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We have studied the statistical properties of the energy of individual acoustic modes, extracted from 310 days of GOLF data near the solar minimum. The exponential distribution of the energy of each mode is clearly seen. The modes are found…

In solar-like oscillators, acoustic waves are excited by turbulent motion in the convective envelope and propagate inward, generating a variety of standing pressure modes. When combining together the power of several solar acoustic modes,…

Solar and Stellar Astrophysics · Physics 2025-08-27 E. Panetier , R. A. García , S. N. Breton , A. Jiménez , T. Foglizzo

The stochastic excitation of solar oscillations due to turbulent convection is reviewed. A number of different observational results that provide test for solar p-mode excitation theories are described. I discuss how well the stochastic…

Astrophysics · Physics 2007-05-23 Pawan Kumar

The underlying physics that generates the excitations in the global low-frequency, < 5.3 mHz, solar acoustic power spectrum is a well known process that is attributed to solar convection; However, a definitive explanation as to what causes…

Solar and Stellar Astrophysics · Physics 2015-06-05 M. Richardson , F. Hill , K. G. Stassun

Solar p-mode oscillations are excited by the work of stochastic, non-adiabatic, pressure fluctuations on the compressive modes. We evaluate the expression for the radial mode excitation rate derived by Nordlund and Stein (Paper I) using…

Astrophysics · Physics 2009-10-31 R. F. Stein , Å. Nordlund

We present a formalism for investigating the interaction between pmode oscillations and convection by analyzing realistic, three-dimensional simulations of the near-surface layers of the solar convection zone. By choosing suitable…

Astrophysics · Physics 2009-10-31 Å. Nordlund , R. F. Stein

Excitation of solar oscillations is attribued to turbulent motions in the solar convective zone. It is also currently believed that oscillations of low massive stars (M <2 Mo) - which possess an upper convective zone - are stochastically…

Astrophysics · Physics 2007-05-23 Reza Samadi

We analyze intermediate degree p-mode eigenfrequencies measured by GONG and MDI/SOHO over a solar cycle to study the source of their variability. We carry out a correlation analysis between the change in frequencies and several measures of…

Solar and Stellar Astrophysics · Physics 2011-02-11 Kiran Jain , S. C. Tripathy , F. Hill

Five-minutes oscillations is one of the basic properties of solar convection. Observations show mixture of a large number of acoustic wave fronts propagating from their sources. We investigate the process of acoustic waves excitation from…

Solar and Stellar Astrophysics · Physics 2015-05-20 I. N. Kitiashvili , A. G. Kosovichev , N. N. Mansour , A. A. Wray

Low-frequency longitudinal oscillations of a flaring coronal loop are studied numerically. In the recent work of Nakariakov et al., Astron. and Astrophys., 414, L25-L28 (2004) it has been shown that the time dependences of density and…

Astrophysics · Physics 2009-11-10 D. Tsiklauri , V. M. Nakariakov , T. D. Arber , M. J. Aschwanden

In addition to well-known mechanisms of excitation of solar and stellar oscillations by turbulent convection and instabilities, the oscillations can be excited by an impulsive localized force caused by the energy release in solar and…

Solar and Stellar Astrophysics · Physics 2015-06-18 Alexander G. Kosovichev

Acoustic power and oscillation amplitudes of radial oscillations computed for a solar model are compared with solar seismic observations. The oscillations are assumed stochastically excited by turbulence. The numerical computations are…

Astrophysics · Physics 2009-11-06 Reza Samadi , Marie-Jo Goupil , Yveline Lebreton

In a previous paper we suggested that, for a given p mode, the excitation function is the same as the component of the solar background noise that has an identical surface spherical harmonic projection (over the corresponding range of…

Astrophysics · Physics 2009-11-13 W. J. Chaplin , Y. Elsworth , T. Toutain

Recent observations and theoretical studies support the theory that solar-type oscillations are intrinsically stable but excited stochastically by the turbulent convection in the outer layers of the star. The acoustic noise generated by the…

Astrophysics · Physics 2007-05-23 Reza Samadi , Guenter Houdek

Solar-like oscillations are stochastically excited by turbulent convection. In this work we investigate changes in the acoustic oscillation power spectrum of solar-type stars by varying the treatment of convection in the equilibrium…

Astrophysics · Physics 2007-05-23 Reza Samadi , Guenter Houdek , Marie-Jo Goupil , Yveline Lebreton , Annie Baglin

Solar oscillations are expected to be excited by turbulent flows in the intergranular lanes near the solar surface. Time series recorded by the IMaX instrument aboard the {\sc Sunrise} observatory reveal solar oscillations at high…

A review on acoustic mode damping and excitation in solar-type stars is presented. Current models for linear damping rates are discussed in the light of recent low-degree solar linewidth measurements with emphasis on the…

Astrophysics · Physics 2007-05-23 G. Houdek

The frequencies of solar oscillations are known to change with solar activity. We use Principal Component Analysis to examine these changes with high precision. In addition to the well-documented changes in solar normal mode oscillations…

Astrophysics · Physics 2009-11-13 Charles S. Baldner , Sarbani Basu

Turbulent motions in stellar convection zones generate acoustic energy, part of which is then supplied to normal modes of the star. Their amplitudes result from a balance between the efficiencies of excitation and damping processes in the…

Astrophysics · Physics 2009-11-13 K. Belkacem , R. Samadi , M. J. Goupil , M. A. Dupret

We analyze and interpret SOHO/MDI data on oscillation frequency changes between 1996 and 2004 focusing on differences between activity minimum and maximum of solar cycle 23. We study only the behavior of the centroid frequencies, which…

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