Terahertz spectroscopy has long been used as an important measurement tool in fields such as radio astronomy, physical chemistry, atmospheric studies and plasma research. More recently terahertz technology has been used to develop an exciting new technique to investigate the properties of a wide range of biological materials. Although much research remains before a full understanding of the int...

In this work we calibrated the NaI(Tl) scintillation detectors (5.08 × 5.08 cm and 7.62 × 7.62 cm) and the Full Energy Peak Efficiency (FEPE) for these detectors have been calculated for point sources placed at different positions on the detector axis using the analytical approach of the effective solid angle ratio. This approach is based on the direct mathematical method reported by Selim and ...

Integrating fixed and mobile roadway data 2 ABSTRACT Fixed-site and mobile data sources have distinct strengths for representing roadway conditions, and unique insights can be generated by combining the two. Ongoing research on an urban arterial roadway corridor combines distinct data sources for multi-criteria transportation facility performance assessment. The roadway is instrumented with an ...

In the beginning there was light. And it was good. Not long thereafter people began to look for a comprehensive understanding of its nature. While the publication record starts off a little spotty, in the fifth century BC the Greek philosopher Empedocles concluded that light consists of rays that emanate from the eye. This point of view was questioned using what today might be characterized as ...

We compare two geometries of sources and detectors for optimizing the diffuse optical imaging resolution of brain activation in humans. Because of limitations in the instruments' dynamic range, most diffuse optical brain activation images have used only nonoverlapping measurements. We demonstrate theoretically and with a human experiment that a simple geometry of sources and detectors can provi...

We review the current status of single-photon-source and single-photon-detector technologies operating at wavelengths from the ultraviolet to the infrared. We discuss applications of these technologies to quantum communication, a field currently driving much of the development of single-photon sources and detectors.

The data taken by the advanced LIGO and Virgo gravitational-wave detectors contains short duration noise transients that limit the significance of astrophysical detections and reduce the duty cycle of the instruments. As the advanced detectors are reaching sensitivity levels that allow for multiple detections of astrophysical gravitational-wave sources it is crucial to achieve a fast and accura...

A nonclassical light source is used to demonstrate experimentally the absolute efficiency calibration of a photon-number-resolving detector. The photon-pair detector calibration method developed by Klyshko for single-photon detectors is generalized to take advantage of the higher dynamic range and additional information provided by photon-number-resolving detectors. This enables the use of brig...