کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1778700 1523728 2017 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Time resolved spectroscopy and photometry of three little known bright cataclysmic variables: LS IV −−08° 3, HQ Monocerotis and ST Chamaeleontis
ترجمه فارسی عنوان
طیف سنجیو فوتومتری تفکیک زمانی سه متغیر تحولات بزرگ تا حدودی شناخته شده: LS IV -08 ° 3، HQ Monocerotis و ST Chamaeleontis
کلمات کلیدی
ستاره ها: novae؛ متغیرهای ترسناک؛ ستاره ها: فرد: LS IV -08 ° 3؛ ستاره ها: فرد: HQ Mon؛ ستاره ها: فرد: ST Cha
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم نجوم و فیزیک نجومی
چکیده انگلیسی


• The spectra of all investigated systems are as expected for their respective class.
• The orbital ephemeris of LS IV −−08° 3 have been improved.
• Doppler mapping of LS IV −−08° 3 reveal distinct emission sites (outer accretion disk and illuminated secondary star).
• Tentative orbital periods of 0.21462 days and 0.229 days are derived for HQ Mon and ST Cha, respectively.
• Light curves of all systems are discussed.

As part of a project to better characterize comparatively bright but so far little studied cataclysmic variables in the southern hemisphere, we have obtained spectroscopic and photometric data of the nova-like variables LS IV −−08° 3 and HQ Mon, and of the Z Cam type dwarf nova ST Cha. The spectra of all systems are as expected for their respective types. We derive improved orbital ephemeris of LS IV −−08° 3 and map its accretion disk in the light of the Hα   emission using Doppler tomography. We find that the emission has a two component origin, arising in the outer parts of the accretion disk and possibly on the illuminated face of the secondary star. The light curve of LS IV −−08° 3 exhibits a low level of flickering and indications for a modulation on the orbital period. Spectroscopy of HQ Mon suggests an orbital period of ≈ 5h.15 which is incompatible with previous (uncertain) estimates. The light curves show the typical low scale flickering of UX UMa type nova-like systems, superposed upon variations on longer time scales. During one night a modulation with a period of ≈ 41m is observed, visible for at least 4 hours. However, it does not repeat itself in other nights. A spectroscopic orbital period of ≈ 5h.5 is derived for ST Cha. A previously suspected period of 6h.8 (or alternatively 9h.6), based on historical photographic photometry is incompatible with the spectroscopic period. Moreover, we show that our new as well as previous photometry does not contain evidence for the quoted photometric period.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: New Astronomy - Volume 50, January 2017, Pages 109–119
نویسندگان
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