The measurement of missing transverse momentum in the ATLAS detector, described in this paper, makes use of the full event reconstruction and a calibration based on reconstructed physics objects. The performance of the missing transverse momentum reconstruction is evaluated using data collected in pp collisions at a centre-of-mass energy of 7 TeV in 2010. Minimum bias events and events with jets of hadrons are used from data samples corresponding to an integrated luminosity of about 0.3 nb −1 and 600 nb −1 respectively, together with events containing a Z boson decaying to two leptons (electrons or muons) or a W boson decaying to a lepton (electron or muon) and a neutrino, from a data sample corresponding to an integrated luminosity of about 36 pb −1 . An estimate of the systematic uncertainty on the missing transverse momentum scale is presented.

We present an overview of the CALICE activities on calorimeter development for a future linear collider. We report on test beam analysis results, the status of prototype development and future plans.

We describe the design and operational experience of the ATLAS production system as implemented for execution on Grid3 resources. The execution environment consisted of a number of grid-based tools: Pacman for installation of VDT-based Grid3 services and ATLAS software releases, the Capone execution service built from the Chimera/Pegasus virtual data system for directed acyclic graph (DAG) generation, DAGMan/Condor-G for job submission and management, and the Windmill production supervisor which provides the Jabber messaging system for Capone interactions with the ATLAS production database at CERN. Datasets produced on Grid3 were registered into a distributed replica location service (Globus RLS) that was integrated with the Don Quijote proxy service for interoperability with other Grids used by ATLAS. We discuss performance, scalability, and fault handling during the first phase of ATLAS Data Challenge 2.

This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1, 1998 through June 30, 1998. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of Division publications and colloquia are included.

Atmospheric [nu][sub [mu]] and [nu][sub e] are created in cosmic ray interactions in the atmosphere, and can be detected in underground detectors. The Kamiokande and IMB water Cerenkov detectors have found fewer [nu][sub [mu]] interactions (relative to [nu][sub e]) than are expected. Results are usually expressed by the ratio: R[triple bond]([nu][sub [mu]]/[nu][sub [mu]]) measured ([nu][sub [mu]]/[nu][sub e]) predicted with R found to be less than 1. The Soudan 2 detector is an iron calorimeter, which has different systematic effects than the water Cerenkov counters. Results from the Frejus and NUSEX calorimeters do not suggest a deficit of [nu][sub [mu]]'s in iron, implying that perhaps there is a systematic effect in Cerenkov detectors or some unexpected nuclear effect. Here we report on a preliminary analysis of 0.5 kton-year of data in Soudan 2. We are presently analyzing our second 0.5 kt-year of data, and will present new results at the meeting.

used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal`s photo multiplier tube (PMT).