Construction of two large-size four-plane micromegas detectors

TL;DR

This paper details the construction and initial testing of large four-plane micromegas detectors, serving as prototypes for ATLAS muon system upgrades, emphasizing their resistive-strip technology and performance with cosmic rays.

Contribution

It introduces a new large-area micromegas detector design with resistive-strip technology and provides initial performance data for these prototypes.

Findings

Detectors are spark tolerant due to resistive-strip technology.

Successful measurement of two spatial coordinates with inclined strips.

Initial performance shows promise for muon system upgrade applications.

Abstract

We report on the construction and initial performance studies of two micromegas detector quadruplets with an area of 0.5 m$^2$. They serve as prototypes for the planned upgrade project of the ATLAS muon system. Their design is based on the resistive-strip technology and thus renders the detectors spark tolerant. Each quadruplet comprises four detection layers with 1024 readout strips and a strip pitch of 415 $\mu$m. In two out of the four layers the strips are inclined by $\pm$1.5$^{\circ}$ to allow for the measurement of a second coordinate. We present the detector concept and report on the experience gained during the detector construction. In addition an evaluation of the detector performance with cosmic rays and test-beam data is given.