118813308
Plans for experiments protection at the LHC
The Large Hadron Collider (LHC), once in operation, will represent approximately a 200-fold increase in stored beam energy with respect to previous high energy colliders. Safe operation will critically rely on machine and experiment protection systems. We describe the general experiment protection strategy against beam failures with some emphasis on silicon vertex detectors of the LHC experiments.
118883948
FURTHER REMARKS ON THE $Sigma$ PARITY
Answers are given to some recent criticisms of the EPSILON parity determination made at the Lawrence Radiation Laboratory. (auth)
103525244
Quasielastic electron scattering from polarized He-3.
121311258
Design and construction of high-frequency transition units for polarized deuterium internal targets
Abstract Radio-frequency transition units have been developed in order to produce vector and tensor polarized atomic deuterium beams. Transitions between various hyperfine states were generated using both a medium field transition unit and a resonant cavity structure as a strong field transition unit. Tests were carried out to determine the transition efficiencies of these units as function of radio frequency power, strength of the magnetic holding field, magnetic field gradient, and for the strong field unit, also as function of the position of the atomic beam in the cavity structure. A Stern—Gerlach source equipped with a medium and a strong field unit will provide a tensor polarized deuterium beam with the highest figure of merit at the minimum number of transition units. This polarization scheme allows for rapid reversal of tensor polarization while keeping the vector polarization fixed, and vice versa. The performance of the high-frequency transition units is described well by the results of a quantum-mechanical calculation. We will demonstrate that in a realistic internal target environment the efficiencies for the transitions between the 1–4, 2–6, and 3–5 hyperfine states exceeded in all cases 90% of the theoretical maximum polarization.
123641336
Recoil detection with a polarized He-3 target
Abstract The ultra-thin gas targets used in storage ring internal target experiments allow low energy, heavy nuclei to emerge from the target region. A detector capable of analyzing these nuclei provides unique access to many nuclear reactions. We report here the first use of such a detector in conjunction with a polarized 3 He internal target and a polarized electron beam. The results of using the detector as a luminosity monitor and as a polarimeter to measure the product of beam and target polarizations are presented. The ability to study coherent pion production via the reactions 3 He → ( e → , e ′ 3 He )π 0 and 3 He → ( e → , e ′ 3 H )π + is shown along with the ability of the detector to unambiguously separate the two- and three-body breakup channels of the reaction 3 He → ( e → , e ′p) .
121914137
DECAY MODES AND WIDTH OF THE /eta/ MESON
Author(s): Bastien, Pierre L.; Berge, J. Peter; Dahl, Orin I.; Ferro-Luzzi, Massimiliano; Miller, Donald H.; Murray, Joseph J.; Rosenfeld, Arthur H.; Watson, Mason B.
208345688
VELO Geometry Optimisation
New possible layouts of the LHCb Vertex Locator (VELO) have been compared with the existing baseline design outlined in the Technical Proposal. Based on a comparison of essential figures of merit, namely vertex resolutions, event selection efficiencies, trigger performance, and technical constraints an updated baseline design is proposed. The new design retains the same number of electronic channels as that in the Technical Proposal, but has an increased number of measuring stations (25 rather than 17) with a reduced inner radius (8mm rather than 10mm).
114023912
Performance of a wide pitch n-on-n silicon detector with floating strips
122010968
LUMINOSITY MONITORING AT LHCb