614
K. Hübner et al.
and the first observation of two-photon pair production. This collider was quickly
rebuilt as VEPP-2M.
10.3.3.5 ACO
ACO at Orsay was an early electron–positron collider used to demonstrate collider
principles [94]. This accelerator had six dipoles with quadrupoles in between. The
ring was later used as a synchrotron light source demonstrating ring based FEL
science. This accelerator gave way to the DCI collider a few years later.
10.3.3.6 ADONE
ADONE at Frascati was a one ring collider with a 50 MHz RF system [95].
ADONE had longitudinal phase feedback to damp beam instability modes, a 4 kG
detector solenoidal field (MEA), magnet shunts to adjust the beta functions in
the ring, and adjustable damping partition numbers generated by an RF frequency
change. Injection was from a linac with an energy ramp after the fill. The measured
luminosity increased a little over the fourth power of the energy. ADONE later
confirmed the existence of the J/Psi.
10.3.3.7 CEA
The CEA Cambridge Electron Colliding Beam Facility used a linac for injection
at 120 MeV (e + ) and 240 MeV (e − ) and then ramped both beams in the ring to
full energy [96]. The accelerator technology advancements for the CEA are the first
demonstration of a low beta insertion at the IP, single-turn pulsed orbit switching
into an interaction point (IP) magnetic bypass, switching from energy cycling to dc
operation at full energy and the addition of two damping magnets to redistribute
the radial damping so that both betatron and synchrotron oscillations were damped.
In particle physics the CEA measured that the R cross section ratio rose at higher
center of mass energy, hinting at many discoveries to come later at other colliders.
10.3.3.8 SPEAR
SPEAR at SLAC was designed as a two ring collider but due to funding only one
ring was built. Injection was at full energy from the SLAC 2-mile linac with a
positron source in linac sector 11 [97]. The ring lattice was extremely flexible in the
choice of operating tunes, dispersion, and beta values the IPs. Transverse horizontal
and vertical instabilities (head-tail) were observed at about 0.5 mA per bunch which
were cured by a positive chromaticity. The luminosity varied as the fourth power of
K. Hübner et al.
and the first observation of two-photon pair production. This collider was quickly
rebuilt as VEPP-2M.
10.3.3.5 ACO
ACO at Orsay was an early electron–positron collider used to demonstrate collider
principles [94]. This accelerator had six dipoles with quadrupoles in between. The
ring was later used as a synchrotron light source demonstrating ring based FEL
science. This accelerator gave way to the DCI collider a few years later.
10.3.3.6 ADONE
ADONE at Frascati was a one ring collider with a 50 MHz RF system [95].
ADONE had longitudinal phase feedback to damp beam instability modes, a 4 kG
detector solenoidal field (MEA), magnet shunts to adjust the beta functions in
the ring, and adjustable damping partition numbers generated by an RF frequency
change. Injection was from a linac with an energy ramp after the fill. The measured
luminosity increased a little over the fourth power of the energy. ADONE later
confirmed the existence of the J/Psi.
10.3.3.7 CEA
The CEA Cambridge Electron Colliding Beam Facility used a linac for injection
at 120 MeV (e + ) and 240 MeV (e − ) and then ramped both beams in the ring to
full energy [96]. The accelerator technology advancements for the CEA are the first
demonstration of a low beta insertion at the IP, single-turn pulsed orbit switching
into an interaction point (IP) magnetic bypass, switching from energy cycling to dc
operation at full energy and the addition of two damping magnets to redistribute
the radial damping so that both betatron and synchrotron oscillations were damped.
In particle physics the CEA measured that the R cross section ratio rose at higher
center of mass energy, hinting at many discoveries to come later at other colliders.
10.3.3.8 SPEAR
SPEAR at SLAC was designed as a two ring collider but due to funding only one
ring was built. Injection was at full energy from the SLAC 2-mile linac with a
positron source in linac sector 11 [97]. The ring lattice was extremely flexible in the
choice of operating tunes, dispersion, and beta values the IPs. Transverse horizontal
and vertical instabilities (head-tail) were observed at about 0.5 mA per bunch which
were cured by a positive chromaticity. The luminosity varied as the fourth power of