Trigger and measurement system for small-angle scattering

doi:10.1016/0168-9002(86)90637-6

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Volume 251, Issue 3, 1 November 1986, Pages 437-448

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Abstract

A system for measurement and selection of small-angle scattering was developed for the study of high-energy muon interactions with nuclei. The trigger decision was obtained by using the information from more than 500 individual scintillation counters placed in and around the beam. They were distributed in 8 successive planes upstream and 4 planes downstream of the target. In the trigger logic, each beam particle in the 5 cm wide beam was identified and, a fast trigger signal was produced, only if the track was consistent with a scattering process. The beam rate was ∼ 10⁷ s⁻¹ and the decision time of the trigger processor, built in the FASTBUS standard, was typically 80 ns. The reaction between 280 GeV muons and different target nuclei could be studied down to scattering angles of 1.6 mrad. The trigger rate with these conditions was of the order of 10⁻⁵ per incident beam particle.

References (12)

O.C. Allkofer
Nucl. Instr. and Meth.
(1981)
J.P. Albanese
Nucl. Instr. and Meth.
(1983)
J.P. Burq
Nucl. Phys.
(1981)
J.J. Aubert
Nucl. Instr. and Meth.
(1979)
O.C. Allkofer et. al.,...
Goodman
Phys. Rev. Lett
(1981)

There are more references available in the full text version of this article.

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Results are presented on the ratio of the inelastic muon-nucleus cross section per nucleon for carbon and calcium relative to that for deuterium. The measurements were made in the kinematic range of low x (0.003–0.1) and low Q² (0.3–3.2 GeV²) at an incident muon energy of 280 GeV. The calcium to deuterium ratio shows a significant x dependence which is interpreted as a shadowing effect. No strong Q² dependence is observed. This suggests that the effect is due at least partially to parton interactions within the nucleus.
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Trigger and measurement system for small-angle scattering

Abstract

Nucl. Instr. and Meth.

Nucl. Instr. and Meth.

Nucl. Phys.

Nucl. Instr. and Meth.

Phys. Rev. Lett