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Micropattern gaseous detectors (MPGD), especially Micromegas and GEM are
widely used by many experiments and future projects. The high radiation
resistance and excellent spatial and time resolution make them an
invaluable tool to confront future detector challenges at the next
generation of colliders.
Some examples are particle and nuclear physics projects: COMPASS, CAST,
LHC-B, TOTEM, STAR, NA48, CLAS12G, n-TOF, ILC, T2K, ATLAS-sLHC, CMS-sLHC.
I will present a fast review on principle and basic performance of
Micromegas detector. I will point out new developments that are
currently under way and especially novel industrial ways of fabricating
the detector in a single process.
High-accuracy TPC read-out detectors, with positive ion suppression
capability permitting to resolve high particle density events.
Originally developed for the high-energy physics, Micromegas
applications have expanded to astrophysics, neutrino physics, dark
matter search, neutron detection and medical imaging. Its ability to
detect low-energy, low-background rare events will also be discussed.
The detection of low energy ion recoils in dark matter search could be
of great importance to determine the direction of WIMP wind. First
reconstructed tracks of keV recoils will be presented as a proof of the
concept. The detector is used in CAST for solar axion search The
achieved low background level greatly improves the sensitivity of the
experiment and suggests future investigations.
A new type of radiation detector based on a spherical geometry will also
be presented. The detector consists of a large spherical gas volume with
a central electrode forming a radial electric field. A small spherical
sensor located at the center is acting as a proportional amplification
structure. This new concept has been proven to operate in a simple and
robust way and allows reading large volumes with a single read-out
channel. It allows high gas gains to be reached and operates in a wide
range of gas pressures. Sub-keV energy threshold with good energy
resolution is achieved. I will discuss recent results with a record
energy threshold of 20 eV. The bench mark result is the observation of a
well resolved peak at 283 eV due to carbon fluorescence which is unique
performance for such large-massive detector.
Such a device would open the way to detect the neutrino-nucleus
interaction, which, although a standard process, remains undetected due
to the low energy of the neutrino-induced nuclear recoils. Other physics
goals of such a device could include supernova detection, low energy
neutrino oscillations and study of non-standard properties of the
neutrino, among others.
Finally I will discuss two novel ideas in the neutrino physics sector:
- A background free neutrino less double beta decay experiment
- The direct detection of sterile neutrinos recently suggested by the
Reactor Neutrino Anomaly. |
