Experimental study of time and frequency properties of collective nuclear excitations in a single crystal (gamma-ray resonance)

摘要: The angular dependences of the time and frequency parameters a single-crystal collective nuclear resonance were studied in unified series measurements compared with an isolated nucleus. It was shown that, when approaching Bragg angle ( theta B), coherent character gamma radiation interaction system crystal causes drastic changes parameters. A sharp reduction response time-from 230+or-10 ns for nucleus to 40+or-10 at peak-takes place. width increases from 3.5 Gamma 0 is natural width) 20+or-0.5 0. energy non-monotonically incidence on deviates by (2.0+or-0.5) as maximum. excitation spectra resonances have asymmetrical shape. sign asymmetry crossing position. properties excitations analysed theory Kagan, Afanas'ev Perstnev, well that Kohn.