Search

Your search keyword '"Szczęśniak, T."' showing total 46 results
Start Over Author "Szczęśniak, T."
46 results on '"Szczęśniak, T."'

1. Cryogenic setup for the characterization of wavelength-shifting materials for noble element radiation detectors

Author

Choudhary, S., Cortez, A. F. V., Kuźniak, M., Nieradka, G., Sworobowicz, T., Świderski, Ł., and Szczęśniak, T.

Subjects
Physics - Instrumentation and Detectors
Abstract

In the present work, we describe a cryogenic setup for studies of wavelength-shifting materials for optimised light collection in noble element radiation detectors, and discuss the commissioning results. This SiPM-based setup uses alpha induced scintillation in gaseous argon as the vacuum ultraviolet light source with the goal of characterising materials, such as polyethylene naphthalate (PEN) and tetraphenyl butadiene (TPB), in terms of their wavelength-shifting efficiency. Further extensions of the system are currently being studied. The foreseen upgrades are expected to allow the study of GEM-like structures potentially interesting for rare-event searches. The design of the setup will be addressed along with the first results., Comment: LIDINE 2023, 7 pages, 4 figures, 1 table

Published
2024
Full Text
View/download PDF

2. Status and initial physics performance studies of the MPD experiment at NICA

Author

MPD Collaboration, Abgaryan, V., Kado, R. Acevedo, Afanasyev, S. V., Agakishiev, G. N., Alpatov, E., Altsybeev, G., Hernández, M. Alvarado, Andreeva, S. V., Andreeva, T. V., Andronov, E. V., Anfimov, N. V., Aparin, A. A., Astakhov, V. I., Atkin, E., Aushev, T., Averichev, G. S., Averyanov, A. V., Ayala, A., Babkin, V. A., Babutsidze, T., Balashov, I. A., Bancer, A., Barabanov, M. Yu., Baranov, D. A., Baranova, N., Barbashina, N., Baskakov, A. E., Batyuk, P. N., Bazhazhin, A. G., Baznat, D., Baznat, M., Bazylev, S. N., Beltran, L. G. E., Belyaev, A. V., Belyaev, S. E., Belyaeva, E. V., Benda, V., Bielewicz, M., Bietenholz, W., Blaschke, D., Blau, D., Bogdanova, G., Bogoslovsky, D. N., Boguslavsky, I. V., Boos, E., Botvina, A., Bravina, L., Bulychjov, S. A., Buryakov, M. G., Butenko, A. V., Butorin, A. V., Buzin, S. G., Bychkov, A., Bychkov, A. V., Cabellero, R. R., Arciniega, D. Chaires, Chalyshev, V. V., Chen, W., Chen, Z., Cheplakova, V. A., Chepurnov, V. F., Chepurnov, V. V., Cheremnova, M., Cheremukhina, G. A., Chlad, L., Chudoba, P., Chumakov, P. V., Cuautle, E., Czarnynoga, M., Dabrowska, B., Dąbrowski, D., Demanov, A., Dementyev, D. V., Deng, Z., Dmitriev, A. V., Dodokhov, V. Kh., Dolbilina, E. V., Dolbilov, A. G., Domínguez, I., Dominik, W., Donets, D. E., Dronik, V., Dubrovin, A. Yu., Dudziński, A., Dulov, P., Dunin, N. V., Dunin, V. B., Dyatlov, V., Dydyshko, V. F., Efremov, A. A., Egorov, D. S., Elsha, V. V., Emelyanov, A. E., Emelyanov, N. E., Ermakova, V. G., Eyyubova, G., Fang, D., Fateev, O. V., Fedin, O., Fedotov, Yu. I., Fedyunin, A. A., Feng, C., Feng, S., Feofilov, G. A., Filippov, I. A., Fischer, T., Formenko, K., Gaganova, M. A., Gandzhelashvili, T. T., Gavrishchuk, O. P., Geraksiev, N., Gerasimov, S. E., Gertsenberger, K. V., Golosov, O., Golovatyuk, V. M., Golubeva, M., Goncharov, I., Gorbunov, N. V., Grabowski, M., Grodzicka-Kobyłka, M., Grodzicki, K., Grzyb, J., Guber, F., Guirado, A., Guskov, A. V., Guzey, V., He, W., Rosas, L. A. Hernández, Huang, M., Huang, Y., Idczak, R., Idrisov, D., Igolkin, S. N., Ilieva, M., Isupov, A. Yu., Ivanishchev, D., Ivanov, A. V., Ivanytskyi, O., Ivashkin, A., Izvestnyy, A., Jaworska, E., Jiao, J., Kadochnikov, I., Kakurin, S. I., Kankiewicz, P., Kapishin, M. N., Karmanov, D., Karpushkin, N., Kartashova, L. A., Kashirin, E., Kasprowicz, G., Kasumov, Yu., Kechechyan, A. O., Kekelidze, G. D., Kekelidze, V. D., Khanzadeev, A., Kharlamov, P., Khilinova, O. A., Khodzhibagiyan, G. G., Khosravi, N., Khvorostukhin, A., Khyzhniak, Y., Kikvadze, V., Kireyeu, V. A., Kiryushin, Yu. T., Kiryutin, I. S., Kisiel, A., Klyuev, A., Klyukhin, V., Kochenda, L., Kodolova, O., Kolesnikov, V. I., Kolozhvari, A., Komarov, V. G., Kondratiev, V. P., Korolev, M., Korotkikh, V., Kotov, D., Kovalenko, S., Kovalenko, V. N., Kowalski, S., Kozlenko, N. A., Krakowiak, M., Kramarenko, V. A., Krasnova, L. M., Kravchov, P., Krechetov, Yu. F., Kruglova, I. V., Krylov, A. V., Krylov, V., Kryshen, E., Kryukov, A., Kubankin, A., Kugler, A., Kuich, M., Kukarnikov, S. I., Kuklin, S. N., Kukulin, V., Kuleshov, S., Kulikov, E. A., Kulikov, V. V., Kurepin, A., Kushpil, S., Kuzmin, V. S., Kvita, J., Lanskoy, D., Lashmanov, N. A., Ławryńczuk, M., Lazareva, T. V., Lednicky, R., Li, S., Li, Z., Litvinenko, A. G, Litvinenko, E. I., Litvinova, G. N., Liu, D., Liu, F., Livanov, A. N., Lobanov, V. I., Lobanov, Yu. Yu., Lobastov, S. P., Lokhtin, I., Lu, P., Lukstinsh, Yu. R., Luong, B. V., Łysakowski, B., Ma, Y., Machavariani, A., Madigozhin, D. T., Maksiak, B., Maksimenkova, V. I., Malakhov, A. I., Malayev, M., Maldonado, I., Maldonado, J. C., Malikov, I. V., Malinina, L., Maltsev, N. A., Maria, N. V., Shopova, M., Martemianov, M. A., Maslan, M., Matsyuk, M. A., Matulewicz, T., Melnikov, D. G., Merkin, M., Merts, S. P., Meshkov, I. N., Mianowski, S., Migulina, I. I., Mikhaylov, K. R., Milewicz-Zalewska, M., Minaev, Yu. I., Molokanova, N. A., Moreno-Barbosa, E., Morozov, S., Moshkin, A. A., Moshkovsky, I. V., Moskovsky, A. E., Movchan, S. A., Mudrokh, A. A., Mukhin, K. A., Murin, Yu. A., Musul'manbekov, Zh. Zh., Myalkovsky, V. V., Myktybekov, D., Paredes, L. L. Narvaez, Nauruzbaev, D. K., Nazarova, E. N., Nechaevsky, A. V., Nesterov, D. G., Nie, M., Nieto-Marín, P. A., Nigmatkulov, G., Nikitin, V. A., Nioradze, M., Niu, X., Nowak, W., Nozka, L., Oleks, I. A., Olshevsky, A. G., Orlov, O. E., Parfenov, P., Parzhitsky, S. S., Patiño, M. E., Pavlyukevich, V. A., Penkin, V. A., Peresedov, V. F., Peresunko, D., Peshekhonov, D. V., Petrov, V. A., Petrushanko, S., Petukhov, O., Piasecki, K., Pichugina, D. V., Piloyan, A., Pilyar, A. V., Piyadin, S. M., Plamowski, S., Platonova, M., Pluta, J., Potanina, A. E., Potrebenikov, Yu. K., Poźniak, K., Prokhorova, D. S., Prokofiev, N. A., Protoklitow, F., Prozorov, A., Pszczel, D., Puchkov, A. M, Pukhaeva, N., Puławski, S., Rakhmatullina, A. R., Herrera, L. F. Rebolledo, Reyna-Ortiz, V. Z., Riabov, V., Riabov, Yu., Ridinger, N. O., Rikhvitsky, V., Rodriguez-Cahuantzi, M., Rogachevsky, O. V., Rogov, V. Yu., Rokita, P., Romanenko, G., Romaniuk, R., Romanova, A., Rosłon, K., Rossler, T., Calderon, E. F. Rozas, Rufanov, I. A., Rumyantsev, M. M., Rustamov, A., Rybakov, A. A., Rybczyński, M., Rybka, D., Rymshina, A. A., Rzadkiewicz, J., Sadygov, Z. Ya. -O., Samsonov, V. A., Sandul, V. S., Sattarov, R., Savenkov, A. A., Schmidt, K., Seballos, S. S., Sedykh, S. A., Selyuzhenkov, I., Semchukova, T. V., Semenov, A. Yu., Semenova, I. A., Sergeev, S. V., Sergeeva, N. A., Serochkin, E. V., Seryakov, A. Yu., Shabunov, A. V., Shanidze, R., Shcheglova, L., Shchinov, B. G., Shen, C., Shen, Y., Sherbakov, A. N., Sheremetyev, A. D., Sheremetyeva, A. I., Shindin, R. A., Shipunov, A. V., Shitenkov, M. O., Shtejer, D. K., Shukla, U., Shunko, A. A., Shutov, A. V., Shutov, V. B., Sidorin, A. O., Skwira-Chalot, I., Slepnev, I. V., Slepnev, V. M., Slepov, I. P., Solnyshkin, Yu. A., Solomin, A., Solovyeva, T., Sorin, A. S., Starecki, T., Stefanek, G., Stepaniak, J., Streletskaya, E. A., Strikhanov, M., Strizh, T. A., Strizhak, A., Sukhov, N. V., Sukhovarov, S. I., Sun, X., Surkov, N. N., Suvarieva, D., Svalov, V. L., Świderski, L., Syntfeld-Każuch, A., Szcześniak, T., Szewiński, J., Tang, Z., Taranenko, A., Tarasov, N. A., Tcholakov, V., Tejeda-Muñoz, G., Tejeda-Yeomans, M. E., Terletskiy, A. V., Teryaev, O. V., Tikhomirov, V. V., Timoshenko, A. A., Tkachev, G. P., Toneev, V. D., Topilin, N. D., Traczyk, T., Tretyakova, T., Trubnikov, A. V., Trubnikov, G. V., Tyapkin, I. A., Udovenko, S. Yu., Poblete, P. A. Ulloa, Urbaniak, M., Urumov, V., Valenzuela-Cazares, L., Valiev, F. F., Vasendina, V. A., Vasiliev, I. N., Vasilyev, A., Vechernin, V. V., Vereshchagin, S. V., Vladimirova, N. N., Vlasov, N. V., Vodopyanov, A. S., Vokhmyanina, K., Volkov, V., Volodina, O. A., Voronin, A. A., Voronyuk, V., Wang, F., Wang, J., Wang, X., Wang, Y., Wieczorek, P., Wielanek, D., Włodarczyk, Z., Wójcik, K., Wu, K., Xiao, Z., Xu, Q., Yang, C., Yang, H., Yang, Q., Yarygin, G. A., Yordanova, L., Yu, T., Yuan, Z., Yurevich, V. I., Zabołotny, W., Zabrodin, E., Zaitseva, M. V., Saa, J. A. Zamora, Zamyatin, N. I., Zaporozhets, S. A., Zarochentsev, A. K., Zepeda-Fernández, C. H., Zha, W., Zhalov, M., Zhang, Y., Zhang, Z., Zhao, C., Zherebchevsky, V. I., Zhezher, V. N., Zhong, C., Zhou, W., Zhu, X., Zinchenko, A. I., and Zinchenko, D. A.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment, Nuclear Theory
Abstract

