Testing a scaling relation between coherent radio emission and physical parameters of hot magnetic stars

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F22%3A00128184" target="_blank" >RIV/00216224:14310/22:00128184 - isvavai.cz</a>

Result on the web

<a href="https://academic.oup.com/mnras/article/517/4/5756/6780209" target="_blank" >https://academic.oup.com/mnras/article/517/4/5756/6780209</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/stac3123" target="_blank" >10.1093/mnras/stac3123</a>

Result language

angličtina

Original language name

Testing a scaling relation between coherent radio emission and physical parameters of hot magnetic stars

Original language description

Coherent radio emission via electron cyclotron maser emission (ECME) from hot magnetic stars was discovered more than two decades ago, but the physical conditions that make the generation of ECME favourable remain uncertain. Only recently was an empirical relation, connecting ECME luminosity with the stellar magnetic field and temperature, proposed to explain what makes a hot magnetic star capable of producing ECME. This relation was, however, obtained with just 14 stars. Therefore, it is important to examine whether this relation is robust. With the aim of testing the robustness, we conducted radio observations of five hot magnetic stars. This led to the discovery of three more stars producing ECME. We find that the proposed scaling relation remains valid after the addition of the newly discovered stars. However, we discovered that the magnetic field and effective temperature correlate for T-eff less than or similar to 16 kK (likely an artefact of the small sample size), rendering the proposed connection between ECME luminosity and T-eff unreliable. By examining the empirical relation in light of the scaling law for incoherent radio emission, we arrive at the conclusion that both types of emission are powered by the same magnetospheric phenomenon. Like the incoherent emission, coherent radio emission is indifferent to T-eff for late-B and A-type stars, but T-eff appears to become important for early-B type stars, possibly due to higher absorption, or higher plasma density at the emission sites suppressing the production of the emission.

Czech name

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Czech description

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Type

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

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

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

517

Issue of the periodical within the volume

4

Country of publishing house

GB - UNITED KINGDOM

Number of pages

14

Pages from-to

5756-5769

UT code for WoS article

000881809100032

EID of the result in the Scopus database

2-s2.0-85145351490