2021
New mercury-manganese stars and candidates from LAMOST DR4
PAUNZEN, Ernst; S. HUMMERICH a K. BERNHARDZákladní 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 |
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