The Nuclotron-base Ion Collider fAcility (NICA) is under construction at the Joint Institute for Nuclear Research (JINR), with commissioning of the facility expected in late 2022. The Multi-Purpose Detector (MPD) has been designed to operate at NICA and its components are currently in production. The detector is expected to be ready for data taking with the first beams from NICA. This document provides an overview of the landscape of the investigation of the QCD phase diagram in the region of maximum baryonic density, where NICA and MPD will be able to provide significant and unique input. It also provides a detailed description of the MPD set-up, including its various subsystems as well as its support and computing infrastructures. Selected performance studies for particular physics measurements at MPD are presented and discussed in the context of existing data and theoretical expectations., Comment: 53 pages, 68 figures, submitted as a Review article to EPJA

Published
2022
Full Text
View/download PDF

4. Neutron hardness of EJ-276 scintillation material

Author

Mianowski, S., Brylew, K., Dziedzic, A., Grzenda, K., Karpowicz, P., Korgul, A., Krakowiak, M., Prokopowicz, R., Madejowski, G., Mianowska, Z., Moszynski, M., Szczesniak, T., and Ziemba, M.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract

This paper presents the results of the fast neutron irradiation (E$_n$ > 0.5MeV) of an EJ-276 scintillator performed in the MARIA research reactor with fluence up to 5.3$\times$10$^{15}$ particles/cm$^2$. In our work, four samples with size $\phi$25.4~mm$\times$5~mm were tested. The changes in the light yield, emission and absorption spectrum and neutron/gamma discrimination using PuBe source before and after irradiation are presented. The figure of merit in neutron/gamma discrimination based on the charge integration method for different neutron fluences and different short gate integration times are determined., Comment: 13 pages, 15 figures

Published
2020
Full Text
View/download PDF

5. SiPM proton irradiation for application in cosmic space

Author

Mianowski, S., Borowicz, D. M., Brylew, K., Dziedzic, A., Grodzicka-Kobylka, M., Korgul, A., Krakowiak, M., Mianowska, Z., Molokanov, A. G., Moszynski, M., Mytsin, G. V., Rybka, D., Shipulin, K., and Szczesniak, T.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

This paper presents the results of the proton irradiation of silicon photomulipliers (SiPMs) by mono-energetic 170 MeV protons with fluence up to 4.6$\times$10$^{9}$ particles/cm$^2$. In our work, three types of silicon photodetectors from Hamamatsu with areas 3$\times$3 mm$^2$ and different subpixel sizes of 25$\times$25 $\mu$m$^2$, 50$\times$50 $\mu$m$^2$, and 75$\times$75 $\mu$m$^2$ were used. The changes in the SiPM dark count rate (DCR) spectrum before and after irradiation in temperatures in the range of 20 $^\circ$C to -65 $^\circ$C are presented. The influence of the DCR changes on the energy resolution of the 662 keV gamma line from the $^{137}$Cs for a non-irradiated GAGG:Ce (1$\%$) scintillator is investigated. The time period of usability of the SiPM detector irradiated by protons in cosmic space was estimated.

