H.T. Blume

Beam tests and calibration of the H1 liquid argon calorimeter with electrons

Results are presented on the energy calibration of the H1 liquid argon calorimeter modules with electrons from a test beam in the energy range of 3.7 GeV to 80 GeV. The method to determine the calibration for the Hl experiment from these measurements by the use of detailed simulations is described . Various systematic checks of this calibration are given. The calorimeter response is uniform in space within ±1% and linear with energy within ±1%. An average energy resolution of about 11.5%/ E [GeV] is achieved .

Electron / pion separation with the H1 LAr calorimeters

Abstract The performances of the H1 liquid argon calorimeter modules for the energy measurements and identification of electrons are studied with test data taken at CERN in the energy range 5 to 166 GeV. Various electron identification estimators exploiting global or detailed shower characteristics are studied and compared. The usage of impact position measurements is also discussed. A best combination of robust shower estimators leads typically to π-misidentification probabilities in the range 1.5 to 5.0 × 10−3 at 30 GeV for 95% electron detection efficiency. This further reduces to ∼ 10−4 for these pions to be misidentified as electrons below 25 GeV.

Performance of a PbCu liquid argon calorimeter with an iron streamer tube tail catcher

A lead-copper calorimeter in liquid argon and an iron streamer tube calorimeter acting as a tail catcher have been tested with pions in the energy range of 30–230 GeV. Results are given on the energy resolution, on sampling fluctuations and on the space resolution of the liquid argon calorimeter. For the combined system an energy resolution of σE ≈ 0.5√E is obtained applying software weighting techniques and corrections for the dead material between the two calorimeters on an event to event basis. The remaining tails in the energy distributions are discussed.

Weak neutral-current effects in e/sup +/e/sup -/. -->. mu. /sup +/. mu. /sup -/ at 29 GeV

We present a measurement of the cross section for production of collinear muon pairs based upon a sample of more than 10,000 events observed in the MAC detector at PEP. From the asymmetry A/sub ..mu mu.. = -0.058 +- 0.010 we find the axial vector weak neutral coupling to be given by g/sub A//sup e/g/sub A//sup ..mu../ = 0.24 +- 0.04.