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13th International Conference on Accelerator and Large Experimental Physics Control Systems (ICALEPS 2011), Grenoble : France (2011)
A Combined On-Line Acoustic Flowmeter and Fluorocarbon Coolant Mixture Analyser for the ATLAS Silicon Tracker
R. Bates, M. Battistin, S. Berry, P. Bonneau, J. Botelho-Direito, B. DiGirolamo, J. Godlewski, E. Perez-Rodriguez, L. Zwalinski, N. Bousson1, G. Hallewell1, M. Mathieu1, A. Rozanov1, G. Boyd, M. Doubek, V. Vacek, M. Vitek, K. Egorov, S. Katunin, S. McMahon, K. Nagai
ATLAS Collaboration(s)
(2012)

An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) to a blend containing 10-30% of C2F6 (hexafluoro-ethane) to reduce the evaporation temperature and better protect the silicon from cumulative radiation damage with increasing LHC luminosity. Central to this upgrade is a new acoustic instrument for the real-time measurement of the C3F8/C2F6 mixture ratio and flow. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. The instrument has demonstrated a resolution of 3.10-3 for C3F8/C2F6 mixtures with ~20%C2F6, and flow resolution of 2% of full scale for mass flows up to 30gs-1. In mixtures of widely-differing molecular weight (mw), higher mixture precision is possible: a sensitivity of < 5.10-4 to leaks of C3F8 into the ATLAS pixel detector nitrogen envelope (mw difference 160) has been seen. The instrument has many potential applications, including the analysis of mixtures of hydrocarbons, vapours for semi-conductor manufacture and anaesthesia.
1 :  CPPM - Centre de Physique des Particules de Marseille
Physique/Physique/Physique des accélérateurs

Physique/Physique des Hautes Energies - Expérience

Physique/Physique Nucléaire Expérimentale
Lien vers le texte intégral : 
http://fr.arXiv.org/abs/1201.2640