LC-ABD Work package 8, task 8.1, Laser based beam diagnostics

The laser-wire activities in Oxford aim at demonstrating that it is possible to measure the size of the ILC beams with a resolution of 1 micrometre or less by using a laser beam scanned accross the path of the electrons. To achieve such goals tests will be done at the Accelerator Test Facility (ATF) at KEK in Japan and at PETRA, DESY in Germany. As the ILC will need beam size measurements in several different locations, it is important to demonstrate that many laser-wire can be coordinated to work sequentially at the same facility. Such scheme will also be tested in Japan. At the ILC bunches of particles within a train will be spaced only by hundreds of nanoseconds but trains containing thousands of bunches will be spaced by almost two hundreds milliseconds. This makes the requirements on the laser very specific and no such laser exists to date but we plan to build one. This high power laser will also have to be more stable and reliable than what is currently available. Leading the effort to build a laser suitable for the ILC will also allow us to offer our expertise to ther groups that might need such lasers such as the group in charge of measurement the beam size at the focus point of the ATF-2. Finally, we will also try to understand how laser-wires can be integrated in the ILC design and how they can help the tuning of the accelerator.