Enhancing the light yield of He:CF based gaseous detector

Area of Science:

• Particle Physics
• Astrophysics
• Experimental Physics

Background:

• The CYGNO experiment seeks to detect rare events like dark matter (DM) using a directional detector.
• The detector utilizes a time projection chamber (TPC) with a He:CF60/40 gas mixture and a Gas Electron Multiplier (GEM) amplification stage.
• Maximizing light yield from the amplification stage is crucial for lowering the experiment's energy threshold.

Purpose of the Study:

• To investigate the impact of an additional electric field on the GEM amplification stage's performance.
• To simulate and experimentally validate the effect of this electric field on light yield, energy resolution, and intrinsic diffusion.
• To optimize the detector's sensitivity for rare event searches, particularly for weakly interactive massive particles (WIMPs).

Main Methods:

• Simulations were performed to analyze the GEM field structure with an applied electric field below the last GEM plane.
• Experimental tests were conducted using a 10x10 cm prototype readout area.
• Measurements involved varying GEM stack configurations and helium concentrations in the gas mixture.

Main Results:

• The addition of a strong electric field significantly increased the light yield of the amplification stage.
• This enhancement was achieved without negatively impacting the intrinsic characteristics of the GEM amplification stage.
• Performance was evaluated in terms of light yield, energy resolution, and intrinsic diffusion.

Conclusions:

• The implemented electric field strategy effectively boosts light yield in the CYGNO detector's amplification stage.
• This method offers a promising avenue for improving the sensitivity of dark matter detectors.
• The findings support the development of advanced directional detectors for rare event searches.