Gammie, CharlesNarayan, RameshBlandford, Roger2019-09-221999Gammie, Charles F., Ramesh Narayan, and Roger Blandford. 1999. “What Is the Accretion Rate in NGC 4258?” The Astrophysical Journal 516 (1): 177–86. https://doi.org/10.1086/307089.0004-637X1538-4357http://nrs.harvard.edu/urn-3:HUL.InstRepos:41384922We estimate the accretion rate (M) over dot onto the black hole in the nucleus of NGC 4258. The result is model dependent. We find that a thin disk that is flat out to greater than or equal to 2 x 10(3) GM/c(2) (M = black hole mass) and that has inclination equal to that of the masing disk must have (M) over dot similar or equal to 0.01 M-. yr(-1) for consistency with near-infrared data. A thin disk that is warped at similar to 10(3) GM/c(2) requires (M) over dot greater than or similar to 1.5 x 10(-4) M-. yr(-1) for consistency with near-infrared data. Reasonable warp models and the near-infrared data are not consistent with (M) over dot as low as the 7 x 10(-5) alpha M-. yr(-1) proposed by Neufeld & Maloney. An advection-dominated flow model combined with the X-ray data implies (M) over dot similar or equal to 0.01 M-. yr(-1). Consistency with a tight 22 GHz upper limit on the flux from the central source requires a transition radius of similar to(10-100)GM/c(2), although the 22 GHz upper limit may be relaxed by appeal to free-free absorption. Physical conditions in the observed VLBI jet features can also be related to conditions in the inner accretion how. We conclude with a list of observations that might further constrain (M) over dot.en-USJournal Article2019-09-2210.1086/307089