U.S. ATLAS Analysis Support Muon Software Wiki

Introduction

The purpose of the Wiki is three fold: first to serve as a starting location to obtain information about various elements of the muon software , secondly to provide links to software recipees and the location of simulated, cosmic, and test beam data, and finally to act as a repository for frequently asked questions. Note, this page is NOT meant to replace any of the Atlas muon pages as these should be centrally managed and updated for the entire experiment. Rather it is meant to facilitate the use of muon software, serve as a swichboard for information, and to record the activities of the US Atlas Muon Forum.

Muon Spectrometer Overview

A detailed description of the Muon Spectrometer can be found in the Muon Spectrometer TDR Homepage. Here we give only a breif overview of the spectrometers most salient features. The spectrometer has been designed to optimize the physics potential in both Standard Model benchmark process (W and Z production and subsequent decays, beauty physics and CP Violation) and searches for both the Stadard Model and supersymmetric Higgs as well as new heavy vector bosons. A subset of the important parameters considered were:

• Resolution: Mass and Momentum resolution at the level of 1% for intermediate Higgs masses (140-200 GeV? ) and 10% resolution of the transverse momentum resolution of 1 TeV? muons
• Second-Coordinate Measurement: A position measurement in the non-bending projection with a resolution of 5-10 mm:
• Rapidity Coverage: Eta coverage up to 2.7
• Trigger Selectivity: The capability of triggering on 'high Pt' muons with Pt > 20 GeV? and lower thresholds, 5 GeV? , required for b-physics
• Bunch-Crossing Identification: The ability to resolve the proper bunch-crossing given the LHC bunch-crossing interval of 25 ns
• Background Conditions: Coping with the high level of particle fluxes from the intense radiation environment at the LHC.

In order to achive these goals a sophisticated spectrometer has been designed comprised of three torioid magnets (one barrel and two endcap toroids) with several planes of detectors to identify and measure the momenta of the incident muons.

Annotated figures

The file MuonSpectrometer_NumHits.ppt, which is attached at the end of this page, has a tabulation of the number of hits expected for the precision and phi coordinates.

Muon Software

The main Wiki page for the Muon Spectrometer is located at the CERN Muon Spectrometer Wiki as well as the Muon Software Wiki. The items below are a subset of the items covered within the above two pages and are more comprehensive.

• Detector Description :

The Atlas Geoemetry model package is GeoModel which describes the geometry of atlas and accesses the geometry database.

• Simulation

-- KevinBlack - 15 Mar 2006

-- VivekJain - 6 June 2006

• MuonSpectrometer_nomenclature.ppt:

• MuonSpectrometer_nomenclature_Version2.ppt: Version 2

• MuonSpectrometer_NumHits.ppt: Number of precision and phi hits