ATLAS semiconductor tracker installed into its barrel

CERN Multimedia

Maximilien Brice

2005-01-01

The ATLAS silicon tracker is installed in the silicon tracker barrel. Absolute precision was required in this operation to ensure that the tracker was inserted without damage through minimal clearance. The installation was performed in a clean room on the CERN site so that no impurities in the air would contaminate the tracker's systems.

Construction and Performance of the ATLAS SCT Barrels and Cosmic Tests

CERN Document Server

Demirkoz, Bilge Melahat

2007-01-01

ATLAS is a multi-purpose detector for the LHC and will detect proton-proton collisions with center of mass energy of $14$TeV. Part of the central inner detector, the Semi-Conductor Tracker (SCT) barrels, were assembled and tested at Oxford University and later integrated at CERN with the TRT (Transition Radiation Tracker) barrel. The barrel SCT is composed of 4 layers of silicon strip modules with two sensor layers with $80 \\mu$m channel width. The design of the modules and the barrels has been optimized for low radiation length while maintaining mechanical stability, bringing services to the detector, and ensuring a cold and dry environment. The high granularity, high detector efficiency and low noise occupancy ($ < 5 \\times 10^{-4}$) of the SCT will enable ATLAS to have an efficient pattern recognition capability. Due to the binary nature of the SCT read-out, a stable read-out system and the calibration system is of critical importance. SctRodDaq is the online software framework for the calibration and a...

Non-compensation of the ATLAS barrel combined calorimeter prototype

International Nuclear Information System (INIS)

Kul'chitskij, Yu.A.; Kuz'min, M.V.

1998-01-01

The e / π ratio for the ATLAS Barrel Combined Calorimeter Prototype, composed from electromagnetic LArg calorimeter and hadronic Tile calorimeter was investigated. Response of Combined Calorimeter on pions and electrons in the energy region of 20-300 GeV was studied. Found e / h = 1.37 ± 0.01 ± 0.02 is in good agreement with the results from previous Combined Calorimeter tests but has more precisions

Instrumentation of a Level-1 Track Trigger at ATLAS with Double Buffer Front-End Architecture

CERN Document Server

Cooper, B; The ATLAS collaboration

2012-01-01

Around 2021 the Large Hadron Collider will be upgraded to provide instantaneous luminosities 5x10^34, leading to excessive rates from the ATLAS Level-1 trigger. We describe a double-buffer front-end architecture for the ATLAS tracker replacement which should enable tracking information to be used in the Level-1 decision. This will allow Level-1 rates to be controlled whilst preserving high efficiency for single lepton triggers at relatively low transverse momentum thresholds pT ~25 GeV, enabling ATLAS to remain sensitive to physics at the electroweak scale. In particular, a potential hardware solution for the communication between the upgraded silicon barrel strip detectors and the external processing within this architecture will be described, and discrete event simulations used to demonstrate that this fits within the tight latency constraints.

Estimating induced-activation of SCT barrel-modules in the ATLAS radiation environment.

CERN Document Server

Buttar, C M; Dawson, I; Mandic, I; Moraes, A

2002-01-01

One of the consequences of operating detector systems in the harsh radiation environments of the ATLAS inner-detector will be radioactivation of the components. If the levels of radioactivity and corresponding dose rates are significant, then there will be implications for any access or maintenance operations. Given in this note are predictions for the radioactivation of SCT barrel-modules in the expected radiation environment of the inner-detector, based on both calculations and measurements. It is shown that both neutron-capture and high-energy hadron reactions must be taken into account. The predictions show that, from a radiological point of view, the SCT barrel-modules should not pose any serious problems.

Construction and performance of the ATLAS silicon microstrip barrel modules

International Nuclear Information System (INIS)

Kondo, T.; Apsimon, R.; Beck, G.A.; Bell, P.; Brenner, R.; Bruckman de Renstrom, P.; Carter, A.A.; Carter, J.R.; Charlton, D.; Dabrowski, W.; Dorholt, O.; Ekelof, T.; Eklund, L.; Gibson, M.; Gadomski, S.; Grillo, A.; Grosse-Knetter, J.; Haber, C.; Hara, K.; Hill, J.C.; Ikegami, Y.; Iwata, Y.; Johansen, L.G.; Kohriki, T.; Macpherson, A.; McMahon, S.; Moorhead, G.; Morin, J.; Morris, J.; Morrissey, M.; Nagai, K.; Nakano, I.; Pater, J.; Pernegger, H.; Perrin, E.; Phillips, P.; Robinson, D.; Skubic, B.; Spencer, N.; Stapnes, S.; Stugu, B.; Takashima, R.; Terada, S.; Tyndel, M.; Ujiie, N.; Unno, Y.; Vos, M.

2002-01-01

The ATLAS Semiconductor Tracker (SCT) consists of four barrel cylinders and 18 end-cap disks. This paper describes the SCT modules of the barrel region, of which more than 2000 are about to be constructed. The module design is fixed. Its design concept is given together with the electrical, thermal and mechanical specifications. The pre-series production of the barrel modules is underway using mass-production procedures and jigs. The pre-series modules have given satisfactory performances on noise, noise occupancy, electrical as well as mechanical and thermal properties. In addition, irradiated modules were demonstrated to work successfully. Also first results from a 10-module system test are given

Cryogenic Characteristics of the ATLAS Barrel Toroid Superconducting Magnet

CERN Document Server

Pengo, R; Delruelle, N; Pezzetti, M; Pirotte, O; Passardi, Giorgio; Dudarev, A; ten Kate, H

2008-01-01

ATLAS, one of the experiments of the LHC accelerator under commissioning at CERN, is equipped with a large superconducting magnet the Barrel Toroid (BT) that has been tested at nominal current (20500 A). The BT is composed of eight race-track superconducting coils (each one weights about 45 tons) forming the biggest air core toroidal magnet ever built. By means of a large throughput centrifugal pump, a forced flow (about 10 liter/second at 4.5 K) provides the indirect cooling of the coils in parallel. The paper describes the results of the measurements carried out on the complete cryogenic system assembled in the ATLAS cavern situated 100 m below the ground level. The measurements include, among other ones, the static heat loads, i.e., with no or constant current in the magnet, and the dynamic ones, since additional heat losses are produced, during the current ramp-up or slow dump, by eddy currents induced on the coil casing.

ATLAS barrel hadron tile calorimeter: spacers plates mass production

International Nuclear Information System (INIS)

Artikov, A.M.; Budagov, Yu.A.; Khubua, J.

1999-01-01

In this article we expose the main problems of the mass production of the so-called 'spacer plates' for the ATLAS Barrel Hadron Tile Calorimeter. We describe all practical solutions of these problems. Particularly we present the measurement procedures and calculation schemes we used for the spacers dimensions determination. The results of the calculations are presented

Robotic mounting of ATLAS barrel SCT modules

International Nuclear Information System (INIS)

Nickerson, R.B.; Viehhauser, G.; Wastie, R.; Terada, S.; Unno, Y.; Kohriki, T.; Ikegami, Y.; Hara, K.; Kobayashi, H.; Barbier, G.; Clark, A.G.; Perrin, E.; Carter, A.A.; Mistry, J.; Morris, J.

2006-01-01

The 2112 silicon detector modules of the barrel part of the ATLAS SemiConductor Tracker (SCT) have been mounted on their carbon fibre support structure. Module insertion, placement and fixing were performed by robotic assembly tooling. We report on our experience with this assembly method. Part of the mounting sequence involves a partial survey of elements of the support structure which is needed to align the modules properly during insertion. An analysis of these data is used to estimate the positional accuracy of the robots

Supporting ATLAS

CERN Multimedia

2003-01-01

Eighteen feet made of stainless steel will support the barrel ATLAS detector in the cavern at Point 1. In total, the ATLAS feet system will carry approximately 6000 tons, and will give the same inclination to the detector as the LHC accelerator. The installation of the feet is scheduled to finish during January 2004 with an installation precision at the 1 mm level despite their height of 5.3 metres. The manufacture was carried out in Russia (Company Izhorskiye Zavody in St. Petersburg), as part of a Russian and JINR Dubna in-kind contribution to ATLAS. Involved in the installation is a team from IHEP-Protvino (Russia), the ATLAS technical co-ordination team at CERN, and the CERN survey team. In all, about 15 people are involved. After the feet are in place, the barrel toroid magnet and the barrel calorimeters will be installed. This will keep the ATLAS team busy for the entire year 2004.

Work on a ATLAS tile calorimeter Barrel

CERN Multimedia

Laurent Guiraud

2000-01-01

The Tile Calorimeter is designed as one barrel and two extended barrel hadron parts. The calorimeter consists of a cylindrical structure with inner and outer radius of 2280 and 4230 mm respectively. The barrel part is 5640 mm in length along the beam axis, while each of the extended barrel cylinders is 2910 mm long. Each detector cylinder is built of 64 independent wedges along the azimuthal direction. Between the barrel and the extended barrels there is a gap of about 600 mm, which is needed for the Inner Detector and the Liquid Argon cables, electronics and services. The barrel covers the region -1.01.0, and the extended barrels cover the region 0.8<|h|<1.7.

SCT Barrel Assembly Complete

CERN Multimedia

L. Batchelor

As reported in the April 2005 issue of the ATLAS eNews, the first of the four Semiconductor Tracker (SCT) barrels, complete with modules and services, arrived safely at CERN in January of 2005. In the months since January, the other three completed barrels arrived as well, and integration of the four barrels into the entire barrel assembly commenced at CERN, in the SR1 building on the ATLAS experimental site, in July. Assembly was completed on schedule in September, with the addition of the innermost layer to the 4-barrel assembly. Work is now underway to seal the barrel thermal enclosure. This is necessary in order to enclose the silicon tracker in a nitrogen atmosphere and provide it with faraday-cage protection, and is a delicate and complicated task: 352 silicon module powertapes, 352 readout-fibre bundles, and over 400 Detector Control System sensors must be carefully sealed into the thermal enclosure bulkhead. The team is currently verifying the integrity of the low mass cooling system, which must be d...

Second Barrel Toroid Coil Installed in ATLAS Cavern

CERN Multimedia

Tappern, G.

The second barrel toroid coil was lowered into the ATLAS Cavern on Friday, 26 November. The operation takes approximately five hours of precision crane and winch operations. Before lowering, several checks are made to ensure that no loose items have been left on the coil which would fall during the lowering down the shaft. This is a very difficult, but very important check, with the first coil in position, and partly below the shaft. After changing the winch tooling on Wednesday December 1st, the coil was lifted, rotated and placed into the feet. The girders which support the coil and the Z direction stops had all been pre-set before putting the coil in the feet. The angle is controlled by an inclinometer. When the final adjustments of position have been made, which will locate the coils at the plus/minus two mm level, the connection beams (voussoirs and struts) will be put in place; this requires a complex shimming procedure. This will lock together the two coils into the feet and forms the foundation for th...

Design and development of a work robot to place ATLAS SCT modules onto barrel cylinders

International Nuclear Information System (INIS)

Terada, S.; Kobayashi, H.; Sengoku, H.; Kato, Y.; Hara, K.; Honma, F.; Ikegami, Y.; Iwata, Y.; Kohriki, T.; Kondo, T.; Nakano, I.; Takashima, R.; Tanaka, R.; Ujiie, N.; Unno, Y.; Yasuda, S.

2005-01-01

More than 2000 silicon modules need to be placed and fastened on the ATLAS SCT barrel tracker. A semi-automatic pick-and-place work robot was designed and developed to cope with the module placement for the SCT barrel assembly. We found that this robot could place modules to a mechanical precision of better than 25 μm

Design and development of a work robot to place ATLAS SCT modules onto barrel cylinders

CERN Document Server

Terada, S; Honma, F; Ikegami, Y; Iwata, Y; Kato, Y; Kobayashi, H; Kohriki, T; Kondo, T; Nakano, I; Sengoku, H; Takashima, R; Tanaka, R; Ujiie, N; Unno, Y; Yasuda, S

2005-01-01

More than 2000 silicon modules need to be placed and fastened on the ATLAS SCT barrel tracker. A semi-automatic pick-and-place work robot was designed and developed to cope with the module placement for the SCT barrel assembly. We found that this robot could place modules to a mechanical precision of better than 25 mum.

Signal feedthroughs for the ATLAS barrel and endcap calorimeters

International Nuclear Information System (INIS)

Axen, D.; Hackenburg, R.; Hoffmann, A.; Kane, S.; Lissauer, D.; Makowiecki, D.; Muller, T.; Pate, D.; Radeka, V.; Rahm, D.; Rehak, M.; Rescia, S.; Sexton, K.; Sondericker, J.; Birney, P.; Dowling, A.W.; Fincke-Keeler, M.; Hodges, T.; Holness, F.; Honkanen, N.

2005-01-01

The function, design, construction, testing, and installation of the signal feedthroughs for the barrel and endcap ATLAS liquid argon calorimeters are described. The feedthroughs provide a high density and radiation hard method to extract over 200 000 signals from the cryogenic environment of the calorimeters using an application of a design based on flexible kapton circuit board transmission lines. A model to describe the frequency dependent behavior of the transmission lines is also presented

Design of the LHC US ATLAS Barrel Cryostat

CERN Document Server

Rehak, M L; Farah, Y; Grandinetti, R; Müller, T; Norton, S; Sondericker, J

2002-01-01

One of the experiments of CERN's Large Hadron Collider (LHC) is the ATLAS Liquid Argon detector. The Liquid Argon Barrel Cryostat is part of the United States contribution to the LHC project and its design is presented here. The device is made up of four concentric cylinders: the smallest and largest of which form a vacuum vessel enclosing a cold vessel cryostat filled with liquid argon. The Cryostat serves as the housing for an electromagnetic barrel calorimeter, supports and provides space in vacuum for a solenoid magnet while the toroidal opening furnishes room for a tracker detector. Design requirements are determined by its use in a collider experiment: the construction has to be compact, the material between the interaction region and the calorimeter has to be minimal and made of aluminum to reduce the amount of absorbing material. The design complies with code regulations while being optimized for its use in a physics environment. (2 refs).

Hadron Energy Reconstruction for ATLAS Barrel Combined Calorimeter Using Non-Parametrical Method

CERN Document Server

Kulchitskii, Yu A

2000-01-01

Hadron energy reconstruction for the ATLAS barrel prototype combined calorimeter in the framework of the non-parametrical method is discussed. The non-parametrical method utilizes only the known e/h ratios and the electron calibration constants and does not require the determination of any parameters by a minimization technique. Thus, this technique lends itself to fast energy reconstruction in a first level trigger. The reconstructed mean values of the hadron energies are within \\pm1% of the true values and the fractional energy resolution is [(58\\pm 3)%{\\sqrt{GeV}}/\\sqrt{E}+(2.5\\pm0.3)%]\\bigoplus(1.7\\pm0.2) GeV/E. The value of the e/h ratio obtained for the electromagnetic compartment of the combined calorimeter is 1.74\\pm0.04. Results of a study of the longitudinal hadronic shower development are also presented.

Certification and commissioning of barrel stations for the ATLAS muon spectrometer

CERN Document Server

Zimmermann, S

2006-01-01

The muon spectrometer of the ATLAS experiment, which is scheduled to commence data taking at the Large Hadron Collider, LHC at CERN in 2007, comprises more than a thousand muon stations, which have the double purpose of triggering on high-p/sub t/ muon tracks as well as providing precise trajectory reconstruction. While monitored drift tube chambers are used for track reconstruction in all of the muon spectrometer except for a region close to the beam pipe in forward direction, two different technologies are used for triggering, resistive plate chambers in the barrel region and thin gap chambers in the end-caps. Both have in common that the ATLAS geometry allows only limited accessibility after chambers are installed in the detector. A thorough testing and certification prior to installation is therefore crucial. This paper reviews the test procedure at CERN for barrel chambers of type BO and BM, i.e. of stations for which a drift chamber is coupled with one or two resistive plate chambers. The final certific...

ID Barrel installed in cryostat

CERN Multimedia

Apsimon, R.; Romaniouk, A.

Wednesday 23rd August was a memorable day for the Inner Detector community as they witnessed the transport and installation of the central part of the inner detector (ID-barrel) into the ATLAS detector. Many members of the collaboration gathered to witness this moment at Point 1. After years of design, construction and commissioning, the outer two detectors (TRT and SCT) of the ID barrel were moved from the SR1 cleanroom to the ATLAS cavern. The barrel was moved across the car park from building 2175 to SX1. Although only a journey of about 100 metres, this required weeks of planning and some degree of luck as far as the weather was concerned. Accelerometers were fitted to the barrel to provide real-time monitoring and no values greater than 0.1 g were recorded, fully satisfying the transport specification for this extremely precise and fragile detector. Muriel, despite her fear of heights, bravely volunteered to keep a close eye on the detector. Swapping cranes to cross the entire parking lot, while Mur...

Performance of ATLAS RPC Level-1 muon trigger during the 2015 data taking

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00001854; The ATLAS collaboration

2016-01-01

RPCs are used in the ATLAS experiment at the LHC for muon trigger in the barrel region, which corresponds to |eta|<1.05. The status of the barrel trigger system during the 2015 data taking is presented, including measurements of the RPC detector efficiencies and of the trigger performance. The RPC system has been active in more than 99.9% of the ATLAS data taking, showing very good reliability. The RPC detector efficiencies were close to Run-1 and to design value. The trigger efficiency for the high-pT thresholds used in single-muon triggers has been approximately 4% lower than in Run 1, mostly because of chambers disconnected from HV due to gas leaks. Two minor upgrades have been performed in preparation of Run 2 by adding the so-called feet and elevator chambers to increase the system acceptance. The feet chambers have been commissioned during 2015 and are included in the trigger since the last 2015 runs. Part of the elevator chambers are still in commissioning phase and will probably need a replacement ...

Cosmic tests and performance of the ATLAS SemiConductor Tracker Barrels

International Nuclear Information System (INIS)

Demirkoez, Bilge M.

2007-01-01

ATLAS is a multi-purpose particle detector for the LHC and will detect proton collisions with center of mass energy of 14TeV. Part of the central inner detector, the SemiConductor Tracker (SCT) barrel, is now fully integrated with the Transition Radiation Tracker (TRT) barrel. The SCT module performance has been measured after module production, after macro-assembly of modules onto barrels, after arrival at CERN and again partially after integration with the TRT. The module noise average per channel has been stable and is 4.5x10 -5 , well below the design specification of 5x10 -4 . There is no evidence for common mode noise problems and 99.8% of the 3.2 million channels of the SCT barrels are functional. The cosmics running of the SCT and TRT was the first large scale test of the physics mode of the SCT online software framework. A large sector, 468 SCT modules, has been timed in and read out during the cosmic tests. Tracks have been reconstructed through the SCT and the TRT sectors. Present residuals from tracks (without alignment) are better than the specified building tolerances of the SCT

The ATLAS installation team, led by Tommi Nyman, after having positioned the Barrel Calorimeter in its final location in the ATLAS experimental cavern UX15

CERN Multimedia

2005-01-01

On Friday 4th November, the ATLAS Barrel Calorimeter was moved from its assembly point at the side of the ATLAS cavern to the centre of the toroidal magnet system. The detector was finally aligned, to the precision of within a millimetre, on Wednesday 9th November.

Last Few Metres for the Barrel Calorimeter

CERN Multimedia

Nyman, T.

On Friday 4th November, the ATLAS Barrel Calorimeter was moved from its assembly point at the side of the ATLAS cavern to the centre of the toroidal magnet system. The detector was finally aligned, to the precision of within a millimetre, on Wednesday 9th November. The ATLAS installation team, led by Tommi Nyman, after having positioned the Barrel Calorimeter in its final location in the ATLAS experimental cavern UX15. The Barrel Calorimeter which will absorb and measure the energy of photons, electrons and hadrons at the core of the ATLAS detector is 8.6 meters in diameter, 6.8 meters long, and weighs over 1600 Tonnes. It consists of two concentric cylindrical detector elements. The innermost comprises aluminium pressure vessels containing the liquid argon electromagnetic calorimeter and the solenoid magnet. The outermost is an assembly of 64 hadron tile calorimeter sectors. Assembled 18 meters away from its final position, the Barrel Calorimeter was relocated with the help of a railway, which allows ...

Application of advanced thermal management technologies to the ATLAS SCT barrel module baseboards

Energy Technology Data Exchange (ETDEWEB)

Apsimon, R.J. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 OQX (United Kingdom); Batchelor, L.E. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 OQX (United Kingdom); Beck, G.A. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Canard, P. [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Carter, A.A. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)]. E-mail: a.a.carter@qmul.ac.uk; Carter, J.R. [Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Davis, V.R. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 OQX (United Kingdom); Oliveira, R. de [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Gibson, M.D. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 OQX (United Kingdom); Hominal, L. [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Ilie, D.M. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Ilie, S.D. [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Leboube, C.G. [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Mistry, J. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Morin, J. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Morris, J.; Nagai, K. [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Sexton, I.; Thery, X. [European Laboratory for Particle Physics (CERN), 1211 Geneva 23 (Switzerland); Tyndel, M. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 OQX (United Kingdom)

2006-09-15

The paper describes the application of advanced thermal management technologies to the design and production of the barrel module baseboard of the SemiConductor Tracker (SCT) of the ATLAS experiment at the Large Hadron Collider (LHC). The barrel modules contain silicon microstrip sensors and readout ASICs for tracking charged particles, and the baseboard forms the central element of the module, providing both its necessary thermal management and its mechanical structure. The baseboard requirements and specifications are given, and design and fabrication details are described. The properties of the 3000 baseboards successfully produced for the SCT are summarised.

ATLAS barrel toroid integration and test area in building 180

CERN Multimedia

Maximilien Brice

2003-01-01

The ATLAS barrel toroid system consists of eight coils, each of axial length 25.3 m, assembled radially and symmetrically around the beam axis. The coils are of a flat racetrack type with two 'double-pancake' windings made of 20.5 kA aluminium-stabilized niobium-titanium superconductor. The barrel toroid is being assembled in building 180 on the Meyrin site. In the first phase of assembly, the coils are packed into their aluminium-alloy casing. These photos show the double-pancake coils from ANSALDO and the coil casings from ALSTOM. In the foreground is the tooling from COSMI used to turn over the coil casings during this first phase. In the right background is the yellow lifting gantry manufactured at JINR-Dubna, Russia which will transport the coil casings to a heating table for prestressing. Two test benches with magnetic mirror are also visible.

The ATLAS Level-1 Calorimeter Trigger

International Nuclear Information System (INIS)

Achenbach, R; Andrei, V; Adragna, P; Apostologlou, P; Barnett, B M; Brawn, I P; Davis, A O; Edwards, J P; Asman, B; Bohm, C; Ay, C; Bauss, B; Bendel, M; Dahlhoff, A; Eckweiler, S; Booth, J R A; Thomas, P Bright; Charlton, D G; Collins, N J; Curtis, C J

2008-01-01

The ATLAS Level-1 Calorimeter Trigger uses reduced-granularity information from all the ATLAS calorimeters to search for high transverse-energy electrons, photons, τ leptons and jets, as well as high missing and total transverse energy. The calorimeter trigger electronics has a fixed latency of about 1 μs, using programmable custom-built digital electronics. This paper describes the Calorimeter Trigger hardware, as installed in the ATLAS electronics cavern

The ATLAS Level-1 Calorimeter Trigger

Energy Technology Data Exchange (ETDEWEB)

Achenbach, R; Andrei, V [Kirchhoff-Institut fuer Physik, University of Heidelberg, D-69120 Heidelberg (Germany); Adragna, P [Physics Department, Queen Mary, University of London, London E1 4NS (United Kingdom); Apostologlou, P; Barnett, B M; Brawn, I P; Davis, A O; Edwards, J P [STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX (United Kingdom); Asman, B; Bohm, C [Fysikum, Stockholm University, SE-106 91 Stockholm (Sweden); Ay, C; Bauss, B; Bendel, M; Dahlhoff, A; Eckweiler, S [Institut fuer Physik, University of Mainz, D-55099 Mainz (Germany); Booth, J R A; Thomas, P Bright; Charlton, D G; Collins, N J; Curtis, C J [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom)], E-mail: e.eisenhandler@qmul.ac.uk (and others)

2008-03-15

The ATLAS Level-1 Calorimeter Trigger uses reduced-granularity information from all the ATLAS calorimeters to search for high transverse-energy electrons, photons, {tau} leptons and jets, as well as high missing and total transverse energy. The calorimeter trigger electronics has a fixed latency of about 1 {mu}s, using programmable custom-built digital electronics. This paper describes the Calorimeter Trigger hardware, as installed in the ATLAS electronics cavern.

Triggering and measuring bent cosmic muon tracks with the Muon Spectrometer barrel for the first time

CERN Multimedia

Fabio Cerutti

During the ATLAS barrel toroid stability test, bent cosmic muon tracks were seen for the first time in the ATLAS cavern by means of the ATLAS muon spectrometer. The barrel toroid has been powered at its nominal current (20.5 thousand Amperes) and kept in steady state for more than one day during the weekend of 18-19 November (see a report on this test in the Magnet section). During this test one large sector and part of a small sector of the barrel muon spectrometer were readout and used to detect the cosmic muons tracks bent by the toroidal magnetic field. Thirteen muon stations in the feet sectors (sectors 13 and 14) have been used in this test. The muon stations are formed of Resistive Plate Chambers (RPC) that were providing the muon trigger, and Monitored Drift Tubes that were used to measure with high accuracy the muon curvature hence their momentum. The Level-1 Barrel trigger chain was based on the Barrel Middle Large chambers equipped with final production modules on both the on-detector and the o...

Non-compensation of the ATLAS barrel tile hadron module-0 calorimeter

International Nuclear Information System (INIS)

Kul'chitskij, Yu.A.; Vinogradov, V.B.

1999-01-01

The detailed experimental information about the electron and pion responses, the electron energy resolution and the elh ratio as a function of incident energy E, impact point Z and incidence angle Θ of the Module-0 of the ATLAS iron-scintillator barrel hadron calorimeter with the longitudinal tile configuration is presented. The results are based on the electron and pion beams data for E = 10, 20, 60, 80, 100 and 180 GeV at η = - 0.25 and -0.55, which have been obtained during the test beam period in 1996. The results are compared with the existing experimental data of TILECAL 1m prototype modules, various iron-scintillator calorimeters and with some Monte Carlo calculations

Insertion of the first half-barrel of the ATLAS electromagnetic calorimeter into its cryostat

CERN Multimedia

Maximilien Brice

2003-01-01

The first cylinder of the ATLAS electromagnetic calorimeter barrel and the presampler have been inserted in the cryostat.The ATLAS electromagnetic calorimeter is intended to detect electrons, positrons and photons by measuring the energy they deposit on being absorbed. The cylinder of the calorimeter is in two halves, that will be sunk in a liquid-argon bath cooled to 90 kelvin (-180°C). Each half-barrel is 3.2 metres long, 53 cm thick and formed by assembling 16 modules. Each module is made up of alternate lead absorbers and electrodes pressed into 64 layers folded accordion-fashion. The presampler, set up inside the cylinder, is an integral part of the calorimeter system: It measures the energy lost by a particle before it reaches the calorimeter. To ensure an ultra-clean environment, a tent (visible here) was erected round the calorimeter and entry point to the cryostat. The detector and presampler, fitted together, could then be slid gradually into the cryostat like a drawer. To do so, the insertion team...

Insertion of the first half-barrel of the ATLAS electromagnetic calorimeter into its cryostat

CERN Multimedia

Maximilien Brice

2003-01-01

The first cylinder of the ATLAS electromagnetic calorimeter barrel and the presampler have been inserted in the cryostat. The ATLAS electromagnetic calorimeter is intended to detect electrons, positrons and photons by measuring the energy they deposit on being absorbed. The cylinder of the calorimeter is in two halves, that will be sunk in a liquid-argon bath cooled to 90 kelvin (-180°C). Each half-barrel is 3.2 metres long, 53 cm thick and formed by assembling 16 modules. Each module is made up of alternate lead absorbers and electrodes pressed into 64 layers folded accordion-fashion. The presampler, set up inside the cylinder, is an integral part of the calorimeter system: It measures the energy lost by a particle before it reaches the calorimeter. To ensure an ultra-clean environment, a tent was erected round the calorimeter and entry point to the cryostat. The detector and presampler, fitted together, could then be slid gradually into the cryostat like a drawer. To do so, the insertion team had to fine-t...

First ATLAS Barrel Toroid coil casing arrives at CERN

CERN Multimedia

2002-01-01

The first of eight 25-metre long coil casings for the ATLAS experiment's barrel toroid magnet system arrived at CERN on Saturday 2 March by road from Heidelberg. This structure will be part of the largest superconducting toroid magnet ever made.   The first coil casing for the toroidal magnets of Atlas arrives at Building 180. This is the start of an enormous three-dimensional jigsaw puzzle. Each of the eight sets of double pancake coils will be housed inside aluminium coil casings, which in turn will be held inside a stainless steel vacuum vessel. A huge construction, the casing that arrived at CERN measures 25 metres in length and 5 metres in width. It weighs 20 tones. And this is just the beginning of the toroid jigsaw: by early April a batch of four double pancake coils, which altogether weighs 65 tones, will arrive from Ansaldo in Italy. The first vacuum vessel will also be arriving from Felguera in Spain this month. It will take about two years for all these 25 m long structures of casings, coils a...

Evaporating short-circuits in the ATLAS liquid argon barrel presampler 006

CERN Document Server

Belhorma, B; Lund-Jensen, B; Rydström, S; Yamouni, M

2005-01-01

A technique to eliminate or limit the implications of short-circuits in the ATLAS barrel presampler is described. A high voltage capacitor with a large capacity is charged at different high voltages and discharged through the short-circuit which allows either to disintegrate the dust being the origin of the short-circuit, or to burn away a thin etched copper strip which acts as a fuse on the corresponding presampler anode. This effect is possible even in the presence of a resistive HV cable (10 to 30 ohms) in series which dampens the pulse.

ATLAS Award for Difficult Task : two Russian companies were honoured with an ATLAS Award, for supply of the ATLAS Inner Detector barrel support structure elements, last week.

