Nucleon-alpha elastic scattering analyses

Electromagnetic interactions in Halo Effective Field Theory

“…The curves also agree well with the ERE curve (thin solid line), which uses the ERE formula for the S 1/2 , P 3/2 , and P 1/2 partial waves and the numerical parameters from Ref. [33]. However, small deviations start to show up at E p ≈ 3.5 MeV, indicating an increasing importance of higher order terms as one goes higher in energy.…”

Cluster formation and the virial equation of state of low-density nuclear matter

“…2. The P 3/2 wave has a resonance at E ≈ 1 MeV with P 3/2 scattering length a P 3/2 = −62.95 fm 3 [39], and therefore will be the most important contribution to the Nα virial coefficient. The other partial waves are not resonant at low energies.…”

Effective field theory for halo nuclei: shallow -wave states

“…In Ref. [19], a phase-shift analysis including the 0+, 1−, and 1+ partial waves was performed and the effective-range parameters were extracted. The effective range expansion for a partial wave with orbital angular momentum l was given in Eq.…”

“…Elastic nα scattering is relatively well known experimentally. Since the nucleon has j = 1/2 and the α particle has j = 0, there are contributions from an s wave (s 1/2 ), two p waves (p 1/2 and p 3/2 ), etc.. Arndt, Long, and Roper performed a phase-shift analysis of low-energy data and extracted the effective range parameters in the s and p waves [19]. The p 3/2 partial wave displays a resonance at E ∼ 1 MeV corresponding to a shallow virtual bound state, while the s 1/2 and p 1/2 partial waves are nonresonant at low energies.…”