Chang Ho Hyun Daegu University Korea Baryons 2013, Glasgow June 25, 2013 Hadronic weak interactions from the photodisintegration of the deuteron

Outline  Aim  Theory  Results  Prospects

Aim  Strong interactions: Modern potentials (Av18, CD Bonn, Nijimegen 97, …), Effective field theories (EFTs)  Electromagnetic interactions: EM transitions  Gravitation: General relativity, neutron stars  Weak interactions: ? Nucleon-nucleon interactions below pion threshold

DDH potential: Parity-violating (PV) one-meson exchange Weak interactions at hadronic scale

Issues with DDH potential Correct form? Missing term? Values of the coupling constants? Effective field theory for parity-violating NN interactions Systematic expansion Pionful theory Pionless theory Aim Establish a consistent description of PV NN interaction with a pionless EFT

Theory Low-energy EFT  LECs  PV LECs

PV interactions in the pionless EFT with dibaryons Five PV LECs  nn, pp: h 0s1,2 dNN  np: h 0s3 dNN, h 0t dNN, h 1 dNN

Observables: Polarization P i’ in d  → pol(n)p (i=x, y, z) p n  z’ y’  i (  ) : differential cross section with neutron spin parallel and anti-parallel along the axis i

Feynman diagrams

Results Transition amplitude Parity-conservingParity-violating

P z’ A  (exp) = -(0.15±0.48)  How large: Compare to the asymmetry in pol(n)p → d  at threshold

P x’ How large: Compare to the polarization in np → d  at threshold P  (exp) = (1.8±1.8)  10 -7

Prospects Large P z’, non-negligible P x’ A  in pol(n)p → d  : NPDGamma collaboration at SNS P  in pol(  )d → np: TUNL HIGS upgrade, Shanghai P i’ in d  → pol(n)p: Useful for counter-determination of PV LECs

Thank you.

PV observables and data in the few-nucleon systems Process (MeV)Observable Exp. (  10 7 ) pp scat. (13.6)Longitudinal asymmetry-0.93±0.21 pp scat. (45)Longitudinal asymmetry-1.57±0.23 p  scat. (46) Longitudinal asymmetry-3.34±0.93 np capturePolarization1.8±1.8 pol(n)p captureAsymmetry-(0.15±0.48) pol(n)d captureAsymmetry42±38

PV coupling constants can be determined from data, e.g. aa aa aa Paris Av Asymmetry in pol(n)p capture Polarization in np capture p  p  p0p0 Bonn Av