Zobrazeno 1 - 10
of 241
pro vyhledávání: '"Townsend, R. H."'
Numerical computations of stellar oscillations for models representative of B-type stars predict fewer modes to be excited than observations reveal from modern space-based photometric data. One shortcoming of state-of-the-art evolution models of B-ty
Externí odkaz:
http://arxiv.org/abs/2405.08864
Autor:
Townsend, R. H. D., Kawaler, S. D.
Publikováno v:
RNAAS, 7, 166 (023)
Kawaler et al. (1985) present a variational expression for the eigenfrequencies associated with stellar oscillations. We highlight and correct a typographical error in the weight functions appearing in these expressions, and validate the correction n
Externí odkaz:
http://arxiv.org/abs/2308.00785
Autor:
Townsend, R. H. D., Sun, M.
We examine the reasons for discrepancies between two alternative approaches to modeling small-amplitude tides in binary systems. The 'direct solution' (DS) approach solves the governing differential equations and boundary conditions directly, while t
Externí odkaz:
http://arxiv.org/abs/2306.06429
Autor:
Oey, M. S., Castro, N., Renzo, M., Vargas-Salazar, I., Suffak, M. W., Ratajczak, M., Monnier, J. D., Szymanski, M. K., Phillips, G. D., Calvet, N., Chiti, A., Micheva, G., Rasmussen, K. C., Townsend, R. H. D.
We present 18 years of OGLE photometry together with spectra obtained over 12 years, revealing that the early Oe star AzV 493 shows strong photometric (Delta I < 1.2 mag) and spectroscopic variability with a dominant, 14.6-year pattern and ~40-day os
Externí odkaz:
http://arxiv.org/abs/2301.11433
We describe new functionality in the GYRE stellar oscillation code for modeling tides in binary systems. Using a multipolar expansion in space and a Fourier-series expansion in time, we decompose the tidal potential into a superposition of partial ti
Externí odkaz:
http://arxiv.org/abs/2301.06599
Gamma-rays can be produced by the interaction of a relativistic jet and the matter of the stellar wind in the subclass of massive X-ray binaries known as “microquasars”. The relativistic jet is ejected from the surroundings of the compact object
Externí odkaz:
http://opus.kobv.de/ubp/volltexte/2008/1821/
By quantitatively fitting simple emission line profile models that include both atomic opacity and porosity to the Chandra X-ray spectrum of ζ Pup, we are able to explore the trade-offs between reduced mass-loss rates and wind porosity. We find that
Externí odkaz:
http://opus.kobv.de/ubp/volltexte/2008/1811/
Autor:
Townsend, R. H. D.
In this contribution, I discuss some basic techniques that can be used to simulate radiative transfer through porous media. As specific examples, I consider scattering transfer through a clumped slab, and X-ray emission line formation in a clumped wi
Externí odkaz:
http://opus.kobv.de/ubp/volltexte/2008/1786/
Autor:
Chontos, Ashley, Huber, Daniel, Berger, Travis A., Kjeldsen, Hans, Serenelli, Aldo M., Aguirre, Victor Silva, Ball, Warrick H., Basu, Sarbani, Bedding, Timothy R., Chaplin, William J., Claytor, Zachary R., Corsaro, Enrico, García, Rafael A., Howell, Steve B., Lundkvist, Mia S., Mathur, Savita, Metcalfe, Travis S., Nielsen, Martin B., Ong, Jia Mian Joel, Orhan, Zeynep Çelik, Örtel, Sibel, Salama, Maïssa, Stassun, Keivan G., Townsend, R. H. D., van Saders, Jennifer L., Winther, Mark, Yildiz, Mutlu, Butler, R. Paul, Tinney, C. G., Wittenmyer, Robert A.
Asteroseismology of bright stars has become increasingly important as a method to determine fundamental properties (in particular ages) of stars. The Kepler Space Telescope initiated a revolution by detecting oscillations in more than 500 main-sequen
Externí odkaz:
http://arxiv.org/abs/2012.10797
The blue-straggler binary WOCS 5379 is a member of the old (6-7 Gyr) open cluster NGC 188. WOCS 5379 comprises a blue straggler star with a white dwarf companion in a 120-day eccentric orbit. Combined with the orbital period, this helium white dwarf
Externí odkaz:
http://arxiv.org/abs/2012.08502