Physical environment in the nucleus of Centaurus A (NGC 5128)

Journal Article · Sun Jun 01 04:00:00 EDT 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158009· OSTI ID:5097079

Beall, J H; Rose, W K

A model is proposed for the radio and X-ray variability of the nucleus of Centaurus A in which an adiabatically expanding plasma containing a power law distribution of relativistic electrons produces the radio flux by synchrotron emission, and the X-ray flux by inverse Compton scattering of an ambient distribution of thermal photons. The variability of Centaurus A is shown to be consistent with the expansion of an initially opaque, hot (10/sup 3/--10/sup 4/ K) plasma which eventually becomes optically thin. Radio flares without corresponding X-ray flares are possible in this model because the plasma density decreases during the expansion, allowing radio radiation previously absorbed or suppressed to be observed. Some consequences of the model for the physical environment in galactic nuclei are discussed.

• Research Organization: Department of Physics and Astronomy, University of Maryland, College Park
• OSTI ID: 5097079
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 238:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
640105 -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BASIC INTERACTIONS
BREMSSTRAHLUNG
COMPTON EFFECT
COSMIC RADIO SOURCES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
EMISSIVITY
GALAXIES
GALAXY NUCLEI
INTERACTIONS
IONIZATION
IONIZING RADIATIONS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLASMA
RADIATION FLUX
RADIATIONS
RADIO GALAXIES
RADIOWAVE RADIATION
RECOMBINATION
SCATTERING
SURFACE PROPERTIES
SYNCHROTRON RADIATION
VARIATIONS
X RADIATION
X-RAY GALAXIES