Speaker
Description
Short range correlated (SRC) NN pairs play an important role in structure of atomic nuclei and are studied in many nuclear centers using electron beams [1]. A new step was done at BM@N in JINR [2] where the reaction $^{12}$C+p→$^{10}$A+pp+N is studied using the $^{12}$C beam at energy of 4 GeV/nucleon at kinematics providing interaction of the hydrogen target with the SRC pair in the $^{12}$C. For theoretical analysis of the SRC effects in the reaction $^{12}$C+p→$^{10}$A+pp+N it seems natural to use a properly modified approach [3] developed earlier (see Ref. [4] and references therein) to describe the quasi-elastic knock-out of fast deuterons from the light nuclei $^{12}$C and $^{7,6}$Li by protons in the reactions (p,pd) and (p,nd) [5]. An elementary sub-process in the (p,Nd) was the backward elastic scattering of the proton on the two-nucleon clusters p$\{pn\}$→pd and p$\{nn\}$→nd at the proton beam energy 670 MeV. Spectroscopic amplitudes for NN-pairs in the ground state of the $^{12}$C nucleus are calculated here within the translation-invariant shell model (TISM) with mixing configurations. The factorization of the two-nucleon momentum distribution over the internal $n_{rel}(q_{rel})$ and the c.m.s. $n_{cm}(k_{c.m.})$ momenta is assumed and at large $q_{rel}$ the squared deuteron (or singlet deuteron) wave function is used for $n_{rel}(q_{rel})$. Relativistic effects in the sub-process p+$\{NN\}$➛p+N+N are taken into account in the light-front dynamics [3]. We found [6] that the c.m. distribution of the deuteron clusters obtained within the TISM and used in [3], [4] to describe the (p,Nd) data [4] has to be modified considerably to describe the $k_{c.m.}$ distribution of the SCR NN pairs measured in the electron data [1].The ratio of the spin-singlet to spin-triplet $\{NN\}_s$ pairs is calculated.
This work is supported in part by the RFBR grant № 18-02-40046.
1. E.O.Cohen et al., Phys. Rev. Lett. 121 (2018) 092501.
2. SRC@BMN proposal: http://bmnshift.jinr.ru/wiki/doku.php
3. Yu.N.Uzikov, Izv.RAN, Ser. Fiz. 84 (2020) 580.
4. M.A.Zhusupov, Yu.N.Uzikov, Fiz. El. Chast. At. Yadr. 18 (1987) 323.
5. J.Ero” et al., Nucl. Phys. A 372(1981) 317; D.Albrecht et al., Nucl.Phys. A 322 (1979) 512.
6. Yu.N.Uzikov, EPJ Web Conf., 222 (2019) 03027.
