Investigation of the Avalanche Fluctuations Factor in a Time Projection Chamber Detector Using 266 nm UV Laser

ime Projection Chambers (TPCs) are extensively used in collider experiments due to their superior physical performance. Particularly for future positron-electron colliders in Higgs physics studies, the next-generation TPC technology must provide better momentum resolution and improved spatial resolution. The avalanche fluctuation factor, a crucial parameter affecting spatial resolution, is challenging to measure accurately, whether directly or indirectly. This research leveraged the exceptional stability and ionization properties of ultraviolet lasers to achieve a precise determination of the avalanche fluctuation factor. The test outcomes were found to agree with the calculated values at the same gain levels, thereby validating the reliability of the experimental findings.