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In the last decade, many groups around the world have been exploring different ways to probe transport containers which may contain illicit Special Nuclear Materials such as uranium. The muon tomography technique has been proposed as a cost effective system with an acceptable accuracy. A group of Canadian institutions (see above), funded by Defence Research and Development Canada, is testing different technologies to track the cosmic muons. One candidate is the single wire Drift Chamber. With the capability of a 2D impact position measurement, two detectors will be placed above and two below the object to be probed. In order to achieve a good 3D image quality of the cargo content, a good angular resolution is required. The simulation showed that 1mrad was required implying the spatial resolution of the trackers must be in the range of 1 to 2 mm for 1 m separation. A tracking system using three prototypes has been built and tested. The spatial resolution obtained is 1.7 mm perpendicular to the wire and 3 mm along the wire. [ABSTRACT FROM AUTHOR]

AMADEUS is an experiment planned to be performed at the DAFNE e+e- collider of the Frascati National Laboratories (Italy) of INFN, to investigate the antikaon-nuclei interaction at low energies. AMADEUS will perform, for the first time, full-acceptance studies of antikaon interaction in light nuclei, including a complete experimental program for the case of the kaonic clusters. The study of the absorption of antikaon by the nucleus will provide information concerning the KN interaction and the modification of the kaon mass in the nuclear medium. The experiment is being preceded by the study of the hadronic interactions of K- in the 4He of the drift chamber from the KLOE experiment data. [ABSTRACT FROM AUTHOR]

Collimators are usually needed to image sources emitting X-rays that cannot be focused. Alternately, one may employ a Compton Camera (CC) and measure the direction of the incident X-ray by letting it interact with a thin solid, liquid or gaseous material (Tracker) and determine the scattering angle. With respect to collimated cameras, CCs allow higher gamma-ray efficiency in spite of lighter geometry, and may feature comparable spatial resolution. CCs are better when the X-ray energy is high and small setups are required. We review current applications of CCs to Gamma Ray Astronomy and Biomedical systems stressing advantages and drawbacks. As an example, we focus on a particular CC we are developing, which is designed to image small animals administered with marked pharmaceuticals, and assess the bio-distribution and targeting capability of these latter. This camera has to address some requirements: relatively high activity of the imaged objects; detection of gamma-rays of different energies that may range from 140 keV (Tc99m) to 511 keV; presence of gamma and beta radiation with energies up to 2 MeV in case of 188Re. The camera consists of a thin position-sensitive Silicon Drift Detector as Tracker, and a further downstream position-sensitive system employing scintillating crystals and a multi-anode photo-multiplier (Calorimeter). The choice of crystal, pixel size, and detector geometry has been driven by measurements and simulations with the tracking code GEANT4. Spatial resolution, efficiency and scope are discussed. [ABSTRACT FROM AUTHOR]

The GlueX experiment will search for exotic mesons produced by 9 GeV linearly polarized photons from the upgraded CEBAF machine. It is critical to detect and measure the four-momenta of all the charged particles and photons resulting from the decays of the mesons. The solenoid-based detector system includes tracking detectors and calorimeters. The Forward Drift Chamber, FDC, consists of 24 circular planar drift chambers of 1m diameter. Additional cathode readout is required to achieve efficient pattern recognition. The detection of photons by the electromagnetic calorimeters imposes constraints on the amount of material used in the FDC. The specific features of the detector and the readout electronics will be described. Results from the tests of the full scale prototype will be presented, as well. [ABSTRACT FROM AUTHOR]

We present the results of experimental study of the dynamics of plasma formations originated from the high-current multiwire X-pinch (the current value up to 2.3 MA) based on the wires of different thicknesses made of different materials [ABSTRACT FROM AUTHOR]

The purpose of this laboratory session is to provide the basic ingredients for understanding the construction and operation of Multiwire Proportional Chambers (MWPC). During this session the students constructed and tested a simple position sensitive MWPC. Only measurements requiring rather simple hardware (amplifiers, digital oscilloscope) were made and some of them are presented. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Drift chambers play an important role in particle physics experiments as tracking detectors. We started this laboratory course with a brief review of the theoretical background and then moved on to the the experimental setup which consisted of a single-sided, single-cell drift chamber. We also used a plastic scintillator paddle, standard P-10 gas mixture (90% Ar, 10% CH4) and a collimated 90Sr source. During the laboratory session the students performend measurements of the following quantities: a) drift velocities and their variations as function of the drift field; b) gas gains and c) diffusion of electrons as they drifted in the gas. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present recent results from KLOE on the dynamics of η → πππ decays, as well as searches for rare η decays, including a new determination of the η → π0γγ Branching Ratio. We also present a preliminary result on the ratio BR([lowercase_phi_synonym] → η′γ)/BR([lowercase_phi_synonym] → ηγ), a quantity related to the η - η′ mixing and the gluonium content of the η′. All results are obtained from the analysis of 450 pb-1 integrated luminosity from 2001–2002 runs. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Decays of the narrow Υ resonances have been studied with the CLEO-III detector. Among other things, inclusive photon spectra in Υ(2S) and Υ(3S) decays using a large statistics data sample have been obtained. The most precise measurements of electric dipole (E1) photon transition rates and photon energies for Υ(2S) → γχbJ(1P) and Υ(3S) → γχbJ(2P) (J = 0, 1, 2) are presented. The rare E1 transition Υ(3S) → γχb0(1P) has been measured for the first time. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]