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

A fraction of the mid-$J$ ($J$= 14--13 to $J$= 24--23) CO emission detectedby the \textit{Herschel}/PACS observations of embedded young stellar objects(YSOs) has been attributed to the UV-heated outflow cavity walls. We haveapplied our newly developed self-consistent models of Photon-Dominated Region(PDR) and non-local thermal equilibrium line Radiative transfer In general Grid(RIG) to the \textit{Herschel} FIR observations of 27 low mass YSOs and oneintermediate mass YSO, NGC7129-FIRS2. When the contribution of the hotcomponent (traced by transitions of $J> 24$) is removed, the rotationaltemperature of the warm component is nearly constant with $\sim250$ K. This canbe reproduced by the outflow cavity wall ($n \geq 10^6\, \mathrm{cm}^{-3}$,$\log G_{0}/n \geq-4.5$, $\mathrm{log} G_0\ge 3$, $T_{\rm gas} \ge 300 $K, andX(CO)$ \ge 10^{-5}$) heated by a UV radiation field with a black bodytemperature of 15,000 K or 10,000 K. However, a shock model combined with aninternal PDR will be required to determine the quantitative contribution of aPDR relative to a shock to the mid-$J$ CO emission.

The warm CO gas along the UV-heated outflow cavity walls: a possible interpretation for the Herschel/PACS CO spectra of embedded YSOs