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相关论文: A method for the estimation of p-mode parameters f…

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We present an adaptation of the rotation-corrected, m-averaged spectrum technique designed to observe low signal-to-noise-ratio, low-frequency solar p modes. The frequency shift of each of the 2l+1 m spectra of a given (n,l) multiplet is…

太阳与恒星天体物理 · 物理学 2011-02-11 D. Salabert , J. Leibacher , T. Appourchaux , F. Hill

In order to take full advantage of the long time series collected by the GONG and MDI helioseismic projects, we present here an adaptation of the rotation-corrected $m$-averaged spectrum technique in order to observe low radial-order solar…

天体物理学 · 物理学 2009-06-23 David Salabert , John W. Leibacher , Thierry Appourchaux

We introduce a new method to detect solar-like oscillations in frequency power spectra of stellar observations, under conditions of very low signal to noise. The Moving-Windowed-Power-Search, or MWPS, searches the power spectrum for…

太阳与恒星天体物理 · 物理学 2015-06-11 Mikkel N. Lund , William J. Chaplin , Hans Kjeldsen

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…

天体物理学 · 物理学 2008-11-12 D. Salabert , A. Eff-Darwich , R. Howe , S. G. Korzennik

Thanks to their high quality, new and upcoming asteroseismic observations - with CoRoT, Kepler, and from the ground... - can benefit from the experience gained with helioseismology. We focus in this paper on solar-like oscillations, for…

天体物理学 · 物理学 2008-04-02 J. Ballot , T. Appourchaux , T. Toutain , M. Guittet

The observed solar p-mode frequencies provide a powerful diagnostic of the internal structure of the Sun and permit us to test in considerable detail the physics used in the theory of stellar structure. Amongst the most commonly used…

天体物理学 · 物理学 2009-10-31 M. C. Rabello-Soares , Sarbani Basu , J. Christensen-Dalsgaard

The excitation rate P of solar p-modes is computed with a model of stochatic excitation which involves constraints on the averaged properties of the solar turbulence. These constraints are obtained from a 3D simulation. Resulting values for…

天体物理学 · 物理学 2007-05-23 R. Samadi , M. J. Goupil , Y. Lebreton , A. Nordlund , F. Baudin

We suggest a solution to an important problem of observational helioseismology of the separation of lines of solar acoustic (p) modes of low angular degree in oscillation power spectra by constructing optimal masks for Doppler images of the…

天体物理学 · 物理学 2009-10-31 T. Toutain , A. G. Kosovichev

In the case of spatially-revolved helioseismic data (such as MDI, GONG, HMI), the usual mode-fitting analysis consists of fitting the 2l+1 individual m-spectra of a given multiplet (n, l) either individually or simultaneously. Such fitting…

天体物理学 · 物理学 2008-10-13 D. Salabert , R. A. Garcia

Here we present a detailed analysis of solar acoustic mode frequencies and their rotational splittings for modes with degree up to 900. They were obtained by applying spherical harmonic decomposition to full-disk solar images observed by…

天体物理学 · 物理学 2008-08-22 M. C. Rabello-Soares , S. G. Korzennik , J. Schou

The development of space-borne missions has significantly improved the quality of the measured spectra of solar-like oscillators. Their $p$-mode line profiles can now be resolved, and the asymmetries inferred for a variety of stars other…

太阳与恒星天体物理 · 物理学 2021-01-04 J. Philidet , K. Belkacem , H. -G. Ludwig , R. Samadi , C. Barban

Recent studies have established that peaks in solar oscillation power spectra are not Lorentzian in shape, but have a distinct asymmetry. Fitting a symmetric Lorentzian profile to the peaks therefore produces a shift in frequency of the…

During the last decades, international attempts have been made to develop realistic space weather prediction tools aiming to forecast the conditions on the Sun and in the interplanetary environment. These efforts have led to the development…

Oscillations were observed across the whole solar disk using the Doppler shift and line depth of spectral lines from the CO molecule near 4666~nm with the National Solar Observatory's McMath/Pierce solar telescope. Power, coherence, and…

太阳与恒星天体物理 · 物理学 2015-05-20 Matthew Penn , Tom Schad , Erin Cox

We describe a global parametric model for the observed power spectra of solar oscillations of intermediate and low degree. A physically motivated parameterization is used as a substitute for a direct description of mode excitation and…

太阳与恒星天体物理 · 物理学 2015-06-17 Sergei V. Vorontsov , Stuart M. Jefferies

We present a new and highly efficient algorithm for computing a power spectrum made from evenly spaced data which combines the noise-reducing advantages of the weighted fit with the computational advantages of the Fast Fourier Transform…

太阳与恒星天体物理 · 物理学 2015-05-28 S. T. Fletcher , A. -M. Broomhall , W. J. Chaplin , Y. Elsworth , R. New

The characteristic of the solar acoustic spectrum is such that mode lifetimes get shorter and spatial leaks get closer in frequency as the degree of a mode increases for a given order. A direct consequence of this property is that…

天体物理学 · 物理学 2009-11-07 S. G. Korzennik , M. C. Rabello-Soares , J. Schou

We present a comprehensive study of one method for measuring various parameters of global modes of oscillation of the Sun. Using velocity data taken by the Michelson Doppler Imager (MDI), we analyze spherical harmonic degrees l <= 300. Both…

太阳与恒星天体物理 · 物理学 2015-11-18 Tim Larson , Jesper Schou

An iterative method is presented for reconstructing the height-temperature profile of the solar atmosphere above a sunspot using multi-frequency spectro-polarimetric microwave observations. It is assumed that the emission is formed…

太阳与恒星天体物理 · 物理学 2026-03-09 T. I. Kaltman , A. G. Stupishin , G. A. Makoev

We investigate the parameters of global solar p-mode oscillations, namely damping width $\Gamma$, amplitude $A$, mean squared velocity $\langle v^2\rangle$, energy $E$, and energy supply rate $\mathrm{d}E/\mathrm{d} t$, derived from two…

太阳与恒星天体物理 · 物理学 2018-10-23 René Kiefer , Rudi Komm , Frank Hill , Anne-Marie Broomhall , Markus Roth
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