Abstract
ABSTRACT The Seyfert 1 galaxy, Arakelian 120, has undergone an optical flare from October 1977 to September 1978. The most rapid change in brightness detected was a change of 0.24 m in 25 days. This variation implies an upper limit on the size of the optical source region of 0.0202 pc based on light-travel-time arguments (assuming no relativistic effects). The optical variability and color variations are consistent with a composite galaxy-nonthermal central source model in which the nonthermal central source varies both in luminosity and color. A second possible interpretation is that the variations in color and brightness are due to variability in both the broad emission lines which are present and in the nonthermal continuum.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Publications of the Astronomical Society of the Pacific
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
