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

Cygnus OB2 provides a unique insight into the high-mass stellar content inone of the largest groups of young massive stars in our Galaxy. Althoughseveral studies of its massive population have been carried out over the lastdecades, an extensive spectroscopic study of the whole known O-star populationin the association is still lacking. In this work, we created the most completespectroscopic census of O stars carried out so far in Cygnus OB2 using alreadyexisting and new spectroscopy. We present the spectra for 78 O-type stars, fromwhich we identify new binary systems, obtain the distribution of rotationalvelocities, and determine the main stellar parameters for all the stars in theregion that have not been detected as double-line spectroscopic binaries. Wealso derive radii, luminosities, and masses for those stars with reliable Gaiaastrometry, in addition to creating the Hertzsprung-Russell Diagram tointerpret the evolutionary status of the association. This work has shown theimprovement reached when using accurate spectroscopic parameters and astrometryfor the interpretation of the evolutionary status of a population, revealing,in the case of Cygnus OB2, at least two star-forming bursts at $\sim$3 and$\sim$5 Myr. We find an apparent deficit of very fast rotators in thedistribution of rotational velocities. The inspection of the dynamicaldistribution of the sample has allowed us to identify nine O stars withpeculiar proper motions and discuss a possible dynamical ejection scenario orpast supernova explosions in the region.

Spectroscopic characterization of the known O-star population in Cygnus OB2. Evidence of multiple star-forming bursts