ADIPLS—the Aarhus adiabatic oscillation package

Christensen‐Dalsgaard, J.

doi:10.1007/s10509-007-9689-z

Cited by 369 publications

(149 citation statements)

References 19 publications

Supporting

Mentioning

149

Contrasting

Order By: Relevance

“…1 We have used the "quiet-Sun" frequencies given in Table 3 of Broomhall et al (2009 Christensen-Dalsgaard 2008). In addition, the parametrization only introduces linear terms, which can be fit analytically.…”

Section: Parametrizationsmentioning

confidence: 99%

A new correction of stellar oscillation frequencies for near-surface effects

Ball

Gizon

2014

A&A

221

337

View full text Add to dashboard Cite

Context. Space-based observations of solar-like oscillations present an opportunity to constrain stellar models using individual mode frequencies. However, current stellar models are inaccurate near the surface, which introduces a systematic difference that must be corrected. Aims. We introduce and evaluate two parametrizations of the surface corrections based on formulae given by Gough (1990, LNP, 367, 283). The first we call a cubic term proportional to ν 3 /I and the second has an additional inverse term proportional to ν −1 /I, where ν and I are the frequency and inertia of an oscillation mode. Methods. We first show that these formulae accurately correct model frequencies of two different solar models (Model S and a calibrated MESA model) when compared to observed BiSON frequencies. In particular, even the cubic form alone fits significantly better than a power law. We then incorporate the parametrizations into a modelling pipeline that simultaneously fits the surface effects and the underlying stellar model parameters. We apply this pipeline to synthetic observations of a Sun-like stellar model, solar observations degraded to typical asteroseismic uncertainties, and observations of the well-studied CoRoT target HD 52265. For comparison, we also run the pipeline with the scaled power-law correction proposed by Kjeldsen et al. (2008, ApJ, 683, L175). Results. The fits to synthetic and degraded solar data show that the method is unbiased and produces best-fit parameters that are consistent with the input models and known parameters of the Sun. Our results for HD 52265 are consistent with previous modelling efforts and the magnitude of the surface correction is similar to that of the Sun. The fit using a scaled power-law correction is significantly worse but yields consistent parameters, suggesting that HD 52265 is sufficiently Sun-like for the same power-law to be applicable. Conclusions. We find that the cubic term alone is suitable for asteroseismic applications and it is easy to implement in an existing pipeline. It reproduces the frequency dependence of the surface correction better than a power-law fit, both when comparing calibrated solar models to BiSON observations and when fitting stellar models using the individual frequencies. This parametrization is thus a useful new way to correct model frequencies so that observations of individual mode frequencies can be exploited.

show abstract

Section: Parametrizationsmentioning

confidence: 99%

A new correction of stellar oscillation frequencies for near-surface effects

Ball

Gizon

2014

A&A

221

337

View full text Add to dashboard Cite

show abstract

“…Recently, Moravveji et al (2015) carried out a seismic analysis of core overshooting in a main sequence B star, obtaining satisfactory results compared to other overshooting formulations. Frequencies were computed with ADIPLS code (Christensen-Dalsgaard 2008). The code uses the adiabatic approximation and neglects the interaction between convection and oscillations.…”

Section: Stellar Code and Pulsationmentioning

confidence: 99%

Asteroseismology of 19 low-luminosity red giant stars fromKepler

Hernández

García

Corsaro

et al. 2016

A&A

View full text Add to dashboard Cite

Context. Frequencies of acoustic and mixed modes in red giant stars are now determined with high precision thanks to the long continuous observations provided by the NASA's Kepler mission. Here we consider the eigenfrequencies of nineteen low-luminosity red giant stars selected in a recent publication for a detailed peak-bagging analysis. Aims. Our objective is to obtain stellar parameters by using individual mode frequencies and spectroscopic information. Methods. We use a forward modelling technique based on a minimization procedure combining the frequencies of the p-modes, the period spacing of the dipolar modes, and the spectroscopic data. Results. Consistent results between the forward modelling technique and values derived from the seismic scaling relations are found but the errors derived using the former technique are lower. The average error for log g is 0.002 dex, compared to 0.011 dex from the frequency of maximum power, ν max , and 0.10 dex from the spectroscopic analysis. Relative errors in the masses and radii are on average 2% and 0.5% respectively, compared to 3% and 2% derived from the scaling relations. No reliable determination of the initial helium abundances and the mixing length parameters could be made. Finally, for our grid of models with given input physics, we found that low-mass stars require higher values of the overshooting parameter.

show abstract

“…The solar chemical composition is taken as X = 0.7024, Y = 0.2804 and Z = 0.0172. The adiabatic oscillation frequencies of these models are computed by ADIPLS (Christensen-Dalsgaard 2008). In this section, we test if the relations derived in Paper I are also valid for 1.3 M ⊙ < M 1.6 M ⊙ and arbitrary Z and Y .…”

Section: General Relations For Stellar Parameters From Asteroseismic mentioning

confidence: 96%

Fundamental properties of solar-like oscillating stars from frequencies of minimum Δν – II. Model computations for different chemical compositions and mass

Yıldız

Orhan

Kayhan

2015

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

The large separations between the oscillation frequencies of solar-like stars are measures of stellar mean density. The separations have been thought to be mostly constant in the observed range of frequencies. However, detailed investigation shows that they are not constant, and their variations are not random but have very strong diagnostic potential for our understanding of stellar structure and evolution. In this regard, frequencies of the minimum large separation are very useful tools. From these frequencies, in addition to the large separation and frequency of maximum amplitude, Yıldız et al. recently have developed new methods to find almost all the fundamental stellar properties. In the present study, we aim to find metallicity and helium abundances from the frequencies, and generalize the relations given by Yıldız et al. for a wider stellar mass range and arbitrary metallicity (Z) and helium abundance (Y ). We show that the effect of metallicity is significant for most of the fundamental parameters. For stellar mass, for example, the expression must be multiplied by (Z/Z ⊙ ) 0.12 . For arbitrary helium abundance, M ∝ (Y /Y ⊙ ) 0.25 . Methods for determination of Z and Y from pure asteroseismic quantities are based on amplitudes (differences between maximum and minimum values of ∆ν) in the oscillatory component in the spacing of oscillation frequencies. Additionally, we demonstrate that the difference between the first maximum and the second minimum is very sensitive to Z. It also depends on ν min1 /ν max and small separation between the frequencies. Such a dependence leads us to develop a method to find Z (and Y ) from oscillation frequencies. The maximum difference between the estimated and model Z values is about 14 per cent. It is 10 per cent for Y .

show abstract

ADIPLS—the Aarhus adiabatic oscillation package

Cited by 369 publications

References 19 publications

A new correction of stellar oscillation frequencies for near-surface effects

A new correction of stellar oscillation frequencies for near-surface effects

Asteroseismology of 19 low-luminosity red giant stars fromKepler

Fundamental properties of solar-like oscillating stars from frequencies of minimum Δν – II. Model computations for different chemical compositions and mass

Contact Info

Product

Resources

About