Report
The formation of blue large-amplitude pulsators from white-dwarf main-sequence star mergers
| العنوان: | The formation of blue large-amplitude pulsators from white-dwarf main-sequence star mergers |
|---|---|
| المؤلفون: | Zhang, Xianfei, Jeffery, C. Simon, Su, Jie, Bi, Shaolan |
| سنة النشر: | 2023 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Solar and Stellar Astrophysics |
| الوصف: | Blue large-amplitude pulsators (BLAPs) are hot low-mass stars which show large-amplitude light variations likely due to radial oscillations driven by iron-group opacities. Period changes provide evidence of both secular contraction and expansion amongst the class. Various formation histories have been proposed, but none are completely satisfactory. \citet{Zhang2017} proposed that the merger of a helium core white dwarf with a low-mass main-sequence star (HeWD+MS) can lead to the formation of some classes of hot subdwarf. We have analyzed these HeWD+MS merger models in more detail. Between helium-shell ignition and full helium-core burning, the models pass through the volume of luminosity -- gravity-- temperature space occupied by BLAPs. Periods of expansion and contraction associated with helium-shell flashes can account for the observed rates of period change. We argue that the HeWD+MS merger model provides at least one BLAP formation channel. Comment: 13 pages, 8 figures, accepted by ApJ |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2311.07812 |
| رقم الانضمام: | edsarx.2311.07812 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |