KRTIČKA, Jiří, Zdeněk MIKULÁŠEK, Petr KURFÜRST a Mary E. OKSALA. Photometric signatures of corotating magnetospheres of hot stars governed by higher-order magnetic multipoles. Astronomy & Astrophysics. EDP Sciences, 2022, roč. 659, March, s. 1-14. ISSN 0004-6361. Dostupné z: https://dx.doi.org/10.1051/0004-6361/202141997.
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Základní údaje
Originální název Photometric signatures of corotating magnetospheres of hot stars governed by higher-order magnetic multipoles
Autoři KRTIČKA, Jiří (203 Česká republika, garant, domácí), Zdeněk MIKULÁŠEK (203 Česká republika, domácí), Petr KURFÜRST (203 Česká republika, domácí) a Mary E. OKSALA (840 Spojené státy).
Vydání Astronomy & Astrophysics, EDP Sciences, 2022, 0004-6361.
Další údaje
Originální jazyk angličtina
Typ výsledku Článek v odborném periodiku
Obor 10308 Astronomy
Stát vydavatele Francie
Utajení není předmětem státního či obchodního tajemství
WWW URL
Impakt faktor Impact factor: 6.500
Kód RIV RIV/00216224:14310/22:00125321
Organizační jednotka Přírodovědecká fakulta
Doi http://dx.doi.org/10.1051/0004-6361/202141997
UT WoS 000762473500007
Klíčová slova anglicky stars: magnetic field; stars: chemically peculiar; stars: early-type; circumstellar matter; stars: variables: general
Štítky rivok
Příznaky Mezinárodní význam, Recenzováno
Změnil Změnila: Mgr. Marie Šípková, DiS., učo 437722. Změněno: 25. 3. 2022 11:11.
Anotace
The light curves of magnetic, chemically peculiar stars typically show periodic variability due to surface spots that in most cases can be modeled by low-order harmonic expansion. However, high-precision satellite photometry reveals tiny complex features in the light curves of some of these stars that are difficult to explain as caused by a surface phenomenon under reasonable assumptions. These features might originate from light extinction in corotating magnetospheric clouds supported by a complex magnetic field dominated by higher-order multipoles. We aim to understand the photometric signatures of corotating magnetospheres that are governed by higher-order multipoles. We determined the location of magnetospheric clouds from the minima of the effective potential along the magnetic field lines for different orders of multipoles and their combination. From the derived magnetospheric density distribution, we calculated light curves accounting for absorption and subsequent emission of light. For axisymmetric multipoles, the rigidly rotating magnetosphere model is able to explain the observed tiny features in the light curves only when the higher-order multipoles dominate the magnetic field not only at the stellar surface, but even at the Kepler radius. However, even a relatively weak nonaxisymmetric component leads to warping of equilibrium surfaces. This introduces structures that can explain the tiny features observed in the light curves of chemically peculiar stars. The light emission contributes to the light variability only if a significant fraction of light is absorbed in the magnetosphere.
VytisknoutZobrazeno: 14. 5. 2024 07:38