Abstract
The neutron-rich nucleus ____nucleus{200}{Pt} is investigated via in-beam ____gamma-ray spectroscopy in order to study the shape evolution in the neutron-rich platinum isotopes towards the N = 126 shell closure. The two-neutron transfer reaction ____nucleus{198}{Pt}(____nucleus{82}{Se}, ____nucleus{80}{Se})____nucleus{200}{Pt} is used to populate excited states of ____nucleus{200}{Pt}. The Advanced Gamma Ray Tracking Array (AGATA) demonstrator coupled with the PRISMA spectrometer detects ____gamma rays coincident with the ____nucleus{80}{Se} recoils, the binary partner of ____nucleus{200}{Pt}. The binary partner method is applied to extract the ____gamma-ray transitions and build the level scheme of ____nucleus{200}{Pt}. The level at 1884____,keV reported by Yates et. al [Phys. Rev. C 37, 1889] was confirmed to be at 1882.1____,keV and assigned as the (6^+_1) state. An additional ____gamma ray was found and it presumably de-excites the (8^+_1) state. The results are compared with state-of-the-art beyond mean-field calculations, performed for the even-even ____nucleus{190-204}{Pt} isotopes, revealing that ____nucleus{200}{Pt} marks the transition from the ____gamma-unstable behaviour of lighter Pt nuclei towards a more spherical one when approaching the N=126 shell closure.