Title: Ab Initio Prediction of the ⁴$$\mathrm{H}$$e($d, γ$)⁶$$\mathrm{L}$$i Big Bang Radiative Capture

Abstract

We report the rate at which helium (⁴He ) and deuterium (d) fuse together to produce lithium-6 (⁶Li) and a γ ray, ⁴$$\mathrm{H}$$e($d, γ$)⁶$$\mathrm{L}$$i, is a critical puzzle piece in resolving the discrepancy between big bang predictions and astronomical observations for the primordial abundance of ⁶Li . The accurate determination of this radiative capture rate requires the quantitative and predictive description of the fusion probability across the big bang energy window (30 keV ≲ E ≲ 400 keV), where measurements are hindered by low counting rates. We present first-principle (or, ab initio) predictions of the ⁴$$\mathrm{H}$$e($d, γ$)⁶$$\mathrm{L}$$i astrophysical S factor using validated nucleon-nucleon and three-nucleon interactions derived within the framework of chiral effective field theory. By employing the ab initio no-core shell model with continuum to describe ⁴He-d scattering dynamics and bound ⁶Li product on an equal footing, we accurately and consistently determine the contributions of the main electromagnetic transitions driving the radiative capture process. Our results reveal an enhancement of the capture probability below 100 keV owing to previously neglected magnetic dipole (M1) transitions and reduce by an average factor of 7 the uncertainty of the thermonuclear capture rate between 0.002 and 2 GK.

Authors:

Hebborn, C.  ^[1];

• Search DOE PAGES for author "Hebborn, C."
• Search DOE PAGES for ORCID "0000-0002-0084-2561"

Hupin, G.  ^[2];

• Search DOE PAGES for author "Hupin, G."
• Search DOE PAGES for ORCID "0000-0002-4285-7411"

Kravvaris, K.  ^[3];

• Search DOE PAGES for author "Kravvaris, K."
• Search DOE PAGES for ORCID "0000-0002-1715-0967"

Quaglioni, S.  ^[3];

• Search DOE PAGES for author "Quaglioni, S."
• Search DOE PAGES for ORCID "0000-0002-7512-605X"

Navrátil, P.  ^[4];

• Search DOE PAGES for author "Navrátil, P."
• Search DOE PAGES for ORCID "0000-0002-6535-2141"

Gysbers, P.  ^[5]

• Search DOE PAGES for author "Gysbers, P."
• Search DOE PAGES for ORCID "0000-0002-5269-9170"

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+ Show Author Affiliations

1. Facility for Rare Isotope Beams, East Lansing, MI (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2. Université Paris-Saclay, Orsay (France)
3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
4. TRIUMF, Vancouver, BC (Canada); University of British Columbia, Vancouver, BC (Canada)
5. TRIUMF, Vancouver, BC (Canada); Univ. of British Columbia, Vancouver, BC (Canada)

Publication Date:

Wed Jul 20 00:00:00 EDT 2022

Research Org.:

Michigan State Univ., East Lansing, MI (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Nuclear Physics (NP); USDOE Laboratory Directed Research and Development (LDRD) Program; National Research Council of Canada

OSTI Identifier:

1923671

Alternate Identifier(s):

OSTI ID: 1887494

Report Number(s):

LLNL-JRNL-832850
Journal ID: ISSN 0031-9007; SAPIN-2016-0003; SAPPJ-2019-00039; PGSD3-535536-2019; TRN: US2312452

Grant/Contract Number:  

SC0013617; AC52-07NA27344; SAPIN-2016-00033; SAPPJ-2019-00039; PGSD3-535536-2019

Resource Type:

Accepted Manuscript

Journal Name:

Physical Review Letters

Additional Journal Information:

Journal Volume: 129; Journal Issue: 4; Journal ID: ISSN 0031-9007

Publisher:

American Physical Society (APS)

Country of Publication:

United States

Language:

English

Subject:

73 NUCLEAR PHYSICS AND RADIATION PHYSICS; big bang nucleosynthesis; cluster models; nuclear many-body theory; nuclear reactions; radiative capture