Search for tribaryon production in alpha-particles interactions with protons at intermediate energies

TL;DR

This study investigates the production of tribaryon states in alpha-particle interactions with protons at intermediate energies, revealing narrow structures in the mass spectra that suggest possible tribaryon resonances.

Contribution

It provides experimental evidence of narrow structures in the trinucleon mass spectra, supporting the existence of low-lying tribaryon resonances predicted by theories.

Findings

Narrow structures observed at 2.99 GeV and 3.04 GeV in mass spectra.

Structures are consistent with theoretical tribaryon resonance predictions.

Possible resonance nature of the observed structures discussed.

Abstract

The analysis of the data on the reactions $^4$Hep -> pppnn and $^4$Hep -> dppn obtained at the 2-m ITEP liquid-hydrogen bubble chamber exposed to beams of $^4$He nuclei with momenta of 2.7 and 5 GeV/c revealed a narrow structures in the effective-mass spectra of the trinucleon system (NNN) at 2.99 GeV (for isospin T=3/2) as well as at 3.04 GeV (T=1/2). The masses of the observed structures are consistent with the masses of low-lying tribaryon resonances predicted by some theoretical models. Possible resonance nature of the structures observed is discussed.