Tipp 2014 - Third International Conference on Technology and Instrumentation in Particle Physics

Novel results on small gap Micromegas microbulks

Not scheduled

15m

Beurs van Berlage

Poster Sensors: 1c) Gaseous Detectors

Speaker

Dr Esther Ferrer Ribas (DAPNIA, Saclay)

Description

Small gap micromegas detectors ($< 50\,\rm\mu$m) are expected to be optimal for high pressure applications. These detectors are particularly relevant for rare event searches like double beta decay or dark matter search. We will present recent results obtained with small gap microbulks (25 and 12.5\,$\rm\mu$m) that have been manufactured recently. Electric field simulations taking into account the holes pattern will be also be exposed. The performance in terms of gain and energy resolution will be shown for different Argon-Isobutane mixtures and for different pressures. Energy resolutions as low as 12\% (FWHM) for the 12.5\,$\rm \mu$m while for the 25\,$\rm \mu$m values of 11.5\% have been reached at 5.9\,keV. These values are very close to the minimum energy resolution that can be achieved with gaseous detectors taking into account the fluctuations due to electron multiplication. The gain follows the expected bell shape with the maximum shifted with amplification gap: smaller gaps are more suitable for higher pressures. These tests confirm the suitability of small gap microbulk for rare event detection that would require operation pressures above the atmospheric.