Rigorous constraints on three-nucleon forces in chiral effective field theory from fast and accurate calculations of few-body observables

Understand

We explore the constraints on the three-nucleon force (3NF) of chiral effective field theory ($\chi$EFT) 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 uncertainty due to truncation of the $\chi$EFT expansion at next-to-next-to-leading order.
• A consistent solution for the ${}^3$H binding energy, the ${}^4$He binding energy and radius, and the ${}^3$H $\beta$-decay rate can only be obtained if $\chi$EFT truncation errors are included in the analysis.
• All of these except the $\beta$-decay rate give essentially degenerate constraints on the 3NF low-energy constants, so it is crucial for estimating these parameters.