background: total body irradiation (tbi) is different from standard radiotherapy in many aspects, so it is not easy to predict the delivered dose to the patient under tbi treatment. diode dosimetry procedures for surface dose reading can help to define variations of the actually delivered dose from the prescribed one. the aim of this study was to describe the measurements made to calibrate diod...

Background: Total Body Irradiation (TBI) is different from standard radiotherapy in many aspects, so it is not easy to predict the delivered dose to the patient under TBI treatment. Diode dosimetry procedures for surface dose reading can help to define variations of the actually delivered dose from the prescribed one. The aim of this study was to describe the measurements made to calib...

The forward voltage of GaAlAs semiconductor diode has been measured in the temperature range 50 K 300 K and for current values between 10 nA and 450 μA. The forward voltage as a function of temperature is least-squares fitted and the coefficients are given. The 1st and 2nd order least-squares fitting has high temperature root between 400 K and 950 K. The presence of the high temperature root in...

--The electrical International System of Units (SI) are defined and realized as DC electrical quantities. National Institute for Standards (NIS), Egypt maintains the DC voltage unit by using the DC Josephson Voltage Standard (JVS) as a primary standard for DC voltage adding to eight zener diode reference standards as DC voltage secondary standards. The JVS is used to provide traceability of ele...

The Global Precipitation Measurement (GPM) Microwave Imager (GMI) will fly on the GPM core spacecraft to be launched in 2013 and the low-inclination spacecraft to be launched in 2014 [1,2]. The GMI radiometer is a conically scanning microwave radiometer covering several bands from 10 to 183 GHz. The two primary on-board calibration targets are a warm load black-body and cold sky reflector. Addi...

We have developed calibration and data processing techniques optimized specifically for photon-integrating pixel array detectors (PADs). Primary effects to be calibrated are pixel gain variation and pixel area variation. Gain variations originate in pixel electronics and may be corrected for via a multiplicative factor. In contrast, area variations result from doping inhomogeneities in the sens...

Gas analyzers based on tunable diode-laser spectroscopy (TDLS) provide high sensitivity, fast response and highly specific in situ measurements of several atmospheric trace gases simultaneously. Under optimum conditions even a shot noise limited performance can be obtained. For field applications outside the laboratory practical limitations are important. At ambient mixing ratios below a few pa...

Interferometer mirror displacement induced by radiation pressure is used to demonstrate an alternative calibration method for the GEO 600 detector. The photon calibrator utilizes an amplitude modulated laser diode with up to 1.4 W output power at a wavelength of 1035 nm. The achieved accuracy of the strain amplitude calibration is dominated by the laser power calibration error, which is in the ...

Radiographic film dosimetry provides fast, convenient 2-D dose distributions, but is challenged by the dependence of film response on scatter conditions (i.e., energy dependence). Verification of delivered dose in the surface buildup region is important for intensity modulated radiation therapy (IMRT) when volumes of interest encroach on these regions (e.g., head/neck, breast). The current work...