1. CAST-CAPP/IBS Detector Integration with the CAST Magnet Lino Miceli CAPP 2 Dec 2015

2. Agenda 2 Introduction: Lino Miceli Cavity cooling: A scheme proposed by Prof. Hyoungsoon Choi Discussion Vacuum vessel requirements and design Martyn Davenport: MRB 2K return pipe as a possible cooling source Discussion Outlook and planning

3. Meeting introduction 3 Main topics from last meeting: Requiring 1.8 K system temperature New vessel (“present concept”) Cavity cooling (including cables) Cooling power requirements Magnetic field shielding Establish the need for circulators A study to understand the consequences of a magnet quench and impact on cavity design.

4. 4 Cooling power requirements Main heat sources: amplifiers (inside the new vacuum vessel) and piezo actuators (inside the cold bore) Amplifiers: Low Noise Factory LNF-LNC4_8D Assuming factory DC power specification: 0.50 V @ 80 mA = 4 mW 14 cavities (filling one bore with 50 cm cavities) = 56 mW We should be safe if we plan for 500 mW Tuning piezo actuators: Janssen Precision Engineering CLA1801-HF Dissipation spec: 0.25 mJ / step @ 4 K. Assumed 1 mJ and 5 nm / step at a speed of 20 steps / s the cooling power requirement would be 20 mW. Moving 10 cavity simultaneously (no need to) the cooling power requirement inside the magnet is 200 mW

5. 5 Cooling power requirements (continued) Antenna (coupler) piezo actuators: Janssen Precision Engineering CLA1801-HF Assume similar figure as the tuning piezos Overall cooling power requirements for a magnet bore filled with 14, 50 cm long cavities 0.5 W inside the amplifier vacuum vessel 0.5 W inside the magnet bore Magnetic field shielding inside the vessel Maximum field requirement: 100 gauss