6 papers · 1 filter
Classifying Quasar Types Without a Spectrum
Adrien Hélias, Pauline Barmby, Sarah C. Gallagher +2
Distinguishing between Type 1 and Type 2 quasars is important because it helps us understand accretion regimes, black hole mass scaling, disk instabilities and feedback processes i…
Investigating the AGN variability timescale -- black hole mass relationship with Gaia, SDSS and ZTF
Adrien Hélias, Sarah C. Gallagher, Pauline Barmby
Active galactic nuclei (AGNs) exhibit variability in their luminosities with timescales that correlate with the mass of the black hole at the centre of the AGN. Presently, the empi…
AGN--Host Galaxy Image Decomposition with JWST
Callum Dewsnap, Pauline Barmby, Sarah C. Gallagher
The ability to disentangle the light of an AGN from its host galaxy is strongly dependent on the spatial resolution and depth of the imaging. As the capabilities of imaging systems…
TONGS: A Treasury Of Nearby Galaxy Surveys
Hannah S. Christie, Adrien Hélias, Matheus do Carmo Carvalho +1
The beginning of the 21st century marked the "modern era of galaxy surveys" in astronomy. Rapid innovation in observing technology, combined with the base built by galaxy catalogs…
Comparing Gaia, NED and SIMBAD source classifications in nearby galaxies
J. Hales, P. Barmby
Gaia Data Release 3 (DR3) provides the first classifications for the sources in Gaia's all-sky database. Most Gaia sources are stars in the Milky Way, but DR3 also contains many so…
Deconstructing a galaxy: colour distributions of point sources in Messier 83
A. Kiar, P. Barmby, A. Hidalgo
What do we see when we look at a nearby, well-resolved galaxy? Thousands of individual sources are detected in multiband imaging observations of even a fraction of a nearby galaxy,…