N. V. Khomutov

Using the cathode surface of straw tube for measuring the track coordinates along the wire

The coordinate detectors based on straw tubes provide a high accuracy of the radial coordinate measurement using the drift time and a small amount of matter in the way of the measured particles. However, the measurement of the coordinate along the wire constitutes a problem. This paper proposes a method for measuring the hit coordinate along the wire with an accuracy better than 1 mm in a straw tube detector using the signals from the cathodes of the detector.

A small-power transistor divider for photomultiplier tubes

A high-voltage transistor voltage divider for photomultiplier tubes consists of a high-resistance linear resistive divider specifying potential distributions between dynodes and emitter followers maintaining this distribution. The divider features a low dissipation power and stable gain of the photomultiplier tube, when the average anode current varies in the entire measurement range.

2-D straw detectors with high rate capability

Precise measurement of straw axial coordinate (along the anode wire) with accuracy compatible with straw radial coordinate determination by drift time measurement and increase of straw detector rate capability by using straw cathode readout instead of anode readout are presented.

The use of a segmented cathode of a drift tube for designing a track detector with a high rate capability

Detector rate capability is one of the main parameters for designing a new detector for high energy physics due to the permanent rise of the beam luminosity of modern accelerators. One of the widely used detectors for particle track reconstruction is a straw-detector based on drift tubes. The rate capability of such detectors is limited by the parameters of readout electronics. The traditional method of increasing detector rate capability consists in increasing their granularity (the number of “elementary” detectors = readout channels) by reducing the straw diameter and/or by dividing the straw anode wire into two parts (for decreasing the rate per readout channel). A new method of designing straw detectors with a high rate capability is presented and tested. The method is based on dividing the straw cathode into parts and the independent readout of each part.

Detector with a profile-based cathode and the two-coordinate pad-strip readout system

A detector with a profile-based cathode and a two-coordinate cathode readout system has been experimentally investigated. Cathode pads located in each profile along the anode wire are diagonally interconnected, thus forming strips that cross the detector at some angle with respect to the anode wire. Owing to the availability of the two cathode coordinates and the coordinate associated with the anode wire, it is possible to solve the problem of identifying high-multiplicity events in a single detector.

Light output response of LYSO(Ce) crystal to relativistic helium and carbon ions

The light output response of LYSO(Ce) crystals was investigated using helium and carbon beams of 720 MeV and 3.48 GeV, respectively. Experimental results showed good agreement with the calculated curves by the Birks equation but the values of the parameters in the equation were different between helium and carbon ions.

A new detector system for the measurement of double differential cross sections of proton-actinide reactions in the 600-MeV region

A new detector system was proposed for the measurement of the double differential cross section (DDX) data on proton-actinide reactions in the 600-MeV region. The detector system is the combination of pulse height measurement and TOF measurement. In the pulse height measurement, conventional ΔE-E method was used with a plastic scintillator and an inorganic crystal. The TOF measurement was done by using two plastic scintillators. The result of the preliminary experiment carried out using 230 MeV/u helium beam is reported.

Test stands for mini drift tubes

The stands for testing mini drift tubes at the workshop of the Joint Institute for Nuclear Research are described. The test stands are used to perform persistent and effective quality control of detectors under conditions of mass production. Detectors manufactured for the D0 and COMPASS experiments have been tested on these stands.

Results of mass testing of mini drift tubes for the D0 forward muon system

The procedures and results of mass testing of mini drift tubes in the course of their production for the D0 forward muon system (Tevatron, Fermilab) are described. High-voltage training, checking the stability and uniformity of signals induced by X rays, measuring the wire tension, and leak testing are included in the testing procedure. Owing to the fast and effective testing of detectors under conditions of mass production, the quality of the mini drift tubes is such that virtually no tubes are finally rejected during assembly of the detector system.