English
Related papers

Related papers: The solar internal rotation from GOLF splittings

200 papers

Accurate determination of the rotation rate in the radiative zone of the sun from helioseismic observations requires rotational frequency splittings of exceptional quality as well as reliable inversion techniques. We present here inferences…

Astrophysics · Physics 2009-11-13 A. Eff-Darwich , S. G. Korzennik , S. J. Jimenez-Reyes , R. A. Garcia

From the analysis of low-order GOLF+MDI sectoral modes and LOWL data (l > 3), we derive the solar radial rotation profile assuming no latitudinal dependance in the solar core. These low-order acoustic modes contain the most statistically…

Astrophysics · Physics 2009-11-10 S. Couvidat , R. A. Garcia , S. Turck-Chieze , T. Corbard , C. J. Henney , S. Jimenez-Reyes

We used the m-averaged spectrum technique ("collapsogram") to extract the low-frequency solar p-mode parameters of low- and intermediate-angular degrees (l \leq 35) in long time series of GONG and MDI observations. Rotational splittings and…

Astrophysics · Physics 2008-11-12 D. Salabert , A. Eff-Darwich , R. Howe , S. G. Korzennik

Frequency and rotational splittings of the solar f-modes are estimated from the GONG data. Contrary to earlier observations the frequencies of f-modes are found to be close to the theoretically computed values for a standard solar model.…

Astrophysics · Physics 2008-11-26 H. M. Antia

The solar rotation profile is well constrained down to about 0.25 R thanks to the study of acoustic modes. Since the radius of the inner turning point of a resonant acoustic mode is inversely proportional to the ratio of its frequency to…

Astrophysics · Physics 2008-04-01 R. A. Garcia , S. Mathur , J. Ballot , A. Eff-Darwich , S. J. Jimenez-Reyes , S. G. Korzennik

The dynamics of the solar radiative interior are still poorly constrained by comparison to the convective zone. This disparity is even more marked when we attempt to derive meaningful temporal variations. Many data sets contain a small…

Solar and Stellar Astrophysics · Physics 2015-06-05 Antonio Eff-Darwich , Sylain G. Korzennik

The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster…

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

We present results on variation in rotation rate in the upper convection zone using data from GONG and MDI/SOHO covering a period of more than four years. We find that the first few odd-order splitting coefficients vary systematically with…

Astrophysics · Physics 2007-05-23 Kiran Jain , S. C. Tripathy , A. Bhatnagar

Solar magnetism is measured with different indexes: for instance the MPSI and the MWSI, number of sunspots, radio flux at 10.7 cm, Ca II K, Mg II K, EUV, He I or L_alpha. Bachmann & White (1994) had compared these indicators of the solar…

Astrophysics · Physics 2008-10-13 S. Mathur , S. J. Jimenez-Reyes , R. A. Garcia

Fossat et al. (2017) recently reported detecting rotational splitting of g modes indirectly via the interaction with p modes observed directly by the GOLF instrument on SOHO. They concluded that the core of the Sun is rotating 3:8 ? 0:1…

Solar and Stellar Astrophysics · Physics 2019-05-29 P. H. Scherrer , D. O. Gough

Meridional flow is thought to play a very important role in the dynamics of the solar convection zone; however, because of its relatively small amplitude, precisely measuring it poses a significant challenge. Here we present a complete…

Solar and Stellar Astrophysics · Physics 2015-06-02 J. Jackiewicz , A. Serebryanskiy , S. Kholikov

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.…

We report our first results on comparing the variations of the solar internal rotation with solar activity, as predicted by non-linear solar dynamo modelling, with helioseismic measurements using the SOHO MDI data.

Astrophysics · Physics 2007-05-23 S. Vorontsov , R. Tavakol , E. Covas , D. Moss

The GOLFNG (Global Oscillations at Low Frequency New Generation) instrument is devoted to the search for solar gravity and acoustic modes, and also chromospheric modes from space. This instrument which is a successor to GOLF/SOHO will…

We present solar low-degree rotational splitting values based on a new analysis of Sun-as-a-star observations from the Birmingham Solar Oscillations Network, covering a 16,425-day period from 1976 December 31--2021 December 20 with a duty…

Solar and Stellar Astrophysics · Physics 2023-09-07 Rachel Howe , W. J. Chaplin , Y. P. Elsworth , S. J. Hale , M. B. Nielsen

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

Frequency splitting coefficients from Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI) observations covering the period 1995--2001 are used to study temporal variations in the solar rotation rate at high latitudes.…

Astrophysics · Physics 2009-11-07 H. M. Antia , Sarbani Basu

The GOLF resonant scattering spectrophotometer aboard SoHO has now provided 15 years of continuous high precision Sun-as-a-star radial-velocity measurements. This length of time series provides very high resolution in the frequency domain…

Solar and Stellar Astrophysics · Physics 2011-10-04 Guy R. Davies , Rafael A. García

A new set of accurately measured frequencies of solar oscillations are used to infer the rotation rate inside the Sun, as a function of radial distance as well as latitude. We have adopted a regularized least squares technique with…

Astrophysics · Physics 2009-10-30 H. M. Antia , Sarbani Basu , S. M. Chitre

Ring diagram analysis of solar oscillation power spectra obtained from MDI data is carried out to study the velocity fields in the outer part of the solar convection zone. The three dimensional power spectra are fitted to a model which has…

Astrophysics · Physics 2009-10-30 Sarbani Basu , H. M. Antia , S. C. Tripathy
‹ Prev 1 2 3 10 Next ›