Updating the (supermassive black hole mass)–(spiral arm pitch angle) relation: a strong correlation for galaxies with pseudobulges

Abstract

We have conducted an image analysis of the (current) full sample of 44 spiral galaxies with directly measured supermassive black hole (SMBH) masses, M BH , to determine each galaxy's logarithmic spiral arm pitch angle, φ. For predicting black hole masses, we have derived the relation:The total root mean square scatter associated with this relation is 0.43 dex in the log M BH direction, with an intrinsic scatter of 0.33 ± 0.08 dex. The M BH -φ relation is therefore at least as accurate at predicting SMBH masses in spiral galaxies as the other known relations. By definition, the existence of an M BH -φ relation demands that the SMBH mass must correlate with the galaxy discs in some manner. Moreover, with the majority of our sample (37 of 44) classified in the literature as having a pseudobulge morphology, we additionally reveal that the SMBH mass correlates with the largescale spiral pattern and thus the discs of galaxies hosting pseudobulges. Furthermore, given that the M BH -φ relation is capable of estimating black hole masses in bulgeless spiral galaxies, it therefore has great promise for predicting which galaxies may harbour intermediate-mass black holes (IMBHs, M BH < 10 5 M ). Extrapolating from the current relation, we predict that galaxies with |φ| ≥ 26. • 7 should possess IMBHs.

A multiwavelength study of spiral structure in galaxies. I. General characteristics in the optical

“…If we exclude the Kennicutt's sample from the consideration, the average difference in the pitch angles between the remaining sources is 13 ± 14.6% of the average pitch angle calculated for these sources; if we compare the Kennictutt's sample alone with the other sources (by pairs), this turns out to be −19 ± 51%, Figure 13. Correlation between the pitch angle and Hubble stage for different results taken from the literature: Ma (2001), Davis et al (2017), Berrier et al (2013), Yu & Ho (2019), Savchenko & Reshetnikov (2013), Kennicutt (1981), and this work. with many early-type spirals having a too small pitch angle as compared to the other sources, see Fig.…”

Revealing Hidden Substructures in the MBH–σ Diagram, and Refining the Bend in the L–σ Relation

“…Labeled data-points in the left-hand panel represent all the excluded galaxies except for IC 1481 and NGC 6926, which cannot be included as they have no reliable σ measurements (see Section 3.1). The blue squares in the left-hand panel represent the galaxies which are alleged to contain pseudobulges by Kormendy & Ho (2013), Saglia et al (2016), and the references mentioned in Table 1 of Davis et al (2017). This plot suggests that pseudobulges do follow the MBH -σ relation similar to classical bulges.…”

“…In the left-hand panel of Figure 2, we have additionally highlighted galaxies alleged to have pseudo-bulges by Kormendy & Ho (2013), Saglia et al (2016), and a few additional studies mentioned in Davis et al (2017, their Table 1). These pseudo-bulges appear to follow the M BH -σ relation (see Figure 2); they are distributed about the best-fit (green) line, though with slightly more scatter than that of galaxies hosting classical bulges.…”

“…ofDavis et al (2017). NGC 0613, NGC 1365, NGC 1566, and NGC 1672 are claimed to have pseudo-bulges byCombes et al (2019).…”

The Most Ancient Spiral Galaxy: A 2.6-Gyr-old Disk with a Tranquil Velocity Field

“…Spiral arms play an active role in driving the radial and azimuthal mixing of the metals, redistributing angular momentum, and smoothing out small-scale mass distributions (e.g., Sellwood & Binney 2002;Sellwood 2014;Grand et al 2015Grand et al , 2016. The number and pitch angle of spiral arms are strongly correlated with the mass distribution of the disk and can be a powerful tool to constrain the bulge and black hole masses (Athanassoula et al 1987;Kennicutt 1981;Elmegreen & Elmegreen 1990;Berrier et al 2013;Dobbs & Baba 2014;Seigar et al 2014;Davis et al 2015Davis et al , 2017. The onset of spiral structures offers crucial insights into the origin of the Hubble sequence (Driver et al 1998; Email: tiantianyuan@swin.edu.au * ASTRO 3D Fellow Cen 2014; Genel et al 2015).…”