M. Marino

Track reconstruction with a central two-shell scintillating fibre tracker (SFT)

Abstract We present a track reconstruction algorithm designed for the scintillating fibre tracker (SFT), having in view the upgrade of the L3 detector for LEP-II. This algorithm can also be applied for particle tracking at future hadron colliders. The tracking elements are polystyrene fibres of 60 μm diameter, which are arranged as fused coherent bundles into fibre layers. We study in particular a tracking setup, which consists of two concentric cylindrical shells each of 8 mm thickness, placed at r = 18.7 cm and r = 31.4 cm radius from the collider axis. The tracking reconstruction algorithm was tested with Monte Carlo generated e+ e− events at 185 GeV c.m. energy and comparing them with the reconstructed events. It achieves for particle momenta above 0.2 GeV/c a track reconstruction efficiency of nearly 100% for primary charged tracks with less than 1% contribution of ghost tracks. The average error on the reconstructed momenta for single tracks is around 3% and the average error on the reconstructed total momentum per event is around 6%.

Results on lead/scintillating fibres calorimetry

Abstract In the framework of the LAA project at CERN, the RD25 R&D group has built a fully projective, integrated electromagnetic and hadronic, lead/scintillating fibres compensating calorimeter prototype. The prototype consists of 41 modules, each made of a straight (or electromagnetic) and two wedged (or hadronic) sections, with a lead to fibres ratio of 4 to 1 in volume. We describe in this paper the performances of the calorimeter exposed to high energy electron and pion beams: results are presented on electromagnetic and hadronic energy resolution, position resolution and particle/particle separation in space. Prototype construction required the development of a technology, also described in this paper, which is directly scalable to the construction of a 4 π detector, intended to measure, localize and identify particles in a multi-TeV hadron collider experiment.

Neural networks for Higgs search

SummaryWe describe an approach to the heavy-Higgs (mH=750 GeV) search by means of a neural network (NN) in pp collisions at

Detector Simulation for Complex Multi-TeV Experiments

\sqrt s = 16

An entity relationship approach to the event and detector monte carlo simulation in high-energy physics

, TeV (LHC), 40 TeV (SSC) and 200 TeV (ELN/Eloisatron). The mechanisms we considered for Higgs production are gluon fusion and vector boson fusion, letting the H0 decay through the channel H0→Z0Z0→μ+μ-μ+μ-. The overall background to the Higgs signal was assumed to consist of the QCD continuum production of Z0 pairs, where each Z0 was forced to decay into muons. Using Monte Carlo simulated events at each energy, we trained a neural network to distinguish signal from background and evaluated its performances as an event classifier. The results are promising and indicate that neural networks could be efficiently used for event selection in future experiments at super-high energy.

A ‘Super Monte Carlo’ for Multi-TeV Physics Simulation

SummaryWe have defined a new Entity-Relationship (ER) database, called SUD (Set-Up Descriptor), which contains all the information needed to describe any kind of High Energy Physics apparatus for Monte Carlo simulation and real data analysis. SUD has been implemented using the ADAMO database management system. Different programs can access the data and their mutual relationships in a user-friendly way, via standard FORTRAN calls. As an example of application, the database has been interfaced with the GEANT tracking program.

Properties of Copper Cavities Coated with Niobium Using Different Discharge Gases

We have defined a new Entity-Relationship database which contains all the information needed to describe any kind of High Energy Physics apparatus. The database, called SUD (Set-Up Descriptor), has been implemented using the ADAMO database management system. Different programs can access the data and their mutual relationships in a user-friendly way, via standard FORTRAN calls. As an example of application, the database has been interfaced with the GEANT Monte Carlo program.

MEGA:Monte Carlo event generator adaptor

SummaryIn addition to a light Higgs (Mh≈0.1 TeV) a heavy one is expected (MH≈1 TeV). The knowledge of the two Higgs masses allows to predict the masses of as many as thirty sparticles expected in the simplest Supergravity theory. The production of a heavy Higgs (MH≫2MZ) is studied via Monte Carlo at three hadron supercollider energies: √s=16 TeV (LHC), √s=40 TeV (SSC) and √s=200 TeV (ELN/Eloisatron), for three masses:MH=500, 750, 1000 GeV. The 4-muon decay mode is investigated, in the presence of the «irreducible» background. The collider energy becomes a crucial parameter for the Higgs discovery as the Higgs mass increases. For a Higgs as heavy as 1 TeV the winning parameter is energy, not luminosity.