DRCELL: A software package for drift chamber cell design

Designing a drift chamber cell geometry which optimizes resolution and two track separation is not a straightforward task. This paper describes a software package which helps visualize the behavior of drifting electrons within the cell under the influence of electric and magnetic fields. Histograms of chamber pulse shapes and arrival times may be generated. In addition, a calculation of the gas gain is performed. The package presently uses drift velocity, drift angle, gain, and dE/dx parameterizations for 50:50 argon/endash/ethane but modifications may be easily made for other gas mixtures. The model is straightforward and relies on an analytical form for the electric potential of an infinite series of wires. The electric field is calculated numerically in a small region surrounding any point of interest. In the absence of a magnetic field, the drift direction of an ionization electron is the unit vector along the E field direction. When a perpendicular magnetic field is present, the drift direction is rotated by the Lorentz angle, a. 3 refs., 2 figs., 1 tab

Horizontal band-saw

The effect of various parameters on the performance of the band saw when cutting mild steel-with a 10 t.p.i. raker-set blade were established over a limited range. These are discussed fully in the ‘conclusions'. With this limited survey it was not found possible to establish the optimum conditions of operation

Wide-angle elastic scattering and color randomization

Baryon-baryon elastic scattering is considered in the independent scattering (Landshoff) mechanism. It is suggested that for scattering at moderate energies, direct and interchange quark channels contribute with equal color coefficients because the quark color is randomized by soft gluon exchange during the hadronization stage. With this assumption, it is shown that the ratio of cross sections $R_{\overline{p} p/ p p}$ at CM angle $\theta = 90^0$ decreases from a high energy value of R_{\pbar p / pp} \approx 1/2.7, down to R_{\pbar p / pp} \approx 1/28, compatible with experimental data at moderate energies. This sizable fall in the ratio seems to be characteristic of the Landshoff mechanism, in which changes at the quark level have a strong effect precisely because the hadronic process occurs via multiple quark scatterings. The effect of color randomization on the angular distribution of proton-proton elastic scattering and the cross section ratio $R_{np/pp}$ is also discussed.Comment: 18 pages, latex2e, 4 uuencoded figures, include

Analysis of a Large Sample of Neutrino-Induced Muons with the ArgoNeuT Detector

ArgoNeuT, or Argon Neutrino Test, is a 170 liter liquid argon time projection chamber designed to collect neutrino interactions from the NuMI beam at Fermi National Accelerator Laboratory. ArgoNeuT operated in the NuMI low-energy beam line directly upstream of the MINOS Near Detector from September 2009 to February 2010, during which thousands of neutrino and antineutrino events were collected. The MINOS Near Detector was used to measure muons downstream of ArgoNeuT. Though ArgoNeuT is primarily an R&D project, the data collected provide a unique opportunity to measure neutrino cross sections in the 0.1-10 GeV energy range. Fully reconstructing the muon from these interactions is imperative for these measurements. This paper focuses on the complete kinematic reconstruction of neutrino-induced through-going muons tracks. Analysis of this high statistics sample of minimum ionizing tracks demonstrates the reliability of the geometric and calorimetric reconstruction in the ArgoNeuT detector