Results 21 to 30 of about 1,037 (263)

Cracking Strange Stars by Torsional Oscillations

open access: yesUniverse, 2018
Strange stars are one of the possible compact stellar objects formed in the core collapse of supernovae. These hypothetical stars are made by deconfined quark matter and are selfbound.
Francesco Tonelli, Massimo Mannarelli
doaj   +1 more source

Overstable Convective Modes in a Polytropic Stellar Atmosphere

open access: yesThe Astrophysical Journal, 2023
Within the convection zone of a rotating star, the presence of the Coriolis force stabilizes long-wavelength convective modes. These modes, which would have been unstable if the star lacked rotation, are called overstable convective modes or thermal ...
Bradley W. Hindman, Rekha Jain
doaj   +1 more source

Techniques for observing stellar oscillations [PDF]

open access: yesSymposium - International Astronomical Union, 1988
Although stellar oscillations have been observed for more than two centuries, the demands of asteroseismology require new observations of substantially higher precision. Two major techniques are reviewed: Doppler spectroscopy and photometry. Fundamental limitations are described using the sun as a representative stellar target. The current state of the
openaire   +1 more source

Chaotic Dynamics of Stellar Spin in Binaries and the Production of Misaligned Hot Jupiters

open access: yesEPJ Web of Conferences, 2015
Motivated by observed hot Jupiter systems with high stellar obliquities, we examine the dynamics of stellar spin in planetary systems with distant stellar companions, with inclinations sufficiently high so that the planet undergoes Kozai-Lidov ...
Anderson Kassandra R.   +2 more
doaj   +1 more source

Kolmogorov Unstable Stellar Oscillations [PDF]

open access: yesSolar Physics, 1983
AbstractWe survey the mathematics of non-linear Hamiltonian oscillations with emphasis being laid on the more recently discovered Kolmogorov instability. In the context of radial adiabatic oscillations of stars this formalism predicts a Kolmogorov instability even at low oscillation energies, provided that sufficiently high linear asymptotic modes have
openaire   +1 more source

Stellar oscillations in modified gravity [PDF]

open access: yesPhysical Review D, 2013
Starting from the equations of modified gravity hydrodynamics, we derive the equ tions of motion governing linear, adiabatic, radial perturbations of stars in scalar-tensor theories. There are two new features: first, the eigenvalue equation for the period of stellar oscillations is modified such that the eigenfrequencies are always larger than ...
openaire   +2 more sources

Asteroseismic modelling of the Binary HD 176465

open access: yesEPJ Web of Conferences, 2017
The detection and analysis of oscillations in binary star systems is critical in understanding stellar structure and evolution. This is partly because such systems have the same initial chemical composition and age.
Nsamba B.   +6 more
doaj   +1 more source

Latitudinal Propagation of Thermal Rossby Waves in Stellar Convection Zones

open access: yesThe Astrophysical Journal, 2023
Using an analytic model, we derive the eigenfrequencies for thermal Rossby waves that are trapped radially and latitudinally in an isentropically stratified atmosphere. We ignore the star’s curvature and work in an equatorial f-plane geometry.
Rekha Jain, Bradley W. Hindman
doaj   +1 more source

Stellar oscillations - I - The adiabatic case [PDF]

open access: yesEAS Publications Series, 2015
This lecture on adiabatic oscillations is intended to present the basis of asteroseismology and to serve as an introduction for other lectures of the EES 2014. It also exposes the state-of-the-art of solar-like oscillation analysis, as revealed by the space missions CoRoT and Kepler.
openaire   +2 more sources

Dark matter induced stellar oscillations

open access: yesMonthly Notices of the Royal Astronomical Society: Letters, 2023
ABSTRACT It has been hypothesized that dark matter is comprised of ultra-light bosons whose collective phenomena can be described as a scalar field undergoing coherent oscillations. Examples include axion and fuzzy dark matter models. In this ultra-light dark matter (ULDM) scenario, the harmonic variation in the field’s energy–momentum ...
Sakstein, J., Saltas, Ippocratis D.
openaire   +3 more sources

Home - About - Disclaimer - Privacy