منابع مشابه
On Temperature and Abundance Effects During an X-Ray Flare on σ Geminorum
We compare quiescent and flare X-ray spectra of the RS CVn binary σ Gem obtained with the Chandra and XMMNewton grating spectrometers. We find that in addition to an overall 25% flux increase, which can be ascribed to variations in the system’s quiescence activity over the 15 months that passed between the observations, there is a hot plasma component of kTe >∼ 3 keV that arises with the flare....
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هدف از انجام این مطالعه ، بررسی اثرات استفاده از استراتژی های شناختی یعنی "نت برداری" و "زیر خط کردن" بر روی عملکرد درک مطلب زبان آموزان ایرانی می باشد. به این منظور، 60 زبان آموز دختر سال چهارم دبیرستان از طریق آزمون پیشرفت زبان انگلیسی (نلسون)، از یک جامعه آماری بزرگتر انتخاب شدند. سپس به صورت تصادفی به سه گروه که هر گروه شامل ?0 دانش آموز همسان بود، تقسیم شدند: دو گروه آزمایش(گروه "نت برداری...
15 صفحه اولNova Geminorum No. 2 as a Wolf-Rayet Star.
It has been known for many years that the spectrum of temporary stars or Novae develops in a later stage into a spectrum nearly identical with that of planetary nebulae. First observed in the case of Nova Aurigae of 1891, the same result has been found to hold for all of the temporary stars observed since that time, including the most important Nova of recent years, Nova Persei of 1901. The que...
متن کاملLong-term changes of the Be star OT Geminorum
We investigate the character of light variability of the bright Be star OT Gem. Two phases of the long-term light changes were distinguished: – a quiet phase which is characterized by mild light changes; and – an active phase in which the sudden increases of brightness up to 0. m 4 in V occur. During the active phases, a cyclic oscillation of brightness of a period between 70 and 80 days is pre...
متن کاملOptical spectroscopy of the dwarf nova U Geminorum
The dwarf nova U Gem is unique in having a direct measurement of the K-velocity of its white dwarf from HST spectra (K 1 = 107 ± 2 km s −1 , Long et al. 1999). We present high-resolution optical spectra of the dwarf nova U Gem in quiescence taken to test the accuracy to which the HST value can be recovered from optical data. We find that, even with data of very high signal-to-noise ratio on thi...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 1954
ISSN: 0004-6256
DOI: 10.1086/107086