Journal: The Astrophysical Journal

  • Publication
    Optical Linear Polarization of Late M and L Type Dwarfs
    We report on the linear polarimetric observations in the Johnson I-band filter of 44 ultracool dwarfs with spectral types between M6 and L7.5, corresponding to...
  • Publication
    Optical Microvariability in Quasars: Spectral Variability
    We present a method that we developed to discern where the optical microvariability (OM) in quasars originates: in the accretion disk (related to thermal...
  • Publication
    Optical Observations of Psr J2021+3651 in the Dragonfly Nebula With the GTC
    PSR J2021+3651 is a 17 kyr old rotation powered pulsar detected in the radio, X-rays, and γ-rays. It powers a torus-like pulsar wind nebula with jets, dubbed...
  • Publication
    Optical Observations Reveal Strong Evidence for High-energy Neutrino Progenitor
    We present the earliest astronomical observation of a high-energy neutrino error box of which the variability was discovered after high-energy-neutrino...
  • 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 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...
  • Publication
    Optical Spectroscopic Survey of a Sample of Unidentified Fermi Objects: II
    We report on optical spectroscopy obtained at the 10.4 m Gran Telescopio Canarias of 28 Fermi γ-ray sources that completes the study of a sample of 60 targets...
  • Publication
    Optical Tomography of a Sunspot. II. Vector Magnetic Field and Temperature Stratification
    An observational determination of the three-dimensional magnetic and thermal structure of a sunspot is presented. It has been obtained through the application...