478
F. Bordry et al.
Fig. 8.83 Photograph of a collimating slit (LHC example) along the beam path. The collimator
tank hosts two 1.2 m long parallel jaws that define a collimating slit. The beam passes through
the middle. Collimator jaws, which are made of fiber-reinforced carbon (black material), intercept
stray particles. RF contacts guide electro-magnetic image currents. The jaw material is tapered at
its end to provide a smooth transition to the beam tank. More advanced designs implement orbit
pick-up bottoms in the tapered part to measure the beam position [242]
8.8.2.1 High Power Loads
State-of-the-art accelerators have advanced into the regime of high beam brightness.
This regime is characterized by high beam power that is compressed into small
transverse beam size. The beam power can be characterized by considering the
energy that is stored in one beam with N p charged particles:
E stored = pceN p .
(8.74)
Here, c is the light velocity. We consider particles with charge q = e and
relativistic momentum p. The stored energy in the beams is compared in Fig. 8.84
for several accelerator facilities. It is seen that modern accelerators operate or are
designed for beam momenta between a few GeV/c to a few TeV/c. The stored beam
energies are in the range of 10 KJ to 500 MJ. Losses and power loads must be
distinguished for different types of accelerators:
– The highest stored energies are achieved in proton storage rings (RHIC, Tevatron,
HERA, LHC) where the beam is kept for many hours [219, 220, 222, 233].
Power loss can be 1–500 kW if 0.1% of the beam is lost over 1 s. Several
future accelerators are under study and plan to exceed the design goal of the
LHC: the High-Luminosity upgrade of the LHC [236] is an approved project
that will increase by a factor 10 the LHC integrated luminosity starting in
2026 and HE-LHC [243] and FCC-hh [244] are studies for machines up to
50 TeV. Assuming similar loss scenarios for future accelerators, entails power
losses easily exceeding the MW levels. The loss will most often appear fully
F. Bordry et al.
Fig. 8.83 Photograph of a collimating slit (LHC example) along the beam path. The collimator
tank hosts two 1.2 m long parallel jaws that define a collimating slit. The beam passes through
the middle. Collimator jaws, which are made of fiber-reinforced carbon (black material), intercept
stray particles. RF contacts guide electro-magnetic image currents. The jaw material is tapered at
its end to provide a smooth transition to the beam tank. More advanced designs implement orbit
pick-up bottoms in the tapered part to measure the beam position [242]
8.8.2.1 High Power Loads
State-of-the-art accelerators have advanced into the regime of high beam brightness.
This regime is characterized by high beam power that is compressed into small
transverse beam size. The beam power can be characterized by considering the
energy that is stored in one beam with N p charged particles:
E stored = pceN p .
(8.74)
Here, c is the light velocity. We consider particles with charge q = e and
relativistic momentum p. The stored energy in the beams is compared in Fig. 8.84
for several accelerator facilities. It is seen that modern accelerators operate or are
designed for beam momenta between a few GeV/c to a few TeV/c. The stored beam
energies are in the range of 10 KJ to 500 MJ. Losses and power loads must be
distinguished for different types of accelerators:
– The highest stored energies are achieved in proton storage rings (RHIC, Tevatron,
HERA, LHC) where the beam is kept for many hours [219, 220, 222, 233].
Power loss can be 1–500 kW if 0.1% of the beam is lost over 1 s. Several
future accelerators are under study and plan to exceed the design goal of the
LHC: the High-Luminosity upgrade of the LHC [236] is an approved project
that will increase by a factor 10 the LHC integrated luminosity starting in
2026 and HE-LHC [243] and FCC-hh [244] are studies for machines up to
50 TeV. Assuming similar loss scenarios for future accelerators, entails power
losses easily exceeding the MW levels. The loss will most often appear fully