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arXiv · 0908.1562

ATLAS Monitored Drift Tube Chambers in E = 11 MeV Neutron Background

T. Mueller·A. Mlynek·O. Biebel·R. Hertenberger·T. Nunnemann·D. Merkl·F. Rauscher·D. Schaile·R. Stroehmer
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Abstract

The influence of fast neutrons on the occupancy and the single tube resolution of ATLAS muon drift detectors was investigated by exposing a chamber built out of 3 layers of 3 short standard drift tubes to neutron flux-densities of up to 16 kHz/cm2 at a neutron energy of E=11 MeV. Pulse shape capable NE213 scintillaton detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured to be 4*10-4 by comparing data sets with and without neutron background. For the investigation of tracks of cosmic muons two silicon-strip detectors above and underneath the chamber allow to compare measured drift-radii with reference tracks. Alternatively, the single tube resolution was determined using the triple-sum method. The comparison between data with and without neutron irradiation shows only a marginal effect on the resolution and little influence on the muon track reconstruction.

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T. Mueller, A. Mlynek, O. Biebel, R. Hertenberger, T. Nunnemann, D. Merkl, F. Rauscher, D. Schaile, R. Stroehmer. 2009-08-11. ATLAS Monitored Drift Tube Chambers in E = 11 MeV Neutron Background. https://doi.org/10.1109/nssmic.2008.4774811

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