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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Approximately 10% of massive OBA main-sequence (MS) and pre-MS stars harbourstrong, large-scale magnetic fields. At the same time there is a dearth ofmagnetic stars in close binaries. A process generating strong magnetic fieldsonly in some stars must be responsible with the merging of pre-MS and MS starsbeing suggested as one such channel. Stars emerging from the coalescence of twoMS stars are rejuvenated, appearing younger than they are. They can thereforebe identified by comparison with reference clocks. Here we predict therejuvenation of MS merger products over a wide range of masses and binaryconfigurations calibrated to smoothed-particle-hydrodynamical merger models. Wefind that the rejuvenation is of the order of the nuclear timescale and isstrongest in the lowest-mass mergers and the most evolved binary progenitorswith the largest mass ratios. These predictions allow us to put constraints onthe binary progenitors of merger products. We show that the magnetic stars HR2949 and $\tau$ Sco are younger than the potential binary companion HR 2948 andthe Upper-Sco association, respectively, making them promising mergercandidates. We find that the age discrepancies and the potential binaryprogenitors of both are consistent with them being rejuvenated merger products,implying that their magnetic fields may originate from this channel. Searchingfor age discrepancies in magnetic stars is therefore a powerful way to explorewhich fraction of magnetic stars may have obtained their strong magnetic fieldin MS mergers and to improve our understanding of magnetism in massive starsand their remnants.

Rejuvenation of stellar mergers and the origin of magnetic fields in massive stars