Cart (Loading....) | Create Account
Close category search window
 

Mapping the large area straw detectors of the COMPASS experiment with X-rays

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

8 Author(s)
Platzer, K. ; Dept. of Phys., LMU Munich, Munchen, Germany ; Dunnweber, W. ; Dedek, N. ; Faessler, M.
more authors

In the COMPASS experiment at CERN, large straw drift tube detectors are used for large-angle tracking. To minimize the total areal density, a self supporting structure of thin-walled plastic tubes was chosen and, hence, a loss in mechanical precision was accepted. A complete mapping of the anode wire coordinate grid was required. An X-ray apparatus using a charge-coupled device (CCD) as imaging detector was built to investigate the mechanical properties and to calibrate (offline) the wire positions. Deviations of typically 200-400 μm from the nominal positions, defined by equal spacing, are found across the detector area of 8 m2. With a calibration method based on high-resolution CCD imaging and pattern recognition algorithms, the absolute wire coordinates are determined with an accuracy better than 30 μm across the whole detector area. Temperature effects are clearly seen. Their inhomogenity limits the achievable accuracy to about 50 μm under realistic experimental conditions, which is sufficient in view of the intrinsic straw resolution of 200 μm for minimum ionizing particles. The offline calibration was checked with particle tracks in the experimental setup, running COMPASS with 160 GeV/c muons. Tracks reconstructed with other detectors that cover a central angular range were used for this comparison. Good agreement is found between these in situ measurements and the X-ray calibration.

Published in:

Nuclear Science, IEEE Transactions on  (Volume:52 ,  Issue: 3 )

Date of Publication:

June 2005

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.