by O. S. Kirsebom, M. Alcorta, M. J. G. Borge, M. Cubero, C. Aa. Diget, L. M. Fraile, B. R. Fulton, H. O. U. Fynbo, D. Galaviz, B. Jonson, M. Madurga, T. Nilsson, G. Nyman, K. Riisager, O. Tengblad and M. Turrión
Abstract:
The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0+ state in 12C, commonly known as the Hoyle state, proceeds sequentially via the ground state of 8Be. This assumption is challenged by the recent identification of two direct α-decay branches with a combined branching ratio of 17(5)%. If correct, this would imply a corresponding reduction in the triple-α reaction rate with important astrophysical consequences. We have used the 11B(3He,d) reaction to populate the Hoyle state and measured the decay to three α particles in complete kinematics. We find no evidence for direct α-decay branches, and hence our data do not support a revision of the triple-α reaction rate. We obtain an upper limit of 5×10−3 on the direct α decay of the Hoyle state at 95% C.L., which is 1 order of magnitude better than a previous upper limit.
Reference:
O. S. Kirsebom, M. Alcorta, M. J. G. Borge, M. Cubero, C. Aa. Diget, L. M. Fraile, B. R. Fulton, H. O. U. Fynbo, D. Galaviz, B. Jonson, M. Madurga, T. Nilsson, G. Nyman, K. Riisager, O. Tengblad and M. Turrión, “Improved Limit on Direct alpha Decay of the Hoyle State”, Physical Review Letters, vol. 108, no. 20, pp. 202501.
Bibtex Entry:
@article{kirsebom_improved_2012,
title = {Improved {Limit} on {Direct} alpha {Decay} of the {Hoyle} {State}},
volume = {108},
url = {https://link.aps.org/doi/10.1103/PhysRevLett.108.202501},
doi = {10.1103/PhysRevLett.108.202501},
abstract = {The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0+ state in 12C, commonly known as the Hoyle state, proceeds sequentially via the ground state of 8Be. This assumption is challenged by the recent identification of two direct α-decay branches with a combined branching ratio of 17(5)%. If correct, this would imply a corresponding reduction in the triple-α reaction rate with important astrophysical consequences. We have used the 11B(3He,d) reaction to populate the Hoyle state and measured the decay to three α particles in complete kinematics. We find no evidence for direct α-decay branches, and hence our data do not support a revision of the triple-α reaction rate. We obtain an upper limit of 5×10−3 on the direct α decay of the Hoyle state at 95% C.L., which is 1 order of magnitude better than a previous upper limit.},
number = {20},
urldate = {2020-07-10},
journal = {Physical Review Letters},
author = {Kirsebom, O. S. and Alcorta, M. and Borge, M. J. G. and Cubero, M. and Diget, C. Aa. and Fraile, L. M. and Fulton, B. R. and Fynbo, H. O. U. and Galaviz, D. and Jonson, B. and Madurga, M. and Nilsson, T. and Nyman, G. and Riisager, K. and Tengblad, O. and Turrión, M.},
month = may,
year = {2012},
pages = {202501},
file = {APS Snapshot:E:\Usuarios\Administrator\Zotero\storage\HVKHHXYZ\PhysRevLett.108.html:text/html;Full Text PDF:E:\Usuarios\Administrator\Zotero\storage\T4972SE8\Kirsebom et al. - 2012 - Improved Limit on Direct $ensuremath alpha $ Dec.pdf:application/pdf},
}