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Most helioseismic analyses are based on solar oscillations frequencies obtained by fitting symmetric peak profiles to the power spectra. However, it has now been demonstrated that the peaks are not symmetric. In this work we study the…

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

The variable magnetic field of the solar photosphere exhibits periodic reversals as a result of dynamo activity occurring within the solar interior. We decompose the surface field as observed by both the Wilcox Solar Observatory and the…

Solar and Stellar Astrophysics · Physics 2015-06-11 M. L. DeRosa , A. S. Brun , J. T. Hoeksema

Microturbulence, i.e. enhanced fluctuations of plasma density, electric and magnetic fields, is of great interest in astrophysical plasmas, but occurs on spatial scales far too small to resolve by remote sensing, e.g., at ~ 1-100 cm in the…

Astrophysics · Physics 2009-11-13 Gelu M. Nita , Dale E. Gary , Gregory D. Fleishman

There has for some time been evidence of variability in radiochemical solar neutrino measurements, but this evidence has seemed suspect since the cerenkov experiments have not shown similar evidence of variability. The present re-analysis…

High Energy Physics - Phenomenology · Physics 2009-11-13 P. A. Sturrock

Recent analyses of nuclear decay data show evidence of variations suggestive of a solar influence. Analyses of datasets acquired at the Brookhaven National Laboratory (BNL) and at the Physikalisch-Technische Bundesanstalt (PTB) both show…

Solar and Stellar Astrophysics · Physics 2011-08-09 Peter A. Sturrock , Ephraim Fischbach , Jere H. Jenkins

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 variations of the frequencies of the low-degree acoustic oscillations in the Sun induced by magnetic activity show a dependence with radial order. The frequency shifts are observed to increase towards higher-order modes to reach a…

Solar and Stellar Astrophysics · Physics 2018-04-04 D. Salabert , C. Régulo , F. Pérez Hernández , R. A. García

Context: Recent observations of HD49933 by the space-photometric mission CoRoT provide photometric evidence of solar type oscillations in a star other than our Sun. The first published reduction, analysis, and interpretation of the CoRoT…

Astrophysics · Physics 2015-05-13 T. Kallinger , M. Gruberbauer , D. B. Guenther , L. Fossati , W. W. Weiss

In the Sun, the properties of acoustic modes are sensitive to changes in the magnetic activity. In particular, mode frequencies are observed to increase with increasing activity level. Thanks to CoRoT and Kepler, such variations have been…

We present first direct evidence of modulation in the $K$-band of Blazhko-type RR Lyrae stars that are identified by their secular modulations in the I-band data of OGLE-IV. A method has been developed to decompose the $K$-band light…

Solar and Stellar Astrophysics · Physics 2018-01-31 J. Jurcsik , G. Hajdu , I. Dékány , J. Nuspl , M. Catelan , E. K. Grebel

We establish that global solar p-mode frequencies can be measured with sufficient precision on time scales as short as nine days to detect activity-related shifts. Using ten years of GONG data, we report that mode-mass and error-weighted…

Astrophysics · Physics 2009-02-10 S. C. Tripathy , F. Hill , K. Jain , J. W. Leibacher

We investigate the behavior of the intermediate-degree mode frequencies of the sun during the current extended minimum phase to explore the time-varying conditions in the solar interior. Using contemporaneous helioseismic data from GONG and…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. C. Tripathy , K. Jain , F. Hill , J. W. Leibacher

The intermittency of density fluctuations in the solar wind at kinetic scales has been examined using high time resolution Faraday cup measurements from the Spektr-R spacecraft. It was found that the probability density functions (PDFs) of…

Space Physics · Physics 2014-06-23 C. H. K. Chen , L. Sorriso-Valvo , J. Šafránková , Z. Němeček

The Sun's global inertial modes are very sensitive to the solar differential rotation and to properties of the deep solar convection zone which are currently poorly constrained. These properties include the superadiabatic temperature…

Solar and Stellar Astrophysics · Physics 2024-12-25 Laurent Gizon , Yuto Bekki , Aaron C. Birch , Robert H. Cameron , Damien Fournier , Jordan Philidet , B. Lekshmi , Zhi-Chao Liang

The nonlinear decay of Langmuir/$\mathcal{Z}$-mode waves into electromagnetic $\mathcal{Z}$-mode wave radiation at the plasma frequency is observed for the first time in the solar wind. This finding was enabled by the unprecedented…

Plasma Physics · Physics 2026-01-27 F. J. Polanco-Rodríguez , C. Krafft , P. Savoini

On the one hand, several types of global-scale inertial modes of oscillation have been observed on the Sun. They include the equatorial Rossby modes, critical-latitude modes, and high-latitude modes. On the other hand, the columnar…

Solar and Stellar Astrophysics · Physics 2022-06-08 Yuto Bekki , Robert H. Cameron , Laurent Gizon

This paper examines long-term temporal and spatial fluctuations in the solar rotation (more than four solar cycles) by investigating radio emission escapes from various layers of the solar atmosphere during the years 1967-2010. The flux…

Solar and Stellar Astrophysics · Physics 2021-07-06 Vivek Kumar Singh , Satish Chandra , Sanish Thomas , Som Kumar Sharma , Hari Om Vats

We use very precise frequencies of low-degree solar-oscillation modes measured from 4752 days of data collected by the Birmingham Solar-Oscillations Network (BiSON) to derive seismic information on the solar core. We compare these…

We investigate the scalar mode quadrupole radiation of gravitational waves in $F(R)$ modified gravity. In $F(R)$ gravity a massive scalar mode appears in the gravitational waves. We find explicit expressions for the quadrupole radiation and…

General Relativity and Quantum Cosmology · Physics 2023-07-19 Tomohiro Inagaki , Masahiko Taniguchi

The total amount of solar irradiance falling on the earth's surface is an important area of study amongst the photo-voltaic (PV) engineers and remote sensing analysts. The received solar irradiance impacts the total amount of generated…

Instrumentation and Methods for Astrophysics · Physics 2018-04-23 Shilpa Manandhar , Soumyabrata Dev , Yee Hui Lee , Yu Song Meng