Speaker
Davide Pinci
(Universita e INFN, Roma I (IT))
Description
GEM-based detectors have had a noticeable development in last years and have successfully
been employed in different fields from High Energy Phisics to imaging applications.
Light production associated to the electron multiplication allows to perform an
optical readout of these devices. The big progress achieved in CMOS-based photosensors make possible to
develop a high sensitivity, high granularity and low noise readout.
In this work we present the results obtained by reading out the light produced by a triple-GEM structure
by means of a 4 mega-pixel CMOS sensor with a noise level lesser than 2 photons per pixel.
The choice of a CF$_4$ rich gas mixture (He/CF$_4$ 60/40) and a detailed optimization of the
electric fields allowed to reach a ligh-yield enough high to obtain, for the first time,
very visible signals of cosmic ray muons.
About 600 photons/mm were collected in average along the muon tracks and about 40 pixels/mm
gave a response three sigmas large than the pedestal.
Tracks due to electrons produced in natural radioactivity were also acquired and a light yield
10 times larger than cosmics was measured.
A test beam is foreseen for November 2015. More quantitative evaluations of the detector performance
(e. g. space resolution, tracking efficiency, light yield, energy released resolution) are expected.
These results will also be presented at the conference.
Primary author
Davide Pinci
(Universita e INFN, Roma I (IT))
Co-authors
Adalberto Sciubba
(Universita e INFN, Roma I (IT))
Alessio Sarti
(Universita e INFN, Roma I (IT))
Eleuterio Spiriti
(Istituto Nazionale Fisica Nucleare Frascati (IT))
Michela Marafini
(Unknown)
Vincenzo Patera
(Dipartim.di Fisica G.Marconi RomeI)
