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

The Large Magellanic Cloud (LMC), the closest star forming galaxy with lowmetallicity, provides an ideal laboratory to study star formation in such anenvironment. The classical dense molecular gas thermometer NH3 is rarelyavailable in a low metallicity environment because of photoionization and alack of nitrogen atoms. Our goal is to directly measure the gas kinetictemperature with formaldehyde toward six star-forming regions in the LMC. Threerotational transitions of para-H2CO near 218 GHz were observed with the APEX12m telescope toward six star forming regions in the LMC. Those data arecomplemented by C18O 2-1 spectra. Using non-LTE modeling with RADEX, we derivethe gas kinetic temperature and spatial density, using as constraints themeasured para-H2CO 321-220/303-202 and para-H2CO 303-202/C18O 2-1 ratios.Excluding the quiescent cloud N159S, where only one para-H2CO line could bedetected, the gas kinetic temperatures derived from the preferred para-H2CO321-220/303-202 line ratios range from 35 to 63 K with an average of 47 K.Spatial densities of the gas derived from the paraH2CO 303-202/C18O 2-1 lineratios yield 0.4-2.9x10^5 cm^-3 with an average of 1.5x10^5 cm^-3. Temperaturesderived from the para-H2CO line ratio are similar to those obtained with thesame method from Galactic star forming regions and agree with results derivedfrom CO in the dense regions of the LMC. A comparison of kinetic temperaturesderived from para-H2CO with those from the dust also shows good agreement. Thissuggests that the dust and para-H2CO are well mixed in the studied star formingregions. A correlation between the gas kinetic temperatures derived frompara-H2CO and infrared luminosity, represented by the 250um flux, suggests thatthe kinetic temperatures traced by para-H2CO are correlated with the ongoingmassive star formation in the LMC.

Kinetic temperature of massive star forming molecular clumps measured with formaldehyde. II. The Large Magellanic Cloud