| Autor: |
Gewurtz, S., Gornall, W. S., Stoicheff, B. P. |
| Zdroj: |
Journal of the Acoustical Society of America; 1971, Vol. 49 Issue 3C, p994-1000, 7p |
| Abstrakt: |
Brillouin spectra of ethyl ether and carbon disulfide (at 20.0°C) were investigated for scattering angles of 20°-145°. A single-mode laser was used for excitation; scattered light was collected in a solid angle of 1.5×10-4 sr; and the total instrumental width was ∼100 Mc/sec. Linewidths of 10±5 to 215±10 Mc/sec were measured and velocities determined to an accuracy of ±0.5%. In ethyl ether the phonon velocity and attenuation were constant in the frequency range 0.8-4.1 Gc/sec, and the values agreed with acoustic measurements at 100 Mc/sec. In CS2 a considerable decrease in attenuation was observed in the range 1.7-6.1 Gc/sec, with the value at high frequency approaching the classical attenuation attributed to shear viscosity. This variation in attenuation is in good agreement with the theory of a single relaxation time for the total vibrational specific heat, as established by acoustic measurements in the frequency range 2-200 Mc/sec. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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