On the Oosterhoff dichotomy in the Galactic bulge - II. Kinematical distribution

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F19%3A00111910" target="_blank" >RIV/00216224:14310/19:00111910 - isvavai.cz</a>

Výsledek na webu

<a href="https://academic.oup.com/mnras/article/487/3/3270/5509593" target="_blank" >https://academic.oup.com/mnras/article/487/3/3270/5509593</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/stz1484" target="_blank" >10.1093/mnras/stz1484</a>

Jazyk výsledku

angličtina

Název v původním jazyce

On the Oosterhoff dichotomy in the Galactic bulge - II. Kinematical distribution

Popis výsledku v původním jazyce

We present a kinematical study of RR Lyrae stars associated with two Oosterhoff groups in the Galactic bulge, We used data published in the first paper of the series, plus proper motions from the Gaia Data Release 2, and radial velocities from the literature, A 6D kinematical and spatial solution was obtained for 429 RR Lyrae stars, We use a model of the Galactic gravitational potential to infer stellar orbits. We did not find a difference between the Oosterhoff groups in the individual components of the space velocity. We report that foreground and background stars with respect to the Galactic bulge stand out in the mean V velocity component, which we interpret as a sign of the Galactic rotation. The movement of the studied stars in the central region of the Galactic bulge is consistent with random motions expected for a classical bulge component. From the orbital integration, we estimate that 8 per cent of the RR Lyrae stars are halo interlopers currently located in the Galactic bulge. The majority of the stars' orbits are within a 3 kpc radius from the Galactic bulge. The fraction of Oosterhoff II stars increases with increasing Galactic latitude, as well as towards longer orbital periods. We found several RR Lyrae stars with high space velocities, one of which has an extremely long orbital period of similar to 1 Gyr. We conclude that based on their kinematics, the vast majority of the stars in our sample do not seem to contribute to the boxy/peanut component of the Galactic bulge.

Název v anglickém jazyce

On the Oosterhoff dichotomy in the Galactic bulge - II. Kinematical distribution

Popis výsledku anglicky

We present a kinematical study of RR Lyrae stars associated with two Oosterhoff groups in the Galactic bulge, We used data published in the first paper of the series, plus proper motions from the Gaia Data Release 2, and radial velocities from the literature, A 6D kinematical and spatial solution was obtained for 429 RR Lyrae stars, We use a model of the Galactic gravitational potential to infer stellar orbits. We did not find a difference between the Oosterhoff groups in the individual components of the space velocity. We report that foreground and background stars with respect to the Galactic bulge stand out in the mean V velocity component, which we interpret as a sign of the Galactic rotation. The movement of the studied stars in the central region of the Galactic bulge is consistent with random motions expected for a classical bulge component. From the orbital integration, we estimate that 8 per cent of the RR Lyrae stars are halo interlopers currently located in the Galactic bulge. The majority of the stars' orbits are within a 3 kpc radius from the Galactic bulge. The fraction of Oosterhoff II stars increases with increasing Galactic latitude, as well as towards longer orbital periods. We found several RR Lyrae stars with high space velocities, one of which has an extremely long orbital period of similar to 1 Gyr. We conclude that based on their kinematics, the vast majority of the stars in our sample do not seem to contribute to the boxy/peanut component of the Galactic bulge.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/EF16_027%2F0008360" target="_blank" >EF16_027/0008360: Postdoc@MUNI</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

1365-2966

Svazek periodika

487

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

9

Strana od-do

3270-3278

Kód UT WoS článku

000478053200024

EID výsledku v databázi Scopus

2-s2.0-85072277662