10-16 June 2018
Dalhousie University
America/Halifax timezone
Welcome to the 2018 CAP Congress Program website! / Bienvenue au siteweb du programme du Congrès de l'ACP 2018!

A Novel Approach to Account for the Fano Factor (G)*

12 Jun 2018, 14:00
Dunn 135 (cap.82) (Dalhousie University)

Dunn 135 (cap.82)

Dalhousie University

Oral Competition (Graduate Student) / Compétition orale (Étudiant(e) du 2e ou 3e cycle) Particle Physics / Physique des particules (PPD) T3-3 Particle Physics IV (PPD) | Physique des particules IV (PPD)


Mr Daniel Durnford (Queen's University)


As first discussed by U. Fano in the 1940’s, the statistical fluctuation of the number of e-/ion pairs produced in an ionizing interaction is known to be sub-Poissonian, the dispersion being reduced by the so-called “Fano Factor”. Despite this knowledge, the Poisson distribution is commonly used to model the quantization of ionizing processes while the effect of the reduced dispersion is folded in with other processes affecting energy resolution. While this approximate treatment is valid down to relatively low energies, experiments now have energy thresholds low enough such that more accurate modeling on the order of a few pairs has become necessary.

We propose a new approach to this problem using a novel discrete probability distribution not well-known in the field of particle physics. The validity of this treatment is supported with calibration data obtained with a spherical proportional counter from the NEWS-G dark matter search experiment. As an application of this, the potential impact of the Fano Factor on sensitivity to low mass WIMPs is discussed as well.

Primary authors

Presentation Materials