Superfenic technology was first applied to Magnetic Resonance Imaging (MRI magnets by the Texas Accelerator Center cm magnet. In a evolutionary step, this technology is now being applied to the development of a whole body 4 Tesla / 1 meter magnet. The design of such a magnet is presented.

The basic design for the SSC started at Snowmass in the sumner of 1982. The premise is that a superferric SSC has the potential to be simple, reliable, inexpensive and provide future flexibility. A concentrated effort began in March of 1984 when the Texas Accelerator Center was formed.The TexasAccelerator Center is a group of about 50 people divided into three areas of research, a calculations group working on beam dynamics, an R and D group working on superconducting magnets, and an R and D group working on new accelerator ideas including a proton linac and a plasma-laser accelerator. This paper will emphasize the work on the superferric magnet R and D. Machine ParametersWe propose an injector system with a 3 GeV linac, a 3 to 100 GeV booster, and a 100 GeV to 2 Tev high energy booster. The main ring would cperate fran 2 TeV to 20 Tev. We are pursuing R and D for an if linac capable of 30 ma of beam with an emittance of lrmn.mr and high acceleration gradiant. The elements of this accelerator would be an Hf ion source, an RFQ, a 440mHz drift tube linac, and an undefined cavity structure.The first booster would have a 250 meter radius with small (6 "xll" ) 1.5 Tesla conventional magnets.This very small magnet with a 1'' aperture is allowed because of the small beam emittance. The small beam emittance is possible because the limit on beam emittance is normally at the injection of the linac into the first circular machi2ne3 This space charge blow up is proportional to y y and explains the reason for the 3 GeV linac. The booster would operate at 5 Hz and thus allow construction of a conventional beam tube for vaccum. Tis accelerator would be capable of acplerating 3x10 particles per bunch at 50 mHz or 3x10 per second.The high energy booster would use a unit of the superferric mgnet fran the big ring, which will be discussed below. This ring would have a radius of 2.5 kilcmeters, and would be an oval accelerator with straight sections on the two sides that could be used for machine functions or for interaction regions. The accelerator would be capable of a 1 minute cycle time similar to the Tevatron at Fermilab, and thus be able to load the large SSC ring in 10 minutes. It would be constructed with a 2-in-1 magnet so that beam could be simultaneously injected in each direction into the big ring.This would also permit colliding beam experiments in this ring at 2 Tev 3gn 22 _ The luminosity would be approximately 10 cm s . There would also be extracted beams for tests or fixed target physics.The main ring of the SSC would be rade up of 1330-115 meter units, plus straight sections for machine cperation and interaction regions, and have a total circumference of 162 kilcmeters. Each of the 115 meter units would be made up internally with 3-35 meter dipoles, 1-4.7 meter quadrApole, and 4.3 meters for a spool piece containing correction elements, position tronitors, expansion joints, and heat exchangers. The 35 m unit dipoles, quadrpoles, and spool pieces would be assembled individually at various industries throughout the c...

A high-field superferric accelerator dipole has been built and tested. The magnet was designed to operate at 7.6 Tesla. It achieved 6.5 Tesla with no training. The reduced performance is due to inadequate preload of the magnet during cooldown, and can be remedied by modification of the outer lining of the magnet.

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Strong, extensive magnetic fringe fields are a significant problem with magnetic resonance imaging magnets. This is particularly acute with 4-T, whole-body research magnets. To date this problem has been addressed by restricting an extensive zone around the unshielded magnet or by placing external unsaturated iron shielding around the magnet. This paper describes a solution to this problem which uses superconducting coils closely integrated with fully saturated iron elements. A 4-T, 30-cm-bore prototype, based on this design principle, was built and tested. The 5 G fringe field is contained within 1 meter of the magnet bore along the z axis. Homogeneity of the raw magnetic field is 10 ppm over 30% of the magnet's diameter after passive shimming. Compared with an unshielded magnet, 20% less superconductor is required to generate the magnetic field. Images and spectra are presented to demonstrate the magnet's viability for magnetic resonance imaging and spectroscopy.