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s-process branching at 185W revised

P. Mohr·T. Shizuma·H. Ueda·S. Goko·A. Makinaga·K. Y. Hara·T. Hayakawa·Y. -W. Lui·H. Ohgaki·H. Utsunomiya
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Abstract

The neutron capture cross section of the unstable s-process branching nucleus 185W has been derived from experimental data of the inverse 186W(g,n)185W photodisintegration taken with monochromatic photon beams from laser Compton scattering. The result of sigma = 553 +- 60 mb at kT = 30 keV leads to a relatively high effective neutron density in the classical s-process of N_n = 4.7 \times 10^8 cm^-3. A realistic model for the s-process in thermally pulsing AGB stars overestimates the abundance of 186Os significantly because of the relatively small neutron capture cross section of 185W.

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P. Mohr, T. Shizuma, H. Ueda, S. Goko, A. Makinaga, K. Y. Hara, T. Hayakawa, Y. -W. Lui, H. Ohgaki, H. Utsunomiya. 2004-09-27. s-process branching at 185W revised. https://doi.org/10.1103/physrevc.69.032801

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