(p, t) Reaction studies on some even isotopes of samarium

Abstract

The (p, t) reaction on the even isotopes 144Sm, 148Sm and 15~ has been investigated at an incident proton energy of 25.5 MeV. Angular distributions have been measured for transitions to the ground state and excited states up to an excitation energy of about 2.5 MeV. Especially the L=0 angular distributions are discussed.The isotopes of samarium (Z= 62) seem to be very interesting for the investigation with two-neutron transfer reactions, since they cover a range from a closed neutron shell nucleus (144Sm, N= 82) with presumably spherical shape to a strongly deformed nucleus (154Sm, N=92). The sudden onset of a deformation around 152Sm has been shown to influence the two-neutron transfer reactions (see [1]). Apart from this effect the two neutron transfer reactions may be used as a probe for existing pairing correlations [2]. In fact, the (1, 1) pairing vibration states in the N= 82 nuclei 14~ and 142Nd have probably already been identified [3,4]. In samarium the situation is more difficult, since the neighbours of 144Sm, i.e. 14ZSm and 146Sm are not stable and were therefore not available as targets. Hence, pairing vibration, though possible, will not be discussed here. Detailed analysis of the angular distributions is not yet possible, since a description of a microscopic model wave function for the Sm nuclei is not known. The aim of our work is a systematic investigation of the rare earth region, using different reactions as tools to study the relevant properties. To begin with and for the reasons mentioned above we started out with the (p, t) reaction on the even isotopes of samarium 1448m, 1488m and 15~The measurements were carried out with the analysed beam of the Hamburg Isochron-Cyclotron. The tritons were detected by means of semiconducter telescopes. The experimental procedure has been fairly conventional and will be discussed elsewhere [5]. With the experimental setup an overall energy resolution of about 45 keV FWHM has been achieved to detect the outgoing tritons. The calibration of the analyser-* Work supported by the Bundesminister ftir Bildung und Wissenschaft.

Structure ofSm142from the decay ofEuKennedy1, Gujrathi2, Mark3 1975Phys. Rev. C274180View full textAdd to dashboardCite

“…In 1973 Oelert' performed (P, t) reaction studies on samarium isotopes and reported levels in ' 'Sm at 0 (0 ), 768+15 (2'), 1785+15 (4'), 2040+20 (2'), and 2358*20 keV.…”