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Related papers: The quest for the solar g modes

200 papers

Context. Large-scale equatorial Rossby modes have been observed on the Sun over the last two solar cycles. Aims. We investigate the impact of the time-varying zonal flows on the frequencies of Rossby modes. Methods. A first-order…

Solar and Stellar Astrophysics · Physics 2020-08-05 C. R. Goddard , A. C. Birch , D. Fournier , L. Gizon

Individual mode frequencies have been detected in thousands of individual solar-like oscillators on the red giant branch (RGB). Fitting stellar models to these mode frequencies, however, is more difficult than in main-sequence stars. This…

Solar and Stellar Astrophysics · Physics 2018-05-16 W. H. Ball , N. Themeßl , S. Hekker

Helioseismic signatures of dynamo waves have recently been discovered in variations of the solar differential rotation, offering valuable insights into the type of dynamo mechanism operating in the solar convection zone. To characterize…

Solar and Stellar Astrophysics · Physics 2025-05-19 Krishnendu Mandal , Alexander G. Kosovichev , Valery V. Pipin , Sylvain G. Korzennik

The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster…

Astrophysics · Physics 2009-10-31 H. M. Antia , Sarbani Basu

The excitation of density and bending waves in Saturn's C ring by planetary oscillation modes presents a unique opportunity to learn about gas giant interiors and rotation. However, theoretical complications related to Saturn's rapid and…

Earth and Planetary Astrophysics · Physics 2022-09-14 Janosz W. Dewberry , Christopher R. Mankovich , Jim Fuller

As a part of an on-going program to explore the signature of p-modes in solar-like stars by means of high-resolution absorption lines pectroscopy, we have studied four stars (alfaCMi, etaCas A, zetaHer A and betaVir). We present here new…

Astrophysics · Physics 2009-11-10 M. Martic , J. -C. Lebrun , T. Appourchaux , S. G. Korzennik

Convection in the solar interior is thought to comprise structures on a spectrum of scales. This conclusion emerges from phenomenological studies and numerical simulations, though neither covers the proper range of dynamical parameters of…

Solar and Stellar Astrophysics · Physics 2015-06-05 Shravan Hanasoge , Thomas L. Duvall , Katepalli R. Sreenivasan

The so-called "acoustic revival mechanism" of core-collapse supernova proposed recently by the Arizona group is an interesting new possibility. Aiming to understand the elementary processes involved in the mechanism, we have calculated the…

Astrophysics · Physics 2009-11-13 Shijun Yoshida , Naofumi Ohnishi , Shoichi Yamada

We have used 4752 days of data collected by the Birmingham Solar-Oscillations Network (BiSON) to determine very precise oscillation frequencies of acoustic low-degree modes that probe the solar core. We compare the fine (small frequency)…

Current helioseismology observations allow the determination of the frequencies and surface velocity amplitudes of solar acoustic modes with exceptionally high precision. In some cases, the frequency accuracy is better than one part in a…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-07 Ilídio Lopes , Joseph Silk

Analyses of recent helioseismic data indicate that the dynamical regimes at the base of the convection zone can be different from those observed at the top, having either significantly shorter periods or non--periodic behaviour. Recently…

Astrophysics · Physics 2009-11-06 Eurico Covas , Reza Tavakol , Sergei Vorontsov , David Moss

We used the m-averaged spectrum technique ("collapsogram") to extract the low-frequency solar p-mode parameters of low- and intermediate-angular degrees (l \leq 35) in long time series of GONG and MDI observations. Rotational splittings and…

Astrophysics · Physics 2008-11-12 D. Salabert , A. Eff-Darwich , R. Howe , S. G. Korzennik

We compute the p-mode oscillation frequencies and frequency splittings that arise in a two-dimensional model of the Sun that contains toroidal magnetic fields in its interior.

Astrophysics · Physics 2008-10-29 Linghuai Li , Sarbani Basu , Sabatino Sofia , Pierre Demarque

The recent claimed detection of g modes was obtained from the analysis of the power spectrum of the time series of round-trip travel time of p modes. The goal of this paper is to reproduce these results on which the claims are based for…

Solar and Stellar Astrophysics · Physics 2019-04-24 T. Appourchaux , T. Corbard

Recent analyses of helioseismological observations seem to suggest the presence of two new phenomena connected with the dynamics of the solar convective zone. Firstly, there are present torsional oscillations with periods of about 11 years,…

Astrophysics · Physics 2009-10-31 Eurico Covas , Reza Tavakol , David Moss

There are no strong constraints placed thus far on the amplitude of internal gravity waves (IGWs) that are stochastically excited in the radiative interiors of solar-type stars. Late F-type stars have relatively thin convective envelopes…

Solar and Stellar Astrophysics · Physics 2022-11-09 Sylvain N. Breton , Allan Sacha Brun , Rafael A. García

The standard theory of pulsations deals with the frequencies and growth rates of infinitesimal perturbations in a stellar model. Modes which are calculated to be linearly driven should increase their amplitudes exponentially with time; the…

Solar and Stellar Astrophysics · Physics 2019-02-18 M. H. Montgomery , J. J. Hermes , D. E. Winget

The observed frequency shifts of the high-degree solar fundamental mode are explained using a simple geometrical optics approximation. The predicted fractional frequency shift is proportional to the mean squared velocity of the convection…

Astrophysics · Physics 2007-05-23 Andrei Gruzinov

Solar p-mode frequencies vary with solar activity. It is important to take this into account when comparing the frequencies observed from epochs that span different regions of the solar cycle. We present details of how to correct observed…

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

The observed solar p-mode velocity power spectra are compared with theoretically calculated power spectra over a range of mode degree and frequency. The shape of the theoretical power spectra depends on the depth of acoustic sources…

Astrophysics · Physics 2009-10-30 Pawan Kumar , Sarbani Basu