J 2021

New mercury-manganese stars and candidates from LAMOST DR4

PAUNZEN, Ernst; S. HUMMERICH a K. BERNHARD

Základní údaje

Originální název

New mercury-manganese stars and candidates from LAMOST DR4

Autoři

PAUNZEN, Ernst (40 Rakousko, garant, domácí); S. HUMMERICH a K. BERNHARD

Vydání

Astronomy and Astrophysics, Les Ulis, EDP Sciences, 2021, 0004-6361

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Francie

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 6.240

Kód RIV

RIV/00216224:14310/21:00121093

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000606855300001

EID Scopus

2-s2.0-85099068626

Klíčová slova anglicky

stars: chemically peculiar; stars: abundances; stars: variables: general

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 16. 5. 2022 11:02, Mgr. Marie Novosadová Šípková, DiS.

Anotace

V originále

Aims. The present work presents our efforts at identifying new mercury-manganese (HgMn/CP3) stars using spectra obtained with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST).Methods. Suitable candidates were searched for among pre-selected early-type spectra from LAMOST DR4 using a modified version of the MKCLASS code that probes several HgII and MnII features. The spectra of the resulting 332 candidates were visually inspected. Using parallax data and photometry from Gaia DR2, we investigated magnitudes, distances from the Sun, and the evolutionary status of our sample stars. We also searched for variable stars using diverse photometric survey sources.Results. We present 99 bona fide CP3 stars, 19 good CP3 star candidates, and seven candidates. Our sample consists of mostly new discoveries and contains, on average, the faintest CP3 stars known (peak distribution 9.5 <= G <= 13.5 mag). All stars are contained within the narrow spectral temperature-type range from B6 to B9.5, in excellent agreement with the expectations and the derived mass estimates (2.4 <= M-circle dot <= 4 for most objects). Our sample stars are between 100 Myr and 500 Myr old and cover the whole age range from zero-age to terminal-age main sequence. They are almost homogeneously distributed at fractional ages on the main sequence <= 80%, with an apparent accumulation of objects between fractional ages of 50% to 80%. We find a significant impact of binarity on the mass and age estimates. Eight photometric variables were discovered, most of which show monoperiodic variability in agreement with rotational modulation.Conclusions. Together with the recently published catalogue of APOGEE CP3 stars, our work significantly increases the sample size of known Galactic CP3 stars, paving the way for future in-depth statistical studies.

Návaznosti

ED3.2.00/08.0144, projekt VaV
Název: CERIT Scientific Cloud