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We use Bayesian statistics to infer the breakdown scale of pionless effective field theory in its standard power counting and with renormalization of observables carried out using the power-divergence subtraction scheme and cutoff regularization. We condition our inference on predictions of the total neutron-proton scattering cross section up next-to-next-to leading order. We quantify a median breakdown scale of approximately 1.4 mpi . The 68% degree of belief interval is [0.96, 1.69]mpi . This result confirms the canonical expectation that the pion mass is a relevant scale in low-energy nuclear physics.
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This content will become publicly available on September 1, 2026
Breakdown scale of pionless effective field theory in the three-nucleon sector
We make order-by-order predictions of neutron–deuteron total cross sections up to next-to-next- to-leading order in pionless effective field theory. Using Bayesian methods, we infer a posterior distribution for the breakdown scale. The result shows a mode near 100 MeV, and a combined analysis with neutron–proton scattering further sharpens the inference, placing the mode close to the pion mass scale, consistent with the expected range of pionless effective field theory.vailable
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- PAR ID:
- 10650057
- Publisher / Repository:
- Physical Review C
- Date Published:
- Journal Name:
- Physical Review C
- Volume:
- 112
- Issue:
- 3
- ISSN:
- 2469-9985
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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