The Spitzer/IRAC view of black hole-bulge scaling relations

作者：Sani E^*; Marconi A; Hunt L K; Risaliti G

来源：Monthly Notices of the Royal Astronomical Society, 2011, 413(2): 1479-1494.

DOI：10.1111/j.1365-2966.2011.18229.x

• black hole physics
• galaxies: bulges
• galaxies: fundamental parameters
• galaxies: nuclei
• galaxies: photometry
• infrared: galaxies

We present a mid-infrared investigation of the scaling relations between supermassive black hole masses (M-BH) and the structural parameters of the host spheroids in local galaxies. This work is based on 2D bulge-disc decompositions of Spitzer/IRAC 3.6 mu m images of 57 galaxies with M-BH estimates. We first verify the accuracy of our decomposition by examining the Fundamental Plane (FP) of spheroids at 3.6 mu m. Our estimates of effective radii (R-e) and average surface brightnesses, combined with velocity dispersions from the literature, define a FP relation consistent with previous determinations but doubling the observed range in R-e. None of our galaxies is an outlier of the FP, demonstrating the accuracy of our bulge-disc decomposition which also allows us to independently identify pseudo-bulges in our sample. We calibrate M/L at 3.6 mu m by using the tight M-dyn-L-bul relation (similar to 0.1 dex intrinsic dispersion) and find that no colour corrections are required to estimate the stellar mass. The 3.6 mu m luminosity is thus the best tracer of stellar mass yet studied. We then explore the connection between M-BH and bulge structural parameters (luminosity, mass, effective radius). We find tight correlations of M-BH with both 3.6 mu m bulge luminosity and dynamical mass (M-BH/M-dyn similar to 1/1000), with intrinsic dispersions of similar to 0.35 dex, similar to the M-BH-Sigma relation. Our results are consistent with previous determinations at shorter wavelengths. By using our calibrated M/L, we rescale M-BH-L-bul to obtain the M-BH-M-star relation, which can be used as the local reference for high-z studies which probe the cosmic evolution of M-BH-galaxy relations and where the stellar mass is inferred directly from luminosity measurements. The analysis of pseudo-bulges shows that four out of nine lie on the scaling relations within the observed scatter, while those with small M-BH are significantly displaced. We explore the different origins for such behaviour while considering the possibility of nuclear morphological components not reproduced by our 2D decomposition.

• 出版日期2011-5