Related papers: Calibrating 15 years of GOLF data

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…

We analyze more than 5000 days of Sun-as-a-star radial velocity GOLF and intensity VIRGO observations to measure the visibilities of the l=0, 1, 2, and 3 modes and the m-amplitude ratios of the l=2 and 3 modes in the solar acoustic…

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 <…

The global oscillations of the Sun are investigated on the base of three independent sets of data: 1. Records of Total Solar Irradiance (TSI). 2. The average brightness of the photosphere in MDI (SOHO) and HMI (SDO) images. 3. Records of…

Sun-as-a-star observations are very important for the study of the conditions within the Sun and in particular for the deep interior where higher degree modes do not penetrate. They are also of significance in this era of dramatic advances…

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…

We analyze more than 5000 days of high-quality Sun-as-a-star, radial velocity GOLF and photometric VIRGO/SPM helioseismic observations to extract precise estimates of the visibilities of the low-degree p modes and the m-height ratios of the…

Since the detection of the asymptotic properties of the dipole gravity modes in the Sun, the quest to find the individual gravity modes has continued. A deeper analysis of the GOLF/SoHO data unveils the presence of a pattern of peaks that…

The SoHO spacecraft made astrophysicists achieve a major breakthrough in the knowledge of the Sun. In helioseismology, both GOLF and MDI experiments aboard SoHO greatly improve the accuracy of seismic data. More specifically, the detection…

All p-mode parameters vary with time as a response to the changes induced by the cyclic behavior of solar magnetic activity. After the unusual long solar-activity minimum between cycles 23 and 24, where the p-mode parameters have shown a…

We analyze Sun-as-a-star observations spanning over solar cycles 22 -- 24 from the ground-based network BiSON and solar cycles 23 -- 24 collected by the space-based VIRGO and GOLF instruments on board the {\it SoHO} satellite. Using…

From the observing campaigns of a number of helioseismic telescope networks such as the Global Oscillation Network Group (GONG) and also from the Solar Heliospheric Observatory satellite (SoHO), helioseismologists now have data on in excess…

The Global Oscillations at Low Frequencies instrument aboard the Solar and Heliospheric Observatory has provided over two decades of continuous, high-precision data, enabling detailed measurements of the Sun's oscillation frequencies. These…

The time-variable velocity fields of solar-type stars limit the precision of radial-velocity determinations of their planets' masses, obstructing detection of Earth twins. Since 2015 July we have been monitoring disc-integrated sunlight in…

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…

To better understand the influence of the activity cycle on the solar atmosphere, we report the time variation of the radius observed at 37 GHz ($\lambda$=8.1 mm) obtained by the Mets\"ahovi Radio Observatory (MRO) through Solar Cycles 22…

We report on an ongoing investigation into a seismic calibration of solar models designed for estimating the main-sequence age and a measure of the chemical abundances of the Sun. Only modes of low degree are employed, so that with…

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…

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…

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…