English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present results from our ALMA Cycle 0 observations, at the frequenciesaround the HCN, HCO+, and HNC J=4-3 transition lines, of the luminous infraredgalaxy IRAS 20551-4250 at z=0.043, which is known to host an energeticallyimportant obscured AGN. In addition to the targeted HCN, HCO+, and HNC J=4-3emission lines, two additional strong emission lines are seen, which weattribute to H2S and CH3CN(+CCH). The HCN-to-HCO+ J=4-3 flux ratio (~0.7) ishigher than in the other starburst-dominated galaxy (~0.2) observed in our ALMACycle 0 program. We tentatively (~5 sigma) detected the vibrationally excited(v2=1) HCN J=4-3 (l=1f) emission line, which is important for testing aninfrared radiative pumping scenario for HCN. This is the second detection ofthis molecular transition in external galaxies. The most likely reason for thisdetection is not only the high flux of this emission line, but also the smallmolecular line widths observed in this galaxy, suggesting that vibrationalexcitation of HCN may be relatively common in AGN-hosting galaxies.

ALMA Detection of the Vibrationally Excited HCN J=4-3 Emission Line in the AGN-Hosting Luminous Infrared Galaxy IRAS 20551-4250