Speaker
Prof.
Yury Uzikov
(Joint Institute for Nuclear Researches)
Description
At present as one of the most realistic candidate to dibaryon resonance
is considered the resonance $D_{IJ}=D_{03}$ observed by the WASA@COSY [1]
in the total cross
section of the reaction of two-pion production
$pn\to d\pi^0\pi^0$, here $I$ is the isospin and $J$ is the total angular momentum of this
resonance.
Very similar resonance structure was observed by ANKE@COSY in
the differential cross section
of the two-pion production reaction $pd\to pd \pi\pi$ 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 [2].
In the distribution over the invariant mass $M_{d\pi\pi}$ of the final $d\pi\pi$ system
the resonance peaks
were observed at $M_{d\pi\pi}\approx 2.38$~GeV [2]
that is the
mass of the isoscalar two-baryon resonance $D_{IJ}=D_{03}$,
while the kinematic conditions differ considerably from that in Ref. [1].
This data we analyzed in Ref. [3]
assuming
excitation of the $D_{03}$ resonance via t-channel $\sigma$-meson
exchange between the proton and deuteron and using
the two-resonance mechanism of the $D_{03}$ resonance decay [4].
The shapes of the distributions over the invariant masses
of the final $d\pi\pi$ and $\pi\pi$ systems were explained qualitatively in [3]
assuming the lowest values of the orbital angular momenta in the vertices $\sigma d\to D_{03}$ ($L=2$),
$D_{03}\to D_{12}+\pi$ ($l_1=1$), $D_{12}\to d+\pi$ ($l_2=1$).
In this work we study the role of higher orbital momenta in those vertices ($L=2,4,~l_1=1,3,5,~l_2=1,3$).
Furthermore, a possible contribution of the $D_{03}$ excitation to the $pd$-backward
elastic scattering is studied in the 1 GeV region.
[1] P. Adlarson et al. (WASA@COSY Collab.), Phys. Rev. Lett. 106, 242302 (2011).
[2] V. Komarov et al. (ANKE@COSY Collab.), Eur. Phys. J. A 54, 206 (2018).
[3] Yu. Uzikov, N.Tursunbayev, EPJ Web Conf. 204, 08010 (2019).
[4] M.N. Platonova, V.I. Kukulin, Phys. Rev. C 87, 025202 (2013).
Primary author
Prof.
Yury Uzikov
(Joint Institute for Nuclear Researches)
Co-author
Mr
Nurbek Tursunbayev
(JINR, DLNP)
