The Black Hole in the Compact, High-Dispersion Galaxy NGC 1271

Abstract

Located in the Perseus cluster, NGC 1271 is an early-type galaxy with a small effective radius of 2.2 kpc and a large bulge stellar velocity dispersion of 276 km s −1 for its K-band luminosity of L 8.9 10 10  . We present a mass measurement for the black hole in this compact, high-dispersion galaxy using observations from the Near-infrared Integral Field Spectrometer on the Gemini North telescope assisted by laser guide star adaptive optics, large-scale integral field unit observations with PPAK at the Calar Alto Observatory, and Hubble Space Telescope WFC3 imaging observations. We are able to map out the stellar kinematics both on small spatial scales, within the black hole sphere of influence, and on large scales that extend out to four times the galaxy's effective radius. We find that the galaxy is rapidly rotating and exhibits a sharp rise in the velocity dispersion. Through the use of orbit-based stellar dynamical models, we determine that the black hole has a mass of M (3.0 ) 10 1.1 1.0 9 -+  and the H-band stellar mass-to-light ratio is 1.40 0.11 0.13 ¡ -+  (1s uncertainties). NGC 1271 occupies the sparsely populated upper end of the black hole mass distributionbut is very different from the brightest cluster galaxies (BCGs) and giant elliptical galaxies that are expected to host the most massive black holes. Interestingly, the black hole mass is an order of magnitude larger than expectations based on the galaxy's bulge luminositybut is consistent with the mass predicted using the galaxy's bulge stellar velocity dispersion. More compact, high-dispersion galaxies need to be studied using high spatial resolution observations to securely determine black hole masses, as there could be systematic differences in the black hole scaling relations between these types of galaxies and the BCGs/giant ellipticals, thereby implying different pathways for black hole and galaxy growth.

A low upper mass limit for the central black hole in the late-type galaxy NGC 4414

“…B.2 and the parameters are given in Table 2. The NIFS PSF is comparable to measurements from other papers which use laser guide star adaptive optics (Krajnović et al 2009;Walsh et al 2015). In addition, we used the narrow component of the NIFS PSF to determine the Strehl ratio which yields 30.8% (details are given in Appendix B.3).…”

Explaining the reportedly overmassive black holes in early-type galaxies with intermediate-scale discs

“…the mass of their central supermassive black hole has been reported to be significantly larger than what is expected from the galaxy's spheroid luminosity (or stellar mass). This is the case for the galaxies Mrk 1216 (for which only an upper limit on its black hole mass has been published, Yıldırım et al 2015), NGC 1271 (Walsh et al 2015b), NGC 1277(van den Bosch et al 2012Yıldırım et al 2015;Walsh et al 2015a) and NGC 1332 (Rusli et al 2011). In addition to these, the elliptical galaxy NGC 4291 has also been claimed to be a ∼3.6σ outlier above the (black hole mass)-(spheroid mass) scaling relation (Bogdán et al 2012).…”

The MASSIVE Survey. XV. A Stellar Dynamical Mass Measurement of the Supermassive Black Hole in Massive Elliptical Galaxy NGC 1453

“…These pairs of definitions are only expected to differ when there is significant contribution from the ordered flow velocity term v φ 2 . For reference, differing definitions and symbols were used in the literature, e.g., β from Thomas et al (2014), β r from Peletier et al (2007), and σ r /σ t from Walsh et al (2015) all excluded the v φ 2 term, while β rot from Krajnović et al (2018) and Thomas et al (2014) and σ r /σ t from Gebhardt et al (2003) included this term.…”