J/MNRAS/449/1401 Am stars candidates from LAMOST DR1 (Hou+, 2015)
A large sample of metallic-line star candidates from LAMOST Data Release 1.
Hou W., Luo A., Yang H., Wei P., Zhao Y., Zuo F., Song Y., Du B., Bai Z.,
Zhang Y., Hou Y., Liu X.
<Mon. Not. R. Astron. Soc., 449, 1401-1407 (2015)>
=2015MNRAS.449.1401H 2015MNRAS.449.1401H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, A-type ; Stars, Am ; Stars, F-type
Keywords: methods: data analysis - stars: chemically peculiar -
stars: early-type
Abstract:
We present a sample of metallic-line star (Am) candidates from the
Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST)
Data Release One (DR1). According to the characteristic of
underabundance of calcium and overabundance of iron element of Am
stars, we propose an empirical separation curve derived from line
indices of Ca ii K line and iron lines we choose for low-resolution
spectra. Ultimately, 3537 Am candidates are selected from more than
30000 stars, which are classified as A-type or early F-type stars by
both the LAMOST pipeline and visual inspection. Then, we carry out
some analysis on this sample and finally provide a list of the Am
candidates with 10 relevant parameters. Compared with other
catalogues, Am candidates selected from the LAMOST DR1 are much
fainter on the whole. Obviously, our list is an important complement
to already known bright Am catalogues, and it offers valuable material
for research on this type of chemically peculiar star.
Description:
In this paper, we present a large sample of Am star candidates taken
from the Large Sky Area Multi-Object Fibre Spectroscopic Telescope
(LAMOST) Data Release One (DR1).
The LAMOST DR1, based on both a year of pilot survey from 2011 October
to 2012 June and the first year of the general survey from 2012
September to 2013 June, contains more than two million spectra with
limiting magnitude down to V∼19.5mag (Luo et al.
2012RAA....12..1243L).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4l.dat 84 221 List with low reliability
table4m.dat 84 3316 *Major list
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Note on table4m.dat: The sample of Am candidates from LAMOST ultimately
contains 3258 candidates.
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See also:
III/260 : General Catalogue of Ap and Am stars (Renson+ 2009)
Byte-by-byte Description of file: table4l.dat table4m.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq [1/3316] Sequential number
5 A1 --- n_Seq [*] Note on Seq (1)
7- 25 A19 --- Name Designation of target in LAMOST
(JHHMMSS.ss+DDMMSS.s)
27- 37 F11.7 deg RAdeg Right ascension (J2000)
39- 48 F10.7 deg DEdeg Declination (J2000)
50- 59 F10.8 --- Conf [0/1] Confidence for Am type (2)
61- 66 F6.3 mag Vmag ?=99.999 V magnitude
68- 69 A2 --- KType K line type (3)
71- 72 A2 --- MType Metallic-line type from CaII K line (3)
74- 78 F5.3 [cm/s2] logg ?=9.999 Surface gravity
80- 84 F5.3 [cm/s2] e_logg ?=9.999 rms uncertainty on logg
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Note (1): * for objects also contained in the catalogue of Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat. III/260)
Note (2): The possibility of one star being an Am star is low when the value is
near 0, and high for a value near 1.
Note (3): From the perspective of MK classification, classical Am stars are the
metallic-line stars whose difference between K line type and metallic-line
type is at least five subtypes, which is designated as Am.
Marginal Am stars for which the difference of spectral type is less than
five subtypes are designated as Am:.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 10-Nov-2015