The Born cross section for the process e þ e − → pp is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an integrated luminosity of 7.5 fb −1 , collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process e þ e − → pp and the proton effective form factor are determined in the pp invariant mass range between 2.0 and 3.8 GeV=c 2 divided into 30 intervals. The proton form factor ratio (jG E j=jG M j) is measured in 3 intervals of the pp invariant mass between 2.0 and 3.0 GeV=c 2 .
The production of J/ψ and Υ mesons in pp collisions at √ s = 8 TeV is studied with the LHCb detector. The J/ψ and Υ mesons are reconstructed in the µ + µ − decay mode and the signal yields are determined with a fit to the µ + µ − invariant mass distributions. The analysis is performed in the rapidity range 2.0 < y < 4.5 and transverse momentum range 0 < p T < 14 (15) GeV/c of the J/ψ (Υ ) mesons. The J/ψ and Υ production crosssections and the fraction of J/ψ mesons from b-hadron decays are measured as a function of the meson p T and y. The LHCb collaboration 27
IntroductionSuccessfully describing heavy quarkonium production is a long-standing problem in QCD. An effective field theory, non-relativistic QCD (NRQCD) [1,2], provides the foundation for much of the current theoretical work. According to NRQCD, the production of heavy quarkonium factorises into two steps: a heavy quark-antiquark pair is first created at short distances and subsequently evolves non-perturbatively into quarkonium at long distances. The NRQCD calculations depend on the colour-singlet (CS) and colour-octet (CO) matrix elements, which account for the probability of a heavy quark-antiquark pair in a particular colour state to evolve into a heavy quarkonium state. The CS model (CSM) [3,4], which provides a leading-order description of quarkonium production, was initially used to describe experimental data. However, it underestimates the observed cross-section for single J/ψ production at high transverse momentum (p T ) at the Tevatron [5]. To resolve this discrepancy, the CO mechanism was introduced [6]. The corresponding matrix elements were determined from the high-p T data, as the CO cross-section decreases more slowly with p T than that predicted by CS. More recent higher-order calculations [7][8][9][10] close the gap between the CS predictions and the experimental data [11], reducing the need for large CO contributions.
The new neutron spectrometer time-of-flight enhanced diagnostics (TOFED) for the EAST tokamak is presented and its characteristics are described in terms of simulation results, as well as the interface in the torus hall along with new neutral beam (NB) injectors. The use of TOFED for studies of the slowing down of NB-injected deuterons is illustrated. The implications of measuring the neutron emission on a long pulse machine are discussed together with the experimental challenges and diagnostic possibilities approaching those to be encountered in continuous operation.
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