Abstract: ATLAS measurements of two-particle correlations are presented for root s = 5.02 and 13 TeV pp collisions and for root(NN)-N-s = 5.02 TeV p + Pb collisions at the LHC. The correlation functions are measured as a function of relative azimuthal angle Delta phi, and pseudorapidity separation Delta eta, using charged particles detected within the pseudorapidity interval |eta| < 2.5. Azimuthal modulation in the long-range component of the correlation function, with | Delta eta| > 2, is studied using a template fitting procedure to remove a “back-to-back” contribution to the correlation function that primarily arises from hard-scattering processes. In addition to the elliptic, cos(2 Delta phi), modulation observed in a previous measurement, the pp correlation functions exhibit significant cos(3 Delta phi) and cos(4 Lambda phi) modulation. The Fourier coefficients v(n),(n) associated with the cos (n Lambda phi) modulation of the correlation functions for n = 2-4 are measured as a function of charged-particle multiplicity and charged-particle transverse momentum. The Fourier coefficients are observed to be compatible with cos(n phi) modulation of per-event singleparticle azimuthal angle distributions. The single-particle Fourier coefficients vn are measured as a function of charged-particle multiplicity, and charged-particle transverse momentum for n = 2-4. The integrated luminosities used in this analysis are, 64 nb(-1) for the root s = 13 TeV pp data, 170 nb(-1) for the root s = 5.02 TeV pp data, and 28 nb(-1) for the root(NN)-N-s = 5.02 TeV p + Pb data.

Abstract: The accurate determination of the response function of organic scintillation neutron detectors complements their experimental characterization. Monte Carlo simulations with GEANT4 can reduce the effort and cost implied, especially for complex detection systems for which the characterization is more challenging. Previous studies have reported on the inaccuracy of GEANT4 in the calculation of the neutron response of organic scintillation detectors above 6 MeV, due to an incomplete description of the neutron-induced alpha production reactions on carbon. We have improved GEANT4 in this direction by incorporating models and data from NRESP, an excellent Monte Carlo simulation tool developed at the Physikalisch-Technische Bundesanstalt (PTB), Germany, for the specific purpose of calculating the neutron response function of organic scintillation detectors. The results have been verified against simulations with NRESP and validated against Time-Of-Flight measurements with an NE213 detector at PTB. This work has potential applications beyond organic scintillation detectors, to other types of detectors where reactions induced by fast neutrons on carbon require an accurate description.

Abstract: The transitional nuclei Xe-132 and Xe-133 are investigated after multinucleon-transfer (MNT) and fusionevaporation reactions. Both nuclei are populated (i) in Xe-136 + 2(08P)b MNT reactions employing the highresolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe-136 + Pt-198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te-130(alpha, xn) Xe134-xn fusion-evaporation reaction employing the HORUS gamma-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the J(pi) = (7(-)) and (10+) isomers in Xe-132 and above the 11/2(-) isomer in Xe-133. The results are compared to the high-spin systematics of the Z = 54 as well as the N = 78 and N = 79 chains. Furthermore, evidence is found for a long-lived (T-1/2 >> μs) isomer in Xe-133 which closes a gap along the N = 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.