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Pulse height measurement is one of the most important step in ionizing radiation spectroscopy . However, the conventional analog and digital peak detection methods may be limited due to their high complexity and cost. In this work, a simple and novel mathematical approach based on Lagrange interpolation has been developed to precisely extract pulse height from a sequence of samples recorded at a low rate (2 MS/s). This has been implemented in an ARM-based micro-controller to construct a full functionality multi-channel analyzer. The results showed that the multi-channel analyzer has a very good integral linearity response (

To calibrate the energy response of the ATLAS liquid argon calorimeter, an electronics calibration board has been designed; it delivers a signal whose shape is close to the calorimeter ionization current signal with amplitude up to 100 mA in 50 Ω with 16 bit dynamic range. The amplitude of this signal is designed to be uniform over all calorimeters channels, stable in time and with an integral linearity much better that the electronics readout. The various R&D phases and most of the difficulties met are discussed and illustrated by many measurements. The custom design circuits are described and the layout of the ATLAS calibration board presented. The procedure used to qualify the boards is explained and the performance obtained illustrated: a dynamic range up to 3 TeV in three energy scales with an integral linearity better than 0.1% in each of them, a response uniformity better than 0.2% and a stability better than 0.1%. The performance of the board is well within the ATLAS requirements. Finally, in situ measurements done on the ATLAS calorimeter are shown to validate these performances.

We have developed a new position sensing method that can obtain position information directly from the pulse shape of a position-sensitive proportional counter (PSPC). A digital signal processing technique and a neural network algorithm have been used to recognize the pulse shapes and to obtain position information. The method has been applied to a one-sided read-out type PSPC where the pulse shapes depend strongly on the position of radiation interactions. The neural network can recognize the pulse shapes and provide the proper position even for positions that have not been taught in the learning process. The best relative position resolution is 6.4 × 10 −3 . Fairly good integral linearity has been obtained throughout the effective length of the PSPC.

Position-sensitive detectors are a vital research tool in many areas of structural and molecular biology and condensed matter physics. The present review is mainly restricted to structural information obtained by X-ray scattering and diffraction and in DNA sequence analysis using autoradiography. Film has traditionally played the most important role, and for many applications is still the best medium for recording data, but advances in various types of detector technology has made them attractive, and in some cases essential alternatives. The requirements imposed by experiments vary a great deal and can be very demanding in terms of detector performance, e.g. in terms of count rates, particularly for synchrotron radiation, dynamic range, spatial resolution, ability to do time-resolved measurements on a millisecond time scale, differential and integral linearity and resistance to radiation damage. A brief review of detector properties will be presented and how they are matched in different cases with the experimental requirements along with a small selection of recent results and what new developments are needed to cope with the new generation of storage rings now under construction.

We propose a novel position-sensing method using slow and fast components in an output signal observed at one end of a resistive anode wire in a proportional counter in which the other end of the anode wire was grounded through a capacitor. Fairly sufficient characteristics in position resolution and an integral linearity were obtained. This method will extend the application field of a position-sensitive detector.

A new type of two-dimensional neutron scintillation detector with high spatial resolution based on a position-sensitive photomultiplier has been investigated. With a 6Li glass scintillator a spatial resolution of 1.0 mm was measured. The integral linearity over the detection area of 55 × 45 mm2 is ⩽1.5 mm. The detector homogeneity is within 10% at a discriminator level at 60% of the average peak height. The spatial resolution is expressed by a geometrical parameter which could be evaluated from light experiments and by the number of photoelectrons per neutron capture.

This paper describes a new instrument that very accurately transforms the peak height of repetitive waveforms into a dc voltage. Used in conjunction with a precision pulse generator, this instrument provides an improved method for establishing the integral linearity of pulse amplifiers. A measured overall accuracy of 0.005% for pulses with a nominal 1.0 μs peaking time has been achieved. This method is particularly useful with very fast amplifiers in the 5–100 ns range. The results of linearity measurements on several typical amplifiers are presented.