Μελέτη του φαινομένου της πραγματικής σύσμπτωσης σε ανιχνευτές γερμανίου με χρήση προσομοίωσης Monte-Carlo

Milioni, Anastasia; Μηλιώνη, Αναστασία

dc.contributor.author	Milioni, Anastasia	en
dc.contributor.author	Μηλιώνη, Αναστασία	el
dc.date.accessioned	2023-01-13T10:43:24Z
dc.date.available	2023-01-13T10:43:24Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/56697
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.24395
dc.rights	Default License
dc.subject	Πραγματική σύμπτωση	el
dc.subject	Gamma spectrometry	en
dc.subject	Germanium detectors	en
dc.subject	True coincidence	en
dc.subject	Ανιχνευτές Γερμανίου	el
dc.subject	Γ-φασματοσκοπία	el
dc.title	Μελέτη του φαινομένου της πραγματικής σύσμπτωσης σε ανιχνευτές γερμανίου με χρήση προσομοίωσης Monte-Carlo	el
heal.type	masterThesis
heal.classification	Applied Physics	el
heal.language	el
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2022-10
heal.abstract	An issue of outmost importance in gamma-ray spectrometry is the true coincidence phenomenon. It occurs in experiments involving cascade emitters, when two or more gamma rays (or a γ-ray and an X-ray) are emitted in cascade from an excited nucleus and they are detected “simultaneously”, namely within the resolution time of the gamma-ray detector. In this work, the true coincidence effect is studied for three Germanium (Ge) detector spectrometry systems and a variety of isotopes, source geometries and source to detector configurations, via computational tools based on Monte Carlo simulations. In particular, the upgraded patch of MCNP code MCNP-CP and the 2018 version of PENELOPE, which take into account the actual decay scheme of each cascade emitter nuclide, are used to calculate the Full Energy Peak Efficiency (FEPE) for the corresponding gamma-ray energies. The true coincidence correction (TCC) factors are calculated as the ratio of FEPE derived for each nuclide taking into consideration the true coincidence phenomenon, to the FEPE estimated neglecting the phenomenon. In all cases, a satisfactory agreement is observed between the TCC factors calculated using MCNP-CP and PENELOPE 2018. Furthermore, the computational results are validated against experimentally determined efficiency values. For this reason, the calculated via TrueCoinc software TCC factors are applied on the experimentally determined FEPE curves, based on measurements using reference sources. Finally, the corrected experimental curves are compared to the respective simulated ones for the “non-coincidence” case. The results of this work contribute to the validation of the computational tools and codes used to study the true coincidence effect and determine the corresponding correction factors, providing important data for gamma-spectrometry studies of cascade emitters.	el
heal.advisorName	Anagnostakis, Marios	el
heal.committeeMemberName	Vasilopoulou, Dora	en
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Εφαρμοσμένων Μαθηματικών και Φυσικών Επιστημών. Τομέας Φυσικής. Εργαστήριο Πυρηνικής Φυσικής και Εφαρμογών της	el
heal.academicPublisherID	ntua
heal.numberOfPages	122 σ.	el
heal.fullTextAvailability	false