Improved limit on direct α decay of the Hoyle state

O.S. Kirsebom; H.O.U. Fynbo; K. Riisager; M. Alcorta; M.J.G. Borge; M. Cubero; D. Galaviz; M. Madurga; O. Tengblad; M. Turrión; C.A. Diget; B.R. Fulton; L.M. Fraile; B. Jonson; T. Nilsson; G. Nyman

doi:10.1103/PhysRevLett.108.202501

Improved limit on direct α decay of the Hoyle state

O.S. Kirsebom, H.O.U. Fynbo, K. Riisager, M. Alcorta, M.J.G. Borge, M. Cubero, D. Galaviz, M. Madurga, O. Tengblad, M. Turrión, C.A. Diget, B.R. Fulton, L.M. Fraile, B. Jonson, T. Nilsson, G. Nyman

Research output: Contribution to journal › Article › peer-review

Abstract

The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0 state in C12, commonly known as the Hoyle state, proceeds sequentially via the ground state of Be8. 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 B11(He3,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. © 2012 American Physical Society.

Original language	English
Article number	202501
Pages (from-to)	1-4
Number of pages	4
Journal	Physical Review Letters
Volume	108
Issue number	20
DOIs	https://doi.org/10.1103/PhysRevLett.108.202501
Publication status	Published - 14 May 2012

Access to Document

10.1103/PhysRevLett.108.202501

Cite this

Kirsebom, O. S., Fynbo, H. O. U., Riisager, K., Alcorta, M., Borge, M. J. G., Cubero, M., Galaviz, D., Madurga, M., Tengblad, O., Turrión, M., Diget, C. A., Fulton, B. R., Fraile, L. M., Jonson, B., Nilsson, T., & Nyman, G. (2012). Improved limit on direct α decay of the Hoyle state. Physical Review Letters, 108(20), 1-4. Article 202501. https://doi.org/10.1103/PhysRevLett.108.202501

@article{91ac4073a7cb42ea922e44727b6049b4,

title = "Improved limit on direct α decay of the Hoyle state",

abstract = "The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0 state in C12, commonly known as the Hoyle state, proceeds sequentially via the ground state of Be8. 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 B11(He3,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. {\textcopyright} 2012 American Physical Society.",

author = "O.S. Kirsebom and H.O.U. Fynbo and K. Riisager and M. Alcorta and M.J.G. Borge and M. Cubero and D. Galaviz and M. Madurga and O. Tengblad and M. Turri{\'o}n and C.A. Diget and B.R. Fulton and L.M. Fraile and B. Jonson and T. Nilsson and G. Nyman",

year = "2012",

month = may,

day = "14",

doi = "10.1103/PhysRevLett.108.202501",

language = "English",

volume = "108",

pages = "1--4",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "20",

}

TY - JOUR

T1 - Improved limit on direct α decay of the Hoyle state

AU - Kirsebom, O.S.

AU - Fynbo, H.O.U.

AU - Riisager, K.

AU - Alcorta, M.

AU - Borge, M.J.G.

AU - Cubero, M.

AU - Galaviz, D.

AU - Madurga, M.

AU - Tengblad, O.

AU - Turrión, M.

AU - Diget, C.A.

AU - Fulton, B.R.

AU - Fraile, L.M.

AU - Jonson, B.

AU - Nilsson, T.

AU - Nyman, G.

PY - 2012/5/14

Y1 - 2012/5/14

N2 - The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0 state in C12, commonly known as the Hoyle state, proceeds sequentially via the ground state of Be8. 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 B11(He3,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. © 2012 American Physical Society.

AB - The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0 state in C12, commonly known as the Hoyle state, proceeds sequentially via the ground state of Be8. 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 B11(He3,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. © 2012 American Physical Society.

UR - http://www.scopus.com/inward/record.url?scp=84861606666&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.108.202501

DO - 10.1103/PhysRevLett.108.202501

M3 - Article

SN - 0031-9007

VL - 108

SP - 1

EP - 4

JO - Physical Review Letters

JF - Physical Review Letters

IS - 20

M1 - 202501

ER -

Improved limit on direct α decay of the Hoyle state

Abstract

Access to Document

Other files and links

Cite this