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Physical Sciences and Mathematics Commons

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Full-Text Articles in Physical Sciences and Mathematics

Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. Van Dyk, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning Jul 2018

Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. Van Dyk, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning

Publications

The initial-final mass relation (IFMR) of white dwarfs (WDs) plays an important role in stellar evolution. To derive precise estimates of IFMRs and explore how they may vary among star clusters, we propose a Bayesian hierarchical model that pools photometric data from multiple star clusters. After performing a simulation study to show the benefits of the Bayesian hierarchical model, we apply this model to five star clusters: the Hyades, M67, NGC 188, NGC 2168, and NGC 2477, leading to reasonable and consistent estimates of IFMRs for these clusters. We illustrate how a cluster-specific analysis of NGC 188 using its own …


Breaking The Habit: The Peculiar 2016 Eruption Of The Unique Recurrent Nova M31n 2008-12a, M. Henze, T. D. Oswalt, M. J. Darnley, S. C. Williams, M. Kato, Et Al. Apr 2018

Breaking The Habit: The Peculiar 2016 Eruption Of The Unique Recurrent Nova M31n 2008-12a, M. Henze, T. D. Oswalt, M. J. Darnley, S. C. Williams, M. Kato, Et Al.

Publications

Since its discovery in 2008, the Andromeda galaxy nova M31N 2008-12a has been observed in eruption every single year. This unprecedented frequency indicates an extreme object, with a massive white dwarf and a high accretion rate, which is the most promising candidate for the single-degenerate progenitor of a Type Ia supernova known to date. The previous three eruptions of M31N 2008-12a have displayed remarkably homogeneous multiwavelength properties: (i) from a faint peak, the optical light curve declined rapidly by two magnitudes in less than two days, (ii) early spectra showed initial high velocities that slowed down significantly within days and …


Precise Ages Of Field Stars From White Dwarf Companions, M. Fouesneau, H-W. Rix, T. Von Hippel, D. W. Hogg, H. Tian Feb 2018

Precise Ages Of Field Stars From White Dwarf Companions, M. Fouesneau, H-W. Rix, T. Von Hippel, D. W. Hogg, H. Tian

Publications

Observational tests of stellar and Galactic chemical evolution call for the joint knowledge of a star’s physical parameters, detailed element abundances, and precise age. For cool main-sequence (MS) stars the abundances of many elements can be measured from spectroscopy, but ages are very hard to determine. The situation is different if the MS star has a white dwarf (WD) companion and a known distance, as the age of such a binary system can then be determined precisely from the photometric properties of the cooling WD. As a pilot study for obtaining precise age determinations of field MS stars, we identify …