Constarium
← Search

Table · dataset · 2026

Properties and asymmetries of QSOs host galaxies

Listed in IVOA Registry (Virtual Observatory)

How does the host galaxy morphology influence a central quasar or vice versa?

Description

We address this question by measuring the asymmetries of 2424 SDSS quasar hosts at 0.2 < z < 0.8 using broad-band (grizy) images from the Hyper Suprime-Cam Subaru Strategic Program. Control galaxies (without quasars) are selected by matching the redshifts and stellar masses of the quasar hosts.

A two-step pipeline is run to decompose the PSF and Sersic components and then measure asymmetry indices (ACAS, Aouter, and Ashape) of each quasar host and control galaxy. We find a mild correlation between host asymmetry and AGN bolometric luminosity (Lbol) for the full sample (spearman correlation of 0.37) while a stronger trend is evident at the highest luminosities (L_bol_>45). This then manifests itself into quasar hosts being more asymmetric, on average, when they harbour a more massive and highly accreting black hole.

Read the rest (2 more)

The merger fraction also positively correlates with Lbol and reaches up to 35 per cent for the most luminous. Compared to control galaxies, quasar hosts are marginally more asymmetric (excess of 0.017 in median at 9.4{sigma} level) and the merger fractions are similar (~16.5 per cent). We quantify the dependence of asymmetry on optical band that demonstrates that mergers are more likely to be identified with the bluer bands and the correlation between Lbol and asymmetry is also stronger in such bands.

We stress that the band dependence, indicative of a changing stellar population, is an important factor in considering the influence of mergers on AGN activity.

Links

Topics

Stated by source
Infrared · Optical
Inferred from text
Image 65%
Provenance · 1 source records, 10 field assertions
SourceKeyLast seenRaw
IVOA Registry (Virtual Observatory)ivo://cds.vizier/j/mnras/521/527213 d agoJSON v1
FieldAssertionExtractorEvidence
access_levelsource · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[field].local:field:astronomymapping · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].ivoa_waveband:infraredsource · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].ivoa_waveband:opticalsource · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].local:modality:imageenrichment · IVOA Registrykeyword-concept-rules@1.0.0title+description (65%)
descriptionsource · IVOA Registryconnector:ivoa_registry@1.0.0rr.resource.res_description
license_textsource · IVOA Registryconnector:ivoa_registry@1.0.0
publication_datesource · IVOA Registryconnector:ivoa_registry@1.0.0
titlesource · IVOA Registryconnector:ivoa_registry@1.0.0rr.resource.res_title
updated_datesource · IVOA Registryconnector:ivoa_registry@1.0.0