93634723
Contribution à l'étude du calorimètre électromagnétique à cristaux de germanate de bismuth de l'expérience L3 sur LEP
120522308
High energy cosmic muons and the calibration of the L3 electromagnetic calorimeter
Abstract A method to calibrate the L3 electromagnetic calorimeter with cosmic muons has been tested on a matrix of 100 tapered BGO crystals. Calibration constants in the energy range of 20–30 MeV were measured at the 2% level collecting about 200 muons per crystal. The results are in agreement with the calibration constant determined using a 10 GeV electron beam.
117191069
Higgs Search at LEP
121495790
Ionization loss in BGO
Abstract We report on a precise measurement of the energy loss through ionization by pions in bismuth germanate performed at several values of the incident particles momentum with a prototype of the L3 electromagnetic calorimeter. The experimental results are in good agreement with theoretical predictions showing the relativistic rise modified by density effect.
136953526
Performances of large BGO crystals below 20 MeV
120234331
Performances of a preamplifier-silicon photodiode readout system associated with large BGO crystal scintillators
Abstract The characteristics of a hybridized low noise preamplifier are described. Performances of the preamplifier in combination with silicon photodiodes are discussed and results from laboratory tests and test runs with an assembly of large BGO crystals are presented.
115884934
Operational experience with the LEP low-beta superconducting quadrupoles
118077361
The Superfluid Helium Cryogenic System for the LHC Test String: Design, Construction and First Operation
A major milestone in the preparation of the Large Hadron Collider (LHC) project is the testing and operation of a 50-m long superconducting magnet string, representing a half-cell of the machine lattice. This also corresponds to the length of the elementary cooling loops providing refrigeration at the 1.9 K, 4.5-to-20 K, and 50-to-75 K levels to the LHC cryomagnets. Based on existing large-capacity cryogenic infrastructure, we have designed, built and are operating a dedicated cryogenic system feeding the LHC Test String, with installed capacities of 120 W @ 1.8 K and 10 g/s supercritical helium at 4.5 K. The system also includes 15 kA, 1.6 kA, 500 A, 250 A and 50 A current lead pairs for powering of main and auxiliary magnet circuits, as well as a 120 kW liquid nitrogen vaporizer for controlled cooldown of the 105 kg cold mass. The system is fully instrumented, controlled by dedicated industrial PLCs connected to an industrial supervision system. We report on performance in operation, including response of the system to transients such as current ramp and discharge, as well as magnet resistive transitions.
135748369
COMPARED PERFORMANCE OF 'KAPTON' AND 'MYLAR' BASED SUPERINSULATION
134363806
Eight liquid helium cryostats for the superconducting magnets of the ISR high-luminosity insertion
97898730
Design of the dipole magnets for orbit correction in LEP
R6sume Le r6seau magn6tique du LEP c o n t i e n t 520 6lectro-aimants d i p o l a i r e s de cor rec t ion d ' o r b i t e dans l e s plans hor i zon ta l e t v e r t i c a l . La geom6trie des c i r c u i t s magnitiques e t l e s ca rac t6 r i s t iques des bobines d ' e x c i t a t i o n on t 6 t 6 cho is ies pour l e u r ap t i tude 2 repondre eff icacement e t 6conomiquement au cah i e r des charges (niveau e t q u a l i t 6 du champ) t o u t en respectant l e s contra int e s techniques impos6es par l e s grandes dimensions du LEP. Du f a i t de l a gamme de fonctionnement 6tendue des aimants, l a reduct ion des e f f e t s d8hys t6 r6s is a susc i t6 des e f f o r t s p a r t i c u l i e rs , conduisant 1 imposer des tolerances serrees sur l e champ c o e r c i t i f de l ' a c i e r u t i l i s 6 . Les r 6 s u l t a t s de mesures e l e c t r i ques, thermi ques e t magngtiques sur des mod51 es d'aimants sont prGsent6s.