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B. J. Holzer et al.
6.8.3 Proton-Proton Colliders
Proton-proton colliders require a dedicated magnet design with two separate vacuum chambers for the two equally charged beams. The first proton-proton collider
was the ISR (Intersecting Storage Rings) at CERN. It consisted of two rings of
943 m length which were intersecting at eight points. Out of these eight intersection
points six were used for experiments. The ISR was operated between 1970 and
1984. The top energy achieved for protons was 31.4 GeV/c. The ISR allowed not
only proton-proton collisions, but stored and collided later also deuterons, alpha
particles and antiprotons. The ISR pioneered a number of techniques which were
beneficial which paved the path for future high energy colliders like the SPS.
The proton-proton collider with the highest energy ever built is the Large Hadron
Collider (LHC) at CERN [70]. It uses superconducting magnets with two separate
vacuum chambers for the two equally charged beams. The design field is 8.36 T,
and the machine circumference 26.659 km which yields a design beam energy of
7 TeV. Higher field levels are being studied in the frame of possible further energy
upgrades.
A machine with an even higher beam energy of up to 50 TeV is presently being
studied by an international collaboration. The Future Circular Collider (FCC) has
a hadron-hadron option (FCC-hh) with a beam energy of 50 TeV [71]. The latest
design features a machine circumference of 97.75 km with a maximum dipole field
of 15.7 T. The size of the machine is a compromise of civil engineering constraints
and dipole feasibility.
6.8.4 Electron-Proton Colliders
Collisions between electrons and protons are used to study the inner structure
of the proton e.g. the quark gluon distribution underneath the valence quarks.
The electrons are used as a point like probe to determine the inner structures in
the target. This deep inelastic scattering studies were performed in the beginning
using an accelerated electron beam colliding on a fixed target. Due to kinematic
considerations however a much higher resolution is obtained if two accelerated
beams are brought into collision.
Due to the different nature and beam dynamics of the two particles an electronproton collider cannot be built as a single ring machine: It consists of two storage
rings of equal circumference, one being optimised for the acceleration and storage
of electrons, the other for a high energy proton beam. The design of these two rings
looks quite different and completely different effects determine the performance
limitations of the rings. Figure 6.30 shows the two storage rings of the HERA
collider:
HERA was built as a 6.3 km long double ring collider with beam energy
of 27.5 GeV for the electron beam, and 920 GeV for the proton beam [72].
The fundamental layout was based on four arcs and four straight sections where
B. J. Holzer et al.
6.8.3 Proton-Proton Colliders
Proton-proton colliders require a dedicated magnet design with two separate vacuum chambers for the two equally charged beams. The first proton-proton collider
was the ISR (Intersecting Storage Rings) at CERN. It consisted of two rings of
943 m length which were intersecting at eight points. Out of these eight intersection
points six were used for experiments. The ISR was operated between 1970 and
1984. The top energy achieved for protons was 31.4 GeV/c. The ISR allowed not
only proton-proton collisions, but stored and collided later also deuterons, alpha
particles and antiprotons. The ISR pioneered a number of techniques which were
beneficial which paved the path for future high energy colliders like the SPS.
The proton-proton collider with the highest energy ever built is the Large Hadron
Collider (LHC) at CERN [70]. It uses superconducting magnets with two separate
vacuum chambers for the two equally charged beams. The design field is 8.36 T,
and the machine circumference 26.659 km which yields a design beam energy of
7 TeV. Higher field levels are being studied in the frame of possible further energy
upgrades.
A machine with an even higher beam energy of up to 50 TeV is presently being
studied by an international collaboration. The Future Circular Collider (FCC) has
a hadron-hadron option (FCC-hh) with a beam energy of 50 TeV [71]. The latest
design features a machine circumference of 97.75 km with a maximum dipole field
of 15.7 T. The size of the machine is a compromise of civil engineering constraints
and dipole feasibility.
6.8.4 Electron-Proton Colliders
Collisions between electrons and protons are used to study the inner structure
of the proton e.g. the quark gluon distribution underneath the valence quarks.
The electrons are used as a point like probe to determine the inner structures in
the target. This deep inelastic scattering studies were performed in the beginning
using an accelerated electron beam colliding on a fixed target. Due to kinematic
considerations however a much higher resolution is obtained if two accelerated
beams are brought into collision.
Due to the different nature and beam dynamics of the two particles an electronproton collider cannot be built as a single ring machine: It consists of two storage
rings of equal circumference, one being optimised for the acceleration and storage
of electrons, the other for a high energy proton beam. The design of these two rings
looks quite different and completely different effects determine the performance
limitations of the rings. Figure 6.30 shows the two storage rings of the HERA
collider:
HERA was built as a 6.3 km long double ring collider with beam energy
of 27.5 GeV for the electron beam, and 920 GeV for the proton beam [72].
The fundamental layout was based on four arcs and four straight sections where