CERN Multimedia

2004-01-01

From left to right, V. Riadovikov (IHEP Protvino), N. Voronkov (RSPKrunitchev), J. Margoulis (RSP Krunitchev), D. Froidevaux (CERN), A. Romashin (ORPE Technologiya), J. Callahan (CERN/Indiana University), A. Catinaccio (CERN) and O. Komissar (ORPE Technologiya), stand in front of the ATLAS inner detector barrel support structure, manufactured by ORPE Technologiya and RSP Krunitchev.

The ATLAS Level-1 Topological Trigger Performance

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00371751; The ATLAS collaboration

2016-01-01

The LHC will collide protons in the ATLAS detector with increasing luminosity through 2016, placing stringent operational and physical requirements to the ATLAS trigger system in order to reduce the 40 MHz collision rate to a manageable event storage rate of 1 kHz, while not rejecting interesting physics events. The Level-1 trigger is the first rate-reducing step in the ATLAS trigger system with an output rate of 100 kHz and decision latency smaller than 2.5 μs. It consists of a calorimeter trigger, muon trigger and a central trigger processor. During the LHC shutdown after the Run 1 finished in 2013, the Level-1 trigger system was upgraded including hardware, firmware and software updates. In particular, new electronics modules were introduced in the real-time data processing path: the Topological Processor System (L1Topo). It consists of a single AdvancedCTA shelf equipped with two Level-1 topological processor blades. They receive real-time information from the Level-1 calorimeter and muon triggers, which...

First SCT Barrel arrives at CERN

CERN Multimedia

Apsimon, R

Mid-January saw the arrival at CERN of Barrel #3, the first of four SCT barrels. The barrels are formed as low-mass cylinders of carbon fibre skins on a honeycomb carbon core. They are manufactured in industry and then have all the final precision supports added and the final geometric metrology carried out at Geneva University. Barrel #3, complete with its 384 silicon detector modules, arrived by road from Oxford University in England where the modules were mounted using a purpose-built robot. The modules had been selected from the output of all four barrel module building clusters (in Japan, Scandinavia, USA and the UK). Since Barrel #3 will be exposed to high radiation levels within the tracker volume, these modules, representing over half a million readout channels, have been extensively tested at their operational temperature of around -25 degrees Celcius and at voltages of up to 500V. The dangers of shipping such a fragile component of ATLAS were apparent to all and considerable attention was focused...

The TileCal Barrel Test Assembly

CERN Multimedia

Leitner, R

On 30th October, the mechanics test assembly of the central barrel of the ATLAS tile hadronic calorimeter was completed in building 185. It started on 23rd June and is the second wheel for the Tilecal completely assembled this year. The ATLAS engineers and technicians are quick: instead of the 27 weeks initially foreseen for assembling the central barrel of the tile hadronic calorimeter (Tilecal) in building 185, they inserted the last of the 64 modules on 30th October after only 19 weeks. In part, this was due to the experience gained in the dry run assembly of the first extended barrel, produced in Spain, in spring this year (see Bulletin 23/2003); however, the central barrel is twice as long - and twice as heavy. With a length of 6.4 metres, an outer diameter of 8.5 metres and an inner diameter of 4.5 metres, the object weight is 1300 tonnes. The whole barrel cylinder is supported by the stainless steel support structure weighing only 27 tons. The barrel also has to have the right shape: over the whole 8...

Study of a twisted ATLAS SCT Barrel deformation as revealed by a photogrammetric survey

CERN Document Server

Dobson, E; Heinemann, F; Karagoz-Unel, M

2007-01-01

A photogrammetry survey on the SCT barrels was performed as an engineering check on the structure of the ATLAS Semiconductor Tracker (SCT) shortly after construction. Analysis of the data obtained revealed small scale elliptical deformation as well as a twist of the structure. The results of the survey are presented as well as interpolation of the measured targets to the module positions and a comparison with track based alignment measurements.

First Cool-down and Test at 4.5 K of the ATLAS Superconducting Barrel Toroid Assembled in the LHC Experimental Cavern

CERN Document Server

Barth, K; Dudarev, A; Passardi, Giorgio; Pengo, R; Pezzetti, M; Pirrote, O; Ten Kate, H; Baynham, E; Mayri, C

2008-01-01

The large ATLAS superconducting magnets system consists of the Barrel, two End-Caps Toroids and the Central Solenoid. The eight separate coils making the Barrel Toroid (BT) have been individually tested with success in a dedicated surface test facility in 2004 and 2005 and afterwards assembled in the underground cavern of the ATLAS experiment. In order to fulfil all the cryogenic scenarios foreseen for these magnets with a cold mass of 370 tons, two separate helium refrigerators and a complex helium distribution system have been used. This paper describes the results of the first cool-down, steady-state operation at 4.5 K and quench recovery of the BT in its final configuration.

Performance studies of the ATLAS transition radiation tracker barrel using SR1 cosmics data

CERN Document Server

Wall, R

The ATLAS experiment at the Large Hadron Collider (LHC) is designed to measure Nature at the energy scale often associated with electroweak symmetry breaking. When it comes online in 2008, the LHC and ATLAS will work to discover, among other things, the Higgs boson and any other signatures for physics beyond the Standard Model. As part of the ATLAS Inner Detector, the Transition Radiation Tracker will be an important part of ATLAS’s ability to make precise measurements of particle properties. This paper summarizes work done to study and categorize the performance of the TRT, using a combination of cosmic ray test data from the SR1 facility and Monte Carlo. In general, it was found that the TRT is working well, with module-level eciencies around 90 % and module-level noise just above 2 %. Reasonably good agreement was observed with Monte Carlo, though there are some apparently pathological dierences between the two that deserve further attention.

ATLAS Calorimeter system: Run-2 performance, Phase-1 and Phase-2 upgrades

CERN Document Server

Starz, Steffen; The ATLAS collaboration

2018-01-01

The ATLAS detector was designed and built to study proton-proton collisions produced at the LHC at centre-of-mass energies up to 14 TeV and instantaneous luminosities up to 10^{34} cm^{−2} s^{−1}. A liquid argon-lead sampling calorimeter (LAr) is employed as electromagnetic calorimeter and hadronic calorimeter, except in the barrel region, where a scintillator-steel sampling calorimeter (TileCal) is used as hadronic calorimeter. ATLAS recorded 87 fb^{-1} of data at a center-of-mass energy of 13 TeV between 2015 and 2017. In order to achieve the level-1 acceptance rate of 100 kHz, certain adjustments have been performed. The calorimetry system performed accordingly to its design values and have played a crucial role in the ATLAS physics programme. This contribution will give an overview of the detector operation, monitoring and data quality, as well as the achieved performance, including the calibration and stability of the energy scale, noise level, response uniformity and time resolution of the ATLAS cal...

A cosmic ray muon recorded by the ATLAS barrel tile calorimeter at 18:30, on 21 June 2005.

CERN Multimedia

2005-01-01

The ATLAS barrel tile calorimeter has recorded its first events underground using a cosmic ray trigger, as part of the detector commissioning programme. The calorimeter has three layers and a pointing geometry. The light trapezoids represent the energy deposited in the tiles of the calorimeter depicted as a thick disk.

Supporting ATLAS

CERN Multimedia

maximilien brice

2003-01-01

Eighteen feet made of stainless steel will support the barrel ATLAS detector in the cavern at Point 1. In total, the ATLAS feet system will carry approximately 6000 tons, and will give the same inclination to the detector as the LHC accelerator.

ATLAS Level-1 Calorimeter Trigger: Status and Development

CERN Document Server

Bracinik, J; The ATLAS collaboration

2013-01-01

The ATLAS Level-1 Calorimeter Trigger seeds all the calorimeter-based triggers in the ATLAS experiment at LHC. The inputs to the system are analogue signals of reduced granularity, formed by summing cells from both the ATLAS Liquid Argon and Tile calorimeters. Several stages of analogue then digital processing, largely performed in FPGAs, refine these signals via configurable and flexible algorithms into identified physics objects, for example electron, tau or jet candidates. The complete processing chain is performed in a pipelined system at the LHC bunch-crossing frequency, and with a fixed latency of about 1us. The first LHC run from 2009-2013 provided a varied and challenging environment for first level triggers. While the energy and luminosity were below the LHC design, the pile-up conditions were similar to the nominal conditions. The physics ambitions of the experiment also tested the performance of the Level-1 system while keeping within the rate limits set by detector readout. This presentation will ...

ATLAS: Full power for the toroid magnet

CERN Multimedia

2006-01-01

The 9th of November was a memorable day for ATLAS. Just before midnight, the gigantic Barrel toroid magnet reached its nominal field of 4 teslas in the coil windings, with an electrical current of 21000 amperes (21 kA) passing through the eight superconducting coils (as seen on the graph). This achievement was obtained after several weeks of commissioning. The ATLAS Barrel Toroid was first cooled down for about six weeks in July-August to -269°C (4.8 K) and then powered up step-by-step in successive test sessions to 21 kA. This is 0.5 kA above the current required to produce the nominal magnetic field. Afterwards, the current was safely switched off and the stored magnetic energy of 1.1 gigajoules was dissipated in the cold mass, raising its temperature to a safe -218°C (55 K). 'We can now say that the ATLAS Barrel Toroid is ready for physics,' said Herman ten Kate, project leader for the ATLAS magnet system. The ATLAS barrel toroid magnet is the result of a close collaboration between the magnet la...

ATLAS Transition Region Upgrade at Phase-1

CERN Document Server

Song, H; The ATLAS collaboration

2014-01-01

This report presents the L1 Muon trigger transition region (1.0<|ƞ|<1.3) upgrade of ATLAS Detector at phase-1. The high fake trigger rate in the Endcap region 1.0<|ƞ|<2.4 would become a serious problem for the ATLAS L1 Muon trigger system at high luminosity. For the region 1.3<|ƞ|<2.4, covered by the Small Wheel, ATLAS is enhancing the present muon trigger by adding local fake rejection and track angle measurement capabilities. To reduce the rate in the remaining ƞ interval it has been proposed a similar enhancement by adding at the edge of the inner barrel a structure of 3-layers RPCs of a new generation. These RPCs will be based on a thinner gas gap and electrodes with respect to the ATLAS standards, a new high performance Front End, integrating fast TDC capabilities, and a new low profile and light mechanical structure allowing the installation in the tiny space available.This design effectively suppresses fake triggers by making the coincidence with both end-cap and interaction point...

Design optimisation of the ATLAS Barrel Toroid structure - the warm structure

International Nuclear Information System (INIS)

Daeel, A.; Desvard, J-P.; Pabot, Y.; Sun, Z.; Hille, H. van; Vedrine, P.

2001-01-01

The magnetic bending of muon tracks for the ATLAS Muon Spectrometer is provided by the large air-core toroid magnets. The Barrel Toroid structure, named the warm structure, is an open structure inside which the muon chambers are installed. The physics performance of the muon spectrometer imposes stringent requirements on the design of the warm structure. It should support the muon chambers with required precision and stability, the deformation of the structure must be minimised. At the same time, the quantities of the materials used in the structure must also be minimised. Through extensive structural analyses, the design optimisation has been achieved to fit with the physics requirements. This paper gives an overview on the design considerations of the warm structure

Manufacturing aspects of the ATLAS barrel toroid double pancakes

CERN Document Server

Drago, G; Gagliardi, P; Laurenti, A; Marabotto, R; Penco, R

2002-01-01

In 1999 INFN (Istituto Nazionale di Fisica Nucleare) ordered to ANSALDO the manufacturing of 16 double pancakes for the ATLAS BARREL TOROID. In July 2001 four Double Pancakes have already been completed and shipped to the integration site. In this paper the main aspects of the manufacturing of the largest superconducting coils ever built (5*25 m) are described. The main phases of the manufacturing procedure are reviewed starting from the conductor preparation to the VPI impregnation, including references to the materials used as well as to the relevant customer's requirements. In particular the special winding form and the winding technique are treated. For each phase the most critical aspects and the relevant solutions are pointed out. Particular details about the technical solutions adopted for the impregnation and curing of the Double Pancake, which could not be performed inside an autoclave due to the huge dimension of the coil itself, are reported. Finally the methods used for the dimensional and electri...

The RPC LVL1 trigger system of the muon spectrometer of the ATLAS experiment at LHC

CERN Document Server

Aielli, G; Alviggi, M G; Biglietti, M; Bocci, V; Brambilla, Elena; Camarri, P; Canale, V; Caprio, M A; Cardarelli, R; Carlino, G; Cataldi, G; Chiodini, G; Conventi, F; De Asmundis, R; Della Pietra, M; Della Volpe, D; Di Ciaccio, A; Di Mattia, A; Di Simone, A; Falciano, S; Gorini, E; Grancagnolo, F; Iengo, P; Liberti, B; Luminari, L; Nisati, A; Pastore, F; Patricelli, S; Perrino, R; Petrolo, E; Primavera, M; Sekhniaidze, G; Spagnolo, S; Salamon, A; Santonico, R; Vari, R; Veneziano, Stefano

2004-01-01

The ATLAS Trigger System has been designed to reduce the LHC interaction rate of about 1 GHz to the foreseen storage rate of about 100 Hz. Three trigger levels are applied in order to fulfill such a requirement. A detailed simulation of the ATLAS experiment including the hardware components and the logic of the Level-1 Muon trigger in the barrel of the muon spectrometer has been performed. This simulation has been used not only to evaluate the performances of the system but also to optimize the trigger logic design. In the barrel of the muon spectrometer the trigger will be given by means of resistive plate chambers (RPCs) working in avalanche mode. Before being mounted on the experiment, accurate quality tests with cosmic rays are carried out on each RPC chamber using the test station facility of the INFN and University laboratory of Napoli. All working parameters are measured and the uniformity of the efficiency on the whole RPC surface is required. A summary of the Napoli cosmic rays tests, together with a...

ATLAS's inner detector installed in the heart of the experiment

CERN Multimedia

2006-01-01

The ATLAS collaboration recently celebrated a major engineering milestone, namely the transport and installation of the central part of the inner detector (ID-barrel) into the ATLAS detector. Right: Engineers and technicians work to carefully align and install the inner detector in the centre of ATLAS.Left: The crane used in the carefully coordinated effort by the ATLAS collaboration to lower down the fragile inner detector 100 metres underground to its new home. Many members of the collaboration gathered to witness this moment at Point 1. After years of design, construction and commissioning, the two outer detectors (TRT and SCT) of the inner detector barrel (ID-barrel) were moved from the SR1 cleanroom to the ATLAS cavern. The barrel was moved across the car park from Building 2175 to SX1. Although only a journey of about 100 metres, this required weeks of planning and some degree of luck as far as the weather was concerned. Special measures were in place to minimize shock and vibration during transportati...

The CMS Level-1 Trigger Barrel Track Finder

International Nuclear Information System (INIS)

Ero, J.; Wulz, C.; Evangelou, I.; Flouris, G.; Foudas, C.; Loukas, N.; Manthos, N.; Papadopoulos, I.; Paradas, E.; Guiducci, L.; Sotiropoulos, S.; Sphicas, P.; Triossi, A.

2016-01-01

The design and performance of the upgraded CMS Level-1 Trigger Barrel Muon Track Finder (BMTF) is presented. Monte Carlo simulation data as well as cosmic ray data from a CMS muon detector slice test have been used to study in detail the performance of the new track finder. The design architecture is based on twelve MP7 cards each of which uses a Xilinx Virtex-7 FPGA and can receive and transmit data at 10 Gbps from 72 input and 72 output fibers. According to the CMS Trigger Upgrade TDR the BMTF receives trigger primitive data which are computed using both RPC and DT data and transmits data from a number of muon candidates to the upgraded Global Muon Trigger. Results from detailed studies of comparisons between the BMTF algorithm results and the results of a C++ emulator are also presented. The new BMTF will be commissioned for data taking in 2016

Proposal for the renegotiation of a contract for the supply of eight coil casings for the barrel toroid magnet of the ATLAS detector

CERN Document Server

2001-01-01

This document concerns the renegotiation of a contract for the supply of eight coil casings for the Barrel Toroid Magnet of the ATLAS detector. The proposal for the award of a contract with ABB ENERTECH (CH) was presented to Finance Committee for information in September 1998 (CERN/FC/4089). In view of the developments outlined in this document, the Finance Committee is invited to agree to the renegotiation of a contract with ALSTOM SWITZERLAND (CH), for the supply of eight coil casings for the ATLAS Barrel Toroid Magnet for a total Ex-works price of 12 580 000 Swiss francs, subject to revision after 31 July 2001, with an option for an extra coil casing for an additional Ex-works price of 1 525 000 Swiss francs, subject to revision after 31 July 2001, bringing the total amount for the supply to 14 105 000 Swiss francs, subject to revision after 31 July 2001. The total amount of the contract, including transport to the integration site, will not exceed 14 490 000 Swiss francs, subject to revision after 31 July...

Commissioning the ATLAS Level-1 Central Trigger System

CERN Document Server

Sherman, Daniel

2010-01-01

The ATLAS Level-1 central trigger is a critical part of ATLAS operation. It receives the 40 MHz bunch clock from the LHC and distributes it to all sub-detectors. It initiates their read-out by forming the Level-1 Accept decision, which is based on information from the calorimeter and muon trigger processors and a variety of additional trigger inputs from detectors in the forward region. It also provides trigger summary information to the data acquisition system and the Level-2 trigger system. In this paper, we present the completion of the installed central trigger system, its performance during cosmic-ray data taking and the experience gained with triggering on the first LHC beams.

ATLAS Barrel Hadron Calorimeter: general manufacturing concepts for 300000 absorber plates mass production

International Nuclear Information System (INIS)

Alikov, B.A.; Budagov, Yu.A.; Bylinkin, P.M

1998-01-01

We summarize a 4-year (1994-1997) experience of design and research efforts which led us to the solution of 2 important tasks of a principal significance for precision assembly of one of major elements of ATLAS, - its Hadron Barrel Tile Calorimeter. These tasks were: - to develop the high tolerances (50-100 microns) technology for about 300000 units of calorimeter nuclear absorber plates mass production, - to choose the best manufacturer(s) able to satisfy shop drawings demands in a reasonable balance with some other significant criteria: production period, price acceptable geography location (transport expenses), available storage area and access ways, reliable quality control etc. For the best absorbers producers our final choice was the TATRA PLANT (Czech Republic) for 1.6 m long plates stamping (40800 units) with Argonne punching die and the MINSK TRACTOR PLANT (Belarus Republic) for smaller size plates stamping (about 240000 units). We exclude noticeable (more than 1% of the day production) tolerances violations by the specially developed QUALITY CONTROL Program

Clean tracks for ATLAS

CERN Multimedia

2006-01-01

First cosmic ray tracks in the integrated ATLAS barrel SCT and TRT tracking detectors. A snap-shot of a cosmic ray event seen in the different layers of both the SCT and TRT detectors. The ATLAS Inner Detector Integration Team celebrated a major success recently, when clean tracks of cosmic rays were detected in the completed semiconductor tracker (SCT) and transition radiation tracker (TRT) barrels. These tracking tests come just months after the successful insertion of the SCT into the TRT (See Bulletin 09/2006). The cosmic ray test is important for the experiment because, after 15 years of hard work, it is the last test performed on the fully assembled barrel before lowering it into the ATLAS cavern. The two trackers work together to provide millions of channels so that particles' tracks can be identified and measured with great accuracy. According to the team, the preliminary results were very encouraging. After first checks of noise levels in the final detectors, a critical goal was to study their re...

Towards a Level-1 Tracking Trigger for the ATLAS Experiment

CERN Document Server

De Santo, A; The ATLAS collaboration

2016-01-01

In preparation for the high-luminosity phase of the Large Hadron Collider, ATLAS is planning a trigger upgrade that will enable the experiment to use tracking information already at the first trigger level. This will provide enhanced background rejection power at trigger level while preserving much needed flexibility for the trigger system. The status and current plans for the new ATLAS Level-1 tracking trigger are presented.

ATLAS starts moving in

CERN Multimedia

2004-01-01

The first large active detector component was lowered into the ATLAS cavern on 1 March. It consisted of the 8 modules forming the lower part of the central barrel of the tile hadronic calorimeter. The work of assembling the barrel, which comprises 64 modules, started the following day.

ATLAS starts moving in

CERN Multimedia

Della Mussia, S

2004-01-01

The first large active detector component was lowered into the ATLAS cavern on 1st March. It consisted of the 8 modules forming the lower part of the central barrel of the tile hadronic calorimeter. The work of assembling the barrel, which comprises 64 modules, started the following day. Two road trailers each with 64 wheels, positioned side by side. This was the solution chosen to transport the lower part of the central barrel of ATLAS' tile hadronic calorimeter from Building 185 to the PX16 shaft at Point 1 (see Figure 1). The transportation, and then the installation of the component in the experimental cavern, which took place over three days were, to say the least, rather spectacular. On 25 February, the component, consisting of eight 6-metre modules, was loaded on to the trailers. The segment of the barrel was transported on a steel support so that it wouldn't move an inch during the journey. On 26 February, once all the necessary safety checks had been carried out, the convoy was able to leave Buildi...

ATLAS: last few metresfor the Calorimeter

CERN Multimedia

2005-01-01

On Friday 4th November, the ATLAS Barrel Calorimeter was moved from its assembly point at the side of the ATLAS cavern to the centre of the toroidal magnet system. The detector was finally aligned, to the precision of within a millimetre, on Wednesday 9th November. The ATLAS installation team, led by Tommi Nyman, after having positioned the Barrel Calorimeter in its final location in the ATLAS experimental cavern UX15. The Barrel Calorimeter which will absorb and measure the energy of photons, electrons and hadrons at the core of the ATLAS detector is 8.6 meters in diameter, 6.8 meters long, and weighs over 1600 Tonnes. It consists of two concentric cylindrical detector elements. The innermost comprises aluminium pressure vessels containing the liquid argon electromagnetic calorimeter and the solenoid magnet. The outermost is an assembly of 64 hadron tile calorimeter sectors. Assembled 18 meters away from its final position, the Barrel Calorimeter was relocated with the help of a railway, which allows the ...

Calibration for the ATLAS Level-1 Calorimeter-Trigger

International Nuclear Information System (INIS)

Foehlisch, F.

2007-01-01

This thesis describes developments and tests that are necessary to operate the Pre-Processor of the ATLAS Level-1 Calorimeter Trigger for data acquisition. The major tasks of Pre-Processor comprise the digitizing, time-alignment and the calibration of signals that come from the ATLAS calorimeter. Dedicated hardware has been developed that must be configured in order to fulfill these tasks. Software has been developed that implements the register-model of the Pre-Processor Modules and allows to set up the Pre-Processor. In order to configure the Pre-Processor in the context of an ATLAS run, user-settings and the results of calibration measurements are used to derive adequate settings for registers of the Pre-Processor. The procedures that allow to perform the required measurements and store the results into a database are demonstrated. Furthermore, tests that go along with the ATLAS installation are presented and results are shown. (orig.)

Calibration for the ATLAS Level-1 Calorimeter-Trigger

Energy Technology Data Exchange (ETDEWEB)

Foehlisch, F.

2007-12-19

This thesis describes developments and tests that are necessary to operate the Pre-Processor of the ATLAS Level-1 Calorimeter Trigger for data acquisition. The major tasks of Pre-Processor comprise the digitizing, time-alignment and the calibration of signals that come from the ATLAS calorimeter. Dedicated hardware has been developed that must be configured in order to fulfill these tasks. Software has been developed that implements the register-model of the Pre-Processor Modules and allows to set up the Pre-Processor. In order to configure the Pre-Processor in the context of an ATLAS run, user-settings and the results of calibration measurements are used to derive adequate settings for registers of the Pre-Processor. The procedures that allow to perform the required measurements and store the results into a database are demonstrated. Furthermore, tests that go along with the ATLAS installation are presented and results are shown. (orig.)

ATLAS ITk Strip Detector for High-Luminosity LHC

CERN Document Server

Kroll, Jiri; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High-Luminosity LHC that is scheduled for 2026. The expected peak instantaneous luminosity up to 7.5E34 per second and cm2 corresponding to approximately 200 inelastic proton-proton interactions per beam crossing, radiation damage at an integrated luminosity of 3000/fb and hadron fluencies over 1E16 1 MeV neutron equivalent per cm2, as well as fast hardware tracking capability that will bring Level-0 trigger rate of a few MHz down to a Level-1 trigger rate below 1 MHz require a replacement of existing Inner Detector by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The current prototyping phase, that is working with ITk Strip Detector consisting of a four-layer barrel and a forward region composed of six discs on each side of the barrel, has resulted in the ATLAS ITk Strip Detector Technical Design Report (TDR), which starts the pre-production readiness phase at the ...

ATLAS ITk Strip Detector for High-Luminosity LHC

CERN Document Server

Kroll, Jiri; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High-Luminosity LHC that is scheduled for 2026. The expected peak instantaneous luminosity up to $7.5\\times10^{34}\\;\\mathrm{cm}^{-2}\\mathrm{s}^{-1}$ corresponding to approximately 200 inelastic proton-proton interactions per beam crossing, radiation damage at an integrated luminosity of $3000\\;\\mathrm{fb}^{-1}$ and hadron fluencies over $2\\times10^{16}\\;\\mathrm{n}_{\\mathrm{eq}}/\\mathrm{cm}^{2}$, as well as fast hardware tracking capability that will bring Level-0 trigger rate of a few MHz down to a Level-1 trigger rate below 1 MHz require a replacement of existing Inner Detector by an all-silicon Inner Tracker with a pixel detector surrounded by a strip detector. The current prototyping phase, that is working with ITk Strip Detector consisting of a four-layer barrel and a forward region composed of six disks on each side of the barrel, has resulted in the ATLAS Inner Tracker Strip Detector Technical Design R...

Progress in the construction of the B0 model of the ATLAS Barrel Toroid magnet

CERN Document Server

Acerbi, E; Ambrosio, G; Baccaglioni, G; Broggi, F; Rossi, L; Sorbi, M; Volpini, G

2000-01-01

The ATLAS Barrel Toroid air-core magnet (BT) will be composed by 8 superconducting coils, each one 25 m long and 5 m wide. In order to validate the technologies and manufacturing processes, a smaller model (9 m long) of one BT coil, named B0, is now under construction. This paper presents a general overview of the B0 project status, with special regard to the components for which the LASA Lab. is responsible: (a) the aluminium-clad NbTi conductor; (b) the double coils winding and impregnation; (c) the components of the cryostat (vacuum chamber, thermal shield and suspension rod). (6 refs).

ATLAS rewards two Japanese suppliers of major detector components.

CERN Multimedia

Patrice Loïez

2002-01-01

The ATLAS supplier award in recognition of excellence has just been attributed to Kawasaki Heavy Industries, who produced the liquid-argon barrel cryostat. Kawasaki received its award in Hall 189 on the Meyrin site, where the cryostat is currently located. Toshiba Corporation's award for the superconducting central solenoid was presented two months ago at the Toshiba headquarters in Japan. Photo 01: P. Pailler, project leader for the ATLAS liquid-argon cryostats, addressing the Kawasaki delegation. Photo 04: H. Oberlack, project leader for the ATLAS liquid-argon system, addressing the Kawasaki delegation. Photo 11: P. Jenni (left), ATLAS Collaboration spokesperson, presenting the ATLAS supplier award for the barrel cryostat for the liquid-argon calorimeter to Mr. S. Nose, General Manager of Kawasaki Heavy Industries Ltd. Photo 18: J. Sondericker (left), liquid-argon barrel cryostat project engineer (BNL), presenting Mr. Nose (Kawasaki) an award from Brookhaven for the barrel cryostat for the ATLAS liquid-argo...

The Topological Processor for the future ATLAS Level-1 Trigger

CERN Document Server

Kahra, C; The ATLAS collaboration

2014-01-01

ATLAS is an experiment on the Large Hadron Collider (LHC), located at the European Organization for Nuclear Research (CERN) in Switzerland. By 2015 the LHC instantaneous luminosity will be increased from $10^{34}$ up to $3\\cdot 10^{34} \\mathrm{cm}^{-2} \\mathrm{s}^{-1}$. This places stringent operational and physical requirements on the ATLAS Trigger in order to reduce the 40MHz collision rate to a manageable event storage rate of 1kHz while at the same time, selecting those events that contain interesting physics events. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 100kHz and decision latency of less than $2.5 \\mu \\mathrm{s}$. It is composed of the Calorimeter Trigger, the Muon Trigger and the Central Trigger Processor (CTP). In 2014, there will be a new electronics module: the Topological Processor (L1Topo). The L1Topo will make it possible, for the first time, to use detailed information from subdetectors in a single Level-1 module. This allows the determi...

ATLAS Solenoid Integration

CERN Multimedia

Ruber, R

Last month the central solenoid was installed in the barrel cryostat, which it shares with the liquid argon calorimeter. Figure 1: Some members of the solenoid and liquid argon teams proudly pose in front of the barrel cryosat, complete with detector and magnet. Some two years ago the central solenoid arrived at CERN after being manufactured and tested in Japan. It was kept in storage until last October when it was finally moved to the barrel cryostat integration area. Here a position survey of the solenoid (with respect to the cryostat's inner warm vessel) was performed. Figure 2: The alignment survey by Dirk Mergelkuhl and Aude Wiart. (EST-SU) At the start of the New Year the solenoid was moved to the cryostat insertion stand. Figure 3: The solenoid on the insertion stand, with Akira Yamamoto the solenoid designer and project leader. Figure 4: Taka Kondo, ATLAS Japan spokesperson, and Shoichi Mizumaki, Toshiba project engineer for the ATLAS solenoid, celebrate the insertion. Aft...

Large-scale performance studies of the Resistive Plate Chamber fast tracker for the ATLAS 1st-level muon trigger

CERN Document Server

Cattani, G; The ATLAS collaboration

2009-01-01

In the ATLAS experiment, Resistive Plate Chambers provide the first-level muon trigger and bunch crossing identification over large area of the barrel region, as well as being used as a very fast 2D tracker. To achieve these goals a system of about ~4000 gas gaps operating in avalanche mode was built (resulting in a total readout surface of about 16000 m2 segmented into 350000 strips) and is now fully operational in the ATLAS pit, where its functionality has been widely tested up to now using cosmic rays. Such a large scale system allows to study the performance of RPCs (both from the point of view of gas gaps and readout electronics) with unprecedented sensitivity to rare effects, as well as providing the means to correlate (in a statistically significant way) characteristics at production sites with performance during operation. Calibrating such a system means fine tuning thousands of parameters (involving both front-end electronics and gap voltage), as well as constantly monitoring performance and environm...

