Observations of the γ-ray-emitting narrow-line Seyfert 1, SBS 0846+513, and its host galaxy

Abstract

The γ-ray emitting galaxy SBS 0846 + 513 has been classified as a Narrow-Line Seyfert 1 (NLS1) from its spectroscopy, and on that basis would be thought likely to have a small central black hole hosted in a spiral galaxy. But very few of the γ-ray NLS1 have high-resolution imaging of their hosts, so it is unknown how the morphology expectation holds up for the γ-emitting class. We have observed this galaxy in the J-band with the Large Binocular Telescope’s LUCI1 camera and the ARGOS adaptive optics system. We estimate its black hole mass to lie between $4.2\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 9.7\times 10^7$, using the correlation with bulge luminosity, or $1.9\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 2.4\times 10^7$ using the correlation with Sérsic index. Our favoured estimate is 4.2 × 107M⊙, putting its mass at the high end of the NLS1 range in general but consistent with others that are γ-ray emitters. These estimates are independent of the Broad Line Region viewing geometry and avoid any underestimates due to looking down the jet axis. Its host shows evidence of a bulge + disc structure, from the isophote shape and residual structure in the nuclear-subtracted image. This supports the idea that γ-ray NLS1 may be spiral galaxies, like their non-jetted counterparts.

Narrow-Line Seyfert 1 Galaxies With Absorbed Jets–Insights From Radio Spectral Index Maps

“…In this scenario, the real central black holes masses can be considerably higher than what is derived from the BLR emission line properties, and NLS1s would be similar to BLS1s and other broad-line AGN (Decarli et al, 2008). However, inclination-independent observational properties of NLS1s, such as their host galaxy morphologies (e.g., Krongold et al, 2001;Deo et al, 2006;Antón et al, 2008;Kotilainen et al, 2016;Järvelä et al, 2018;Berton et al, 2019;Olguín-Iglesias et al, 2020;Hamilton et al, 2021, but see D'Ammando et al, 2017D'Ammando et al, 2018), and their different large-scale environments compared to BLS1s (Järvelä et al, 2017) indicate that the black hole masses should be genuinely low. Detailed studies of some individuals, using, for example, reverberation mapping, support this hypothesis (Du et al, 2014;Wang et al, 2016;Du et al, 2018;Berton et al, 2021), but more such studies are required to draw any definite conclusions.…”

Narrow-line Seyfert 1 galaxies with absorbed jets -- insights from radio spectral index maps

“…In this scenario, the real central black holes masses can be considerably higher than what is derived from the BLR emission line properties, and NLS1s would be similar to BLS1s and other broad-line AGN (Decarli et al, 2008). However, inclinationindependent observational properties of NLS1s, such as their host galaxy morphologies (e.g., Krongold et al, 2001;Deo et al, 2006;Antón et al, 2008;Kotilainen et al, 2016;Järvelä et al, 2018;Berton et al, 2019;Olguín-Iglesias et al, 2020;Hamilton et al, 2021, but see D'Ammando et al, 2017, and their different large-scale environments compared to BLS1s (Järvelä et al, 2017) indicate that the black hole masses should be genuinely low. Detailed studies of some individuals, using, for example, reverberation mapping, support this hypothesis (Du et al, 2014;Wang et al, 2016;Du et al, 2018;Berton et al, 2021), but more such studies are required to draw any definite conclusions.…”

Peaked sources and narrow‐line Seyfert 1s: A love story

“…A potential issue with this unification is that, while jetted NLS1s tend to be harbored in spiral galaxies (Berton et al 2019; Hamilton et al 2021; Järvelä et al 2018; Kotilainen et al 2016; Olguín‐Iglesias et al 2020), PS are usually hosted by ellipticals (O'Dea & Saikia 2021). However, in general, HERG‐like PS tend to have bluer colors than LERG, possibly pointing toward a more gas‐rich host (Heckman & Best 2014).…”