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Related papers: Low-degree modes

200 papers

Seismic structure inversions have been used to study the solar interior for decades. With the high-precision frequencies obtained using data from the Kepler mission, it has now become possible to study other solar-like oscillators using…

Solar and Stellar Astrophysics · Physics 2025-07-08 Lynn Buchele , Earl P. Bellinger , Saskia Hekker , Sarbani Basu

Despite the strong evidence that the peaks in the spectrum of solar oscillations are asymmetric, most determinations of mode frequencies have been based on fits of symmetric Lorentzian profiles to the Fourier or power spectra of oscillation…

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

Differences between observed and theoretical eigenfrequencies of the Sun have characteristics which identify them as arising predominantly from properties of the oscillations in the vicinity of the solar surface: in the super-adiabatic,…

Over the past 15 years, our knowledge of the interior of the Sun has tremendously progressed by the use of helioseismic measurements. However, to go further in our understanding of the solar core, we need to measure gravity (g) modes.…

Solar chromospheric observations of sunspot umbrae offer an exceptional view of magneto-hydrodynamic wave phenomena. In recent years, a wealth of wave signatures related to propagating magneto-acoustic modes have been presented, which…

Resonant absorption and mode conversion are both extensively studied mechanisms for wave "absorption" in solar magnetohydrodynamics (MHD). But are they really distinct? We re-examine a well-known simple resonant absorption model in a cold…

Solar and Stellar Astrophysics · Physics 2015-05-19 P. S. Cally , J. Andries

Stars are changing entities in a constant evolution during their lives. At non-secular time scales (from seconds to years) the effect of dynamical processes such as convection, rotation, and magnetic fields can modify the stellar…

Solar and Stellar Astrophysics · Physics 2019-07-09 S. Mathur , J. Ballot , R. A. Garcia

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

Since the detection of the asymptotic properties of the dipole gravity modes in the Sun, the quest to find individual gravity modes has continued. An extensive and deeper analysis of 14 years of continuous GOLF/SoHO observational data,…

Helioseismology puts strong constraints on the internal sound speed and on the rotation profile in the radiative zone. Young stars of solar type are more active and faster rotators than the Sun. So we begin to build models which include…

Solar and Stellar Astrophysics · Physics 2015-05-20 S Turck-Chieze , S Couvidat , V Duez , S Mathis , J Marques , A Palacios , L Piau

We have analyzed the full set of SOHO/MDI f- and p-mode oscillation frequencies from 1996 to date in a search for evidence of solar radius evolution during the rising phase of the current activity cycle. Like Antia et al. (2000), we find…

Astrophysics · Physics 2009-11-06 W. A. Dziembowski , P. R. Goode , J. Schou

Context. Solar gravity modes (g modes) are buoyancy waves trapped in the solar radiative zone that have been very difficult to detect at the surface. Solar g modes would complement solar pressure modes (p modes) in probing the central…

Solar and Stellar Astrophysics · Physics 2019-09-04 Vincent G. A. Böning , Huanchen Hu , Laurent Gizon

Non-Hermitian physics can be used to break time reversal symmetry and is important for interactions in a wide range of systems, from active matter and neural networks to metamaterials and non-equilibrium thermodynamics. In integrated…

We calculate the excitation of low frequency gravity waves by turbulent convection in the sun and the effect of the angular momentum carried by these waves on the rotation profile of the sun's radiative interior. We find that the gravity…

Astrophysics · Physics 2009-10-28 Pawan Kumar , Eliot J. Quataert

The quest for the solar gravity modes (or g modes) is key for the understanding of the structure and dynamics of the solar core. In this paper, we review the history of the solar g-mode detection which is separated in three nearly distinct…

Solar and Stellar Astrophysics · Physics 2013-09-20 T. Appourchaux , P. Pallé

Rossby waves play an important role in mediating the angular momentum of rotating spherical fluids, creating weather on Earth and tuning exoplanet orbits in distant stellar systems (Ogilvie 2014). Their recent discovery in the solar…

Solar and Stellar Astrophysics · Physics 2020-03-18 Krishnendu Mandal , Shravan Hanasoge

The primary inversion of the accurately measured frequencies of solar oscillations determines the mechanical properties of the Sun, i.e., the sound speed and density as a function of solar radius. In order to infer the temperature and…

Astrophysics · Physics 2007-05-23 H. M. Antia , S. M. Chitre

The dynamics of the solar core cannot be properly constrained through the analysis of acoustic oscillation modes. Gravity modes are necessary to understand the structure and dynamics of the deepest layers of the Sun. Through recent…

Astrophysics · Physics 2009-11-13 S. Mathur , A. Eff-Darwich , R. A. García , S. Turck-Chièze

High quality observations of the low-degree acoustic modes (p-modes) exist for almost two complete solar cycles using the solar spectrophotometer Mark-I, located at the Observatorio del Teide (Tenerife, Spain) and operating now as part of…

Astrophysics · Physics 2016-08-16 S. J. Jiménez-Reyes , T. Corbard , P. L. Pallé , T. Roca Cortés , S. Tomczyk