4 papers
X-ray and optical decline of the intermediate mass black hole HLX-1
Roberto Soria, Maya Garbaccio Gili, Francesco Massaro +2
HLX-1 is a prominent intermediate-mass black hole (IMBH) candidate, historically exhibiting recurrent X-ray outbursts with spectral state transitions analogous to those observed in…
Supermassive black hole mass measurement in the spiral galaxy NGC 4736 Using JWST/NIRSpec stellar kinematics
Dieu D. Nguyen, Hai N. Ngo, Tinh Q. T. Le +12
We present accurate mass measurements of the central supermassive black hole (SMBH) in NGC 4736 (M 94).\ We used the ``gold-standard" stellar absorption features (CO band heads) at…
Dot to dot: high- little red dots in - diagrams with galaxy-morphology-specific scaling relations
Alister W. Graham, Igor V. Chilingarian, Dieu D. Nguyen +3
The high redshift 'little red dots' (LRDs) detected with the James Webb Space Telescope are considered to be the cores of emerging galaxies that host active galactic nuclei (AGN).…
Recipes for ULX formation: necessary ingredients and garnishments
Roberto Soria
I summarize the main observational features that seem to recur more frequently in the ULX population. I speculate that two of the most important physical requirements for ULX forma…