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Atmosphere window region

Atmospheric windows Regions of the electromagnetic spectrum that allow radiation to pass through the atmosphere to reach the ground. [Pg.307]

Figure 9. Quantum efficiency of a Rockwell 2Kx2K HAWAII array. The atmospheric windows of I, H, and K are shown. Note the relatively constant QE across the 1-2.5 p,m wavelength region, with peak QE of 84% in the K-band (centered at 2.2 /um). Eigure courtesy of J. Garnett, Rockwell Scientific. Figure 9. Quantum efficiency of a Rockwell 2Kx2K HAWAII array. The atmospheric windows of I, H, and K are shown. Note the relatively constant QE across the 1-2.5 p,m wavelength region, with peak QE of 84% in the K-band (centered at 2.2 /um). Eigure courtesy of J. Garnett, Rockwell Scientific.
Rotational spectroscopy and microwave astronomy are the most accurate way to identify a molecule in space but there are two atmospheric windows for infrared astronomy in the region 1-5 im between the H2O and CO2 absorptions in the atmosphere and in the region 8-20 xrn. Identification of small molecules is possible by IR but this places some requirements on the resolution of the telescope and the spacing of rotational and vibrational levels within the molecule. The best IR telescopes, such as the UK Infrared Telescope on Mauna Kea in Hawaii (Figure 3.13), are dedicated to the 1-30 xm region of the spectrum and have a spatial resolution very close to the diffraction limit at these wavelengths. [Pg.71]

Fig. 13. Attenuation of electromagnetic radiation in the atmosphere. The solid curve indicates the altitude where the intensity of the external radiation is reduced to 1/2 of its original value at a given wavelength (after Giacconi et al., 1968). Physical phenomena and observational techniques are indicated for the different wavelength regions. All observed interstellar radio frequency lines lie within the atmospheric windows... Fig. 13. Attenuation of electromagnetic radiation in the atmosphere. The solid curve indicates the altitude where the intensity of the external radiation is reduced to 1/2 of its original value at a given wavelength (after Giacconi et al., 1968). Physical phenomena and observational techniques are indicated for the different wavelength regions. All observed interstellar radio frequency lines lie within the atmospheric windows...
Contrary to all the laser lines reported in Table 4, lasing at 3.9 /tm with ZBLAN Ho3+ fiber is achieved at liquid-nitrogen temperature. CW output power of 11 mW is obtained with 900 mW launched pump power at 885 nm. It must be noted that such lasers are of prime importance for military and space applications because they lie within an atmospheric window transparent from 3 /tm to 5 /tm. Very few lasers exist in this spectral region. [Pg.266]

In the D-region, under typical conditions, most of the ionization is due to the effect of the solar Lyman a ray on nitric oxide (Nicolet, 1945). The ionization potential of the NO molecule is only 9.25 eV, which corresponds to a wavelength of 134 nm. In the spectral region of the Lyman a line an atmospheric window exists due to the low absorption cross section of O2 in this interval, and thus the ionizing radiation can... [Pg.542]

Fig. 2-5. The solar flux spectrum in the 120-800 nm wavelength region (a) outside the earth atmosphere, (b) at sea level, and (c) at about 30 km altitude to show the atmospheric window in the 185-215 nm wavelength region. Fig. 2-5. The solar flux spectrum in the 120-800 nm wavelength region (a) outside the earth atmosphere, (b) at sea level, and (c) at about 30 km altitude to show the atmospheric window in the 185-215 nm wavelength region.
All halocarbons are active absorbers of infrared radiation. Of special interest are absorption features in the infrared atmospheric window (7-9 p,m wavelength) region, because here even relatively small increments in atmospheric abundances will have a pronounced impact on the atmospheric radiation balance, leading to a global temperature increase in the same way as that projected to result from the rise in the mixing ratio of C02 (see Section 11.1). This effect is expected to accompany the reduction of stratospheric ozone and calls for more effective emission controls of anthropogenic halocarbons. [Pg.276]

Currently there is a lack of observational capability in the Far Infrared. ALMA (Wootten and Thompson 2009) will explore a number of wide atmospheric windows at millimeter wavelengths, and at longer wavelengths in the radio region astronomers... [Pg.6]

Table 1 lists some of the gases that can be observed in the window regions of the atmosphere. It shows that a large number of target gases can be detected by remote gas-sensing systems that are capable of operation at the correct wavelengths. [Pg.4238]

OPTICAL DETECTORS sense and measure electromagnetic radiation in the broad spectral region from the longest infrared wavelength atmospheric window at A, = 10 /u.m to the ultraviolet end of the visible spectrum at A. = 0.3 /u.m. The detection process may depend upon the heat generated by the incident radiation (thermal detection) or by the photoexcitation of electrons or... [Pg.212]


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Atmosphere, regions

Atmospheres windows

Atmospheric windows

Regional atmosphere

Window regions

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