اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThe supernova impostor PSN J09132750+7627410 and its progenitor
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We report the results of our follow-up campaign of the supernova impostor PSN J09132750+7627410, based on optical data covering $sim250,rm{d}$. From the beginning, the transient shows prominent narrow Balmer lines with P-Cygni profiles, with a blue-shifted absorption component becoming more prominent with time. Along the $sim3,rm{months}$ of the spectroscopic monitoring, broad components are never detected in the hydrogen lines, suggesting that these features are produced in slowly expanding material. The transient reaches an absolute magnitude $M_r=-13.60pm0.19,rm{mag}$ at maximum, a typical luminosity for supernova impostors. Amateur astronomers provided $sim4,rm{years}$ of archival observations of the host galaxy, NGC 2748. The detection of the quiescent progenitor star in archival images obtained with the Hubble Space Telescope suggests it to be an $18-20$msun white-yellow supergiant.
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