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arXiv · 2411.18346

First characterisation of the MAGO cavity, a superconducting RF detector for kHz-MHz gravitational waves

Lars Fischer·Bianca Giaccone·Ivan Gonin·Anna Grassellino·Wolfgang Hillert·Timergali Khabiboulline·Tom Krokotsch·Gudrid Moortgat-Pick·Andrea Muhs·Yuriy Orlov·Michel Paulsen·Krisztian Peters·Sam Posen·Oleg Pronitchev·Marc Wenskat
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Abstract

Heterodyne detection using microwave cavities is a promising method for detecting high-frequency gravitational waves or ultralight axion dark matter. In this work, we report on studies conducted on a spherical 2-cell cavity developed by the MAGO collaboration for high-frequency gravitational waves detection. Although fabricated around 20 years ago, the cavity had not been used since. Due to deviations from the nominal geometry, we conducted a mechanical survey and performed room-temperature plastic tuning. Measurements and simulations of the mechanical resonances and electromagnetic properties were carried out, as these are critical for estimating the cavity's gravitational wave coupling potential. Based on these results, we plan further studies in a cryogenic environment. The cavity characterisation does not only provide valuable experience for a planned physics run but also informs the future development of improved cavity designs.

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Lars Fischer, Bianca Giaccone, Ivan Gonin, Anna Grassellino, Wolfgang Hillert, Timergali Khabiboulline, Tom Krokotsch, Gudrid Moortgat-Pick, Andrea Muhs, Yuriy Orlov, Michel Paulsen, Krisztian Peters, Sam Posen, Oleg Pronitchev, Marc Wenskat. 2024-11-27. First characterisation of the MAGO cavity, a superconducting RF detector for kHz-MHz gravitational waves. https://doi.org/10.1088/1361-6382%2Fadd8da

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