J 2021

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

AKBULUT, B., S. AK, T. YONTAN, S. BILIR, T. AK et. al.

Základní údaje

Originální název

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

Autoři

AKBULUT, B. (garant), S. AK, T. YONTAN, S. BILIR, T. AK, T. BANKS, E. KAAN ULGEN a Ernst PAUNZEN (40 Rakousko, domácí)

Vydání

Astrophysics and Space Science, Springer, 2021, 0004-640X

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Nizozemské království

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 1.909

Kód RIV

RIV/00216224:14310/21:00122382

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000692376300001

Klíčová slova anglicky

Galaxy: open cluster and associations: individual: Czernik 2 and NGC 7654; Stars: Hertzsprung Russell (HR) diagram

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 20. 9. 2021 14:18, Mgr. Marie Šípková, DiS.

Anotace

V originále

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.