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A New Formula Describing The Scaffold Structure Of Spiral Galaxies, Harry I. Ringermacher, Lawrence R. Mead
A New Formula Describing The Scaffold Structure Of Spiral Galaxies, Harry I. Ringermacher, Lawrence R. Mead
Faculty Publications
We describe a new formula capable of quantitatively characterizing the Hubble sequence of spiral galaxies including grand design and barred spirals. Special shapes such as ring galaxies with inward and outward arms are also described by the analytic continuation of the same formula. The formula is r() = A/log [B tan (/2N)]. This function intrinsically generates a bar in a continuous, fixed relationship relative to an arm of arbitrary winding sweep. A is simply a scale parameter while B, together with N, determines the spiral pitch. Roughly, greater N results in tighter winding. Greater B results in greater arm sweep …
Simple Fit Of Data Relating Supermassive Black Hole Mass To Galaxy Pitch Angle, Harry I. Ringermacher, Lawrence R. Mead
Simple Fit Of Data Relating Supermassive Black Hole Mass To Galaxy Pitch Angle, Harry I. Ringermacher, Lawrence R. Mead
Faculty Publications
Seigar et al. have recently demonstrated a new, tight correlation between galactic central supermassive black hole (BH) mass and the pitch angle of the spiral arm in disk galaxies which they attribute to other indirect correlations. They fit a double power law, governed by five parameters, to the BH mass as a function of pitch. Noting the features of their fitted curve, we show that a simple linear proportion of the BH mass to the cotangent of the pitch angle can obtain the same fit, within error. Such a direct, elegant fit may help shed light on the nature of …