Search for X-ray induced decay of the 31-yr isomer of 178Hf using synchrotron radiation

Technical Report · Mon Sep 13 00:00:00 EDT 2004

DOI:https://doi.org/10.2172/15011624· OSTI ID:15011624

Ahmad, I; Banar, J C; Becker, J A; Bredeweg, T A; Cooper, J R; Gemmell, D S; Kraemer, A; Mashayekhi, A; McNabb, D P; Miller, G G; Moore, E F; Palmer, P; Pangault, L N; Rundberg, R S; Schiffer, J P; Shastri, S D; Wang, T F; Wilhelmy, J B

Isomeric {sup 178}Hf (t{sub 1/2} = 31 yr, E{sub x} = 2.446 MeV, J{sup {pi}} = 16{sup +}) was bombarded by a white beam of x-rays from the Advanced Photon Source at Argonne National Laboratory. A search was made for x-ray induced decay of the isomer by detecting prompt and delayed {gamma} rays associated with the decay. No induced decay was observed. Upper limits for such a process for x-ray energies between 7-100 keV were set. The limits between 7 and 30 keV are below {approx} 3 x 10{sup -27} cm{sup 2}-keV for induced decay that bypasses the 4-s isomer and {approx} 5 x 10{sup -27} cm{sup 2}-keV for induced decay that is delayed through this isomer, orders of magnitude below values at which induced decay was reported previously. These limits are consistent with what is known about the properties of atomic nuclei.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 15011624
• Report Number(s): UCRL-TR-206598; TRN: US0501342
• Resource Relation: Other Information: PBD: 13 Sep 2004
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ADVANCED PHOTON SOURCE
DECAY
ISOMERS
NUCLEI
SYNCHROTRON RADIATION