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Title: Investigation of the 7 Li(p,n) neutron fields at high energies
The neutron activation method is well-suited to investigate neutron-capture cross sections relevant for the main s-process component. Neutrons can be produced via the 7 Li(p,n) reaction with proton energies of 1912 keV at e.g. Van de Graaff accelerators, which results in a quasi-Maxwellian spectrum of neutrons corresponding to a temperature of k B T = 25 keV. However, the weak s-process takes place in massive stars at temperatures between 25 and 90 keV. Simulations using the PINO code [2] suggest that a Maxwellian spectrum for higher energies, e.g. k B T = 90 keV, can be approximated by a linear combination of different neutron spectra. To validate the PINO code at proton energies E p ≠ 1912 keV, neutron time-of-flight measurements were carried out at the PTB Ion Accelerator Facility (PIAF) at the Physikalisch-Technische Bundesanstalt in Braunschweig, Germany.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Liu, W.; Wang, Y.; Guo, B.; Tang, X.; Zeng, S.
Date Published:
Journal Name:
EPJ Web of Conferences
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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