Report of DM3 Workshop on September 15-17, 2022

Please enter the seminar report here!The study of dark matter (DM) has a long history. It starts in the 1930s from the article that Zwicky pointed out the existence of a huge invisible mass in galaxy clusters. We now know that about a quarter of the total energy density of the Universe is occupied by DM. But we still do not understand its nature, even we do not know whether or not it is a particle.

We have three kinds of strategies to probe DM so-called collider, direct detection, and indirect detection experiments. By establishing a smooth connection between each other with theoretical support, we should approach a better understanding of DM. With this rationale, the iTHEMS DM working group held an international workshop "DM3- Deep insights and Multiple strategies for Deciphering the Mystery of Dark Matter" during Sep.15-17. The theme of the workshop can be summarized as just a simple question, "what is DM for you?"

The workshop was composed of 18 invited talks for reviews of various DM studies and a poster session for individual presentations. The 1st day has been devoted to the discussion about DM search with astrophysical objects. On the 2nd day, we paid much attention to the particle nature of DM. Novel ideas for candidates and techniques to probe a huge parameter space of DM are exhibited. We went through the intersection between cosmic-ray study and DM search on the final day of the workshop. The latest status of the DM study was presented in posters.

Throughout the workshop, attendees discussed the nature and probe for DM regarding multiple aspects. According to the follow-up questionnaire, they said that "there are differences between the view before and after the workshop" and "would like to continue studying DM".

After the workshop, we reconsider the question again: "what is DM for you?"
There have been so many answers to the question till now. Continuing the study of DM, we believe that we see a consensus someday.

Reported by Nagisa Hiroshima