Spectroscopy ofTh230in the(p,t)reaction

Abstract

The excitation spectra in the deformed nucleus 230 Th were studied by means of the (p,t) reaction, using the Q3D spectrograph facility at the Munich Tandem accelerator. The angular distributions of tritons are measured for about 200 excitations seen in the triton spectra up to 3.3 MeV. Firm 0 + assignments are made for 16 excited states by comparison of experimental angular distributions with the calculated ones using the CHUCK code. Additional assignments are possible: relatively firm for 4 states and tentative also for 4 states. Assignments up to spin 6 + are made for other states. Sequences of the states are selected which can be treated as rotational bands and as multiplets of excitations. Experimental data are compared with interacting boson model (IBM) and quasiparticlephonon model (QPM) calculations.

0+states and collective bands in228Th studied by the (p,Levon1, Graw2, Hertenberger3 et al. 2013Phys. Rev. CSelf Cite269700View full textAdd to dashboardCite

“…230 Th in our paper [6] after detailed analysis of the experimental data from the (p,t) reaction. For the 0 + excitation, we were able to derive additional information on the moments of inertia, which can be useful in clarifying the structure of these excitations.…”

“…For the calibration of the energy scale, the triton spectra from the reactions 184 W(p,t) 182 W, 186 W(p,t) 184 W and 234 U(p,t) 232 U were measured at the same magnetic settings. The levels in 230 Th known from the study [6] were also included in the calibration.…”

“…The corrections to the reaction energy are introduced depending on the excitation energy. For more details see [6].…”

“…2 transfer configurations to states with different spins were carried out in our previous paper [6]. The coupledchannel approximation (CHUCK3 code of Kunz [15]) was used in these calculations.…”

“…In the case of 230 Th, the assumption was made that the strongly excited first 0 + state, together with also strongly excited states with spins 2 + and 4 + , accompanied by somewhat weaker excited state with spin 6 + , belong to the two-phonon octupole quadruplet [6]. Strong excitations and close rotational parameters were the arguments for assigning the same structure to these states.…”