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 Herschel PACS and SPIRE spectroscopy of the most importantfar-infrared cooling lines in M51, [CII](158 \mu m), [NII](122 & 205 \mu m),[OI](63 and 145 \mu m) and [OIII](88 \mu m). We compare the observed flux ofthese lines with the predicted flux from a photon dominated region model todetermine characteristics of the cold gas such as density, temperature and thefar-ultraviolet radiation field, G_0, resolving details on physical scales ofroughly 600 pc. We find an average [CII]/F_TIR of 4 x 10^{-3}, in agreementwith previous studies of other galaxies. A pixel-by-pixel analysis of fourdistinct regions of M51 shows a radially decreasing trend in both thefar-ultraviolet (FUV) radiation field, G_0 and the hydrogen density, n, peakingin the nucleus of the galaxy, then falling off out to the arm and interarmregions. We see for the first time that the FUV flux and gas density aresimilar in the differing environments of the arm and interarm regions,suggesting that the inherent physical properties of the molecular clouds inboth regions are essentially the same.

Regional variations in the dense gas heating and cooling in M51 from Herschel far-infrared spectroscopy