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تسجيل مستخدم جديدA new and improved ephemeris for the hot subdwarf eclipsing binary SDSS J082053.53+000843.4
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SDSS J082053.53+000843.4 belongs to the HW Vir family of short period binary systems and was first identified by Geier in 2011. Whilst three subsequent papers have focused on the morphology of this system, little has been published on the system period and its constancy. Here we provide the first published times of minima together with a revised ephemeris and a binary period, 0.0962404(1)d, that is four orders of magnitude more precise than previous declared values.
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We report the discovery of a bright (V=11.6 mag) eclipsing hot subdwarf binary of spectral type B with a late main sequence companion from the All Sky Automated Survey (ASAS 102322-3737.0). Such systems are called HW Vir stars after the prototype. Th
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