2018
Differential rotation in magnetic chemically peculiar stars
MIKULÁŠEK, Zdeněk, Jiří KRTIČKA, Ernst PAUNZEN, Michal ŠVANDA, Stephan HÜMMERICH et. al.Základní údaje
Originální název
Differential rotation in magnetic chemically peculiar stars
Autoři
MIKULÁŠEK, Zdeněk (203 Česká republika, garant, domácí), Jiří KRTIČKA (203 Česká republika, domácí), Ernst PAUNZEN (40 Rakousko, domácí), Michal ŠVANDA (203 Česká republika), Stephan HÜMMERICH (276 Německo), Klaus BERNHARD (276 Německo), Miroslav JAGELKA (703 Slovensko, domácí), Jan JANÍK (203 Česká republika, domácí), Greg W. HENRY (840 Spojené státy) a Matthew E. SHULTZ
Vydání
Contributions of the Astronomical Observatory Skalnaté Pleso, 2018, 1335-1842
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10308 Astronomy
Stát vydavatele
Slovensko
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 0.833
Kód RIV
RIV/00216224:14310/18:00101279
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000432791300028
Klíčová slova anglicky
stars: chemically peculiar; stars: rotation; stars: individual: sigma Ori E; CU Vir; V901 Ori; and BS Cir; space vehicles: Kepler
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 23. 4. 2024 12:36, Mgr. Michal Petr
V originále
Magnetic chemically peculiar (mCP) stars constitute about 10% of upper-main-sequence stars and are characterized by strong magnetic fields and abnormal photospheric abundances of some chemical elements. Most of them exhibit strictly periodic light, magnetic, radio, and spectral variations that can be fully explained by a rigidly rotating main-sequence star with persistent surface structures and a stable global magnetic field. Long-term observations of the phase curves of these variations enable us to investigate possible surface differential rotation with unprecedented accuracy and reliability. The analysis of the phase curves in the best-observed mCP stars indicates that the location and the contrast of photometric and spectroscopic spots as well as the geometry of the magnetic field remain constant for at least many decades. The strict periodicity of mCP variables supports the concept that the outer layers of upper-main-sequence stars do not rotate differentially. However, there is a small, inhomogeneous group consisting of a few mCP stars whose rotation periods vary on timescales of decades. The period oscillations may reflect real changes in the angular velocity of outer layers of the stars which are anchored by their global magnetic fields. In CU Vir, V901 Ori, and perhaps BS Cir, the rotational period variation indicates the presence of vertical differential rotation; however, its exact nature has remained elusive until now. The incidence of mCP stars with variable rotational periods is currently investigated using a sample of fifty newly identified Kepler mCP stars.
Česky
Magnetic chemically peculiar (mCP) stars constitute about 10% of upper-main-sequence stars and are characterized by strong magnetic fields and abnormal photospheric abundances of some chemical elements. Most of them exhibit strictly periodic light, magnetic, radio, and spectral variations that can be fully explained by a rigidly rotating main-sequence star with persistent surface structures and a stable global magnetic field. Long-term observations of the phase curves of these variations enable us to investigate possible surface differential rotation with unprecedented accuracy and reliability. The analysis of the phase curves in the best-observed mCP stars indicates that the location and the contrast of photometric and spectroscopic spots as well as the geometry of the magnetic field remain constant for at least many decades. The strict periodicity of mCP variables supports the concept that the outer layers of upper-main-sequence stars do not rotate differentially. However, there is a small, inhomogeneous group consisting of a few mCP stars whose rotation periods vary on timescales of decades. The period oscillations may reflect real changes in the angular velocity of outer layers of the stars which are anchored by their global magnetic fields. In CU Vir, V901 Ori, and perhaps BS Cir, the rotational period variation indicates the presence of vertical differential rotation; however, its exact nature has remained elusive until now. The incidence of mCP stars with variable rotational periods is currently investigated using a sample of fifty newly identified Kepler mCP stars.
Návaznosti
| GA16-01116S, projekt VaV |
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