Published
2020
Full Text
View/download PDF

26. Coincidence resolution time of two small scintillators coupled to high quantum-efficiency photomultipliers in a PET-like system

Author

Galetta G., De Leo R., Garibaldi F., Grodzicka M., Lagamba L., Loddo F., Masiello G., Nappi E., Perrino R., Ranieri A., and Szczęśniak T.

Subjects
Physics, QC1-999
Abstract

The lower limit of the time resolution for a positron emission tomography (PET) system has been measured for two scintillator types, LYSO:Ce and LuAG:Pr. Small dimension crystals and ultra bi-alkali phototubes have been used in order to increase the detected scintillation photons. Good timing resolutions of 118 ps and 223 ps FWHM have been obtained for two LYSO and two LuAG, respectively, exposed to a 22Na source.

Published
2014
Full Text
View/download PDF

37. Energy Resolution of Compton Electrons in LaBr3:Ce Scintillator.

Author

Swiderski, L., Moszyński, M., Czarnacki, W., Syntfeld-Każuch, A., Szczęśniak, T., Marcinkowski, R., Pausch, G., Plettner, C., and Roemer, K.

Subjects
FORCE & energy, COMPTON electrons, SCINTILLATORS, COMPTON effect, COLLISIONS (Nuclear physics)
Abstract

A method based on the Compton coincidence technique was applied to study the energy resolution of Compton electrons in wide energy range. The experimental setup was comprised of a High Purity Germanium (HPGe) detector and a LaBr3:Ce scintillator coupled to a photomultiplier. The detectors were set in a face-to-face geometry and the source was placed between them. Thus gating on events backscattered in the scintillator and detected in HPGe allowed one to measure the energy resolution of Compton scattered electrons at an energy corresponding to the Compton edge for a given source. This study confirms the importance of the electron scattering (δ-rays) as the main component of the intrinsic resolution in scintillators. The results are particularly important for discussion of the light yield non-proportionality contribution to the energy resolution of scintillators. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

38. Multi Pixel Photon Counters (MPPC) as an Alternative to APD in PET Applications.

Author

Nassalski, A., Moszyński, M., Syntfeld-Każuch, A., Szczęśniak, T., Świderski, Ł., Wolski, D., Batsch, T., and Baszak, J.

Subjects
PIXELS, PHOTONS, PHOTON detectors, DISODIUM pamidronate, POSITRON emission, POSITRON emission tomography
Abstract

The performance of multi pixel photon counters (MPPC) of 3 mm x 3 mm size, with 14400 and 3600 pixels, were studied by means of the signal from a laser light pulser and using the 3 mm x 3 mm x 20 mm LSO pixel scintillator. Special attention was paid to measure number of fired pixels, generated by the light of pulser and that of the LSO crystal, using a direct method of a comparison of the light peak position in the pulse height spectrum with that of the single photoelectron. The tests of the LSO crystal showed 1550 ± 80 fired pixels per MeV in the MPPC with 14400 pixels assuring a good linearity of the response up to about 1 MeV energy of gamma rays absorbed in the LSO crystal. Energy resolution of 14.8% for 662 keV gamma rays from 137Cs source and a time resolution of about 850 ps for 511 keV annihilation quanta were limited by a rather low number of the fired pixels compared to the number of photoelectrons in photomultipliers. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

39. A Time Resolution Study of a Continuous Crystal Detector for TOF PET.

Author

Szczęśniak, T., Moszyński, M., Świderski, Ł., Nassalski, A., Syntfeld-Każuch, A., Ojala, P., and Bohm, C.