L1Track: A fast Level 1 track trigger for the ATLAS high luminosity upgrade

International Nuclear Information System (INIS)

Cerri, Alessandro

2016-01-01

With the planned high-luminosity upgrade of the LHC (HL-LHC), the ATLAS detector will see its collision rate increase by approximately a factor of 5 with respect to the current LHC operation. The earliest hardware-based ATLAS trigger stage (“Level 1”) will have to provide a higher rejection factor in a more difficult environment: a new improved Level 1 trigger architecture is under study, which includes the possibility of extracting with low latency and high accuracy tracking information in time for the decision taking process. In this context, the feasibility of potential approaches aimed at providing low-latency high-quality tracking at Level 1 is discussed. - Highlights: • HL-LH requires highly performing event selection. • ATLAS is studying the implementation of tracking at the very first trigger level. • Low latency and high-quality seem to be achievable with dedicated hardware and adequate detector readout architecture.

Digital Filter Performance for the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Hadley, D R; The ATLAS collaboration

2010-01-01

The ATLAS Level-1 Calorimeter Trigger is a hardware-based system designed to identify high-pT jets, electron/photon and tau candidates, and to measure total and missing ET in the ATLAS Liquid Argon and Tile calorimeters. It is a pipelined processor system, with a new set of inputs being evaluated every 25ns. The overall trigger decision has a latency budget of 2µs, including all transmission delays. The calorimeter trigger uses about 7200 reduced granularity analogue signals, which are first digitized at the 40 MHz LHC bunch-crossing frequency, before being passed to a digital Finite Impulse Response (FIR) filter. Due to latency and chip real-estate constraints, only a simple 5-element filter with limited precision can be used. Nevertheless this filter achieves a significant reduction in noise, along with improving the bunch-crossing assignment and energy resolution for small signals. The context in which digital filters are used for the ATLAS Level-1 Calorimeter Trigger will be presented, before describing ...

First ATLAS Events Recorded Underground

CERN Multimedia

Teuscher, R

As reported in the CERN Bulletin, Issue No.30-31, 25 July 2005 The ATLAS barrel Tile calorimeter has recorded its first events underground using a cosmic ray trigger, as part of the detector commissioning programme. This is not a simulation! A cosmic ray muon recorded by the barrel Tile calorimeter of ATLAS on 21 June 2005 at 18:30. The calorimeter has three layers and a pointing geometry. The light trapezoids represent the energy deposited in the tiles of the calorimeter depicted as a thick disk. On the evening of June 21, the ATLAS detector, now being installed in the underground experimental hall UX15, reached an important psychological milestone: the barrel Tile calorimeter recorded the first cosmic ray events in the underground cavern. An estimated million cosmic muons enter the ATLAS cavern every 3 minutes, and the ATLAS team decided to make good use of some of them for the commissioning of the detector. Although only 8 of the 128 calorimeter slices ('superdrawers') were included in the trigg...

ATLAS detector records its first curved muon

CERN Multimedia

2007-01-01

The barrel muon spectrometer of the ATLAS detector has acquired its first cosmic event in a magnetic field produced by the barrel toroid magnet. This was an important test of the chambers in their final configurations, and marked the first triggering and measurement of curved cosmic ray muons in ATLAS.

The Digital Algorithm Processors for the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Silverstein, S

2010-01-01

The ATLAS Level-1 Calorimeter Trigger identifies high-ET jets, electrons/photons and hadrons and measures total and missing transverse energy in proton-proton collisions at the Large Hadron Collider. Two subsystems – the Jet/Energy-sum Processor (JEP) and the Cluster Processor(CP) – process data from every crossing, and report feature multiplicities and energy sums to the ATLAS Central Trigger Processor, which produces a Level-1 Accept decision. Locations and types of identified features are read out to the Level-2 Trigger as regions-of-interest, and quality-monitoring information is read out to the ATLAS data acquisition system. The JEP and CP subsystems share a great deal of common infrastructure, including a custom backplane, several common hardware modules, and readout hardware. Some of the common modules use FPGAs with selectable firmware configurations based on the location in the system. This approach saved substantial development effort and provided a uniform model for software development. We pre...

The Digital Algorithm Processors for the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Silverstein, S; The ATLAS collaboration

2009-01-01

The ATLAS Level-1 Calorimeter Trigger identifies high-ET jets, electrons/photons and hadrons and measures total and missing transverse energy in proton-proton collisions at the Large Hadron Collider. Two subsystems – the Jet/Energy-sum Processor (JEP) and the Cluster Processor(CP) – process data from every crossing, and report feature multiplicities and energy sums to the ATLAS Central Trigger Processor, which produces a Level-1 Accept decision. Locations and types of identified features are read out to the Level-2 Trigger as regions-of-interest, and quality-monitoring information is read out to the ATLAS data acquisition system. The JEP and CP subsystems share a great deal of common infrastructure, including a custom backplane, several common hardware modules, and readout hardware. Some of the common modules use FPGAs with selectable firmware configurations based on the location in the system. This approach saved substantial development effort and provided a uniform model for software development. We pre...

The ATLAS Level-1 Trigger Timing Setup

CERN Document Server

Spiwoks, R; Ellis, Nick; Farthouat, P; Gällnö, P; Haller, J; Krasznahorkay, A; Maeno, T; Pauly, T; Pessoa-Lima, H; Resurreccion-Arcas, I; Schuler, G; De Seixas, J M; Torga-Teixeira, R; Wengler, T

2005-01-01

The ATLAS detector at CERN's LHC will be exposed to proton-proton collisions at a bunch-crossing rate of 40 MHz. In order to reduce the data rate, a three-level trigger system selects potentially interesting physics. The first trigger level is implemented in electronics and firmware. It aims at reducing the output rate to less than 100 kHz. The Central Trigger Processor combines information from the calorimeter and muon trigger processors and makes the final Level-1-Accept decision. It is a central element in the timing setup of the experiment. Three aspects are considered in this article: the timing setup with respect to the Level-1 trigger, with respect to the expriment, and with respect to the world.

Upgrade of ATLAS ITk Pixel Detector

CERN Document Server

Huegging, Fabian; The ATLAS collaboration

2017-01-01

The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current inner detector will be replaced with an entirely-silicon inner tracker (ITk) which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors and low mass global and local support structures. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the ITk ATLAS Pixel detector developments as well as different layout options will be reviewed.

Digital Filtering Performance in the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Hadley, D R; The ATLAS collaboration

2010-01-01

The ATLAS Level-1 Calorimeter Trigger is a hardware-based system designed to identify high-pT jets, elec- tron/photon and tau candidates, and to measure total and missing ET in the ATLAS Liquid Argon and Tile calorimeters. It is a pipelined processor system, with a new set of inputs being evaluated every 25ns. The overall trigger decision has a latency budget of 2µs, including all transmission delays. The calorimeter trigger uses about 7200 reduced granularity analogue signals, which are first digitized at the 40 MHz LHC bunch-crossing frequency, before being passed to a digital Finite Impulse Re- sponse (FIR) filter. Due to latency and chip real-estate constraints, only a simple 5-element filter with limited precision can be used. Nevertheless, this filter achieves a significant reduction in noise, along with improving the bunch-crossing assignment and energy resolution for small signals. The context in which digital filters are used for the ATLAS Level-1 Calorimeter Trigger is presented, before descr...

Experimental study of the effect of hadron shower leakage on the energy response and resolution of ATLAS hadron barrel prototype calorimeter

International Nuclear Information System (INIS)

Budagov, Yu.A.; Vinogradov, V.B.; Kul'chitskij, Yu.A.; Rumyantsev, V.S.; Bogush, A.A.; Karapetyan, G.; Nessi, M.

1996-01-01

The hadronic shower longitudinal and lateral leakages and their effect on the pion response and energy resolution of ATLAS iron-scintillator barrel hadron prototype calorimeter have been investigated. The results are based on 100 GeV pion beam data at incidence angle Θ=10 deg. The fraction of the energy leaking out at the back of this calorimeter amounts to 1.8 % and agrees with the one for a conventional iron-scintillator calorimeter. Unexpected behaviour of the energy resolution as a function of leakage is observed: 6 % lateral leakage leads to 18 % improving of energy resolution in compare with the showers without leakage. 22 refs., 13 figs., 4 tabs

ATLAS' inner silicon tracker on track for completion

CERN Multimedia

2005-01-01

Last week, the team working at the SR1 facility on the inner detector of the ATLAS experiment reached a project milestone after the delivery of the last Semi-conductor Tracker (SCT) barrel to CERN. The third barrel before its insertion into the support structure.The insertion of a completed barrel to its support structure is one of the highlights of the assembly and test sequence of the SCT in SR1. The inner detector will eventually sit in the 2 teslas magnetic field of the ATLAS solenoid, tracking charged particles from proton-proton collisions at the centre of ATLAS. The particles will be measured by a pixel detector (consisting of 3 pixel layers), an SCT (4 silicon strip layers) and a transition radiation tracker (TRT) (consisting of more than 52,000 straw tubes - see Bulletin 14/2005). The SCT has a silicon surface area of 61m2 with about 6 million operational channels so that all tracks can be identified and precisely measured. During 2004 a team of physicists, engineers, and technicians from several...

Operation of the Upgraded ATLAS Level-1 Central Trigger System

CERN Document Server

Glatzer, Julian Maximilian Volker; The ATLAS collaboration

2015-01-01

The ATLAS Level-1 Central Trigger (L1CT) system is a central part of ATLAS data-taking and has undergone a major upgrade for Run 2 of the LHC, in order to cope with the expected increase of instantaneous luminosity of a factor of 2 with respect to Run 1. The upgraded hardware offers more flexibility in the trigger decisions due to the double amount of trigger inputs and usable trigger channels. It also provides an interface to the new topological trigger system. Operationally - particularly useful for commissioning, calibration and test runs - it allows concurrent running of up to 3 different sub-detector combinations. In this contribution, we give an overview of the operational software framework of the L1CT system with particular emphasis of the configuration, controls and monitoring aspects. The software framework allows a consistent configuration with respect to the ATLAS experiment and the LHC machine, upstream and downstream trigger processors, and the data acquisition. Trigger and dead-time rates are m...

The ATLAS Level-1 Trigger System with 13TeV nominal LHC collisions

CERN Document Server

Helary, Louis; The ATLAS collaboration

2017-01-01

The Level-1 (L1) Trigger system of the ATLAS experiment at CERN's Large Hadron Collider (LHC) plays a key role in the ATLAS detector data-taking. It is a hardware system that selects in real time events containing physics-motivated signatures. Selection is purely based on calorimetry energy depositions and hits in the muon chambers consistent with muon candidates. The L1 Trigger system has been upgraded to cope with the more challenging run-II LHC beam conditions, including increased centre-of-mass energy, increased instantaneous luminosity and higher levels of pileup. This talk summarises the improvements, commissioning and performance of the L1 ATLAS Trigger for the LHC run-II data period. The acceptance of muon triggers has been improved by increasing the hermiticity of the muon spectrometer. New strategies to obtain a better muon trigger signal purity were designed for certain geometrically difficult transition regions by using the ATLAS hadronic calorimeter. Algorithms to reduce noise spikes in muon trig...

ATLAS Barrel Toroid magnet reached nominal field

CERN Multimedia

2006-01-01

 On 9 November the barrel toroid magnet reached its nominal field of 4 teslas, with an electrical current of 21 000 amperes (21 kA) passing through the eight superconducting coils as shown on this graph

ATLAS Level-1 Topological Trigger

CERN Document Server

Zheng, Daniel; The ATLAS collaboration

2018-01-01

The ATLAS experiment has introduced and recently commissioned a completely new hardware sub-system of its first-level trigger: the topological processor (L1Topo). L1Topo consist of two AdvancedTCA blades mounting state-of-the-art FPGA processors, providing high input bandwidth (up to 4 Gb/s) and low latency data processing (200 ns). L1Topo is able to select collision events by applying kinematic and topological requirements on candidate objects (energy clusters, jets, and muons) measured by calorimeters and muon sub-detectors. Results from data recorded using the L1Topo trigger will be presented. These results demonstrate a significantly improved background event rejection, thus allowing for a rate reduction without efficiency loss. This improvement has been shown for several physics processes leading to low-pT leptons, including H->tau tau and J/Psi->mu mu. In addition to describing the L1Topo trigger system, we will discuss the use of an accurate L1Topo simulation as a powerful tool to validate and optimize...

The data path of the ATLAS level-1 calorimeter trigger preprocessor

Energy Technology Data Exchange (ETDEWEB)

Andrei, George Victor

2010-10-27

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger provides digital values of transverse energy in real-time to the subsequent object-finding processors. The input comprises more than 7000 analogue signals of reduced granularity from the calorimeters of the ATLAS detector. The Level-1 trigger decision must be verified. For this, the PreProcessor transmits copies of the real-time digital data to the Data Acquisition (DAQ) system. In addition, the PreProcessor system provides a standard VMEbus interface to the computing infrastructure of the experiment, on which configuration data is loaded and control or monitoring data are read out. A dedicated system that ensures both the transfer of event data to storage in ATLAS and the data transfer over the VME was implemented on the 124 modules of the PreProcessor system in the form of a ''Readout Manager''. The ''Field Programmable Gate Array'' (FPGA) is located on each module. The rst part of this work describes the algorithms developed to meet the functionality of the Readout Manager. The second part deals with the tests that were carried out to ensure the proper functionality of the modules before they were installed at CERN in the ATLAS cavern. (orig.)

The data path of the ATLAS level-1 calorimeter trigger preprocessor

International Nuclear Information System (INIS)

Andrei, George Victor

2010-01-01

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger provides digital values of transverse energy in real-time to the subsequent object-finding processors. The input comprises more than 7000 analogue signals of reduced granularity from the calorimeters of the ATLAS detector. The Level-1 trigger decision must be verified. For this, the PreProcessor transmits copies of the real-time digital data to the Data Acquisition (DAQ) system. In addition, the PreProcessor system provides a standard VMEbus interface to the computing infrastructure of the experiment, on which configuration data is loaded and control or monitoring data are read out. A dedicated system that ensures both the transfer of event data to storage in ATLAS and the data transfer over the VME was implemented on the 124 modules of the PreProcessor system in the form of a ''Readout Manager''. The ''Field Programmable Gate Array'' (FPGA) is located on each module. The rst part of this work describes the algorithms developed to meet the functionality of the Readout Manager. The second part deals with the tests that were carried out to ensure the proper functionality of the modules before they were installed at CERN in the ATLAS cavern. (orig.)

The data path of the ATLAS level-1 calorimeter trigger preprocessor

Energy Technology Data Exchange (ETDEWEB)

Andrei, George Victor

2010-10-27

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger provides digital values of transverse energy in real-time to the subsequent object-finding processors. The input comprises more than 7000 analogue signals of reduced granularity from the calorimeters of the ATLAS detector. The Level-1 trigger decision must be verified. For this, the PreProcessor transmits copies of the real-time digital data to the Data Acquisition (DAQ) system. In addition, the PreProcessor system provides a standard VMEbus interface to the computing infrastructure of the experiment, on which configuration data is loaded and control or monitoring data are read out. A dedicated system that ensures both the transfer of event data to storage in ATLAS and the data transfer over the VME was implemented on the 124 modules of the PreProcessor system in the form of a ''Readout Manager''. The ''Field Programmable Gate Array'' (FPGA) is located on each module. The rst part of this work describes the algorithms developed to meet the functionality of the Readout Manager. The second part deals with the tests that were carried out to ensure the proper functionality of the modules before they were installed at CERN in the ATLAS cavern. (orig.)

Overview and performance of the ATLAS Level-1 Topological Trigger

CERN Document Server

Damp, Johannes Frederic; The ATLAS collaboration

2018-01-01

In 2017 the LHC provided proton-proton collisions to the ATLAS experiment with high luminosity (up to 2.06x10^34), placing stringent operational and physical requirements on the ATLAS trigger system in order to reduce the 40 MHz collision rate to a manageable event storage rate of 1 kHz, while not rejecting interesting physics events. The Level-1 trigger is the first rate-reducing step in the ATLAS trigger system with an output rate of 100 kHz and decision latency of less than 2.5 μs. An important role is played by its newly commissioned component: the L1 topological trigger (L1Topo). This innovative system consists of two blades designed in AdvancedTCA form factor, mounting four individual state-of-the-art processors, and providing high input bandwidth and low latency data processing. Up to 128 topological trigger algorithms can be implemented to select interesting events by applying kinematic and angular requirements on electromagnetic clusters, jets, muons and total energy. This results in a significantly...

Celebrating the Barrel Toroid commissioning

CERN Multimedia

Peter Jenni

ATLAS invited Funding Agency representatives and Laboratory Heads directly related to the funding and construction of the Barrel Toroid for a small ceremony on 13th December 2006 at Point 1, in order to mark the successful first full excitation of the BT (see last eNews). On that date, which was during the December CERN Council week, several of the Funding Agency Heads or their representatives could be present, representing CEA France, INFN Italy, BMBF Germany, Spain, Sweden, Switzerland, Russia, JINR Dubna and CERN. Speeches were delivered by the ATLAS spokesperson Peter Jenni thanking the Funding Partners in the name of the Collaboration, by Magnet Project Leader Herman ten Kate tracing the BT construction history, and by the CERN Director-General Robert Aymar congratulating all those who have contributed to the successful project. Herman ten Kate addressing the delegates. The text of the introductory address by Peter Jenni is reproduced here. "It is a great pleasure for me to welcome you all here...

The ATLAS Level-1 Central Trigger Processor (CTP)

CERN Document Server

Spiwoks, Ralf; Ellis, Nick; Farthouat, P; Gällnö, P; Haller, J; Krasznahorkay, A; Maeno, T; Pauly, T; Pessoa-Lima, H; Resurreccion-Arcas, I; Schuler, G; De Seixas, J M; Torga-Teixeira, R; Wengler, T

2005-01-01

The ATLAS Level-1 Central Trigger Processor (CTP) combines information from calorimeter and muon trigger processors and makes the final Level-1 Accept (L1A) decision on the basis of lists of selection criteria (trigger menus). In addition to the event-selection decision, the CTP also provides trigger summary information to the Level-2 trigger and the data acquisition system. It further provides accumulated and bunch-by-bunch scaler data for monitoring of the trigger, detector and beam conditions. The CTP is presented and results are shown from tests with the calorimeter adn muon trigger processors connected to detectors in a particle beam, as well as from stand-alone full-system tests in the laboratory which were used to validate the CTP.

Upgrade of the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Wessels, M; The ATLAS collaboration

2014-01-01

The Level-1 Calorimeter Trigger (L1Calo) of the ATLAS experiment has been operating well since the start of LHC data taking, and played a major role in the Higgs boson discovery. To face the new challenges posed by the upcoming increases of the LHC proton beam energy and luminosity, a series of upgrades is planned for L1Calo. The initial upgrade phase in 2013-14 includes substantial improvements to the analogue and digital signal processing to allow more sophisticated digital filters for energy and timing measurement, as well as compensate for pile-up and baseline shifting effects. Two existing digital algorithm processor subsystems will receive substantial hardware and firmware upgrades to increase the real-time data path bandwidth, allowing topological information to be transmitted and processed at Level-1. An entirely new subsystem, the Level-1 Topological Processor, will receive real-time data from both the upgraded L1Calo and Level-1 Muon Trigger to perform trigger algorithms based on entire event topolo...

Study of energy response and resolution of the ATLAS barrel calorimeter to hadrons of energies from 20 to 350 GeV

Energy Technology Data Exchange (ETDEWEB)

Abat, E [Bogazici University, Faculty of Sciences, Department of Physics, TR - 80815 Bebek-Istanbul (Turkey); Abdallah, J M [Institut de Fisica d' Altes Energies, IFAE, Universitat Autonoma de Barcelona, Edifici Cn, ES - 08193 Bellaterra (Barcelona) (Spain); Addy, T N [Hampton University, Department of Physics, Hampton, VA 23668 (United States); Adragna, P [Queen Mary, University of London, Mile End Road, E1 4NS London (United Kingdom); Aharrouche, M [Universitaet Mainz, Institut fuer Physik, Staudinger Weg 7, DE 55099 (Germany); Ahmad, A [Department of Physics and Astronomy, Stony Brook, NY 11794-3800 (United States); Akesson, T P.A. [Lunds Universitet, Naturvetenskapliga Fakulteten, Fysiska Institutionen, Box 118, SE - 221 00, Lund (Sweden); Aleksa, M [European Laboratory for Particle Physics (CERN), CH-1211 Geneva 23 (Switzerland); Alexa, C [National Institute of Physics and Nuclear Engineering (Bucharest -IFIN-HH), P.O. Box MG-6, R-077125 Bucharest (Romania); Anderson, K [University of Chicago, Enrico Fermi Institute, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Anghinolfi, F [European Laboratory for Particle Physics (CERN), CH-1211 Geneva 23 (Switzerland); Antonaki, A; Arabidze, G [University of Athens, Nuclear and Particle Physics Department of Physics, Panepistimiopouli Zografou, GR 15771 Athens (Greece); Arik, E [Bogazici University, Faculty of Sciences, Department of Physics, TR - 80815 Bebek-Istanbul (Turkey); Baker, O K [Yale University, Department of Physics, PO Box 208121, New Haven, CT 06520-8121 (United States); Banfi, D [Universita di Milano, Dipartimento di Fisica and INFN, via Celoria 16, IT - 20133 Milano (Italy); Baron, S [European Laboratory for Particle Physics (CERN), CH-1211 Geneva 23 (Switzerland); Beck, H P [University of Bern, Laboratory for High Energy Physics, Sidlerstrasse 5, CH - 3012 Bern (Switzerland)

2010-09-21

A fully instrumented slice of the ATLAS detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. In this paper, the results of the measurements of the response of the barrel calorimeter to hadrons with energies in the range 20-350 GeV and beam impact points and angles corresponding to pseudo-rapidity values in the range 0.2-0.65 are reported. The results are compared to the predictions of a simulation program using the Geant 4 toolkit.

Study of energy response and resolution of the ATLAS barrel calorimeter to hadrons of energies from 20 to 350 GeV

International Nuclear Information System (INIS)

Abat, E.; Abdallah, J.M.; Addy, T.N.; Adragna, P.; Aharrouche, M.; Ahmad, A.; Akesson, T.P.A.; Aleksa, M.; Alexa, C.; Anderson, K.; Anghinolfi, F.; Antonaki, A.; Arabidze, G.; Arik, E.; Baker, O.K.; Banfi, D.; Baron, S.; Beck, H.P.

2010-01-01

A fully instrumented slice of the ATLAS detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. In this paper, the results of the measurements of the response of the barrel calorimeter to hadrons with energies in the range 20-350 GeV and beam impact points and angles corresponding to pseudo-rapidity values in the range 0.2-0.65 are reported. The results are compared to the predictions of a simulation program using the Geant 4 toolkit.

ATLAS Award for Difficult Task

CERN Multimedia

2004-01-01

Two Russian companies were honoured with an ATLAS Award, for supply of the ATLAS Inner Detector barrel support structure elements, last week. On 23 March the Russian company ORPE Technologiya and its subcontractor, RSP Khrunitchev, were jointly presented with an ATLAS Supplier Award. Since 1998, ORPE Technologiya has been actively involved in the development of the carbon-fibre reinforced plastic elements of the ATLAS Inner Detector barrel support structure. After three years of joint research and development, CERN and ORPE Technologiya launched the manufacturing contract. It had a tight delivery schedule and very demanding specifications in terms of mechanical tolerance and stability. The contract was successfully completed with the arrival of the last element of the structure at CERN on 8 January 2004. The delivery of this key component of the Inner Detector deserves an ATLAS Award given the difficulty of manufacturing the end-frames, which very few companies in the world would have been able to do at an ...

Validation Tools for ATLAS Muon Spectrometer Commissioning

International Nuclear Information System (INIS)

Benekos, N.Chr.; Dedes, G.; Laporte, J.F.; Nicolaidou, R.; Ouraou, A.

2008-01-01

The ATLAS Muon Spectrometer (MS), currently being installed at CERN, is designed to measure final state muons of 14 TeV proton-proton interactions at the Large Hadron Collider (LHC) with a good momentum resolution of 2-3% at 10-100 GeV/c and 10% at 1 TeV, taking into account the high level background enviroment, the inhomogeneous magnetic field, and the large size of the apparatus (24 m diameter by 44 m length). The MS layout of the ATLAS detector is made of a large toroidal magnet, arrays of high-pressure drift tubes for precise tracking and dedicated fast detectors for the first-level trigger, and is organized in eight Large and eight Small sectors. All the detectors of the barrel toroid have been installed and the commissioning has started with cosmic rays. In order to validate the MS performance using cosmic events, a Muon Commissioning Validation package has been developed and its results are presented in this paper. Integration with the rest of the ATLAS sub-detectors is now being done in the ATLAS cavern

ATLAS Level-1 Calorimeter Trigger: Initial Timing and Energy Calibration

CERN Document Server

Childers, J T; The ATLAS collaboration

2010-01-01

The ATLAS Level-1 Calorimeter Trigger identifies high-pT objects in the Liquid Argon and Tile Calorimeters with a fixed latency of ~2.0 µs using a hardware-based, pipelined system built with custom electronics. The Preprocessor Module conditions and digitizes about 7200 pre-summed analogue signals from the calorimeters at the LHC bunch-crossing frequency of 40 MHz, and performs bunch-crossing identification (BCID) and deposited energy measurement for each input signal. This information is passed to further processors for object classification and total energy calculation, and the results used to make the Level-1 trigger decision for the ATLAS detector. The BCID and energy measurement in the trigger depend on precise timing adjustment to achieve correct sampling of the input signal peak. Test pulses from the calorimeters were analysed to derive the initial timing and energy calibration, and first data from the LHC restart in autumn 2009 and early 2010 were used for validation and further optimization. The res...

First full-size ATLAS barrel toroid coil successfully tested up to 22 kA at 4 T

CERN Document Server

Dudarev, A; Benoit, P; Berriaud, C P; Broggi, F; Deront, L; Foussat, A; Junker, S; ten Kate, H H J; Kopeykin, N; Olesen, G; Olyunin, A; Pengo, R; Rabbers, J J; Ravat, S; Rey, J M; Sbrissa, E; Shugaev, I; Stepanov, V; Védrine, P; Volpini, Giovanni

2005-01-01

The Superconducting Barrel Toroid is providing (together with the two End-Cap Toroids not presented here) the magnetic field for the muon detectors in the ATLAS Experiment at the LHC at CERN. The toroid with outer dimensions of 25 m length and 20 m diameter, is built up from 8 identical racetrack coils. The coils with 120 turns each are wound with an aluminum stabilized NbTi conductor and operate at 20.5 kA at 3.9 T local field in the windings and is conduction cooled at 4.8 K by circulating forced flow helium in cooling tubes attached to the cold mass. The 8 coils of 25 m * 5 m are presently under construction and the first coils have already been fully integrated and tested. Meanwhile the assembly of the toroid 100 m underground in the ATLAS cavern at CERN has started. The 8 coils are individually tested on surface before installation. In this paper the test of the first coil, unique in size and manufacturing technology, is described in detail and the results are compared to the previous experience with the...

Upgrade of the ATLAS Level-1 Trigger with event topology information

CERN Document Server

Simioni, Eduard; The ATLAS collaboration; Bauss, B; Büscher, V; Jakobi, K; Kaluza, A; Kahra, C; Reiss, A; Schäffer, J; Schulte, A; Simon, M; Tapprogge, S; Vogel, A; Zinser, M; Palka, M

2015-01-01

The Large Hadron Collider (LHC) in 2015 will collide proton beams with increased luminosity from \\unit{10^{34}} up to \\unit{3 \\times 10^{34}cm^{-2}s^{-1}}. ATLAS is an LHC experiment designed to measure decay properties of high energetic particles produced in the protons collisions. The higher luminosity places stringent operational and physical requirements on the ATLAS Trigger in order to reduce the 40MHz collision rate to a manageable event storage rate of 1kHz while at the same time, selecting those events with valuable physics meaning. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 100kHz and decision latency of less than 2.5$\\mu s$. It is composed of the Calorimeter Trigger (L1Calo), the Muon Trigger (L1Muon) and the Central Trigger Processor (CTP). In 2014, there will be a new electronics element in the chain: the Topological Processor System (L1Topo system).\\\\ The L1Topo system consist of a single AdvancedTCA shelf equipped with three L1Topo processor ...

Mechanical behavior of the ATLAS B0 model coil

CERN Document Server

Foussat, A; Acerbi, E; Alessandria, F; Berthier, R; Broggi, F; Daël, A; Dudarev, A; Mayri, C; Miele, P; Reytier, M; Rossi, L; Sorbi, M; Sun, Z; ten Kate, H H J; Vanenkov, I; Volpini, G

2002-01-01

The ATLAS B0 model coil has been developed and constructed to verify the design parameters and the manufacture techniques of the Barrel Toroid coils (BT) that are under construction for the ATLAS Detector. Essential for successful operation is the mechanical behavior of the superconducting coil and its support structure. In the ATLAS magnet test facility, a magnetic mirror is used to reproduce in the model coil the electromagnetic forces of the BT coils when assembled in the final Barrel Toroid magnet system. The model coil is extensively equipped with mechanical instrumentation to monitor stresses and force levels as well as contraction during a cooling down and excitation up to nominal current. The installed set up of strain gauges, position sensors and capacitive force transducers is presented. Moreover the first mechanical results in terms of expected main stress, strain and deformation values are presented based on detailed mechanical analysis of the design. (7 refs).

