Combination and summary of ATLAS dark matter searches within 2HDM+a framework

In the 1930s, Swiss astronomer Fritz Zwicky observed that the velocities of galaxies in the Coma Cluster were too high to be maintained solely by the gravitational pull of luminous matter. He proposed the existence of some non-luminous matter within the galaxy cluster, which he called dark matter. This discovery marked the beginning of humanity's understanding and study of dark matter.