کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1779262 1021986 2011 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The relation between the long-term X-ray and optical activity of the polar AM Her (RX J1816.2 + 4952)
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم نجوم و فیزیک نجومی
پیش نمایش صفحه اول مقاله
The relation between the long-term X-ray and optical activity of the polar AM Her (RX J1816.2 + 4952)
چکیده انگلیسی
We analyze the relation between the long-term (1996-2009) activity of the polar AM Her in the optical and hard X-ray spectral regions. We investigate the mean values of the intensities in the individual high-state episodes. We made use of the ASM/RXTE observations for a time-series analysis of the long-term variations in the 1.5-12 keV band. The optical data came from the AFOEV database. We reveal a complicated relation between the optical (IO) and hard X-ray intensity (IX). We argue that our observations cannot be explained by the variations of the orbital modulation in the high-state. Also, the precession of the spin axis of the white dwarf or asynchronous rotation of this object are unlikely in our case. We show that the basic properties of the emitting region (s) is (are) established in the early phase (several days long) of the high-state episode but they are not reproduced for every episode. The increase of the mass transfer rate from the donor that switches the polar from the low to the high-state also establishes a division of the emission released during the accretion process into various spectral regions that is valid only for a given episode. These results enable us a better understanding of the multifrequency behavior of polars on long time-scales.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: New Astronomy - Volume 16, Issue 6, October 2011, Pages 405-411
نویسندگان
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