Related papers: Optimization of the e-e- option for the ILC
Particle loss due to the emission of single energetic beamstrahlung photons in beam collisions is shown to impose a fundamental limit on storage-ring luminosities at energies greater than 2E~140 GeV for head-on collisions and 2E~40 GeV for…
The ILC baseline consists of two interaction regions, one with a 20mrad crossing angle and the other with a 2mrad crossing angle. It is known that the outgoing beam losses in the final doublet and subsequent extraction line are larger in…
For the $e^+ e^- \to e^+ e^- \gamma$ process at colliding beams, macroscopically large impact parameters give an essential contribution to the standard cross section. These impact parameters may be much larger than the transverse sizes of…
A novel method to measure the beam-beam interaction in e+e- colliders is presented.
Polarized lepton beams are an important aspect in the design of the future 100 km-scale Circular Electron-Positron Collider (CEPC). Precision beam energy calibration using resonant depolarization, as well as longitudinally polarized…
The role of the ILC final focus system (FFS) is to demagnify the beam to the sizes at the IP required to meet the ILC luminosity goals. The current design of final focus performs perfect chromaticity correction in both horizontal and…
In this paper we use current and proposed final doublet magnet technologies to reoptimise the interaction region of the International Linear Collider and reduce the power losses. The result is a set of three new final doublet layouts with…
For cross section measurements, an accurate knowledge of the integrated luminosity is required. The FCC-ee Z lineshape programme sets the ambitious precision goal of $10^{-4}$ on the \emph{absolute} luminosity measurement and one order of…
For contact-interaction searches at the Linear Collider, we discuss the advantages of polarizing both the electron and the positron beams as compared with polarizing only the electron beam. In particular, for the processes e^+e^-\to…
We have developed techniques that allow simultaneous measurement of the spatial size of the luminous colliding beam region and the angular spread of beams in collision using e+e- --> mu+mu- events. These are demonstrated at the CLEO…
We report the design status and beam dynamics challenges for the electron-positron branch of the Future Circular Collider (FCC) study, as of August 2015. After recalling motivation and physics requirements for the FCC-ee, we briefly discuss…
This note gives a conceptual description and illustration of the CLD detector, based on the work for a detector at CLIC. CLD is one of the detectors envisaged at a future 100 km $e^+e^-$ circular collider (FCC-ee). The note also contains a…
The physics potential of an e+e- linear collider can be significantly enhanced if both the electron and positron beams are polarised. Low energy running at the Z-resonance or close to the W-pair threshold is particularly attractive with…
For both the FCC-ee and the ILC, to exploit properly the respective precision physics program, the theoretical precision tag on the respective luminosity will need to be improved from the analogs of the $ 0.054 \% (0.061\%)$ results at LEP…
The International Linear Collider (ILC) is the next large scale project in accelerator particle physics. Colliding electrons with positrons at energies from 0.3 TeV up to about 1 TeV, the ILC is expected to provide the accuracy needed to…
The rapid increase of the e+e- --> W+W- cross section in the threshold region provides a method for measuring M(W) at LEP2. The dependence of the theoretical cross section -- including the effects of the finite W width, Coulomb interactions…
We discuss electron-electron contact-interaction searches in the process e^+e^- -->e^+e^- at a future e^+e^- Linear Collider with c.m. energy \sqrt{s}=0.5 TeV and with both beams longitudinally polarized. Our analysis is based on the…
The interaction of the two beams in a collider leads to a variety of effects that may limit the performance of the machine. This lecture introduces the basic aspects necessary to understand the design of modern colliders.
Linear collider designs are optimized for \ep\ collisions. However, from the physics point of view, \lc s may also be advantageously operated in an \ee, \eg\ or \pp\ mode. These options, which have not been available up to now, will provide…
To achieve the physics goals of future Linear Colliders, it is important that electron and positron beams are polarized. The positron source planned for the International Linear Collider (ILC) is based on a helical undulator system and can…