Subjects
*POSITRON emission tomography, *PIXELS, *PHOTOMULTIPLIERS, *OPTICAL resolution, *PHOTOELECTRONS
Abstract

The majority of current Positron Emission Tomography (PET) systems are based on block-detectors consisting of many scintillating pixels read by a smaller number of photomultipliers (PMTs). An improvement of the time resolution, using a common light readout from a cluster of PMTs, was proposed by Kuhn et al., and tested by us earlier with LSO crystals. This, triggered an idea to design a new PET detector optimized for Time of Flight (TOF) systems, based on continuous crystals. In the present work, we report on optimization of timing with a 20 × 20 × 20 mm³ LYSO crystal coupled to a 16-channel photomultiplier H8711-200MOD from Hamamatsu. First, measurements were performed of the transit time jitter, the number of photoelectrons and the time resolution using a small 10 × 10 × 5 mm³ LSO crystal coupled to a H8711-200MOD PMT. Results were compared with data collected from fast timing photomultipliers like Photonis XP1020, XP3060, XP20D0 or Hamamatsu R9800. In the second part of the study, the time resolution measurements and the optimization of the system were made with a continuous LYSO crystal. The final results are discussed in terms of the measured photoelectron number and the requirements for the TOF-PET scanners. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

40. Further Study of Boron-10 Loaded Liquid Scintillators for Detection of Fast and Thermal Neutrons.

Author

Swiderski, L., Moszyński, M., Wolski, D., Batsch, T., Iwanowska, J., Nassalski, A., Syntfeld-Każuch, A., Szczęśniak, T., Kniest, Frans, Kusner, Michael R., Pausch, Guntram, Stein, J., Klamra, W., Schotanus, P., and Hurlbut, C.

Subjects
LIQUID scintillators, BORON compounds, THERMAL neutrons, BETA rays, FAST neutrons, NOISE measurement, PHOTOELECTRONS
Abstract

Boron-10 loaded liquid scintillators were studied in order to improve n/γ separation. Pulse shape discrimination (PSD) was implemented by means of a zero-crossing (ZC) method to distinguish between γ-rays and fast/slow neutrons. Significant progress was done for BC523A2 and EJ339A2 scintillators loaded with reduced amount of 10B (2% and 2.5%, respectively), as compared to the results obtained earlier with BC523A loaded with 4.4% of 10B. The improvement was probably caused by the reduction of 10B content, as indicated in the reported study. A 10B loaded scintillator EJ309B5 based on non-flammable liquid was also studied, showing the best separation of thermal neutron capture events from fast neutrons, γ-rays and noise. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

41. A Comparative Study of Undoped Nal Scintillators With Different Purity.

Author

Moszyński, M., Czarnacki, W., Syntfeld-Kažuch, A., Nassalski, A., Szczęśniak, T., Świderski, ł., Kniest, F., and Iltis, A.

Subjects
PARTICLES (Nuclear physics), DARK matter, IONIZING radiation, GAMMA rays, LIQUEFIED gases, INTERSTELLAR medium, ELECTROMAGNETIC waves, LIQUID nitrogen, CRYSTALLOGRAPHY
Abstract

The performance of undoped NaI crystal of a high purity of 7 N grade, developed by Saint-Gobain Crystals for a dark matter search, was studied at liquid nitrogen temperature using an avalanche photodiode. The measured quantities covered light output expressed in the electron-hole (e-h) pair number, non-proportionality characteristics, energy resolution and finally intrinsic resolution of the studied crystals. In contrast to the previous study, the new-crystals showed comparable non-proportionality curves to that known for NaI(Tl) at room temperature and a poor energy resolution of about 8% for 662 keV gamma rays from a 137Cs source. The performed study highlights a role of undoped NaI crystals in a better understanding of limitations of energy resolution in scintillation detectors. A high sensitivity to traces of doping may help to find the way of a modification of non-proportionality of other scintillators by a selective doping or co-doping. A further study of slow components of NaI light pulses and their influence on the energy resolution may clear up its possible deterioration caused by defects in the crystal structures [ABSTRACT FROM AUTHOR]

Published
2009
Full Text
View/download PDF

42. A Comparative Study of Silicon Drift Detectors With Photomultipliers, Avalanche Photodiodes and PIN Photodiodes in Gamma Spectrometry With LaBr3 Crystals.

