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This paper presents options for high-energy colliders at the energy frontier for the years to come. The immediate plans include the exploitation of the LHC at its design luminosity and energy as well as upgrades to the LHC (luminosity and energy) and to its injectors. This may be complemented by a linear electron-positron collider, based on the technology being developed by the Compact Linear Collider and by the International Linear Collider, by a high-energy electron-proton machine, the LHeC, and/or by a muon collider. This contribution describes the various future directions, all of which have a unique value to add to experimental particle physics, and concludes by outlining the key messages for the way forward. [ABSTRACT FROM AUTHOR]

FLUKA Monte Carlo simulations have been performed to identify particle energy spectra and fluences relevant for evaluating the risk of single event effects in electronics installed in critical LHC underground areas. Since these simulations are associated with significant uncertainties, the results will compared with an online monitoring system installed to evaluate radiation levels at the location of the electronics. This comparison approach have been benchmarked in a mixed field reference facility and for a preliminary LHC monitoring case study. [ABSTRACT FROM AUTHOR]

Abstract: Jet cross sections have been measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The measurement uses an integrated luminosity of 17 nb−1 recorded at the Large Hadron Collider. The anti- algorithm is used to identify jets with a jet resolution parameter . The dominant uncertainty comes from the jet energy scale, which is determined to within 7% for central jets above 60 GeV transverse momentum. Inclusive single-jet differential cross sections are presented as functions of jet transverse momentum and rapidity. The results are compared to expectations based on next-to-leading-order QCD, which agree with the data, providing a validation of the theory in a new kinematic regime. [Copyright &y& Elsevier]

Abstract: The expected interaction rates at the LHC collider will exceed those of all previous particle physics experiments, which makes it mandatory to perform a very stringent online data selection (triggering). Event rates have to be reduced by factors of up to 107 without cutting signal events. The general-purpose experiments ATLAS and CMS pursue similar physics objectives with similar setups, while the dedicated b-physics experiment LHCb and the heavy-ion experiment ALICE have to use very specific triggering systems. [Copyright &y& Elsevier]

The ATLAS event monitoring service (Emon) is a CORBA-based peer-to-peer data distribution framework, which has been implemented for ATLAS - one of CERN's forthcoming particle physics experiments. Its purpose is to sample collision event data from various stages of the data flow chain and efficiently distribute them to the users. This paper discusses various technical details of the current peer-to-peer-based implementation. A special focus lies on dependability and the provision of scalability and predictable performance. A comparative study of message complexity and scalability as well as practical test results obtained during the HLT/DAQ large scale and performance test periods in July 2005 and November 2006 will be presented. Apart from that, a recent addition that facilitates the parallel analysis of event data on a set of machines will be presented. [ABSTRACT FROM PUBLISHER]

The CMS experiment at the LHC, CERN, will operate the largest tracker in the world entirely made of silicon detectors. The collaboration is facing the quality assurance work to prove the reliability and performance of the various parts produced by industry. A status report on the CMS Tracker is given, including the validation of single modules up to larger integrated substructures [ABSTRACT FROM PUBLISHER]

We present the results of a global irradiation test of full size triple-GEM detectors operated with a CF4-based gas mixture. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV gamma from a 60Co source. After the irradiation test the detectors' performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in the GEM detector during the strong irradiation [ABSTRACT FROM PUBLISHER]

We present recent results from charmonium and open charm production at the LHCb experiment at CERN, Geneva. We concentrate on studies for the measurement of the cross section pp → J/ψX in its decay channel with two muons, showing the agreement of the simulation with the data in few key distributions. We also show the reconstructed modes of D0 → K-π+, D0 → K-π+π0, $\Lambda _c^ + \, \to \,pK^ - \,\pi ^ + $ and $D^ + \, \to \,K_s^0 \pi ^ + $ and their prospects. [ABSTRACT FROM AUTHOR]

Abstract: ALICE [experiment web site, May 10, 2009 http://public.web.cern.ch/public/en/LHC/ALICEen.html ] (A Large Ion Collider Experiment) is an experiment at the LHC (Large Hadron Collider) optimized for the study of heavy-ion collisions. The main aim of the experiment is to study the behavior of strongly interaction matter and quark gluon plasma. The ALICE DAQ (Data Acquisition) system has been deployed and used intensively during the commissioning of the experiment. This paper will present the evolution of one particular area of the system: the detector readout. The data produced by each detector are received by DATE [ALICE data acquisition web site, May 10, 2009 http://phdepaid.web.cern.ch/phdepaid/ ] (ALICE Data Acquisition program) using PCI (Peripheral Component Interconnect) based card called D-RORC [web site, May 10, 2009 http://alice-proj-ddl.web.cern.ch/alice-proj-ddl/rorc_intro.html ] (DAQ Readout Receiver Card). Of the order of 400 of these cards are installed in the PCs of the DAQ farm, and they are connected by optical links called DDL [web site, May 10, 2009 http://alice-proj-ddl.web.cern.ch/alice-proj-ddl/ddl_intro.html ] (Detector Data Link) to the detector readout electronics. The D-RORC is controlled by the readout software, part of the DATE program that reads the events coming from these cards. We will present the results obtained during the performance tests of the new release of the D-RORC, PCI Express, in development at CERN. The paper will review the working principles of the D-RORC, its use by the readout software and the benefits in using PCI Express instead PCI-X. It will also introduce the work in progress for the new release of the readout software towards the next hardware platform based on 64-bit computer architecture and DDLs based on 10G Ethernet. [Copyright &y& Elsevier]