Related papers: Asteroseismic Inference for Solar-Type Stars
The ratio of the depths of spectral lines is a powerful indicator of the effective temperature. The method based on this analysis is capable of discerning small temperature variations of individual stars. We apply this spectroscopic data…
We present an asteroseismic analysis of 33 solar-type stars observed in short cadence during Campaigns (C) 1-3 of the NASA K2 mission. We were able to extract both average seismic parameters and individual mode frequencies for stars with…
Stochasticity of bright stars introduces uncertainty and bias into derived structural parameters of star clusters. We have simulated a grid of cluster $V$-band images, observed with Subaru Suprime-Cam with age, mass, and size representing a…
Asteroseismology has opened a window on the internal physics of thousands of stars, by relating oscillation spectra properties to the internal physics of stars. Mode identification, namely the process of associating a measured oscillation…
In the convective envelopes of relatively cool stars, oscillations are excited by turbulent convection. In these so-called solar-like oscillators, radial oscillation modes appear at nearly equally spaced frequencies. This spacing is…
The oscillations in solar like stars are described in terms of the phase shifts of the eigenmodes from simple sine-waves. We discuss model fitting and inversion techniques based on this representation. We analyse the periodic signatures…
Data-driven analysis methods can help to infer physical properties of red giant stars where "gold-standard" asteroseismic data are not available. The study of optical and infrared spectra of red giant stars with data-driven analyses has…
As a planet transits the face of a star, it accelerates along the line-of-sight. The changing delay in the propagation of photons produces an apparent deceleration of the planet across the sky throughout the transit. This persistent…
Stellar convection plays an important role in atmospheric dynamics, wind formation and the mass-loss processes in Asymptotic Giant Branch (AGB) stars. However, a direct characterization of convective surface structures in terms of size,…
We predict the flux and surface velocity perturbations produced by convectively excited gravity modes (g-modes) in main sequence stars. Core convection in massive stars can excite g-modes to sufficient amplitudes to be detectable with high…
The glitch signatures in $r_{010}$ for F-type stars (higher amplitude and period of the oscillatory component) are very different from those of G-type stars. The aim of this work is to analyse the signatures of these glitches and understand…
When determining absolute ages of identifiably young stellar populations, results strongly depend on which stars are studied. Cooler (K, M) stars typically yield ages that are systematically younger than warmer (A, F, G) stars by a factor…
Asteroseismic parameters allow us to measure the basic stellar properties of field giants observed far across the Galaxy. Most of such determinations are, up to now, based on simple scaling relations involving the large frequency…
Small amplitude oscillations are observed in red giant branch (RGB) stars. Data on such oscillations are a source of information about the objects, notably about properties of convection in their envelopes and about the systems these…
Variations of frequency separations of low-degree p-modes are studied over the solar activity cycle. The separations studied are obtained from the frequencies of low-degree p-modes of the Global Oscillation Network Group (GONG). 10.7 cm…
The ages of pulsating stars in clusters can be determined by isochrone fitting and it can be further improved by asteroseismic modelling. We analyse the intermediate-age open cluster NGC2477, known to suffer from differential extinction, to…
The study of stellar oscillations - asteroseismology - has revolutionized our understanding of the physical properties of the Sun, and similar potential for other stars has been demonstrated in recent years. In particular, asteroseismic…
Solar-like oscillations are stochastically excited by turbulent convection. In this work we investigate changes in the acoustic oscillation power spectrum of solar-type stars by varying the treatment of convection in the equilibrium…
Context: Mode identification has remained a major obstacle in the interpretation of pulsation spectra in rapidly rotating stars. Aims: We would like to test mode identification methods and seismic diagnostics in rapidly rotating stars,…
Subsurface convection zones are ubiquitous in early-type stars. Driven by narrow opacity peaks, these thin convective regions transport little heat but play an important role in setting the magnetic properties and surface variability of…