GOLF instrument on board SoHO spacecraft.
The calibrated GOLF (Global Oscillations at Low Frequencies) /SoHO space observations and several derived data products are available below. They are regularly updated (last update December 2017).
Official site with mission information on the spaceborn SoHO solar observatory.
- 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 October 31, 2015 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 data (mean PM1+PM2)
Solar acoustic power spectrum from 20 years of GOLF/SoHO continuous observations.
Acoustic oscillation frequencies of the l = 0, 1, 2, and 3 modes extracted from the 365-day GOLF/SoHO spectrum calculated between 1996 April 11, and 1997 April 10.
- 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) and were updated as longer time series were available. They were extracted from one-year (365 days) GOLF time series, with a four-time overlap (91.25 days). Today, a total of 78 non-independent one-year frequency tables covering 20 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, 3, 4: respectively the year, month, and day of the starting date of each 365-day time series;
- column 5: the associated duty cycle in %;
- column 6: 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) and were updated as longer time series were available. 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 365-day GOLF frequency shifts
Temporal variability of the
Photometric activity index, Sph (in ppm), for the blue, green, and red channels of the VIRGO/SPM observations as a function
of time.
- Download the photospheric activity GOLF Svel and VIRGO/SPMs Sph
The photospheric solar activity proxies GOLF Svel and VIRGO/SPMs Sph were obtained as described in Salabert et al. (2017) based on Mathur et al. 2014. These proxies were calculated over sub series of 125 days (5xProt, with Prot = 25 days) with an overlap of a factor 8 (i.e., 15.625 days).
The VIRGO instrument is composed of three Sun photometers (SPM) at 402nm (blue channel), 500nm (green channel), and 862nm (red channel), and the Sph for the three channels are provided. The composite Sph between the green and red channels which have the closest bandwidth to Kepler observations is also provided.
Please cite Salabert et al. (2017) when publishing results using these data.
The available ASCII files contain 7 columns as following:
- column 1: Number of the analyzed 125-day sub series (non-independent sub series were analyzed as an overlap of a factor 8 was used, i.e. 15.625 days)
- column 2: Day of the first data point
- column 3: Month of the first data point
- column 4: Year of the first data points
- column 5: GOLF radial velocity index (Svel in m/s) or VIRGO/SPMs photometric index (Sph in ppm)
- column 6: Error on Svel (or Sph) index
- column 7: Duty cycle in % of each sub-series
And 2 additional columns for GOLF only:
- column 8: flag indicating if the analyzed sub series contains observations from the red-wing period (1 no / 2 yes)
- column 9: percentage (%) of measurements from the red-wing period in the analyzed sub series
