In a conventional material, the coherent Cerenkov radiation due to a moving charged particle is associated with a velocity threshold, a forward-pointing radiation cone, and a forward direction of emission. We describe different behavior for the Cerenkov radiation in a photonic crystal. In particular, this radiation is intrinsically coupled with transition radiation and is observable without any...

Treatment of food with ionizing energy-'food irradiation'is finally becoming reality in many countries. The benefits include an improvement in food hygiene, spoilage reduction and extension of shelf-life. Although properly irradiated food is safe and wholesome, consumers should be able to make their own free choice between irradiated and non-irradiated food. For this purpese labelling is indisp...

We discuss whether the NuTeV anomaly can be explained, compatibly with all other data, by QCD effects (maybe, if the strange sea is asymmetric, or there is a tiny violation of isospin), new physics in propagators or couplings of the vector bosons (not really), loops of supersymmetric particles (no), dimension six operators (yes, for one specific SU(2)L-invariant operator), leptoquarks (not in a...

This report looks at the feasibility of detecting radiation sources by using the photons produced by the ionization of the air surrounding the source. Some of these fluorescence photons are emitted in the UV solar blind spectral region which offers the possibility of detection in full daylight. A review of the basic technique is given as well as detailed radiation source simulations using the G...

The Stanford Linear Accelerator Center (SLAC) operates a high energy (up to 33 GeV) linear accelerator delivering pulses up to a few microseconds wide. The pulsed nature of the electron beam creates problems in the detection and measurement of radiation both from the accelerator beam and the klystrons that provide the RF power for the accelerator. Hence, a pulsed x-ray facility has been built a...

Total reflection x-ray fluorescence (TXRF) using Synchrotron Radiation is likely to be the most powerful non-destructive technique for the analysis of trace metal impurities on silicon wafer surfaces. Of fundamental importance in TXRF is the achievable sensitivity as characterized by the minimum detection limit. This work describes the progress we achieved recently at the Stanford Synchrotron R...

Recently, there has been a significant interest in employing Terahertz (THz) technology, spectroscopy and imaging for standoff detection applications. There are three prime motivations for this interest: (a) THz radiation can detect concealed weapons since many non-metallic, non-polar materials are transparent to THz radiation, (b) target compounds such as explosives, and bio/chemical weapons h...