Derivation of parameters for 3748 FGK stars using H-band spectra from APOGEE Data Release 14

Context. The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed the H-band spectra of over 200 000 stars with R ∼ 22 000. Aims. The main motivation for this work is to test an alternative method to the standard APOGEE pipeline (APOGEE Stellar Parameter and Chemical Abundances Pipeline, ASPCAP) to derive parameters in the near-infrared for FGK dwarfs. Methods. iSpec and Turbospectrum are used to generate synthetic spectra matching APOGEE observations and to determine the parameters through χ2 minimization. Results. We present spectroscopic parameters (Teff, [M/H], log g, vmic) for a sample of 3748 main-sequence and subgiant FGK stars, obtained from their APOGEE H-band spectra. Conclusions. We compare our output parameters with the ones obtained with ASPCAP for the same stellar spectrum, and find that the values agree within the expected uncertainties. A comparison with the optical samples California Planet Survey, High Accuracy Radial Velocity Planet Searcher – Guaranteed Time Observations, and PASTEL is also available, and median differences below 10 K for Teff and 0.2 dex for [M/H] are found. Reasons for these differences are explored. The full H-band line list, the line selection for the synthesis, and the synthesized spectra are available at the CDS, as are the calculated parameters and their estimated uncertainties.

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Structure and dynamics of the Milky Way disk as revealed from the radial velocity distributions of APOGEE red clump stars

Proceedings of the International Astronomical Union ◽

10.1017/s174392131601173x ◽

2016 ◽

Vol 11 (S321) ◽

pp. 50-50

Author(s):

Daisuke Toyouchi ◽

Masashi Chiba

Keyword(s):

Near Infrared ◽

Milky Way ◽

Radial Velocities ◽

Galactocentric Distance ◽

Chemical Abundances ◽

Structure And Dynamics ◽

Evolution Experiment ◽

Dynamical Properties ◽

Red Clump ◽

Independent Work

AbstractWe investigate the structure and dynamics of the Milky Way (MW) disk stars based on the analysis of the Apache Point Observatory Galactic Evolution Experiment (APOGEE) data, to infer the past evolution histories of the MW disk component(s) possibly affected by radial migration and/or satellite accretions. APOGEE is the first near-infrared spectroscopic survey for a large number of the MW disk stars, providing their radial velocities and chemical abundances without significant dust extinction effects. We here adopt red-clump (RC) stars (Bovy et al. 2014), for which the distances from the Sun are determined precisely, and analyze their radial velocities and chemical abundances in the MW disk regions covering from the Galactocentric distance, R, of 5 kpc to 14 kpc. We investigate their dynamical properties, such as mean rotational velocities, 〈Vφ〉 and velocity dispersions, as a function of R, based on the MCMC Bayesian method. We find that at all radii, the dynamics of alpha-poor stars, which are candidates of young disk stars, is much different from that of alpha-rich stars, which are candidates of old disk stars. We find that our Jeans analysis for our sample stars reveals characteristic spatial and dynamical properties of the MW disk, which are generally in agreement with the recent independent work by Bovy et al. (2015) but with a different method from ours.

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Discovery of Infrared Stars in Globular Clusters in the Magellanic Clouds and Their Light Variations

Highlights of Astronomy ◽

10.1017/s1539299600021456 ◽

1998 ◽

Vol 11 (1) ◽

pp. 395-395

Author(s):

S. Nishida ◽

T. Tanabé ◽

S. Matsumoto ◽

T. Onaka ◽

Y. Nakada ◽

...

Keyword(s):

Mass Loss ◽

Globular Clusters ◽

Main Sequence ◽

Near Infrared ◽

Magellanic Clouds ◽

Infrared Light ◽

Agb Stars ◽

Dust Shells ◽

Infrared Stars ◽

Infrared Survey

A systematic near-infrared survey was made for globular clusters in the Magellanic Clouds. Two infrared stars were discovered in NGC419 (SMC) and NGC1783 (LMC). NGC419 and NGC1783 are well-studied rich globular clusters whose turn-off masses and ages are estimated MTO ~ 2.0 Mʘ and т ~1.2 Gyr for NGC419, and MT0 ~ 2.0 Mʘ and т ʘ 0.9 Gyr for NGC1783, respectively. The periods of the infrared light variations were determined to be 540 dfor NGC419IR1 and to be 480 d for NGC1783IR1, respectively. Comparison of the measurements with the period—if magnitude relation for carbon Miras in the LMC by Groenewegen and Whitelock(1996) revealed that the Kmagnitudes of the infrared stars were fainter by about 0.3 — 0.8 magnitude than those predicted by the P — K relation. This deviation can be explained if the infrared stars are surrounded by thick dust shells and are obscured even in the K band. The positions of NGC419IR1and NGC1783IR1 on the P — K diagram suggest that AGB stars with the main sequence masses of about 2 Mʘ start their heavy mass-loss when P ʘ 500 d.

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Near Infrared Feature Waveband Selection for Fishmeal Quality Assessment by Frequency Adaptive Binary Differential Evolution

Chemometrics and Intelligent Laboratory Systems ◽

10.1016/j.chemolab.2021.104393 ◽

2021 ◽

pp. 104393

Author(s):

Youyou Zhang ◽

Huazhou Chen ◽

Weihao Chen ◽

Lili Xu ◽

Chunting Li ◽

...

