Astrophysical: Galaxies

  • Publication
    Optical novae: the major class of supersoft X-ray sources in M 31
    We searched for X-ray counterparts of optical novae detected in M 31 and M 33. We combined an optical nova catalogue from the WeCAPP survey with optical novae...
  • Publication
    Optical observations of Dwingeloo 1, a nearby barred spiral galaxy behind the Milky Way
    We present new optical observations of the nearby barred spiral galaxy Dwingeloo 1 (Dw1) obtained with the Isaac Newton, William Herschel and Wise telescopes...
  • Publication
    Optical Photometry of Quasar 0957+561A, B
    Observations of the gravitational lens system 0957+561A, B in the R band are presented in this Letter. The observations, taken with the 82 cm IAC-80 telescope...
  • Publication
    Optical Properties of the Ultraluminous X-Ray Source Holmberg IX X-1 and Its Stellar Environment
    Holmberg IX X-1 is an archetypal ultraluminous X-ray source (ULX). Here we study the properties of the optical counterpart and of its stellar environment using...
  • Publication
    Optical Recombination Lines of Heavy Elements in Giant Extragalactic H II Regions
    We present high-resolution observations of the giant extragalactic H II regions NGC 604, NGC 2363, NGC 5461, and NGC 5471, based on observations taken with the...
  • Publication
    Optical spectral characterization of the gamma-ray blazars S4 0954+65, TXS 1515-273, and RX J0812.0+0237
    The study of gamma-ray blazars is usually hindered due to the lack of information on their redshifts and on their low-energy photon fields. This information is...
  • Publication
    Optical spectral characterization of the gamma-ray blazars S4 0954+65, TXS 1515-273, and RX J0812.0+0237
    The study of gamma-ray blazars is usually hindered due to the lack of information on their redshifts and on their low-energy photon fields. This information is...
  • Publication
    Optical spectral characterization of the TeV extreme blazar 2WHSP J073326.7+515354
    The emission from the relativistic jets in blazars usually outshines their host galaxies, challenging the determination of their distances and the...
  • Publication
    Optical Spectroscopic Survey of a Sample of Unidentified Fermi Objects
    We present optical spectroscopy secured at the 10 m Gran Telescopio Canarias of the counterparts of 20 extragalactic γ-ray sources detected by the Fermi...