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Related papers: Probabilistic Inversions for Time-Distance Heliose…

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Normal modes are coupled by the presence of perturbations in the Sun, providing a novel and under-appreciated helioseismic technique with which to image the solar interior. The process of measuring coupling between normal modes is…

Solar and Stellar Astrophysics · Physics 2018-07-18 Shravan Hanasoge

In contrast to the situation in a laboratory, the study of the solar atmosphere has to be pursued without direct access to the physical conditions of interest. Information is therefore incomplete and uncertain and inference methods need to…

Solar and Stellar Astrophysics · Physics 2018-01-24 I. Arregui

According to time-distance helioseismology, information about internal fluid motions is encoded in the travel times of solar waves. The inverse problem consists of inferring 3-D vector flows from a set of travel-time measurements. Here we…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. Svanda , L. Gizon , S. M. Hanasoge , S. D. Ustyugov

Inversions for local helioseismology are an important and necessary step for obtaining three-dimensional maps of various physical quantities in the solar interior. Frequently, the full inverse problems that one would like to solve prove…

Solar and Stellar Astrophysics · Physics 2015-04-01 J. Jackiewicz , A. C. Birch , L. Gizon , S. M. Hanasoge , T. Hohage , J. -B. Ruffio , M. Svanda

Stokes inversion techniques are very powerful methods for obtaining information on the thermodynamic and magnetic properties of solar and stellar atmospheres. In recent years, very sophisticated inversion codes have been developed that are…

Solar and Stellar Astrophysics · Physics 2022-03-23 C. J. Díaz Baso , A. Asensio Ramos , J. de la Cruz Rodríguez

[abridged] Inversion techniques are the most powerful methods to obtain information about the thermodynamical and magnetic properties of solar and stellar atmospheres. In the last years, we have witnessed the development of highly…

Astrophysics · Physics 2009-11-13 A. Asensio Ramos , M. J. Martinez Gonzalez , J. A. Rubino-Martin

Being able to image active regions on the Sun's far side is useful for modeling the global-scale magnetic field around the Sun, and for predicting the arrival of major active regions that rotate around the limb onto the near side.…

Solar and Stellar Astrophysics · Physics 2020-01-08 Junwei Zhao , Dominick Hing , Ruizhu Chen , Shea Hess Webber

Supergranulation is one of the most visible length scales of solar convection and has been studied extensively by local helioseismology. We use synthetic data computed with the Seismic Propagation through Active Regions and Convection…

Solar and Stellar Astrophysics · Physics 2015-06-12 D. E. Dombroski , A. C. Birch , D. C. Braun , S. M. Hanasoge

Mapping the large-scale subsurface plasma flow profile within the Sun has been attempted using various methods for several decades. One such flow in particular is the meridional circulation, for which numerous studies have been published.…

Solar and Stellar Astrophysics · Physics 2023-08-23 Aleczander Herczeg , Jason Jackiewicz

Time-distance helioseismology provides information about vector flows in the near-surface layers of the Sun by measuring wave travel times between points on the solar surface. Specific spatial averages of travel times have been proposed for…

Solar and Stellar Astrophysics · Physics 2015-01-05 Jan Langfellner , Laurent Gizon , Aaron C. Birch

Helioseismic waves observable at the solar surface can be used to probe the properties of the Sun's interior. By measuring helioseismic travel times between different location on the surface, flows and other interior properties can be…

Solar and Stellar Astrophysics · Physics 2021-03-24 Thomas Hartlep , Junwei Zhao

Inverse problems use physical measurements along with a computational model to estimate the parameters or state of a system of interest. Errors in measurements and uncertainties in the computational model lead to inaccurate estimates. This…

Numerical Analysis · Mathematics 2015-02-02 Vishwas Rao , Adrian Sandu

Bayesian Inference is a powerful approach to data analysis that is based almost entirely on probability theory. In this approach, probabilities model {\it uncertainty} rather than randomness or variability. This thesis is composed of a…

Astrophysics · Physics 2008-09-08 Brendon J. Brewer

Helioseismic holography is a useful method to detect active regions on the Sun's far side and improve space weather forecasts. We aim to improve helioseismic holography by using a clear formulation of the problem, an accurate forward solver…

Solar and Stellar Astrophysics · Physics 2023-01-18 Dan Yang , Laurent Gizon , Hélène Barucq

In a variety of scientific applications we wish to characterize a physical system using measurements or observations. This often requires us to solve an inverse problem, which usually has non-unique solutions so uncertainty must be…

Geophysics · Physics 2022-05-19 Xin Zhang , Muhammad Atif Nawaz , Xuebin Zhao , Andrew Curtis

Previous helioseismology of sunspots has been sensitive to both the structural and magnetic aspects of sunspot structure. We aim to develop a technique that is insensitive to the magnetic component so the two aspects can be more readily…

Solar and Stellar Astrophysics · Physics 2018-06-07 T. L. Duvall , P. S. Cally , D. Przybylski , K. Nagashima , L. Gizon

A major goal of helioseismology is the three-dimensional reconstruction of the three velocity components of convective flows in the solar interior from sets of wave travel-time measurements. For small amplitude flows, the forward problem is…

Numerical Analysis · Mathematics 2017-03-28 D. Fournier , L. Gizon , M. Holzke , T. Hohage

Over the last decade, a series of applied mathematics papers have explored a type of inverse problem--called by a variety of names including "inverse sensitivity", "pushforward based inference", "consistent Bayesian inference", or…

Methodology · Statistics 2022-11-30 Peter W. Marcy , Rebecca E. Morrison

Supergranules create a peak in the spatial spectrum of photospheric velocity features. They have some properties of convection cells but their origin is still being debated in the literature. The time-distance helioseismology constitutes a…

Solar and Stellar Astrophysics · Physics 2021-02-24 David Korda , Michal Švanda

Seismic tomography is a methodology to image the interior of solid or fluid media, and is often used to map properties in the subsurface of the Earth. In order to better interpret the resulting images it is important to assess imaging…

Geophysics · Physics 2020-05-20 Xin Zhang , Andrew Curtis