2001, the ATLAS Cryostat Odyssey

CERN Multimedia

2001-01-01

After a journey of several thousand kilometres, over sea and land, by canal and highway, the cryogenics barrel of the ATLAS electromagnetic calorimeter finally arrived at CERN last week. Installed in Hall 180, the cryogenics barrel of the ATLAS electromagnetic calorimeter will be fitted out to take the central superconducting solenoid and the electromagnetic calorimeter. On Monday 2 July, different French police units and EDF officials were once again keeping careful watch around the hairpin bends of the road twisting down from the Col de la Faucille: a special load weighing 100 tonnes, 7 metres high, 5.8 metres wide and 7.2 metres long was being brought down into the Pays de Gex to the Meyrin site of CERN. This time the destination was the ATLAS experiment. A huge blue tarpaulin cover concealed the cryogenics barrel of the experiment's liquid argon electromagnetic calorimeter. The cryostat consists of a vacuum chamber, a cylinder that is 5.5 metres in diameter, 7 metres long, and a concentric cold chamber ...

Cosmic Ray Data in TRT Barrel

CERN Multimedia

M. Hance

"I had a great day in August when I went into SR1," said Daniel Froidevaux, former project leader of the ATLAS Transition Radiation Tracker, "not only had all SCT barrels arrived at CERN, but there were cosmic ray tracks seen in the TRT!" Daniel's excitement was mirrored by the rest of the TRT collaboration when, on July 29, the first cosmic ray tracks were seen in the barrel. Along with many others in the community, Daniel was quick to point out that this is the cumulative result of years of R&D, test beam work, and an intense installation and integration schedule. Indeed, the cosmic ray readout is only possible through the coordination of many efforts, from detector mechanics to module assembly, power and high voltage control, cooling, gas systems, electronics and cabling, data acquisition, and monitoring. "Many people have worked very hard on the the TRT, some of them for more than 10 years," said Brig Williams, the leader of the UPenn group responsible for much of the TRT front end electronics. He ...

Upgrade of the ATLAS Level-1 trigger with an FPGA based Topological Processor

CERN Document Server

Caputo, R; The ATLAS collaboration; Buescher, V; Degele, R; Kiese, P; Maldaner, S; Reiss, A; Schaefer, U; Simioni, E; Tapprogge, S; Urrejola, P

2013-01-01

The ATLAS experiment is located at the European Centre for Nuclear Research (CERN) in Switzerland. It is designed to measure decay properties of high energetic particles produced in the protons collisions at the Large Hadron Collider (LHC). The LHC has a proton collision at a frequency of 40 MHz, and thus requires a trigger system to efficiently select events down to a manageable event storage rate of about 400Hz. Event triggering is therefore one of the extraordinary challenges faced by the ATLAS detector. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 75kHz and decision latency of less than 2.5$\\mu$s. It is primarily composed of the Calorimeter Trigger, Muon Trigger, the Central Trigger Processor (CTP). Due to the increase in the LHC instantaneous luminosity up to 3$\\times$10$^{34}$ cm$^{−2}$ s$^{−1}$ from 2015 onwards, a new element will be included in the Level-1 Trigger scheme: the Topological Processor (L1Topo). The L1Topo receives data in a dedicate...

Operation and performance of the ATLAS Level-1 Calorimeter and Level-1 Topological Triggers in Run 2 at the LHC

CERN Document Server

Whalen, Kate; The ATLAS collaboration

2017-01-01

In Run 2 at CERN's Large Hadron Collider, the ATLAS detector uses a two-level trigger system to reduce the event rate from the nominal collision rate of 40 MHz to the event storage rate of 1 kHz, while preserving interesting physics events. The first step of the trigger system, Level-1, reduces the event rate to 100 kHz with a latency of less than 2.5 μs. One component of this system is the Level-1 Calorimeter Trigger (L1Calo), which uses coarse-granularity information from the electromagnetic and hadronic calorimeters to identify regions of interest corresponding to electrons, photons, taus, jets, and large amounts of transverse energy and missing transverse energy. In this talk, we will discuss the improved performance of the L1Calo system in the challenging, high-luminosity conditions provided by the LHC in Run 2. As the LHC exceeds its design luminosity, it is becoming even more critical to reduce event rates while preserving physics. A new feature of the ATLAS trigger system for Run 2 is the Level-1 Top...

ATLAS ITk Pixel detector

CERN Document Server

Gemme, Claudia; The ATLAS collaboration

2016-01-01

The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

ATLAS RPC commissioning status and cosmic ray test results

CERN Document Server

Bianco, Michele

2009-01-01

The muon trigger system of the ATLAS experiment consists of several sub-systems and each of them need to be tested and certified before LHC operation. In the barrel region Resistive Plate Chambers are employed. RPC detector and its level-1 trigger electronics are designed to detect and select high momentum muons with high time resolution and good tracking capability for a total surface of about 4000 m2. The commissioning phase provided an unique opportunity to demonstrate, before LHC start-up, the functionality of the muon trigger components such as detector chambers, level-1 trigger electronics, detector slow control system, data acquisition chain, software and computing. We present the status of ATLAS RPC detector, the problems met during the commissioning and the solutions found and, finally, its performances as obtained by acquiring cosmic rays.

Precision Timing of the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Davygora, Yuriy; The ATLAS collaboration

2012-01-01

The ATLAS Level-1 Calorimeter Trigger is one of the main elements of the first-stage online selection of LHC collision events measured at the ATLAS experiment. Using 7168 pre-summed trigger tower signals from the Liquid Argon and Tile calorimeters as input, the hardware-based system identifies high-pT objects and determines the total and missing transverse energy sums within a fixed latency of 2.5 us. The Preprocessor system digitizes the analogue calorimeter signals at the LHC bunch-crossing frequency of 40MHz and provides bunch-crossing identification and energy measurement. Prerequisite for high stability and accuracy of this procedure is a timing synchronization at the nanosecond level of the signals which belong to the same collision event. The synchronization of the trigger tower signals was first established in the analysis of beam splash events in November 2009 and then refined and sustained with data from proton-proton collisions at a centre-of-mass energy of 7TeV, recorded at the LHC in 2010 and 201...

The Topological Processor for the future ATLAS Level-1 Trigger: from design to commissioning

CERN Document Server

Simioni, E; The ATLAS collaboration

2014-01-01

The ATLAS experiment is located at the European Centre for Nuclear Research (CERN) in Switzerland. It is designed to measure decay properties of highly energetic particles produced in the protons collisions at the Large Hadron Collider (LHC). The LHC has a beam collision frequency of 40 MHz, and thus requires a trigger system to efficiently select events, thereby reducing the storage rate to a manageable level of about 400 Hz. Event triggering is therefore one of the extraordinary challenges faced by the ATLAS detector. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 75kHz and decision latency of less than 2.5 s. It is primarily composed of the Calorimeter Trigger, Muon Trigger, the Central Trigger Processor (CTP). Due to the increase in the LHC instantaneous luminosity up 3 x 10^34/cm2 s from 2015 onwards, a new element will be included in the Level-1 Trigger scheme: the Topological Processor (L1Topo). The L1Topo receives data in a specialized format from the ...

The ATLAS Liquid Argon Calorimeters: integration, installation and commissioning

International Nuclear Information System (INIS)

Tikhonov, Yu.

2008-01-01

The ATLAS liquid argon calorimeter system consists of an electromagnetic barrel calorimeter and two end-caps with electromagnetic, hadronic and forward calorimeters positioned in three cryostats. Since May 2006 the LAr barrel calorimeter records regular calibration runs and takes cosmic muon data together with tile hadronic calorimeter in the ATLAS cavern. The cosmic runs with end-cap calorimeters started in April 2007. First results of these combined runs are presented

Assembly of 5.5-Meter Diameter Developmental Barrel Segments for the Ares I Upper Stage

Science.gov (United States)

Carter, Robert W.

2011-01-01

Full scale assembly welding of Ares I Upper Stage 5.5-Meter diameter cryogenic tank barrel segments has been performed at the Marshall Space Flight Center (MSFC). One full-scale developmental article produced under the Ares 1 Upper Stage project is the Manufacturing Demonstration Article (MDA) Barrel. This presentation will focus on the welded assembly of this barrel section, and associated lessons learned. Among the MDA articles planned on the Ares 1 Program, the Barrel was the first to be completed, primarily because the process of manufacture from piece parts (barrel panels) utilized the most mature friction stir process planned for use on the Ares US program: Conventional fixed pin Friction Stir Welding (FSW). This process is in use on other space launch systems, including the Shuttle s External Tank, the Delta IV common booster core, the Delta II, and the Atlas V rockets. The goals for the MDA Barrel development were several fold: 1) to prove out Marshall Space Flight Center s new Vertical Weld Tool for use in manufacture of cylindrical barrel sections, 2) to serve as a first run for weld qualification to a new weld specification, and 3) to provide a full size cylindrical section for downstream use in precision cleaning and Spray-on Foam Insulation development. The progression leading into the welding of the full size barrel included sub scale panel welding, subscale cylinder welding, a full length confidence weld, and finally, the 3 seamed MDA barrel processing. Lessons learned on this MDA program have been carried forward into the production tooling for the Ares 1 US Program, and in the use of the MSFC VWT in processing other large scale hardware, including two 8.4 meter diameter Shuttle External Tank barrel sections that are currently being used in structural analysis to validate shell buckling models.

Two new wheels for ATLAS

CERN Multimedia

2002-01-01

Juergen Zimmer (Max Planck Institute), Roy Langstaff (TRIUMF/Victoria) and Sergej Kakurin (JINR), in front of one of the completed wheels of the ATLAS Hadronic End Cap Calorimeter. A decade of careful preparation and construction by groups in three continents is nearing completion with the assembly of two of the four 4 m diameter wheels required for the ATLAS Hadronic End Cap Calorimeter. The first two wheels have successfully passed all their mechanical and electrical tests, and have been rotated on schedule into the vertical position required in the experiment. 'This is an important milestone in the completion of the ATLAS End Cap Calorimetry' explains Chris Oram, who heads the Hadronic End Cap Calorimeter group. Like most experiments at particle colliders, ATLAS consists of several layers of detectors in the form of a 'barrel' and two 'end caps'. The Hadronic Calorimeter layer, which measures the energies of particles such as protons and pions, uses two techniques. The barrel part (Tile Calorimeter) cons...

Ultra-light and stable composite structure to support and cool the ATLAS pixel detector barrel electronics modules

International Nuclear Information System (INIS)

Olcese, M.; Caso, C.; Castiglioni, G.; Cereseto, R.; Cuneo, S.; Dameri, M.; Gemme, C.; Glitza, K.-W.; Lenzen, G.; Mora, F.; Netchaeva, P.; Ockenfels, W.; Piano, E.; Pizzorno, C.; Puppo, R.; Rebora, A.; Rossi, L.; Thadome, J.; Vernocchi, F.; Vigeolas, E.; Vinci, A.

2004-01-01

The design of an ultra light structure, the so-called 'stave', to support and cool the sensitive elements of the Barrel Pixel detector, the innermost part of the ATLAS detector to be installed on the new Large Hadron Collider at CERN (Geneva), is presented. Very high-dimensional stability, minimization of the material and ability of operating 10 years in a high radiation environment are the key design requirements. The proposed solution consists of a combination of different carbon-based materials (impregnated carbon-carbon, ultra high modulus carbon fibre composites) coupled to a thin aluminum tube to form a very light support with an integrated cooling channel. Our design has proven to successfully fulfil the requirements. The extensive prototyping and testing program to fully qualify the design and release the production are discussed

A level-1 track trigger for CMS with double stack detectors and long barrel approach

International Nuclear Information System (INIS)

Salvati, E

2012-01-01

The upgrade of the LHC machine is planned to deliver luminosities 5 to 10 times larger than the design one of 1 × 10 34 cm −2 s −1 . A novel tracking system for the CMS experiment must be designed and built. One main aspect of the current activities consists in understanding the capabilities that different designs such a tracker would have to provide for the Level 1 hardware trigger to complement the muon and calorimeter information. Data rate reduction at hardware level consists in both reducing multiple hits from a single track and rejection of low p t tracks. Pattern-based hit correlation of properly built clusters of hits would provide quality Level 1 primitives to the hardware trigger. These can be combined together in a projective geometry to perform a rough tracking to be implemented online, returning rough p t , direction, and vertex information for a candidate track. The benchmark results from simulations within the official CMS framework are presented for one particular layout based on barrel trigger layers, emphasizing the flexibility of this tool for the design and test of different tracking strategies at level 1 to be compared with the developments in trigger architectures implementation.

The ATLAS Level-1 Calorimeter Trigger Architecture

CERN Document Server

Garvey, J; Mahout, G; Moye, T H; Staley, R J; Watkins, P M; Watson, A T; Achenbach, R; Hanke, P; Kluge, E E; Meier, K; Meshkov, P; Nix, O; Penno, K; Schmitt, K; Ay, Cc; Bauss, B; Dahlhoff, A; Jakobs, K; Mahboubi, K; Schäfer, U; Trefzger, T M; Eisenhandler, E F; Landon, M; Moyse, E; Thomas, J; Apostoglou, P; Barnett, B M; Brawn, I P; Davis, A O; Edwards, J; Gee, C N P; Gillman, A R; Perera, V J O; Qian, W; Bohm, C; Hellman, S; Hidvégi, A; Silverstein, S; RT 2003 13th IEEE-NPSS Real Time Conference

2004-01-01

The architecture of the ATLAS Level-1 Calorimeter Trigger system (L1Calo) is presented. Common approaches have been adopted for data distribution, result merging, readout, and slow control across the three different subsystems. A significant amount of common hardware is utilized, yielding substantial savings in cost, spares, and development effort. A custom, high-density backplane has been developed with data paths suitable for both the em/tt cluster processor (CP) and jet/energy-summation processor (JEP) subsystems. Common modules also provide interfaces to VME, CANbus and the LHC Timing, Trigger and Control system (TTC). A common data merger module (CMM) uses FPGAs with multiple configurations for summing electron/photon and tau/hadron cluster multiplicities, jet multiplicities, or total and missing transverse energy. The CMM performs both crate- and system-level merging. A common, FPGA-based readout driver (ROD) is used by all of the subsystems to send input, intermediate and output data to the data acquis...

ATLAS level-1 calorimeter trigger hardware: initial timing and energy calibration

CERN Document Server

Childers, JT; The ATLAS collaboration

2010-01-01

The ATLAS Level-1 Calorimeter Trigger identifies high-pT objects in the Liquid Argon and Tile Calorimeters with a fixed latency of up to 2.4 microseconds using a hardware-based, pipelined system built with custom electronics. The Preprocessor Module conditions and digitizes about 7200 pre-summed analogue signals from the calorimeters at the LHC bunch-crossing frequency of 40 MHz, and performs bunch-crossing identification (BCID) and deposited energy measurement for each input signal. This information is passed to further processors for object classification and total energy calculation, and the results are used to make the Level-1 trigger decision for the ATLAS detector. The BCID and energy measurement in the trigger depend on precise timing adjustments to achieve correct sampling of the input signal peak. Test pulses from the calorimeters were analysed to derive the initial timing and energy calibration, and first data from the LHC restart in autumn 2009 and early 2010 were used for validation and further op...

Both ATLAS members and the team engaged in transport and reception, of the lower part of the central barrel of the tile hadronic calorimeter, will not forget installation of the first active piece of the detector!

CERN Multimedia

2004-01-01

Both ATLAS members and the team engaged in transport and reception, of the lower part of the central barrel of the tile hadronic calorimeter, will not forget installation of the first active piece of the detector!

First Combined SCT/TRT Cosmics Seen in SR1

CERN Multimedia

M. Jose Costa; H. Pernegger

A major milestone for the Inner Detector project has been accomplished in early May as cosmic rays going through both the barrel Semiconductor Tracker (SCT) and Transition Radiation Tracker (TRT) have been successfully recorded in the SR1 building on the ATLAS experimental site at CERN. A cosmic-ray track in the combined SCT-TRT barrel As reported also in this issue of the eNews, in February of this year the SCT barrel was inserted into the TRT in the SR1 building. One eighth of the TRT barrel and a quarter of the SCT barrel were then cabled to power supplies and to the data acquisition system in order to verify the good operation of the detector before installation in the ATLAS cavern. After first checks of noise levels in the final detectors, a critical goal was to study its response to cosmic rays using a set of scintillators to give the external trigger, thus undertaking the enormous challenge of integrating the full chain of the detectors, the DAQ, and the reconstruction and monitoring software. A ...

The new Level-1 Topological Trigger for the ATLAS experiment at the Large Hadron Collider

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00047907; The ATLAS collaboration

2017-01-01

At the CERN Large Hadron Collider, the world’s most powerful particle accelerator, the ATLAS experiment records high-energy proton collision to investigate the properties of fundamental particles. These collisions take place at a 40 MHz, and the ATLAS trigger system selects the interesting ones, reducing the rate to 1 kHz, allowing for their storage and subsequent offline analysis. The ATLAS trigger system is organized in two levels, with increasing degree of details and of accuracy. The first level trigger reduces the event rate to 100 kHz with a decision latency of less than 2.5 micro seconds. It is composed of the calorimeter trigger, muon trigger and central trigger processor. A new component of the first-level trigger was introduced in 2015: the Topological Processor (L1Topo). It allows to use detailed real-time information from the Level-1 calorimeter and muon systems, to compute advanced kinematic quantities using state of the art FPGA processors, and to select interesting events based on several com...

The Data Acquisition and Calibration System for the ATLAS Semiconductor Tracker

CERN Document Server

Abdesselam, A; Barr, A J; Bell, P; Bernabeu, J; Butterworth, J M; Carter, J R; Carter, A A; Charles, E; Clark, A; Colijn, A P; Costa, M J; Dalmau, J M; Demirkoz, B; Dervan, P J; Donega, M; D'Onifrio, M; Escobar, C; Fasching, D; Ferguson, D P S; Ferrari, P; Ferrère, D; Fuster, J; Gallop, B; García, C; González, S; González-Sevilla, S; Goodrick, M J; Gorisek, A; Greenall, A; Grillo, A A; Hessey, N P; Hill, J C; Jackson, J N; Jared, R C; Johannson, P D C; de Jong, P; Joseph, J; Lacasta, C; Lane, J B; Lester, C G; Limper, M; Lindsay, S W; McKay, R L; Magrath, C A; Mangin-Brinet, M; Martí i García, S; Mellado, B; Meyer, W T; Mikulec, B; Minano, M; Mitsou, V A; Moorhead, G; Morrissey, M; Paganis, E; Palmer, M J; Parker, M A; Pernegger, H; Phillips, A; Phillips, P W; Postranecky, M; Robichaud-Véronneau, A; Robinson, D; Roe, S; Sandaker, H; Sciacca, F; Sfyrla, A; Stanecka, E; Stapnes, S; Stradling, A; Tyndel, M; Tricoli, A; Vickey, T; Vossebeld, J H; Warren, M R M; Weidberg, A R; Wells, P S; Wu, S L

2008-01-01

The SemiConductor Tracker (SCT) data acquisition (DAQ) system will calibrate, configure, and control the approximately six million front-end channels of the ATLAS silicon strip detector. It will provide a synchronized bunch-crossing clock to the front-end modules, communicate first-level triggers to the front-end chips, and transfer information about hit strips to the ATLAS high-level trigger system. The system has been used extensively for calibration and quality assurance during SCT barrel and endcap assembly and for performance confirmation tests after transport of the barrels and endcaps to CERN. Operating in data-taking mode, the DAQ has recorded nearly twenty million synchronously-triggered events during commissioning tests including almost a million cosmic ray triggered events. In this paper we describe the components of the data acquisition system, discuss its operation in calibration and data-taking modes and present some detector performance results from these tests.

The data acquisition and calibration system for the ATLAS Semiconductor Tracker

International Nuclear Information System (INIS)

Abdesselam, A; Barr, A J; Demirkoez, B; Barber, T; Carter, J R; Bell, P; Bernabeu, J; Costa, M J; Escobar, C; Butterworth, J M; Carter, A A; Dalmau, J M; Charles, E; Fasching, D; Ferguson, D P S; Clark, A; Donega, M; D'Onifrio, M; Colijn, A-P; Dervan, P J

2008-01-01

The SemiConductor Tracker (SCT) data acquisition (DAQ) system will calibrate, configure, and control the approximately six million front-end channels of the ATLAS silicon strip detector. It will provide a synchronized bunch-crossing clock to the front-end modules, communicate first-level triggers to the front-end chips, and transfer information about hit strips to the ATLAS high-level trigger system. The system has been used extensively for calibration and quality assurance during SCT barrel and endcap assembly and for performance confirmation tests after transport of the barrels and endcaps to CERN. Operating in data-taking mode, the DAQ has recorded nearly twenty million synchronously-triggered events during commissioning tests including almost a million cosmic ray triggered events. In this paper we describe the components of the data acquisition system, discuss its operation in calibration and data-taking modes and present some detector performance results from these tests

The ATLAS Level-1 Topological Trigger performance in Run 2

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00120419; The ATLAS collaboration

2017-01-01

The Level-1 trigger is the first event rate reducing step in the ATLAS detector trigger system, with an output rate of up to 100 kHz and decision latency smaller than 2.5 μs. During the LHC shutdown after Run 1, the Level-1 trigger system was upgraded at hardware, firmware and software levels. In particular, a new electronics sub-system was introduced in the real-time data processing path: the Level-1 Topological trigger system. It consists of a single electronics shelf equipped with two Level-1 Topological processor blades. They receive real-time information from the Level-1 calorimeter and muon triggers, which is processed to measure angles between trigger objects, invariant masses or other kinematic variables. Complementary to other requirements, these measurements are taken into account in the final Level-1 trigger decision. The system was installed and commissioning started in 2015 and continued during 2016. As part of the commissioning, the decisions from individual algorithms were simulated and compar...

Resource Review Board Celebrates the Magnet and Liquid Argon Barrel Tests in Hall 180

CERN Multimedia

Jenni, P.

2004-01-01

Address by the Director-General, R. Aymar, in front of the barrel cryostat. On 25th October 2004 many RRB delegates and guests, ATLAS National Contact Physicists, and colleagues from far and from CERN working on the Liquid Argon calorimeter and the magnet system were gathering in Hall 180 to celebrate the major milestones reached during the past months in this hall: the successful cold tests of the first barrel toroid coil, of the solenoid, and of the barrel Liquid Argon calorimeter. About 250 people spent a relaxing evening after the speeches by the Director-General R. Aymar and by the spokesperson who gave the following address: 'It is a great pleasure for me to welcome you all here in Hall 180 in the name of the ATLAS Collaboration! With a few words I would like to recall why we are actually here today to share, what I hope, is a relaxed and joyful moment. To concentrate it all in one sentence I could say: To thank cordially all the main actors for the enormous work accomplished here over many years,...

A proposal to upgrade the ATLAS RPC system for the High Luminosity LHC

CERN Document Server

ATLAS Collaboration; The ATLAS collaboration

2015-01-01

The architecture of the present trigger system in the ATLAS Muon Barrel was designed according to a reference luminosity of 10^34 cm-2 s-1 with a safety factor of 5, with respect to the simulated background rates, now confirmed by LHC Run-1 data. HL-LHC will provide a luminosity 5 times higher and an order of magnitude higher background. As a result, the performance demand increases, while the detector being susceptible to ageing effects. Moreover, the present muon trigger acceptance in the barrel is just above 70%, due to the presence of the barrel toroid structures. This scenario induced the ATLAS muon Collaboration to propose an appropriate upgrade plan, involving both detector and trigger-readout electronics, to guarantee the performance required by the physics program for the 20 years scheduled. This consists in installing a layer of new generation RPCs in the inner barrel, to increase the redundancy, the selectivity, and provide almost full acceptance. The first 10% of the system, corresponding to the e...

Performance of the ATLAS Muon Trigger and Phase-1 Upgrade of Level-1 Endcap Muon Trigger

CERN Document Server

Mizukami, Atsushi; The ATLAS collaboration

2017-01-01

The ATLAS experiment utilises a trigger system to efficiently record interesting events. It consists of first-level and high-level triggers. The first-level trigger is implemented with custom-built hardware to reduce the event rate from 40 MHz to100 kHz. Then the software-based high-level triggers refine the trigger decisions reducing the output rate down to 1 kHz. Events with muons in the final state are an important signature for many physics topics at the LHC. An efficient trigger on muons and a detailed understanding of its performance are required. Trigger efficiencies are, for example, obtained from the muon decay of Z boson, with a Tag&Probe method, using proton-proton collision data collected in 2016 at a centre-of-mass energy of 13 TeV. The LHC is expected to increase its instantaneous luminosity to $3\\times10^{34} \\rm{cm^{-2}s^{-1}}$ after the phase-1 upgrade between 2018-2020. The upgrade of the ATLAS trigger system is mandatory to cope with this high-luminosity. In the phase-1 upgrade, new det...

Physics performances with the new ATLAS Level-1 Topological trigger in Run 2

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00414333; The ATLAS collaboration

2016-01-01

The ATLAS trigger system aims at reducing the 40 MHz proton-proton collision event rate to a manageable event storage rate of 1 kHz, preserving events valuable for physics analysis. The Level-1 trigger is the first rate-reducing step in the ATLAS trigger system, with an output rate of 100 kHz and decision latency of less than 2.5 micro seconds. It is composed of the calorimeter trigger, muon trigger and central trigger processor. During the last upgrade, a new electronics element was introduced to Level-1: The Topological Processor System. It will make it possible to use detailed realtime information from the Level-1 calorimeter and muon triggers, processed in individual state of the art FPGA processors to determine angles between jets and/or leptons and calculate kinematic variables based on lists of selected/sorted objects. More than one hundred VHDL algorithms are producing trigger outputs to be incorporated into the central trigger processor. This information will be essential to improve background reject...

Drift time measurement in the ATLAS liquid argon electromagnetic calorimeter using cosmic muons

DEFF Research Database (Denmark)

Aad..[], G.; Dam, Mogens; Hansen, Jørgen Beck

2010-01-01

The ionization signals in the liquid argon of the ATLAS electromagnetic calorimeter are studied in detail using cosmic muons. In particular, the drift time of the ionization electrons is measured and used to assess the intrinsic uniformity of the calorimeter gaps and estimate its impact...... on the constant term of the energy resolution. The drift times of electrons in the cells of the second layer of the calorimeter are uniform at the level of 1.3% in the barrel and 2.8% in the endcaps. This leads to an estimated contribution to the constant term of (0.29^{+0.05}_{-0.04})% in the barrel and (0...

ATLAS: First rehearsal for the tile calorimeter

CERN Multimedia

2003-01-01

The dry run assembly of the first barrel of the ATLAS tile hadron calorimeter has been successfully completed. It is now being dismantled again so that it can be lowered into the ATLAS cavern where it will be reassembled in October 2004.

ATLAS level-1 calorimeter trigger hardware: initial timing and energy calibration

International Nuclear Information System (INIS)

Childers, J T

2011-01-01

The ATLAS Level-1 Calorimeter Trigger identifies high-pT objects in the Liquid Argon and Tile Calorimeters with a fixed latency of up to 2.5μs using a hardware-based, pipelined system built with custom electronics. The Preprocessor Module conditions and digitizes about 7200 pre-summed analogue signals from the calorimeters at the LHC bunch-crossing frequency of 40 MHz, and performs bunch-crossing identification (BCID) and deposited energy measurement for each input signal. This information is passed to further processors for object classification and total energy calculation, and the results are used to make the Level-1 trigger decision for the ATLAS detector. The BCID and energy measurement in the trigger depend on precise timing adjustments to achieve correct sampling of the input signal peak. Test pulses from the calorimeters were analysed to derive the initial timing and energy calibration, and first data from the LHC restart in autumn 2009 and early 2010 were used for validation and further optimization. The results from these calibration measurements are presented.

3D Printing the ATLAS' barrel toroid

CERN Document Server

Goncalves, Tiago Barreiro

2016-01-01

The present report summarizes my work as part of the Summer Student Programme 2016 in the CERN IR-ECO-TSP department (International Relations – Education, Communication & Outreach – Teacher and Student Programmes). Particularly, I worked closely with the S’Cool LAB team on a science education project. This project included the 3D designing, 3D printing, and assembling of a model of the ATLAS’ barrel toroid. A detailed description of the project' development is presented and a short manual on how to use 3D printing software and hardware is attached.

Pre-Production Validation of the ATLAS Level-1 Calorimeter Trigger System

CERN Document Server

Achenbach, R; Barnett, B M; Bauss, B; Belkin, A; Bohm, C; Brawn, I P; Davis, A O; Edwards, J; Eisenhandler, E F; Föhlisch, F; Gee, C N P; Geweniger, C; Gillman, A R; Hanke, P; Hellman, S; Hidvégi, A; Hillier, S J; Kluge, E E; Landon, M; Mahboubi, K; Mahout, G; Meier, K; Mirea, A; Moye, T H; Perera, V J O; Qian, W; Rieke, S; Rühr, F; Sankey, D P C; Schäfer, U; Schmitt, K; Schultz-Coulon, H C; Silverstein, S; Staley, R J; Tapprogge, S; Thomas, J P; Trefzger, T; Typaldos, D; Watkins, P M; Watson, A; Weber, G A; Weber, P; 14th IEEE - NPSS Real Time Conference 2005 Nuclear Plasma Sciences Society

2005-01-01

The Level-1 Calorimeter Trigger is a major part of the first stage of event selection for the ATLAS experiment at the LHC. It is a digital, pipelined system with several stages of processing, largely based on FPGAs, which perform programmable algorithms in parallel with a fixed latency to process about 300 Gbyte/s of input data. The real-time output consists of counts of different types of trigger objects and energy sums. Prototypes of all module types have been undergoing intensive testing before final production during 2005. Verification of their correct operation has been performed standalone and in the ATLAS test-beam at CERN. Results from these investigations will be presented, along with a description of the methodology used to perform the tests.

The performance of the ATLAS Level-1 Calorimeter Trigger with LHC collision data

CERN Document Server

Bracinik, J

2011-01-01

The ATLAS first-level calorimeter trigger is a hardware-based system designed to identify high-E$_T$ jets, electron/photon and $ au$ candidates and to measure total and missing E$_T$ in the ATLAS calorimeters. After more than two years of commissioning in situ with calibration data and cosmic rays, the system has now been used extensively to select the most interesting proton-proton collision events. Fine tuning of timing and energy calibration has been carried out in 2010 to improve the trigger response to physics objects. In these proceedings, an analysis of the performance of the level-1 calorimeter trigger is presented, along with the techniques used to achieve these results.

