Exoplanets can be detected with various observational techniques. Among them, radial
velocity (RV) has the key advantages of revealing the architecture of planetary systems and …

Aims. Even the most precise radial-velocity instruments gather high-resolution spectra that
present systematic errors that a data reduction pipeline cannot identify and correct for …

Context. A challenge with radial-velocity (RV) data is disentangling the origin of signals
either due to a planetary companion or to stellar activity. In fact, the existence of a planetary …

We present an analysis of Sun-as-a-star observations from four different high-resolution,
stabilized spectrographs—HARPS, HARPS-N, EXPRES, and NEID. With simultaneous …

Context. Radial velocities (RVs) measured from high-resolution stellar spectra are routinely
used to detect and characterise orbiting exoplanet companions. The different lines present …

In our former paper I, we showed on the Sun that different active regions possess unique
intensity profiles on the Ca ii H & K lines. We now extend the analysis by showing how those …

In the search for planets orbiting distant stars, the presence of stellar activity in the
atmospheres of observed stars can obscure the radial velocity signal used to detect such …

We present a deep learning–based approach for measuring small planetary radial velocities
(RVs) in the presence of stellar variability. We use neural networks to reduce stellar RV jitter …

Context. A challenge with radial-velocity (RV) data is disentangling the origin of signals
either due to a planetary companion or to stellar activity. In fact, the existence of a planetary …

The past several decades have seen an explosion in humanity's knowledge about the
existence of distant worlds. Thousands of exoplanets have been now been discovered …