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The components, working principle and characteristics of FATIMA (FAst TIMing Array), a fast-timing detector system for DESPEC at FAIR, are described. The core system includes 36 LaBr 3 (Ce) scintillator detectors, a mounting frame for the DESPEC station and a VME-based fast-timing data acquisition system. The current electronic timing circuit is based on V812 constant fraction discriminators and V1290 time-to-digital converters. Gamma-ray energies are measured using V1751 digitisers. Characteristics of the core FATIMA system including efficiency, energy, and coincidence resolving time, as well as limitations, are discussed on the basis of test measurements performed in the S4 cave at GSI, Germany. The coincidence -time resolution for the prompt 60 Co cascade is determined to be ∼320 ps full width at half maximum. The total full energy peak efficiency at 1 MeV for the 36 detector array in the DESPEC setup is 2.9%. The energy-dependent prompt response centroid curve with the current CFD/TDC combination is shown to be smooth; the centroid shift method can be applied for the measurement of half-lives below 200 ps. An overview of applications of the FATIMA detectors as an ancilliary system in combination with other detector arrays during recent years is given. Data on the operation of the detectors in the presence of magnetic fields are presented.

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We present the results from an experiment dedicated to measure the lifetime of the 2 + 2 state, candidate for the one-phonon mixed-symmetry state, of 208 Po. This nucleus was studied in the α-transfer reaction 204 Pb( 12 C, 8 Be) 208 Po and the lifetime of the 2 + 2 state was determined by utilizing the Doppler-shift attenuation method. The experimental data show that the 2 + 2 state decays with a sizable M 1 transition to the 2 + 1 state revealing its isovector nature. Keywords Lifetimes • Electromagnetic transitions • Transfer reactions • 190≤ A ≤219

The transitional nuclei 132 Xe and 133 Xe are investigated after multinucleon-transfer (MNT) and fusionevaporation reactions. Both nuclei are populated (i) in 136 Xe + 208 Pb MNT reactions employing the highresolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the 136 Xe + 198 Pt MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a 130 Te(α,xn) 134−xn Xe fusion-evaporation reaction employing the HORUS γ -ray array at the University of Cologne. The high-spin level schemes are considerably extended above the J π = (7 − ) and (10 + ) isomers in 132 Xe and above the 11/2 − isomer in PHYSICAL REVIEW C 96, 024321 (2017) isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.

Abstract. The lifetimes of the 2