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

We have carried out K-band speckle observations of a sample of 114 X-rayselected weak-line T Tauri stars in the nearby Scorpius-Centaurus OBassociation. We find that for binary T Tauri stars closely associated to theearly type stars in Upper Scorpius, the youngest subgroup of the OBassociation, the peak in the distribution of binary separations is at 90 A.U.For binary T Tauri stars located in the direction of an older subgroup, but notclosely associated to early type stars, the peak in the distribution is at 215A.U. A Kolmogorov-Smirnov test indicates that the two binary populations do notresult from the same distibution at a significance level of 98%. Apparently,the same physical conditions which facilitate the formation of massive starsalso facilitate the formation of closer binaries among low-mass stars, whereasphysical conditions unfavorable for the formation of massive stars lead to theformation of wider binaries among low-mass stars. The outcome of the binaryformation process might be related to the internal turbulence and the angularmomentum of molecular cloud cores, magnetic field, the initial temperaturewithin a cloud, or - most likely - a combination of all of these. We concludethat the distribution of binary separations is not a universal quantity, andthat the broad distribution of binary separations observed among main-sequencestars can be explained by a superposition of more peaked binary distributionsresulting from various star forming environments. The overall binary frequencyamong pre-main-sequence stars in individual star forming regions is notnecessarily higher than among main-sequence stars.

Star Formation Environments and the Distribution of Binary Separations