Open AccessRadio spectra of the low‐luminosity active galactic nucleus NGC 266 at centimetre‐to‐submillimetre wavelengths
Author(s) -
Doi A.,
Kameno S.,
Inoue M.
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.09014.x
Subject(s) - physics , astrophysics , spectral index , active galactic nucleus , millimeter , centimeter , wavelength , radio telescope , astronomy , james clerk maxwell telescope , spectral line , accretion (finance) , radio astronomy , galactic center , luminosity , galaxy , star formation , optics
We report multi‐frequency and multi‐epoch radio continuum observations with multi‐spatial resolution for the low‐luminosity active galactic nucleus (LLAGN) NGC 266. In the centimetre regime, we find diffuse components with Very Large Array (VLA) observations, and a variable compact core with a rising spectrum with Very Long Baseline Array (VLBA) observations. Although the spectral index of the rising spectrum is consistent with the prediction of the simple advection‐dominated accretion flow (ADAF) model, the observed radio power is slightly high compared with that of the model prediction. A spectral break at centimetre‐to‐millimetre wavelengths is inferred from the upper limits of flux densities from Nobeyama Millimetre Array (NMA) and James Clerk Maxwell Telescope (JCMT) data at millimetre and submillimetre wavelengths, respectively. More complicated considerations are required for the theoretical model to interpret such observed radio properties.