Integration of Superconducting Tunnel Junctions in a Dry Adiabatic Demagnetization Refrigerator

Superconducting tunnel junction (STJ) detectors provide sub-keV energy resolution for direct spectroscopy of low-energy nuclear decays. Operating these detectors requires millikelvin temperatures, typically achieved with adiabatic demagnetization refrigerators (ADRs). Integrating STJs into such cryogenic systems introduces several practical challenges, including electronic noise, thermal coupling, and material expansion under repeated thermal cycling. We report on ongoing work toward the integration of STJs with an existing dry ADR system at the Colorado School of Mines, focusing on early-stage wiring design, magnetic shielding, and noise mitigation. Current efforts aim to establish stable thermal and electrical operation in preparation for detector characterization. These developments will support future deployment of superconducting sensors in cryogen-free environments for precision nuclear measurements and searches for physics beyond the Standard Model.