Uncertainties in track momentum due to multiple scattering in a forward spectrometer

The influence of multiple scattering on the momentum resolution for a forward spectrometer is investigated. Two cases, with and without track measurements inside the magnet, are discussed. A simple relation between angular and momentum resolutions and multiple scattering inside the magnet is derived and confirmed with Monte Carlo generated events subjected to a detailed simulation and full reconstruction for a real spectrometer. (orig.)Available from TIB Hannover: RA 2999(2002-151) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Bremsstrahlung in leptonic onia decays: effects on mass spectra

In this note we present a study of the radiative tails in the invariant mass spectra of muon or electron pairs from J/#psi#, #psi#(2S) and #gamma#(1S) decays which is due to an additional emission of a photon. An analytic formula for dilepton mass spectra in radiative decays is derived and a monte carlo simulation for realistic detector conditions is used to study effects on the spectra. A rather simple parameterisation is given, suitable for the treatment of real data. (orig.)Available from TIB Hannover: RA 8919(04-105) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

The concurrent track evolution algorithm: extension for track finding in the inhomogeneous magnetic field of the HERA-B spectrometer

The concurrent track evolution method, which was introduced in a previous paper, has been further explored by applying it to the propagation of track candidates into an inhomogeneous magnetic field volume equipped with tracking detectors, as is typical for forward B spectrometers like HERA-B or LHCb. Compared to the field-free case, the method was extended to three-dimensional propagation, with special measures necessary to achieve fast transport in the presence of a fast-varying magnetic field. The performance of the method is tested on HERA-B Monte Carlo events with full detector simulation and a realistic spectrometer geometry. (orig.)15 refs.Available from TIB Hannover: RA 2999(98-142) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman