Authors:	Acharya, Bijaya Bacca, Sonia
Title:	Gaussian process error modeling for chiral effective-field-theory calculations of np ↔ dγ at low energies
Online publication date:	17-Apr-2023
Year of first publication:	2022
Language:	english
Abstract:	We calculate the energy-dependent cross section of the np ↔ dγ process in chiral effective field theory and apply state-of-the-art tools for quantification of theory uncertainty. We focus on the low-energy regime, where the magnetic dipole and the electric dipole transitions cross over, including the range relevant for big-bang nucleosynthesis. Working with the leading one- and two-body electromagnetic currents, we study the order-by-order convergence of this observable in the chiral expansion of the nuclear potential. We find that the Gaussian process error model describes the observed convergence very well, allowing us to present Bayesian credible intervals for the truncation error with correlations between the cross sections at different energies taken into account. We obtain a 1σ estimate of about 0.2% for the uncertainty from the truncation of the nuclear potential. This is an important step towards calculations with statistically interpretable uncertainties for astrophysical reactions involving light nuclei.
DDC:	530 Physik 530 Physics
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 08 Physik, Mathematik u. Informatik Helmholtz Institut Mainz
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8914
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Physics letters : B 827
Pages or article number:	137011
Publisher:	Elsevier
Publisher place:	Amsterdam
Issue date:	2022
ISSN:	1873-2445
Publisher DOI:	10.1016/j.physletb.2022.137011
Appears in collections:	DFG-491381577-D