Accession Number : AD0289844

Title :   RESONANCE ABSORPTION OF GAMMA-RAYS IN NORMAL AND SUPERCONDUCTING TIN

Corporate Author : WASHINGTON UNIV ST LOUIS MO

Personal Author(s) : YAQUB,M. ; HOHENEMSER,C.

Report Date : DEC 1962

Pagination or Media Count : 1

Abstract : A study of the resonant absorption of the 23.8 KeV gamma-rays in Sn-119 was made between 373 and 1.1 K by using the Sb-119 K-capture parent. The source was prepared by bombarding natural Sn with 10 MeV deuterons in a cyclotron, and was thick enough to absorb resonantly a large portion of the recoilless photons emitted. By studying the self-absorption in this source between 373 and 60 K and taking into account the contributions to the intensity due to resonant scattering, an average value of the Debye temperature, theta, was derived. In order to see if the phonon spectrum undergoes a change in passing from the superconducting to the normal phase, the counting rate was measured at several temperatures between 4.2 and 1.1 K, with and without a magnetic field strong enough to destroy the superconductivity of the source. Using the derived value of 140 K for theta, it was concluded that the change in theta between the two phases could not be more than 0.76 K. (Author)

Descriptors :   *RESONANCE ABSORPTION, *SUPERCONDUCTORS, *TIN, DEUTERON BOMBARDMENT, GAMMA RAYS, ISOTOPES, PHONONS, PHOTONS

Distribution Statement : APPROVED FOR PUBLIC RELEASE