Measuring analyzing powers in the three-body break-up in the dd reaction using neutron detection with plastic scintillators

Abstract

We report on the analysis of analyzing power measurements for coplanar configurations in the three-body breakup of deuteron-deuteron (dd) scattering obtained with a polarized deuteron beam with a kinetic energy of 130 MeV. This analysis includes both the ²\(\textrm{H}(\vec {d},dp){n}\) and ²\(\textrm{H}(\vec {d},dn){p}\) processes. To identify the processes of interest, we reconstruct the neutron kinematics from the time-of-flight data provided by the plastic scintillators of Big-Instrument for Nuclear-Polarization Analysis (BINA). The timing information is used to determine the neutrons’ positions. Also, time-of-flight data, coupled with the laws of momentum and energy conservation is use5Pd to accurately deduce the energy of the neutrons. Also, particle identification technique is used to identify the dn combination of the ²\(\textrm{H}(\vec {d},dn){p}\) break-up reaction from the pn combination. Each step is meticulously validated by utilizing the protons from the ²\(\textrm{H}(\vec {d},dp)n\) reaction, which are analyzed as if they were neutrons in the ²\(\textrm{H}(\vec {d},dn)p\) reaction. The results of the analyzing powers of the ²\(\textrm{H}(\vec {d},dp){n}\) break-up reaction obtained using the procedure of the neutron-kinematics reconstruction, discussed in this paper, are presented as an overall cross-check and compared with the conventional results presented in Ramazani-Sharifabadi et al. (Eur Phys J A 56:221, 2020). Within the error bars no significant disagreement are observed between the analyzing powers of ²\(\textrm{H}(\vec {d},dp){n}\) and ²\(\textrm{H}(\vec {d},dn){p}\) processes which confirms the charge symmetry of nuclear force.