SN1987A晚期X射线辐射的分析

在中央中子星吸积模型较好的解释了超新星ＳＮ１９８７Ａ晚期光度演化的基础上,本提出了ＳＮ１９８７Ａ晚期Ｘ射线辐射的一种新的解释。利用模型计算邮的吸积光度以及ＳＮ１９８７Ａ膨胀气体包层的化学组分及分布,计算了出射的软Ｘ射线（０．５－２ｋｅＶ）光度的演化,并与观测作了比较,我们认为ＳＮ１９８７Ａ晚期由中央中子星吸积产生的软Ｘ射线光度经过一段时间的增长后,将在４１００天左右开始下降。     

六年来超新星SN1987A的研究

本文阐述了超新星ＳＮ１９８７Ａ爆发六年多来的研究进展情况，分三个方面介绍，首先介绍关于热光变曲线演化的研究情况，其次，介绍超新星 ＳＮ１９８７Ａ的光谱形成及其演化（重点介绍星云相期间）。最后，讨论Ｘ射线和γ射线的辐射，并展望以后的研究方向。     

吸积对超新星SN1987A的热光度贡献的再探讨

超新生ＳＮ１９８７Ａ中央可能存在的致密天体（如中子星）,通过吸积那些超新星爆发时抛射速度小于逃逸速度的物质而产生的吸积光度,对ＳＮ１９８７Ａ晚期的热光度演化吸重要的贡献。本改进了以前的理论模型,给出更为合理的定理计算,对所提出的特殊的呼积机制作了仔细分析,特别强调,这种吸积是膨胀包层中的物质由于引力作用引起的长时期内的连续回落,它有别于其它的吸积模型,并给出直接的观测证据,假设致密天体是１．４Ｍ     

吸积对超新星SN 1987A的热光度贡献的再探讨

超新星ＳＮ１９８７Ａ中央可能存在的致密天体（如中子星）,通过吸积那些超新星爆发时抛射速度小于逃逸速度的物质而产生的吸积光度,对ＳＮ１９８７Ａ晚期的热光度演化有重要的贡献．本文改进了以前的理论模型,给出了更为合理的定量计算,对所提出的特殊的吸积机制作出了仔细分析,特别强调,这种吸积是膨胀包层中的物质由于引力作用引起的长时期内的连续回落,它有别于其它的吸积模型,并给出直接的观测证据．假设致密天体是１４Ｍ⊙,半径为１０６ｃｍ的中子星,我们的计算表明,它的吸积能提供足够的能量来形成ＳＮ１９８７Ａ热光度曲线在１０５０天左右时的鼓包,并且使热光度曲线从８００天以后下降变缓     

超新星SN 1987A的热光度演化──内部中子星的贡献

本文介绍了超新星SN1987A爆发六年多来其热光度演化的研究情况．爆发后的前800天，观测的热光度曲线与由超新星爆发时合成的放射性元素的放射衰变加热模型符合得很好．但900天以后，观测的热光度曲线比考虑了所有放射性元素贡献后的理论曲线下降得还要缓慢．这可能表明有新的能源在起作用．我们认为这个新的能源可能是超新星爆发时产生的中子星的吸积．通过吸积超新星爆发时抛射气壳中小于逃逸速度的部分物质而增大SN1987A的热光度．这一模型能很好地解释900天以后的光度曲线的下降变级以及900至1200天之间光度曲线的凸起，这也为内部中子星的存在提供了间接的证据．     

关于SN1987A之光子与中微子旅程时间基本相同的解释

本文对SN1987A之光子及中微子旅程时间基本相同的事实作了较全面和深入的分析,与一些文献的解释不同,给出了两种可能的新解释,其中一种解释意味着时空有挠和具有绝对平行性。     

dMe耀星的X射线的辐射

From Einstein Observatory, we know most nearby dM flare stars have X-ray emissions. X-ray flare energy of dM stars is far larger than that of large flares of sun. The corona temperature of dM stars is higher than that of sun. The X-ray flare time scales are several minutes to hours. Star corona heating model for X-ray flares is loop model, which provide a mechanism to convert magnetic energy to heat energy in star corona.Within identification of ROSAT X-ray sources, we found that X-ray source: RX1102.0 4347 corresponds to WX UMa, a dM5e flare star, which is in a nearby visual binary: Gliese 412A B. The binary is very near to earth, 5.38pc, and has high proper motion, 4".54/ year. The binary is also an Einstein X-ray source: 1 E1103.0 4346.In March 27, 1993, we observed WX UMa by CCD BVRI photometry at BAO 2.16m telescope. Magnitudes of the star are: V = 14.56, B-V = 1.95, V-R = 0.97, R-I = 2.06, which are similar to previous observations.From the ROSAT X-ray survey data in November 7-17, 1990, average X     

