Radiative decay branching ratio of the Hoyle state

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Luo, Zifeng, Barbui, M., Bishop, J., Chubarian, G., Goldberg, V. Z., Harris, E., Koshchiy, E., Parker, C. E., Roosa, M., Saastamoinen, A., Scriven, D. P., Rogachev, G. V.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913234221531136
author Luo, Zifeng
Barbui, M.
Bishop, J.
Chubarian, G.
Goldberg, V. Z.
Harris, E.
Koshchiy, E.
Parker, C. E.
Roosa, M.
Saastamoinen, A.
Scriven, D. P.
Rogachev, G. V.
author_facet Luo, Zifeng
Barbui, M.
Bishop, J.
Chubarian, G.
Goldberg, V. Z.
Harris, E.
Koshchiy, E.
Parker, C. E.
Roosa, M.
Saastamoinen, A.
Scriven, D. P.
Rogachev, G. V.
contents Background: The triple-alpha process is a vital reaction in nuclear astrophysics, characterized by two consecutive reactions [$2α\leftrightarrows{^{8}\rm{Be}}(α,γ){^{12}\rm{C}}$] that drive carbon formation. The second reaction occurs through the Hoyle state, a 7.65 MeV excited state in ${^{12}\rm{C}}$ with $J^π=0^{+}$. The rate of the process depends on the radiative width, which can be determined by measuring the branching ratio for electromagnetic decay. Recent measurements by Kibédi et al. conflicted with the adopted value and resulted in a significant increase of nearly 50\% in this branching ratio, directly affecting the triple-alpha reaction. Purpose: This work aims to utilize charged-particle spectroscopy with magnetic selection as a means to accurately measure the total radiative branching ratio ($Γ_{\rm{rad}}/Γ$) of the Hoyle state in $^{12}{\rm C}$. Methods: The Hoyle state in $^{12}{\rm C}$ was populated via $^{12}\rm{C}(α, α')^{12}\rm{C^{*}}$ inelastic scattering. The scattered $α$ particles were detected using a $Δ$E-E telescope, while the recoiled $^{12}{\rm C}$ ions were identified in a magnetic spectrometer. Results: A radiative branching ratio value of $Γ_{\rm{rad}}/Γ\times10^{4}=4.0\pm0.3({\rm stat.})\pm0.16({\rm syst.})$ was obtained. Conclusions: The radiative branching ratio for the Hoyle state obtained in this work is in agreement with the original adopted value. Our result suggests that the proton-$γ$-$γ$ spectroscopy result reported by Kibédi et al. may be excluded.
format Preprint
id arxiv_https___arxiv_org_abs_2310_18475
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Radiative decay branching ratio of the Hoyle state
Luo, Zifeng
Barbui, M.
Bishop, J.
Chubarian, G.
Goldberg, V. Z.
Harris, E.
Koshchiy, E.
Parker, C. E.
Roosa, M.
Saastamoinen, A.
Scriven, D. P.
Rogachev, G. V.
Nuclear Experiment
Solar and Stellar Astrophysics
Background: The triple-alpha process is a vital reaction in nuclear astrophysics, characterized by two consecutive reactions [$2α\leftrightarrows{^{8}\rm{Be}}(α,γ){^{12}\rm{C}}$] that drive carbon formation. The second reaction occurs through the Hoyle state, a 7.65 MeV excited state in ${^{12}\rm{C}}$ with $J^π=0^{+}$. The rate of the process depends on the radiative width, which can be determined by measuring the branching ratio for electromagnetic decay. Recent measurements by Kibédi et al. conflicted with the adopted value and resulted in a significant increase of nearly 50\% in this branching ratio, directly affecting the triple-alpha reaction. Purpose: This work aims to utilize charged-particle spectroscopy with magnetic selection as a means to accurately measure the total radiative branching ratio ($Γ_{\rm{rad}}/Γ$) of the Hoyle state in $^{12}{\rm C}$. Methods: The Hoyle state in $^{12}{\rm C}$ was populated via $^{12}\rm{C}(α, α')^{12}\rm{C^{*}}$ inelastic scattering. The scattered $α$ particles were detected using a $Δ$E-E telescope, while the recoiled $^{12}{\rm C}$ ions were identified in a magnetic spectrometer. Results: A radiative branching ratio value of $Γ_{\rm{rad}}/Γ\times10^{4}=4.0\pm0.3({\rm stat.})\pm0.16({\rm syst.})$ was obtained. Conclusions: The radiative branching ratio for the Hoyle state obtained in this work is in agreement with the original adopted value. Our result suggests that the proton-$γ$-$γ$ spectroscopy result reported by Kibédi et al. may be excluded.
title Radiative decay branching ratio of the Hoyle state
topic Nuclear Experiment
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2310.18475