p′-γ-Winkelkorrelation an Cr52(p, p′ γ) und Fe56(p, p′ γ) bei 5.8 MeV

7 Be ( p , γ ) 8 B reaction

Parity Violation in − → γ p Compton Scattering

Polarized beam −→γ p Compton scattering provides a theoretically clean way to extract the isovector parity violating pion-nucleon coupling constant h (1) πNN . This channel is more tractable experimentally than the recently proposed extraction of h (1) πNN from the Bedaque-Savage process — polarized target γ −→p compton scattering. The leading parity violating effect is calculated using Heavy B...

Asymmetry in ~ n + p → d + γ

Heavy-baryon chiral perturbation theory (HBChPT) is applied to the asymmetry A γ in n+p → d + γ at threshold, which arises due to the weak parity non-conserving interactions. Instead of appealing to Siegert's theorem, transition operators up to next-to-leading chiral order are derived and the corresponding amplitudes are evaluated with the Argonne v 18 wavefunctions. In addition to the impulse ...

Parity Violation in γ−→p Compton Scattering

A measurement of parity-violating spin-dependent γ−→p Compton scattering will provide a theoretically clean determination of the parity-violating pionnucleon coupling constant h (1) πNN . We calculate the leading parity-violating amplitude arising from one-loop pion graphs in chiral perturbation theory. An asymmetry of ∼ 5×10−8 is estimated for Compton scattering of 100 MeV photons.

Meson exchange in the weak decay of Λ hypernuclei and the Γ n / Γ p ratio

We take an approach to the Λ non-mesonic weak decay in nuclei based on the exchange of mesons. The one pion and one kaon exchange are considered, together with the exchange of two pions, either correlated, leading to an important scalar-isoscalar exchange (σ-like exchange), or uncorrelated (box diagrams). Constraints of chiral dynamics are used to generate these exchanges. A drastic reduction o...