致密星的X射线辐射时延现象

能谱仅反映了高能天体辐射的部分性质，而高能X射线辐射的时变可以反映致密天体的动态性质。因此，在构造高能辐射的理论模型时，既要考虑X辐射的能谱性质，也要考虑其时变性质。特别对高能天体X辐射的快速光变，一般认为其发生在致密天体附近，致密天体快速光变的研究可以揭示出致密天体附近的物理性质，因此，时变可以对X辐射模型给以很强的限制。X射线源不同能量光子到达观测者的时间差称为X射线辐射的时延。介绍了高能X辐射时变中的时延分析方法及其最新发展，综述了致密双星系统中黑洞侯选林和中子星的时延现象，并简单介绍了为解释这些现象所发展的模型，以及时延对模型的限制。     

Temperature evolution of the envelope of SN 1987A

We present a theoretical derivation of the H_α line luminosity of the expanding envelope of SN 1987A from the theory of hydrogen recombination lines. A remarkable deviation of our calculated H_α light curve from the observed light curve was found when a constant temperature was assumed. From the deviation we easily derive the temperature evolution. The temperature actually rises after day 500 and this may be explained as follows: as the shell expands, the electron and ion densities rapidly fall, greatly reducing the recombination cooling rate, while heating continues.     

The 23 year reminiscence of the SN1987A

Twenty three years ago on February 23, 1987, the explosion of the SN in the L.M.C. was observed both optically and by underground detectors. The optical observations were done in Chile and Australian observatories while the neutrino burst was detected by several underground experiments in the Northern Hemisphere, running at that time: Mt. Blanc in Italy, Kamioka in Japan, and Baksan in Russia and IMB in the USA. For the first time in the history of human existence, an astrophysical phenomenon has been observed in underground detectors. In this astrophysical event, the Mt. Blanc experiment detected five pulses on-line that were not at the same time, as detected by the other three detectors around five hours later. It is still not clear to astrophysicists why two bursts at two different times have been detected and how an SN can generate two neutrino bursts. After 23 years a model has proposed an explanation for a double stage collapse at two different times, as recently suggested by V.S. Imshennik and O. Ryazhskaya. In this paper, a detailed occurrence of something strange that happened on February 23rd is presented while most of the scientific information has been exhibited in other published papers.     

What type was SN 1987A?

A comparison is made of the light and colour curves of the SN 1987A in the first 280 days with the mean properties of type II supernovae. The conclusion is that even though it has H lines, and was not a typical type II supernova, but a peculiar object from a photometric point of view. The implications for inclusion of SN 1987A in the context of the usual Minkowski-Zwicky classification are explicitly discussed.     

Iron whiskers in supernova SN 1987A

The far-infrared flux measurements for supernova SN 1987A are modelled in terms of length distributions of iron whiskers. The excess emission detected at 1.3µm can be explained on the basis of such a model.     

A possible explanation of the second neutrino burst from SN 1987A

It is argued that the neutrino bursts registered on February 23.316 UT, 1987 signalized the transition of a fresh-borne neutron star into a superdense state. The neutron star is supposed to be formed approximately five hours before at February 23.12 UT in the supernova SN 1987a in the Large Magellanic Cloud.     

Passive and active seti strategies using the synchronization of SN1987A

A passive and active strategy for the reception and transmission of call signals, from and to other possible extraterrestrial civilizations is suggested using the explosion of SN1987A. The reception area is an ellipsoid with the Earth and the supernova in its focuses, in the direction of SN1987A. Three hundred and forty objects have been identified inside this surface and four of them are stars with environments similar to our sun (e.g. necessary for the development of life and intelligence). A search strategy to look for fake pulsars signals, originated in other possible technological civilizations, in this direction, is examined.The active strategy consist in the transmission of terrestrial signals towards the hyperboloid surface (with the same focuses) in the antipodal direction of the supernova explosion. Thirty-three objects have been identified inside the hyperboloid and three of them are solar-type nearby stars. The transmission characteristics of a terrestrial origin fake pulsar (e.g. modulation, frequency, bandwidth, periods, duty cycle, etc.) are discussed in some detail. The possible use of available planetary radars to develop such proposal and the criterion of artificiality, without any implicit code or semantics is reviewed. A difference between active search and communication is established.Presented at the 2nd UN/ESA Workshop, held in Bogotá, Colombia, 9–13 November, 1992.     

超新星SN1987A包层的温度演化

本文介绍了超新星ＳＮ１９８７Ａ爆发六年来关于其包层温度演化的研究情况。温度是研究超新星的各种物理过程的一个基本参量，然而目前对温度的各种估算十分弥散，结果相当不确定。本文利用辐射转移理论的逃逸几率方法，导出Ｈａ线辐射理论光变曲线，通过与观测曲线的比较，可定量地导出超新气壳的温度演化行为。这一模型的结果与他人结果有较好的符合。同时，我们的结果表明，在爆发５００天以后，温度反而随年龄上升，可能的解释在