Near infrared spectrograph

Baraga JJ, Feld MS, Rava RR Rapid near-infrared Raman-spectroscopy of human tissue with a spectrograph and CCD detector. Applied Spectroscopy 1992, 46, 187-190. 

Major technological and scientific innovation in the past 10 to 15 years has significantly broadened the applicability of Raman spectroscopy, particularly in chemical analysis. Fourier transform (FT)-Raman, charge-coupled device (CCD) detectors, compact spectrographs, effective laser rejection filters, near-infrared lasers, and small computers have contributed to a revolution in Raman instrumentation and made routine analytical applications possible. An increase in instrumental sensitivity by factors as large as 10, plus decreases in both interferences and noise resulted from this revolution. The number of vendors of Raman spectrometers increased from 3 to 12 over a 10-year period, and integrated commercial spectrometers led to turnkey operation and robust reliability. 

R. P. Rava et al., Rapid Near-Infrared Raman Spectroscopy of Human Tissue with a Spectrograph and CCD Detector, Appl. Spectrosc., 46(2), 187 (1992). 

Dispersive elements and interferometers are widely used in vibrational microspectroscopy. As in bulk measurements, microscopic Raman studies are carried out with grating monochromators, spectrographs, or Fourier transform spectrometers, although Fourier transform instruments are usually limited to applications in the near-infrared spectral region. Infrared microspectroscopy, by contrast, is almost exclusively a Fourier transform technique. 

Optical emission spectroscopy includes the observation of flame-, arc-, and spark-induced emission phenomena in the ultraviolet, visible, and near infrared regions of the electromagnetic spectrum [38]. Qualitative and quantitative information can be gained from the intensity of the characteristic emission wavelengths. Analysis of lead in environmental samples (e.g., soils, rocks, and minerals) may be performed reproducibly down to the 5 ppm level. Emission spectroscopy is best used for the multi-elemental analysis of samples, because of the high cost of equipment. Usually, single element analyses are not performed on a emission spectrograph. 

Atmospheres of extraterrestrial planets can be directly studied during a transit. Two transit events with the Near Infrared Camera and Multi Object Spectrograph (NIC-MOS) camera on the Hubble Space Telescope (HST) were observed for the object GJ 436 b. In order to detect the atmosphere, high-cadence time series of prism spectra covering the 1.1-1.9 pm spectral range were analyzed (Pont et al., 2009 [266]). This object is an extrasolar hot Neptune. The authors measured a flat transmission spectrum at the level of a few parts per 10000 in flux, with no significant signal in the 1.4 pm water band. 

Abstract. ISIS IR is the first attempt to use fibre optics for near infrared ectroscopy (A < 1.8/tm). It is a field spectrograph (2D ectroscopy), and can work at various resolving powers (up to 25000). It can be transported anjrwhere, and soon it will be used at CFHT with one NICMOS 3-based camera. 

A NICMOS-3 BASED SPECTROGRAPH FOR NEAR INFRARED ASTRONOMY... 

The first instrument we plan to buUd for the AEOS telescope is a combination of a simple near-infrared camera with limited grism spectroscopic capability and a low-resolution optical spectrograph equipped with a slitviewing optical CCD camera. This system will thus provide the basic tools for foUow-on studies of surveys, while stiU being simple enough for an astronomical commissioning instrument for the AEOS telescope. The instrument... 

The NASA Infrared Telescope Facility Cryogenic Echelle Spectrograph (CSHELL see Greene et al. 1993) is a new near-infrared instrument which h2is adequate sensitivity, spatial, and spectral resolution to advance our observational knowledge of the morphologies and kinematics of outflows. 

The most accurate measurements of the CMB spectrum to date have come from the Far InfraRed Absolute Spectrophotometer (FIRAS) on the COsmic Background Explorer (COBE) (Boggess et al., 1992). In contradiction to its name, FIRAS was a fully differential spectrograph that only measured the difference between the sky and an internal reference source that was very nearly a blackbody. Figure 9.2 shows the interferograms observed by FIRAS for the sky and for the external calibrator (XC) at three different temperatures, all taken with the internal calibrator (IC) at 2.759 K. Data from the entire FIRAS dataset show that the rms deviation from a blackbody is only 50 parts per million of the peak Iv of the blackbody (Fixsen et al., 1996) and a recalibration of the thermometers on the external calibrator yield a blackbody temperature of... 

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