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The high-quality, full-disk helioseismic observations continuously collected by the spectrophotometer GOLF and the three photometers VIRGO/SPMs onboard the SoHO spacecraft for 17 years now (since April 11, 1996, apart from the SoHO…

太阳与恒星天体物理 · 物理学 2013-09-18 D. Salabert , R. A. Garcia , A. Jimenez

The parameters of the p-mode oscillations vary with solar activity. Such temporal variations provide insights for the study of the structural and dynamical changes occurring in the Sun's interior throughout the solar cycle. We present here…

太阳与恒星天体物理 · 物理学 2015-05-20 David Salabert , Rafael A Garcia , Pere L Palle , Antonio Jimenez

Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been…

太阳与恒星天体物理 · 物理学 2015-05-20 O. L. Creevey , D. Salabert , R. A. Garcia

The acoustic cut-off frequency -the highest frequency for acoustic solar eigenmodes- is an important parameter of the solar atmosphere as it determines the upper boundary of the p-mode resonant cavities. At frequencies beyond this value,…

太阳与恒星天体物理 · 物理学 2015-05-30 A. Jimenez , R. A. Garcia , P. L. Palle

We used long high-quality unresolved (Sun-as-a-star observations) data collected by GOLF and VIRGO instruments on board the ESA/NASA SOHO satellite to investigate the amplitude variation with solar cycle 23 in the high-frequency band (5.7 <…

太阳与恒星天体物理 · 物理学 2015-05-13 R. Simoniello , W. Finsterle , R. A. Garcia , D. Salabert , A. Jimenez

The solar brightness varies on timescales from minutes to decades. A clear identification of the physical processes behind such variations is needed for developing and improving physics-based models of solar brightness variability and…

太阳与恒星天体物理 · 物理学 2015-09-30 A. I. Shapiro , S. K. Solanki , N. A. Krivova , R. V. Tagirov , W. K. Schmutz

Using full-disk observations obtained with the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO) spacecraft, we present variations of the solar acoustic mode frequencies caused by the solar activity…

天体物理学 · 物理学 2008-11-26 M. C. Rabello-Soares , S. G. Korzennik , J. Schou

Variations of frequency separations of low-degree p-modes are studied over the solar activity cycle. The separations studied are obtained from the frequencies of low-degree p-modes of the Global Oscillation Network Group (GONG). 10.7 cm…

太阳与恒星天体物理 · 物理学 2015-05-14 Wuming Yang , Xiangcun Meng

Below the acoustic cut-off frequency, oscillations are trapped within the solar interior and become resonant. However, signatures of oscillations persist above the acoustic cut-off frequency, and these travelling waves are known as…

太阳与恒星天体物理 · 物理学 2022-03-30 K. Kosak , R. Kiefer , A. M. Broomhall

We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…

太阳与恒星天体物理 · 物理学 2023-12-20 Mackenzie A. Baird , Sushanta C. Tripathy , Kiran Jain

Solar five-minute oscillations have been detected in the power spectra of two six-day time intervals from soft X-ray measurements of the Sun observed as a star using the Extreme Ultraviolet Spectrophotometer (ESP) onboard the Solar Dynamics…

太阳与恒星天体物理 · 物理学 2015-06-12 Leonid Didkovsky , Alexander Kosovichev , Darrell Judge , Seth Wieman , Tom Woods

In this paper, we investigate the inhomogeneous spatial distribution of solar faculae. The focus is on the latitudinal and longitudinal distributions of these highly localised features covering ubiquitously the solar surface. The…

太阳与恒星天体物理 · 物理学 2018-08-22 A. Elek , N. Gyenge , M B. Korsós , R. Erdélyi

We present the power spectrum of solar irradiance during 1985 and 1987 obtained from the ACRIM project from time scales of minutes to months. At low frequency the spectra are Lorentzian. At higher frequencies they are proportional to…

天体物理学 · 物理学 2009-10-28 Jon D. Pelletier

The long and almost continuous observations by Kepler show clear evidence of a granulation background signal in a large sample of stars, which is interpreted as the surface manifestation of convection. It has been shown that its…

太阳与恒星天体物理 · 物理学 2014-10-15 T. Kallinger , J. De Ridder , S. Hekker , S. Mathur , B. Mosser , M. Gruberbauer , R. A. Garcia , C. Karoff , J. Ballot

Due to non-homogeneous mass distribution and non-uniform velocity rate inside the Sun, the solar outer shape is distorted in latitude. In this paper, we analyze the consequences of a temporal change in this figure on the luminosity. To do…

太阳与恒星天体物理 · 物理学 2011-08-31 Z. Fazel , J. P. Rozelot , S. Lefebvre , A. Ajabshirizadeh , S. Pireaux

We show that chirping gravitational waves in the LIGO frequency band $f=1 - 5000$ Hz can be gravitationally diffracted by the Sun, due to the coincidence of its Fresnel length $r_F \propto \sqrt{1\, {\rm AU}/f}$ and the solar radius…

宇宙学与河外天体物理 · 物理学 2023-07-26 Sunghoon Jung , Sungjung Kim

We analyze intermediate degree p-mode eigenfrequencies measured by GONG and MDI/SOHO over a solar cycle to study the source of their variability. We carry out a correlation analysis between the change in frequencies and several measures of…

太阳与恒星天体物理 · 物理学 2011-02-11 Kiran Jain , S. C. Tripathy , F. Hill

Starting from December 2004, a program for the monitoring of intraday variable sources at a frequency of 5 GHz was performed at the Urumqi Observatory. The analysis of the variability characteristics of the flat-spectrum radio source AO…

太阳与恒星天体物理 · 物理学 2015-05-27 N. Marchili , T. P. Krichbaum , X. Liu , H. -G. Song , J. M. Anderson , A. Witzel , J. A. Zensus

Differences between observed and theoretical eigenfrequencies of the Sun have characteristics which identify them as arising predominantly from properties of the oscillations in the vicinity of the solar surface: in the super-adiabatic,…

天体物理学 · 物理学 2007-05-23 C. S. Rosenthal , J. Christensen-Dalsgaard , A. Nordlund , R. F. Stein , R. Trampedach

The total solar irradiance (TSI) varies on timescales of minute to centuries. On short timescales it varies due to the superposition of intensity fluctuations produced by turbulent convection and acoustic oscillations. On longer scale…

太阳与恒星天体物理 · 物理学 2022-10-12 V. Penza , F. Berrilli , L. Bertello , M. Cantoresi , S. Criscuoli , P. Giobbi