Observation of inverse diproton photodisintegration at intermediate energies

Abstract

The reaction pp->{pp}_sγ, where {pp}_s is a proton pair with an excitation energy E_{pp}<3 MeV, has been observed with the ANKE spectrometer at COSY-Juelich for proton beam energies of T_p=0.353, 0.500, and 0.550 GeV. This is equivalent to photodisintegration of a free 1S_0 diproton for photon energies Eγ~ T_p/2. The differential cross sections measured for c.m. angles 0 deg.<θ_{pp}<20 deg. exhibit a steep increase with angle that is compatible with E1 and E2 multipole contributions. The ratio of the measured cross sections to those of np->dγis on the 10^{-3}-10^{-2} level. The increase of the pp->{pp}_sγcross section with T_p might reflect the influence of the Delta(1232) excitation.

arXiv comment4 pages + 4 figures

References in corpus (7)

• Updated analysis of NN elastic scattering to 3 GeV
• Electromagnetic structure of the deuteron
• Onset of asymptotic scaling in deuteron photodisintegration
• Production of the 1S0 diproton in the pp -> pp pi0 reaction at 0.8 GeV
• Complete measurement of three-body photodisintegration of 3He for photon energies between 0.35 and 1.55 GeV
• Hard Photodisintegration of a Proton Pair in 3He
• Energy dependence of forward 1S0 diproton production in the pp -> pp pi0 reaction

Cited by in corpus (5)

• Energy dependence of hard bremsstrahlung production in proton-proton collisions in the Delta(1232) region
• Hard bremsstrahlung in the pp -> pp gamma reaction
• Gauge-invariant formulation of $NN\to NN\gamma$
• Measurement and analysis of the pp -> pp gamma reaction at 310 MeV
• A model-independent analysis of p + p --> pp(1S0) + gamma