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31.
Marian Karlický 《Space Science Reviews》2006,122(1-4):161-168
An acceleration process in the collapsing magnetic trap, formed in the flare with cusp magnetic field topology, is described.
Computations show that high-energy electrons are accumulated in the central part of the collapsing magnetic trap due to an
increase of their pitch angles. The effect explains in a natural way the formation of X-ray loop-top sources. Then, using
the model with the collapsing trap and considering only the adiabatic heating process, a possible explanation for the motion
of the X-ray loop-top source observed at the beginning of some cusp-type flares is presented. 相似文献
32.
M. van der Klis 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2675-2679
Some aspects of the rapid X-ray variability of low magnetic-field neutron stars in low-mass X-ray binaries are briefly summarized. 相似文献
33.
B.S. Shylaja 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2850-2853
The chemically peculiar (CP) stars are classified into subgroups based on the type of peculiarities. A significant fraction of these are known to be binaries. The faster evolution of the massive component leads to a white dwarf or a neutron star. Further evolution of the binary is analysed taking into consideration, the orbital parameters, effect of magnetic field, spectroscopic peculiarities and finally the statistics of CP binaries and Low Mass X-ray Binaries (LMXB).
The possible consequences of the evolution to lead to the formation of Magnetic Cataclysmic Variables (MCV) and LMXB are discussed. 相似文献
34.
N.M. Ashok R.K. Manchanda D.P.K. Banerjee S. Farrell R.K. Sood 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2777-2778
We present near-infrared spectroscopy of the massive X-ray binary 2S 0114+650. These observations covering the spectral range 1.08–2.35 μm span the region where Paschen and Brackett series recombination lines of hydrogen are expected to be seen, namely, Paβ , Brγ and Br 10–17 lines. The absence of any of these lines in emission supports earlier inferences that the optical component in 2S 0114+650 is unlikely to be a Be star but rather a B type supergiant. Near-IR photometry gives J = 8.78, H = 8.53 and K = 7.96; these values show marginal variations from earlier reported measurements. 相似文献
35.
H. Raichur B. Paul S. Naik N. Bhatt 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2785-2787
High mass X-ray binary (HMXB) pulsars are of two types, persistent and transient. 4U1538−52 is a persistent HMXB whose orbit was previously measured to be circular but the RXTE observations revealed an eccentric orbit. We observed this system with RXTE-PCA in August 2003 and our timing analysis supports the eccentric orbit of the system. However, we do not find any evidence for orbital evolution.
Rotational and tidal interactions between the stars of a closed binary system result in apsidal motion which can be measured in systems with eccentric orbit. 4U0115+63 is a Be-transient HMXB whose eccentric orbit was well-determined during its 1978 outburst. We report preliminary results from analysis of data obtained during the 1999 outburst of this source with the RXTE-PCA. 相似文献
36.
采用2θ-ω对称扫描,对(111)、(333)、(044)不同衍射面进行了ω扫描,得到了InSb不同衍射面之间强度和半峰宽度的规律;对晶片上不同位置进行了同一衍射面的ω扫描,得到半峰宽度的mapping,此外,还对材料进行了倒易空间(RSM)扫描。测试结果表明InSb材料结晶质量完好,均匀性好,符合制造良好光电器件的标准。 相似文献
37.
Tadayasu Dotani Kazumi Asai 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2752-2755
We report on the analysis of XMM-Newton archival data of EXO 0748–676. We studied changes of the continuum spectra due to the presence of photo-ionized plasma on the line of sight. We show that the ionization degree of the plasma could change largely during the X-ray bursts and the dips. These changes can significantly modify the soft-band spectrum, which was in fact observed from EXO 0748–676. We discuss the effect of the photo-ionized plasma on the continuum spectra in comparison with a frequently used model such as partial covering absorption. 相似文献
38.
M. Kalinkov K. Stavrev I. Kuneva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
An attempt is made to compare optical properties of Abell clusters with X-ray sources. 相似文献
39.
R. Hudec B. Valní
ek 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
The grazing incidence X-ray mirrors with diameters between 20 and 240 mm were produced by two different replica techniques. Five mirrors were flown in space experiments. It has been confirmed that the galvanoplastic replica mirrors are well suited for applications in space telescopes and laboratory microscopes. 相似文献
40.
P.E.J. Nulsen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Rapidly cooling gas is commonly found near the centres of clusters of galaxies. The structure of the resulting gas flows is reviewed. Total gas cooling rates of several hundred M yr−1 have been observed in a number of cases. Thermal instability and the ultimate fate of the cooled gas are discussed. The cooled gas could easily have formed a massive central galaxy. 相似文献