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Available isotopes for Rhenium (Z=75)
Recommended MACS30 (Maxwellian Averaged Cross Section @ 30keV)
185Re 186Re
Cross sections do not include stellar enhancement factors! History
(Version 0.0 corresponds to Bao et al.) Comment
Note that the existing activation data determined only the partial cross section to the short-lived ground-state, not including the long-lived isomeric state. Time-of-flight measurements include both components but the existing data is 40 years old. The new rec. value to the isomer was calculated according to HSK05 with the ratio between the partial cross section to the isomer and the ground-state, R(m/g)= 0.54 (11) % at thermal energies, and extrapolated to R(m/g)= 1.3 (8) % at kT= 30 keV.
The new rec. partial cross section to ground-state was recalculated using new decay data NDS186 (neglecting the 1.5% change in the half-life), and extrapolating this recalculated data with the normalized energy dependencies of the evaluated libraries (endfb71, jeff30A, jeff312). This assumes the same energy dependence for the total and the partial cross section. The new uncertainty is the standard deviation between the normalized libraries (0.5-2.3%) plus the recalculated uncertainty of the single measurements in KJB91 (2.1-3.1%). Last review: February 2014 List of all available values
Original:MACS [<σ v>/vT] (mb) for kT=30 keV, based on the published cross sections except where indicated otherwise. Renorm:MACS [<σ v>/vT] (mb) for kT=30 keV for which the reference or standard cross section was meanwhile improved. Type: The letters and numbers in the column labelled 'type' give information on how the cross section has been obtained:
MACS, SEF and Reaction Rates for different energies
MACS: Reference: KJB91,HSK05,endfb71,jeff30A,jeff312 Procedure: 'e+t' (The MACS from kT=5 keV to 100 keV are derived from calculated cross sections, which are then normalized to experimental data, e.g. to the values at kT=25 keV obtained in activation measurements. In these cases the uncertainties should be linearly increased below 25 and above 30 keV to reach about 30% at the extreme kT values.) Year: 2013 X-factor: Reference: Year: SEF (Stellar enhancement factor): Reference: Year: Comment: Rate: Reaction rate NA<σv> given in 108 cm3/mole/s, including SEF Chart of nuclei
Isotope: Rhenium
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