Yazar "Love, Tom" seçeneğine göre listele
Listeleniyor 1 - 2 / 2
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Comparative study of the W UMa type binaries S Ant and ? CrA(Cambridge Univ Press, 2024) Bakis, Volkan; Budding, Edwin; Erdem, Ahmet; Love, Tom; Blackford, Mark G.; Wu, Zihao; Tang, AdamContact binaries challenge contemporary stellar astrophysics with respect to their incidence, structure, and evolution. We explore these issues through a detailed study of two bright examples: S Ant and epsilon CrA, that permit high-resolution spectroscopy at a relatively good S/N ratio. The availability of high-quality photometry, including data from the TESS satellite as well as Gaia parallaxes, allows us to apply the Russell paradigm to produce reliable up-to-date information on the physical properties of these binaries. As a result, models of their interactive evolution, such as the thermal relaxation oscillator scenario, can be examined. Mass transfer between the components is clearly evidenced, but the variability of the O'Connell effect over relatively short-time scales points to irregularities in the mass transfer or accretion processes. Our findings indicate that S Ant may evolve into an R CMa type Algol, while the low mass ratio of epsilon CrA suggests a likely merger of its components in the not-too-distant futureÖğe V410 Puppis: A useful laboratory for early stellar evolution(Oxford Univ Press, 2022) Erdem, Ahmet; Surgit, Derya; Ozkardes, Burcu; Hadrava, Petr; Rhodes, Michael D.; Love, Tom; Blackford, Mark G.New spectrometric (HERCULES) and ground-based multicolour photometric data on the multiple star V410 Puppis are combined with satellite photometry (HIPPARCOS and TESS), as well as historic astrometric observations. Absolute parameters for V410 Pup Aab are derived: M-Aa = 3.15 +/- 0.10, M-Ab = 1.83 +/- 0.08 (M-circle dot); R-Aa = 2.12 +/- 0.10, R-Ab = 1.52 +/- 0.08 (R-circle dot); a = 6.57 +/- 0.04 R-circle dot; T-Aa = 12500 +/- 1000, T-Ab = 9070 +/- 800(K), and photometric distance 350 +/- 10 (pc). We report the discovery of a low-amplitude SPB variation in the light curve and also indications of an accretion structure around V410 Pup B as well as emission cores in V410 Pup C. We argue that V410 Pup is probably a young formation connected with the Vela 2 OB Association. The combined evidence allows an age in the range 7-25 Myr from comparisons with standard stellar evolution modelling.