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Liquid xenon (LXe) is a very attractive material as a detection medium for ionization detectors due to its high density, high atomic number, and low energy required to produce electron-ion pairs. Therefore it has been used in several applications, like {\gamma} detection or direct detection of dark matter. Now Subatech is working on the R & D of LXe Compton telescope for 3{\gamma} medical imaging, which can make precise tridimensional localization of a ({\beta}+, {\gamma}) radioisotope emitter. The diffusion of charge carriers will directly affect the spatial resolution of LXe ionization signal. We will report how we measure the transverse diffusion coefficient for different electric field (0.5 ~ 1.2 kV/cm) by observing the spray of charge carriers on drift length varying until 12cm. With very-low-noise front-end electronics and complete Monte-Carlo simulation of the experiment, the values of transverse diffusion coefficient are measured precisely., Comment: 6 pages, 6 figures, proceeding of DSL-2011

The β autoradiography is commonly used in preclinical research. This technique is able to locate, in 2 dimensions with a high spatial resolution, molecule labeled with β emitters. We report on the development of an integrated and transportable device base on the PIM (Parallel Ionization Multiplier) structure able to perform the image of 10 microscope slides in the same time. Thin slices of organs can be labeled with β emitters of low energy like 3H / 14C or Auger electrons emitters such as 125I / 99mTc. The measured spatial resolution over the whole area of 18×18 cm² is 30μm Full Width at Half Maximum in 2D with a 3H labeling. The sensitivity threshold is estimated to be close to 0.005 cps/min/mm². The use in proportional counter mode is suitable to perform on-line imaging and monitoring. New modalities such as large area imaging of entire rat slices or imaging of β emitters of high energy like 131I or 18F are now under development. In case of labeling with β emitters of high energy, the spatial resolution is estimated to be around 200 μm. First results obtained with these new configurations will be presented.

We report on the development of a liquid-xenon time-projection chamber, designed to validate a new medical imaging concept named “3γ imaging”. The advantages of detection gamma-induced scintillation light with a gaseous photomultiplier (GPM) operating in cryogenic mode are discussed; first results are presented.

The ALICE muon spectrometer will be employed to measure the production of vector mesons in Pb-Pb collisions. In this paper we show some results concerning a test of an ALICE tracking chamber prototype. Performance such as resolution and efficiency as a function of high voltage are reported.

Operation results are presented of a UV-sensitive gaseous photomultiplier (GPM) coupled through a MgF2 window to a liquid-xenon scintillator. It consisted of a reflective CsI photocathode deposited on top of a THick Gaseous Electron Multiplier (THGEM); further multiplication stages were either a second THGEM or a Parallel Ionization Multiplier (PIM) followed by a MICROMEsh GAseous Structure (MICROMEGAS). The GPM operated in gas-flow mode with non-condensable gas mixtures. Gains of 10^4 were measured with a CsI-coated double-THGEM detector in Ne/CH4 (95:5), Ne/CF4 (95:5) and Ne/CH4/CF4 (90:5:5), with soft X-rays at 173 K. Scintillation signals induced by alpha particles in liquid xenon were measured here for the first time with a double-THGEM GPM in He/CH4 (92.5:7.5) and a triple-structure THGEM/PIM/MICROMEGAS GPM in Ne/CH4 (90:10) with a fast-current preamplifier., Comment: 12 pages, 9 figures, submitted to JINST

The Beta autoradiography is widely used in pharmacology or in biological fields to study the response of an organism to a certain kind of molecule. The image of the distribution is processed by studying the concentration of the radioactivity into different organs. We report on the development of an integrated apparatus based on a PIM device (Parallel Ionization Multiplier) able to process the image of 10 microscope slides at the same time over an area of 18*18 cm2. Thanks to a vacuum pump and a regulation gas circuit, 5 minutes is sufficient to begin an acquisition. All the electronics and the gas distribution are included in the structure leading to a transportable device. Special software has been developed to process data in real time with image visualization. Biological samples can be labelled with β emitters of low energy like 3H/14C or Auger electrons of 125I/99mTc. The measured spatial resolution is 30 μm in 3H and the trigger and the charge rate are constant over more than 6 days of acquisition showing good stability of the device. Moreover, collaboration with doctors and biologists of INSERM (National Institute for Medical Research in France) has started in order to demonstrate that MPGD's can be easily proposed outside a physics laboratory.

The ALICE Muon Spectrometer is mainly dedicated to the measurement of the production of the J//spl psi/, and Y families through their decay into muon pairs, in Pb-Pb collisions. In this paper we give a description of the dimuon tracking system, mainly concentrating on the modular CSC chambers which occupy the last three stations. The R&D phase is now almost over and the production of the final modules started. A description of the main performances of the detectors based on test beam results on prototypes will be given.