The National High Magnetic Field Laboratory has brought to field a Series-Connected Hybrid magnet for NMR spectroscopy. As a DC powered magnet it can be operated at fields up to 36.1 T. The series connection between a superconducting outsert and a resistive insert dramatically minimizes the high frequency fluctuations of the magnetic field typically observed in purely resistive magnets. Current-density-grading among various resistive coils was used for improved field homogeneity. The 48 mm magnet bore and 42 mm outer diameter of the probes leaves limited space for conventional shims and consequently a combination of resistive and ferromagnetic shims are used. Field maps corrected for field instabilities were obtained and shimming achieved better than 1 ppm homogeneity over a cylindrical volume of 1 cm diameter and height. The magnetic field is regulated within 0.2 ppm using an external 7Li lock sample doped with paramagnetic MnCl2. The improved field homogeneity and field regulation using a modified AVANCE NEO console enables NMR spectroscopy at 1H frequencies of 1.0, 1.2 and 1.5 GHz. NMR at 1.5 GHz reflects a 50% increase in field strength above the highest superconducting magnets available presently. Three NMR probes have been constructed each equipped with an external lock rf coil for field regulation. Initial NMR results obtained from the SCH magnet using these probes illustrate the very exciting potential of ultra-high magnetic fields.

A superconducting dipole, designed for use as a sweeper magnet in nuclear physics experiments, has been designed and built by the National High Magnetic Field Laboratory for operation at the National Superconducting Cyclotron Laboratory. The magnet operates at a peak field of 3.8 T in a 140 mm gap. A secondary beam enters the magnet from the upstream side before striking a target. The neutrons continue straight through to a neutron detector. The charged particles are swept 40 degrees on a one-meter radius into a particle spectrometer. To allow space for the exit of the downstream neutron beam, the magnet iron and coil structure are built in a modified "C" configuration. There are two coils of "D" shape, one above and one below the beam. This configuration keeps the magnet compact and removes the need for a negative curvature side. The peak field in the winding is 6.5 T. The net force on the curved leg of a single "D" is 1.6 MN. Results of system testing including cool-down, quench history, and integration with the cyclotron are presented.

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Abstract-Helmholtz-Zentrum Berlin operates two large scale facilities: the research reactor BER 2 and the synchrotron source for soft x-rays BESSY 2. This year HZB's neutron instrument suite around BER 2 has been strengthened by a unique high magnetic field facility for neutron scattering. Its main components are the High Field Magnet (HFM), the most powerful DC magnet for neutron scattering worldwide, and the Extreme Environment Diffractometer (EXED), the dedicated neutron instrument for time-of-flight technique. The hybrid magnet system is projected according to the special geometric constraints of analysing samples by neutron scattering in a high field magnet. Following our past experience only steady state fields are adequate to achieve the goals of the project. In particular inelastic scattering studies would virtually be excluded when using pulsed magnets. The new series-connected hybrid magnet with horizontal field orientation was designed and

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