Photon Asymmetries in $${nd\rightarrow}$$ n d → 3 Hγ Using EFT( $${/\!\!\!\pi}$$ / π ) Approach

Abstract

The parity-violating Lagrangian of the weak nucleon-nucleon (N N ) interaction in the pionless effective field theory (EFT(/ π)) approach contains five independent unknown low-energy coupling constants (LECs). The photon asymmetry with respect to neutron polarization in np → dγ A Then, we evaluate photon asymmetry with respect to the neutron polarization a nd γ and the photon asymmetry in relation to deuteron polarization A nd γ in nd → 3 Hγ process. We finally compare our EFT(/ π) photon asymmetries results with the experimental values and the previous calculations based on the DDH model.PACS numbers:

Parity-violating photon circular polarization in p+d→He3+γ with pion-less effective field theory

“…In the present circumstance with no available experimental data Moeini Arani and Bayegan have introduced the PV dl , and P nd γ to the DDH "best values" estimates for these observables [26]. Vanasse has also obtained a different values for five PV LECs g (x−y) [27].…”

“…The determined values of the PV coupling constants g (x−y) . The PV coupling constants values in the second and third rows are the estimations based on the evaluation by Moeini Arani [26] and the extraction from Vanasse [27], respectively. All values are in units of MeV − 3 2 .…”

“…The difference between the values of P pd γ according to two different values of the PV coupling constants in Refs. [26,27] can be assessed by the future experimental data.…”

“…The results for the photon circular polarization of the p d → 3 He γ at LO are shown at the energy 0.5 E Lab 3 MeV with = 600. The results in the second and third columns are obtained based on the set of the g (x−y) estimated in Refs [26]. and[27], respectively.…”