Presentation #403.01 in the session Radial Velocity 2.
Radial velocity (RV) measurements are crucial to determine the masses of small exoplanets and investigate the architecture of planetary systems with non-transiting planets. To push the RV exoplanet detection threshold, it is vital to find more reliable RV extraction methods. In this talk I will present the Multi-Mask Least-Squares Deconvolution (MM-LSD) RV extraction pipeline, which I have recently resubmitted to the MNRAS journal after positive referee comments. This pipeline extracts the RV from two-dimensional echelle-order spectra using LSD with multiple tailored spectral line masks after continuum normalisation and telluric absorption line correction. The MM-LSD pipeline was tested on HARPS-N data for the Sun and selected well-observed FGK stars with 5.7 < Vmag < 12.6. For stars with median signal-to-noise ratio above 100, the pipeline delivered RV time series with on average 12 per cent lower scatter as compared to the standard HARPS-N RV extraction pipeline based on the Cross-Correlation Function technique. I will show how using LSD with multiple masks removes the necessity to optimise any parameters and provides precise RVs while retaining the planetary signal. Furthermore, I will outline how the pipeline can be extended to extract a proxy for the hemispherically-averaged stellar magnetic flux. The latter is known to correlate with solar RV variations and is thus a promising way forward to disentangle stellar and planetary signals in RV data and uncover the population of Earth analogues.