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 report the latest set of spectropolarimetric observations of the magnetic$\beta$ Cep star $\xi^1$ CMa. The new observations confirm the long-periodmodel of Shultz et al.\ (2017), who proposed a rotational period of about 30years and predicted that in 2018 the star should pass through a magnetic null.In perfect agreement with this projection, all longitudinal magnetic field$\langle B_z \rangle$ measurements are close to 0 G. Remarkably, individualStokes $V$ profiles all display a crossover signature, which is consistent with$\langle B_z \rangle \sim 0$ but is {\em not} expected when $v\sin{i} \sim 0$.The crossover signatures furthermore exhibit pulsationally modulated amplitudeand sign variations. We show that these unexpected phenomena can all beexplained by a `radial crossover' effect related to the star's radialpulsations, together with an important deviation of the global field topologyfrom a purely dipolar structure, which we explore via a dipole+quadrupoleconfiguration as the simplest non-dipolar field.

The pulsationally modulated radial crossover signature of the slowly rotating magnetic B-type star $\xi^1$ CMa