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A low background Micromegas detector for the CAST experiment

P. Abbon·S. Andriamonje·S. Aune·D. Besin·S. Cazaux·P. Contrepois·T. Dafni·T. Decker·N. Duportail·G. Fanourakis·E. Ferrer Ribas·T. Geralis·A. Giganon·I. Giomataris·M. Gros·R. Hill·I. G. Irastorza·K. Kousouris·J. Morales·M. Pivovaroff·M. Riallot·R. Soufli·K. Zachariadou·G. Zaffanela
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Abstract

A low background Micromegas detector has been operating on the CAST experiment at CERN for the search of solar axions during the first phase of the experiment (2002-2004). The detector operated efficiently and achieved a very low level of background rejection ($5\times 10^{-5}$ counts keV$^{-1}$cm$^{-2}$s$^{-1}$) thanks to its good spatial and energy resolution as well as the low radioactivity materials used in the construction of the detector. For the second phase of the experiment (2005-2007), the detector will be upgraded by adding a shielding and including focusing optics. These improvements should allow for a background rejection better than two orders of magnitude.

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P. Abbon, S. Andriamonje, S. Aune, D. Besin, S. Cazaux, P. Contrepois, T. Dafni, T. Decker, N. Duportail, G. Fanourakis, E. Ferrer Ribas, T. Geralis, A. Giganon, I. Giomataris, M. Gros, R. Hill, I. G. Irastorza, K. Kousouris, J. Morales, M. Pivovaroff, M. Riallot, R. Soufli, K. Zachariadou, G. Zaffanela. 2005-10-28. A low background Micromegas detector for the CAST experiment. https://doi.org/10.1142/9789812773678_0032

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