Performances of the coincidence matrix ASIC of the ATLAS barrel level-1 muon trigger (original) (raw)

The design of the coincidence matrix asic of the ATLAS barrel level-1 muon trigger

2002

Abstract The ATLAS level-1 muon trigger in the barrel region identifies candidate muon tracks within a programmable transverse momentum range. A system of seven Resistive Plate Chamber detector concentric layers provides the hit information in the bending and non-bending projection. A coincidence of hit in the detector layers within a programmable road is required to generate a trigger signal. The width of the track road in the detector is used to select the transverse momentum cut to be applied.

The coincidence matrix ASIC of the level-1 muon barrel trigger of the ATLAS experiment

2003

Abstract The ATLAS barrel level-1 muon trigger processes hit information from the resistive plate chamber detector, identifying candidate muon tracks and assigning them to a programmable p T range and to a unique bunch crossing number. The trigger system uses up to seven detector layers and seeks hit patterns compatible with muon tracks in the bending and nonbending projection. The basic principle of the algorithm is to demand a coincidence of hits in the different chamber layers within a path.

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.

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 ATLAS level-1 barrel muon trigger performances

2005

Abstract The level-1 muon trigger of ATLAS is expected to select events with high transverse momentum muons and associate them the correct bunch-crossing. For these purposes, dedicated fast detectors provide coarse measurement of the muon transverse momentum and high efficiency in its discrimination, giving also tracking measurements in two orthogonal views. In the barrel region (| eta|< 1) it makes use of resistive plate chambers (RPCs) as active detectors.

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

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).

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.

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.

Implementation and performance of the ATLAS Trigger Muon “Vertical Slice”

Nuclear Physics B - Proceedings Supplements, 2007

The ATLAS (A Toroidal LHC ApparatuS) trigger system is designed to keep high effiency for interesting events while achieving a rejection of low transverse momentum (pT) physics of about 10 7 , thus reaching the ∼200 Hz data storage capability of the Data Aquisition system. A three levels structure has been implemented for this purpose, as described in this work for the case of the muon trigger system. After describing the implementation, some performance results are presented in terms of final trigger rates, resolutions, efficiencies, background rejection and algorithm latency.