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␥ rays following the 160 Dy( 36 Ar,4n͒ 192 Po reaction have been identified by employing a high-transmission gas-filled separator in recoil decay tagging measurements. The deduced level scheme reveals a flattening of the energy systematics, when going towards the neutron midshell indicating that the deformed intruder structures have become yrast. ͓S0556-2813͑96͒50212-8͔ PACS number͑s͒: 27.80.ϩw, 23.20.Lv, 21.60.Ev, 25.70.Ϫz The microscopic origin of quadrupole collectivity at lowexcitation energies in neutron midshell nuclei near the Zϭ50 and Zϭ82 shell closures is not well known. In some of these nuclei, deformed intruder states coexist with nearly spherical normal states ͓1͔, while for example in the evenmass Cd nuclei the intruder structures clearly play a role in generating low-lying quadrupole phonon states ͓2͔. These intruder structures are usually associated with two-proton excitations across the main shell gap, but recently the importance of deformation driving high-j neutron orbitals in these states has also been pointed out ͓3-5͔.In this respect, the Po nuclei with two protons outside the Zϭ82 shell closure form an interesting series of isotopes. The ␣and ␤-decay studies by the Leuven group ͓6-9͔ strongly support the view that the abrupt drop of level energies in light even-mass Po isotopes is due to proton 4p-2h intruder configurations while in recent calculations by the Rutgers group ͓4,5͔ this behavior is quite well reproduced by taking into account neutron orbitals, especially the i 13/2 .In order to resolve the ambiguities discussed above, it is crucial to extend the Po energy-level systematics towards the neutron midshell. However, as a consequence of strong fission competition, the fusion-evaporation reaction channels for populating the midshell Po nuclei become very weak and, therefore, special triggering methods are needed.In the present work we describe in-beam ␥-ray studies of 192 Po ͓10͔ by using the recoil decay tagging method ͓11,12͔.A recent determination of the half-life of its ␣-decaying ground state gave a value of 33.2͑14͒ ms ͓9͔. No excited states in 192 Po have been identified before our work. The experiments were performed at the Accelerator Laboratory of the University of Jyväskylä ͑JYFL͒. A beam of 178 MeV 36 Ar ions from the JYFL K130 cyclotron was used to bombard a 70% enriched 500 g/cm 2 thick 160 Dy target. The 192 Po nuclei of interest were produced via the 4n-evaporation channel. Prompt ␥ rays from the target were detected by the DORIS array consisting of 9 TESSA type ͓13͔ Compton suppressed Ge detectors in a truncated dodecahedron frame. The efficiency of the array is about 0.6% at 1.3 MeV.The gas-filled recoil separator RITU ͓14͔ was used to separate fusion-evaporation residues from the dominant fission background. RITU is a charge and velocity focusing device, especially designed for collecting recoiling fusionevaporation residues with high efficiency. Recoils were implanted into an 80ϫ35 mm Si strip detector covering about 70% of the recoil distribution at the fo...