Kavli Affiliate: Feng Yuan
| First 5 Authors: Fangzheng Shi, Feng Yuan, Zhiyuan Li, Zhao Su, Suoqing Ji
| Summary:
Supermassive black holes in galaxies spend majority of their lifetime in the
low-luminosity regime, powered by hot accretion flow. Strong winds launched
from the hot accretion flow have the potential to play an important role in
active galactic nuclei (AGN) feedback. Direct observational evidence for these
hot winds with temperature around 10 keV, has been obtained through the
detection of highly ionized iron emission lines with Doppler shifts in two
prototypical low-luminosity AGNs, namely M81* and NGC 7213. In this work, we
further identify blueshifted H-like O/Ne emission lines in the soft X-ray
spectra of these two sources. These lines are interpreted to be associated with
additional outflowing components possessing velocity around several $10^3$ km/s
and lower temperature (~0.2-0.4 keV). Blue-shifted velocity and the X-ray
intensity of these additional outflowing components are hard to be explained by
previously detected hot wind freely propagating to larger radii. Through
detailed numerical simulations, we find the newly detected blue-shifted
emission lines would come from circumnuclear gas shock-heated by the hot wind
instead. Hot wind can provide larger ram pressure force on the clumpy
circumnuclear gas than the gravitational force from central black hole,
effectively impeding the black hole accretion of gas. Our results provide
strong evidences for the energy and momentum feedback by the hot AGN wind.
| Search Query: ArXiv Query: search_query=au:”Feng Yuan”&id_list=&start=0&max_results=3