A study of the Czernik 2 and NGC 7654 open clusters using CCD UBV photometric and Gaia EDR3 data

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F21%3A00122382" target="_blank" >RIV/00216224:14310/21:00122382 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1007/s10509-021-03975-x" target="_blank" >https://doi.org/10.1007/s10509-021-03975-x</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s10509-021-03975-x" target="_blank" >10.1007/s10509-021-03975-x</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A study of the Czernik 2 and NGC 7654 open clusters using CCD UBV photometric and Gaia EDR3 data

Popis výsledku v původním jazyce

We analysed the open clusters Czernik 2 and NGC 7654 using CCD UBV photometric and Gaia Early Data Release 3 (EDR3) photometric and astrometric data. Structural parameters of the two clusters were derived, including the physical sizes of Czernik 2 being r=5′ and NGC 7654 as 8′. We calculated membership probabilities of stars based on their proper motion components as released in the Gaia EDR3. To identify member stars of the clusters, we used these membership probabilities taking into account location and the impact of binarity on main-sequence stars. We used membership probabilities higher than P=0.5 to identify 28 member stars for Czernik 2 and 369 for NGC 7654. The mean proper motion components (μαcosδ, μδ) of Czernik 2 were derived as (−4.03±0.04, −0.99±0.05) mas yr−1 and for NGC 7654 as (−1.89±0.03, −1.20±0.03) mas yr−1. We estimated colour-excesses and metallicities separately using (U−B)×(B−V) two-colour diagrams to derive homogeneously determined parameters. The derived E(B−V) colour excess is 0.46±0.02 mag for Czernik 2 and 0.57±0.04 mag for NGC 7654. [Fe/H] metallicities were obtained for the first time for both clusters, −0.08±0.02 dex for Czernik 2 and −0.05±0.01 dex for NGC 7654. Keeping the reddening and metallicity as constant quantities, we fitted PARSEC models using V×(B−V) and V×(U−B) colour-magnitude diagrams, resulting in estimated distance moduli and ages of the two clusters. We obtained the distance modulus for Czernik 2 as 12.80±0.07 mag and for NGC 7654 as 13.20±0.16 mag, which coincide with ages of 1.2±0.2 Gyr and 120±20 Myr, respectively. The distances to the clusters were calculated using the Gaia EDR3 trigonometric parallaxes and compared with the literature. We found good agreement between the distances obtained in this study and the literature. Present day mass function slopes for both clusters are comparable with the value of Salpeter (1955), being X=−1.37±0.24 for Czernik 2 and X=−1.39±0.19 for NGC 7654.

Název v anglickém jazyce

A study of the Czernik 2 and NGC 7654 open clusters using CCD UBV photometric and Gaia EDR3 data

Popis výsledku anglicky

We analysed the open clusters Czernik 2 and NGC 7654 using CCD UBV photometric and Gaia Early Data Release 3 (EDR3) photometric and astrometric data. Structural parameters of the two clusters were derived, including the physical sizes of Czernik 2 being r=5′ and NGC 7654 as 8′. We calculated membership probabilities of stars based on their proper motion components as released in the Gaia EDR3. To identify member stars of the clusters, we used these membership probabilities taking into account location and the impact of binarity on main-sequence stars. We used membership probabilities higher than P=0.5 to identify 28 member stars for Czernik 2 and 369 for NGC 7654. The mean proper motion components (μαcosδ, μδ) of Czernik 2 were derived as (−4.03±0.04, −0.99±0.05) mas yr−1 and for NGC 7654 as (−1.89±0.03, −1.20±0.03) mas yr−1. We estimated colour-excesses and metallicities separately using (U−B)×(B−V) two-colour diagrams to derive homogeneously determined parameters. The derived E(B−V) colour excess is 0.46±0.02 mag for Czernik 2 and 0.57±0.04 mag for NGC 7654. [Fe/H] metallicities were obtained for the first time for both clusters, −0.08±0.02 dex for Czernik 2 and −0.05±0.01 dex for NGC 7654. Keeping the reddening and metallicity as constant quantities, we fitted PARSEC models using V×(B−V) and V×(U−B) colour-magnitude diagrams, resulting in estimated distance moduli and ages of the two clusters. We obtained the distance modulus for Czernik 2 as 12.80±0.07 mag and for NGC 7654 as 13.20±0.16 mag, which coincide with ages of 1.2±0.2 Gyr and 120±20 Myr, respectively. The distances to the clusters were calculated using the Gaia EDR3 trigonometric parallaxes and compared with the literature. We found good agreement between the distances obtained in this study and the literature. Present day mass function slopes for both clusters are comparable with the value of Salpeter (1955), being X=−1.37±0.24 for Czernik 2 and X=−1.39±0.19 for NGC 7654.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Astrophysics and Space Science

ISSN

0004-640X

e-ISSN

1572-946X

Svazek periodika

366

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

19

Strana od-do

68

Kód UT WoS článku

000692376300001

EID výsledku v databázi Scopus

2-s2.0-85111306945