Abstract
Abstract
Low pressure gaseous Time Projection Chambers (TPCs) are a
viable technology for directional Dark Matter (DM) searches and have
the potential for exploring the parameter space below the neutrino
fog [1,2]. Gases like CF4 are advantageous
because they contain flourine which is predicted to have heightened
elastic scattering rates with a possible Weakly Interacting Massive
Particle (WIMP) DM candidate [3,4,5]. The
low pressure of CF4 must be maintained, ideally lower than
100 Torr, in order to elongate potential Nuclear Recoil (NR) tracks
which allows for improved directional sensitivity and NR/Electron
Recoil (ER) discrimination [6]. Recent evidence suggests
that He can be added to heavier gases, like CF4, without
significantly affecting the length of 12C and 19F recoils
due to its lower mass. Such addition of He has the advantage of
improving sensitivity to lower mass
WIMPs [1]. Simulations can not reliably predict
operational stability in these low pressure gas mixtures and thus
must be demonstrated experimentally. In this paper we investigate
how the addition of He to low pressure CF4 affects the gas gain
and energy resolution achieved with a single Thick Gaseous Electron
Multiplier (ThGEM).