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

Star clusters form via clustering star formation inside molecular clouds. Inorder to understand the dynamical evolution of star clusters in their earlyphase, in which star clusters are still embedded in their surrounding gas, weneed an accurate integration of individual stellar orbits without gravitationalsoftening in the systems including both gas and stars, as well as modelingindividual stars with a realistic mass function. We develop a new tree-directhybrid smoothed particle hydrodynamics/N-body code, ASURA+BRIDGE, in whichstars are integrated using a direct N-body scheme or PeTar, a particle-particleparticle-tree scheme code, without gravitational softening. In ASURA+BRIDGE,stars are assumed to have masses randomly drawn from a given initial massfunction. With this code, we perform star-cluster formation simulationsstarting from molecular clouds without gravitational softening. We find thatartificial dense cores in star-cluster centers due to the softening disappearwhen we do not use softening. We further demonstrate that star clusters arebuilt up via mergers of smaller clumps. Star clusters formed in our simulationsinclude some dynamically formed binaries with the minimum semi-major axes of afew au, and the binary fraction is higher for more massive stars.

SIRIUS project II: a new tree-direct hybrid code for smoothed particle hydrodynamics/N-body simulations of star clusters