arXiv subjects
Publications and source records attributed to T. Ohgaki.
We study a method of laser-Compton cooling of electron beams for future linear colliders. Using a Monte Carlo code, we evaluate the effects of the laser-electron interaction for transverse cooling. The optics with and without chromatic correction for the cooling are examined. The laser-Compton cooling for JLC/NLC at $E_0=2$ GeV is considered.
The Relativistic Electron Facility for Education and Research (REFER) at Hiroshima University accepts a 150 MeV electron beam from a microtron, the injector to the 700 MeV storage ring of the Hiroshima Synchrotron Research Center, and keep it circulating for 2.5ms without a RF acceleration. It acts as a beam stretcher and has been used for the following researches: 1) X-ray generation from an internal multiple foil crystalline target due to the parametric X-radiation (PXR) and the resonant transition radiation (RTR). 2) Laser backward Compton scattering. 3) Coherent pair creation from Si crystal by 150 MeV bremsstrahlung. 4) Study of the Ter-Mikaelian effect in the low energy part of the bremsstrahlung in an extracted electron line. 5) A novel scheme of beam stabilization by the induction coil. This paper reports the experimental results and the current status of the REFER electron ring.
We study a method of laser-Compton cooling of electron beams. Using a Monte Carlo code, we evaluate the effects of the laser-electron interaction for transverse cooling. The optics with and without chromatic correction for the cooling are examined. The laser-Compton cooling for JLC/NLC at E_0=2 GeV is considered.
We demonstrate a measurement of the Higgs boson mass by the method of energy scanning at photon-photon colliders, using the high energy edge of the photon spectrum. With an integrated luminosity of 50 $\rm{fb^{-1}}$ it is possible to measure the standard model Higgs mass to within 110 MeV in photon-photon collisions for m_h=100 GeV. As for the total width of the Higgs boson, the statistical error $ΔΓ_h/Γ_{h \rm{SM}}=0.06$ is expected for m_h=100 GeV, if both $Γ(h\toγγ)$ and $Γ(h\to b\bar{b})$ are fixed at the predicted standard model value.
The status and initial performance of a simulation program CAIN for interaction region of linear colliders is described. The program is developed to be applicable for e+e-, e-e-, e-gamma and gamma-gamma linear colliders. As an example of an application, simulation of a gamma-gamma collider option of NLC is reported.
Feasibility of a measurement of the partial decay width of the intermediate-mass Higgs boson into two photons at a photon-photon collider is studied by a simulation. The QCD radiative correction for quark pair background processes is taken into account for the realistic background estimation. It is found that the two-photon decay width can be measured with the statistical error of 7.6 % with about one year of experiment. The impact of the measurement of the two-photon decay width to look for the new physics beyond is demonstrated.