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Available isotopes for Gold (Z=79)
197Au 198Au
Recommended MACS30 (Maxwellian Averaged Cross Section @ 30keV)
197Au 198Au
Cross sections do not include stellar enhancement factors! History
(Version 0.0 corresponds to Bao et al.) Comment
RR: will provide new text here.
Au-197 is used as standard for most astrophysical cross section measurements. Unfortunately, it is at the moment only a standard in the thermal region and between E(n)= 200 keV and 2.8 MeV (au197). Recent measurements at nTOF (CL11, CM10) and GELINA (MBD14) show a discrepancy of about 5% to the previously used standard value at kT= 30 keV from RaK88 and Mac82e. The new recommended standard cross section for the astrophysical energy region was derived between kT= 5 and 50 keV by the weighted average of the GELINA measurement of MBD14 and the nTOF measurement of CL11,CM10. The uncertainty in this energy range was taken from MBD14. For the energies between kT= 60-100 keV we used the average of the recent libraries (jeff32, jendl40, endfb71) and the uncertainty from the standard deviation given in jeff32 and endfb71. The previous standard value used for activations with the Li-7(p,n)Be-7 reaction at E(p)= 1912 keV was 586 (9) mb, the so-called "Ratynski value" (RaK88). At this energy the neutrons are collimated in a forward cone of 120 degree opening angle and resemble a quasi-stellar neutron spectrum of kT= 25 keV. With the new results this value would change to 632 (9) mb. Last review: In process 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: Rei18 Procedure: 'd' (Renormalized 2017 based on updated Au measurement) Year: 2018 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: Gold
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