Results from the Commissioning of the ATLAS Pixel Detector

CERN Document Server

Strandberg, S

2009-01-01

The ATLAS pixel detector is a high resolution, silicon based, tracking detector with its innermost layer located only 5 cm away from the ATLAS interaction point. It is designed to provide good hit resolution and low noise, both important qualities for pattern recognition and for finding secondary vertices originating from decays of long-lived particles. The pixel detector has 80 million readout channels and is built up of three barrel layers and six disks, three on each side of the barrel. The detector was installed in the center of ATLAS in June 2007 and is currently being calibrated and commissioned. Details from the installation, commissioning and calibration are presented together with the current status.

The ATLAS Liquid Argon Calorimeter: Construction, Integration, Commissioning

International Nuclear Information System (INIS)

Aleksa, Martin

2006-01-01

The ATLAS liquid argon (LAr) calorimeter system consists of an electromagnetic barrel calorimeter and two end caps with electromagnetic, hadronic and forward calorimeters. The liquid argon sampling technique, with an accordion geometry was chosen for the barrel electromagnetic calorimeter (EMB) and adapted to the end cap (EMEC). The hadronic end cap calorimeter (HEC) uses a copper-liquid argon sampling technique with flat plate geometry and is subdivided in depth in two wheels per end-cap. Finally, the forward calorimeter (FCAL) is composed of three modules employing cylindrical electrodes with thin liquid argon gaps.The construction of the full calorimeter system is complete since mid-2004. Production modules constructed in the home institutes were integrated into wheels at CERN in 2003-2004, and inserted into the three cryostats. They passed their first complete cold test before the lowering into the ATLAS cavern. Results of quality checks (e.g. electrical, mechanical, ...) performed on all the 190304 read-out channels after cool down will be reported. End 2004 the ATLAS barrel electromagnetic (EM) calorimeter was installed in the ATLAS cavern and since summer 2005 the front-end electronics are being connected and tested. Results of this first commissioning phase will be shown to demonstrate the high standards of quality control for our detectors

First modules of ATLAS's great accordion

CERN Multimedia

2001-01-01

The first CERN-built module of the barrel section of ATLAS's electromagnetic calorimeter has just been completed. This is the second in a series of 32 modules that will make up the final detector. These accordion-shaped structures will give precise measurements of the energy of particles produced in the LHC. The first CERN-built module of the barrel section of ATLAS's electromagnetic calorimeter nearing completion. Behind the module, from left to right: Ralf Huber, Andreas Bies and Jorgen Beck Hansen. In front of the module, from left to right: Philippe Lançon and Edward Wood. The builders of the ATLAS electromagnetic calorimeter are masters in the art of folding! To find out why, just take a look inside Hall 184, where the first CERN-built module of ATLAS's electromagnetic calorimeter has just been completed. It is the second in a long series, the first having been completed at the Saclay Laboratory of France's Commissariat à l'Energie Atomique just a few weeks ago. Thirty more remain...

Calibration of the ATLAS Tile hadronic calorimeter using muons

CERN Document Server

van Woerden, M C; The ATLAS collaboration

2012-01-01

The ATLAS Tile Calorimeter (TileCal) is the barrel hadronic calorimeter of the ATLAS experiment at the CERN Large Hadron Collider (LHC). It is a sampling calorimeter using plastic scintillator as the active material and iron as the absorber. TileCal , together with the electromagnetic calorimeter, provides precise measurements of hadrons, jets, taus and the missing transverse energy. Cosmic rays muons and muon events produced by scraping 450 GeV protons in one collimator of the LHC machine have been used to test the calibration of the calorimeter. The analysis of the cosmic rays data shows: a) the response of the third longitudinal layer of the Barrel differs from those of the first and second Barrel layers by about 3-4%, respectively and b) the differences between the energy scales of each layer obtained in this analysis and the value set at beam tests using electrons are found to range between -3% and +1%. In the case of the scraping beam data, the responses of all the layer pairs were found to be consisten...

Barrels XXIX: Barrels go Hollywood.

Science.gov (United States)

Evans, Mathew H; Brumberg, Joshua C

2017-03-01

Barrels XXIX brought together researchers focusing on the rodent barrel cortex and associated systems. The meeting revolved around three themes: thalamocortical interactions in motor control, touch in rodent, monkey, and humans, and the nature of the multisensory computations the brain makes. Over two days these topics were covered as well as many more presentations that focused on the physiology, behavior, and development of the rodent whisker-to-barrel cortex system.

The ATLAS high level trigger region of interest builder

International Nuclear Information System (INIS)

Blair, R.; Dawson, J.; Drake, G.; Haberichter, W.; Schlereth, J.; Zhang, J.; Ermoline, Y.; Pope, B.; Aboline, M.; High Energy Physics; Michigan State Univ.

2008-01-01

This article describes the design, testing and production of the ATLAS Region of Interest Builder (RoIB). This device acts as an interface between the Level 1 trigger and the high level trigger (HLT) farm for the ATLAS LHC detector. It distributes all of the Level 1 data for a subset of events to a small number of (16 or less) individual commodity processors. These processors in turn provide this information to the HLT. This allows the HLT to use the Level 1 information to narrow data requests to areas of the detector where Level 1 has identified interesting objects

gFEX, the ATLAS Calorimeter Level-1 Real Time Processor

CERN Document Server

AUTHOR|(SzGeCERN)759889; The ATLAS collaboration; Begel, Michael; Chen, Hucheng; Lanni, Francesco; Takai, Helio; Wu, Weihao

2016-01-01

The global feature extractor (gFEX) is a component of the Level-1 Calorimeter trigger Phase-I upgrade for the ATLAS experiment. It is intended to identify patterns of energy associated with the hadronic decays of high momentum Higgs, W, & Z bosons, top quarks, and exotic particles in real time at the LHC crossing rate. The single processor board will be packaged in an Advanced Telecommunications Computing Architecture (ATCA) module and implemented as a fast reconfigurable processor based on three Xilinx Vertex Ultra-scale FPGAs. The board will receive coarse-granularity information from all the ATLAS calorimeters on 276 optical fibers with the data transferred at the 40 MHz Large Hadron Collider (LHC) clock frequency. The gFEX will be controlled by a single system-on-chip processor, ZYNQ, that will be used to configure all the processor Field-Programmable Gate Array (FPGAs), monitor board health, and interface to external signals. Now, the pre-prototype board which includes one ZYNQ and one Vertex-7 FPGA ...

gFEX, the ATLAS Calorimeter Level 1 Real Time Processor

CERN Document Server

Tang, Shaochun; The ATLAS collaboration

2015-01-01

The global feature extractor (gFEX) is a component of the Level-1Calorimeter trigger Phase-I upgrade for the ATLAS experiment. It is intended to identify patterns of energy associated with the hadronic decays of high momentum Higgs, W, & Z bosons, top quarks, and exotic particles in real time at the LHC crossing rate. The single processor board will be packaged in an Advanced Telecommunications Computing Architecture (ATCA) module and implemented as a fast reconfigurable processor based on three Xilinx Ultra-scale FPGAs. The board will receive coarse-granularity information from all the ATLAS calorimeters on 264 optical fibers with the data transferred at the 40 MHz LHC clock frequency. The gFEX will be controlled by a single system-on-chip processor, ZYNQ, that will be used to configure all the processor FPGAs, monitor board health, and interface to external signals. Now, the pre-prototype board which includes one ZYNQ and one Vertex-7 FPGA has been designed for testing and verification. The performance ...

Calibration of the ATLAS hadronic barrel calorimeter TileCal using 2008, 2009 and 2010 cosmic rays data

CERN Document Server

The ATLAS collaboration

2011-01-01

Cosmic rays collected in 2008, 2009 and 2010 have been used in the ATLAS experiment to test the calibration of the hadronic barrel calorimeter TileCal. Stable results were obtained for the three periods. The analysis was based on the comparison between experimental and simulated data, and addresses three issues. First, the average non uniformity of the response of the cells within a layer was estimated to be about 2%. Second, the average response of different layers is found to be not intercalibrated, considering the sources of error. The largest difference between the responses of two layers is 4%. Finally, the differences between the energy scales of each layer obtained in this analysis and the value set at test beams using electrons was found to range between -2% and +2%. The sources of uncertainties in the response measurements are strongly correlated and include the uncertainty in the simulation of the muon response. The overall uncertainty in the energy scale is estimated to be 3%.

The development of Global Feature eXtractor (gFEX) - the ATLAS calorimeter Level 1 trigger for ATLAS at High Luminosity LHC

CERN Document Server

AUTHOR|(SzGeCERN)759889; The ATLAS collaboration; Begel, Michael; Chen, Hucheng; Chen, Kai; Lanni, Francesco; Takai, Helio; Wu, Weihao

2017-01-01

As part of the ATLAS Phase-I Upgrade, the gFEX is designed to help maintain the ATLAS Level-1 trigger acceptance rate with the increasing LHC luminosity. The gFEX identifies patterns of energy associated with the hadronic decays of high momentum Higgs, W, & Z bosons, top quarks, and exotic particles in real time at the 40MHz LHC bunch crossing rate. The prototype v1 and v2 were designed and fully tested in 2015 and 2016 respectively. A pre-production gFEX board has been manufactured, which is an ATCA module consisting of three UltraScale+ FPGAs and one ZYNQ UltraScale+, and 35 MiniPODs are implemented in an ATCA module. This board receives coarse-granularity (0.2x0.2) information from the entire ATLAS calorimeters on up to 300 optical fibers and 96 links to the L1Topo at the speed up to 12.8 Gb/s.

Multi-threaded algorithms for GPGPU in the ATLAS High Level Trigger

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00212700; The ATLAS collaboration

2017-01-01

General purpose Graphics Processor Units (GPGPU) are being evaluated for possible future inclusion in an upgraded ATLAS High Level Trigger farm. We have developed a demonstrator including GPGPU implementations of Inner Detector and Muon tracking and Calorimeter clustering within the ATLAS software framework. ATLAS is a general purpose particle physics experiment located on the LHC collider at CERN. The ATLAS Trigger system consists of two levels, with Level-1 implemented in hardware and the High Level Trigger implemented in software running on a farm of commodity CPU. The High Level Trigger reduces the trigger rate from the 100 kHz Level-1 acceptance rate to 1.5 kHz for recording, requiring an average per-event processing time of ∼ 250 ms for this task. The selection in the high level trigger is based on reconstructing tracks in the Inner Detector and Muon Spectrometer and clusters of energy deposited in the Calorimeter. Performing this reconstruction within the available farm resources presents a significa...

Wheels lining up for ATLAS

CERN Multimedia

2003-01-01

On 30 October, the mechanics test assembly of the central barrel of the ATLAS tile hadronic calorimeter was completed in building 185. It is the second wheel for the Tilecal completely assembled this year.

The ATLAS Level-1 Muon to Central Trigger Processor Interface

CERN Document Server

Berge, D; Farthouat, P; Haas, S; Klofver, P; Krasznahorkay, A; Messina, A; Pauly, T; Schuler, G; Spiwoks, R; Wengler, T; PH-EP

2007-01-01

The Muon to Central Trigger Processor Interface (MUCTPI) is part of the ATLAS Level-1 trigger system and connects the output of muon trigger system to the Central Trigger Processor (CTP). At every bunch crossing (BC), the MUCTPI receives information on muon candidates from each of the 208 muon trigger sectors and calculates the total multiplicity for each of six transverse momentum (pT) thresholds. This multiplicity value is then sent to the CTP, where it is used together with the input from the Calorimeter trigger to make the final Level-1 Accept (L1A) decision. In addition the MUCTPI provides summary information to the Level-2 trigger and to the data acquisition (DAQ) system for events selected at Level-1. This information is used to define the regions of interest (RoIs) that drive the Level-2 muontrigger processing. The MUCTPI system consists of a 9U VME chassis with a dedicated active backplane and 18 custom designed modules. The design of the modules is based on state-of-the-art FPGA devices and special ...

The ATLAS Level-1 Topological Trigger Design and Operation in Run-2

CERN Document Server

Igonkina, Olga; The ATLAS collaboration

2018-01-01

The ATLAS Level-1 Trigger system performs initial event selection using data from calorimeters and the muon spectrometer to reduce the LHC collision event rate down to about 100 kHz. Trigger decisions from the different sub-systems are combined in the Central Trigger Processor for the final Level-1 decision. A new FPGAs-based AdvancedTCA sub-system was introduced to calculate in real time complex kinematic observables: the Topological Processor System. It was installed during the shutdown and commissioning started in 2015 and continued during 2016. The design and operation of the Level-1 Topological Trigger in Run-2 will be illustrated.

Feasibility studies of a Level-1 Tracking Trigger for ATLAS

CERN Document Server

Warren, M; Brenner, R; Konstantinidis, N; Sutton, M

2009-01-01

The existing ATLAS Level-1 trigger system is seriously challenged at the SLHC's higher luminosity. A hardware tracking trigger might be needed, but requires a detailed understanding of the detector. Simulation of high pile-up events, with various data-reduction techniques applied will be described. Two scenarios are envisaged: (a) regional readout - calorimeter and muon triggers are used to identify portions of the tracker; and (b) track-stub finding using special trigger layers. A proposed hardware system, including data reduction on the front-end ASICs, readout within a super-module and integrating regional triggering into all levels of the readout system, will be discussed.

Liquid Argon Barrel Cryostat Arrived

CERN Multimedia

Pailler, P

Last week the first of three cryostats for the ATLAS liquid argon calorimeter arrived at CERN. It had travelled for 46 days over several thousand kilometers from Japan to CERN. During three years it has been fabricated by Kawasaki Heavy Industries Ltd. at Harima, close to Kobe, under contract from Brookhaven National Laboratory (BNL) of the U.S.. This cryostat consists of two concentric cylinders made of aluminium: the outer vacuum vessel with a diameter of 5.5 m and a length of 7 m, and the inner cold vessel which will contain the electromagnetic barrel calorimeter immersed in liquid argon. The total weight will be 270 tons including the detectors and the liquid argon. The cryostat is now located in building 180 where it will be equipped with 64 feed-throughs which serve for the passage of 122,880 electrical lines which will carry the signals of the calorimeter. After integration of the calorimeter, the solenoidal magnet of ATLAS will be integrated in the vacuum vessel. A final cold test of the cryostat inc...

Digital signal integrity and stability in the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Achenbach, R; Aharrouche, M; Andrei, V; Åsman, B; Barnett, B M; Bauss, B; Bendel, M; Bohm, C; Booth, J R A; Bracinik, J; Brawn, I P; Charlton, D G; Childers, J T; Collins, N J; Curtis, C J; Davis, A O; Eckweiler, S; Eisenhandler, E F; Faulkner, P J W; Fleckner, J; Föhlisch, F; Gee, C N P; Gillman, A R; Goringer, C; Groll, M; Hadley, D R; Hanke, P; Hellman, S; Hidvegi, A; Hillier, S J; Johansen, M; Kluge, E E; Kühl, T; Landon, M; Lendermann, V; Lilley, J N; Mahboubi, K; Mahout, G; Meier, K; Middleton, R P; Moa, T; Morris, J D; Müller, F; Neusiedl, A; Ohm, C; Oltmann, B; Perera, V J O; Prieur, D P F; Qian, W; Rieke, S; Rühr, F; Sankey, D P C; Schäfer, U; Schmitt, K; Schultz-Coulon, H C; Silverstein, S; Sjölin, J; Staley, R J; Stamen, R; Stockton, M C; Tan, C L A; Tapprogge, S; Thomas, J P; Thompson, P D; Watkins, P M; Watson, A; Weber, P; Wessels, M; Wildt, M

2008-01-01

The ATLAS Level-1 calorimeter trigger is a hardware-based system with the goal of identifying high-pT objects and to measure total and missing ET in the ATLAS calorimeters within an overall latency of 2.5 microseconds. This trigger system is composed of the Preprocessor which digitises about 7200 analogue input channels and two digital processors to identify high-pT signatures and to calculate the energy sums. The digital part consists of multi-stage, pipelined custom-built modules. The high demands on connectivity between the initial analogue stage and digital part and between the custom-built modules are presented. Furthermore the techniques to establish timing regimes and verify connectivity and stable operation of these digital links will be described.

Spanish Minister of Science and Technology visits ATLAS

CERN Multimedia

Patrice Loïez

2002-01-01

H.E. Mr Josep Piqué i Camps, Minister for Science and Technology, Spain, pictured in front of a barrel toroid cryostat vessel in the ATLAS assembly hall. The air-core ATLAS barrel toroid magnet system will consist of eight large superconducting coils, each in its own vacuum vessel, built by Spanish company Felguera Construcciones Mecanicas SA under the responsibility of IFAE (Institute for High Energy Physics), Barcelona. Photo 01: The Minister in front of the cryostat vessel. Photo 02: The Minister (right) with H.E. Mr Joaquin Pérez-Villanueva y Tovar, Spanish Ambassador to the United Nations in Geneva. Photo 03: (left to right) Manuel Delfino, leader of the Information Technology division at CERN; Matteo Cavalli-Sforza of CERN; Juan Antonio Rubio, leader of the Education and Technology Transfer division at CERN; The Minister; and Peter Jenni, ATLAS spokesperson.

Spinal canal stenosis at the level of Atlas

Directory of Open Access Journals (Sweden)

Suchanda Bhattacharjee

2011-01-01

Full Text Available We report here a rare case of high cervical stenosis at the level of atlas who presented with progressively deteriorating quadriparesis and respiratory distress. A 10-year-old boy presented with above symptoms of one-year duration with a preceding history of trivial trauma prior to onset of such symptoms. Cervical spine MRI revealed a significant stenosis at the level of atlas from the posterior side with a syrinx extending above and below. High-resolution computed tomography of the above level yielded an ill-defined osseous bar compressing the canal at the level of C 1 posterior arch, which appeared bifid in the midline. The patient was immediately taken up for surgery in view of his respiratory complaints. The child showed an excellent recovery after excision of the posterior arch of atlas and removal of the compressing osseous structure.

The barrel muon spectrometer of the ATLAS detector has acquired its first cosmic event in a magnetic field produced by the barrel toroid magnet.

CERN Multimedia

2006-01-01

A 3-D event display of a cosmic muon event, showing the path of a muon travelling through three layers of the barrel muon spectrometer. Three of the eight coils of the barrel toroid magnet can be seen in the top half of the drawing.

First observation of electrons in the ATLAS detector

CERN Document Server

Kraus, J; The ATLAS collaboration

2010-01-01

The special topology of cosmic events traversing all subdetectors offers the unique opportunity to investigate the combined performance of ATLAS in identifying and reconstructing particles before first collisions. High-energy delta electrons in cosmic data are studied which are produced by cosmic muons through ionisation of the inner detector material. A method of separating knock-on electrons from the large background of muon bremsstrahlung is presented accounting for the special nature of cosmic events and utilizing the ATLAS tools to identify electrons with their characteristic properties. The resulting isolation of a sample of 32 delta electrons out of 3.5 million cosmic ray events with a high-level trigger track candidate in the inner detector barrel has for the first time enabled an observation and investigation of real electrons in ATLAS.

Upgrade of the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

AUTHOR|(CDS)2072874

2014-01-01

The Level-1 calorimeter trigger (L1Calo) operated successfully during the first data taking phase of the ATLAS experiment at the LHC. Facing the new challenges posed by the upcoming increases of the LHC beam energy and luminosity, and from the experience of the previous running, a series of upgrades is planned for L1Calo. The initial upgrade phase in 2013-14 includes substantial improvements to the analogue and digital signal processing to cope with baseline shifts due to signal pile-up. Additionally a newly introduced system will receive real-time data from both the upgraded L1Calo and L1Muon trigger to perform trigger algorithms based on entire event topologies. During the second upgrade phase in 2018-19 major parts of L1Calo will be rebuilt in order to exploit a tenfold increase in the available calorimeter data granularity compared to that of the current system. The contribution gives an overview of the existing system and the lessons learned during the first period of LHC data taking. Based on these, the...

Upgrade of the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Mueller, Felix; The ATLAS collaboration

2014-01-01

The Level-1 calorimeter trigger (L1Calo) operated successfully during the first data taking phase of the ATLAS experiment at the LHC. Based on the lessons learned , a series of upgrades is planned for L1Calo to face the new challenges posed by the upcoming increases of the LHC beam energy and luminosity. The initial upgrade phase in 2013-14 includes substantial improvements to the analogue and digital signal processing to cope with baseline shifts due to signal pile-up. Additionally a newly introduced system will receive real-time data from both the upgraded L1Calo and L1Muon trigger to perform trigger algorithms based on entire event topologies. During the second upgrade phase in 2018-19 major parts of L1Calo will be rebuilt in order to exploit a tenfold increase in the available calorimeter data granularity compared to that of the current system. In this contribution we present the lessons learned during the first period of LHC data taking. Based on these we discuss the expected performance improvements tog...

Application of Cu-polyimide flex circuit and Al-on-glass pitch adapter for the ATLAS SCT barrel hybrid

CERN Document Server

Unno, Y; Ikegami, Y; Iwata, Y; Kohriki, T; Kondo, T; Nakano, I; Ohsugi, T; Takashima, R; Tanaka, R; Terada, S; Ujiie, N

2005-01-01

We applied the surface build-up Cu-polyimide flex-circuit technology with laser vias to the ATLAS SCT barrel hybrid to be made in one piece from the connector to the electronics sections including cables. The hybrids, reinforced with carbon-carbon substrates, provide mechanical strength, thermal conductivity, low-radiation length, and stability in application-specific integrated circuit (ASIC) operation. By following the design rules, we experienced little trouble in breaking the traces. The pitch adapter between the sensor and the ASICs was made of aluminum traces on glass substrate. We identified that the generation of whiskers around the wire-bonding feet was correlated with the hardness of metallized aluminum. The appropriate hardness has been achieved by keeping the temperature of the glasses as low as room temperature during the metallization. The argon plasma cleaning procedure cleaned the contamination on the gold pads of the hybrids for successful wire bonding, although it was unsuccessful in the alu...

Installation of the Liquid Argon Calorimater Barrel in the ATLAS Experimental Cavern

CERN Multimedia

Vandoni, G.

On the 27th of October, the Liquid Argon Barrel cryostat was transported from Building 180 to point 1. The next day, the Barrel was lowered into the cavern, and was placed on jacks close to its final position inside the completed lower half of the Tile calorimeter. After a day of precise adjustment, it was resting within a few millimetres of its nominal final position, waiting for the upper half of the Tile calorimeter to be installed. Tight requests had been issued by the Liquid Argon collaboration for the whole transport. It was foreseen that the cryostat should not see any acceleration larger than 0.15g along its axis, 0.08g transversally and 0.3g in the vertical direction. In addition, no acceleration higher than 0.03g (or even 0.003g for permanent oscillation) would be allowed at 20Hz, to avoid the risk of damaging the absorbers at this spontaneous vibration frequency. The difficulty would arise when coping these demands with the tortuous route, its slopes and curbs, vibration transmission from the engi...

The ATLAS semiconductor tracker (SCT)

International Nuclear Information System (INIS)

Jackson, J.N.

2005-01-01

The ATLAS detector (CERN,LHCC,94-43 (1994)) is designed to study a wide range of physics at the CERN Large Hadron Collider (LHC) at luminosities up to 10 34 cm -2 s -1 with a bunch-crossing rate of 40 MHz. The Semiconductor Tracker (SCT) forms a key component of the Inner Detector (vol. 1, ATLAS TDR 4, CERN,LHCC 97-16 (1997); vol. 2, ATLAS TDR 5, CERN,LHCC 97-17 (1997)) which is situated inside a 2 T solenoid field. The ATLAS Semiconductor Tracker (SCT) utilises 4088 silicon modules with binary readout mounted on carbon fibre composite structures arranged in the forms of barrels in the central region and discs in the forward region. The construction of the SCT is now well advanced. The design of the SCT modules, services and support structures will be briefly outlined. A description of the various stages in the construction process will be presented with examples of the performance achieved and the main difficulties encountered. Finally, the current status of the construction is reviewed

The ATLAS Level-2 Trigger Pilot Project

CERN Document Server

Wickens, F J

2000-01-01

The Level-2 Trigger Pilot Project of ATLAS, one of the two general purpose LHC experiments, is part of the on-going programme to develop the ATLAS High Level Triggers (HLT). The Level-2 Trigger will receive events at up to 100 kHz, which has to be reduced to a rate suitable for full event-building of the order of 1 kHz. To reduce the data collection bandwidth and processing power required for the challenging Level-2 task it is planned to use Region of Interest guidance (from Level-1) and sequential processing. The Pilot Project included the construction and use of testbeds of up to 48 processing nodes, development of optimised components and computer simulations of a full system. It has shown how the required performance can be achieved, using largely commodity components and operating systems, and validated an architecture for the Level-2 system. This paper describes the principal achievements and conclusions of this project. (28 refs).

The ATLAS Level-2 Trigger Pilot Project

CERN Document Server

Blair, R; Haberichter, W N; Schlereth, J L; Bock, R; Bogaerts, A; Boosten, M; Dobinson, Robert W; Dobson, M; Ellis, Nick; Elsing, M; Giacomini, F; Knezo, E; Martin, B; Shears, T G; Tapprogge, Stefan; Werner, P; Hansen, J R; Wäänänen, A; Korcyl, K; Lokier, J; George, S; Green, B; Strong, J; Clarke, P; Cranfield, R; Crone, G J; Sherwood, P; Wheeler, S; Hughes-Jones, R E; Kolya, S; Mercer, D; Hinkelbein, C; Kornmesser, K; Kugel, A; Männer, R; Müller, M; Sessler, M; Simmler, H; Singpiel, H; Abolins, M; Ermoline, Y; González-Pineiro, B; Hauser, R; Pope, B; Sivoklokov, S Yu; Boterenbrood, H; Jansweijer, P; Kieft, G; Scholte, R; Slopsema, R; Vermeulen, J C; Baines, J T M; Belias, A; Botterill, David R; Middleton, R; Wickens, F J; Falciano, S; Bystrický, J; Calvet, D; Gachelin, O; Huet, M; Le Dû, P; Mandjavidze, I D; Levinson, L; González, S; Wiedenmann, W; Zobernig, H

2002-01-01

The Level-2 Trigger Pilot Project of ATLAS, one of the two general purpose LHC experiments, is part of the on-going program to develop the ATLAS high-level triggers (HLT). The Level-2 Trigger will receive events at up to 100 kHz, which has to be reduced to a rate suitable for full event-building of the order of 1 kHz. To reduce the data collection bandwidth and processing power required for the challenging Level-2 task it is planned to use Region of Interest guidance (from Level-1) and sequential processing. The Pilot Project included the construction and use of testbeds of up to 48 processing nodes, development of optimized components and computer simulations of a full system. It has shown how the required performance can be achieved, using largely commodity components and operating systems, and validated an architecture for the Level-2 system. This paper describes the principal achievements and conclusions of this project. (28 refs).

The ATLAS Pixel Detector

CERN Document Server

Huegging, Fabian

2006-06-26

The contruction of the ATLAS Pixel Detector which is the innermost layer of the ATLAS tracking system is prgressing well. Because the pixel detector will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability for all parts, combined with a low material budget. The final detector layout, new results from production modules and the status of assembly are presented.

First physics pulses in the Barrel Electromagnetic Calorimeter with cosmics

CERN Multimedia

Laurent Serin

2006-01-01

The electromagnetic barrel calorimeter has been installed in its final position in October 2005. Since then, the calorimeter is being equipped with front-end electronics. Starting in April 2006, electronics calibration runs are taken a few times per week to debug the electronics and to study the performance in the pit (stability, noise). Today, 10 out of the 32 Front End crates are being read out, amounting to about 35000 channels. cool down, few little typos --> After a 6-week cool down, the barrel cryostat was filled with Liquid Argon in May. The presence of a few shorts (~1MΩ) at the edges of the modules was indicating the possibility of conducting dust having entered into the calorimeter with the flowing liquid. In order to try to improve this situation, the calorimeter was emptied and filled again, but this time by condensating the argon instead of flowing it in liquid phase. The new High Voltage tests are not showing any significant improvement but the situation is statisfactory for ATLAS runn...

Integration and test of the ATLAS Semiconductor Tracker

CERN Document Server

Pernegger, H

2007-01-01

The ATLAS Semiconductor Tracker (SCT) will be a central part of the tracking system of the ATLAS experiment and is one of the major new silicon detector systems for LHC. The paper summarizes the system integration of the SCT from individual components to the completed tracker barrel and endcaps ready for installation in the pit. Particular attention will be given to the test results obtained during the different integration steps: from single barrels and disks to the final tests inside the ID before installation in the pit. The tests provided us with operational experience for a significant fraction of the full detector system and showed the very good performance of the final assembled detector.

