Publications

  • X-ray binary accretion states in active galactic nuclei? Sensing the accretion disc of supermassive black holes with mid-infrared nebular lines

    Accretion states, which are universally observed in stellar mass black holes in X-ray binaries, might be expected in active galactic nuclei (AGN). This is the case at low luminosities, when the jet-corona coupling dominates the energy output in both populations. Previous attempts to extend this framework to a wider AGN population have been

    Fernández-Ontiveros, Juan A. et al.

    Advertised on:

    7
    2021
  • A deep learning approach to photospheric parameters of CARMENES target stars

    In the light of more and more new instrumentation to get a deeper insight into the universe, tons of data are collected. While traditional machine-learning methods have been used in processing stellar spectral data, such large new datasets are better handled with Deep Learning (DL) techniques. In this work, we present a Deep Convolutional Neural

    Passegger, Vera Maria et al.

    Advertised on:

    3
    2021
  • A Deep Learning Approach to photospheric Parameters of CARMENES Target Stars

    We construct an individual convolutional neural network architecture for each of the four stellar parameters effective temperature (Teff), surface gravity (log g), metallicity [M/H], and rotational velocity (v sin i). The networks are trained on synthetic PHOENIX-ACES spectra, showing small training and validation errors. We apply the trained

    Passegger, Vera Maria et al.

    Advertised on:

    3
    2021
  • A tale of two stellar characterisation codes: StePar and SteParSyn

    We report on two state-of-the-art codes designed to characterise the spectra of late-type stars. STEPAR is a Python 3.X code that implements the EW method to calculate stellar atmospheric parameters (Teff, log(g), and [Fe/H]) of FGK stars. This code has already been extensively used to analyse high-resolution stellar spectra of thousands of Gaia

    Tabernero, H. M. et al.

    Advertised on:

    3
    2021
  • Giant white-light flares on fully convective stars occur at high latitudes

    In a <strong>systematic analysis of fully convective stars observed with TESS</strong>, we detected four stars that displayed giant <strong>flares that were modulated in brightness by the stars' rapid rotation</strong>. The morphology of the modulation allowed us to directly <strong>localize these flares between </strong><strong>55°</strong><strong

    Ilin, Ekaterina et al.

    Advertised on:

    3
    2021
  • Mapping stellar activity indicators across the M dwarf domain

    Despite stellar magnetic activity being present in most cool stars, its effects on spectroscopic observations are still not well understood. Several activity indicators are routinely used to identify activity-related signals in radial velocity (RV) measurements, but not all indicators trace exactly the same effects, nor are any of them always

    Lafarga, Marina et al.

    Advertised on:

    3
    2021