Nuclear internal conversion between bound atomic states

Journal Article · Fri Jan 24 04:00:00 EST 2003 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.1536380· OSTI ID:20636456

Chemin, J F; Harston, M R; Carreyre, J; Aleonard, M M; Scheurer, J N ^[1]; Karpeshin, F F ^[1]; Attallah, F ^[2]; Boggaert, G ^[3]; Grandin, J R ^[4]; Trzhaskovskaya, M B ^[5]

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1. CENBG, BP 120, F33175, Gradignan Cedex (France)
2. GSI, D-6100 Darmstad (Germany)
3. LPNHE, Ecole Polytechnique, 91128 Palaiseau (France)
4. CIRIL, BP 5133, F-14040 Caen (France)
5. Saint Petersbourg, Nuclear Physics Institute, Gatchira, Saint-Petersbourg (Russian Federation)

We present experimental and theoretical results for rate of decay of the (3/2)+ isomeric state in 125Te versus the ionic charge state. For charge state larger than 44 the nuclear transition lies below the threshold for emission of a K-shell electron into the continuum with the result that normal internal conversion is energetically forbidden. Rather surprisingly, for the charge 45 and 46 the lifetime of the level was found to have a value close to that in neutral atoms. We present direct evidence that the nuclear transition could still be converted but without the emission of the electron into the continuum, the electron being promoted from the K-shell to an other empty bound state lying close to the continuum. We called this process BIC. The experimental results agree with theoretical calculations if BIC resonances are taken into account. This leads to a nuclear decay constant that is extremely sensitive to the precise initial state and simple specification of the charge state is no longer appropriate. The contribution to decay of the nucleus of BIC has recently been extended to the situation in which the electron is promoted to an intermediate filled bound state (PFBIC) with an apparent violation of the Pauli principle. Numerical results of the expected dependence of PFBIC on the charge state will be presented for the decay of the 77.351 keV level in 197Au.

• OSTI ID: 20636456
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 652; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATOMS
BOUND STATE
CHARGE STATES
ELECTRON EMISSION
ELECTRONS
ENERGY LEVELS
GOLD 197
INNER-SHELL IONIZATION
INTERNAL CONVERSION
K SHELL
KEV RANGE
LIFETIME
NUMERICAL ANALYSIS
PAULI PRINCIPLE
RESONANCE
TELLURIUM
TELLURIUM 125