Near infrared spectroscopy of protostars

1981 ◽  
Vol 303 (1480) ◽  
pp. 487-496
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Gas Dynamics ◽  
Near Infrared ◽  
Molecular Gas ◽  
Orion Nebula ◽  
Ionized Gas ◽  
Physical Conditions ◽  
Vibrational Bands ◽  
Optical Wavelengths

Observational study of protostars and their immediate environs has recently become possible as a result of advances in infrared spectroscopy, especially in the near infrared (A = 2—5 pm). Although such stars are totally obscured at optical wavelengths by the enshrouding dust and gas from which they formed, the near infrared spectroscopy has yielded detection of emission lines from both ionized gas and high excitation molecular gas ( T >2000 K) probably within a few astronomical units of several such sources (e.g. the BN object in the Orion nebula). The former lines provide the first constraints on the spectral type and temperature of the protostar; the latter reveal the physical conditions (density and temperature) and gas dynamics in the immediate protostellar nebula. . Data on the BN object covering the CO, 13 CO, and H 2 vibrational bands and the H II lines are presented as an illustration of these techniques.

Nondestructive Measurement of the Subsurface Structure of Biological Material Having Cellular Structure by Using Near-Infrared Spectroscopy

1996 ◽  
Vol 50 (9) ◽  
pp. 1117-1124 ◽  
Author(s):  
Satoru Tsuchikawa ◽  
Kazuo Hayashi ◽  
Shigeaki Tsutsumi
Keyword(s):  
Surface Roughness ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Cellular Structure ◽  
Near Infrared ◽  
Incident Light ◽  
Physical Conditions ◽  
Light Passing ◽  
Nir Light ◽  
Reflected Light

Biological materials–wood is a typical example–are widely used in a state where not only the cellular structure but also its bulky shape is retained. NIRS (near-infrared spectroscopy) may be called for as a promising technique to analyze the physical state of such materials as well as the chemical composition. In this report, the effects of physical conditions found in wood on the absorption of NIR radiation are examined. In the experiments, conifers (Sitka spruce) that had various degrees of surface roughness and different orientations of fibers to the direction of incident light were used. Results of these measurements showed that the orientation of fibers and the surface roughness of wood were directly related to the absorbance. In addition, it became clear that the behavior of diffusely reflected light in wood could be expressed by Kubelka–Munk theory and fell into three categories according to the characteristic of the absorption and scattering coefficient. On the basis of these results, a new concept for the behavior of NIR light passing through material made of hollow fibers has been proposed.

scholarly journals Near-Infrared Spectroscopy of the Diffuse Galactic Emission

2012 ◽  
Vol 10 (H16) ◽  
pp. 703-704
Author(s):  
T. Onaka ◽  
I. Sakon ◽  
R. Ohsawa ◽  
T. I. Mori ◽  
H. Kaneda ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Interstellar Medium ◽  
Near Infrared Spectroscopy ◽  
Emission Band ◽  
Near Infrared ◽  
Infrared Camera ◽  
Nir Spectroscopy ◽  
Ionized Gas ◽  
Band Ratio ◽  
Galactic Emission

AbstractThe near-infrared (NIR) spectral range (2–5 μm) contains a number of interesting features for the study of the interstellar medium. In particular, the aromatic and aliphatic components in carbonaceous dust can be investigated most efficiently with the NIR spectroscopy. We analyze NIR spectra of the diffuse Galactic emission taken with the Infrared Camera onboard AKARI and find that the aliphatic to aromatic emission band ratio decreases toward the ionized gas, which suggests processing of the band carriers in the ionized region.

Near-infrared spectroscopy (NIRS) – a promising brain imaging method in Psychiatry?

2008 ◽  
Vol 39 (01) ◽  
Author(s):  
AJ Fallgatter ◽  
AC Ehlis ◽  
MM Richter ◽  
M Schecklmann ◽  
MM Plichta
Keyword(s):  
Infrared Spectroscopy ◽  
Brain Imaging ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Imaging Method

A Study of Frontal Signals in Brain Computer Interfaces: Interpretation of EEG & FNIRS

2020 ◽  
pp. 136-142
Author(s):  
S. Srilekha ◽  
B. Vanathi
Keyword(s):  
Infrared Spectroscopy ◽  
Healthy Subject ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Economic Conditions ◽  
Brain Computer Interfaces ◽  
Functional Near Infrared Spectroscopy ◽  
Computer Interfaces ◽  
Rehabilitation Devices

This paper focuses on electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) comparison to help the rehabilitation patients. Both methods have unique techniques and placement of electrodes. Usage of signals are different in application based on the economic conditions. This study helps in choosing the signal for the betterment of analysis. Ten healthy subject datasets of EEG & FNIRS are taken and applied to plot topography separately. Accuracy, Sensitivity, peaks, integral areas, etc are compared and plotted. The main advantages of this study are to prompt their necessities in the analysis of rehabilitation devices to manage their life as a typical individual.

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