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/

Zendy Plus

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

Zendy Tools

Zendy Open

The gamma-ray binary system PSR B1259-63/LS 2883 went through periastron inMay 2014. We report on the optical spectroscopic monitoring of the system from33 d before to 78 d after periastron, undertaken with the Southern AfricanLarge Telescope (SALT). The H{\alpha} and He I ({\lambda}6678) lines exhibit anorbital variation around periastron, with the line strengths reaching a maximum~13 d after periastron. The line strength is weaker than observed around theprevious periastron in 2010. There is also a marked change in the line-strengthand asymmetry around the first disc crossing. These observations are consistentwith the disruption of the circumstellar disc around periastron due to theinteraction with the pulsar.

Optical spectroscopy of PSR B1259-63/LS 2883 during the 2014 periastron passage with the Southern African Large Telescope