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Tl concentration and its variation in a CsI(Tl) crystal for the CALIFA detector

Knyazev, A. LU ; Park, J. LU ; Golubev, P. LU ; Pallon, J. LU ; Cederkall, J. LU ; Alvarez-Pol, H. ; Benlliure, J. ; Briz, J. A. ; Cabanelas, P. and Casarejos, E. , et al. (2020) In Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 975.
Abstract

One of the factors that can contribute to the resolution of long, doped inorganic scintillators used for nuclear spectroscopy is the variation of the dopant concentration over the length the detector crystal. In this work an investigation of such potential variations in one of the CsI(Tl) scintillators used in the calorimeter, CALIFA, of the R3B experiment at FAIR, has been performed using particle induced X-ray emission. No statistically significant gradient in doping level was found along the long axis of the investigated sample crystal and the mean value of the Tl concentration was measured to be 0.0839(38)% by weight. This corresponds to a light output of 97.3−1.7 +1.3% relative to the maximum... (More)

One of the factors that can contribute to the resolution of long, doped inorganic scintillators used for nuclear spectroscopy is the variation of the dopant concentration over the length the detector crystal. In this work an investigation of such potential variations in one of the CsI(Tl) scintillators used in the calorimeter, CALIFA, of the R3B experiment at FAIR, has been performed using particle induced X-ray emission. No statistically significant gradient in doping level was found along the long axis of the investigated sample crystal and the mean value of the Tl concentration was measured to be 0.0839(38)% by weight. This corresponds to a light output of 97.3−1.7 +1.3% relative to the maximum attainable light output according to previously published work. By taking the ±1σ bounds, the 3% statistical spread in the relative light output provides a good reference value of the minimum light-output non-uniformity observed for the CALIFA crystals. If the relative light output is estimated pointwise from a set of Tl concentration measurements a light-output non-uniformity of 4.6(2.4)% results. For a γ-ray energy of 662 keV the deduced variation in Tl concentration contributes with 0.48(6)% to the typical resolution of 7.74(6)% measured with a collimated source along the crystal main axis. The result is of interest for the characterization of the detector system performance and for realistic simulations of the light collection process in detector systems that are used for nuclear spectroscopy and calorimetry.

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organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Calorimeters, CsI(Tl) energy resolution, Nuclear reactions, Scintillators
in
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
volume
975
article number
164197
publisher
Elsevier
external identifiers
  • scopus:85085732806
ISSN
0168-9002
DOI
10.1016/j.nima.2020.164197
language
English
LU publication?
yes
id
014e655a-6b08-46e2-a614-77145c09c786
date added to LUP
2020-06-11 18:04:02
date last changed
2020-12-08 17:06:31
@article{014e655a-6b08-46e2-a614-77145c09c786,
  abstract     = {<p>One of the factors that can contribute to the resolution of long, doped inorganic scintillators used for nuclear spectroscopy is the variation of the dopant concentration over the length the detector crystal. In this work an investigation of such potential variations in one of the CsI(Tl) scintillators used in the calorimeter, CALIFA, of the R<sup>3</sup>B experiment at FAIR, has been performed using particle induced X-ray emission. No statistically significant gradient in doping level was found along the long axis of the investigated sample crystal and the mean value of the Tl concentration was measured to be 0.0839(38)% by weight. This corresponds to a light output of 97.3<sub>−1.7</sub> <sup>+1.3</sup>% relative to the maximum attainable light output according to previously published work. By taking the ±1σ bounds, the 3% statistical spread in the relative light output provides a good reference value of the minimum light-output non-uniformity observed for the CALIFA crystals. If the relative light output is estimated pointwise from a set of Tl concentration measurements a light-output non-uniformity of 4.6(2.4)% results. For a γ-ray energy of 662 keV the deduced variation in Tl concentration contributes with 0.48(6)% to the typical resolution of 7.74(6)% measured with a collimated source along the crystal main axis. The result is of interest for the characterization of the detector system performance and for realistic simulations of the light collection process in detector systems that are used for nuclear spectroscopy and calorimetry.</p>},
  author       = {Knyazev, A. and Park, J. and Golubev, P. and Pallon, J. and Cederkall, J. and Alvarez-Pol, H. and Benlliure, J. and Briz, J. A. and Cabanelas, P. and Casarejos, E. and Cortina-Gil, D. and Fernández, P. Díaz and Feijoo, M. and Galaviz, D. and Galiana, E. and Borge, M. J.G. and Gernhäuser, R. and Gonzalez, D. and Gutierrez-Neira, C. and Hartig, A. L. and Heinz, A. and Heiss, B. and Johansson, H. and Klenze, P. and Kröll, T. and Nilsson, T. and Perea, A. and Ponnath, L. and Rhee, H. B. and Rodriguez-Sanchez, J. L. and Tengblad, O. and Teubig, P.},
  issn         = {0168-9002},
  language     = {eng},
  month        = {09},
  publisher    = {Elsevier},
  series       = {Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment},
  title        = {Tl concentration and its variation in a CsI(Tl) crystal for the CALIFA detector},
  url          = {http://dx.doi.org/10.1016/j.nima.2020.164197},
  doi          = {10.1016/j.nima.2020.164197},
  volume       = {975},
  year         = {2020},
}