Speaker
Description
At present the resonance peak $D_{IJ} = D_{03}$ observed by WASA@COSY in the total cross section of the reaction of two-pion production in the isoscalar channel of the reaction pn → d$\pi^0\pi^0$[1], is considered as one of the most realistic candidate to the dibaryon resonance [2]. Here I=0 is the isospin and $J^P=3^+$ is the total angular momentum and parity of this resonance. A similar resonance structure was observed by ANKE@COSY in the differential cross section of the two-pion production reaction pd → pd$\pi\pi$ at beam energies 0.8-2.0 GeV with high transferred momentum to the deuteron at small scattering angles of the final proton and deuteron [3]. In this case the kinematic conditions differ considerably from that in Ref. [1] and two final pions not detected and, therefore, the isoscalar channel was not separated. Nevertheless, in the distribution over the invariant mass $M_{d\pi\pi}$ of the final $d\pi\pi$ system of the reaction pd → pd$\pi\pi$ the resonance peak was also observed at $M_{dππ}$ ≈ 2.38 GeV [3] that is the mass of the isoscalar two-baryon resonance $D_{03}$. In order to explain these data, in Refs. [4] the two-resonance model [5] of the reaction pn → d$\pi^0\pi^0$ was applied by inclusion of the t-channel σ-meson exchange between the proton and deuteron in the reaction pd → pd$\pi\pi$. Recently in Ref. [6] the reaction γ d→ d$\pi^0\pi^0$ was studied and an indication to excitation of isoscalar dibaryon resonance $D_{03}$(2380) and more heavier dibaryons d(2470) and d(2630) was found. These resonances can be excited also in the reaction dd→ dd* at SPD NICA collider. In this work we estimated the differential cross sections of the reactions dd → n+pd$\pi\pi$ (with pd → pd$\pi\pi$ subprocess) and dd → dd$\pi\pi$ assuming excitaion of the dibaryons by σ- meson exchange in t-channel as in Refs. [4] and distributions over the invariant mass of the final d$\pi\pi$ system for these reactions were calculated.
[1] P. Adlarson et al. (WASA@COSY Collab.), Phys. Rev. Lett. 106, 242302 (2011).
[2] H. Clement, Prog. Part. Nucl. Phys. 93 (2017) 195.
[3] V. I. Komarov et al. (ANKE@COSY Collab.), Eur. Phys. J. A (2018) 54: 206;
arxiv:1805.01493 [nucl-exp].
[4] Yu. Uzikov, N. Tursunbayev, EPJ Web of Conf. 204, 08010 (2019);
N. Tursunbayev, Yu. Uzikov, SciPost Phys. Proc. 3 (2020) 056.
[5] M.N. Platonova, V.I. Kukulin, Phys. Rev. C 87, 025202 (2013).
[6] T.C. Jude et al., Phys. Lett. B 832 (2022) 137277.
