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Related papers: Source depth for solar p-modes

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Solar gravity modes (or g modes) -- oscillations of the solar interior for which buoyancy acts as the restoring force -- have the potential to provide unprecedented inference on the structure and dynamics of the solar core, inference that…

The aim of this work is to give new observational constraints on solar surface flows by determining the horizontal scale dependence of the velocity and intensity fields, as represented by their power spectra, and to offer some theoretical…

Solar and Stellar Astrophysics · Physics 2015-05-14 M. Rieutord , T. Roudier , F. Rincon , J. -M. Malherbe , N. Meunier , T. Berger , Z. Frank

Solar gravity (g) modes propagate within the radiative part of the solar interior and are highly sensitive to the physical conditions of the solar core. They would represent the best tool to infer the structure and dynamics of the radiative…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. Mathur , R. A. Garcia , A. Eff-Darwich

Spectra of the cellular photospheric flows are determined from full-disk Doppler velocity observations acquired by the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO) spacecraft. Three different…

Solar and Stellar Astrophysics · Physics 2015-10-01 David H. Hathaway , Thibaud Teil , Aimee A. Norton , Irina Kitiashvili

Space-borne missions CoRoT and Kepler have provided a rich harvest of high-quality photometric data for solar-like pulsators. It is now possible to measure damping rates for hundreds of main-sequence and thousands of red-giant. However,…

Solar and Stellar Astrophysics · Physics 2019-05-01 K. Belkacem , F. Kupka , R. Samadi , H. Grimm-Strele

We have analysed the recently available GONG p-mode frequencies and splitting coefficients for a period of three and half years, including the rapidly rising phase of solar cycle 23. The analysis of mean frequency shift with different…

Astrophysics · Physics 2009-10-31 Kiran Jain , S. C. Tripathy , A. Bhatnagar

We present a list of "best possible" estimates of low-degree p-mode frequencies, from 8640 days of observations made by the Birmingham Solar-Oscillations Network (BiSON). This is the longest stretch of helioseismic data ever used for this…

Solar and Stellar Astrophysics · Physics 2015-05-13 A-M. Broomhall , W. J. Chaplin , G. R. Davies , Y. Elsworth , S. T. Fletcher , S. J. Hale , B. Miller , R. New

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

Sunspots are known to be strong absorbers of solar oscillation modal power. The most convincing way to demonstrate this is done via Fourier-Hankel decomposition (FHD), where the local oscillation field is separated into in- and outgoing…

Solar and Stellar Astrophysics · Physics 2021-06-04 Matthias Waidele , Markus Roth , Gangadharan Vigeesh , Kolja Glogowski

We present observational constraints on the solar chromospheric heating contribution from acoustic waves with frequencies between 5 and 50 mHz. We utilize observations from the Dunn Solar Telescope in New Mexico complemented with…

Solar and Stellar Astrophysics · Physics 2021-11-03 Momchil E. Molnar , Kevin P. Reardon , Steven R. Cranmer , Adam F. Kowalski , Yi Chai , Dale Gary

We present new results on the structure of the solar core, obtained with new sets of frequencies of solar low-degree p modes obtained from the BiSON network. We find that different methods used in extracting the different sets of…

Solar and Stellar Astrophysics · Physics 2009-07-22 Sarbani Basu , William J. Chaplin , Yvonne Elsworth , Roger New , Aldo M. Serenelli

We have analyzed the local acoustic spectra of small regions over the solar surface at different locations from disk center to limb via the technique of ring diagrams. It is found that the frequency shifts between velocity and intensity is…

Astrophysics · Physics 2007-05-23 S. C. Tripathy , Kiran Jain , Frank Hill , C. G. Toner

We present the preliminary results of a new survey of radio sources using the Ryle telescope at 15.2 GHz. This is the highest frequency at which a survey has been done that is relevant to the issue of radio source contamination in CMB…

In the present work we show robust indications of the existence of g modes in the Sun using 10 years of GOLF data. The present analysis is based on the exploitation of the collective properties of the predicted low-frequency (25 to 140…

Characterising spectral variability of radio sources is a technique that offers the ability to determine the astrophysics of the intervening media, source structure, emission and absorption processes. We present broadband (0.072--10 GHz)…

Astrophysics of Galaxies · Physics 2022-04-06 K. Ross , N. Hurley-Walker , N. Seymour , J. R. Callingham , T. J. Galvin , M. Johnston-Hollitt

The solar magnetic activity consists of two periodic components: the main cycle with a period of 11 yr and a shorter cycle with a period of ~2 yrs. The origin of this second periodicity is still not well understood. We use almost 15 yrs of…

Solar and Stellar Astrophysics · Physics 2015-06-11 R. Simoniello , K. Jain , S. C. Tripathy , S. Turck-Chieze , W. Finsterle , M. Roth

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…

(Abridged) Wavelet analysis can be used to measure the power spectrum of solar wind fluctuations along a line in any direction with respect to the local mean magnetic field. This technique is applied to study solar wind turbulence in…

Earth and Planetary Astrophysics · Physics 2011-02-11 J. J. Podesta

Manifestations of the solar magnetic activity through periodicities of about 11 and 2 years are now clearly seen in all solar activity indices.In this paper, we add information about the mechanism driving the 2 year period by studying the…

Solar and Stellar Astrophysics · Physics 2015-06-11 R. Simoniello , K. Jain , S. C. Tripathy , S. Turck-Chieze , C. Baldner , W. Finsterle , F. Hill , M. Roth
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