On the light curve of 3C 273

Abstract

view Abstract Citations (26) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the light curve of 3C 273. Fahlman, G. G. ; Ulrych, T. J. Abstract The technique of autoregressive (AR) decomposition is used to analyze the historical light curve of quasar 3C 273 on the assumption that the observed optical fluctuations are the output of a linear system whose input is shot noise. The AR representation of this random process is calculated in a way consistent with the principle of maximum entropy and employs the Akiake (1969) final-prediction error criterion for choosing the order of the process. The AR parameters are inverted to obtain the minimum-delay impulse response of the linear system, and the optimally smoothed maximum-entropy power spectrum is computed. Synthetic examples based on a previously developed shot-noise model of 3C 273 are discussed. Decomposition of the actual light curve yields no evidence for any periodic component and indicates that the optical pulse responsible for the observed variability bears a qualitative resemblence to the light curve of a Type I supernova. It is emphasized that the quasar variation is not attributed to supernovae. Publication: The Astrophysical Journal Pub Date: October 1975 DOI: 10.1086/153884 Bibcode: 1975ApJ...201..277F Keywords: Light Curve; Linear Systems; Quasars; Regression Analysis; Shot Noise; Time Series Analysis; Entropy; Graphs (Charts); Poisson Density Functions; Power Spectra; Pulse Amplitude; Supernovae; Transfer Functions; White Noise; Astrophysics full text sources ADS | data products NED (1)