At least three proposed future colliders (ILC, CLiC and LHeC) require a positron source with a yield greater than 10 e+s−1. An undulator-based positron source has the potential to provide the required yield. This design generates gamma rays by using a high energy electron beam traveling through a superconducting helical undulator. The gamma rays then pair produce in a titanium alloy target to p...

Pattern recognition and image recognition methods are commonly developed and tested using testbeds, which contain known responses to a query set. Until now, testbeds available for image analysis and content-based image retrieval (CBIR) have been scarce and small-scale. Here we present the one million images CEAList Image Collection (CLIC) testbed that we have produced, and report on our use of ...

In the framework of the CLIC (Compact Linear Collider) RF power source studies, the scheme of electron pulse compression and bunch frequency multiplication, using injection by RF deflectors into an isochronous ring, will be tested, at low charge, during the preliminary phase of the new CLIC Test Facility (CTF3) at CERN. In this paper, we describe the beam dynamics studies made in order to asses...

For the first time, production of a massive dark photon (DP) in $\gamma e^-$ scattering at future lepton colliders ILC, CLIC, and CEPC is examined. The invisible decay mode DP addressed. We have studied both unpolarized collision Compton backscattered photons with polarized electron. missing energy distributions are shown. considered wide range 10 GeV -- 1000 mass $m_{A'}$. excluded regions 95\...

beyond the standard model (SM) and SM backgrounds are carefully studied. We propose certain kinematic cuts to suppress the standard model backgrounds. For an integrated luminosity of 1 ab, we show that (a) γγ → ZZ can provide a test of gHγγ to the 3σ sensitivity of O(10 − 10) TeV at a 500 GeV ILC, and O(10) TeV at a 1 TeV ILC and a 3 TeV CLIC, and (b) γγ → WWWW at a 3 TeV CLIC can test all the ...

A new CLIC Test Facility (CTF3) at CERN will serve to study the drive beam generation for the Compact Linear Collider (CLIC). CTF3 has to accelerate a 3.5A electron beam in almost fully-loaded structures. The pulse contains more than 2000 bunches, one in every second RF bucket, and has a length of more than one μs. Different options for the lattice of the drive-beam accelerator are presented, b...

We review two commonly used approximate treatments of beamstrahlung at lepton colliders. We discuss the applicability of those approximations and show that they are bound to fail at very high energy ee colliders such as CLIC. We model the beamstrahlung effects at CLIC by an exact numerical solution to the evolution equation for beamstrahlung and compare to the two approximations. We also discus...