Drift Time Measurement in the ATLAS Liquid Argon Electromagnetic Calorimeter using Cosmic Muons

CERN Document Server

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Roa Romero, D A; Robertson, S.H.; Robichaud-Veronneau, A.; Robinson, D.; Robinson, J.; Robinson, M.; Robson, A.; Rocha de Lima, J G; Roda, C.; Roda Dos Santos, D; Rodriguez, D.; Rodriguez Garcia, Y; Roe, S.; Røhne, O.; Rojo, V.; Rolli, S.; Romaniouk, A.; Romanov, V.M.; Romeo, G.; Romero Maltrana, D; Roos, L.; Ros, E.; Rosati, S.; Rosenbaum, G.A.; Rosenberg, E.I.; Rosselet, L.; Rossetti, V.; Rossi, L.P.; Rotaru, M.; Rothberg, J.; Rottländer, I.; Rousseau, D.; Royon, C.R.; Rozanov, A.; Rozen, Y.; Ruan, X.; Ruckert, B.; Ruckstuhl, N.; Rud, V.I.; Rudolph, G.; Rühr, F.; Ruggieri, F.; Ruiz-Martinez, A.; Rumyantsev, L.; Rusakovich, N.A.; Rutherfoord, J.P.; Ruwiedel, C.; Ruzicka, P.; Ryabov, Y.F.; Ryadovikov, V.; Ryan, P.; Rybkin, G.; Rzaeva, S.; Saavedra, A.F.; Sadrozinski, H.F.W.; Sadykov, R.; Sakamoto, H.; Salamanna, G.; Salamon, A.; Saleem, M.; Salihagic, D.; Salnikov, A.; Salt, J.; Salvachua Ferrando, B M; Salvatore, D.; Salvatore, F.; Salvucci, A.; Salzburger, A.; Sampsonidis, D.; Samset, B.H.; Sanchis Lozano, M A; Sandaker, H.; Sander, H.G.; Sanders, M.P.; Sandhoff, M.; Sandstroem, R.; Sandvoss, S.; Sankey, D.P.C.; Sanny, B.; Sansoni, A.; Santamarina Rios, C; Santi, L.; Santoni, C.; Santonico, R.; Santos, J.; Saraiva, J.G.; Sarangi, T.; Sarkisyan-Grinbaum, E.; Sarri, F.; Sasaki, O.; Sasaki, T.; Sasao, N.; Satsounkevitch, I.; Sauvage, G.; Savard, P.; Savine, A.Y.; Savinov, V.; Sawyer, L.; Saxon, D.H.; Says, L.P.; Sbarra, C.; Sbrizzi, A.; Scannicchio, D.A.; Schaarschmidt, J.; Schacht, P.; Schäfer, U.; Schaetzel, S.; Schaffer, A.C.; Schaile, D.; Schamberger, R.D.; Schamov, A.G.; Schegelsky, V.A.; Scheirich, D.; Schernau, M.; Scherzer, M.I.; Schiavi, C.; Schieck, J.; Schioppa, M.; Schlenker, S.; Schlereth, J.L.; Schmid, P.; Schmieden, K.; Schmitt, C.; Schmitz, M.; Schott, M.; Schouten, D.; Schovancova, J.; Schram, M.; Schreiner, A.; Schroeder, C.; Schroer, N.; Schroers, M.; Schuler, G.; Schultes, J.; Schultz-Coulon, H.C.; Schumacher, J.W.; Schumacher, M.; Schumm, B.A.; Schune, Ph; Schwanenberger, C.; Schwartzman, A.; Schwemling, Ph; Schwienhorst, R.; Schwierz, R.; Schwindling, J.; Scott, W.G.; Searcy, J.; Sedykh, E.; Segura, E.; Seidel, S.C.; Seiden, A.; Seifert, F.; Seixas, J.M.; Sekhniaidze, G.; Seliverstov, D.M.; Sellden, B.; Seman, M.; Semprini-Cesari, N.; Serfon, C.; Serin, L.; Seuster, R.; Severini, H.; Sevior, M.E.; Sfyrla, A.; Shabalina, E.; Shamim, M.; Shan, L.Y.; Shank, J.T.; Shao, Q.T.; Shapiro, M.; Shatalov, P.B.; Shaver, L.; Shaw, K.; Sherman, D.; Sherwood, P.; Shibata, A.; Shimojima, M.; Shin, T.; Shmeleva, A.; Shochet, M.J.; Shupe, M.A.; Sicho, P.; Sidoti, A.; Siebel, A.; Siegert, F.; Siegrist, J.; Sijacki, Dj; Silbert, O.; Silva, J.; Silver, Y.; Silverstein, D.; Silverstein, S.B.; Simak, V.; Simic, Lj; Simion, S.; Simmons, B.; Simonyan, M.; Sinervo, P.; Sinev, N.B.; Sipica, V.; Siragusa, G.; Sisakyan, A.N.; Sivoklokov, S.Yu.; Sjoelin, J.; Sjursen, T.B.; Skubic, P.; Skvorodnev, N.; Slater, M.; Slavicek, T.; Sliwa, K.; Sloper, J.; Sluka, T.; Smakhtin, V.; Smirnov, S.Yu.; Smirnov, Y.; Smirnova, L.N.; Smirnova, O.; Smith, B.C.; Smith, D.; Smith, K.M.; Smizanska, M.; Smolek, K.; Snesarev, A.A.; Snow, S.W.; Snow, J.; Snuverink, J.; Snyder, S.; Soares, M.; Sobie, R.; Sodomka, J.; Soffer, A.; Solans, C.A.; Solar, M.; Solc, J.; Solfaroli Camillocci, E; Solodkov, A.A.; Solovyanov, O.V.; Soluk, R.; Sondericker, J.; Sopko, V.; Sopko, B.; Sosebee, M.; Sosnovtsev, V.V.; Sospedra Suay, L; Soukharev, A.; Spagnolo, S.; Spanó, F.; Speckmayer, P.; Spencer, E.; Spighi, R.; Spigo, G.; Spila, F.; Spiwoks, R.; Spousta, M.; Spreitzer, T.; Spurlock, B.; St Denis, R D; Stahl, T.; Stahlman, J.; Stamen, R.; Stancu, S.N.; Stanecka, E.; Stanek, R.W.; Stanescu, C.; Stapnes, S.; Starchenko, E.A.; Stark, J.; Staroba, P.; Starovoitov, P.; Stastny, J.; Staude, A.; Stavina, P.; Stavropoulos, G.; Steele, G.; Steinbach, P.; Steinberg, P.; Stekl, I.; Stelzer, B.; Stelzer, H.J.; Stelzer-Chilton, O.; Stenzel, H.; Stevenson, K.; Stewart, G.; Stockton, M.C.; Stoerig, K.; Stoicea, G.; Stonjek, S.; Strachota, P.; Stradling, A.; Straessner, A.; Strandberg, J.; Strandberg, S.; Strandlie, A.; Strauss, M.; Strizenec, P.; Ströhmer, R.; Strom, D.M.; Strong, J.A.; Stroynowski, R.; Strube, J.; Stugu, B.; Stumer, I.; Soh, D.A.; Su, D.; Suchkov, S.I.; Sugaya, Y.; Sugimoto, T.; Suhr, C.; Suk, M.; Sulin, V.V.; Sultansoy, S.; Sumida, T.; Sun, X.; Sundermann, J.E.; Suruliz, K.; Sushkov, S.; Susinno, G.; Sutton, M.R.; Suzuki, T.; Suzuki, Y.; Sviridov, Yu M; Sykora, I.; Sykora, T.; Szymocha, T.; Sánchez, J.; Ta, D.; Tackmann, K.; Taffard, A.; Tafirout, R.; Taga, A.; Takahashi, Y.; Takai, H.; Takashima, R.; Takeda, H.; Takeshita, T.; Talby, M.; Talyshev, A.; Tamsett, M.C.; Tanaka, J.; Tanaka, R.; Tanaka, S.; Tanaka, S.; Tappern, G.P.; Tapprogge, S.; Tardif, D.; Tarem, S.; Tarrade, F.; Tartarelli, G.F.; Tas, P.; Tasevsky, M.; Tassi, E.; Tatarkhanov, M.; Taylor, C.; Taylor, F.E.; Taylor, G.N.; Taylor, R.P.; Taylor, W.; Teixeira-Dias, P.; Ten Kate, H; Teng, P.K.; Tennenbaum-Katan, Y.D.; Terada, S.; Terashi, K.; Terron, J.; Terwort, M.; Testa, M.; Teuscher, R.J.; Tevlin, C.M.; Thadome, J.; Thananuwong, R.; Thioye, M.; Thoma, S.; Thomas, J.P.; Thomas, T.L.; Thompson, E.N.; Thompson, P.D.; Thompson, P.D.; Thompson, R.J.; Thompson, A.S.; Thomson, E.; Thun, R.P.; Tic, T.; Tikhomirov, V.O.; Tikhonov, Y.A.; Timmermans, C.J.W.P.; Tipton, P.; Tique Aires Viegas, F J; Tisserant, S.; Tobias, J.; Toczek, B.; Todorov, T.; Todorova-Nova, S.; Toggerson, B.; Tojo, J.; Tokár, S.; Tokushuku, K.; Tollefson, K.; Tomasek, L.; Tomasek, M.; Tomasz, F.; Tomoto, M.; Tompkins, D.; Tompkins, L.; Toms, K.; Tong, G.; Tonoyan, A.; Topfel, C.; Topilin, N.D.; Torrence, E.; Torró Pastor, E; Toth, J.; Touchard, F.; Tovey, D.R.; Tovey, S.N.; Trefzger, T.; Tremblet, L.; Tricoli, A.; Trigger, I.M.; Trincaz-Duvoid, S.; Trinh, T.N.; Tripiana, M.F.; Triplett, N.; Trischuk, W.; Trivedi, A.; Trocmé, B.; Troncon, C.; Trzupek, A.; Tsarouchas, C.; Tseng, J.C.L.; Tsiafis, I.; Tsiakiris, M.; Tsiareshka, P.V.; Tsionou, D.; Tsipolitis, G.; Tsiskaridze, V.; Tskhadadze, E.G.; Tsukerman, I.I.; Tsulaia, V.; Tsung, J.W.; Tsuno, S.; Tsybychev, D.; Turala, M.; Turecek, D.; Turk Cakir, I; Turlay, E.; Tuts, P.M.; Twomey, M.S.; Tylmad, M.; Tyndel, M.; Tzanakos, G.; Uchida, K.; Ueda, I.; Ugland, M.; Uhlenbrock, M.; Uhrmacher, M.; Ukegawa, F.; Unal, G.; Underwood, D.G.; Undrus, A.; Unel, G.; Unno, Y.; Urbaniec, D.; Urkovsky, E.; Urquijo, P.; Urrejola, P.; Usai, G.; Uslenghi, M.; Vacavant, L.; Vacek, V.; Vachon, B.; Vahsen, S.; Valenta, J.; Valente, P.; Valentinetti, S.; Valkar, S.; Valladolid Gallego, E; Vallecorsa, S.; Valls Ferrer, J A; Van Berg, R; van der Graaf, H; van der Kraaij, E; van der Poel, E; Van Der Ster, D; van Eldik, N; van Gemmeren, P; van Kesteren, Z; van Vulpen, I; Vandelli, W.; Vandoni, G.; Vaniachine, A.; Vankov, P.; Vannucci, F.; Varela Rodriguez, F; Vari, R.; Varnes, E.W.; Varouchas, D.; Vartapetian, A.; Varvell, K.E.; Vasilyeva, L.; Vassilakopoulos, V.I.; Vazeille, F.; Vegni, G.; Veillet, J.J.; Vellidis, C.; Veloso, F.; Veness, R.; Veneziano, S.; Ventura, A.; Ventura, D.; Venturi, M.; Venturi, N.; Vercesi, V.; Verducci, M.; Verkerke, W.; Vermeulen, J.C.; Vetterli, M.C.; Vichou, I.; Vickey, T.; Viehhauser, G.H.A.; Villa, M.; Villani, E.G.; Villaplana Perez, M; Villate, J.; Vilucchi, E.; Vincter, M.G.; Vinek, E.; Vinogradov, V.B.; Viret, S.; Virzi, J.; Vitale, A.; Vitells, O.V.; Vivarelli, I.; Vives Vaques, F; Vlachos, S.; Vlasak, M.; Vlasov, N.; Vogel, A.; Vokac, P.; Volpi, M.; Volpini, G.; von der Schmitt, H; von Loeben, J; von Radziewski, H; von Toerne, E; Vorobel, V.; Vorobiev, A.P.; Vorwerk, V.; Vos, M.; Voss, R.; Voss, T.T.; Vossebeld, J.H.; Vranjes, N.; Vranjes Milosavljevic, M; Vrba, V.; Vreeswijk, M.; Vu Anh, T; Vudragovic, D.; Vuillermet, R.; Vukotic, I.; Wagner, P.; Wahlen, H.; Walbersloh, J.; Walder, J.; Walker, R.; Walkowiak, W.; Wall, R.; Wang, C.; Wang, H.; Wang, J.; Wang, J.C.; Wang, S.M.; Ward, C.P.; Warsinsky, M.; Wastie, R.; Watkins, P.M.; Watson, A.T.; Watson, M.F.; Watts, G.; Watts, S.; Waugh, A.T.; Waugh, B.M.; Webel, M.; Weber, J.; Weber, M.D.; Weber, M.; Weber, M.S.; Weber, P.; Weidberg, A.R.; Weingarten, J.; Weiser, C.; Wellenstein, H.; Wells, P.S.; Wen, M.; Wenaus, T.; Wendler, S.; Wengler, T.; Wenig, S.; Wermes, N.; Werner, M.; Werner, P.; Werth, M.; Werthenbach, U.; Wessels, M.; Whalen, K.; Wheeler-Ellis, S.J.; Whitaker, S.P.; White, A.; White, M.J.; White, S.; Whiteson, D.; Whittington, D.; Wicek, F.; Wicke, D.; Wickens, F.J.; Wiedenmann, W.; Wielers, M.; Wienemann, P.; Wiglesworth, C.; Wiik, L.A.M.; Wildauer, A.; Wildt, M.A.; Wilhelm, I.; Wilkens, H.G.; Williams, E.; Williams, H.H.; Willis, W.; Willocq, S.; Wilson, J.A.; Wilson, M.G.; Wilson, A.; Wingerter-Seez, I.; Winklmeier, F.; Wittgen, M.; Wolter, M.W.; Wolters, H.; Wosiek, B.K.; Wotschack, J.; Woudstra, M.J.; Wraight, K.; Wright, C.; Wright, D.; Wrona, B.; Wu, S.L.; Wu, X.; Wulf, E.; Xella, S.; Xie, S.; Xie, Y.; Xu, D.; Xu, N.; Yamada, M.; Yamamoto, A.; Yamamoto, S.; Yamamura, T.; Yamanaka, K.; Yamaoka, J.; Yamazaki, T.; Yamazaki, Y.; Yan, Z.; Yang, H.; Yang, U.K.; Yang, Y.; Yang, Z.; Yao, W.M.; Yao, Y.; Yasu, Y.; Ye, J.; Ye, S.; Yilmaz, M.; Yoosoofmiya, R.; Yorita, K.; Yoshida, R.; Young, C.; Youssef, S.P.; Yu, D.; Yu, J.; Yu, M.; Yu, X.; Yuan, J.; Yuan, L.; Yurkewicz, A.; Zaidan, R.; Zaitsev, A.M.; Zajacova, Z.; Zambrano, V.; Zanello, L.; Zarzhitsky, P.; Zaytsev, A.; Zeitnitz, C.; Zeller, M.; Zema, P.F.; Zemla, A.; Zendler, C.; Zenin, O.; Zenis, T.; Zenonos, Z.; Zenz, S.; Zerwas, D.; Zevi della Porta, G; Zhan, Z.; Zhang, H.; Zhang, J.; Zhang, Q.; Zhang, X.; Zhao, L.; Zhao, T.; Zhao, Z.; Zhemchugov, A.; Zheng, S.; Zhong, J.; Zhou, B.; Zhou, N.; Zhou, Y.; Zhu, C.G.; Zhu, H.; Zhu, Y.; Zhuang, X.; Zhuravlov, V.; Zimmermann, R.; Zimmermann, S.; Zimmermann, S.; Ziolkowski, M.; Zitoun, R.; Zivkovic, L.; Zmouchko, V.V.; Zobernig, G.; Zoccoli, A.; zur Nedden, M; Zutshi, V.

2010-01-01

The ionization signals in the liquid argon of the ATLAS electromagnetic calorimeter are studied in detail using cosmic muons. In particular, the drift time of the ionization electrons is measured and used to assess the intrinsic uniformity of the calorimeter gaps and estimate its impact on the constant term of the energy resolution. The drift times of electrons in the cells of the second layer of the calorimeter are uniform at the level of 1.3% in the barrel and 2.7% in the endcaps. This leads to an estimated contribution to the constant term of 0.29% in the barrel and 0.53% in the endcaps. The same data are used to measure the drift velocity of ionization electrons in liquid argon, which is found to be 4.61 +- 0.07 mm/microsecond at 88.5 K and 1 kV/mm.

ATLAS solenoid operates underground

CERN Multimedia

2006-01-01

A new phase for the ATLAS collaboration started with the first operation of a completed sub-system: the Central Solenoid. Teams monitoring the cooling and powering of the ATLAS solenoid in the control room. The solenoid was cooled down to 4.5 K from 17 to 23 May. The first current was established the same evening that the solenoid became cold and superconductive. 'This makes the ATLAS Central Solenoid the very first cold and superconducting magnet to be operated in the LHC underground areas!', said Takahiko Kondo, professor at KEK. Though the current was limited to 1 kA, the cool-down and powering of the solenoid was a major milestone for all of the control, cryogenic, power and vacuum systems-a milestone reached by the hard work and many long evenings invested by various teams from ATLAS, all of CERN's departments and several large and small companies. Since the Central Solenoid and the barrel liquid argon (LAr) calorimeter share the same cryostat vacuum vessel, this achievement was only possible in perfe...

ATLAS level-1 jet trigger rates and study of the ATLAS discovery potential of the neutral MSSM Higgs bosons in b-jet decay channels

CERN Document Server

Mahboubi, Kambiz

2001-01-01

The response of the ATLAS calorimeters to electrons, photons and hadrons, in terms of the longitudinal and lateral shower development, is parameterized using the GEANT package and a detailed detector description (DICE). The parameterizations are implemented in the ATLAS Level-1 (LVL1) Calorimeter Trigger fast simulation package which, based on an average detector geometry, simulates the complete chain of the LVL1 calorimeter trigger system. In addition, pile-up effects due to multiple primary interactions are implemented taking into account the shape and time history of the trigger signals. An interface to the fast physics simulation package (ATLFAST) is also developed in order to perform ATLAS physics analysis, including the LVL1 trigger effects, in a consistent way. The simulation tools, the details of the parameterization and the interface are described. The LVL1 jet trigger thresholds corresponding to the current trigger menus are determined within the framework of the fast simulation, and the LVL1 jet tr...

Towards a Level-1 tracking trigger for the ATLAS experiment

CERN Document Server

Cerri, A; The ATLAS collaboration

2014-01-01

The future plans for the LHC accelerator allow, through a schedule of phased upgrades, an increase in the average instantaneous luminosity by a factor 5 with respect to the original design luminosity. The ATLAS experiment at the LHC will be able to maximise the physics potential from this higher luminosity only if the detector, trigger and DAQ infrastructure are adapted to handle the sustained increase in particle production rates. In this paper the changes expected to be required to the ATLAS detectors and trigger system to fulfill the requirement for working in such high luminosity scenario are described. The increased number of interactions per bunch crossing will result in higher occupancy in the detectors and increased rates at each level of the trigger system. The trigger selection will improve the selectivity partly from increased granularity for the sub detectors and the consequent higher resolution. One of the largest challenges will be the provision of tracking information at the first trigger level...

Upgrade of the PreProcessor System for the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Khomich, A

2010-01-01

The ATLAS Level-1 Calorimeter Trigger is a hardware-based pipelined system designed to identify high-pT objects in the ATLAS calorimeters within a fixed latency of 2.5\\,us. It consists of three subsystems: the PreProcessor which conditions and digitizes analogue signals and two digital processors. The majority of the PreProcessor's tasks are performed on a dense Multi-Chip Module(MCM) consisting of FADCs, a time-adjustment and digital processing ASICs, and LVDS serialisers designed and implemented in ten years old technologies. An MCM substitute, based on today's components (dual channel FADCs and FPGA), is being developed to profit from state-of-the-art electronics and to enhance the flexibility of the digital processing. Development and first test results are presented.

TRT Barrel milestones passed

CERN Multimedia

Ogren, H

2004-01-01

The barrel TRT detector passed three significant milestones this spring. The Barrel Support Structure (BSS) was completed and moved to the SR-1 building on February 24th. On March 12th the first module passed the quality assurance testing in Building 154 and was transported to the assembly site in the SR-1 building for barrel assembly. Then on April 21st the final production module that had been scanned at Hampton University was shipped to CERN. TRT Barrel Module Production The production of the full complement of barrel modules (96 plus 9 total spares) is now complete. This has been a five-year effort by Duke University, Hampton University, and Indiana University. Actual construction of the modules in the United States was completed in the first part of 2004. The production crews at each of the sites in the United States have now completed their missions. They are shown in the following pictures. Duke University: Production crew with the final completed module. Indiana University: Module producti...

The Phase-1 Upgrade of the 
ATLAS Level-1 Endcap Muon Trigger

CERN Document Server

Akatsuka, Shunichi; The ATLAS collaboration

2018-01-01

Talk slides for RealTime 2018, 9th -15th June 2018 @ Williamsburg, Virginia, USA. Time slot 20 min. (probably 15 min. presentation + 5 min. discussion). This talk is on Phase-1 Upgrade of the Level-1 Endcap Muon trigger. The first part of this presentation describes the overview of the ATLAS trigger system, muon trigger in Run 2 and the Phase-1 Upgrade, and the strategy of phase-1 upgrade. Then in the following few pages, the physics algorithm of the Run 3 muon trigger and its performance is described. The main focus of this talk is on the implementation of the trigger logic to the FPGA. The key component of the trigger part implementation is described, using a schematic diagram and a simulation output screenshot.

The CMS Barrel Muon trigger upgrade

International Nuclear Information System (INIS)

Triossi, A.; Sphicas, P.; Bellato, M.; Montecassiano, F.; Ventura, S.; Ruiz, J.M. Cela; Bedoya, C. Fernandez; Tobar, A. Navarro; Fernandez, I. Redondo; Ferrero, D. Redondo; Sastre, J.; Ero, J.; Wulz, C.; Flouris, G.; Foudas, C.; Loukas, N.; Mallios, S.; Paradas, E.; Guiducci, L.; Masetti, G.

2017-01-01

The increase of luminosity expected by LHC during Phase1 will impose tighter constraints for rate reduction in order to maintain high efficiency in the CMS Level1 trigger system. The TwinMux system is the early layer of the muon barrel region that concentrates the information from different subdetectors: Drift Tubes, Resistive Plate Chambers and Outer Hadron Calorimeter. It arranges the slow optical trigger links from the detector chambers into faster links (10 Gbps) that are sent in multiple copies to the track finders. Results from collision runs, that confirm the satisfactory operation of the trigger system up to the output of the barrel track finder, will be shown.

ATLAS Tile Calorimeter central barrel assembly and installation.

CERN Multimedia

nikolai topilin

2009-01-01

These photos belong to the self-published book by Nikolai Topilin "ATLAS Hadron Calorimeter Assembly". The book is a collection of souvenirs from the years of assembly and installation of the Tile Hadron Calorimeter, which extended from November 2002 until May 2006.

Commissioning and validation of the ATLAS Level-1 topological trigger

CERN Document Server

AUTHOR|(SzGeCERN)788741; The ATLAS collaboration; Hong, Tae Min

2017-01-01

The ATLAS experiment has recently commissioned a new hardware component of its first-level trigger: the topological processor (L1Topo). This innovative system, using state-of-the-art FPGA processors, selects events by applying kinematic and topological requirements on candidate objects (energy clusters, jets, and muons) measured by calorimeters and muon sub-detectors. Since the first-level trigger is a synchronous pipelined system, such requirements are applied within a latency of 200ns. We will present the first results from data recorded using the L1Topo trigger; these demonstrate a significantly improved background event rejection, thus allowing for a rate reduction without efficiency loss. This improvement has been shown for several physics processes leading to low-$P_{T}$ leptons, including $H\\to{}\\tau{}\\tau{}$ and $J/\\Psi\\to{}\\mu{}\\mu{}$. In addition, we will discuss the use of an accurate L1Topo simulation as a powerful tool to validate and optimize the performance of this new trigger system. To reach ...

Tests of Local Hadron Calibration Approaches in ATLAS Combined Beam Tests

International Nuclear Information System (INIS)

Grahn, Karl-Johan; Kiryunin, Andrey; Pospelov, Guennadi

2011-01-01

Three ATLAS calorimeters in the region of the forward crack at |η| 3.2 in the nominal ATLAS setup and a typical section of the two barrel calorimeters at |η| = 0.45 of ATLAS have been exposed to combined beam tests with single electrons and pions. Detailed shower shape studies of electrons and pions with comparisons to various Geant4 based simulations utilizing different physics lists are presented for the endcap beam test. The local hadron calibration approach as used in the full Atlas setup has been applied to the endcap beam test data. An extension of it using layer correlations has been tested with the barrel test beam data. Both methods utilize modular correction steps based on shower shape variables to correct for invisible energy inside the reconstructed clusters in the calorimeters (compensation) and for lost energy deposits outside of the reconstructed clusters (dead material and out-of-cluster deposits). Results for both methods and comparisons to Monte Carlo simulations are presented.

The Phase-II ATLAS ITk Pixel Upgrade

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00349918; The ATLAS collaboration

2017-01-01

The entire tracking system of the ATLAS experiment will be replaced during the LHC Phase~2 shutdown (foreseen to take place around 2025) by an all-silicon detector called the ``ITk'' (Inner Tracker). The innermost portion of ITk will consist of a pixel detector with five layers in the barrel region and ring-shaped supports in the end-cap regions. It will be instrumented with new sensor and readout electronics technologies to improve the tracking performance and cope with the HL-LHC environment, which will be severe in terms of occupancy and radiation levels. The new pixel system could include up to 14 $\\mathrm{m^2}$ of silicon, depending on the final layout, which is expected to be decided in 2017. Several layout options are being investigated at the moment, including some with novel inclined support structures in the barrel end-cap overlap region and others with very long innermost barrel layers. Forward coverage could be as high as |eta| $<4$. Supporting structures will be based on low mass, highly stabl...

Towards a Level-1 tracking trigger for the ATLAS experiment at the High Luminosity LHC

CERN Document Server

Martin, T A D; The ATLAS collaboration

2014-01-01

At the high luminosity HL-LHC, upwards of 160 individual proton-proton interactions (pileup) are expected per bunch-crossing at luminosities of around $5\\times10^{34}$ cm$^{-2}$s$^{-1}$. A proposal by the ATLAS collaboration to split the ATLAS first level trigger in to two stages is briefly detailed. The use of fast track finding in the new first level trigger is explored as a method to provide the discrimination required to reduce the event rate to acceptable levels for the read out system while maintaining high efficiency on the selection of the decay products of electroweak bosons at HL-LHC luminosities. It is shown that available bandwidth in the proposed new strip tracker is sufficiency for a region of interest based track trigger given certain optimisations, further methods for improving upon the proposal are discussed.

Upgrade of the ATLAS Muon System for the HL-LHC

CERN Document Server

Amelung, Christoph; The ATLAS collaboration

2018-01-01

The muon spectrometer of the ATLAS detector will be significantly upgraded during the Phase-II upgrade in Long Shutdown 3 in order to cope with the operational conditions at the High-Luminosity LHC in Run 4 and beyond. Most of the electronics for the Resistive Plate Chambers (RPC), Thin Gap Chambers (TGC), and Monitored Drift Tube (MDT) chambers will be replaced to make them compatible with the higher trigger rates and longer latencies necessary for the new level-0 trigger. The MDT chambers will be integrated into the level-0 trigger in order to sharpen the momentum threshold. Additional RPC chambers will be installed in the inner barrel layer to increase the acceptance and robustness of the trigger. Some of the MDT chambers in the inner barrel layer will be replaced with new small-diameter MDTs. New TGC triplet chambers in the barrel-endcap transition region will replace the current TGC doublets to suppress the high trigger rate from random coincidences in this region. The power system for the RPC, TGC, and ...

Physics performances with the new ATLAS Level-1 Topological trigger in the LHC High-Luminosity Era

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00414333; The ATLAS collaboration

2016-01-01

The ATLAS trigger system aim at reducing the 40 MHz protons collision event rate to a manageable event storage rate of 1 kHz, preserving events with valuable physics meaning. The Level-1 trigger is the first rate-reducing step in the ATLAS trigger system, with an output rate of 100 kHz and decision latency of less than 2.5 micro seconds. It is composed of the calorimeter trigger, muon trigger and central trigger processor. During the last upgrade, a new electronics element was introduced to Level-1: L1Topo, the Topological Processor System. It will make it possible to use detailed realtime information from the Level-1 calorimeter and muon triggers, processed in individual state of the art FPGA processors to determine angles between jets and/or leptons and calculate kinematic variables based on lists of selected/sorted objects. Over hundred VHDL algorithms are producing trigger outputs to be incorporated into the central trigger processor. Such information will be essential to improve background rejection and ...

The ATLAS cryostat comes into the lime-light

CERN Multimedia

2002-01-01

Jean-Jacques Aubert, director of IN2P3, addresses the teams involved in the ATLAS electromagnetic calorimeter. At the rear, the barrel cryostat being equipped. In response to an invitation from IN2P3, the French national institute for nuclear and particle physics, the ATLAS experiment teams have celebrated progress made in the construction of their Liquid Argon Detector. In particular they wanted to salute the arrival of the cryostat for one of the end-caps, built by the company Simic in Italy. The second is expected at the end of January 2003. The cryostats are the fruit of a collaboration between IN2P3, the Max Planck Institute in Munich and the German Ministry for education and research (BMBF). The barrel cryostat arrived from Japan last year. The three cryostats will contain four types of different detectors made by the collaboration. They will contain in total nearly 400 modules including electromagnetic modules. More than half the modules for one of the two electromagnetic calorimeter barrels have bee...

The Normal Zone Propagation in ATLAS B00 Model Coil

NARCIS (Netherlands)

Boxman, E.W.; Dudarev, A.V.; ten Kate, Herman H.J.

2002-01-01

The B00 model coil has been successfully tested in the ATLAS Magnet Test Facility at CERN. The coil consists of two double pancakes wound with aluminum stabilized cables of the barrel- and end-cap toroids conductors for the ATLAS detector. The magnet current is applied up to 24 kA and quenches are

Thermo-dynamical measurements for ATLAS Inner Detector (evaporative cooling system)

CERN Document Server

Bitadze, Alexander; Buttar, Craig

During the construction, installation and initial operation of the Evaporative Cooling System for the ATLAS Inner Detector SCT Barrel Sub-detector, some performance characteristics were observed to be inconsistent with the original design specifications, therefore the assumptions made in the ATLAS Inner Detector TDR were revisited. The main concern arose because of unexpected pressure drops in the piping system from the end of the detector structure to the distribution racks. The author of this theses made a series of measurements of these pressure drops and the thermal behavior of SCT-Barrel cooling Stave. Tests were performed on the installed detector in the pit, and using a specially assembled full scale replica in the SR1 laboratory at CERN. This test setup has been used to perform extensive tests of the cooling performance of the system including measurements of pressure drops in different parts of system, studies of the thermal profile along the stave pipe for different running conditions / parameters a...

