Roper excitation inp→+α→p→+α+Xreactions

Roper excitation in ⃗p + α → ⃗p + α + X reactions

We calculate differential cross sections and the spin transfer coefficient D nn in the p+α → p+α+π 0 reaction for proton bombarding energies from 1 to 10 GeV and π 0 − p invariant masses spanning the region of the N * (1440) Roper resonance. Two processes – ∆ excitation in the α-particle and Roper excitation in the proton – are included in an effective reaction model which was shown previously ...

Roper excitation in the pp → ppπ 0 reaction close to threshold

A new mechanism for the pp → ppπ reaction close to threshold is suggested coming from the isoscalar excitation of the Roper and its decay into N(ππ)s−wave, with one of the π 0 emitted and the other one reabsorbed on the second nucleon. The mechanism can lead to important interference with other mechanisms and, together with experiment, serves to exclude large ranges of the 2π N decay parameters...

Projectile ∆ and target - Roper excitation in the p ( d , d ′ ) X reaction

In this paper we compare a model that contains the mechanisms of ∆ excitation in the projectile and Roper excitation in the target with experimental data from two (d, d ′) experiments on a proton target. The agreement of the theory with the experiment is fair for the data taken at T d = 2.3 GeV. The ∆ excitation in the projectile is predicted close to the observed energy with the correct width....

PaleoAmerican Ethnic Diversity by Billy Roper

Completing the Picture of the Roper Resonance.

We employ a continuum approach to the three valence-quark bound-state problem in relativistic quantum field theory to predict a range of properties of the proton's radial excitation and thereby unify them with those of numerous other hadrons. Our analysis indicates that the nucleon's first radial excitation is the Roper resonance. It consists of a core of three dressed quarks, which expresses i...