Author

Moszyński, M., Plettner, C., Nassaiski, A., Szczęśniak, T., Świderski, Ł., Syntfeld-Każuch, A., Czarnacki, W., Pausch, G., Stein, J., Niculae, A., and Soltau, H.

Subjects
SILICON, GAMMA ray spectrometry, PHOTOMULTIPLIERS, GAMMA rays, PHOTODIODES, PHOTOELECTRONS, ELECTROMAGNETIC waves, IONIZING radiation, SPECTROMETRY
Abstract

The performance of a silicon drift detector (SDD) with an integrated FET, delivered by the company PNSensor, Munich, Germany, was studied in gamma spectrometry at room temper- ature (23-25°C) with a LaBr3 :Ce crystal of 6 mm diameter and 6 mm height. The SDD characteristics were compared with those measured with a Photonis XP5212 photomultiplier, a Large Area Avalanche Photodiode (LAAPD) of Advanced Photonix, Inc., and a Hamamatsu S3590-18 Photodiode (PD). Energy resolution versus gamma ray energies and its components related to the photoelectron/electron-hole pair statistics and dark noise were measured and compared. At low energies, below 100 keV, the light readout by the photomultiplier gives the best results, while for high energies, above 300 keV, the light readout by the SDD delivers superior energy resolution. In particular, the best energy resolution of 2.7% was determined for 662 keV gamma rays from a 137Cs source. [ABSTRACT FROM AUTHOR]

Published
2009
Full Text
View/download PDF

43. Application of Hamamatsu S8550 APD Array to the Common PET/CT Detector.

Author

Nassaiski, A., Moszyñski, M., Syntfe1d-Każuch, A., Świderski, Ł., Szczęśniak, T., Woiski, D., and Batsch, T.

Subjects
RADIOGRAPHY, MEDICAL radiography, X-ray densitometry in medicine, PHYSICS instruments, NUCLEAR medicine, TOMOGRAPHY, DETECTORS, RADIOGRAPHIC contrast media, CONTRAST media
Abstract

The progress of nuclear medicine and x-ray computer imaging encourage the researchers to develop new dual modality positron emission/X-rays tomography (PET/CT) systems, to acquire both the anatomical and the functional information during the same measurement, relying on the same detection system and electronics at the same time. The aim of this work was to study a detector consisting of four LSO pixel crystals coupled to a Hamamatsu S8550 avalanche photodiode (APD) array. The measurements covered tests of the detectors in the PET and in the CT modes using counting and current modes, respectively. The measurements included a determination of the light output, energy resolution, non-proportionality of the light yield and time resolution for 511 keV annihilation quanta, characterizing the PET detector, and the dependence of a counting rate versus a mean current of APD in the X-ray detection. [ABSTRACT FROM AUTHOR]

Published
2008
Full Text
View/download PDF

44. Study of LaBr 3 Crystals Coupled to Photomultipliers and Avalanche Photodiodes.

Author

Moszyński, M., Świderski, Ł., Szczęśniak, T., Nassalski, A., Syntfeld-Każuch, A., Czarnacki, W., Pausch, G., Stein, J., Lavoute, P., Lherbert, F., and Kniest, F.

Subjects
LANTHANUM, BROMINE, PHOTOMULTIPLIERS, METAL crystals, PHOTODIODES, PHOTOELECTRONS, GAMMA rays
Abstract

The performance of several BrilLanCe LaBr3 crystals that range in size from Oslash 6 times 6 mm2 up to Oslash 38 times 38 mm2 coupled to XP5212 and R6231MOD photomultipliers were studied, and in the case of the small crystals, the crystals were also coupled to large area avalanche photodiodes (LAAPD) of Advanced Photonix, Inc. First, the performance of several photomultipliers from Photonis and Hamamatsu with LaBr3 were compared to select the best one, not affecting energy resolution, besides the photoelectron statistics. The light output and energy resolution for 662 keV gamma rays from137 Cs source were measured for all crystals. Moreover, for some crystals, the non-proportionality of the light yield and energy resolution versus gamma ray energy were measured and the intrinsic resolution of the crystals was calculated. For the smallest crystals of Oslash 6 times 6 mm2 further comparative tests with LAAPD were carried out. [ABSTRACT FROM PUBLISHER]

