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First tests of a Micromegas TPC in a magnetic field

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 نشر من قبل Francoise Marechal
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English
 تأليف P. Colas




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Since the summer of 2003, a large Micromegas TPC prototype (1000 channels, 50 cm drift, 50 cm diameter) has been operated in a 2T superconducting magnet at Saclay. A description of this apparatus and first results from cosmic ray tests are presented. Additional measurements using simpler detectors with a laser source, an X-ray gun and radio-active sources are discussed. Drift velocity and gain measurements, electron attachment and aging studies for a Micromegas TPC are presented. In particular, using simulations and measurements, it is shown that an $Argon-CF_4$ mixture is optimal for operation at a future Linear Collider.



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