painting (MWISP) survey, the basic properties of the molecular cloud in the S187 region were studied, and the feedback of massive stars to molecular cloud was explored. Using GaussPy+ and clustering algorithm, 32 clouds were identified in this region, and the distances of eight of them were measured by combining the star extinction data of Gaia (Global Astrometric Interferometer for Astrophysics) satellite. The relatively dense gas content traced by

^{13} CO

and

C^{18} O

in S187 region is 1-2 orders of magnitude higher than that of molecular clouds in most regions of the second quadrant of the galactic plane. In the S187 region, 243

^{13} CO

and 98

C^{18} O

clumps were identified, among which 7

^{13} CO

and 5

C^{18} O

clumps had the potential to form massive stars. The results show that the feedback of massive stars has an obvious effect on the aggregation of molecular cloud around them, which provides conditions for the formation of the next-generation of massive stars.

大质量恒星的强烈反馈深刻地影响着它们周围的星际介质，并可能引发下一代恒星的形成。S187是一个位于银河系第二象限的大质量恒星形成区，呈现出“聚集和坍缩”触发的恒星形成模式。基于MWISP （Milky Way Imaging Scroll Painting）巡天12CO/13CO/C18O （J=1-0，下面省略J=1-0）谱线数据，研究了S187区域分子云的基本性质，并探讨了大质量恒星对分子云的反馈。利用GaussPy+和聚类算法在该区域识别出32个云，并结合Gaia （Global Astrometric Interferometer for Astrophysics）卫星的恒星消光数据测量了其中8个云的距离。S187区域13CO和C18O测得的相对致密气体含量比银道第二象限大部分区域的分子云高1-2个数量级。在S187区域，共鉴定出243个13CO和98个C18O团块，其中7个13CO和5个C18O团块具有形成大质量恒星的潜力。结果表明，大质量恒星的反馈对其周围分子云的聚集有明显的影响，为下一代大质量恒星的形成提供了条件。

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引用次数: 0

The Corrections of Sub-picosecond Propagation Time Delays and the Allan Variance of Discontinuous Measurement for the Inter-satellite Time Transfer 星间时间传输中亚皮秒传播时延的修正和不连续测量的Allan方差

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.004

He Ke-liang, He Yu-ling, Wang Guo-yong

The asymmetric signal propagation paths between two satellites lead to the unequal time delays at receiving signal time, which should be accurately corrected when solving the clock difference of inter-satellite time transfer. The observation method of clock difference is analysed, the asymmetric signal propagation time delay caused by satellite motion is then derived and reduced, the delay caused by relativistic deflection of light is also calculated using the time transfer function method, and the residual error stability of the propagation time delay correction is evaluated, which improve the correction accuracy of asymmetric signal propagation time delay to 0.1 ps under the current condition of orbit determination. The autocorrelation function representation of Allan variance is extended, and a method of computing the Allan variance error with missing measuring data is proposed based on the statistical method. The effect of missing measuring data on frequency stability calculation of different noises is also analysed. Overall, a systematic correction approach of the propagation time delay and Allan variance with discontinuous measurement for the inter-satellite two-way time transfer has been constructed, which can be used in the clock difference correction of inter-satellite time transfer in the order of ps.

由于两颗卫星之间的信号传播路径不对称，导致接收信号时的时延不相等，在解决星间时间传输的时钟差时，需要对其进行精确校正。分析了时钟差的观测方法，推导并减小了卫星运动引起的非对称信号传播时延，利用时间传递函数法计算了光的相对论性偏转引起的时延，并评价了传播时延校正的残差稳定性。在当前定轨条件下，将非对称信号传播时延的校正精度提高到0.1 ps。扩展了Allan方差的自相关函数表示，提出了一种基于统计方法的测量数据缺失情况下Allan方差误差的计算方法。分析了测量数据缺失对不同噪声下频率稳定度计算的影响。总体而言，构建了星间双向时间传递的不连续测量传播时延和Allan方差的系统校正方法，可用于星间时间传递的ps级时钟差校正。

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引用次数: 0

Wulong: A New Main Group Pallasite 武隆：一个新的主群Pallasite

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.006

Liu Hang-cheng , Zhang Xin-ru , He Wen-zhong , Liao Shi-yong , Hsu Wei-biao , Jiang Yun

