Journal: Astrophysical Journal

  • Publication
    Asymptotic giant branch stars in NGC 6822: Probes of star formation history
    About 500 asymptotic giant branch (AGB) stars have been resolved and photometrically measured in the Local Group (LG) dwarf irregular galaxy NGC 6822. They draw...
  • Publication
    Bidimensional spectroscopy of the central kiloparsec of NGC 4151
    Sixty-one bidimensionally distributed spectra covering the circumnuclear region of NGC 4161 within a radius of about 6.5 arcsec are presented. The local...
  • Publication
    CCD monitoring of the X-ray variable quasar OX 169
    Three nights of broadband filter monitoring of the OX 169 variable X-ray quasar using a GEC-type CCD have yielded a 0.005 mag rms precision in the R band. Rapid...
  • Publication
    CCD photometry of the M87 jet
    CCD photometry of the M87 jet in the Thuan-Gunn r and g filters is presented. Accurate elliptical models of the underlying stellar emission were subtracted from...
  • Publication
    Circular polarization of the CA II H and K lines in solar quiet and active regions
    A representative set of profiles is presented for the Ca II H resonace line in Stokes V and I, for the quiet sun, plages, sunspot umbrae, and a flare, as well...
  • Publication
    Complex ionization structure and kinematics in the circumnuclear region of NGC 3227
    We present bidimensional spectroscopy of the circumnuclear region of the Seyfert galaxy NGC 3227. The physical and kinematical characteristics of the two...
  • Publication
    Constraints to the masses of brown dwarf candidates form the lithium test
    We present intermediate dispersion (0.7-2.2 A/pixel) optical spectroscopic observations aimed at applying the 'lithium test' to a sample of 10 brown dwarf...
  • Publication
    Dynamical simulations of the interacting galaxies in the NGC 520/UGC 957 system
    Numerical simulations of the interacting galaxies in the NGC 520/UGC 957 system are presented. Two sets of models were produced to investigate the postulated...
  • Publication
    Emerging flux tubes in the solar convection zone. 1: Asymmetry, tilt, and emergence latitude
    The process of emergence of magnetic flux from the depths of the convection zone to the surface is presented in the framework of self-consistent model for the...