UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

LLAMA: normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies

Rosario, DJ; Burtscher, L; Davies, RI; Koss, M; Ricci, C; Lutz, D; Riffel, R; ... Veilleux, S; + view all (2018) LLAMA: normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies. Monthly Notices of the Royal Astronomical Society , 473 (4) pp. 5658-5679. 10.1093/mnras/stx2670. Green open access

[thumbnail of Saintonge_LLAMA. Normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies.pdf]
Preview
Text
Saintonge_LLAMA. Normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies.pdf - Published Version

Download (3MB) | Preview

Abstract

Using new Atacama Pathfinder Experiment and James Clerk Maxwell Telescope spectroscopy of the CO 2→1 line, we undertake a controlled study of cold molecular gas in moderately luminous (L_bol = 10⁴³⁻⁴⁴·⁵ erg s⁻¹) active galactic nuclei (AGN) and inactive galaxies from the Luminous Local AGN with Matched Analogs (LLAMA) survey. We use spatially resolved infrared photometry of the LLAMA galaxies from 2MASS, the Wide-field Infrared Survey Explorer the Infrared Astronomical Satellite and the Herschel Space Observatory (Herschel), corrected for nuclear emission using multicomponent spectral energy distribution fits, to examine the dust-reprocessed star formation rates, molecular gas fractions and star formation efficiencies (SFEs) over their central 1–3 kpc. We find that the gas fractions and central SFEs of both active and inactive galaxies are similar when controlling for host stellar mass and morphology (Hubble type). The equivalent central molecular gas depletion times are consistent with the discs of normal spiral galaxies in the local Universe. Despite energetic arguments that the AGN in LLAMA should be capable of disrupting the observable cold molecular gas in their central environments, our results indicate that nuclear radiation only couples weakly with this phase. We find a mild preference for obscured AGN to contain higher amounts of central molecular gas, which suggests connection between AGN obscuration and the gaseous environment of the nucleus. Systems with depressed SFEs are not found among the LLAMA AGN. We speculate that the processes that sustain the collapse of molecular gas into dense pre-stellar cores may also be a prerequisite for the inflow of material on to AGN accretion discs.

Type: Article
Title: LLAMA: normal star formation efficiencies of molecular gas in the centres of luminous Seyfert galaxies
Open access status: An open access version is available from UCL Discovery
DOI: 10.1093/mnras/stx2670
Publisher version: https://doi.org/10.1093/mnras/stx2670
Language: English
Additional information: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: methods: statistical, ISM: molecules, galaxies: ISM, galaxies: Seyfert, galaxies: star formation, infrared: galaxies
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy
URI: https://discovery.ucl.ac.uk/id/eprint/10040619
Downloads since deposit
77Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item