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CERN-ARCH CERN-ARCH-DIR-CERN-ARCH-DIR-ADM-01 · Series · 1952-1963
Part of CERN Directors of Administration

CERN-ARCH-DIR-ADM-01- sub-fonds covers the period between 1952 to 1975 Dakin, Samuel Arthur ffrench (1952 - 1955) Richemond, Jean Pierre (1955 - 1958) Dakin, Samuel Arthur ffrench (1958 - 1963) * Hampton, George Hughan (1963 – 1975)

Dakin, Samuel Arthur ffrench
Heritage collection CERN-OBJ-CERN-OBJ-AC-050 · Item
Part of Heritage Collection Test

About NbTi cable: The cable consists of 36 strands of superconducting wire, each strand has a diameter of 0.825 mm and houses 6300 superconducting filaments of niobium-titanium (Nb-Ti, a superconducting alloy). Each filament has a diameter of about 0.006 mm, i.e. 10 times smaller than a typical human hair. The filaments are embedded in a high-purity copper matrix. Copper is a normal conducting material. The filaments are in the superconductive state when the temperature is below about -263ºC (10.15 K). When the filaments leave the superconductive state, the copper acts as conductor transports the electrical current. Each strand of The NbTi cable (at superconducting state) has a current density of up to above 2000 A/mm2 at 9 T and -271ºC (2.15 K). A cable transport a current of about 13000 A at 10 T and -271ºC (2.15 K). About LHC superconducting wiring: The high magnetic fields needed for the LHC can only be reached using superconductors. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC will be the largest superconducting installation ever built and, at 1.9 degrees above absolute zero (300 degrees below room temperature), one of the the coldest objects in the universe! Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12 500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable to the weight of a jumbo jet. Coil winding requires great care to prevent movements as the field changes. Friction can create hot spots which “quench” the magnet and ruin its superconductivity. A quench in any of the LHC superconducting magnets would stop machine operation.

Heritage collection CERN-OBJ-CERN-OBJ-AC-051 · Item
Part of Heritage Collection Test

About NbTi cable: The cable consists of 36 strands of superconducting wire, each strand has a diameter of 0.825 mm and houses 6300 superconducting filaments of niobium-titanium (Nb-Ti, a superconducting alloy). Each filament has a diameter of about 0.006 mm, i.e. 10 times smaller than a typical human hair. The filaments are embedded in a high-purity copper matrix. Copper is a normal conducting material. The filaments are in the superconductive state when the temperature is below about -263ºC (10.15 K). When the filaments leave the superconductive state, the copper acts as conductor transports the electrical current. Each strand of The NbTi cable (at superconducting state) has a current density of up to above 2000 A/mm2 at 9 T and -271ºC (2.15 K). A cable transport a current of about 13000 A at 10 T and -271ºC (2.15 K). About LHC superconducting wiring: The high magnetic fields needed for the LHC can only be reached using superconductors. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC will be the largest superconducting installation ever built and, at 1.9 degrees above absolute zero (300 degrees below room temperature), one of the the coldest objects in the universe! Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12 500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable to the weight of a jumbo jet. Coil winding requires great care to prevent movements as the field changes. Friction can create hot spots which “quench” the magnet and ruin its superconductivity. A quench in any of the LHC superconducting magnets would stop machine operation.

Heritage collection CERN-OBJ-CERN-OBJ-AC-049 · Item
Part of Heritage Collection Test

The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12’500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable to the weight of a jumbo jet. Coil winding requires great care to prevent movements as the field changes. Friction can create hot spots which “quench” the magnet and ruin its superconductivity. A quench in any of the LHC superconducting magnets would stop machine operation. 50’000 tonnes of steel sheets are used to make the magnet yokes that keep the wiring firmly in place. The yokes constitute approximately 80% of the accelerator's weight and, placed side by side, stretch over 20 km!

Rundschreiben No. 6
CERN-ARCH-WP CERN-ARCH-PMC-CERN-ARCH-PMC-06-* CERN-ARCH-PMC-06-123 * 96349 · Item · 1951-04-10 - ?
Part of Pauli Manuscript Collection

Circular about the discussion for the 3rd Zurich talks (18 to 21 April 1951).Letter

Dialectica