Published
2008
Full Text
View/download PDF

45. Temperature dependences of LaBr3(Ce), LaCl3(Ce) and NaI(Tl) scintillators

Author

Moszyński, M., Nassalski, A., Syntfeld-Każuch, A., Szczęśniak, T., Czarnacki, W., Wolski, D., Pausch, G., and Stein, J.

Subjects
*LIGHT, *PULSE (Heart beat), *TEMPERATURE, *PHOTOELECTRONS
Abstract

Abstract: The temperature dependence of light output, energy resolution and decay time constants of the light pulses of NaI(Tl), LaCl3(Ce) (LaCl3) and LaBr3(Ce) (LaBr3) crystals were measured over the temperature range of −30 to 60°C. In the study of the light output, the number of photoelectrons produced by the scintillators in the XP2020 photomultiplier was measured and corrected for by the temperature dependence of the quantum efficiency determined for 360 and 420nm, respectively. It showed a high stability of the light output of LaBr3 of about 0.01%/°C and a comparable uniformity of LaCl3 at a long peaking time of 12μs. The well-known thermal instability of NaI(Tl) was confirmed at a short peaking time of 2μs. However, a much better stability of NaI(Tl) at low temperatures was observed for a long peaking time. The study of the decay of light pulses from LaCl3 and LaBr3 crystals confirmed earlier measurements, while NaI(Tl) showed a complex behavior at different temperatures. At low temperatures a strong contribution of a slow component of up to 60% of the total light was observed, while at elevated temperatures a well-known initial slow decay was replaced by a delayed maximum and the slow component became insignificant. The results of the study of energy resolution seem to be correlated with the variation of both the light output and a dependence of the decay time constants of the light pulses at changing temperature. This is particularly interesting in the case of NaI(Tl), where different dependencies of the energy resolution as a function of temperature for different peaking times in the spectroscopy amplifier were found. Tests of the XP2020 PMT itself showed that the thermal instability of the gain of the dynode structure of about−0.4%/°C is a dominating effect. The opposite effect on an increasing quantum efficiency, partly compensating for the gain instability, was observed above 10°C for the longer wavelength of 420nm. [Copyright &y& Elsevier]

Published
2006
Full Text
View/download PDF

46. Characterization of CaWO4 scintillator at room and liquid nitrogen temperatures

Author

Moszyński, M., Balcerzyk, M., Czarnacki, W., Nassalski, A., Szczęśniak, T., Kraus, H., Mikhailik, V.B., and Solskii, I.M.

Subjects
*LIQUID nitrogen, *LIQUEFIED gases, *SPECTROMETRY, *PHOTODIODES
Abstract

Abstract: The properties of CaWO4 (CaWO) crystals in γ-spectrometry were studied at room and liquid nitrogen(LN2) temperatures. Two small samples of 10×10×4mm3 and 10×10×8mm3 size were tested, coupled to a Photonis XP3212 photomultiplier at room temperature and a large area avalanche photodiode at LN2 temperature. Light pulse shape and light output at room and LN2 temperatures were measured. Energy resolution and non-proportionality of the CaWO response versus γ-ray energy were studied and compared with those of small BGO and CdWO4 crystals to discuss further the origin of the intrinsic resolution of undoped scintillating crystals. A high light output of 4800±200phe/MeV and a good energy resolution of 6.6±0.2% for 662keV γ-rays from a 137Cs source were measured for the small samples coupled to the XP3212 photomultiplier. [Copyright &y& Elsevier]

Published
2005
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results