1996 Fiscal Year Final Research Report Summary
Study of CO_2 laser pumped infrared emission spectroscopy
| Project/Area Number |
07640692
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Physical chemistry
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| Research Institution | National Astronomical Observatory |
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Principal Investigator |
KAWAGUCHI Kentarou Department of Radio Astronomy National Astronomical Observatory Associate Prof., 電波天文学研究系, 助教授 (40158861)
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| Project Period (FY) |
1995 – 1996
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| Keywords | Emission Spectroscopy / High-resolution FTIR / Energy transfer |
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| Research Abstract |
Sensitivity of emission spectroscopy is generally higher than that of absorption spectroscopy. However, in infrared region the emission method has disadvantage because of longer wavelength compared with the cases in visible and ultraviolet regions, and its application is limited mainly diatomic molecules. On the other hand, a high-power CO_2 laser is known to be a good pumping source for generating far-infrared laser oscillation, where molecules pumped by CO_2 laser must have suitable vibrational frequencies in the 10 mum region. Therefore, all molecules do not necessarily give infrared or far-infrared emission.
In the present study, the SF_6 molecule has been used as sensitizer for observing emission from molecules, where SF_6 absorbs CO_2 laser energy, and the hot SF_6 molecules transfer the absorbed energy to other molecules. The emission was observed by a high-resolution Fourier transform spectrometer. All molecules with non-zero vibrational transition moments like as CO,N_2O,C_2H_2, CH_4, di-tert butyl peroxide etc. showed strong emission. Among these molecules, N_2O emission spectra were analyzed in detail, and rotational excitation temperature of 819 (9) K was determined from the relative intensities of vibration-rotation lines. The total energy of vibration, rotation and translation motions of N_2O reached up to more than 7000 cm^<-1>, which indicates that at least 8 photon energy of the CO_2 laser is transfered to the N_2O molecule. It is found that the present method is useful for study of energy transfer process.
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Research Products
(4 results)
