@article{c9726e49874248b8a8511d715ea8655d,
title = "Probing the Low-Mass End of the Black Hole Mass Function via a Study of Faint Local Spiral Galaxies",
abstract = "We present an analysis of the pitch angle distribution function (PADF) for nearby galaxies and its resulting black hole mass function (BHMF) via the well-known relationship between pitch angle and black hole mass. Our sample consists of a subset of 74 spiral galaxies from the Carnegie-Irvine Galaxy Survey with absolute B-band magnitude (Formula presented.) mag and luminosity distance (Formula presented.) Mpc, which is an extension of a complementary set of 140 more luminous ((Formula presented.) mag) late-type galaxies. We find the PADFs of the two samples are, somewhat surprisingly, not strongly dissimilar; a result that may hold important implications for spiral formation theories. Our data show a distinct bimodal population manifest in the pitch angles of the Sa–Sc types and separately the Scd–Sm types, with Sa–Sc types having tighter spiral arms on average. Importantly, we uncover a distinct bifurcation of the BHMF, such that the Sa–Sc galaxies typically host so-called “supermassive” black holes ((Formula presented.)), whereas Scd–Sm galaxies accordingly harbor black holes that are “less-than-supermassive” ((Formula presented.)). It is amongst this latter population of galaxies where we expect fruitful bounties of elusive intermediate-mass black holes (IMBHs), through which a better understanding will help form more precise benchmarks for future generations of gravitational wave detectors.",
keywords = "black hole physics, galaxies: spiral, galaxies: statistics, galaxies: structure",
author = "Fusco, {Michael S.} and Davis, {Benjamin L.} and Julia Kennefick and Daniel Kennefick and Seigar, {Marc S.}",
note = "Funding Information: Our data sample and basic properties are derived from the CGS []. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. The data products presented in this study are available on request from the corresponding author. Note that unfortunately, this project suffered a significant loss of ancillary data. As a result, all of the metadata related to the pitch angle measurements (e.g., the number of spiral arms, deprojection parameters, pitch angles as a function of radius, auxiliary post-processing files and records, etc.), and reported throughout this paper in aggregate, is now lost for all of the galaxies in this study. However, these metadata do not impact the main topic of this paper. Acknowledgments Funding Information: This research was funded by a grant from the Arkansas Space Grant Consortium. The Australian Research Council{\textquoteright}s funding scheme DP17012923 supported this research. Parts of this research were conducted by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav), through project number CE170100004. This material is based upon work supported by, and the APC was funded by, Tamkeen under the NYU Abu Dhabi Research Institute grant CAP3. Publisher Copyright: {\textcopyright} 2022 by the authors.",
year = "2022",
month = dec,
doi = "10.3390/universe8120649",
language = "English (US)",
volume = "8",
journal = "Universe",
issn = "2218-1997",
publisher = "Multidisciplinary Digital Publishing Institute",
number = "12",
}