Keyword(s):

Differential Evolution ◽

Quality Assessment ◽

Near Infrared ◽

Selection For ◽

Binary Differential Evolution

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Wavelength selection for near-infrared reflectance moisture meters

Journal of Agricultural Engineering Research ◽

10.1016/0021-8634(91)80032-a ◽

1991 ◽

Vol 49 ◽

pp. 113-125 ◽

Cited By ~ 28

Author(s):

C.R. Bull

Keyword(s):

Near Infrared ◽

Infrared Reflectance ◽

Wavelength Selection ◽

Near Infrared Reflectance ◽

Selection For

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Variable Selection for Partial Least-Squares Calibration of Near-Infrared Data from Orthogonally Designed Experiments

Applied Spectroscopy ◽

10.1366/0003702021954692 ◽

2002 ◽

Vol 56 (3) ◽

pp. 337-345 ◽

Cited By ~ 1

Author(s):

S. Kamaledin Setarehdan ◽

John J. Soraghan ◽

David Littlejohn ◽

Daran A. Sadler

Keyword(s):

Variable Selection ◽

Least Squares ◽

Partial Least Squares ◽

Near Infrared ◽

Designed Experiments ◽

Selection For ◽

Infrared Data

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Variable selection for near-infrared spectrum modeling based on fast nondominated sorting genetic algorithm

Spectroscopy Letters ◽

10.1080/00387010.2021.1980403 ◽

2021 ◽

pp. 1-13

Author(s):

Hubin Liu ◽

Chao Wang ◽

Ge Wang ◽

Weijie Xu ◽

Longlian Zhao ◽

...

Keyword(s):

Genetic Algorithm ◽

Variable Selection ◽

Infrared Spectrum ◽

Near Infrared ◽

Spectrum Modeling ◽

Selection For ◽

Nondominated Sorting ◽

Near Infrared Spectrum

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Identification of Natural Bamboo Fibers and Flax Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.153 ◽

2013 ◽

Vol 821-822 ◽

pp. 153-157 ◽

Cited By ~ 1

Author(s):

Wei Dong Li ◽

Xin Hou Wang ◽

Li Hua Peng

Keyword(s):

Cluster Analysis ◽

Fourier Transform ◽

Near Infrared ◽

Hierarchical Cluster ◽

High Accuracy ◽

Flax Fibers ◽

First Derivative ◽

Near Infrared Spectra ◽

Bamboo Fibers ◽

The Fourier Transform

In this paper, the method based on the testing of the Fourier transform near infrared (NIR) spectra is proposed to identify natural bamboo fibers and flax fibers. The discrimination models between natural bamboo fibers and flax fibers are established by means of Ward’s algorithm and Hierarchical Cluster Analysis after the first derivative and vector normalization pretreatment. The verification results indicated that these two kinds of fibers could be classified into two separated groups for the identification and the near infrared spectra model is high accuracy.

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The low-mass pre-main sequence population of Scorpius OB1

Astronomy and Astrophysics ◽

10.1051/0004-6361/201730960 ◽

2018 ◽

Vol 615 ◽

pp. A148 ◽

Cited By ~ 10

Author(s):

Francesco Damiani

Keyword(s):

Total Mass ◽

Main Sequence ◽

Near Infrared ◽

Large Population ◽

X Ray ◽

Uv Excess ◽

Low Mass ◽

Ob Associations ◽

The Rich ◽

A New Technique

Context. The low-mass members of OB associations, expected to be a major component of their total population, are in most cases poorly studied because of the difficulty of selecting these faint stars in crowded sky regions. Our knowledge of many OB associations relies on only a relatively small number of massive members. Aims. We study here the Sco OB1 association, with the aim of a better characterization of its properties, such as global size and shape, member clusters and their morphology, age and formation history, and total mass. Methods. We use deep optical and near-infrared (NIR) photometry from the VPHAS+ and VVV surveys, over a wide area (2.6° × 2.6°), complemented by Spitzer infrared (IR) data, and Chandra and XMM-Newton X-ray data. A new technique is developed to find clusters of pre-main sequence M-type stars using suitable color-color diagrams, complementing existing selection techniques using narrow-band Hα photometry or NIR and ultraviolet (UV) excesses, and X-ray data. Results. We find a large population of approximately 4000 candidate low-mass Sco OB1 members whose spatial properties correlate well with those of Hα-emission, NIR-excess, UV-excess, and X-ray detected members, and unresolved X-ray emission. The low-mass population is spread among several interconnected subgroups: they coincide with the HII regions G345.45+1.50 and IC4628, and the rich clusters NGC 6231 and Trumpler 24, with an additional subcluster intermediate between these two. The total mass of Sco OB1 is estimated to be ~ 8500 M⊙. Indication of a sequence of star-formation events is found, from South (NGC 6231) to North (G345.45+1.50). We suggest that the diluted appearance of Trumpler 24 indicates that the cluster is now dissolving into the field, and that tidal stripping by NGC 6231 nearby contributes to the process.

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