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Related papers: Outstanding problems in local helioseismology

200 papers

A key component of solar interior dynamics is the meridional circulation (MC), whose poleward component in the surface layers has been well observed. Time-distance helioseismic studies of the deep structure of MC, however, have yielded…

Solar and Stellar Astrophysics · Physics 2021-01-20 S. P. Rajaguru , H. M. Antia

Helioseismic inferences of large-scale flows in the solar interior necessitate accounting for the curvature of the Sun, both in interpreting systematic trends introduced in measurements as well as the sensitivity kernel that relates…

Solar and Stellar Astrophysics · Physics 2020-12-23 Jishnu Bhattacharya

The Sun's magnetic dynamo cycle features a distinct pattern: a propagating region of sunspot emergence appears around 30 degrees latitude and vanishes near the equator every 11 years. Moreover, longitudinal flows called "torsional…

During the last few decades, great effort has been made towards understanding hydrodynamical processes which determine the structure and evolution of stars. Up to now, the most stringent constraints have been provided by helioseismology and…

Solar and Stellar Astrophysics · Physics 2015-05-13 Jadwiga Daszynska-Daszkiewicz

Sunspots are prominent manifestations of solar magnetoconvection and imaging their subsurface structure is an outstanding problem of wide physical importance. Travel times of seismic waves that propagate through these structures are…

Solar and Stellar Astrophysics · Physics 2015-06-05 Shravan Hanasoge , Aaron Birch , Laurent Gizon , Jeroen Tromp

The next decade will be an exciting period for solar astrophysics, as new ground- and space-based instrumentation will provide unprecedented observations of the solar atmosphere and heliosphere. The synergy between modeling effort and…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Serena Criscuoli , Maria Kazachenko , Irina Kitashvili , Alexander Kosovichev , Valentín Martínez Pillet , Gelu Nita , Viacheslav Sadykov , Alan Wray

Ground-based synoptic solar observations provide critical contextual data used to model the large-scale state of the heliosphere. The next decade will see a combination of ground-based telescopes and space missions that will study our Sun's…

Solar and heliospheric cosmic rays provide a unique perspective in cosmic ray research: we can observe not only the particles, but also the properties of the plasmas in which the they are accelerated and propagate, using in situ and…

Space Physics · Physics 2017-02-20 T. Laitinen

Solar differential rotation exhibits a prominent feature: its cyclic variations over the solar cycle, referred to as zonal flows or torsional oscillations, are observed throughout the convection zone. Given the challenge of measuring…

Solar and Stellar Astrophysics · Physics 2024-02-27 Krishnendu Mandal , Alexander G. Kosovichev , Valery V. Pipin

Context. The Sun acts as a cornerstone of stellar physics. Thanks to spectroscopic, helioseismic and neutrino flux observations, we can use the Sun as a laboratory of fundamental physics in extreme conditions. The conclusions we draw are…

Solar and Stellar Astrophysics · Physics 2023-01-11 G. Buldgen , P. Eggenberger , A. Noels , R. Scuflaire , A. M. Amarsi , N. Grevesse , S. Salmon

In local helioseismology numerical simulations of wave propagation are useful to model the interaction of solar waves with perturbations to a background solar model. However, the solution to the equations of motions include convective modes…

Solar and Stellar Astrophysics · Physics 2010-02-11 H. Schunker , R. Cameron , L. Gizon

As the amount of asteroseismic data available continues to grow, the inability to accurately model observed oscillation frequencies is becoming a critical problem for interpreting these frequencies. A major component of this problem is the…

Solar and Stellar Astrophysics · Physics 2020-07-01 J. Schou , A. C. Birch

Near-surface flows measured by the ring-diagram technique of local helioseismology show structures that persist over multiple rotations. We examine these phenomena using data from the {\em Global Oscillation Network Group} (GONG) and the…

Solar and Stellar Astrophysics · Physics 2015-08-19 R. Howe , R. W. Komm , D. Baker , L. Harra , L. van Driel-Gesztelyi , R. S. Bogart

Downflows on the solar surface are suspected to play a major role in the dynamics of the convection zone. We investigate the existence of the long-lasting downflows whose effects influence the interior of the Sun and the outer layers. We…

Solar and Stellar Astrophysics · Physics 2021-03-05 T. Roudier , M. Švanda , J. M. Malherbe , J. Ballot , D. Korda , Z. Frank

In this contribution we briefly review some of the current issues and promises for the future by asteroseismology. We are entering a new phase in this field driven by the wealth of data that has been collected and data that will soon be…

Astrophysics · Physics 2008-11-26 Michael Bazot , Mario J. P. F. G. Monteiro , Christian W. Straka

In the course of the past several years holography has emerged as an ab initio tool in exploring strongly-time-dependent phenomena in gauge theories. These lecture notes overview recent developments in this area driven by phenomenological…

High Energy Physics - Theory · Physics 2017-01-10 Michal P. Heller

We use helioseismic holography to study the association of shallow flows with solar flare activity in about 250 large sunspot groups observed between 2010 and 2014 with the Helioseismic and Magnetic Imager on the Solar Dynamics Observatory.…

Solar and Stellar Astrophysics · Physics 2016-03-16 D. C. Braun

One goal of helioseismology is to determine the subsurface structure of sunspots. In order to do so, it is important to understand first the near-surface effects of sunspots on solar waves, which are dominant. Here we construct simplified,…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. Cameron , L. Gizon , H. Schunker , A. Pietarila

Solar oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision…

Astrophysics · Physics 2010-11-26 L. Gizon