Electron/pion separation with an Emulsion Cloud Chamber by using a Neural Network

We have studied the performance of a new algorithm for electron/pion separation in an Emulsion Cloud Chamber (ECC) made of lead and nuclear emulsion films. The software for separation consists of two parts: a shower reconstruction algorithm and a Neural Network that assigns to each reconstructed shower the probability to be an electron or a pion. The performance has been studied for the ECC of the OPERA experiment [1]. The $e/\pi$ separation algorithm has been optimized by using a detailed Monte Carlo simulation of the ECC and tested on real data taken at CERN (pion beams) and at DESY (electron beams). The algorithm allows to achieve a 90% electron identification efficiency with a pion misidentification smaller than 1% for energies higher than 2 GeV

"Tomography" of the cluster structure of light nuclei via relativistic dissociation

These lecture notes present the capabilities of relativistic nuclear physics for the development of the physics of nuclear clusters. Nuclear track emulsion continues to be an effective technique for pilot studies that allows one, in particular, to study the cluster dissociation of a wide variety of light relativistic nuclei within a common approach. Despite the fact that the capabilities of the relativistic fragmentation for the study of nuclear clustering were recognized quite a long time ago, electronic experiments have not been able to come closer to an integrated analysis of ensembles of relativistic fragments. The continued pause in the investigation of the "fine" structure of relativistic fragmentation has led to resumption of regular exposures of nuclear emulsions in beams of light nuclei produced for the first time at the Nuclotron of the Joint Institute for Nuclear Research (JINR, Dubna). To date, an analysis of the peripheral interactions of relativistic isotopes of beryllium, boron, carbon and nitrogen, including radioactive ones, with nuclei of the emulsion composition, has been performed, which allows the clustering pattern to be presented for a whole family of light nuclei.Comment: ISBN 978-3-319-01076-2. 55 pages, 28 figure

EQUIPMENT AND METHODS FOR AUTOMATIC TRACK ANALYSIS

A comprehensive program has been initiated at the University of California Radiation Laboratory to give practical aid to the physicists and technicians carrying out track measurements. Attention has been given to stack alignment, coordinate read-out, grain-density measurement, multiple-scattering measurements, and data recording. (A. C.

DATA FOR ELEMENTARY-PARTICLE PHYSICS

S>Tables of elementary-particle data in easily accessible form are presented for researchers in highenergy physics. Included are: The Masses used Mean Lives of the Elementary Particles; Atomic and Nuclear Properties of Materials; Particle Scattering; atomic and Nuclear Constants; and Particle Decay and Reaction Dynamics. (T.R.H.

DATA FOR ELEMENTARY-PARTICLE PHYSICS

S>Tables of elementary-particle data in easily accessible form are presented for researchers in highenergy physics. Included are: The Masses used Mean Lives of the Elementary Particles; Atomic and Nuclear Properties of Materials; Particle Scattering; atomic and Nuclear Constants; and Particle Decay and Reaction Dynamics. (T.R.H.

Range Energy Relation for Protons in Nuclear Emulsions

An experimental range-energy relation in Ilford C-2 emulsion has been obtained for proteins up to 39.5 Mev. In the region from 17 to 33 Mev the relation for dry emulsion is fitted by the empirical equation E{sub (MeV)} = 0.251 R{sub ({mu})} 0.581. Variations in water content due to changes in atmospheric humidity make several percent difference in range. The range in Ilford glass is found to be 18 {+-} 4 percent longer than in dry C-2 emulsion