The X-ray fluorescence technique is an important analytical tool for the non-destructive, simultaneous and multielemental analysis of samples with interest in various disciplines, from advanced materials, biomedicine, geology, to the environmental science and archaeometrical research. The Institute of Nuclear Physics of NCSR ‘Demokritos’ is equipped to produce X-rays from ions (using the TANDEM accelerator) or from electrons (using a variety of X-ray tubes of different power). The research in the field of X-ray spectroscopy includes studies in basic research as well as studies of multidisciplinary nature.
The CMS preshower detector is specifically designed to distinguish neutral pions (decaying in two photons) from Higgs photons. The main components of the detector are two active layers of silicon detectors in xy geometry in combination with two layers of Pb which forces photons in early conversion. The detectors is implemented in the form of circular annulus (two at each end cap of the experiment), covers a total area of 16m2 and comprises 5000 silicon sensors with dimensions 6.3cm x 6.3cm segmented in 32 strips. Demokritos is responsible for the construction and installation of 500 micromodules and is involved in physics studies concerning neutral pions reconstruction. Multivariable analysis methods (neural net, likelihood) are being used for pattern recognition. In parallel contributes to the development of other data reduction techniques within the trends of the CMS physics analysis program.
ΕΛΕΑ Data Acquisition, Monitoring and Analysis
The laboratory for Data Acquisition, Monitoring and Analysis (DAMA) was established in 1999 to support the needs of the Elementary Particle Physics groups of the Institute of Nuclear Physics on the methods and technology of Data Acquisition, Monitoring and Triggering systems as well as on the Statistical Data Analysis methodologies. Additionally DAMA specializes on the design and construction of detectors based on novel detector techniques. These detectors can be used in Elementary Particle experiments and in other applied fields as well as in Industry and Medical Physics.
Τhe Data Acquisition System for the Micromegas detector in the DAMA laboratory of the Institute of Nuclear Physics.
The DAMA lab also contributes to the formal education by introducing novel methods for the teaching of science (see Eudoxos) as well as novel teaching instrumentation
Data acquisition for X-ray imaging
The system comprises a linear array of CdTe sensors, a custom-made PCI card and two application specific integrated circuits (ASICs), a front-end readout chip and a digital counting chip. The dynamic range of the system is extended from 30keV up to 250keV. As the readout chip includes also a polarity select circuit, the system is suitable for applications with both types of detectors, that are electrons or holes collecting devices. Due to the adopted readout architecture the counting rate achieved is extremely high up to 3MHz. In the expense of that, the measured noise was around 1200 electrons for the 2pF detector capacitance