Veronique Puill

Silicon PN photodiodes will be used in the light monitoring system of the electromagnetic calorimeter of CMS in order to calibrate the light injected onto each calorimeter channel. Since the calorimeter will undergo heavy radiation, we studied the behaviour of PN photodiodes under fast neutron irradiation performed at Saclay.

ABSTRACT The performance of a new Micromegas detection scheme was investigated. It consists of a gas amplification structure of Micromegas type with a stainless steel woven wire mesh instead of nickel etched grid. This mesh is produced in large dimensions and it is cheaper than grid produced by etching. It is easy to handle and can be cut up in various shapes including rounded contours. Micromegas needs narrow anode readout elements to achieve good spatial resolution and its use in a Time Projection Chamber would require too many electronic channels. We describe a new technique to improve spatial resolution while still using wide readout strips. The readout scheme consists of a resistive material several mm thick placed between the amplification gap and the anode. Its effect is to spread the induced signal over several millimeters.

ABSTRACT This work reports on Silicon Photomultipliers (SiPM) timing resolution measurements performed at the picosecond level at Laboratory of Linear Accelerator (LAL), In2p3- CNRS.The dependence of Single Photoelectron Timing Resolution (SPTR) with the applied voltage, wavelength of the light and the temperature was measured for detectors from Hamamatsu Photonics, AdvanSiD and Sensl with an active area of 1 and 9 mm2.The SPTR improves with the bias voltage increase. No significant variation of SPTR was observed with the temperature change. We also observed a weak variation of it as a function of the wavelength of the light. The best SPTR measured was about 120 ps (FWHM).

ABSTRACT This article reports on the design and features of a very compact and light gamma camera based on SiPM arrays and miniaturized readout electronics dedicated to tumor localization during radio-guided cancer surgery. This gamma camera, called MAGICS, is composed of four (2×2) photo-detection elementary modules coupled to an inorganic scintillator. The 256 channels photo-detection system covers a sensitive area of 54×53 m2. Each elementary module is based on four (2×2) SiPM monolithic arrays, each array consisting of 16 SiPM photo-sensors (4×4) with 3×3 mm2 sensitive area, coupled to a miniaturized readout electronics and a dedicated ASIC. The overall dimensions of the electronics fit the size of the detector, enabling to assemble side-by-side several elementary modules in a close-packed arrangement. The preliminary performances of the system are very encouraging, showing an energy resolution of 9.8% and a spatial resolution of less than 1 mm at 122 keV.

ABSTRACT In this Technical Design Report (TDR) we describe the SuperB detector that was to be installed on the SuperB e+e- high luminosity collider. The SuperB asymmetric collider, which was to be constructed on the Tor Vergata campus near the INFN Frascati National Laboratory, was designed to operate both at the Upsilon(4S) center-of-mass energy with a luminosity of 10^{36} cm^{-2}s^{-1} and at the tau/charm production threshold with a luminosity of 10^{35} cm^{-2}s^{-1}. This high luminosity, producing a data sample about a factor 100 larger than present B Factories, would allow investigation of new physics effects in rare decays, CP Violation and Lepton Flavour Violation. This document details the detector design presented in the Conceptual Design Report (CDR) in 2007. The R&D and engineering studies performed to arrive at the full detector design are described, and an updated cost estimate is presented. A combination of a more realistic cost estimates and the unavailability of funds due of the global economic climate led to a formal cancelation of the project on Nov 27, 2012.