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Fachbereich Physik. CERN Courier September 2011. Resonance Multiplets in the Two-Baryon System --- Dibaryons Revisited. MesonNet Meeting Prague, June 17 - 19, 2013. Heinz Clement. Two-Baryon Scenario. Known knowns: 3 S 1 deuteron groundstate: I (J P ) = 0 (1 + )
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Fachbereich Physik CERN Courier September 2011 Resonance Multiplets in the Two-Baryon System --- Dibaryons Revisited MesonNet Meeting Prague, June 17 - 19, 2013 Heinz Clement
Two-Baryon Scenario • Known knowns: • 3S1 deuteron groundstate: I (JP) = 0 (1+) • 1S0 virtual state (NN FSI): I (JP) = 1 (0+) • Known unknowns: • Are there six-quark bags (genuine dibaryons)? • Are there in general resonant states (molecular, dynamic) at all? • Recent experimental findings: • 1D2 resonance near the DN threshold: I (JP) = 1 (2+) • ABC resonance structure much below the DD threshold: I (JP) = 0 (3+) • Are there more states? • Model predictions • Dyson‘s multiplet Resonances in the Two-Baryon System
The 1D2 Resonance • Best seen in pp dp+, • but also in pp pnp+ as well as pp and p+d scattering (phaseshift analyses) stot(p+d pp) Argand plot R.A. Arndt et al., PRC 48 (1993) 1926 50 (1994) 1796 56 (1997) 635 N. Hoshizaki, PRC 45 (1992) R1424 Prog. Theor. Phys. 89 (1993) 245 251 563 569 I (JP) = 1 (2+) M = 2144 MeV = mD + mN – 26 MeV G = 110 MeV GD Alternative dynamic description: Diss. C.A. Mosbacher, Bonn 1998 Resonances in the Two-Baryon System
The ABC Resonance I (JP) = 0 (3+) M 2370 MeV 2mD – 90 MeV “ABC resonance” • 70 MeV ≤1/3 GDD intr50 MeV See talk M. Bashkanov Phys.Rev.Lett.106, 242302 (2011) Resonances in the Two-Baryon System
Δ π d π Δ pn R DD dp0p0 model p n I (JP) = 0 (3+) M, G, Gi * Gf , F(qDD) Mdp0 Phys.Rev.Lett.106, 242302 (2011) Mpp Qd* ABC effect Resonances in the Two-Baryon System
s(pN d p p ) I = 0 + 1 s(pn d p+p-) I = 1 2 s(pn d p0p0) I = 0 ½ s(pp d p+p0) COSY Annual Report 2012 Phys. Lett. B721 (2013) 229 Resonances in the Two-Baryon System
Status of the ABC Resonance See talk M. Bashkanov decay channel branching status ------------------------------------------------------------------------ d p0p015 % observed d p+p- 25 % observed ppp0p- 7 % observed npp0p0 (12 %, predicted*) data analysis WASA npp+p- (31 %, predicted*) data analysis HADES np (10 %, predicted) data analysis WASA * Fäldt & Wilkin, PLB 701 (2011) 619 Albaladejo & Oset, arXiv:1304.7698 [nucl-theor] first results very encouraging! Resonances in the Two-Baryon System
Comparison to predictions from Quark Models Experiment Bag Model QDCSM ChQM SU(6) Mulders et al. Goldman, Ping et al. Huang, Shen et al. Dyson PRD 21 (1980) 2653 PRC 79 (2009) 024001 Mod.Phys.Lett.A25(2010)2155 PRL 13 (1964) 815 E … … DD 3+ 2+ DN … … 1+ 0+ NN I = 0 1 0 1 0 1 0 1 0 1 Resonances in the Two-Baryon System
… inevitable dibaryon: unique symmetry! Resonances in the Two-Baryon System
… inevitable dibaryon I(JP) = 0(3+) state: totally symmetric in space, spin & color antisymmetric in isospin accessed via DDas doorway ? D D N N d* Np Np Resonances in the Two-Baryon System
Dyson‘s Multiplet Prediction Resonances in the Two-Baryon System
Dyson‘s Prediction State I J Asymptotic Configuration mtheor [MeV] mexp [MeV] Gexp [MeV] --------------------------------------------------------------------------------------------------------------------------------- D01 0 1 Deuteron 1876 1876 D10 1 0 virtual 1S0 1876 1878 D12 1 2 NN(1D2) DN NNp 2160 2144 110 D21 2 1 DN NNp 2160 ? ? D03 0 3 NN(3D3) DD NNpp 2350 2370 70 D30 3 0 DD NNpp 2350 ? ? --------------------------------------------------------------------------------------------------------------------------------- Resonances in the Two-Baryon System
Dyson‘s Prediction State I J Asymptotic Configuration mtheor [MeV] mexp [MeV] Gexp [MeV] --------------------------------------------------------------------------------------------------------------------------------- D01 0 1 Deuteron 1876 1876 D10 1 0 virtual 1S0 1876 1878 D12 1 2 NN(1D2) DN NNp 2160 2144 110 D21 2 1 DN NNp 2160 ? ? D03 0 3 NN(3D3) DD NNpp 2350 2370 70 D30 3 0 DD NNpp 2350 ? ? --------------------------------------------------------------------------------------------------------------------------------- Resonances in the Two-Baryon System
A hint for D21 I(JP) = 2(1+) ? • Pionic Double Charge Exchange in Nuclei: • non-analog transitions: intermediate system: (DN)I=2, JP=1+ M 2150 MeV G 90 MeV A. Wirzba et al., PRC 40 (1989) 2745 M.B. Johnson, L.S. Kisslinger, PLB 168 (1986) 26 J. Draeger et al., PRC 62 (2000) 064615 Resonances in the Two-Baryon System
Conclusions • Non-Strange Two-Baryon Spectrum • 3 established states: 3S1 deuteron groundstate 1S0 virtual state 1D2 resonance (DN) • 1 new - possibly exotic - candidate: ABC resonance (DD) • Are there more states? • NN-decoupled states with I = 2, 3? • Search in pp ppp+ p- and in pp ppp+p+p-p- Dyson‘s prediction E DD 0+ 3+ 1+ 2+ DN 1+ 0+ NN I = 0 1 2 3 Resonances in the Two-Baryon System
Comparison to predictions from Quark Models Experiment Bag Model QDCSM ChQM SU(6) Mulders et al. Goldman, Ping et al. Huang, Shen et al. Dyson PRD 21 (1980) 2653 PRC 79 (2009) 024001 Mod.Phys.Lett.A25(2010)2155 PRL 13 (1964) 815 E … DD 3+ 2+ DN … 1+ 0+ NN I = 0 1 0 1 0 1 0 1 0 1 Resonances in the Two-Baryon System