As the fragments of differentiated asteroids in the early solar system, pallasites record deep-mantle and core processes. As such, studying the origin of pallasites could help us understand the formation and differentiation processes governing the evolution of planets. Wulong pallasite was found in Inner Mongolia, China around 1992, but didn't get much attention until 2020. In this study, we reported the detailed petrography and mineralogy, oxygen isotopic composition, and metal phase chemistry of Wulong pallasite. Wulong pallasite is mainly composed of olivine (

\sim

72.7 vol.%), Fe-Ni metal (

\sim

26.2 vol.%), troilite (

\sim

0.6 vol.%), schreibersite (

\sim

0.4 vol.%), and chromite (

\sim

0.1 vol.%) etc. Olivine (Fa

_{12.5 \pm 0.2}

) and chromite (Al

#

\sim

15.2

\pm

0.9, Fe

#

\sim

67.9

\pm

1.5) compositions are homogeneous, and no chemical zoning is observed. Siderophile element contents of a metal phase are Ni, 7.71 wt.%; Ga, 17.8

μ

g/g; and Ge, 26.2

μ

g/g. The mean

δ

^{18}

O value is 3.04

\pm

0.01‰,

Δ

^{17}

O value is

-

0.18

\pm

0.01‰. In terms of the Fa value of olivine, metal phase chemistry, and oxygen isotope ratios, Wulong could be a new member of main group pallasite.

作为太阳系早期分化小行星的碎片，pallasites记录了深部地幔和岩心过程。因此，研究pallasites的起源可以帮助我们理解控制行星演化的形成和分化过程。武隆pallasite是1992年左右在中国内蒙古发现的，但直到2020年才引起人们的关注。本文详细报道了武隆pallasite的岩相学、矿物学、氧同位素组成和金属相化学。武隆pallasite主要由橄榄石（~ 72.7 vol.%）、Fe-Ni金属（~ 26.2 vol.%）、三硅石（~ 0.6 vol.%）、schreiberite （~ 0.4 vol.%）、铬铁矿（~ 0.1 vol.%）等组成。橄榄石（Fa12.5±0.2）和铬铁矿（Al# ~ 15.2±0.9,Fe# ~ 67.9±1.5）组成均匀，无化学分带。金属相的亲铁元素含量为Ni， 7.71 wt.%；Ga, 17.8 μg/g；Ge为26.2 μg/g。平均δ18O值为3.04±0.01‰，Δ17O值为−0.18±0.01‰。从橄榄石Fa值、金属相化学、氧同位素比值等方面分析，武隆可能是主群pallasite的新成员。

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引用次数: 0

A Study of Pulse Nulling in PSR J1701 – 3726 PSR J1701 - 3726中脉冲零化的研究

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.002

Cai Yan-qing , Li Qing-ying , Tian Jie , Li Wei , Dang Shi-jun , Shang Lun-hua , Xu Xin , Zhi Qi-jun , Wu Jia-chao

Using the observation data of Parkes 64 m radio telescope at a central frequency of 1369 MHz, the pulse nulling phenomenon of PSR J1701–3726 was analyzed. It is found that the pulse nulling phenomenon of this pulsar has quasi-periodic, and the quasi-period value approximately is 81.25

P

, where

P

is the rotation period, and the pulse nulling ratio NF (Nulling Fraction) is calculated to be 27%

\pm

0.97%. Further study on the change of relative energy in the on-pulse region over time shows that there are four different switching modes a, b, c, and d between null state and burst state, among which mode a occurs 23 times, mode b occurs 6 times, mode c occurs 5 times, and mode d occurs 79 times, indicating that there may be some randomness in state transitions.

利用Parkes 64 m射电望远镜1369 MHz中心频率的观测数据，分析了PSR J1701-3726的脉冲零化现象。发现该脉冲星的脉冲零化现象具有准周期性，其准周期值约为81.25P，其中P为其自转周期，计算出脉冲零化比NF （nulling Fraction）为27%±0.97%。进一步研究脉冲导通区相对能量随时间的变化，发现零态与爆发态之间存在a、b、c、d四种不同的切换模式，其中模式a出现23次，模式b出现6次，模式c出现5次，模式d出现79次，说明状态转换可能存在一定的随机性。

引用次数: 0

Research on Starlink Ephemeris Published by SpaceX SpaceX发布的星链星历研究

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.005

Liu Ai-rong , Xiong Yong-qing , Hui Jian-jiang , Xu Xiao-li , Gong Jun

Faced with the significant disruption of normal space activities caused by Starlink satellites, the Starlink ephemeris published by SpaceX provides an opportunity for relevant research on Starlink satellites. However, due to the lack of clear instructions, it is challenging to utilize the data further. Analysis of the ephemeris file reveals that it primarily represents the predicted orbit for the next 3 d. Research on mean orbital elements indicates that the front part of the ephemeris is an extrapolated orbit with perturbations up to at least the 20th order of Earth's gravitational field, while the latter part is a design orbit with

J_{2}

perturbation. The ephemeris includes covariance information, providing accuracy details. The covariance indicates that the accuracy of the ephemeris for satellites located in parking and working orbits is better than 2 km in the first day, while the accuracy of satellites in raising orbit increases rapidly to thousands of meters in less than half a day. Utilizing the designed orbit of the ephemeris enables a more accurate analysis of constellation configuration, especially the designated position of each satellite, thus facilitating the identification and tracking of Starlink satellites. The study provides valuable insights for the extensive application of Starlink ephemeris, serving as a beneficial reference for maneuver detection and collision warnings of Starlink satellites.

面对星链卫星对正常空间活动造成的重大干扰，SpaceX发布的星链星历表为星链卫星的相关研究提供了契机。然而，由于缺乏明确的指示，进一步利用这些数据是具有挑战性的。对星历文件的分析表明，它主要代表了未来3 d的预测轨道。对平均轨道元的研究表明，星历文件的前半部分是一个外推轨道，其扰动至少达到地球引力场的20阶，而后半部分是一个设计轨道，其扰动至少达到地球引力场的20阶。星历表包含协方差信息，提供精度细节。协方差分析表明，静止轨道和工作轨道卫星的星历表精度在第一天优于2 km，而上升轨道卫星的星历表精度在不到半天的时间内迅速提高到数千米。利用星历表的设计轨道，可以更准确地分析星座结构，特别是每颗卫星的指定位置，从而便于星链卫星的识别和跟踪。该研究为星链星历的广泛应用提供了有价值的见解，为星链卫星的机动探测和碰撞预警提供了有益的参考。

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引用次数: 0

Reducing the Measuring Error of Solar Magnetic Field by Stereo Observation 利用立体观测减小太阳磁场测量误差

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.010

Zeng Bai-yu , Guo Yang , Li Chuan , Li Zhen , You Wei , Huang Fan , Zhang Lan-qiang , Yang Jin-sheng

Observing the solar magnetic field from a single point, we can measure the magnetic field component along the line of sight and the magnetic field component perpendicular to the line of sight (transverse field). However, the accuracy of transverse field is one order of magnitude lower than that of the radial field, and there is a

180^{\circ}

uncertainty in the direction of the transverse magnetic field. The goal of this paper is to improve the accuracy of the transverse field of the solar magnetic field. It is considered to observe the magnetic field at the Sun-Earth L5 point and Earth simultaneously, and the error reduction can be obtained through model construction and data analysis. The specific methods are as follows. Coordinate relations of magnetic fields at Earth and L5 point are obtained by spherical trigonometry formula, and the corrected errors of the transverse magnetic field at L1 points are obtained by error propagation formula. Then, we calculate the error distribution of the solar magnetic field data, and simulate two data conforming to the solar magnetic field distribution, which are respectively used as the error diagram of Earth and L5 point. Finally, by combining the data of Earth and L5 point, the corrected data whose transverse field error at Earth has been reduced, are obtained and compared with the original transverse field data. It is found that the transverse field error of Earth can be reduced to about 17% of the original.

