边缘耀斑中HeI 10830的加宽计算

讨论了 ＨｅＩ １０８３０Ａ的 Ｄｏｐｐｌｅｒ和 Ｓｔａｒｋ加宽机制以及各种加宽参数的计算，并 得到以下一些结论：辐射阻尼对 ＨｅＩ １０８３０ Ａ的加宽作用与 Ｄｏｐｐｌｅｒ效应相比可以忽略； 在公认的耀斑电子密度（Ｎｅ＝３．２ ×１０１３ｃｍ－３）的情况下，所有阻尼项均不可能产生可以 觉察的加宽；直到 Ｎｅ＝１０１５ｃｍ－３，各种阻尼对线心半宽的增加都不起作用，其值最多 在１０－３的量级，因此；线心都可以看作是Ｄｏｐｐｌｅｒ加宽；当 Ｎｅ＞１０１４ ｃｍ－３时，Ｓｔａｒｋ 加宽，特别是电子碰撞的 Ｓｔａｒｋ加宽将在 ＨｅＩ １０８３０ Ａ的加宽中起主要作用；如要 Ｓｔａｒｋ 加宽谱线的线翼比纯Ｄｏｐｐｌｅｒ加宽大１－２倍，则阻尼加宽半宽与。可以相比拟；如果 用 Ｓｔａｒｋ加宽来解释 １９８９年边缘耀斑的观测轮廓，则电子密度将达１０～（１７）ｃｍ－３，与氦 原子的碰撞阻尼（γ３）造成的加宽对Ｉ１２和Ｉ３两分量明显不同，它们对Ｉ１２的影响比对Ｉ３ 的影响大近一个量级，我们的观测显示Ｉ１２和Ｉ３线翼的延伸基本一样，因而我们的观测 轮廓不可能是γ３造成的     

The role of non-thermal electrons in the hydrogen and calcium lines of stellar flares

There is observational evidence showing that stellar and solar flares occur with a similar circumstance, although the former are usually much more energetic. It is expected that the bombardment by high-energy electrons is one of the chief heating processes of the flaring atmosphere. In this paper we study how a precipitating electron beam can influence the line profiles of Ly α , H α , Ca  ii K and λ 8542. We use a model atmosphere of a dMe star and make non-LTE computations taking into account the non-thermal collisional rates owing to the electron beam. The results show that the four lines can be enhanced to different extents. The relative enhancement increases with increasing formation height of the lines. Varying the energy flux of the electron beam has different effects on the four lines. The wings of Ly α and H α become increasingly broad with the beam flux; change of the Ca  ii K and λ 8542 lines, however, is most significant in the line centre. Varying the electron energy (i.e. the low-energy cut-off for a power-law beam) has a great influence on the Ly α line, but little on the H α and Ca  ii lines. An electron beam of higher energy precipitates deeper, thus producing less enhancement of the Ly α line. The Ly α /H α flux ratio is thus sensitive to the electron energy.     

磁场重联和日冕物质抛射

Basic processes of magnetic reconnection and observations of coronal mass ejection are introduced. A possible mechanism of CME caused by magnetic rcconnection in the current sheet of solar corona is suggested.     

AR5395及AR6659的贮能释能周期性

本文分析了了AR5395和AR6659的X射线耀斑活动周期性，耀斑强度周期的存在表明活动区的能量积累和释放过程具有可重复性，包括贮存的能量大小也具可重复性，计算得出AR5395的耀风强度周期为24．49小时，而AR6659的周期为57．39小时，耀斑指数按周期的分布证明在一个贮能周期中活动区贮存的能量大致相同，周期内的平均耀斑指数代表能量积累效率，AR6659较之AR5395有较长的能量积累周期和较高的能量积累效率．此外，本文还讨论了耀斑事件出现的周期．这种周期的长短代表活动区磁结构对于耀斑出现的稳定程度，并且，当活动区处于较高能量状态（即相对势场状态的偏离较大）时，出现耀斑不稳定性的可能性增加。     

Detection of transient high frequency optical oscillations of the flare star YZ CMin

In this paper we present the results of the analysis of the B ‐light curve for the flares of the red dwarf YZ CMin (dM4.5e), which were observed on February of 2002, with the help of the 30‐inch Cassegrain telescope of the Stephanion Observatory, Greece. Discrete Fourier Transform analysis and the use of the Brownian Walk noise enable us to estimate the proper random noise and detect possible weak transient optical oscillations. Our results indicate that: (1) Transient high frequency oscillations occur during the flare event and during the quiet‐star phase as well. (2) The observed frequencies range between 0.0083 Hz (period 2 min) and 0.3 Hz (period 3 s) is not rigorously bounded. The phenomenon is most pronounced during the flare state. (3) During the flare state: (a) Oscillations with period 2 to 1.5 min, 60 s, 11 s, 7.5 s, and 4 s appear around the maximum light state and persist during the whole flare state, (b) from the flare maximum phase on, a progressive increase of oscillations with periods 30 s, 20 s down to 4.0 s is markedly indicated, and (c) at the end of the flare only the oscillation of the pre‐flare state do remain. Our observations are consistent with the phenomenology of impulsively exited oscillations on a coronal magnetic loop and subsequent chromospheric heating by electronic flux at the foot of the loop or/and by soft X‐ray coronal emission. Our observation give evidence that more than one impulsive events may occur in the course of an observed flare (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

利用GPS研究南极电离层TEC对太阳耀斑的异常响应

利用了南极地区IGS站和中山站GPS观测数据,计算了太阳耀斑期间的电离层TEC,分析了南极电离层TEC对太阳耀斑的异常响应。     

BD＋47819：一颗A5型特殊耀星

本文作者在对αＰｅｒ疏散星团的观测工作中发现了一颗罕见的早型亮耀星，从对其光谱观测的结果，可以确定它为－Ａ５型星．这与传统恒星耀发理论是相悖的。