Institute of research into the fundamental laws of the Universe

GOLF (Global Oscillations at Low Frequencies) is a French-Spanish helioseismic instrument which measures the solar global oscillation modes by observing the Sun as a star. This resonance spectrometer measures the Doppler velocity between the satellite and the Sun in the sodium absorption line. We detect the most penetrating modes: radial modes, monopole and dipole modes ... These modes are rich with information on the nuclear region of the Sun. This instrument aims to test the stellar modeling in the first phase of development by introducing missing dynamic phenomena of classical stellar evolution.

 

	Seismology: introduction
	Scientific objectives
	Operation
	Features and performances
	Others: statut, collaborations...
	Publications
	Data portal

 

• Download the GOLF data

The GOLF velocity time series were obtained following Garcia et al. (2005). Download the GOLF data from April 11, 1996 to December 31, 2013 below. Data from both PMs (PM1 and PM2) are available, as well as the mean of the two PMs. The temporal cadence of the time series is of 60 seconds and the starting date on April 11, 1996. The duty cycle is of 96%.

Please cite Garcia et al. (2005) when publishing results using these data.

Also use the following in your acknowledgements in publication: "The GOLF instrument onboard SoHO is a cooperative effort of scientists, engineers, and technicians, to whom we are indebted. SoHO is a project of international collaboration between ESA and NASA."

 

• Download the GOLF low-degree acoustic frequencies

The GOLF frequencies provided here are part of the online material of the paper Salabert et al. (2015). They were extracted from one-year (365 days) GOLF time series, with a four-time overlap (91.25 days). A total of 69 non-independent one-year frequency tables covering 18 years of GOLF observations are then available below. The zipped ascii files contain [radial order, angular degree, frequency in μHz, error_on_frequency in μHz]. It contains as well an .info file with:

- column 1: the series index associated to the frequency table;

- column 2: the Julian Date of the starting date of each 365-day time series;

- column 3: the associated duty cycle in %;

- column 4: the corresponding radio flux averaged over the same 365-day periods.

Please cite Garcia et al. (2005) and Salabert et al. (2015) when publishing results using these data.

Also use the following in your acknowledgements in publication: "The GOLF instrument onboard SoHO is a cooperative effort of scientists, engineers, and technicians, to whom we are indebted. SoHO is a project of international collaboration between ESA and NASA."

 

• Download the GOLF frequency shifts

The GOLF frequency shifts provided here were obtained and analyzed in Salabert et al. (2015). They were extracted from one-year (365 days) GOLF time series, with a four-time overlap (91.25 days). They were calculated for 4 different frequency ranges: [1800-3790μHz]; the low-frequency range [1800-2450μHz]; the mid-frequency range [2450-3110μHz]; and the high-frequency range [3110-3790μHz]. Oscillation modes from each frequency range are sensitive to different layers in the solar sub-surface interior. The frequency shifts of modes at individual angular degree l=0, l=1, and l=2 are provided, as well as the mean frequency shifts for . We note that we did not use the l=3 mode because of its lower signal-to-noise ratio over most of the oscillation frequency range. However, we provide in the corresponding table the l=3 frequency shifts for the range [2450-3110muHz] as their SNR is sufficient enough to give realiable results.

The zipped ascii files contain:

[year, month, day, fshift_l0, e_fshift_l0, fshift_l1, e_fshift_l1, fshift_l2, e_fshift_l2 {, fshift_l3, e_fshift_l3}, radio_flux].

The frequency shifts and their 1σ uncertainties are given in nHz.

Please cite  Salabert et al. (2015) when publishing results using these data.

Also use the following in your acknowledgements in publication: "The GOLF instrument onboard SoHO is a cooperative effort of scientists, engineers, and technicians, to whom we are indebted. SoHO is a project of international collaboration between ESA and NASA."

 

Download the GOLF data (mean PM1+PM2)

Download the GOLF PM1 data

Download the GOLF PM2 data

Download the 365-day GOLF frequencies

Download the 365-day GOLF frequency shifts

 

The photometric VIRGO/SPMs data are also available here.

 

Contacts :   , ,

[ Retour | Principe | Science | Caractéristiques | Informations]

 

  voir aussi la fiche Dapnia et le projet