تقرير
A Benchmark White Dwarf-Ultracool Dwarf Wide Field Binary
| العنوان: | A Benchmark White Dwarf-Ultracool Dwarf Wide Field Binary |
|---|---|
| المؤلفون: | Ferreira, Thiago, Saito, Roberto K., Minniti, Dante, Mejías, Andrea, Caceres, Claudio, Alonso-García, Javier, Beamín, Juan Carlos, Smith, Leigh C., Gomez, Matías, Lucas, Philip W., Ivanov, Valentin D. |
| سنة النشر: | 2023 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Solar and Stellar Astrophysics |
| الوصف: | We present the discovery and multi-wavelength characterisation of VVV J1438-6158 AB, a new field wide-binary system consisting of a 4.6(+5.5-2.4) Gyr and Teff = 9500+/-125 K DA white dwarf (WD) and a Teff = 2400+/-50 K M8 ultracool dwarf (UCD). The projected separation of the system is a = 1236.73 au (~13.8"), and although along the line-of-sight towards the Scorpius-Centaurus (Sco-Cen) stellar association, VVV J1438-6158 AB is likely to be a field star, from a kinematic 6D probabilistic analysis. We estimated the physical, and dynamical parameters of both components via interpolations with theoretical models and evolutionary tracks, which allowed us to retrieve a mass of 0.62+/-0.18 MSun for the WD, and a mass of 98.5+/-6.2 MJup (~0.094+/-0.006 MSun) for the UCD. The radii of the two components were also estimated at 0.01309+/-0.0003 RSun and 1.22+/-0.05 RJup, respectively. VVV J1438-6158 AB stands out as a benchmark system for comprehending the evolution of WDs and low-mass companions given its status as one of the most widely separated WD+UCD systems known to date, which likely indicates that both components may have evolved independently of each other, and also being characterised by a large mass-ratio (q = 0.15+/-0.04), which likely indicates a formation pathway similar to that of stellar binary systems. Comment: Accepted for publication in MNRAS, 11 pages, 6 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2312.10158 |
| رقم الأكسشن: | edsarx.2312.10158 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |