Dresden 2013 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HK: Fachverband Physik der Hadronen und Kerne
HK 19: Hadronenstruktur und -spektroskopie
HK 19.7: Vortrag
Montag, 4. März 2013, 18:30–18:45, HSZ-105
Resonance Multiplets in the Two-Baryon System — Dibaryons revisited*. — •Heinz Clement and Mikhail Bashkanov — Physikalisches Institut der Universität Tübingen
After Jaffe’s note on the possible existence of a bound six-quark system, the H-dibaryon denoting asymptotically a bound ΛΛ system, numerous theoretical investigations appeared predicting a vast number of states in the system of two baryons. In the subsequent experimental hunt for dibaryons many claims have been announced, however, none survived careful experimental investigations. The interest in dibaryons revived recently, when two groups announced that lattice QCD calculations provide evidence for a bound H-dibaryon. Also recently it has been noted that the double-pionic fusion reaction pn → dπ0π0 proceeds dominantly via a resonance structure observed in the total cross section at √s = 2.37 GeV with Γ ≈ 70 MeV and I(JP) = 0(3+) [1]. Since its decay proceeds dominantly via an intermediate ΔΔ system, this putative resonance constitutes asymptotically a ΔΔ system bound by nearly 100 MeV. In recent years also another resonance got established by SAID phase shift analyses, which resonates in the 1D2 pp partial wave at √s = 2.15 GeV with Γ ≈ 120 MeV. Since it resides just at the N Δ threshold, it is assumed to be a loosely bound (molecular) Δ N configuration. None of the many dibaryon predictions can predict both resonances at the proper energies – with the exception of Dyson’s multiplet prediction. The consequences will be discussed.
[1] P. Adlarson et al., Phys. Rev. Lett. 106 242302 (2011)
*supported by BMBF and COSY-FFE (FZ Jülich)