Status of the ATLAS Liquid Argon Calorimeter and its Performance

CERN Document Server

Barillari, T; The ATLAS collaboration

2011-01-01

The ATLAS experiment is designed to study the proton-proton collisions produced at the LHC with a centre-of-mass energy of 14 TeV. Liquid argon (LAr) sampling calorimeters are used in ATLAS for all electromagnetic calorimetry covering the pseudorapidity region |eta|<3.2, as well as for hadronic calorimetry from |eta|=1.4 to |eta|=4.8. The calorimeter system consists of an electromagnetic barrel calorimeter and two endcaps with electromagnetic (EMEC), hadronic (HEC) and forward (FCAL) calorimeters. The lead-liquid argon sampling technique with an accordion geometry was chosen for the barrel electromagnetic calorimeter (EMB) and adapted to the endcap (EMEC). This geometry allows a uniform acceptance over the whole azimuthal range without any gap. The hadronic endcap calorimeter (HEC) uses a copper-liquid argon sampling technique with plate geometry and is subdivided into two wheels in depth per end-cap. Finally, the forward calorimeter (FCAL) is composed of three modules featuring cylindrical electrodes ...

Influence of the botanical origin and toasting level on the ellagitannin content of wines aged in new and used oak barrels.

Science.gov (United States)

Navarro, María; Kontoudakis, Nikolaos; Gómez-Alonso, Sergio; García-Romero, Esteban; Canals, Joan Miquel; Hermosín-Gutíerrez, Isidro; Zamora, Fernando

2016-09-01

The influence of the botanical origin (French oak: Quercus petraea and American oak: Quercus alba) and different toasting levels (light, medium and heavy) on the ellagitannin content of wines aged in oak barrels has been studied. This took place in two consecutive vintages in order to study what happens after the barrels have been already used for one year with another wine. This study was carried out with two red wines (Cabernet Sauvignon) and with two decolored white wines (Macabeo) from vintages 2012 and 2013 in order to work with a simpler matrix which facilitates chemical analysis. The results show that the botanical origin, toasting level and the number of times that the barrels have been used exert a major influence on the final ellagitannin concentration. In general, the behavior of all the individual ellagitannins was very similar to that described for the total ellagitannins. Briefly, the levels of total ellagitannins concentration in the decolored white wine aged for 12months in new French barrels ranged between 31.2mg/L in the lightly toasted and 4.7mg/L in the heavy toasted. In contrast, these levels were quite lower in American new barrels ranging between 3.6mg/L and 0.9mg/L. Finally, the total ellagitannin concentration decreased an average of 63% in the wines aged in the one year used barrels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electrical performance of ATLAS-SCT KB end-cap modules

CERN Document Server

D'Onofrio, M; Donegà, M; Ferrère, D; Mangin-Brinet, M; Mikulec, B; Weber, M; Ikegami, Y; Kohriki, T; Kondo, T; Terada, S; Unno, Y; Pernegger, H; Roe, S; Wallny, R; Moorhead, G F; Taylor, G; García, J E; Gonzáles, S; Vos, M A; Toczek, B

2003-01-01

The Semiconductor Tracker (SCT) is one of the ATLAS Inner Detector elements which aims to track charged particles in the ATLAS experiment. It consists of four cylindrical layers (barrels) of silicon strip detectors, with nine disks in each of the forward and backward directions. Carbon fibre structures will support a total of 4088 modules, which are the basic functional sub-unit of the SCT. Each module consists of single sided silicon micro-strip detectors glued back to back with a 40 mrad stereo-angle, and attached to a hybrid. The scope of this document is to present the electrical performances of prototype end-cap modules proposed for the ATLAS-SCT, as an alternative to the baseline. The layout of these modules is based on the implementation of the barrel module hybrid in the end-cap geometry. A complete set of electrical measurements is summarized in this paper, including irradiated module tests and beam tests.

ATLAS Review Office

CERN Multimedia

Szeless, B

The ATLAS internal reviews, be it the mandatory Production Readiness Reviews, the now newly installed Production Advancement Reviews, or the more and more requested different Design Reviews, have become a part of our ATLAS culture over the past years. The Activity Systems Status Overviews are, for the time being, a one in time event and should be held for each system as soon as possible to have some meaning. There seems to a consensus that the reviews have become a useful project tool for the ATLAS management but even more so for the sub-systems themselves making achievements as well as possible shortcomings visible. One other recognized byproduct is the increasing cross talk between the systems, a very important ingredient to make profit all the systems from the large collective knowledge we dispose of in ATLAS. In the last two months, the first two PARs were organized for the MDT End Caps and the TRT Barrel Modules, both part of the US contribution to the ATLAS Project. Furthermore several different design...

Response sensitivity of barrel neuron subpopulations to simulated thalamic input.

Science.gov (United States)

Pesavento, Michael J; Rittenhouse, Cynthia D; Pinto, David J

2010-06-01

Our goal is to examine the relationship between neuron- and network-level processing in the context of a well-studied cortical function, the processing of thalamic input by whisker-barrel circuits in rodent neocortex. Here we focus on neuron-level processing and investigate the responses of excitatory and inhibitory barrel neurons to simulated thalamic inputs applied using the dynamic clamp method in brain slices. Simulated inputs are modeled after real thalamic inputs recorded in vivo in response to brief whisker deflections. Our results suggest that inhibitory neurons require more input to reach firing threshold, but then fire earlier, with less variability, and respond to a broader range of inputs than do excitatory neurons. Differences in the responses of barrel neuron subtypes depend on their intrinsic membrane properties. Neurons with a low input resistance require more input to reach threshold but then fire earlier than neurons with a higher input resistance, regardless of the neuron's classification. Our results also suggest that the response properties of excitatory versus inhibitory barrel neurons are consistent with the response sensitivities of the ensemble barrel network. The short response latency of inhibitory neurons may serve to suppress ensemble barrel responses to asynchronous thalamic input. Correspondingly, whereas neurons acting as part of the barrel circuit in vivo are highly selective for temporally correlated thalamic input, excitatory barrel neurons acting alone in vitro are less so. These data suggest that network-level processing of thalamic input in barrel cortex depends on neuron-level processing of the same input by excitatory and inhibitory barrel neurons.

Response and Shower Topology of 2 to 180 GeV Pions Measured with the ATLAS Barrel Calorimeter at the CERN Test-beam and Comparison to Monte Carlo Simulations

CERN Document Server

Abat, E; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Alexa, C; Anderson, K; Andreazza, A; Anghinolfi, F; Antonaki, A; Arabidze, G; Arik, E; Atkinson, T; Baines, J; Baker, O K; Banfi, D; Baron, S; Barr, A J; Beccherle, R; Beck, H P; Belhorma, B; Bell, P J; Benchekroun, D; Benjamin, D P; Benslama, K; Bergeaas Kuutmann, E; Bernabeu, J; Bertelsen, H; Binet, S; Biscarat, C; Boldea, V; Bondarenko, V G; Boonekamp, M; Bosman, M; Bourdarios, C; Broklova, Z; Burckhart Chromek, D; Bychkov, V; Callahan, J; Calvet, D; Canneri, M; Capeans Garrido, M; Caprini, M; Cardiel Sas, L; Carli, T; Carminati, L; Carvalho, J; Cascella, M; Castillo, M V; Catinaccio, A; Cauz, D; Cavalli, D; Cavalli Sforza, M; Cavasinni, V; Cetin, S A; Chen, H; Cherkaoui, R; Chevalier, L; Chevallier, F; Chouridou, S; Ciobotaru, M; Citterio, M; Clark, A; Cleland, B; Cobal, M; Cogneras, E; Conde Muino, P; Consonni, M; Constantinescu, S; Cornelissen, T; Correard, S; Corso Radu, A; Costa, G; Costa, M J; Costanzo, D; Cuneo, S; Cwetanski, P; Da Silva, D; Dam, M; Dameri, M; Danielsson, H O; Dannheim, D; Darbo, G; Davidek, T; De, K; Defay, P O; Dekhissi, B; Del Peso, J; Del Prete, T; Delmastro, M; Derue, F; Di Ciaccio, L; Dita, S; Dittus, F; Djama, F; Djobava, T; Dobos, D; Dobson, M; Dolgoshein, B A; Dotti, A; Drake, G; Drasal, Z; Dressnandt, N; Driouchi, G; Drohan, J; Ebenstein, W L; Eerola, P; Eerola, P; Efthymiopoulos, I; Egorov, K; Eifert, T F; Einsweiler, K; El Kacimi, M; Elsing, M; Emelyanov, D; Escobar, C; Etienvre, A I; Fabich, A; Facius, K; Fakhr-Edine, A I; Fanti, M; Farbin, A; Farthouat, P; Fassouliotis, D; Fayard, L; Febbraro, R; Fedin, O L; Fenyuk, A; Fergusson, D; Ferrari, P; Ferrari, R; Ferreira, B C; Ferrer, A; Ferrere, D; Filippini, G; Flick, T; Fournier, D; Francavilla, P; Francis, D; Froeschl, R; Froidevaux, D; Fullana, E; Gadomski, S; Gagliardi, G; Gagnon, P; Gallas, M; Gallop, B J; Gameiro, S; Gan, K K; Garcia, R; Garcia, C; Gavrilenko, I L; Gemme, C; Gerlach, P; Ghodbane, N; Giakoumopoulou, V; Giangiobbe, V; Giokaris, N; Di Girolamo, B; Glonti, G; Goettfert, T; Golling, T; Gollub, N; Gomes, A; Gomez, M D; Gonzalez-Sevilla, S; Goodrick, M J; Gorfine, G; Gorini, B; Goujdami, D; Grahn, K J; Grenier, P; Grigalashvili, N; Grishkevich, Y; Grosse-Knetter, J; Gruwe, M; Guicheney, C; Gupta, A; Haeberli, C; Haertel, R; Hajduk, Z; Hakobyan, H; Hance, M; Hansen, D J; Hansen, P H; Hara, K; Harvey Jr, A; Hawkings, R J; Heinemann, F E W; Henriques Correia, A; Henss, T; Hervas, L; Higon, E; Hill, J C; Hoffman, J; Hostachy, J Y; Hruska, I; Hubaut, F; Huegging, F; Hulsbergen, W; Hurwitz, M; Iconomidou-Fayard, L; Jansen, E; Jen-La Plante, I; Johansson, P D C; Jon-And, K; Joos, M; Jorgensen, S; Joseph, J; Kaczmarska, A; Kado, M; Karyukhin, A; Kataoka, M; Kayumov, F; Kazarov, A; Keener, P T; Kekelidze, G D; Kerschen, N; Kersten, S; Khomich, A; Khoriauli, G; Khramov, E; Khristachev, A; Khubua, J; Kittelmann, T H; Klingenberg, R; Klinkby, E B; Kodys, P; Koffas, T; Kolos, S; Konovalov, S P; Konstantinidis, N; Kopikov, S; Korolkov, I; Kostyukhin, V; Kovalenko, S; Kowalski, T Z; Kruger, K; Kramarenko, V; Kudin, L G; Kulchitsky, Y; Le Bihan, A C; Lacasta, C; Lafaye, R; Laforge, B; Lampl, W; Lanni, F; Laplace, S; Lari, T; Latorre, S; Le Bihan, A C; Lechowski, M; Ledroit-Guillon, F; Lehmann, G; Leitner, R; Lelas, D; Lester, C G; Liang, Z; Lichard, P; Liebig, W; Lipniacka, A; Lokajicek, M; Louchard, L; Lourerio, K F; Lucotte, A; Luehring, F; Lund-Jensen, B; Lundberg, B; Ma, H; Mackeprang, R; Maio, A; Maleev, V P; Malek, F; Mandelli, L; Maneira, J; Mangin-Brinet, M; Manousakis, A; Mapelli, L; Marques, C; Marti i García, S; Martin, F; Mathes, M; Mazzanti, M; McFarlane, K W; McPherson, R; Mchedlidze, G; Mehlhase, S; Meirosu, C; Meng, Z; Meroni, C; Miagkov, A; Mialkovski, V; Mikulec, B; Milstead, D; Minashvili, I; Mindur, B; Mitsou, V A; Moed, S; Monnier, E; Moorhead, G; Morettini, P; Morozov, S V; Mosidze, M; Mouraviev, S V; Moyse, E W J; Munar, A; Nadtochi, A V; Nakamura, K; Nechaeva, P; Negri, A; Nemecek, S; Nessi, M; Nesterov, S Y; Newcomer, F M; Nikitine, I; Nikolaev, K; Nikolic-Audit, I; Ogren, H; Oh, S H; Oleshko, S B; Olszowska, J; Onofre, A; Padilla Aranda, C; Paganis, S; Pallin, D; Pantea, D; Paolone, V; Parodi, F; Parsons, J; Parzhitskiy, S; Pasqualucci, E; Passmore, M S; Pater, J; Patrichev, S; Peez, M; Perez Reale, V; Perini, L; Peshekhonov, V D; Petersen, J; Petersen, T C; Petti, R; Phillips, P W; Pilcher, J; Pina, J; Pinto, B; Podlyski, F; Poggioli, L; Poppleton, A; Poveda, J; Pralavorio, P; Pribyl, L; Price, M J; Prieur, D; Puigdengoles, C; Puzo, P; Rohne, O; Ragusa, F; Rajagopalan, S; Reeves, K; Reisinger, I; Rembser, C; Bruckman de Renstrom, P; Reznicek, P; Ridel, M; Risso, P; Riu, I; Robinson, D; Roda, C; Roe, S; Romaniouk, A; Rousseau, D; Rozanov, A; Ruiz, A; Rusakovich, N; Rust, D; Ryabov, Y F; Ryjov, V; Salto, O; Salvachua, B; Salzburger, A; Sandaker, H; Santamarina Rios, C; Santi, L; Santoni, C; Saraiva, J G; Sarri, F; Sauvage, G; Says, L P; Schaefer, M; Schegelsky, V A; Schiavi, C; Schieck, J; Schlager, G; Schlereth, J; Schmitt, C; Schultes, J; Schwemling, P; Schwindling, J; Seixas, J M; Seliverstov, D M; Serin, L; Sfyrla, A; Shalanda, N; Shaw, C; Shin, T; Shmeleva, A; Silva, J; Simion, S; Simonyan, M; Sloper, J E; Smirnov, S Yu; Smirnova, L; Solans, C; Solodkov, A; Solovianov, O; Soloviev, I; Sosnovtsev, V V; Spano, F; Speckmayer, P; Stancu, S; Stanek, R; Starchenko, E; Straessner, A; Suchkov, S I; Suk, M; Szczygiel, R; Tarrade, F; Tartarelli, F; Tas, P; Tayalati, Y; Tegenfeldt, F; Teuscher, R; Thioye, M; Tikhomirov, V O; Timmermans, C; Tisserant, S; Toczek, B; Tremblet, L; Troncon, C; Tsiareshka, P; Tyndel, M; Karagoez Unel, M; Unal, G; Unel, G; Usai, G; Van Berg, R; Valero, A; Valkar, S; Valls, J A; Vandelli, W; Vannucci, F; Vartapetian, A; Vassilakopoulos, V I; Vasilyeva, L; Vazeille, F; Vernocchi, F; Vetter-Cole, Y; Vichou, I; Vinogradov, V; Virzi, J; Vivarelli, I; De Vivie, J B; Volpi, M; Vu Anh, T; Wang, C; Warren, M; Weber, J; Weber, M; Weidberg, A R; Weingarten, J; Wells, P S; Werner, P; Wheeler, S; Wiessmann, M; Wilkens, H; Williams, H H; Wingerter-Seez, I; Yasu, Y; Zaitsev, A; Zenin, A; Zenis, T; Zenonos, Z; Zhang, H; Zhelezko, A; Zhou, N

2010-01-01

The response of the ATLAS barrel calorimeter to pions with momenta from $2$ to $180$~GeV~ is studied in a test--beam at the CERN H8 beam line. %Various methods to reconstruct the deposited pion energies are studied. The mean energy, the energy resolution and the longitudinal and radial shower profiles, and, various observables characterising the shower topology in the calorimeter are measured. The data are compared to Monte Carlo simulations based on a detailed description of the experimental set--up and on various models describing the interaction of particles with matter based on Geant4.

Progress on the development of a detector mounted analog and digital readout system for the ATLAS TRT

CERN Document Server

Baxter, C; Dressnandt, N; Gay, C; Lundberg, B; Munar, A; Mayers, G; Newcomer, M; Van Berg, R; Williams, H H

2004-01-01

The 430,000 element ATLAS Transition Radiation straw tube Tracker (TRT) is divided into a central barrel tracker consisting of 104,000 axially mounted straws and two radially arranged end caps on either side of the barrel with 160,000 straws each. To achieve a track position resolution of 140 mu m, the front end electronics must operate at a low (2fC) threshold with a time marking capability of ~1ns. Two ASICs, the ASDBLR and DTMROC provide the complete pipelined readout chain. Custom designed FBGA packages for the ASICs provide a small enough outline to be detector mounted and the extensive use of low level differential signals make mounting the analog packages on printed circuit boards directly opposite the 40 MHz digital chips feasible. The readout electronics for the barrel occupies a potentially important part of the active tracker volume and an aggressive effort has been made to make it as compact as possible. Utilizing a single board for both analog and digital ASICS a 0.1 cm /sup 3/ per channel volume...

The Topological Processor for the future ATLAS Level-1 Trigger: from design to commissioning

CERN Document Server

Simioni, E; The ATLAS collaboration

2014-01-01

The ATLAS detector at the Large Hadron Collider (LHC) is designed to measure decay properties of high energetic particles produced in the proton-proton collisions. During its first run, the LHC collided proton bunches at a frequency of 20 MHz, and therefore the detector required a Trigger system to efficiently select events down to a manageable event storage rate of about 400 Hz. By 2015 the LHC instantaneous luminosity will be increased up to 3$\\times$$10^{34}cm^{-2}s^{-1}$: this represent an unprecedented challenge faced by the ATLAS Trigger system. To cope with the higher event rate and efficiently select relevant events from physics point of view, a new element will be included in the Level-1 Trigger scheme after 2015: the Topological Processor (L1Topo).\\\\ The L1Topo system, currently developed at CERN, will consist initially of an ATCA crate and two L1Topo modules. A high density opto-electroconverter (AVAGO miniPOD) drives up to 1.6 Tb/s of data from the calorimeter and muon detectors into two high end ...

Tests and final integration of the ATLAS semiconductor tracker

CERN Document Server

Mikulec, Bettina

2005-01-01

The Silicon Tracker (SCT) is part of the Inner Detector at the ATLAS experiment at CERN. Its basic building blocks are 5 different types of silicon strip modules. In total more than 15000 p-on-n single-sided silicon strip sensors of an area of about 61 m2 were used to produce 4088 SCT modules. An overall module production yield of 92% could be achieved, where the silicon modules comply with the tight electrical, thermal and mechanical specifications. The macro-assembly of 2112 barrel modules to the four barrel support cylinders was successfully carried out. The nine disks of one endcap are fully populated with 988 modules, and for the second endcap more than 50% of the modules are already mounted. Test results operating complete barrels will be presented as well as a description of the test setup. The different integration steps of the SCT with the surrounding Transition Radiation Tracker (TRT) will be explained. The installation of SCT and TRT into the ATLAS pit will happen during 2006.

Staves and Petals: Multi-module Local Support Structures of the ATLAS ITk Strips Upgrade

CERN Document Server

Rodriguez Rodriguez, Daniel; The ATLAS collaboration

2017-01-01

The ATLAS Inner Tracker (ITk) is an all-silicon tracker that will replace the existing inner detector at the Phase-II Upgrade of ATLAS. The outermost part of the tracker consists of the strips tracker, in which the sensor elements consist of silicon micro-strip sensors with strip lengths varying from 1.7 to up to 10 cm. The current design is part of the ATLAS ITk Strip Detector Technical Design Report (TDR) and envisions a four-layer barrel and two six-disk end-cap regions. The sensor and readout units (``modules'') are directly glued onto multi-module, low-mass, high thermal performance carbon fibre structures, called “staves” for the barrel and ``petals'' for the end-cap. They provide cooling, power, data and control lines to the modules with a minimal amount of external services. An extensive prototyping program was put in place over the last years to fully characterise these structures mechanically, thermally, and electrically. Thermo-mechanical stave and petal prototypes have recently been built and ...

Upgrades of the ATLAS Muon Spectrometer with sMDT Chambers

CERN Document Server

Ferretti, Claudio; The ATLAS collaboration

2015-01-01

With half the drift-tube diameter of the Monitored Drift Tube (MDT) chambers of the ATLAS muon spectrometer and otherwise unchanged operating parameters, small-diameter Muon Drift Tube (sMDT) chambers provide an order of magnitude higher rate capability and can be installed in detector regions where MDT chambers do not fit. The chamber assembly time has been reduced by a factor of seven to one working day and the sense wire positioning accuracy improved by a factor of two to better than ten microns. Two sMDT chambers have been installed in ATLAS in 2014 to improve the momentum resolution in the barrel part of the spectrometer. The construction of additional twelve chambers covering the feet regions of the ATLAS detector has started. It will be followed by the replacement of the MDT chambers at the ends of the barrel inner layer by sMDTs improving the Performance at the high expected background rates and providing space for additional RPC trigger chambers.

Upgrades of the ATLAS Muon Spectrometer with sMDT Chambers

CERN Document Server

Ferretti, C

2016-01-01

With half the drift-tube diameter of the Monitored Drift Tube (MDT) chambers of the ATLAS muon spectrometer and otherwise unchanged operating parameters, small-diameter Muon Drift Tube (sMDT) chambers provide an order of magnitude higher rate capability and can be installed in detector regions where MDT chambers do not fit. The chamber assembly time has been reduced by a factor of seven to one working day and the sense wire positioning accuracy improved by a factor of two to better than ten microns. Two sMDT chambers have been installed in ATLAS in 2014 to improve the momentum resolution in the barrel part of the spectrometer. The construction of an additional twelve chambers covering the feet regions of the ATLAS detector has started. It will be followed by the replacement of the MDT chambers at the ends of the barrel inner layer by sMDTs improving the Performance at the high expected background rates and providing space for additional RPC trigger chambers.

Instrumentation of a Level-1 Track Trigger at ATLAS with Double Buffer Front-End Architecture

CERN Document Server

Cooper, B; The ATLAS collaboration

2012-01-01

The increased collision rate and pile-up produced at the HLLHC requires a substantial upgrade of the ATLAS level-1 trigger in order to maintain a broad physics reach. We show that tracking information can be used to control trigger rates, and describe a proposal for how this information can be extracted within a two-stage level-1 trigger design that has become the baseline for the HLLHC upgrade. We demonstrate that, in terms of the communication between the external processing and the tracking detector frontends, a hardware solution is possible that fits within the latency constraints of level-1.

ATLAS Level-1 Topological Trigger : Commissioning and Validation in Run 2

CERN Document Server

AUTHOR|(SzGeCERN)788741; The ATLAS collaboration; Hong, Tae Min

2017-01-01

The ATLAS experiment has recently commissioned a new hardware component of its first-level trigger: the topological processor (L1Topo). This innovative system, using state-of-the-art FPGA processors, selects events by applying kinematic and topological requirements on candidate objects (energy clusters, jets, and muons) measured by calorimeters and muon sub-detectors. Since the first-level trigger is a synchronous pipelined system, such requirements are applied within a latency of 200ns. We will present the first results from data recorded using the L1Topo trigger; these demonstrate a significantly improved background event rejection, thus allowing for a rate reduction without efficiency loss. This improvement has been shown for several physics processes leading to low-$P_{T}$ leptons, including $H\\to{}\\tau{}\\tau{}$ and $J/\\Psi\\to{}\\mu{}\\mu{}$. In addition, we will discuss the use of an accurate L1Topo simulation as a powerful tool to validate and optimize the performance of this new trigger system. To reach ...

The Phase-1 Upgrade of the ATLAS First Level Calorimeter Trigger

CERN Document Server

Andrei, George Victor; The ATLAS collaboration

2017-01-01

The ATLAS Level-1 calorimeter trigger is planning a series of upgrades in order to face the challenges posed by the upcoming increase of the LHC luminosity. The hardware built for the Phase-1 upgrade will be installed during the long shutdown of the LHC starting in 2019, with the aim of being fully commissioned before the restart in 2021. The upgrade will benefit from new front end electronics for parts of the calorimeter which provide the trigger system with digital data with a tenfold increase in granularity. This makes possible the use of more complex algorithms than currently used and while maintaining low trigger thresholds under much harsher collision conditions. Of principal significance among these harsher conditions will be the increased number interactions per bunch crossing, known as pile-up. The Level-1 calorimeter system upgrade consists of an active and a passive system for digital data distribution and three different Feature EXtraction systems (FEXs) which run complex algorithms to identify el...

The ATLAS High Level Trigger Steering Framework and the Trigger 
Configuration System.

CERN Document Server

Pérez Cavalcanti, Tiago; The ATLAS collaboration

2011-01-01

The ATLAS High Level Trigger Steering Framework and the Trigger 
Configuration System.
 
The ATLAS detector system installed in the Large Hadron Collider (LHC) 
at CERN is designed to study proton-proton and nucleus-nucleus 
collisions with a maximum center of mass energy of 14 TeV at a bunch 
collision rate of 40MHz.  In March 2010 the four LHC experiments saw 
the first proton-proton collisions at 7 TeV. Still within the year a 
collision rate of nearly 10 MHz is expected. At ATLAS, events of 
potential interest for ATLAS physics are selected by a three-level 
trigger system, with a final recording rate of about 200 Hz. The first 
level (L1) is implemented in custom hardware; the two levels of 
the high level trigger (HLT) are software triggers, running on large 
farms of standard computers and network devices. 

Within the ATLAS physics program more than 500 trigger signatures are 
defined. The HLT tests each signature on each L1-accepted event; the 
test outcome is recor...

Development of the SSTL-300-S1 Composite Imager Barrel Structure

Science.gov (United States)

Hamar, Chris; Wood, Trevor; Alsami, Sami; Hallett, Ben

2014-06-01

The SSTL-300-S1 is the latest in the family of highly capable SSTL-300 platforms, providing high resolution imagery with all the existing mission performance of the heritage platform. In developing the product, SSTL has had to undertake the development of a composite imager barrel assembly, which forms the payload instrument's primary structure. Working to a nominal schedule of 24 months from requirements definition to structural qualification, the barrel's development philosophy has had to carefully balance the interdependent optical, structural and programmatic requirements. This paper provides a brief summary description of that development.

ATLAS RPC performance on a dedicated cosmic ray test-stand

International Nuclear Information System (INIS)

Liberti, B.; Aielli, G.; Camarri, P.; Cardarelli, R.; Corradi, M.; Di Ciaccio, A.; Di Stante, L.; Palummo, L.; Pastori, E.; Salamon, A.; Santonico, R.; Solfaroli, E.

2008-01-01

596 RPC chambers have been assembled in the ATLAS Muon Spectrometer, covering a 7300 m 2 sensitive area with 355.000 read out channels. 1116 RPC Units were produced and tested before integration and installation on the experiment [A. Aloisio et al., 'The trigger chambers of the ATLAS muon spectrometer: production and tests', Nuclear Instruments and Methods A535 (2004) 265-271]. 192 ATLAS RPCs, the Barrel Outer Large (BOL) units were tested in INFN Roma Tor Vergata test stand

The ATLAS level-1 trigger: Status of the system and first results from cosmic-ray data

Energy Technology Data Exchange (ETDEWEB)

Aielli, G [Universita degli Studi di Roma ' Tor Vergata' and INFN Roma II, Rome (Italy); Andrei, V; Achenbach, R [Kirchhoff-Institut fuer Physik, University of Heidelberg, D-69120 Heidelberg (Germany); Adragna, P [Physics Department, Queen Mary, University of London, London E1 4NS (United Kingdom); Aloisio, A; Alviggi, M G [Universita degli Studi di Napoli ' Federico II' and INFN Napoli (Italy); Antonelli, S [INFN Bologna and Universita degli Studi di Bologna (Italy); Ask, S [CERN, PH Department (Switzerland); Barnett, B M [CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Bauss, B [Institut fuer Physik, University of Mainz, D-55099 Mainz (Germany); Bellagamba, L [INFN Bologna and Universita degli Studi di Bologna (Italy); Ben Ami, S [Technion Israel Institute of Technology (Israel); Bendel, M [Institut fuer Physik, University of Mainz, D-55099 Mainz (Germany); Benhammou, Y [Tel Aviv University (Israel); Berge, D. [CERN, PH Department (Switzerland)], E-mail: David.Berge@cern.ch; Bianco, M [Universita degli Studi di Lecce and INFN Lecce (Italy); Biglietti, M G [Universita degli Studi di Napoli ' Federico II' and INFN Napoli (Italy); Bohm, C [Fysikum, University of Stockholm, SE-10691 Stockholm (Sweden); Booth, J R.A. [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom); CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Boscherini, D [INFN Bologna and Universita degli Studi di Bologna (Italy)

2007-10-21

The ATLAS detector at CERN's Large Hadron Collider (LHC) will be exposed to proton-proton collisions from beams crossing at 40 MHz. At the design luminosity of 10{sup 34}cm{sup -2}s{sup -1} there are on average 23 collisions per bunch crossing. A three-level trigger system will select potentially interesting events in order to reduce the readout rate to about 200 Hz. The first trigger level is implemented in custom-built electronics and makes an initial fast selection based on detector data of coarse granularity. It has to reduce the rate by a factor of 10{sup 4} to less than 100 kHz. The other two consecutive trigger levels are in software and run on PC farms. We present an overview of the first-level trigger system and report on the current installation status. Moreover, we show analysis results of cosmic-ray data recorded in situ at the ATLAS experimental site with final or close-to-final hardware.

The ATLAS level-1 trigger: Status of the system and first results from cosmic-ray data

International Nuclear Information System (INIS)

Aielli, G.; Andrei, V.; Achenbach, R.; Adragna, P.; Aloisio, A.; Alviggi, M.G.; Antonelli, S.; Ask, S.; Barnett, B.M.; Bauss, B.; Bellagamba, L.; Ben Ami, S.; Bendel, M.; Benhammou, Y.; Berge, D.; Bianco, M.; Biglietti, M.G.; Bohm, C.; Booth, J.R.A.; Boscherini, D.

