Data: Measurement of Darkness

arXiv (Cornell University)

Abstract

In experiments requiring extreme darkness, such as experiments probing the limits of human vision, assessment of the background photon flux is essential. However, direct measurement thereof with standard single photon detectors is challenged by dark counts and their fluctuations. Here we report an experiment and detailed statistical analysis of a direct measurement of darkness in a dedicated dark chamber suitable for human vision experiments, only using a standard single photon detector and a mechanical shutter. From a Bayesian analysis of $616$ h of data, we find substantial to decisive evidence for absolute darkness (depending on choice of prior distribution) based on the Savage-Dickey ratio, and a light level $<0.039$ cnt/s (posterior $0.95$-highest density interval).

Authors 2

1. Thomas H. A. van der Reep Aachen Leiden Institute of Physics (LION)

   Leiden University

   Affiliation as printed

   Leiden Institute of Physics , Niels Bohrweg 2 , 2333 CA Leiden , The Netherlands

2. Daniel Molenaar
   Affiliation as printed

   Psychology Research Institute , Nieuwe Achtergracht 129b , 1018 WS Amsterdam , The Netherlands