Astrophysical: BL Lacertae objects

  • Publication
    A turned-over optical spectrum of OJ287 during the 1989 minimum
    Optical and radio data from the 1989 minimum are analyzed to examine the implications of the light curves for the spectrum. The optical spectrum increases...
  • Publication
    An intermittent extreme BL Lac: MWL study of 1ES 2344+514 in an enhanced state
    Extreme high-frequency BL Lacs (EHBL) feature their synchrotron peak of the broad-band spectral energy distribution (SED) at ν s ≥ 10 17 Hz. The BL Lac object...
  • Publication
    An interpretation of the lightcurve of BL Lac.
    Extensive monitoring is now available for a good sample of the brighter quasars and BL Lacs. In some cases, lightcurves are well enough sampled to permit...
  • Publication
    Are high polarization quasars and BL Lacertae objects really different? A study of the optical spectral properties.
    The continuum and emission lines properties of a sample of 73 blazars is studied, investigating differences and similarities among normal low-polarization...
  • News
    Astronomers discover rapid oscillations in the light of a blazar
    The international collaboration Whole Earth Blazar Telescope (WEBT), in which researchers from the Instituto de Astrofísica de Canarias (IAC) participate, has...
  • Publication
    BL Lac nuclei in elliptical galaxies
    Orientation effects are believed to be important in sources which harbor relativistic jets in their nuclei. BL Lac type objects are interpreted as a type of...
  • Publication
    Broad-band continuum and line emission of the gamma-ray blazar PKS 0537-441
    PKS 0537-441, a bright gamma -ray emitting blazar, was observed at radio, optical, UV and X-ray frequencies during various EGRET pointings, often quasi...
  • Publication
    Broadband characterisation of the very intense TeV flares of the blazar 1ES 1959+650 in 2016
    1ES 1959+650 is a bright TeV high-frequency-peaked BL Lac object exhibiting interesting features like "orphan" TeV flares and broad emission in the high-energy...
  • Publication
    CCD monitoring of quasars and BL Lacertae objects
    Johnson B CCD photometry of quasars and other active nuclei were obtained with the 1-m and 2.5-m reflectors of the Roque de los Muchachos Observatory in the...