THE GEMINI SPECTRAL LIBRARY OF NEAR-IR LATE-TYPE STELLAR TEMPLATES AND ITS APPLICATION FOR VELOCITY DISPERSION MEASUREMENTS

Based on a theoretical approach, new for evanescent wave spectroscopy, it has been shown that the dispersion properties of higher modes of a multimode chalcogenide fiber partially immersed in an absorbing medium can be used to create fiber devices that combine the functions of a supercontinuum generator and a sensing element of a spectroscopic sensor of the mid-IR range. The propagation of radiation in higher modes will allow one to control the position of the group velocity dispersion zero and to obtain a supercontinuum pumped in the near IR range. In the sensing element, the use of higher-order evanescent modes will allow for greater sensitivity and broaden the dynamic range of the sensor.

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Near-IR Surface Photometry of 400 Late-type Galaxies

Spiral Galaxies in the Near-IR - ESO Astrophysics Symposia ◽

10.1007/978-3-540-49739-4_31 ◽

1996 ◽

pp. 214-215

Author(s):

Daniele Pierini ◽

Giuseppe Gavazzi

Keyword(s):

Surface Photometry ◽

Late Type ◽

Near Ir

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Space Distribution of Red Giants and the Galactic Structure

International Astronomical Union Colloquium ◽

10.1017/s0252921100106682 ◽

1984 ◽

Vol 78 ◽

pp. 257-260

Author(s):

K. Ishida

Keyword(s):

Galactic Structure ◽

Space Distribution ◽

Red Giants ◽

Stellar Content ◽

Late Type ◽

Ir Radiation ◽

Near Ir ◽

The Galaxy ◽

K Band

AbstractStellar content contributing to near IR radiation do not show radial differentiation in the Galaxy. Late-type giants and supergiants supply about 70% of the total volume emissivity at the K band, in the solar vicinity within 1 kpc, and also at the distance of several kpc in the Scutum region.

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Environmental dependence of SFRs in late-type GAMA galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312009404 ◽

2011 ◽

Vol 7 (S284) ◽

pp. 352-356

Author(s):

Meiert W. Grootes ◽

Richard J. Tuffs ◽

Ellen Andrae ◽

Lee S. Kelvin ◽

Jochen Liske ◽

...

Keyword(s):

Velocity Dispersion ◽

Mass Function ◽

Radiative Transfer Model ◽

Transfer Model ◽

Late Type ◽

Initial Application ◽

Gas Consumption ◽

Group Members ◽

Attenuation Corrected ◽

Environmental Dependence

AbstractPresent and past gas-fuelling of galaxies is expected to depend upon both the properties of the galaxies themselves, as well as their larger-scale environments. In the case of galaxies in groups the environment, i.e the group mass, can be probed by measuring the velocity dispersion of the group members, as done with the GAMA Galaxy Group catalogue (Robotham et al. 2011), probing the halo mass function all the way to small groups. The gas-fuelling rate of normal late-type galaxies can be traced by the SFR under the assumption of a steady state between gas-fuelling and gas-consumption by SF. We present a method to estimate disk opacities from UV/optical photometric characteristics, calibrated using the radiative transfer model of Popescu et al. (2011), applied to UV-Opt-FIR GAMA/H-ATLAS photometry for a subset of GAMA galaxies. We use the method to extract attenuation corrected SFRs for a large sample of late-type GAMA galaxies, which we use in an initial application to constrain the dependency of star formation/gas-fuelling in late-type galaxies on mass of parent DMH, and compactness of galaxy group.

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Identification of Electrolytes in Aqueous Solutions from Near-IR Spectra

Applied Spectroscopy ◽

10.1366/0003702963906096 ◽

1996 ◽

Vol 50 (4) ◽

pp. 444-448 ◽

Cited By ~ 18

Author(s):

Jie Lin ◽

Jing Zhou ◽

Chris W. Brown

Keyword(s):

Aqueous Solutions ◽

Ir Spectra ◽

Principal Component Regression ◽

Principal Component ◽

Transition Metal Ions ◽

Water Molecules ◽

Spectral Library ◽

Dipole Interactions ◽

Near Ir ◽

Solutions Of Electrolytes

Dissolution of electrolytes causes characteristic changes in the near-IR spectrum of water. These changes result from a decrease in the concentration of water; charge-dipole interactions between ions and water molecules; formation of hydrogen bonds between oxygen or nitrogen atoms in some ions and water molecules; production of H+ and OH− ions from dissociation and hydrolysis; absorptions due to OH, NH, and CH groups in some ions; and intrinsic colors of some transition metal ions. Changes in spectra were used for identification of electrolytes in aqueous solutions. Near-IR spectra of 71 solutions of single electrolytes were measured and used to develop a spectral library. This near-IR spectral library was processed with principal component regression (PCR) and used for the identification of single and multiple electrolytes in aqueous solutions with the use of their spectra. Most of the unknown electrolytes were identified correctly. For the others, very similar electrolytes were selected with one ion identified correctly. The near-IR spectral library of aqueous solutions of electrolytes can be used as a simple and fast approach for the identification of electrolytes.

