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Lifetimes of excited nuclear states were determined in Ti-44 using the recoil distance Doppler-shift technique and the Doppler-shift attenuation method. Results from the K-pi = 3(-) band confirm isospin-symmetry breaking for the 3(1)(-) -> 2(1)(+) E1 transition. The lifetime of the 4(1)(-) state differs considerably from the previously known value. Good agreement is found for the 4(1)(+) and 6(1)(+) level lifetimes with respect to previous values. The experimental values are compared with large-scale shell-model calculations employing established interactions in the 0f1p shell, as well as a modern effective Hamiltonian including multiparticle multihole cross-shell configurations. Extended configuration spaces of this shell-model calculation allow for a detailed comparison with newly determined negative-parity states.

Shell model and multiparticle-multihole configuration-mixing calculations indicate a missing quadrupole collectivity needed to explain the transition strengths in the even-even Ne isotopes. Even with a significant scaling of the effective charges all details of the data cannot be reproduced. The effect is very pronounced in Ne-20(,22). Therefore new lifetime measurements in these nuclei were undertaken by us with the Doppler-shift attenuation method to recheck experimentally earlier findings. They confirmed the previous result in the case of Ne-20 while in Ne-22 the 2(1)(+) level lifetime was found to be shorter by 43%. It turned out that in the latter nucleus the lifetime of the 4(1)(+) level also has to be corrected. The B(E2;2(1)(+)-> 0(1)(+)) reduced transition strengths derived from the newly determined lifetimes as well as those for the heavier Ne isotopes are reasonably described by involving a mixing of a-cluster states of, e.g., the type alpha circle times 16O with normal, nearly spherical states. An extended version of the coupled-cluster effective interaction method published earlier describes well the spin dependence of the B(E2)'s in Ne-20.

The level lifetimes of the yrast 2(1)(+), 4(1)(+) and 6(1)(+) states and an upper limit of the lifetime of the 8(1)(+) state in Ti-46 have been measured with high accuracy exploiting the recoil distance Doppler-shift method (RDDS) and using coincidences. The nuclei were populated by the fusion evaporation reaction Ca-40(Be-9, 2p1n)Ti-46 at a beam energy of E=33 MeV at the FN tandem accelerator of the University of Cologne, Germany. Lifetimes were extracted using the established differential decay curve method (DDCM).

© 2018 The Chartered Society of Forensic Sciences The present study aimed at providing data to assess the secondary transfer of organic gunshot residues (OGSR). Three scenarios were evaluated in controlled conditions, namely displacing a firearm from point A to point B, a simple handshake and an arrest involving handcuffing on the ground. Specimens were collected from the firearm, the hands of the shooter and the non-shooter undergoing the secondary transfer in order to compare the amounts detected. Secondary transfer was observed for the three scenarios, but to a different extent. It was found that displacing a firearm resulted in secondary transfer in <50% of the experiments. The firearm also had an influence, as contrary to the pistol, no secondary OGSR were detected using the revolver. Shaking the hand of the shooter also transferred OGSR to the non-shooter's hand. In that case, the amount of OGSR was generally higher on the shooter than on the non-shooter. Finally, the largest secondary transfer was observed after the arrest with handcuffing with positive results in all cases using the pistol. In that scenario, the amounts on the shooter and the non-shooter were in the same range. This study highlights that the secondary transfer must be taken into account in the interpretation of OGSR. Indeed, an individual's hands might be contaminated by handling a firearm or having physical contact with a shooter.