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

We study self-gravitating, hydrostatic spheres with a polytropic equation of state P ∝ ρ (where γ is the specific heat ratio of the gas), considering structures with γ ≈ 1 as a model for molecular cloud cores with small departures from isothermality. We derive the properties (i.e., mass, radius and center to edge density ratio) as a function of γ for the maximal stable sphere through an application of “Bonnor’s stability criterion”. We find that in the γ = 1→ 4/3 range the mass of the maximal sphere (for a given central temperature) is almost constant, and that its radius and center to edge density ratio are growing functions of γ. We therefore have maximal stable, self-gravitating spheres with similar masses, but with increasing center to edge density contrasts for increasing departures from isothermality.

THE PROPERTIES AND STABILITY OF SELF-GRAVITATING, POLYTROPIC SPHERES WITH γ = 1 TO 1.4 SPECIFIC HEAT RATIOS