Recent advances in electron and positron sources have resulted in new capabilities driven in most cases by the increasing demands of advanced accelerating systems. Electron sources for brighter beams and for high average-current beams are described. The status and remaining challenges for polarized electron beams are also discussed. For positron sources, recent activity in the development of po...

Positron annihilation on many molecules occurs via positron capture into vibrational Feshbach resonances, with annihilation rates often further enhanced by energy transfer to vibrational excitations weakly coupled to the positron continuum. Data presented here uncover another scenario in which the positron couples directly to a quasicontinuum of multimode vibrational states. A model that assume...

We have calculated electron and positron states in the Nd2_/ZexCuOq compound, for the perfect bulk lattice as well as when vacancy defects are included. We study the sensitivity of the results to different approximations in the positron potential. We also compute the annihilation rate and the electron-positron momentum density using the local density approximation and the newly developed gradie...

INTRODUCTION Fluorodeoxyglucose positron emission tomography scanning has an established role in the diagnostic work-up of many malignant diseases and also in the evaluation of cancer treatment response. Fluorodeoxyglucose positron emission tomography may, however be non-specific as infectious processes are depicted as well. CASE PRESENTATION We present a patient with longstanding leg pain an...

Positron annihilation spectroscopy in lifetime measuring mode exploring conventional fast-fast coincidence ORTEC system is employed to characterize free volume structure of commercially available acrylic-type dental restorative composite Charisma® (Heraeus Kulzer GmbH, Germany). The measured lifetime spectra for uncured and light-cured composites are reconstructed from unconstrained x3-term fit...

The design of the positron source for the Next Linear Collider (NLC) is presented. The key features of this design include accelerating positrons at an L-band frequency (1428 MHz) and using a rotating positron target with multi-stage differential pumping. Positron yield simulations show that the L-band design yields at the source 2.5 times the beam intensity required at the interaction point an...