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arXiv · 2004.11499

Absolute measurement of the Fano factor using a Skipper-CCD

Dario Rodrigues·Kevin Andersson·Mariano Cababie·Andre Donadon·Ana Botti·Gustavo Cancelo·Juan Estrada·Guillermo Fernandez-Moroni·Ricardo Piegaia·Matias Senger·Miguel Sofo Haro·Leandro Stefanazzi·Javier Tiffenberg·Sho Uemura
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Abstract

Skipper-CCD can achieve deep sub-electron readout noise making possible the absolute determination of the exact number of ionized electrons in a large range, from 0 to above 1900 electrons. In this work we present a novel technique that exploits this unique capability to allow self-calibration and the ultimate determination of silicon properties. We performed an absolute measurement of the variance and the mean number of the charge distribution produced by $^{55}$Fe X-rays, getting a Fano factor absolute measurement in Si at 123K and 5.9 keV. A value of 0.119 $\pm$ 0.002 was found and the electron-hole pair creation energy was determined to be (3.749 $\pm$ 0.001) eV. This technology opens the opportunity for direct measurements of the Fano factor at low energies.

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Dario Rodrigues, Kevin Andersson, Mariano Cababie, Andre Donadon, Ana Botti, Gustavo Cancelo, Juan Estrada, Guillermo Fernandez-Moroni, Ricardo Piegaia, Matias Senger, Miguel Sofo Haro, Leandro Stefanazzi, Javier Tiffenberg, Sho Uemura. 2020-04-24. Absolute measurement of the Fano factor using a Skipper-CCD. https://doi.org/10.1016/j.nima.2021.165511

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