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

Pillars and globules are present in many high-mass star-forming regions, suchas the Eagle nebula (M16) and the Rosette molecular cloud, and understandingtheir origin will help characterize triggered star formation. The formationmechanisms of these structures are still being debated. Recent numericalsimulations have shown how pillars can arise from the collapse of the shell inon itself and how globules can be formed from the interplay of the turbulentmolecular cloud and the ionization from massive stars. The goal here is to testthis scenario through recent observations of two massive star-forming regions,M16 and Rosette. The column density structure of the interface betweenmolecular clouds and H ii regions was characterized using column density mapsobtained from far-infrared imaging of the Herschel HOBYS key programme. Then,the DisPerSe algorithm was used on these maps to detect the compressed layersaround the ionized gas and pillars in different evolutionary states. Finally,their velocity structure was investigated using CO data, and all observationalsignatures were tested against some distinct diagnostics established fromsimulations. The column density profiles have revealed the importance ofcompression at the edge of the ionized gas. The velocity properties of thestructures, i.e. pillars and globules, are very close to what we predict fromthe numerical simulations. We have identified a good candidate of a nascentpillar in the Rosette molecular cloud that presents the velocity pattern of theshell collapsing on itself, induced by a high local curvature. Globules have abulk velocity dispersion that indicates the importance of the initialturbulence in their formation, as proposed from numerical simulations.Altogether, this study re-enforces the picture of pillar formation by shellcollapse and globule formation by the ionization of highly turbulent clouds.

Pillars and globules at the edges of H ii regions, Confronting Herschel observations and numerical simulations