Abstract
NGC4477 is a low-mass lenticular galaxy in the Virgo Cluster, residing at 100 kpc to the north of M87. Using a total of 116 ks Chandra observations, we study the interplay between its hot (~0.3 keV) gas halo and the central supermassive black hole. A possible cool core is indicated by the short cooling time of the gas at the galaxy centre. We identify a pair of symmetric cavities lying 1.1 kpc south-east and 0.9 kpc north-west of the galaxy centre with diameters of 1.3 and 0.9 kpc, respectively. We estimate that these cavities are newly formed with an age of ~4Myr. No radio emission is detected at the positions of the cavities with the existing Very Large Array data. The total energy required to produce the two cavities is ~1054 erg, at least two orders of magnitude smaller than that of typical X-ray cavities. NGC4477 is arguably far the smallest system and the only lenticular galaxy in which active galactic nuclei (AGN) X-ray cavities have been found. It falls on the scaling relation between the cavity power and the AGN radio luminosity, calibrated for groups and clusters. Our findings suggest that AGN feedback is universal among all cool-core systems. Finally, we note the presence of molecular gas in NGC4477 in the shape of a regular disc with ordered rotation, which may not be related to the feedback loop.
| Original language | English |
|---|---|
| Pages (from-to) | 4279-4286 |
| Number of pages | 8 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 480 |
| Issue number | 4 |
| DOIs | |
| State | Published - Nov 11 2018 |
Bibliographical note
Publisher Copyright:© 2018 The Author(s).
Funding
The scientific results are based on observations made by the Chandra X-ray Observatory. This work is supported by the National Science Foundation of China under grant J1210039.We thank Paul Nulsen, Ewan O'Sullivan, and Larry David for their inspiring discussions. We thank Alison Crocker for providing us the cold gas image of NGC4477 in Fig. 9. We also thank the referee for insightful comments. YL thanks Felipe Andrade-Santos and Scott Randall for helpful advice on the spectral analysis, and Zhiyuan Li for comments on the paper. YL appreciates the warm hospitality of Matthew Ashby and Jonathan McDowell during her visit to the Harvard-Smithsonian Center for Astrophysics, and acknowledges support from Top-notch Academic Programs Project of Jiangsu Higher Education Institutions
| Funders | Funder number |
|---|---|
| National Natural Science Foundation of China (NSFC) | J1210039 |
| National Natural Science Foundation of China (NSFC) |
Keywords
- Galaxies: ISM
- Galaxies: active
- Galaxies: individual: NGC 4477
- X-rays: galaxies
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science