T=3/2 states in ¹³C

Background: Experimental information on the structure of low-lying levels with isospin 3/2 in systems with 13 nucleons can be used to evaluate the quality of modern theoretical predictions for the light exotic systems. This level structure is poorly known at present. Purpose: Search for T=3/2 states in ¹³C was performed in this work. Method: These states were observed in the resonance elastic scattering of radioactive beam ¹²B on protons using the thick target inverse kinematics technique. Results: Six new states in ¹³C were identified as T=3/2 states. Tentative spin-parity assignments are suggested. Comparison to the previous knowledge of the level structure of T=3/2 A=13 system and to shell-model predictions is given. Conclusion: The elastic scattering of neutron-rich beams on proton target is a convenient tool for isobaric analog states search. The observed ¹²B+p excitation function is determined by the T=3/2 states and no features associated with T=1/2 states were found. Although the level scheme of T=3/2 states in A=13 systems is still far from being complete the emerging picture shows significant disagreements with predictions of contemporary shell models.