activity
20242026
collaborators

5 papers

astro-ph.GA2026

AGN Fueling and Radio Jet Evolution in the Galaxy Group NGC 5044 revealed by VLBA HI Absorption and Proper-Motion Radio Observations

Francesco Ubertosi, Ewan O'Sullivan, Gerrit Schellenberger +8

The role of cooling gas in triggering active galactic nucleus (AGN) feedback in the centers of galaxy groups and clusters remains a key open question. NGC 5044, the X-ray brightest…

astro-ph.GA2026

A MeerKAT view of the Neutral Atomic Gas in Stephan's Quintet

K. Rajpurohit, E. O'Sullivan, G. Schellenberger +7

We present new MeerKAT 21cm spectral line observations of the neutral hydrogen gas in the compact galaxy group Stephan's Quintet (HCG 92). These data provide a significantly improv…

astro-ph.GA2025

Multiphase gas offsets in the atmospheres of central galaxies and their consequences for SMBH activation I. The hot and warm ionized gas phases

Francesco Ubertosi, Fabrizio Brighenti, Ewan O'Sullivan +10

We investigate the spatial relationships between multi-phase gas components and supermassive black hole (SMBH) activity in a sample of 25 cool core galaxy groups and clusters. Usin…

astro-ph.GA2025

Revisiting the Group-Dominant Elliptical NGC 5044 in the Radio Band: Continuum Emission and Detection of HI Absorption

Kamlesh Rajpurohit, Tirna Deb, Konstantinos Kolokythas +9

We present new MeerKAT L-band (continuum and HI) and upgraded Giant Metrewave Radio Telescope (300-850 MHz) observations of the archetypal cool-core group-dominant early-type galax…

astro-ph.GA2024

HCG 57: Evidence for shock-heated intergalactic gas from X-rays and optical emission line spectroscopy

Ewan O'Sullivan, P. N. Appleton, B. A. Joshi +5

We present Chandra and XMM-Newton X-ray observations of the compact group HCG 57, and optical integral field spectroscopy of the interacting galaxy pair HCG 57A/D. These two spiral…