Brookhaven superconducting dipole magnet
date: label: Date made
content: 1974
name: label: manufacturer
content: Brookhaven National Laboratory
notes: label: Description
content: The Inner part of object 1988.0706.01 consists of a cylindrical metal bore tube surrounded on outer surface by insulation, covered by coil windings of braided niobium-titanium conducting wires held in place by white fiberglass-epoxy bands. This structure is surrounded by a yoke of octagonal cross-section, made of an upper and lower half consisting of vertical iron laminations. Surface coating (blueing?) of laminations is black and blue.
label: Description
content: About half of the length of the upper half of the yoke is removed to show the coil windings and bands. On both sides of the full-yoke segment are 18 nuts and Allen bolts for joining upper and lower yolk halves, and on both sides of half-yoke segment are 19 more holes without bolts along the cut-away portion.
label: Description
content: This object is the fourth in a series of eight one-meter long superconducting model dipoles constructed at Brookhaven National Laboratory (BNL). The coil aperture is 8 cm. Most of the design features incorporated in the full-scale 4.5 meter long dipoles for BNL's proposed ISABELLE proton-proton colliding beam facility were worked out on these shorter model magnets, including the superconducting coils. The conductor in the coil is in the form of a wide braid containing 93 twisted multi-filamentary niobium-titanium (NbTi) superconducting wires; each wire is 0.3 mm in diameter and contains 379 ten-micron NbTi filaments. The braid is filled with InPb for additional electrical stability and mechanical rigidity. The two coil halves are held on the bore tube by fiberglass-epoxy bands. The laminated shield, in addition to enhancing the magnetic field in the bore, maintains the coil structure under a predetermined compression at operating temperature. Mounted on the bore tube, immediately under the surrounding main coil windings, are barely discernable sextapole and decapole auxiliary windings in the form of 7-strand cables made from the same 0.3 mm composite wire; these coils primarily compensate for perturbations in the shape of the magnetic field due to iron saturation at high fields.
label: Description
content: For a detailed overview of the development of superconducting magnets for particle accelerators at BNL and Fermilab during the 1970's, see William D. Metz, SCIENCE, Vol. 200, 14 April 1978, pp 188-191. In particular, the BNL magnets have a significantly larger diameter relative to those at Fermilab. This is due to the fact that unlike the Fermilab magnets, whose surrounding steel yoke remains at room temperature, BNL chose to cool the entire magnet including the yoke to liquid helium temperature and have the central beam tube at room temperature ("warm bore, cold iron"), whereas the Fermilab beam tube is at cryogenic temperature ("cold bore, warm iron").
label: Description
content: For more on superconducting magnets in the Modern Physics Collection, see object ID no. 2012.0186.01, short section of parallel pair of Superconducting Super Collider (SSC) dipole magnets in their vacuum vessels (display model) [Web title "Sections of Magnets for Superconducting Super Collider"].
label: Location
content: Currently not on view
topic: label: general subject association
content: Science & Scientific Instruments
setName: label: See more items in
content: Medicine and Science: Modern Physics
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content: Energy & Power
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content: Science & Mathematics
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content: Modern Physics
creditLine: label: Credit Line
content: Brookhaven National Laboratory
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1988.0706.01
label: accession number
content: 1988.0706
label: catalog number
content: 1988.0706.01
objectType: label: Object Name
content: Dipole magnet, Superconducting
label: Object Name
content: solenoid, superconducting, brookhaven
label: Object Name
content: Superconducting Magnet
physicalDescription: label: Physical Description
content: metal; iron; niobium-titanium, fiberglass, epoxy (overall material)
label: Measurements
content: crated object:;
label: Measurements
content: overall (approx.): 50 cm x 50 cm x 100 cm; 19 11/16 in x 19 11/16 in x 39 3/8 in
label: Measurements
content: nbti strands: 10 mm; x 3/8 in
label: Measurements
content: nbti wires: .03 mm; x in
label: Measurements
content: crate: 20 3/4 in x 43 1/2 in x 19 in; 52.705 cm x 110.49 cm x 48.26 cm