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تسجيل مستخدم جديدLow-mass and High-mass Supermassive Blackholes In Radio-Loud AGNs Are Spun-up in Different Evolution Paths
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How Supermassive Blackholes (SMBHs) are spun-up is a key issue of modern astrophysics. As an extension of the study in Wang et al. (2016), we here address the issue by comparing the host galaxy properties of nearby ($z<0.05$) radio-selected Seyfert 2 galaxies. With the two-dimensional bulge+disk decompositions for the SDSS $r$-band images, we identify a dichotomy on various host galaxy properties for the radio-powerful SMBHs. By assuming the radio emission from the jet reflects a high SMBH spin, which stems from the well-known BZ mechanism of jet production, high-mass SMBHs (i.e., $M_{mathrm{BH}}>10^{7.9}M_odot$) have a preference for being spun-up in classical bulges, and low-mass SMBHs (i.e., $M_{mathrm{BH}}=10^{6-7}M_odot$) in pseudo-bulges. This dichotomy suggests and confirms that high-mass and low-mass SMBHs are spun-up in different ways, i.e., a major dry merger and a secular evolution.
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