J 2019

Epicyclic Oscillations in the Hartle-Thorne External Geometry

URBANCOVÁ, Gabriela, Martin URBANEC, Gabriel TÖRÖK, Zdeněk STUCHLÍK, Martin BLASCHKE et. al.

Základní údaje

Originální název

Epicyclic Oscillations in the Hartle-Thorne External Geometry

Autoři

URBANCOVÁ, Gabriela (203 Česká republika, domácí), Martin URBANEC (203 Česká republika, garant, domácí), Gabriel TÖRÖK (203 Česká republika, domácí), Zdeněk STUCHLÍK (203 Česká republika, domácí), Martin BLASCHKE (203 Česká republika, domácí) a John MILLER (826 Velká Británie a Severní Irsko)

Vydání

Astrophysical Journal, 2019, 0004-637X

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Odkazy

URL

Kód RIV

RIV/47813059:19240/19:A0000427

Organizační jednotka

Filozoficko-přírodovědecká fakulta v Opavě

DOI

http://dx.doi.org/10.3847/1538-4357/ab1b4c

UT WoS

000469433800002

Klíčová slova anglicky

stars: oscillations; stars: neutron; stars: rotation; X-rays: binaries

Štítky

, GA17-16287S, GB14-37086G, LTC18058, RIVOK, SGS12-2019, SGS13-2019, SGS14-2016, SGS15-2016

Příznaky

Mezinárodní význam, Recenzováno

Návaznosti

GA17-16287S, projekt VaV. GB14-37086G, projekt VaV. LTC18058, projekt VaV.
Změněno: 21. 4. 2020 10:31, Ing. Petra Skoumalová

Anotace

V originále

The external Hartle-Thorne geometry, which describes the spacetime outside a slowly rotating compact star, is characterized by the gravitational mass M, angular momentum J, and quadrupole moment Q of the star and gives a convenient description, which, for the rotation frequencies of more than 95% of known pulsars, is sufficiently accurate for most purposes. We focus here on the motion of particles in these spacetimes, presenting a detailed systematic analysis of the frequency properties of radial and vertical epicyclic motion and of orbital motion. Our investigation is motivated by X-ray observations of binary systems containing a rotating neutron star that is accreting matter from its binary companion. In these systems, twin high-frequency quasi-periodic oscillations (QPOs) are sometimes observed with a frequency ratio approaching 3:2 or 5:4, and these may be explained by models involving the orbital and epicyclic frequencies of quasi-circular geodesic motion. In our analysis, we use realistic equations of state for the stellar matter and proceed in a self-consistent way, following the Hartle-Thorne approach in calculating both the corresponding values of Q, M, and J for the stellar model and the properties of the surrounding spacetime. Our results are then applied to a range of geodetical models for QPOs. A key feature of our study is that it implements the recently discovered universal relations among neutron-star parameters so that the results can be directly used for models with different masses M, radii R, and rotational frequencies f_(rot).
Zobrazeno: 27. 11. 2024 02:05