arXiv subjects
Publications and source records attributed to Toshiaki Tauchi.
In this brief overview we will reflect on the process of the design of the linear collider (LC) final focus (FF) optics, and will also describe the theoretical and experimental efforts on design and practical realisation of a prototype of the LC FF optics implemented in the ATF2 facility at KEK, Japan, presently being commissioned and operated.
The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.
The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.
We fabricated a readout ASIC with the fully depleted silicon-on-insulator (FD-SOI) technology for the pair-monitor. The pair-monitor is a silicon pixel device that measures the beam profile of the international linear collider. It utilizes the directional distribution of a large number of electron-positron pairs created by collision of bunches, and is required to tolerate radiation dose of about a few Mrad/year. The irradiation might cause the buried oxide layer of SOI to accumulate charges which interfere with intended functions. We thus performed extensive irradiation tests on the prototype ASIC, and the results are described in this paper.
A beam size monitor so called Shintake monitor, which uses the inverse Compton scattering between the laser interference fringe and the electron beam was designed for and installed at ATF2. The commissioning at ATF2 was started in the end of 2008 and succeeded in the measurement of the fringe pattern from the scattered gamma-rays. The present status of the Shintake monitor is described here.
At the International Linear Collider (ILC), measurement of the beam profile at the interaction point (IP) is a key issue to achieve high luminosity. We studied the beam size measurement by combination of Pair Monitor and BeamCal. We obtained measurement accuracies of 2.7%, and 6.6% for the horizontal, and vertical beam sizes, respectively, for 50 bunch crossings.
At the international linear collider, measurement of the beam profile at the interaction point is a key issue to achieve high luminosity. We report a simulation study on a new beam profile monitor, called the pair monitor, which uses the hit distribution of the electron-positron pairs generated at the interaction point. We obtained measurement accuracies of 5.1%, 10.0%, and 4.0% for the horizontal, vertical, and longitudinal beam size, respectively, for 50 bunch crossings.
The pair monitor is a beam profile monitor at interaction point (IP) for the international linear collider (ILC). We have designed and developed the pair monitor as a silicon pixel sensor which is located at about 400 cm from IP. As the first step to develop the pair monitor, the readout ASIC was developed. In this paper, test results of the readout ASIC and the future plan are reported.
We developed an electron beam size monitor for extremely small beam sizes. It uses a laser interference fringe for a scattering target with the electron beam. Our target performance is < 2 nm systematic error for 37 nm beam size and < 10% statistical error in a measurement using 90 electron bunches for 25 - 6000 nm beam size. A precise laser interference fringe control system using an active feedback function is incorporated to the monitor to achieve the target performance. We describe an overall design, implementations, and performance estimations of the monitor.
IP-BPM (Interaction Point Beam Position Monitor) is an ultra high resolution cavity BPM to be used at ATF2, a test facility for ILC final focus system. Control of beam position in 2 nm precision is required for ATF2. Beam tests at ATF extraction line proved a 8.7 nm position resolution.
At a warm linear collider the short time interval at which bunches will pass near each other in the interaction region may lead to significant alteration of the bunches positions. In this paper we quantify the intensity of this effect and show that it can be addressed by a fast intra-pulse feedback system.
At the Linear Collider mismatches between the two beams will result in an intense beamstrahlung. We have studied how this beamstrahlung would evolve as a function of the offset between the two beams and we suggest ways of monitoring it.