Eur. Phys. J. A (2005) 24: 259-274
https://doi.org/10.1140/epja/i2004-10144-3

Original Article

Gamma-ray spectroscopy in ¹¹⁰Sn and ¹¹¹Sn

¹ Heavy Ion Laboratory, Warsaw University, Pasteura 5A, 02-093, Warszawa, Poland
² Faculty of Physics, Warsaw University, Hoża 69, 00-681, Warszawa, Poland
³ The Andrzej Sołtan Institute for Nuclear Studies, PL-05-400 Otwock-Świerk, Świerk, Poland
⁴ Department of Physics, Silesia University, Katowice, Poland
⁵ Institut für Kernphysik, Forschungszentrum, D-52425 Jülich, Jülich, Germany
⁶ The H. Niewodniczański Institute of Nuclear Physics, 31-342, Kraków, Poland
⁷ Department of Physics, University of Łódź, ul. Pomorska 149/153, 90-286, Łódź, Poland

^* e-mail: jko@slcj.uw.edu.pl

Received: 9 August 2004
Accepted: 9 March 2005
Published online: 19 April 2005

Abstract

Excited states in ¹¹⁰Sn and ¹¹¹Sn nuclei have been investigated using in-beam γ-ray spectroscopic methods. An ¹⁶O beam with an energy of 60-80MeV was used to bombard a ⁹⁸Mo target. On the basis of the relative excitation functions, γ-ray angular distributions, γ-γ and γ-time distributions, γ-ray multiplicity and total energy data, the level schemes of ¹¹⁰Sn and ¹¹¹Sn have been studied and extended up to E _exc ∼ 11.5MeV, I = 24ℏ, and E _exc ∼ 11.1MeV and I = (51/2)ℏ, respectively. An extension of the intruder, g.s. and negative-parity bands, as well as 5 new band-like structures are proposed in ¹¹⁰Sn. The nature of newly introduced collective band 8 as well as 10⁺ states fed in the decay of the collective band is discussed. In the ¹¹¹Sn nucleus an intruder band based on the 23/2^- state has been reinvestigated and the extension of the g.s. band and second negative-parity band is given. Evidence for neutron-core coupling in ¹¹¹Sn is found. The structure and systematics of excited states in light Sn isotopes is discussed.