Current Status of the ARRAKIHS Mission: UZH and Swiss Involvement in the Mission's Development

The ARRAKIHS mission, an ESA F-class mission scheduled for launch in the early 2030s, aims to revolutionize our understanding of dark matter and galactic structure formation. ARRAKIHS, standing for Analysis of Resolved Remnants of Accreted galaxies as a Key Instrument for Halo Surveys, is designed to image nearby galaxies similar to our Milky Way using four small telescopes observing in visible (VIS) and near-infrared (NIR) light. These observations will provide critical data on the abundance and distribution of dwarf galaxies, stellar streams, and intra-halo light, offering new insights into the ΛCDM model of cosmology and the nature of dark matter.

Switzerland plays a pivotal role in the ARRAKIHS mission through the development of the Thermal and Structural Subsystem (TSS), which is essential for maintaining the structural integrity and thermal stability of the payload. The Swiss coordinator for the mission is Prof. Ben Moore, and the presenter, Florian Kehl, serves as the Swiss Project Manager and Deputy Payload Manager on the European Consortium level. This seminar will provide an overview of the mission's objectives, focusing on the Swiss and UZH's contributions, including the design and optimization of the TSS. Key topics will include the challenges faced in ensuring the payload's mass remains within the tight constraints imposed by the small launcher, the development of advanced thermal management solutions to achieve cryogenic temperatures for the NIR detectors, and the structural analysis to ensure the optical bench's stability under operational conditions.

We recently achieved a critical milestone by successfully passing the Instrument Preliminary Requirements Review (iPRR), marking the end of Phase A and the beginning of Phase B of the payload development. This presentation will primarily focus on the technical aspects of the mission and the TSS, providing an update on our current status and the work ahead. The seminar will highlight the importance of the UZH and Swiss team's contributions to the success of the ARRAKIHS mission and the broader implications for cosmology and dark matter research.