Performance of the ultra wide bore 900 MHz NMR magnet at the national high magnetic field laboratory

A 900 MHz NMR magnet with a room temperature, clear bore of 105 mm was recently brought to full field at the NHMFL. The magnet was ramped to 21.1 T on its first run without incurring a quench, since installation into its final cryostat was completed. Issues on superconductor stability were present during magnet charging and are discussed. In addition, the magnet performance in terms of field uniformity and of field stability, with the implementation of a novel design concept of current injection, is presented.