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Related papers: Low-Degree High-Frequency p and g Modes in the Sol…

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The Rapid Oscillations in the Solar Atmosphere (ROSA) instrument reveals solar atmospheric fluctuations at high frequencies. Spectra of variations of the G-band intensity (IG) and CaII K-line intensity (IK) show correlated fluctuations…

Solar and Stellar Astrophysics · Physics 2015-06-03 J. K. Lawrence , A. C. Cadavid , D. J. Christian , D. B. Jess , M. Mathioudakis

Knowledge of the geometry of pulsational modes is a prerequisite for seismic modelling of stars. In the case of slowly pulsating B-type (SPB) pulsators, the simple zero-rotation approach so far used for mode identification is usually not…

Solar and Stellar Astrophysics · Physics 2015-06-24 W. Szewczuk , J. Daszyńska-Daszkiewicz

Solar activity and helioseismology show the limitation of the standard solar model and call for the inclusion of dynamical processes in both convective and radiative zones. We concentrate here on the radiative zone and first show the…

Solar and Stellar Astrophysics · Physics 2014-11-20 Sylvaine Turck-Chieze , Ana Palacios , Joao Marques , P. Nghiem

We study temporal variations in the amplitudes and widths of high-degree acoustic modes by applying the ring-diagram technique to the GONG+, MDI and HMI Dopplergrams during the declining phase of cycle 23 and rising phase of cycle 24. The…

Solar and Stellar Astrophysics · Physics 2015-06-15 Olga Burtseva , Sushant Tripathy , Richard Bogart , Kiran Jain , Rachel Howe , Frank Hill , Maria Cristina Rabello-Soares

Although there are now some tentative signs that the start of cycle 24 has begun there is still considerable interest in the somewhat unusual behaviour of the current solar minimum and the apparent delay in the true start of the next cycle.…

Solar and Stellar Astrophysics · Physics 2010-03-23 Stephen Fletcher , Roger New , Anne-Marie Broomhall , William Chaplin , Yvonne Elsworth

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

Recent progress in realistic simulations of solar convection have given us an unprecedented opportunity to evaluate the robustness of solar interior structures and dynamics obtained by methods of local helioseismology. We present results of…

We explore the sensitivity of the frequencies of low-degree solar p-modes to near-surface magnetic flux on different spatial scales and strengths, specifically to active regions with strong magnetic fields and ephemeral regions with weak…

The impact of global acoustic modes on the 8B neutrino flux time series is computed for the first time. It is shown that the time fluctuations of the 8B neutrino flux depend on the amplitude of acoustic eigenfunctions in the region where…

Solar and Stellar Astrophysics · Physics 2013-10-15 Ilidio Lopes

Solar oscillation frequencies change with the level of magnetic activity. Localizing subsurface magnetic field concentrations in the Sun with helioseismology will help us to understand the solar dynamo. Because the magnetic fields are not…

Solar and Stellar Astrophysics · Physics 2018-02-28 René Kiefer , Markus Roth

In helioseismic studies, an observational parameter of primary concern is the P-angle, the angle along which lies the solar axis of rotation for a given image. For the six observing sites employed by The Global Oscillation Network Group…

Solar and Stellar Astrophysics · Physics 2023-04-17 Anna L. H. Hughes , Irene Gonzalez-Hernandez , Sean G. McManus , Kiran Jain , Sushanta C. Tripathy

The Sun's surface vibrates in characteristic 5-minute oscillations, known as p-modes, generated by sound waves trapped within the convection zone. Although these oscillations have long been hypothesized to reach into the solar wind, direct…

We consider a generalized model of seismic-wave propagation that takes into account the effect of a central magnetic field in the Sun. We determine the g-mode spectrum in the perturbative magnetic field limit using a one-dimensional…

Astrophysics · Physics 2008-12-18 T. I. Rashba , V. B. Semikoz , J. W. F. Valle

The recent discovery of inertial waves on the surface of the Sun offers new possibilities to learn about the solar interior. These waves are long-lived with a period on the order of the Sun rotation period ($\sim$27 days) and are sensitive…

Solar and Stellar Astrophysics · Physics 2024-03-25 Tram Thi Ngoc Nguyen , Thorsten Hohage , Damien Fournier , Laurent 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

Magnetic fields in the stellar interiors are key candidates to explain observed core rotation rates inside solar-like stars along their evolution. Recently, asteroseismic estimates of radial magnetic field amplitudes near the…

Solar and Stellar Astrophysics · Physics 2024-07-19 Shatanik Bhattacharya , Srijan Bharati Das , Lisa Bugnet , Subrata Panda , Shravan M. Hanasoge

Using even-order frequency splitting coefficients of global p-modes it is possible to infer the magnetic field in the solar interior as a function of radial distance and latitude. Results obtained using GONG and MDI data are discussed.…

Astrophysics · Physics 2007-05-23 H. M. Antia

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

Precise numerical standard solar models (SSMs) now agree with one another and with helioseismological observations in the convective and outer radiative zones. Nevertheless these models obscure how luminosity, neutrino production and g-mode…

Astrophysics · Physics 2009-10-28 Sidney A. Bludman , Dallas C. Kennedy

Stars between two and three solar masses rotate rapidly on the main sequence, and their rotation rates in the core helium burning (secondary clump) phase can therefore be used to test models of angular momentum loss used for gyrochronology…

Solar and Stellar Astrophysics · Physics 2018-12-12 Jamie Tayar , Marc H. Pinsonneault