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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Context. Traditionally, supersonic turbulence is considered to be one of themost likely mechanisms to slow down the gravitational collapse in dense clumps,thereby enabling the formation of massive stars. However, several recentstudies have raised differing points of view based on observations carried outwith sufficiently high spatial and spectral resolution. These studies call fora re-evaluation of the role turbulence plays in massive star-forming regions.Aims. Our aim is to study the gas properties, especially the turbulence, in asample of massive star-forming regions with sufficient spatial and spectralresolution, which can both resolve the core fragmentation and the thermal linewidth. Methods. We observed NH3 metastable lines with the Very Large Array(VLA) to assess the intrinsic turbulence. Results. Analysis of the turbulencedistribution histogram for 32 identified NH3 cores reveals the presence ofthree distinct components. Furthermore, our results suggest that (1) sub- andtransonic turbulence is a prevalent (21 of 32) feature of massive star-formingregions and those cold regions are at early evolutionary stage. Thisinvestigation indicates that turbulence alone is insufficient to provide thenecessary internal pressure required for massive star formation, necessitatingfurther exploration of alternative candidates; and (2) studies of sevenmulti-core systems indicate that the cores within each system mainly sharesimilar gas properties and masses. However, two of the systems arecharacterized by the presence of exceptionally cold and dense cores that aresituated at the spatial center of each system. Our findings support thehub-filament model as an explanation for this observed distribution

The role of turbulence in high-mass star formation: Subsonic and transonic turbulence are ubiquitously found at early stages