On Excited States of Deuteron Nucleus

TL;DR

This paper investigates potential excited states of the deuteron nucleus, suggesting experimental evidence for dibaryon states and resonance interference, challenging the traditional view of deuteron as having no excited states.

Contribution

It provides experimental interpretation of peaks in cross-section data as evidence for deuteron excited states and dibaryons, supported by recent experimental findings.

Findings

Identification of a peak as a dibaryon state

Interpretation of another peak as N* resonance interference

Call for further experimental verification

Abstract

For a long time it was known that deuteron, as a weakly coupled nucleon pair, has no excited states. However, A.M. Baldin et al, commenting results of the first physical experiment with accelerated nuclei at JINR synchrophasotron, assumed as far back as in 1979 that one of peaks in a differential cross-section may arise due to an "excited state of deuterium". We have established that one of the peaks in the cross-section may be explained indeed in this way and corresponds to the dibaryon reported by WASA-at-COSY Collaboration. Another peak in the same region is interpreted most likely by interference of several $N^*$-resonances, and this possibility was also mentioned in the paper by A.M. Baldin et al. Further experimental studies based on modern experimental facilities and more abundant statistics are necessary to verify these observations.