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Related papers: Pseudo-global Fitting of Gapped Helioseismic Data

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Mode fitting or "peak-bagging" is an important procedure in helioseismology allowing one to determine the various mode parameters of solar oscillations. Here we describe a way of reducing the systematic bias in the fits of certain mode…

Solar and Stellar Astrophysics · Physics 2011-02-11 S. T. Fletcher , W. J. Chaplin , Y. Elsworth , R. New

We introduce a modified version of a standard power spectrum `peak-bagging' technique which is designed to gain some of the advantages that fitting the entire low-degree p-mode power spectrum simultaneously would bring, but without the…

Astrophysics · Physics 2009-11-13 S. T. Fletcher , W. J. Chaplin , Y. Elsworth , R. New

Inferences of sub-surface flow velocities using local domain ring-diagram helioseismology depend on measuring the frequency splittings of oscillation modes seen in acoustic power spectra. Current methods for making these measurements…

Solar and Stellar Astrophysics · Physics 2014-03-10 Benjamin J. Greer , Bradley W. Hindman , Juri Toomre

In order to take full advantage of the long time series collected by the GONG and MDI helioseismic projects, we present here an adaptation of the rotation-corrected $m$-averaged spectrum technique in order to observe low radial-order solar…

Astrophysics · Physics 2009-06-23 David Salabert , John W. Leibacher , Thierry Appourchaux

Recent developments in instrumentation (e.g., in particular the Kepler and CoRoT satellites) provide a new opportunity to improve the models of stellar pulsations. Surface layers, rotation, and magnetic fields imprint erratic frequency…

Solar and Stellar Astrophysics · Physics 2015-06-04 M. Gruberbauer , D. B. Guenther , T. Kallinger

Normal-mode coupling is a technique applied to probe the solar interior using surface observations of oscillations. The technique, which is straightforward to implement, makes more use of the seismic information in the wavefield than other…

Solar and Stellar Astrophysics · Physics 2021-04-14 Chris S. Hanson , Shravan Hanasoge , Katepalli R. Sreenivasan

We report on the results of the latest solarFLAG hare-and-hounds exercise, which was concerned with testing methods for extraction of frequencies of low-degree solar p modes from data collected by Sun-as-a-star observations. We have used…

In this article we present our state of the art of fitting helioseismic p-mode spectra. We give a step by step recipe for fitting the spectra: statistics of the spectra both for spatially unresolved and resolved data, the use of Maximum…

Astrophysics · Physics 2009-10-30 T. Appourchaux , L. Gizon , M. C. Rabello-Soares

Helioseismology has enabled us to better understand the solar interior, while also allowing us to better constrain solar models. But now is a tremendous epoch for asteroseismology as space missions dedicated to studying stellar oscillations…

Solar and Stellar Astrophysics · Physics 2015-05-14 S. Mathur , R. A. Garcia , C. Regulo , O. L. Creevey , J. Ballot , D. Salabert , T. Arentoft , P. -O. Quirion , W. J. Chaplin , H. Kjeldsen

The GOLF instrument on board SoHO has been in operation for almost 25 years but aging of the instrument has now strongly affected its performance, especially in the low-frequency p-mode region. At the end of the SoHO mission, the…

Solar and Stellar Astrophysics · Physics 2022-02-02 S. N. Breton , P. L. Pallé , R. A. García , M. Fredslund Andersen , F. Grundahl , J. Christensen-Dalsgaard , H. Kjeldsen , S. Mathur

This report investigates the fitting of the Hessian or its inverse for stochastic optimizations using a Hessian fitting criterion derived from the preconditioned stochastic gradient descent (PSGD) method. This criterion is closely related…

Machine Learning · Statistics 2025-12-02 Xi-Lin Li

In the case of spatially-revolved helioseismic data (such as MDI, GONG, HMI), the usual mode-fitting analysis consists of fitting the 2l+1 individual m-spectra of a given multiplet (n, l) either individually or simultaneously. Such fitting…

Astrophysics · Physics 2008-10-13 D. Salabert , R. A. Garcia

Over the past two decades, helioseismology has revolutionized our understanding of the interior structure and dynamics of the Sun. Asteroseismology will soon place this knowledge into a broader context by providing structural data for…

Solar and Stellar Astrophysics · Physics 2009-10-02 T. S. Metcalfe , O. L. Creevey , J. Christensen-Dalsgaard

Context: There is a wide discrepancy in current estimates of the strength of convection flows in the solar interior obtained using different helioseismic methods applied to observations from SDO/HMI. The cause for these disparities is not…

Solar and Stellar Astrophysics · Physics 2020-01-22 Kaori Nagashima , Aaron C. Birch , Jesper Schou , Bradley W. Hindman , Laurent Gizon

We present a list of "best possible" estimates of low-degree p-mode frequencies, from 8640 days of observations made by the Birmingham Solar-Oscillations Network (BiSON). This is the longest stretch of helioseismic data ever used for this…

Solar and Stellar Astrophysics · Physics 2015-05-13 A-M. Broomhall , W. J. Chaplin , G. R. Davies , Y. Elsworth , S. T. Fletcher , S. J. Hale , B. Miller , R. New

Space observatories such as $\textit{Kepler}$ have provided data that can potentially revolutionise our understanding of stars. Through detailed asteroseismic analyses we are capable of determining fundamental stellar parameters and reveal…

Solar and Stellar Astrophysics · Physics 2018-02-01 Andrés García Saravia Ortiz de Montellano , Saskia Hekker , Nathalie Themeßl

Bias correction is a common pre-processing step applied to climate model data before it is used for further analysis. This article introduces an efficient adaptation of a well-established bias-correction method - quantile mapping - for…

Applications · Statistics 2024-06-03 Maggie D. Bailey , Douglas W. Nychka , Manajit Sengupta , Soutir Bandyopadhyay

Thanks to their high quality, new and upcoming asteroseismic observations - with CoRoT, Kepler, and from the ground... - can benefit from the experience gained with helioseismology. We focus in this paper on solar-like oscillations, for…

Astrophysics · Physics 2008-04-02 J. Ballot , T. Appourchaux , T. Toutain , M. Guittet

We report on results from the first solar Fitting at Low-Angular degree Group (solar FLAG) hare-and-hounds exercise. The group is concerned with the development of methods for extracting the parameters of low-l solar p mode data (`peak…

Quantitative helio- and asteroseismology require very precise measurements of the frequencies, amplitudes, and lifetimes of the global modes of stellar oscillation. It is common knowledge that the precision of these measurements depends on…

Astrophysics · Physics 2009-11-13 Thorsten Stahn , Laurent Gizon
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