从单点观测太阳磁场，可以测量沿视线方向的磁场分量和垂直于视线方向的磁场分量（横场）。但是，横向磁场的精度比径向磁场低一个数量级，而且横向磁场的方向有180°的不确定性。本文的目标是提高太阳磁场横向场的精度。考虑在日地L5点和地球同时观测磁场，通过模型构建和数据分析来减小误差。具体方法如下：利用球面三角公式求得地球与L5点磁场的坐标关系，利用误差传播公式求得L1点横向磁场的修正误差。然后，我们计算了太阳磁场数据的误差分布，并模拟了两个符合太阳磁场分布的数据，分别作为地球和L5点的误差图。最后，结合地球和L5点的数据，得到了减小了地球横向场误差的校正数据，并与原始横向场数据进行了比较。结果表明，地球的横向场误差可以减小到原来的17%左右。

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引用次数: 0

Advance in the Research of Stellar Superflares 恒星超级耀斑研究进展

Q4 Physics and Astronomy

Chinese Astronomy and Astrophysics

Pub Date : 2025-01-01 DOI: 10.1016/j.chinastron.2025.03.009

Yong Hao-ran , Lin Jun

The Solar flare is one of the most violent eruptive phenomena in the Solar system, which releases energy up to

10^{25}

J in tens of minutes. With the development of observational techniques, similar flare events have been observed on stars, with typical energy of 10 to

10^{4}

times that of Solar flares, which is known as the superflare. Studies of stellar superflares and their mechanisms are not only important for understanding the internal structure, evolution, and magnetic activities of stars, but also for exploring the habitability and extraterrestrial life on exoplanets. A brief introduction is first given on Solar flares and the associated phenomena of magnetic activities, stellar magnetic field, and superflares of stars. Then, current detection methods and research results of stellar superflares are reviewed in terms of selection, energy evaluation, starspots, and the statistical relationships between the flare parameters and stellar parameters. Meanwhile, a comparison is made with the theories of Solar flares and the related physical processes to explore their similarities and connections. Finally, a summary is made and the related further work is also discussed.

太阳耀斑是太阳系中最剧烈的爆发现象之一，它在数十分钟内释放出高达 1025 焦耳的能量。随着观测技术的发展，在恒星上也观测到了类似的耀斑事件，其典型能量是太阳耀斑的 10 到 104 倍，这就是所谓的超级耀斑。对恒星超级耀斑及其机制的研究不仅对了解恒星的内部结构、演化和磁活动非常重要，而且对探索系外行星的宜居性和系外生命也非常重要。本文首先简要介绍了太阳耀斑及其相关的磁活动现象、恒星磁场和恒星超级耀斑。然后，从耀斑的选择、能量评估、星斑以及耀斑参数与恒星参数之间的统计关系等方面回顾了目前恒星超级耀斑的探测方法和研究成果。同时，将其与太阳耀斑理论及相关物理过程进行比较，探讨两者的相似性和联系。最后，进行了总结并讨论了相关的进一步工作。

{"title":"Advance in the Research of Stellar Superflares","authors":"Yong Hao-ran , Lin Jun","doi":"10.1016/j.chinastron.2025.03.009","DOIUrl":"10.1016/j.chinastron.2025.03.009","url":null,"abstract":"<div><div>The Solar flare is one of the most violent eruptive phenomena in the Solar system, which releases energy up to <span><math><msup><mn>10</mn><mn>25</mn></msup></math></span> J in tens of minutes. With the development of observational techniques, similar flare events have been observed on stars, with typical energy of 10 to <span><math><msup><mn>10</mn><mn>4</mn></msup></math></span> times that of Solar flares, which is known as the superflare. Studies of stellar superflares and their mechanisms are not only important for understanding the internal structure, evolution, and magnetic activities of stars, but also for exploring the habitability and extraterrestrial life on exoplanets. A brief introduction is first given on Solar flares and the associated phenomena of magnetic activities, stellar magnetic field, and superflares of stars. Then, current detection methods and research results of stellar superflares are reviewed in terms of selection, energy evaluation, starspots, and the statistical relationships between the flare parameters and stellar parameters. Meanwhile, a comparison is made with the theories of Solar flares and the related physical processes to explore their similarities and connections. Finally, a summary is made and the related further work is also discussed.</div></div>","PeriodicalId":35730,"journal":{"name":"Chinese Astronomy and Astrophysics","volume":"49 1","pages":"Pages 17-80"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143627929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0