Speaker
Prof.
Daniel Phillips
(Ohio University)
Description
We explore the constraints on the three-nucleon force (3NF) of chiral effective field theory (χEFT) that are provided by bound-state observables in the A = 3 and A = 4 sectors. Our statistically rigorous analysis incorporates experimental error, computational method uncertainty, and the un- certainty due to truncation of the χEFT expansion at next-to-next-to-leading order. A consistent solution for the 3H binding energy, the 4He binding energy and radius, and the 3H β-decay rate can only be obtained if χEFT truncation errors are included in the analysis. All of these except the β-decay rate give essentially degenerate constraints on the 3NF low-energy constants, so it is crucial for estimating these parameters. We use eigenvector continuation for fast and accurate emulation of No-Core Shell Model calculations of the considered few-nucleon observables. This facilitates sam- pling of the posterior probability distribution, allowing us to also determine the distributions of the hyperparameters that quantify the truncation error. We find a χEFT expansion parameter of Q = 0.33 ± 0.06 for these observables.
Primary author
Prof.
Daniel Phillips
(Ohio University)
Co-authors
Prof.
Andreas Ekström
(Chalmers University of Technology)
Prof.
Christian Forssén
(Chalmers University of Technology)
Prof.
Isak Svensson
(Chalmers University of Technology)
Dr
Jordan Melendez
(The Ohio State University)
Prof.
Richard Furnstahl
(The Ohio State University)
Prof.
Sarah Wesolowski
(Salisbury University)
