Analytical properties of the R1/m law
نویسندگان
چکیده
In this paper we describe some analytical properties of the R1/m law proposed by Sersic (1968) to categorize the photometric profiles of elliptical galaxies. In particular, we present the full asymptotic expansion for the dimensionless scale factor b(m) that is introduced when referring the profile to the standard effective radius. Surprisingly, our asymptotic analysis turns out to be useful even for values of m as low as unity, thus providing a unified analytical tool for observational and theoretical investigations based on the R1/m law for the entire range of interesting photometric profiles, from spiral to elliptical galaxies.
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