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Related papers: Detecting individual gravity modes in the Sun: Chi…

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We study how rotation affects observable amplitudes of high-order g- and mixed r/g-modes and examine prospects for their detection and identification. Our formalism, which is described in some detail, relies on a nonadiabatic generalization…

Astrophysics · Physics 2007-05-23 J. Daszynska-Daszkiewicz , W. A. Dziembowski , A. A. Pamyatnykh

We derive formulae connecting the frequency variations in the spectrum of solar oscillations to the dynamical quantities that are expected to change over the solar activity cycle. This is done for both centroids and the asymmetric part of…

Astrophysics · Physics 2009-11-10 W. A. Dziembowski , P. R. Goode

The solar surface and atmosphere are highly dynamic plasma environments, which evolve over a wide range of temporal and spatial scales. Large-scale eruptions, such as coronal mass ejections, can be accelerated to millions of kilometres per…

Minor bodies of the solar system can be used to measure the spectrum of the Sun as a star by observing sunlight reflected by their surfaces. To perform an accurate measurement of the radial velocity of the Sun as a star by this method, it…

Solar and Stellar Astrophysics · Physics 2015-05-06 A. F. Lanza , P. Molaro

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

During the last decades, numerous observational and theoretical efforts in the study of solar oscillations, have brought to a detailed knowledge of the interior of the Sun. While this discipline has not yet exhausted its resources and…

Solar and Stellar Astrophysics · Physics 2012-12-20 M. P. Di Mauro

The data of ground-based telescopes of Global Oscillation Network Group (GONG) obtained in the H-alpha line provide an opportunity to study the long-period oscillations of chromospheric filaments (quiescent prominence). For the first time,…

Solar and Stellar Astrophysics · Physics 2016-02-10 V. I. Efremov , L. D. Parfinenko , A. A. Soloviev

Rotation is a significant characteristic of the Sun and other stars, and it plays an important role in understanding their dynamo actions and magnetic activities. In this study, the rotation of the solar chromospheric activity is…

Solar and Stellar Astrophysics · Physics 2020-10-22 Jing-Chen Xu , Peng-Xin Gao , Xiang-Jun Shi

Using wavelet analysis approach, we can derive a measure of the disorder content of solar activity, following the temporal evolution of the so-called wavelet entropy. The interesting feature of this parameter is its ability to extract a…

Astrophysics · Physics 2015-06-24 Stefano Sello

The richness and very high accuracy of the observed frequencies of solar oscillations provide tight constraints on the structure of the solar interior and hence on the assumptions underlying the calculation of solar models. This permits the…

Astrophysics · Physics 2007-05-23 J. Christensen-Dalsgaard

We present an up-to-date estimate for the prospect of using the Astrodynamical Space Test of Relativity using Optical Devices (ASTROD) for an unambiguous detection of solar g modes (f < 400 micro Hertz) through their gravitational…

Solar oblateness has been the subject of several studies dating back to the nineteenth century. Despite diffculties, both theoretical and observational, tangible results have been achieved. However, variability of the solar oblateness with…

Solar and Stellar Astrophysics · Physics 2025-01-22 Jean P. Rozelot , Alexander G. Kosovichev , Ali Kilcik

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

As the global magnetic field of the Sun has an activity cycle, one expects to observe some variation of the dynamical properties of the flows visible in the photosphere. We investigate the flow field during the solar cycle by analysing…

Solar and Stellar Astrophysics · Physics 2017-02-15 Th. Roudier , J. M. Malherbe , G. M. Mirouh

We present the detection of l=4 and l=5 modes in power spectra of the Sun, constructed from 12 yr full-disk VIRGO-SPM data sets. A method for enhancing the detectability of these modes in asteroseismic targets is presented and applied to…

Solar and Stellar Astrophysics · Physics 2014-01-28 Mikkel Nørup Lund , Hans Kjeldsen , Jørgen Christensen-Dalsgaard , Rasmus Handberg , Victor Silva Aguirre

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

The surface differential rotation of active solar-type stars can be investigated by means of Doppler and Zeeman-Doppler Imaging, both techniques enabling one to estimate the short-term temporal evolution of photospheric structures (cools…

Astrophysics · Physics 2009-11-10 P. Petit , J. -F. Donati , A. Collier Cameron

Here we present a detailed analysis of solar acoustic mode frequencies and their rotational splittings for modes with degree up to 900. They were obtained by applying spherical harmonic decomposition to full-disk solar images observed by…

Astrophysics · Physics 2008-08-22 M. C. Rabello-Soares , S. G. Korzennik , J. Schou

In general relativity, a gravitational wave has two polarization modes (tensor mode), but it could have additional polarizations (scalar and vector modes) in the early stage of the universe, where the general relativity may not strictly…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Atsushi Nishizawa , Atsushi Taruya , Seiji Kawamura

We analyzed intermittency in the solar wind, as observed on the ecliptic plane, looking at magnetic field and velocity fluctuations between 0.3 and 1 AU, for both fast and slow wind and for compressive and directional fluctuations. Our…

Astrophysics · Physics 2015-06-24 R. Bruno , V. Carbone , L. Sorriso-Valvo , B. Bavassano