Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Localisation of gamma-ray interaction points in thick monolithic CeBr3
  and LaBr3:Ce scintillators   Localisation of gamma-ray interaction points in monolithic scintillator
crystals can simplify the design and improve the performance of a future
Compton telescope for gamma-ray astronomy. In this paper we compare the
position resolution of three monolithic scintillators: a 28x28x20 mm3 (length x
breadth x thickness) LaBr3:Ce crystal, a 25x25x20 mm3 CeBr3 crystal and a
25x25x10 mm3 CeBr3 crystal. Each crystal was encapsulated and coupled to an
array of 4x4 silicon photomultipliers through an optical window. The
measurements were conducted using 81 keV and 356 keV gamma-rays from a
collimated 133Ba source. The 3D position reconstruction of interaction points
was performed using artificial neural networks trained with experimental data.
Although the position resolution was significantly better for the thinner
crystal, the 20 mm thick CeBr3 crystal showed an acceptable resolution of about
5.4 mm FWHM for the x and y coordinates, and 7.8 mm FWHM for the z-coordinate
(crystal depth) at 356 keV. These values were obtained from the full position
scans of the crystal sides. The position resolution of the LaBr3:Ce crystal was
found to be considerably worse, presumably due to the highly diffusive optical
in- terface between the crystal and the optical window of the enclosure. The
energy resolution (FWHM) measured for 662 keV gamma-rays was 4.0% for LaBr3:Ce
and 5.5% for CeBr3. The same crystals equipped with a PMT (Hamamatsu R6322-100)
gave an energy resolution of 3.0% and 4.7%, respectively.

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The categories of this paper are: comp-gas
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The categories of this paper are: stat
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math