ATLAS

Abstract:

New ZEUS data are added into the NLO QCD analysis of the ZEUS-JETS PDF fit. The addition of high-Q2 NC and CC e- p inclusive cross-section data improves the determination of the u-valence quark at high x. The addition of high-Q2 CC e+p inclusive cross-section data improves the determination of the d-valence quark at high x. The addition of lower-Q2 NC e+ p inclusive cross-section data, run at three difierent proton beam energies, improves the determination of the sea and gluon PDFs at small x. The new PDF fit is called the ZEUS09 PDF fit.

Abstract:

Deeply virtual Compton scattering, γ*p→γp has been measured in e+p collisions at HERA with the ZEUS detector using an integrated luminosity of 61.1 pb-1. Cross sections are presented as a function of the photon virtuality, Q2, and photon-proton centre-of-mass energy, W, for a wide region of the phase space, Q2 > 1.5GeV2 and 40 < W < 170GeV. A subsample of events in which the scattered proton is measured in the leading proton spectrometer, corresponding to an integrated luminosity of 31.3 pb-1, is used for the first direct measurement of the differential cross section as a function of t, where t is the square of the four-momentum transfer at the proton vertex. © SISSA 2009.

Abstract:

The cooling system of a large scale silicon detector system is critical for the long term operation of detectors in the harsh radiation environment of the LHC. The ATLAS and CMS experiments have developed and commissioned their large and complex distributed systems over the last few years. The systems are now complete and are in operation. In this publication I will describe the ATLAS and CMS systems and summarise some of the experience gained in the development and operation of these systems.

Abstract:

Direct measurements of the proton structure function FL have been performed in deep inelastic ep scattering at low x at HERA. The FL values are extracted by the H1 and ZEUS collaborations from the cross sections measured at fixed x and Q2 but different y values. This is achieved by using data sets collected with three different proton beam energies. The H1 and ZEUS results are consistent with each other and exhibit a non-zero FL. The measurements are also consistent with the previous indirect determinations of FL by H1. The results confirm DGLAP NLO and NNLO QCD predictions for FL(x,Q2), derived from previous HERA data, which are dominated by a large gluon density at low x.

Abstract:

EURECA (European Underground Rare Event Calorimeter Array) is an astro-particle physics facility aiming to directly detect galactic dark matter. The Laboratoire Souterrain de Modane has been selected as host laboratory. The EURECA collaboration unites CRESST, EDELWEISS and the Spanish-French experiment ROSEBUD, thus concentrating and focussing effort on cryogenic detector research in Europe into a single facility. EURECA will use a target mass of up to one ton, enough to explore WIMP - nucleon scalar scattering cross sections in the region of 10-9 - 10-10 picobarn. A major advantage of EURECA is the planned use of more than just one target material (multi target experiment for WIMP identification). © EAS, EDP Sciences 2009.