Observational constraints on viscosity in AGN accretion discs
نویسندگان
چکیده
منابع مشابه
Constraints on AGN accretion disc viscosity derived from continuum variability
We estimate a value of the viscosity parameter in AGN accretion discs for the PG quasar sample. We assume that optical variability on time-scales of months to years is caused by local instabilities in the inner accretion disc. Comparing the observed variability time-scales to the thermal time-scales of α-disc models we obtain constraints on the viscosity parameter for the sample. We find that, ...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1989
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/239.1.289