Novel approach to assess the impact of the Fano factor on the sensitivity of low-mass dark matter experiments

Understand

As first suggested by U.

• Fano in the 1940s, the statistical fluctuation of the number of pairs produced in an ionizing interaction is known to be sub-Poissonian.
• The dispersion is reduced by the so-called "Fano factor", which empirically encapsulates the correlations in the process of ionization.
• In modelling the energy response of an ionization measurement device, the effect of the Fano factor is commonly folded into the overall energy resolution.