The ATLAS level-1 barrel muon trigger performances (original) (raw)

Test beam results and integration of the ATLAS level-1 muon barrel trigger

2004

Abstract The ATLAS level-1 muon trigger will be crucial for the online selection of events with high transverse momentum muons and for its correct association to the bunch-crossing corresponding to the detected events. This system uses dedicated coarse granularity and fast detectors capable of providing measurements in two orthogonal projections. The resistive plate chambers (RPCs) are used in the barrel region (| η|< 1).

Performances of the ATLAS Level-1 Muon Trigger processor in the Barrel

2005

The ATLAS level-1 muon trigger will select events with high transverse momentum and tag them to the correct machine bunch-crossing number with high efficiency. Three stations of dedicated fast detectors provide a coarse pT measurement, with tracking capability on bending and non-bending projections. In the Barrel region, hits from doublets of Resistive Plate Chambers are processed by custom ASIC, the Coincidence Matrices, which performs almost all the functionalities required by the trigger algorithm and the readout.

Slice Test Results of the ATLAS Barrel Muon Level-1 Trigger

2003

Abstract The muon spectrometer of the ATLAS experiment makes use of the Resistive Plate Chambers detectors for particle tracking in the barrel region. The level-1 muon trigger system has to measure and discriminate muon transverse momentum, perform a fast and coarse tracking of the muon candidates, associate them to the bunch crossing corresponding to the event of interest, measure the second coordinate in the non-bending projection.

The Level-1 Trigger Muon Barrel System of the ATLAS experiment at CERN

Journal of Instrumentation, 2009

The ATLAS Level-1 Muon Barrel Trigger is one of the main elements of the first stage of event selection of the ATLAS experiment at the Large Hadron Collider. The challenge of the Level-1 system is a reduction of the event rate from a collision rate of 40 M Hz by a factor 10 3 , using simple algorithms that can be executed in highly parallel custom electronics with a latency of order of 1 µs. The input stage of the Level-1 Muon consists of an array of processors receiving the full granularity of data from a dedicated detector (Resistive Plate Chambers in the Barrel). This first stage of the algorithm is performed directly on-detector, while the final stage is performed on boards mounted in the counting room, by the so-called off-detector electronics. The trigger algorithm is executed within a fixed latency, its real-time output is the multiplicity of muon candidates passing a set of programmable p T thresholds, and their topological information. The detector system and the trigger electronics are designed to achieve a safe bunch-crossing identification. In order to optimize design effort and cost, the trigger system integrates also the readout of the detector, with its own requirements on time resolution and overall data bandwidth. We present the

Prototype slice of the level-1 muon trigger in the barrel region of the ATLAS experiment

2001

Abstract The ATLAS barrel level-1 muon trigger system makes use of the Resistive Plate Chamber detectors mounted in three concentric stations. Signals coming from the first two RPC stations are sent to dedicated on detector ASICs in the low-pT PAD boards, that select muon candidates compatible with a programmable pT cut of around 6 GeV, and produce an output pattern containing the low-pT trigger results.

The ATLAS Barrel Level-1 Muon Trigger Calibration

2006

Abstract The ATLAS experiment uses a system of three concentric Resistive Plate Chambers detectors layers for the level-1 muon trigger in the air-core barrel toroid region. The trigger classifies muons within different programmable transverse momentum ranges, and tags the identified tracks with the corresponding bunch crossing number. The algorithm looks for hit coincidences within different detector layers inside the programmed geometrical road which defines the transverse momentum cut.

The muon spectrometer barrel level-1 trigger of the ATLAS experiment at LHC

2006

Abstract The proton-proton beam crossing at the LHC accelerator at CERN will have a rate of 40 MHz at the project luminosity. The ATLAS Trigger System has been designed in three levels in order to select only interesting physics events reducing from that rate of 40 MHz to the foreseen storage rate of about 200 Hz. The First Level reduces the output rate to about 100 kHz.

Hardware Implementation of ATLAS Level-1 Muon Trigger in the Barrel region

1998

ABSTRACT The level-1 muon trigger of ATLAS, in the barrel region, makes use of a dedicated detector RPC, Resistive Plate Chamber. The processing procedure is accomplished through a Low Pt and a High Pt trigger. To reduce the rate of accidental triggers, due to the background noise in the cavern, for both Low Pt and High Pt, the algorithm is performed in the η and φ projections.

The ATLAS RPC Level-1 muon trigger: design and simulation

2004

The three-levels ATLAS trigger system has been designed to reduce the initial LHC interactions rate from 1GHz to∼ 100Hz in order to allow permanent data storage. This result must be achieved preserving the less probable physics signals against a large background therefore providing a challenge task for the trigger and DAQ system. The Level-1 muon trigger in the barrel region of the Muon Spectrometer is provided by Resistive Plate Chambers (RPC) working in avalanche mode.

The RPC level-1 muon trigger of the ATLAS experiment at the LHC

2004

Abstract The three-level ATLAS trigger system has been designed to reduce the initial LHC interactions rate from 1 GHz, to~ 100 Hz in order to allow permanent data storage. This result must be achieved preserving the less probable physics signals against a large background therefore providing a challenge task for the trigger and DAQ system. The level-1 muon trigger in the barrel region of the muon spectrometer is provided by resistive plate chambers (RPC) working in avalanche mode.