A modular system of multigap proportional chambers

We describe a system of small multiwire proportional chambers having electrically separated adjacent gaps. The chambers can be stacked in any number and combination of planes

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

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 after the tube assembly an electromagnetic 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. (4 refs)

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

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 after the tube assembly an electromagnetic 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. (4 refs)

The system of forward-backward drift chambers in the UA2 detector

The system of multiplane drift chambers for the forward-backward toroidal spectrometers of the UA2 detector is described

The Pavia-Romal ATLAS MDT quality control system

The physics at LHC imposes very severe requirements on the ATLAS muon detector, which translates into stringent requirements on drift-tubes wire tensioning, leak current, gas leak and wire positioning. In order to verify all these parameters prior to chamber construction, a dedicated quality control system was completely designed and built by our groups. (1 refs)