54 citations · 410 across the 27 of their papers we have counts for
13 papers · 1 filter
Effective temperatures of classical Cepheids from line-depth ratios in the H-band
V. Kovtyukh, B. Lemasle, N. Nardetto +6
The technique of line depth ratios (LDR) is one of the methods to determine the effective temperature of a star. They are crucial in the spectroscopic studies of variable stars lik…
Astrophysical calibration of the oscillator strengths of YJ-band absorption lines in classical Cepheids
S. S. Elgueta, N. Matsunaga, M. Jian +13
Newly-developed spectrographs with increased resolving powers, particularly those covering the near-IR range, allow the characterization of more and more absorption lines in stella…
Absorption Lines in the 0.91-1.33 m Spectra of Red Giants for Measuring Abundances of Mg, Si, Ca, Ti, Cr, and Ni
K. Fukue, N. Matsunaga, S. Kondo +13
Red giants show a large number of absorption lines in both optical and near-infrared wavelengths. Still, the characteristics of the lines in different wave passbands are not necess…
Effective temperatures of red supergiants estimated from line-depth ratios of iron lines in the YJ bands, 0.97--1.32 micron
Daisuke Taniguchi, Noriyuki Matsunaga, Mingjie Jian +10
Determining the effective temperatures (Teff) of red supergiants (RSGs) observationally is important in many fields of stellar physics and galactic astronomy, yet some significant…
The effect of surface gravity on line-depth ratios in the wavelength range 0.97-1.32 μm
Mingjie Jian, Daisuke Taniguchi, Noriyuki Matsunaga +10
A line-depth ratio (LDR) of two spectral lines with different excitation potentials is expected to be correlated with the effective temperature (). It is possible t…
Identification of Absorption Lines of Heavy Metals in the Wavelength Range 0.97--1.32 Micron
Noriyuki Matsunaga, Daisuke Taniguchi, Mingjie Jian +13
Stellar absorption lines of heavy elements can give us various insights into the chemical evolution of the Galaxy and nearby galaxies. Recently developed spectrographs for the near…
Possible progression of mass flow processes around young intermediate-mass stars based on high-resolution near-infrared spectroscopy. I. Taurus
Chikako Yasui, Satoshi Hamano, Kei Fukue +12
We used the WINERED spectrograph to perform near-infrared high-resolution spectroscopy (resolving power ,000) of 13 young intermediate-mass stars in the Taurus star-forming…
FeI lines in 0.91-1.33 m spectra of red giants for measuring the microturbulence and metallicities
Sohei Kondo, Kei Fukue, Noriyuki Matsunaga +16
For a detailed analysis of stellar chemical abundances, high-resolution spectra in the optical have mainly been used, while the development of near-infrared (NIR) spectrograph has…
The metallicity effect on line-depth ratios in APOGEE -band spectra
Mingjie Jian, Noriyuki Matsunaga, Kei Fukue
Ratios of carefully selected line depths are sensitive to stellar effective temperature (). Relations established between line-depth ratio (LDR) and $T_\mathrm{eff}…
WINERED high-resolution near-infrared line catalog: A-type star
H. Sameshima, Y. Ikeda, N. Matsunaga +13
We present a catalog of absorption lines in the z', Y, and J bands that we identified in 21 Lyn, a slowly rotating A0.5 V star. We detected 155 absorption features in the high-reso…
A newly-identified emission-line region around P Cygni
Misaki Mizumoto, Naoto Kobayashi, Satoshi Hamano +12
We present a high-resolution () near-infrared (9,100-13,500 ) long-slit spectrum of P Cygni obtained with the newly commissioned WINERED spectrograph in Japan.…
On the chemical abundances of Miras in clusters: V1 in the metal-rich globular NGC 5927
V. D'Orazi, D. Magurno, G. Bono +50
We present the first spectroscopic abundance determination of iron, alpha-elements (Si, Ca and Ti) and sodium for the Mira variable V1 in the metal-rich globular cluster NGC 5927.…
Method to Estimate the Effective Temperatures of Late-Type Giants using Line-Depth Ratios in the Wavelength Range 0.97-1.32m
Daisuke Taniguchi, Noriyuki Matsunaga, Naoto Kobayashi +7
The effective temperature, one of the most fundamental atmospheric parameters of a star, can be estimated using various methods, and here we focus on the method using line-depth ra…