An electromagnetic micrometer to measure the wire centering in high-resolution aluminium drift tubes

Author

Cambiaghi, M. ; Cardini, A. ; Casani, S. ; Ferrari, R. ; Gaudio, G. ; Iuvino, G. ; Lanza, A. ; Prata, M.

Author_Institution

Dipt. di Fisica Nucl. e Teorica, Pavia Univ., Italy

Volume

47

Issue

3

fYear

2000

fDate

6/1/2000 12:00:00 AM

Firstpage

784

Lastpage

788

Abstract

The muon detector of the ATLAS experiment at LHC (CERN) consists of 370000 high-resolution drift tubes assembled in multi-layer chambers. To take full advantage of the single-tube resolution, the high-precision external surface of tube end-plugs is used for positioning a layer before gluing. The wire position in the tube is defined at construction time by means of a locator inserted in the end-plug. To check that the wire is in the nominal position alter the tube assembly an Electro-Magnetic MIcrometer (EMMI) has been developed. EMMI detects the wire position by measuring the electromotive force induced in two sensors symmetrically placed on both sides of the tube when a small sinusoidal current circulates on the wire. An accuracy of two microns on the wire centering has been obtained. The simplicity of this method and the short measuring time allow every drift tube to be checked, thus guaranteeing the precision requested for the ATLAS muon detector

Keywords

drift chambers; micrometry; muon detection; position measurement; ATLAS experiment; ATLAS muon detector; Al; electromagnetic micrometer; electromotive force; high-precision external surface; high-resolution aluminium drift tubes; high-resolution drift tubes; multi-layer chambers; single-tube resolution; tube end-plugs; wire centering; Assembly; Current measurement; Detectors; Electromagnetic measurements; Force measurement; Force sensors; Large Hadron Collider; Mesons; Position measurement; Wire;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/23.856516

Filename

856516