Discovery of extraordinary X-ray emission from magnetospheric interaction in the unique binary stellar system ϵ Lupi

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00131624" target="_blank" >RIV/00216224:14310/23:00131624 - isvavai.cz</a>

Result on the web

<a href="https://arxiv.org/abs/2304.12882" target="_blank" >https://arxiv.org/abs/2304.12882</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/stad1276" target="_blank" >10.1093/mnras/stad1276</a>

Result language

angličtina

Original language name

Discovery of extraordinary X-ray emission from magnetospheric interaction in the unique binary stellar system ϵ Lupi

Original language description

We report detailed X-ray observations of the unique binary system ϵ Lupi, the only known short-period binary consisting of two magnetic early-type stars. The components have comparably strong, but anti-aligned magnetic fields. The orbital and magnetic properties of the system imply that the magnetospheres overlap at all orbital phases, suggesting the possibility of variable inter-star magnetospheric interaction due to the non-negligible eccentricity of the orbit. To investigate this effect, we observed the X-ray emission from ϵ Lupi, both near and away from periastron passage, using the Neutron Star Interior Composition Explorer mission (NICER) X-ray Telescope. We find that the system produces excess X-ray emission at the periastron phase, suggesting the presence of variable inter-star magnetospheric interaction. We also discover that the enhancement at periastron is confined to a very narrow orbital phase range (⁠≈5 per cent of the orbital period), but the X-ray properties close to periastron phase are similar to those observed away from periastron. From these observations, we infer that the underlying cause is magnetic reconnection heating the stellar wind plasma, rather than shocks produced by wind–wind collision. Finally, by comparing the behavior of ϵ Lupi with that observed for cooler magnetic binary systems, we propose that elevated X-ray flux at periastron phase is likely a general characteristic of interacting magnetospheres irrespective of the spectral types of the constituent stars.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

1365-2966

Volume of the periodical

522

Issue of the periodical within the volume

4

Country of publishing house

GB - UNITED KINGDOM

Number of pages

23

Pages from-to

5805-5827

UT code for WoS article

000994685100007

EID of the result in the Scopus database

2-s2.0-85161535047