A. Faus-Golfe

Present status and first results of the final focus beam line at the KEK Accelerator Test Facility

ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U. S. scientists. The present status and first results are described.

Limits of chromaticity correction

The LHC luminosity upgrade supposes from the point of view of the optics the upgrade of the Interaction Regions (IR) of the main experiments ATLAS and CMS. This upgrade is expected to provide a of 25 cm instead of the 50 cm of the nominal one. This decreasing in implies an increasing of the maximum in the lowquadrupoles and subsequently a more difficult chromaticity correction. In this report we analyze ithe limits and possible strategies on the chromaticity correction for the different optics proposed for the upgrade of the IR.