Different aspects of nuclear structure and reaction mechanisms in the collision ¹³N$\text{+}$¹¹B

Abstract

The reaction ¹³N$\text{+}$¹¹B has been investigated at two ¹³N beam energies: 29.5 and 45 MeV. Charged particles and $\text{γ}$ rays emitted in the reactions have been detected using a large array of silicon strip detectors and BaF${}_2$ scintillators, respectively. Several reaction channels have been analysed with different aims.

The proton transfer reaction ¹¹B(¹³N, ¹²C)¹²C to various excited states of ¹²C has been studied to obtain information on the ¹³N${}_{\mathrm{<mtext>g.s.</mtext>}}$ structure.

The excitation energy of the ²⁴Mg compound nucleus was in the region where several resonances occur in the ¹²C$\text{+}$¹²C system. The six-$\text{α}$ decay of the ²⁴Mg intermediate system has been studied. Some of these events have been identified as coming from the break-up of two ¹²C${}^{\mathrm{\ast }}$ in the 3${}^{\mathrm{-}}{}_1$–3${}^{\mathrm{-}}{}_1$ and 3${}^{\mathrm{-}}{}_1$–0${}^{\mathrm{+}}{}_2$ states.

The total fusion cross section has also been extracted from the data. In order to extract information on the isospin purity/mixing in ²⁴Mg at high excitation energy ($\text{E}{}_{\mathrm{<mtext>x</mtext>}}\text{∼47}$ MeV), the GDR $\text{γ}$ emission from this self-conjugate nucleus has been studied. A comparison of $\text{γ}$ spectra has been undertaken for the reactions ¹³N$\text{+}$¹¹B and ¹⁴N$\text{+}$¹⁰B.