J/other/RAA/15.1671 New carbon stars from LAMOST survey (Si+, 2015)
Identifying carbon stars from the LAMOST pilot survey with the efficient
manifold ranking algorithm.
Si J.-M., Li Y.-B., Luo A.-L., Tu L.-P., Shi Z.-X., Zhang J.-N., Wei P.,
Zhao G., Wu Y.-H., Wu F.-C., Zhao Y.-H.
<Res. Astron. Astrophys., 15, 1671-1694 (2015)>
=2015RAA....15.1671S 2015RAA....15.1671S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, carbon ; Photometry, SDSS ; Photometry, infrared
Keywords: methods: data analysis - methods: statistical - stars: carbon -
binaries - stars: variables
Abstract:
Carbon stars are excellent kinematic tracers of galaxies and can serve
as a viable standard candle, so it is worthwhile to automatically
search for them in a large amount of spectra. In this paper, we apply
the efficient manifold ranking algorithm to search for carbon stars
from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope
(LAMOST) pilot survey, whose performance and robustness are verified
comprehensively with four test experiments. Using this algorithm, we
find a total of 183 carbon stars, and 158 of them are new findings.
According to different spectral features, our carbon stars are
classified as 58 C-H stars, 11 C-H star candidates, 56 C-R stars, ten
C-R star candidates, 30 C-N stars, three C-N star candidates, and four
C-J stars. There are also ten objects which have no spectral type
because of low spectral quality, and a composite spectrum consisting
of a white dwarf and a carbon star. Applying the support vector
machine algorithm, we obtain the linear optimum classification plane
in the J-H versus H-Ks color diagram which can be used to
distinguish C-H from C-N stars with their J-H and H-Ks colors.
In addition, we identify 18 dwarf carbon stars with their relatively
high proper motions, and find three carbon stars with FUV detections
likely have optical invisible companions by cross matching with data
from the Galaxy Evolution Explorer. In the end, we detect four
variable carbon stars with the Northern Sky Variability Survey, the
Catalina Sky Survey and the LINEAR variability databases. According to
their periods and amplitudes derived by fitting light curves with a
sinusoidal function, three of them are likely semiregular variable
stars and one is likely a Mira variable star.
Description:
We analyze the performance of the EMR algorithm with four test
experiments using the SDSS DR8 stellar spectra.
After applying the EMR algorithm, we find a total of 183 carbon stars
from the LAMOST pilot survey, and 158 of them are new findings.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 78 183 The new carbon star catalog
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See also:
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name LAMOST designation (JHHMMSS.ss+DDMMSS.s)
21- 25 F5.2 mag umag ? SDSS u magnitude
27- 31 F5.2 mag gmag ? SDSS g magnitude
33- 37 F5.2 mag rmag ? SDSS r magnitude
39- 43 F5.2 mag imag ? SDSS i magnitude
45- 49 F5.2 mag zmag ? SDSS z magnitude
51- 55 F5.2 mag Jmag ? 2MASS J magnitude
57- 61 F5.2 mag Hmag ? 2MASS H magnitude
63- 67 F5.2 mag Kmag ? 2MASS K magnitude
69- 74 A6 --- SpType MK spectral type (1)
76 A1 --- Note [du] Note (2)
78 A1 --- New [Y/N] Y for new finding
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Note (1): The marker "?" indicates an uncertain observation, and
"CH?", "CN?" and "CR?" indicate possible C-H, C-N and C-R stars respectively.
Note (2): Notes as follows:
d = dC star
u = uncertain observation
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Nov-2015