CAST microbulk micromegas in the Canfranc Underground Laboratory

Abstract

During the last taking data campaigns of the CAST experiment, the micromegas detectors have achieved background levels about 5 to 9 x10(-6)keV(-1)cm(-2)s(-1) between 2 and 9 keV. This performance has been possible thanks to the introduction of the microbulk technology, the implementation of a shielding and the development of discrimination algorithms. It has motivated new studies towards a deeper understanding of CAST detectors background. One of the working lines includes the construction of a replica of the set-up used in CAST by micromegas detectors and its installation in the Canfranc Underground Laboratory. Different contributions to the detectors background have been evaluated and an upper limit < 2 x 10(-7)keV(-1)cm(-2)s(-1) for the intrinsic background of the detector has been obtained. (C) 2012 Published by Elsevier B. V. Selection and/or peer review under responsibility of the organizing committee for TIPP 11.