Hit-time and hit-position reconstruction in strips of plastic scintillators using multi-threshold readouts
Abstract
In this article, a new method for the reconstruction of hit-position and hit-time of photons in long scintillator detectors is investigated. This research is motivated by the recent development of the positron emission tomography scanners based on plastic scintillators. The proposed method constitutes a new way of signal processing in Multi-Voltage-Technique. It is based on the determination of the degree of similarity between the registered signals and the synchronized model signals stored in a library. The library was established for a set of well defined hit-positions along the length of the scintillator. The Mahalanobis distance was used as a measure of similarity between the two compared signals. The method was validated on the experimental data measured using two-strips J-PET prototype with dimensions of 5x9x300 mm. The obtained Time-of-Flight (TOF) and spatial resolutions amount to 325~ps (FWHM) and 25~mm (FWHM), respectively. The TOF resolution was also compared to the results of an analogous study done using Linear Fitting method. The best TOF resolution was obtained with this method at four pre-defined threshold levels which was comparable to the resolution achieved from the Mahalanobis distance at two pre-defined threshold levels. Although the algorithm of Linear Fitting method is much simpler to apply than the Mahalanobis method, the application of the Mahalanobis distance requires a lower number of applied threshold levels and, hence, decreases the costs of electronics used in PET scanner.
Keywords
Cite
@article{arxiv.2004.12742,
title = {Hit-time and hit-position reconstruction in strips of plastic scintillators using multi-threshold readouts},
author = {N. G. Sharma and M. Silarski and J. Chhokar and E. Czerwinski and C. Curceanu and K. Dulski and K. Farbaniec and A. Gajos and R. Del Grande and M. Gorgol and B. C. Hiesmayr and B. Jasinska and K. Kacprzak and L. Kaplon and D. Kisielewska and K. Klimaszewski and G. Korcyl and P. Kowalski and N. Krawczyk and W. Krzemien and T. Kozik and E. Kubicz and M. Mohammed and Sz. Niedzwiecki and M. Palka and M. Pawlik-Niedzwiecka and L. Raczynski and J. Raj and S. Sharma and S. Shivani and R. Y. Shopa and M. Skurzok and W. Wislicki and B. Zgardzinska and P. Moskal},
journal= {arXiv preprint arXiv:2004.12742},
year = {2020}
}