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

[Abridged] The interstellar medium is observed to be organised in filamentarystructures, as well as neutral (HI) and ionized (HII) bubbles. The expandingnature of these bubbles makes them shape their surroundings and possibly play arole in the formation and evolution of interstellar filaments. We present APEX$^{13}$CO and C$^{18}$O(2-1) observations of the NGC 6334 molecular cloud. Weinvestigate the gas velocity structure along and across the 50 pc-long cloudand towards 75 identified velocity-coherent-filaments (VCFs). We measure awealth of velocity gradients along the VCFs. We derive the column density andvelocity power spectra of the VCFs. These power spectra are well representedwith power laws showing similar slopes for both quantities (with a mean ofabout -2), albeit some differ by up to a factor of two. The position velocitydiagrams perpendicular to three VCFs show the V-shaped velocity pattern,corresponding to a bent structure in velocity space with the filament at thetip of the V surrounded by an extended structure connected to it with avelocity gradient. This velocity structure is qualitatively similar to thatresulting from numerical simulations of filament formation from large-scalecompression from propagating shock fronts. In addition, the radial profilesperpendicular to these VCFs hint to small-scale internal impacts fromneighbouring HII bubbles. The observed opposite curvature in velocity spacetowards the VCFs points to various origins of large-scale external compressionsfrom propagating HI bubbles. This suggests the plausible importance of multipleHI compressions, separated in space and time, in the formation and evolution ofmolecular clouds and their star formation history. These latter atomiccompressions due to past and distant star formation events are complemented bythe impact of HII bubbles from present time and local star formation activity.

Velocity structure of the 50 pc-long NGC 6334 filamentary cloud: Hints of multiple compressions and their impact on the cloud properties?