Calibration and background data analysis in the scope of the NEWS-G dark matter experiment
dark matter , NEWS-G , spherical proportional counter , SPC , WIMP
The NEWS-G experiments aims at the discovery of low mass dark matter, using spherical proportional counters filled with gas. The latest detector, a 140-cm diameter copper sphere, has collected data in the Fall of 2019 at the Laboratoire souterrain de Modane (LSM) as a preparation for its future operation at SNOLAB starting in 2021. A paper from this data is in the final stages of preparation, and this thesis describes my work related to data analysis. More concretely, this thesis first explores the sphere conditions that affect the electron drift time. Then, it looks at the effect of alpha contamination and how the related background can be cut from the data. Finally, it shows how spike events can be identified and removed from the event selection.