### Abstract

The performance of scintillation detectors for X rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to study these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number of photoelectrons produced on the photocathode of the photomultiplier and for the underlying number of scintillation photons, can be deduced from these correlations. For LaBr_{3}(Ce) and 662 keV gamma rays, the photopeak signals obtained by photomultipliers on opposite faces of a thin sample are negatively correlated, and the Fano factor for the photoelectrons is significantly less than one. The inferred Fano factor for the optical photons is very small, indistinguishable from zero within experimental error.

Original language | English |
---|---|

Pages (from-to) | 359-362 |

Number of pages | 4 |

Journal | Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment |

Volume | 620 |

Issue number | 2-3 |

DOIs | |

Publication status | Published - 23 Apr 2010 |

Externally published | Yes |

### Fingerprint

### Keywords

- Fano factor
- Photoelectron anticorrelation
- Sub-Poisson statistics

### ASJC Scopus subject areas

- Instrumentation
- Nuclear and High Energy Physics

### Cite this

*Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment*,

*620*(2-3), 359-362. https://doi.org/10.1016/j.nima.2010.03.152

**Photoelectron anticorrelations and sub-Poisson statistics in scintillation detectors.** / Bousselham, Abdelkader; Barrett, Harrison H.; Bora, Vaibhav; Shah, Kanai.

Research output: Contribution to journal › Article

*Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment*, vol. 620, no. 2-3, pp. 359-362. https://doi.org/10.1016/j.nima.2010.03.152

}

TY - JOUR

T1 - Photoelectron anticorrelations and sub-Poisson statistics in scintillation detectors

AU - Bousselham, Abdelkader

AU - Barrett, Harrison H.

AU - Bora, Vaibhav

AU - Shah, Kanai

PY - 2010/4/23

Y1 - 2010/4/23

N2 - The performance of scintillation detectors for X rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to study these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number of photoelectrons produced on the photocathode of the photomultiplier and for the underlying number of scintillation photons, can be deduced from these correlations. For LaBr3(Ce) and 662 keV gamma rays, the photopeak signals obtained by photomultipliers on opposite faces of a thin sample are negatively correlated, and the Fano factor for the photoelectrons is significantly less than one. The inferred Fano factor for the optical photons is very small, indistinguishable from zero within experimental error.

AB - The performance of scintillation detectors for X rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to study these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number of photoelectrons produced on the photocathode of the photomultiplier and for the underlying number of scintillation photons, can be deduced from these correlations. For LaBr3(Ce) and 662 keV gamma rays, the photopeak signals obtained by photomultipliers on opposite faces of a thin sample are negatively correlated, and the Fano factor for the photoelectrons is significantly less than one. The inferred Fano factor for the optical photons is very small, indistinguishable from zero within experimental error.

KW - Fano factor

KW - Photoelectron anticorrelation

KW - Sub-Poisson statistics

UR - http://www.scopus.com/inward/record.url?scp=77955513182&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77955513182&partnerID=8YFLogxK

U2 - 10.1016/j.nima.2010.03.152

DO - 10.1016/j.nima.2010.03.152

M3 - Article

AN - SCOPUS:77955513182

VL - 620

SP - 359

EP - 362

JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

SN - 0168-9002

IS - 2-3

ER -