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Mass-Loss from Late-Type Stars: New Observational Evidence

Symposium - International Astronomical Union ◽

10.1017/s0074180900093797 ◽

1983 ◽

Vol 103 ◽

pp. 292-292

Author(s):

P. G. Wannier ◽

R. Sahai

Keyword(s):

Mass Loss ◽

Central Star ◽

Ir Absorption ◽

Late Type ◽

Ir Radiation ◽

Loss Mechanism ◽

Continuum Source ◽

Near Ir ◽

Molecular Lines ◽

Circumstellar Shells

Rapid mass-loss is observed in many late-type stars, yet the mass-loss mechanisms operating are not well understood. A survey of molecular emission from circumstellar shells has been carried out using millimeterwave molecular lines and suggests that radiation pressure alone may be inadequate to explain the observed mass-loss, especially in the case of carbon-rich objects which may display rates in excess of 10−5 M⊙/yr. Recent near-IR molecular line observations provide evidence for ejected material at several different velocities along the line-of-sight and may indicate the additional mass-loss mechanism at work. Resonantly scattered IR radiation spatially displaced from the central IR continuum source has now been observed for the first time and sheds new light on the IR absorption-line results, providing information about material within 1016 cm of the central star. These results are discussed along with recent high-resolution millimeterwave observations.

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EEV and Electron Corp. Virtual Phase CCDs in the Near IR Region, He I λ 10830 Å

Symposium - International Astronomical Union ◽

10.1017/s0074180900056837 ◽

1995 ◽

Vol 167 ◽

pp. 367-368

Author(s):

A. G. Shcherbakov ◽

Z. A. Shcherbakova ◽

I. Ilyin ◽

I. Tuominen

Keyword(s):

High Resolution ◽

Point Source ◽

Line Profile ◽

The Sun ◽

Late Type ◽

Coronal Emission ◽

Near Ir

He I, λ 10830 å observations of late-type stars provide valuable information about the chromospheric and low chromospheric-coronal transition regions. High resolution measurements of the helium λ 10830 å line profile offer a convenient way to survey the coronal emission of the Sun as a point source, as well as a variety of stars (O'Brien and Lambert, 1986, Shcherbakov and Shcherbakova, 1991).

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Spiral galaxies in the SAURON survey

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308017894 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 271-276

Author(s):

Reynier F. Peletier ◽

Katia Ganda ◽

Jesús Falcón-Barroso ◽

Roland Bacon ◽

Michele Cappellari ◽

...

Keyword(s):

Radial Velocity ◽

Velocity Dispersion ◽

Spiral Galaxies ◽

Line Strength ◽

Early Type ◽

Late Type ◽

Integral Field Spectroscopy ◽

Field Spectroscopy ◽

New Ideas ◽

Integral Field

AbstractWe discuss some recent integral field spectroscopy using the SAURON instrument of a sample consisting of 24 early-type spirals, part of the SAURON Survey, and 18 late-type spirals. Using 2-dimensional maps of their stellar radial velocity, velocity dispersion, and absorption line strength, it is now much easier to understand the nature of nearby galactic bulges. We discuss a few highlights of this work, and point out some new ideas about the formation of galactic bulges.

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The Galactic Distribution and Kinematics of OH Stars (A Preliminary Discussion)

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000014314 ◽

1975 ◽

Vol 2 (6) ◽

pp. 362-363

Author(s):

P.F. Bowers

Keyword(s):

Large Scale ◽

Velocity Dispersion ◽

Neutral Hydrogen ◽

Late Type ◽

Velocity Range ◽

Hydrogen Distribution ◽

Mira Variables ◽

Sky Survey ◽

Ir Stars ◽

Galactic Distribution

The majority of OH/IR stars have been identified as M-type Mira variables, but there are a few cases where the stars have been identified as M supergiants or late-type semi-regular variables. A large number of OH sources have also been discovered with the 1612 MHz OH characteristics of OH/IR stars but no apparent optical or infrared counterparts. In several cases the velocities of these unidentified sources (OH stars) have been outside the velocity range of the neutral hydrogen distribution, suggesting that some of these sources may represent a population with a higher velocity dispersion than Population I objects (Kerr and Bowers 1974a, b). The lack of infrared and optical counterparts may indicate that the sources are quite distant, since identified OH/IR stars are often bright infrared objects. A large-scale 1612 MHz sky survey has therefore been initiated to study the galactic distribution and kinematics of the OH stars and to investigate the possibility that they may represent an older population of stars (Bowers et al. 1974).

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The Cluster NGC 330 in the SMC: Radial Velocities of Individual Stars

Symposium - International Astronomical Union ◽

10.1017/s007418090009210x ◽

1980 ◽

Vol 85 ◽

pp. 339-339

Author(s):

M. W. Feast ◽

C. Black

Keyword(s):

Standard Deviation ◽

Main Sequence ◽

Velocity Dispersion ◽

Radial Velocities ◽

Spectroscopic Binaries ◽

Early Type ◽

Late Type ◽

Main Sequence Stars ◽

Image Tube ◽

Cloud Clusters

Radial velocities based on 81 image tube spectra at 30 Å mm−1 are given for 25 stars (17 early type supergiants or upper main sequence stars and 8 late type stars) in the young SMC cluster NGC 330. An upper (one standard deviation) limit to the velocity dispersion is found to be 2 km s−1. The mass-to-light ratio is likely to be less than 0.1 in solar units. Results for other young Magellanic Cloud clusters derived on the assumption that they are tidally limited are consistent with this result. Spectroscopic binaries with semi-amplitudes, K, greater than about 10 km s−1 appear to be rare or absent amongst the stars studied.

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