120673376
Performance of the OPAL jet chamber
Abstract The jet chamber of the OPAL experiment at the LEP e + e − collider is designed to measure the direction and the momentum of charged particles as well as the specific energy loss in the chamber gas. The jet chamber has been operated at LEP since August 1989 and has recorded 500 000 hadronic decays of the Z 0 , resulting in a good understanding of the stability and systematics of the chamber. Resolutions obtained in the measurement of particle direction, momentum, and specific energy loss are presented, as well as the corrections and calibration procedures necessary to attain original design goals. A momentum resolution of 6.8% for particles with a momentum of 45 GeV/ c and an energy loss resolution of 3–4% over all momenta have been achieved.
196147152
Experience With the Jade Jet - Chamber at {PETRA} and Pattern Recognition Programs for the Jade Jet - Chamber
118362382
News from CERN, LHC Status and Strategy for Linear Colliders
This paper presents the latest development at CERN, concentrating on the status of the LHC and the strategy for future linear colliders. The immediate plans include the exploitation of the LHC at its design luminosity and energy as well as upgrades to the LHC (luminosity and energy) and to its injectors. This may be complemented by a linear electron-positron collider, based on the technology being developed by the Compact Linear Collider and by the International Linear Collider and/or by a high-energy electron-proton collider. This contribution describes the various future directions, all of which have a unique value to add to experimental particle physics, and concludes by outlining key messages for the way forward.
139392511
Results from DESY-Heidelberg NaI lead glass detector
118687763
The Future of the CERN Accelerator Complex
This chapter looks back at some of the most memorable achievements in high-energy physics during the 50 years spanning CERN's PS and LHC.
123302351
Results from the JADE Collaboration
Results from the JADE experiment at PETRA in the energy range between 27.7 and 35.8 GeV are reported. QED is tested using the reactions e+e− ⇒ e+e−, μ+μ−, γγ and lower limits on hypothetical cut‐off parameters of up to 100 GeV are obtained. Predictions of the standard electro‐weak theory are compared with the data and limits are derived on the values of the vector and axial vector coupling constants. Extended gauge models containing more than one neutral weak boson are also tested and lower limits are placed on the masses of such bosons.For the reaction e+e− ⇒ hadrons topological distributions of the hadrons are studied. At s√ of about 30 GeV it is shown in a model independent way that the observed planar events actually possess three‐jet structure strongly suggesting gluon bremsstrahlung as the origin of these events. By comparison of the data with the qqg — model we obtain a value for the strong coupling constant of αs (q2) = 0.17 ± 0.02 ± 0.05.At the highest energy of about 35 GeV a search for new flav...
56413579
A superconducting short period undulator for a harmonic generation FEL experiment
A three stage superconducting (SC) undulator for a high gain harmonic generation (HGE) FEL experiment in the infrared is under construction at the NSLS in collaboration with Grumman Corporation. A novel undulator technology suitable for short period (6-40 mm) undulators will be employed for all three stages, the modulator, the dispersive section and the radiator. The undulator triples the frequency of a 10.4 /spl mu/m CO/sub 2/ seed laser. So far a 27 period (one third of the final radiator) prototype radiator has been designed, built and tested.<<ETX>>
55001750
Design and construction of a high-duty factor photocathode electron gun
Under a joint collaboration between Grumman and BNL, a high-duty factor (>1%) photocathode electron gun is being constructed for use at the ATF facility at BNL. This gun was designed as the electron source for the proposed UV FEL Users' Facility at BNL. The thermally induced stresses exceed the yield strength of OFHC copper. For this reason, the gun is fabricated from GlidCop, an aluminum oxide dispersion strengthened copper alloy.<<ETX>>
118755074
Design and construction of a Compact Infrared Free Electron Laser CIRFEL
The 5-15 micron Grumman Compact Infra Red Free Electron Laser CIRFEL which will produce extremely short pulses of tunable radiation under construction is described. Electron pulses are produced at a repetition rate of up to 10 Hz by the illumination of a single crystal <001> LaB/sub 6/ photocathode with a photon injector, a 6-10 psec, 349 nm (frequency tripled Nd-YLF) laser mode locked to the 20th subharmonic of 2856 MHz. Photoelectrons are further accelerated and guided to the superconducting microwiggler by a robust beam transport system through an achromatic bend. The /spl sim/10 MeV electrons interact with the optical radiation inside a near symmetric laser cavity. The FEL output will be coupled out through a hole in one of the cavity mirrors. The CIRFEL system is expected to be delivered in 1994.<<ETX>>