2007-01-01

The ATLAS detector at CERN's Large Hadron Collider (LHC) will be exposed to proton-proton collisions from beams crossing at 40 MHz. At the design luminosity of 10 34 cm -2 s -1 there are on average 23 collisions per bunch crossing. A three-level trigger system will select potentially interesting events in order to reduce the readout rate to about 200 Hz. The first trigger level is implemented in custom-built electronics and makes an initial fast selection based on detector data of coarse granularity. It has to reduce the rate by a factor of 10 4 to less than 100 kHz. The other two consecutive trigger levels are in software and run on PC farms. We present an overview of the first-level trigger system and report on the current installation status. Moreover, we show analysis results of cosmic-ray data recorded in situ at the ATLAS experimental site with final or close-to-final hardware

The ATLAS High Level Trigger Steering Framework and the Trigger Configuration System.

CERN Document Server

Perez Cavalcanti, Tiago; The ATLAS collaboration

2011-01-01

The ATLAS detector system installed in the Large Hadron Collider (LHC) at CERN is designed to study proton-proton and nucleus-nucleus collisions with a maximum centre of mass energy of 14 TeV at a bunch collision rate of 40MHz. In March 2010 the four LHC experiments saw the first proton-proton collisions at 7 TeV. Still within the year a collision rate of nearly 10 MHz is expected. At ATLAS, events of potential interest for ATLAS physics are selected by a three-level trigger system, with a final recording rate of about 200 Hz. The first level (L1) is implemented in custom hardware; the two levels of the high level trigger (HLT) are software triggers, running on large farms of standard computers and network devices. Within the ATLAS physics program more than 500 trigger signatures are defined. The HLT tests each signature on each L1-accepted event; the test outcome is recorded for later analysis. The HLT-Steering is responsible for this. It foremost ensures the independent test of each signature, guarantying u...

Towards a Level-1 Tracking Trigger for the ATLAS Experiment

CERN Document Server

De Santo, A; The ATLAS collaboration

2014-01-01

Plans for a physics-driven upgrade of the LHC foresee staged increases of the accelerator's average instantaneous luminosity, of up to a factor of five compared to the original design. In order to cope with the sustained luminosity increase, and the resulting higher detector occupancy and particle interaction rates, the ATLAS experiment is planning phased upgrades of the trigger system and of the DAQ infrastructure. In the new conditions, maintaining an adequate signal acceptance for electro-weak processes will pose unprecedented challenges, as the default solution to cope with the higher rates would be to increase thresholds on the transverse momenta of physics objects (leptons, jets, etc). Therefore the possibility to apply fast processing at the first trigger level in order to use tracking information as early as possible in the trigger selection represents a most appealing opportunity, which can preserve the ATLAS trigger's selectivity without reducing its flexibility. Studies to explore the feasibility o...

Design and Commissioning of the ATLAS Muon Spectrometer RPC Read Out Driver

CERN Document Server

Aloisio, A; Cevenini, F; Della Pietra; Della Volpe; Izzo, V

2008-01-01

The RPC subsystem of the ATLAS muon spectrometer provides the Level-1 trigger in the barrel and it is read out by a specific DAQ system. On-detector electronics pack the RPC data in frames, tagged with an event number assigned by the trigger logic, and transmit them to the counting room on optical fibre. Data from each sector are then routed together to a Read-Out Driver (ROD) board. This is a custom processor that parses the frames, checks their coherence and builds a data structure for all the RPCs of one of the 32 sectors of the spectrometer. Each ROD sends the event fragments to a Read-Out subsystem for further event building and analysis. The ROD is a VME64x board, designed around two Xilinx Virtex-II FPGAs and an ARM7 microcontroller. In this paper we describe the board architecture and the event binding algorithm. The boards have been installed in the ATLAS USA15 control room and have been successfully used in the ATLAS commissioning runs.

The Topological Processor for the future ATLAS Level-1 Trigger: from design to commissioning

CERN Document Server

INSPIRE-00226165

2014-01-01

The ATLAS detector at LHC will require a Trigger system to efficiently select events down to a manageable event storage rate of about 400 Hz. By 2015 the LHC instantaneous luminosity will be increased up to 3 x 10^34 cm-2s-1, this represents an unprecedented challenge faced by the ATLAS Trigger system. To cope with the higher event rate and efficiently select relevant events from a physics point of view, a new element will be included in the Level-1 Trigger scheme after 2015: the Topological Processor (L1Topo). The L1Topo system, currently developed at CERN, will consist initially of an ATCA crate and two L1Topo modules. A high density opto-electroconverter (AVAGO miniPOD) drives up to 1.6 Tb/s of data from the calorimeter and muon detectors into two high-end FPGA (Virtex7-690), to be processed in about 200 ns. The design has been optimized to guarantee excellent signal in- tegrity of the high-speed links and low latency data transmission on the Real Time Data Path (RTDP). The L1Topo receives data in a standa...

Design, Construction and Installation of the ATLAS Hadronic Barrel Scintillator-Tile Calorimeter

CERN Document Server

Abdallah, J; Alexa, C; Alves, R; Amaral, P; Ananiev, A; Anderson, K; Andresen, X; Antonaki, A; Batusov, V; Bednar, P; Bergeaas, E; Biscarat, C; Blanch, O; Blanchot, G; Bohm, C; Boldea, V; Bosi, F; Bosman, M; Bromberg, C; Budagov, Yu A; Calvet, D; Cardeira, C; Carli, T; Carvalho, J; Cascella, M; Castillo, M V; Costello, J; Cavalli-Sforza, M; Cavasinni, V; Cerqueira, A S; Clément, C; Cobal, M; Cogswell, F; Constantinescu, S; Costanzo, D; Da Silva, P; Davidek, M; David, T; Dawson, J; De, K; Del Prete, T; Di Girolamo, B; Dita, S; Dolejsi, J; Dolezal, Z; Dotti, A; Downing, R; Drake, G; Efthymiopoulos, I; Errede, D; Errede, S; Farbin, A; Fassouliotis, D; Feng, E; Fenyuk, A; Ferdi, C; Ferreira, B C; Ferrer, A; Flaminio, V; Flix, J; Francavilla, P; Fullana, E; Garde, V; Gellerstedt, K; Giakoumopoulou, V; Giangiobbe, V; Gildemeister, O; Gilewsky, V; Giokaris, N; Gollub, N; Gomes, A; González, V; Gouveia, J; Grenier, P; Gris, P; Guarino, V; Guicheney, C; Sen-Gupta, A; Hakobyan, H; Haney, M; Hellman, S; Henriques, A; Higón, E; Hill, N; Holmgren, S; Hruska, I; Hurwitz, M; Huston, J; Jen-La Plante, I; Jon-And, K; Junk, T; Karyukhin, A; Khubua, J; Klereborn, J; Kopikov, S; Korolkov, I; Krivkova, P; Kulchitsky, Y; Kurochkin, Yu; Kuzhir, P; Lapin, V; Le Compte, T; Lefèvre, R; Leitner, R; Li, J; Liablin, M; Lokajícek, M; Lomakin, Y; Lourtie, P; Lovas, L; Lupi, A; Maidantchik, C; Maio, A; Maliukov, S; Manousakis, A; Marques, C; Marroquim, F; Martin, F; Mazzoni, E; Merritt, F S; Myagkov, A; Miller, R; Minashvili, I; Miralles, L; Montarou, G; Némécek, S; Nessi, M; Nikitine, I; Nodulman, L; Norniella, O; Onofre, A; Oreglia, M; Palan, B; Pallin, D; Pantea, D; Pereira, A; Pilcher, J E; Pina, J; Pinhão, J; Pod, E; Podlyski, F; Portell, X; Poveda, J; Pribyl, L; Price, L E; Proudfoot, J; Ramalho, M; Ramstedt, M; Raposeiro, L; Reis, J; Richards, R; Roda, C; Romanov, V; Rosnet, P; Roy, P; Ruiz, A; Rumiantsau, V; Russakovich, N; Sada Costa, J; Salto, O; Salvachúa, B; Sanchis, E; Sanders, H; Santoni, C; Santos, J; Saraiva, J G; Sarri, F; Says, L P; Schlager, G; Schlereth, J L; Seixas, J M; Selldén, B; Shalanda, N; Shevtsov, P; Shochet, M; Simaitis, V; Simonyan, M; Sisakian, A; Sjölin, J; Solans, C; Solodkov, A; Solovianov, J; Silva, O; Sosebee, M; Spanó, F; Speckmeyer, P; Stanek, R; Starchenko, E; Starovoitov, P; Suk, M; Sykora, I; Tang, F; Tas, P; Teuscher, R; Tokar, S; Topilin, N; Torres, J; Underwood, D; Usai, G; Valero, A; Valkár, S; Valls, J A; Vartapetian, A; Vazeille, F; Vellidis, C; Ventura, F; Vichou, I; Vivarelli, I; Volpi, M; White, A; Zaitsev, A; Zenin, A; Zenis, T; Zenonos, Z; Zenz, S; Zilka, B

2007-01-01

The scintillator tile hadronic calorimeter is a sampling calorimeter using steel as the absorber structure and scintillator as the active medium. The scintillator is located in "pockets" in the steel structure and the wavelength-shifting fibers are contained in channels running radially within the absorber to photomultiplier tubes which are located in the outer support girders of the calorimeter structure. In addition, to its role as a detector for high energy particles, the tile calorimeter provides the direct support of the liquid argon electromagnetic calorimeter in the barrel region, and the liquid argon electromagnetic and hadronic calorimeters in the endcap region. Through these, it indirectly supports the inner tracking system and beam pipe. The steel absorber, and in particular the support girders, provide the flux return for the solenoidal field from the central solenoid. Finally, the end surfaces of the barrel calorimeter are used to mount services, power supplies and readout crates for the inner tr...

Members of the Science and Technology Commission, Spanish Senate visit ATLAS

CERN Multimedia

Maximilien Brice

2002-01-01

Photo 01: Members of the Science and Technology Commission, Spanish Senate, in front of a barrel toroid cryostat vessel in the ATLAS assembly hall. The air-core ATLAS barrel toroid magnet system will consist of eight large superconducting coils, each in its own vacuum vessel, built by Spanish company Felguera Construcciones Mecanicas SA under the responsibility of IFAE (Institute for High Energy Physics), Barcelona. Standing (left to right): Dr Peter Jenni, ATLAS spokesperson; Dr Manuel Aguilar-Benitez, delegate for Spain to CERN Council; Mrs Mercedes Senen, Lawyer of the Commission; Mr Alonso Arroyo, President of the Commission; Mr Ramon Antonio Socias, Second Vice-President of the Commission; Mr Francisco Xabier Albistur, Senator; H.E. Mr Joaquin Pérez-Villaneuva Y Tovar, Ambassador, Permanent Representative of Spain to the Office of the United Nations in Geneva and other international organisations in Switzerland, Spanish delegate to CERN Council; and Miguel Gomez. Seated (left to right): Mr Adolfo Abejon...

Barrels XXX meeting report: Barrels in Baltimore.

Science.gov (United States)

Shin, Hyeyoung; Bitzidou, Malamati; Palaguachi, Fernando; Brumberg, Joshua C

2018-03-01

The Barrels meeting annually brings together researchers focused on the rodent whisker to cortical barrel system prior to the Society for Neuroscience meeting. The 2017 meeting focused on the classification of cortical interneurons, the role interneurons have in shaping brain dynamics, and finally on the circuitry underlying oral sensations. The meeting highlighted the latest advancements in this rapidly advancing field.

Simulation and Validation of the ATLAS Level-1 Topological Trigger

CERN Document Server

Bakker, Pepijn Johannes; The ATLAS collaboration

2017-01-01

The ATLAS experiment has recently commissioned a new component of its first-level trigger: the L1 topological trigger. This system, using state-of-the-art FPGA processors, makes it possible to reject events by applying topological requirements, such as kinematic criteria involving clusters, jets, muons, and total transverse energy. The data recorded using the L1Topological trigger demonstrates that this innovative trigger strategy allows for an improved rejection rate without efficiency loss. This improvement has been shown for several relevant physics processes leading to low-$p_T$ leptons, including $H\\to{}\\tau{}\\tau{}$ and $J/\\Psi\\to{}\\mu{}\\mu{}$. In addition, an accurate simulation of the L1Topological trigger is used to validate and optimize the performance of this trigger. To reach such an accuracy, this simulation must take into account the fact that the firmware algorithms are executed on a FPGA architecture, while the simulation is executed on a floating point architecture.

ATLAS TDAQ application gateway upgrade during LS1

CERN Document Server

KOROL, A; The ATLAS collaboration; BOGDANCHIKOV, A; BRASOLIN, F; CONTESCU, A C; DUBROV, S; HAFEEZ, M; LEE, C J; SCANNICCHIO, D A; TWOMEY, M; VORONKOV, A; ZAYTSEV, A

2014-01-01

The ATLAS Gateway service is implemented with a set of dedicated computer nodes to provide a fine-grained access control between CERN General Public Network (GPN) and ATLAS Technical Control Network (ATCN). ATCN connects the ATLAS online farm used for ATLAS Operations and data taking, including the ATLAS TDAQ (Trigger and Data Aquisition) and DCS (Detector Control System) nodes. In particular, it provides restricted access to the web services (proxy), general login sessions (via SSH and RDP protocols), NAT and mail relay from ATCN. At the Operating System level the implementation is based on virtualization technologies. Here we report on the Gateway upgrade during Long Shutdown 1 (LS1) period: it includes the transition to the last production release of the CERN Linux distribution (SLC6), the migration to the centralized configuration management system (based on Puppet) and the redesign of the internal system architecture.

Technical Design Report for the Phase-II Upgrade of the ATLAS Muon Spectrometer

CERN Document Server

Collaboration, ATLAS

2017-01-01

The muon spectrometer of the ATLAS detector will be significantly upgraded during the Phase-II upgrade in LS3 in order to cope with the operational conditions at the HL-LHC in Run 4 and beyond. A large fraction of the frontend and on- and off-detector readout and trigger electronics for the Resistive Plate Chambers (RPC), Thin Gap Chambers (TGC), and Monitored Drift Tube (MDT) chambers will be replaced to make them compatible with the higher trigger rates and longer latencies necessary for the new level-0 trigger. The MDT chambers will be integrated into the level-0 trigger in order to sharpen the momentum threshold. Additional RPC chambers will be installed in the inner barrel layer to increase the acceptance and robustness of the trigger, and some chambers in high-rate regions will be refurbished. Some of the MDT chambers in the inner barrel layer will be replaced with new small-diameter MDTs. New TGC triplet chambers in the barrel-endcap transition region will replace the current TGC doublets to suppress t...

Towards a Level-1 tracking trigger for the ATLAS experiment

CERN Document Server

AUTHOR|(CDS)2070911; The ATLAS collaboration

2015-01-01

Among the upgrades for the High-Luminosity LHC era, the ATLAS collaboration is studying and developing the availability of inner detector tracking information at the first level of its three- tiered event selection chain. This will provide additional flexibility and rejection power: essential ingredients in order to cope with the demanding conditions of the upgraded LHC, as well as with unforeseen bandwidth constraints. The current state of the feasibility and performances studies is discussed.

ATLAS High-Level Trigger Performance for Calorimeter-Based Algorithms in LHC Run-I

CERN Document Server

Mann, A; The ATLAS collaboration

2013-01-01

The ATLAS detector operated during the three years of the Run-I of the Large Hadron Collider collecting information on a large number of proton-proton events. One the most important results obtained so far is the discovery of one Higgs boson. More precise measurements of this particle must be performed as well as there are other very important physics topics still to be explored. One of the key components of the ATLAS detector is its trigger system. It is composed of three levels: one (called Level 1 - L1) built on custom hardware and the two others based on software algorithms - called Level 2 (L2) and Event Filter (EF) – altogether referred to as the ATLAS High Level Trigger. The ATLAS trigger is responsible for reducing almost 20 million of collisions per second produced by the accelerator to less than 1000. The L2 operates only in the regions tagged by the first hardware level as containing possible interesting physics while the EF operates in the full detector, normally using offline-like algorithms to...

Development of the new trigger processor board for the ATLAS Level-1 endcap muon trigger for Run-3

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00525035; The ATLAS collaboration

2017-01-01

The instantaneous luminosity of the LHC will be increased by up to a factor of three with respect to the original design value at Run-3 (starting 2021). The ATLAS Level-1 end-cap muon trigger in LHC Run-3 will identify muons by combining data from the Thin-Gap Chamber detector (TGC) and the New Small Wheel (NSW), which is a new detector and will be able to operate in a high background hit rate at Run-3, to suppress the Level-1 trigger rate. In order to handle data from both TGC and NSW, a new trigger processor board has been developed. The board has a modern FPGA to make use of Multi-Gigabit transceiver technology. The readout system for trigger data has also been designed with TCP/IP instead of a dedicated ASIC. This letter presents the electronics and its firmware of the ATLAS Level-1 end-cap muon trigger processor board for LHC Run-3.

Commissioning of the magnetic field in the ATLAS muon spectrometer

International Nuclear Information System (INIS)

Arnaud, M.; Bardoux, J.; Bergsma, F.; Bobbink, G.; Bruni, A.; Chevalier, L.; Ennes, P.; Fleischmann, P.; Fontaine, M.; Formica, A.; Gautard, V.; Groenstege, H.; Guyot, C.; Hart, R.; Kozanecki, W.; Iengo, P.; Legendre, M.; Nikitina, T.; Perepelkin, E.; Ponsot, P.

2008-01-01

ATLAS is a general-purpose detector at the 14 TeV proton-proton Large Hadron Collider at CERN. The muon spectrometer will operate in the magnetic field provided by a large, eight-coil barrel toroid magnet bracketed by two smaller toroidal end-caps. The toroidal field is non-uniform, with an average value of about 0.5 T in the barrel region, and is monitored using three-dimensional Hall sensors which must be accurate to ∼1 mT. The barrel coils were installed in the cavern from 2004 to 2006, and recently powered up to their nominal current. The Hall-sensor measurements are compared with calculations to validate the magnetic models, and used to reconstruct the position and shape of the coil windings. Field perturbations by the magnetic materials surrounding the muon spectrometer are found in reasonable agreement with finite-element magnetic-field simulations

Commissioning of the magnetic field in the ATLAS muon spectrometer

CERN Document Server

Arnaud, M; Bergsma, F; Bobbink, G; Bruni, A; Chevalier, L; Ennes, P; Fleischmann, P; Fontaine, M; Formica, A; Gautard, V; Groenstege, H; Guyot, C; Hart, R; Kozanecki, W; Iengo, P; Legendre, M; Nikitina, T; Perepelkin, E; Ponsot, P; Richardson, A; Vorozhtsov, A; Vorozthsov, S

2008-01-01

ATLAS is a general-purpose detector at the 14 TeV proton-proton Large Hadron Collider at CERN. The muon spectrometer will operate in the magnetic field provided by a large, eight-coil barrel toroid magnet bracketed by two smaller toroidal end-caps. The toroidal field is non-uniform, with an average value of about 0.5 T in the barrel region, and is monitored using three-dimensional Hall sensors which must be accurate to 1 mT. The barrel coils were installed in the cavern from 2004 to 2006, and recently powered up to their nominal current. The Hall-sensor measurements are compared with calculations to validate the magnetic models, and used to reconstruct the position and shape of the coil windings. Field perturbations by the magnetic materials surrounding the muon spectrometer are found in reasonable agreement with finite-element magnetic-field simulations.

Multi-Threaded Algorithms for GPGPU in the ATLAS High Level Trigger

Science.gov (United States)

Conde Muíño, P.; ATLAS Collaboration

2017-10-01

General purpose Graphics Processor Units (GPGPU) are being evaluated for possible future inclusion in an upgraded ATLAS High Level Trigger farm. We have developed a demonstrator including GPGPU implementations of Inner Detector and Muon tracking and Calorimeter clustering within the ATLAS software framework. ATLAS is a general purpose particle physics experiment located on the LHC collider at CERN. The ATLAS Trigger system consists of two levels, with Level-1 implemented in hardware and the High Level Trigger implemented in software running on a farm of commodity CPU. The High Level Trigger reduces the trigger rate from the 100 kHz Level-1 acceptance rate to 1.5 kHz for recording, requiring an average per-event processing time of ∼ 250 ms for this task. The selection in the high level trigger is based on reconstructing tracks in the Inner Detector and Muon Spectrometer and clusters of energy deposited in the Calorimeter. Performing this reconstruction within the available farm resources presents a significant challenge that will increase significantly with future LHC upgrades. During the LHC data taking period starting in 2021, luminosity will reach up to three times the original design value. Luminosity will increase further to 7.5 times the design value in 2026 following LHC and ATLAS upgrades. Corresponding improvements in the speed of the reconstruction code will be needed to provide the required trigger selection power within affordable computing resources. Key factors determining the potential benefit of including GPGPU as part of the HLT processor farm are: the relative speed of the CPU and GPGPU algorithm implementations; the relative execution times of the GPGPU algorithms and serial code remaining on the CPU; the number of GPGPU required, and the relative financial cost of the selected GPGPU. We give a brief overview of the algorithms implemented and present new measurements that compare the performance of various configurations exploiting GPGPU cards.

Building a scalable event-level metadata service for ATLAS

International Nuclear Information System (INIS)

Cranshaw, J; Malon, D; Goosens, L; Viegas, F T A; McGlone, H

2008-01-01

The ATLAS TAG Database is a multi-terabyte event-level metadata selection system, intended to allow discovery, selection of and navigation to events of interest to an analysis. The TAG Database encompasses file- and relational-database-resident event-level metadata, distributed across all ATLAS Tiers. An oracle hosted global TAG relational database, containing all ATLAS events, implemented in Oracle, will exist at Tier O. Implementing a system that is both performant and manageable at this scale is a challenge. A 1 TB relational TAG Database has been deployed at Tier 0 using simulated tag data. The database contains one billion events, each described by two hundred event metadata attributes, and is currently undergoing extensive testing in terms of queries, population and manageability. These 1 TB tests aim to demonstrate and optimise the performance and scalability of an Oracle TAG Database on a global scale. Partitioning and indexing strategies are crucial to well-performing queries and manageability of the database and have implications for database population and distribution, so these are investigated. Physics query patterns are anticipated, but a crucial feature of the system must be to support a broad range of queries across all attributes. Concurrently, event tags from ATLAS Computing System Commissioning distributed simulations are accumulated in an Oracle-hosted database at CERN, providing an event-level selection service valuable for user experience and gathering information about physics query patterns. In this paper we describe the status of the Global TAG relational database scalability work and highlight areas of future direction

Control, Test and Monitoring Software Framework for the ATLAS Level-1 Calorimeter Trigger

CERN Document Server

Achenbach, R; Aharrouche, M; Andrei, V; Åsman, B; Barnett, B M; Bauss, B; Bendel, M; Bohm, C; Booth, J R A; Bracinik, J; Brawn, I P; Charlton, D G; Childers, J T; Collins, N J; Curtis, C J; Davis, A O; Eckweiler, S; Eisenhandler, E F; Faulkner, P J W; Fleckner, J; Föhlisch, F; Gee, C N P; Gillman, A R; Goringer, C; Groll, M; Hadley, D R; Hanke, P; Hellman, S; Hidvegi, A; Hillier, S J; Johansen, M; Kluge, E E; Kühl, T; Landon, M; Lendermann, V; Lilley, J N; Mahboubi, K; Mahout, G; Meier, K; Middleton, R P; Moa, T; Morris, J D; Müller, F; Neusiedl, A; Ohm, C; Oltmann, B; Perera, V J O; Prieur, D P F; Qian, W; Rieke, S; Rühr, F; Sankey, D P C; Schäfer, U; Schmitt, K; Schultz-Coulon, H C; Silverstein, S; Sjölin, J; Staley, R J; Stamen, R; Stockton, M C; Tan, C L A; Tapprogge, S; Thomas, J P; Thompson, P D; Watkins, P M; Watson, A; Weber, P; Wessels, M; Wildt, M

2008-01-01

The ATLAS first-level calorimeter trigger is a hardware-based system designed to identify high-pT jets, electron/photon and tau candidates and to measure total and missing ET in the ATLAS calorimeters. The complete trigger system consists of over 300 customdesignedVME modules of varying complexity. These modules are based around FPGAs or ASICs with many configurable parameters, both to initialize the system with correct calibrations and timings and to allow flexibility in the trigger algorithms. The control, testing and monitoring of these modules requires a comprehensive, but well-designed and modular, software framework, which we will describe in this paper.

The ATLAS liquid argon calorimeter--status and expected performance

International Nuclear Information System (INIS)

Schacht, Peter

2004-01-01

For the ATLAS detector at the LHC, the liquid argon technique is exploited for the electromagnetic calorimetry in the central part and for the electromagnetic and hadronic calorimetry in the forward and backward regions. The construction of the calorimeter is well advanced with full cold tests of the barrel calorimeter and first endcap calorimeter only months away. The status of the project is discussed as well as the related results from beam test studies of the various calorimeter subdetectors. The results show that the expected performance meets the ATLAS requirements as specified in the ATLAS Technical Design Report

Multi­-Threaded Algorithms for General purpose Graphics Processor Units in the ATLAS High Level Trigger

CERN Document Server

Conde Mui\\~no, Patricia; The ATLAS collaboration

2016-01-01

General purpose Graphics Processor Units (GPGPU) are being evaluated for possible future inclusion in an upgraded ATLAS High Level Trigger farm. We have developed a demonstrator including GPGPU implementations of Inner Detector and Muon tracking and Calorimeter clustering within the ATLAS software framework. ATLAS is a general purpose particle physics experiment located on the LHC collider at CERN. The ATLAS Trigger system consists of two levels, with level 1 implemented in hardware and the High Level Trigger implemented in software running on a farm of commodity CPU. The High Level Trigger reduces the trigger rate from the 100 kHz level 1 acceptance rate to 1 kHz for recording, requiring an average per­-event processing time of ~250 ms for this task. The selection in the high level trigger is based on reconstructing tracks in the Inner Detector and Muon Spectrometer and clusters of energy deposited in the Calorimeter. Performing this reconstruction within the available farm resources presents a significant ...

CERN Open Days 2013, Point 1 - ATLAS: ATLAS Experiment

CERN Multimedia

CERN Photolab

2013-01-01

Stand description: The ATLAS Experiment at CERN is one of the largest and most complex scientific endeavours ever assembled. The detector, located at collision point 1 of the LHC, is designed to explore the fundamental components of nature and to study the forces that shape our universe. The past year’s discovery of a Higgs boson is one of the most important scientific achievements of our time, yet this is only one of many key goals of ATLAS. During a brief break in their journey, some of the 3000-member ATLAS collaboration will be taking time to share the excitement of this exploration with you. On surface no restricted access  The exhibit at Point 1 will give visitors a chance to meet these modern-day explorers and to learn from them how answers to the most fundamental questions of mankind are being sought. Activities will include a visit to the ATLAS detector, located 80m below ground; watching the prize-winning ATLAS movie in the ATLAS cinema; seeing real particle tracks in a cloud chamber and discussi...

The ATLAS Tile Calorimeter gets into shape!

CERN Multimedia

2002-01-01

The last of the 64 modules for one of the ATLAS Hadron tile calorimeter barrels has just arrived at CERN. This arrival puts an end to two and a half years work assembling and testing all the modules in the Institut de Física d'Altes Energies (IFAE), in Barcelona.

ATLAS recognises its best suppliers

CERN Multimedia

Jenni, P

The ATLAS Collaboration has recently rewarded two of its suppliers in the construction of very major detector components, fabricated in Japan. The ATLAS Supplier Award in recognition of excellent supplier performance was attributed on 2nd September 2002 during a ceremony in Hall 180 to Kawasaki Heavy Industries, while Toshiba Corporation received the award two months before at their headquarters in Japan. The ATLAS experiment will become a reality thanks to a large international collaboration partnership. The industrial suppliers for the components all over the world play a major role in the construction of this gigantic jigsaw for the LHC. And sometimes they perform so well, that their work deserves specially to be recognised. This is the case for Kawasaki Heavy Industries and Toshiba Corporation, producers of the Liquid Argon Barrel Cryostat and of the Superconducting Central Solenoid, respectively. With these awards, the ATLAS Collaboration wants to congratulate Kawasaki and Toshiba for fulfilling the hi...

Tracking and Level-1 triggering in the forward region of the ATLAS Muon Spectrometer at sLHC

International Nuclear Information System (INIS)

Bittner, B; Dubbert, J; Kroha, H; Richter, R; Schwegler, P

2012-01-01

In the endcap region of the ATLAS Muon Spectrometer (η > 1) precision tracking and Level-1 triggering are performed by different types of chambers. Monitored Drift Tube chambers (MDT) and Cathode Strip Chambers (CSC) are used for precision tracking, while Thin Gap Chambers (TGC) form the Level-1 muon trigger, selecting muons with high transverse momentum (p T ). When by 2018 the LHC peak luminosity of 10 34 cm −2 s −1 will be increased by a factor of ∼ 2 and by another factor of ∼ 2–2.5 in about a decade from now (''SLHC''), an improvement of both systems, precision tracking and Level-1 triggering, will become mandatory in order to cope with the high rate of uncorrelated background hits (''cavern background'') and to stay below the maximum trigger rate for the muon system, which is in the range of 10–20 % of the 100 kHz rate, allowed for ATLAS. For the Level-1 trigger of the ATLAS Muon Spectrometer this means a stronger suppression of sub-threshold muons in the high-p T trigger as well as a better rejection of tracks not coming from the primary interaction point. Both requirements, however, can only be fulfilled if spatial resolution and angular pointing accuracy of the trigger chambers, in particular of those in the Inner Station of the endcap, are improved by a large factor. This calls for a complete replacement of the currrently used TGC chambers by a new type of trigger chambers with better performance. In parallel, the precision tracking chambers must be replaced by chambers with higher rate capability to be able to cope with the intense cavern background. In this article we present concepts to decisively improve the Level-1 trigger with newly developed trigger chambers, being characterized by excellent spatial resolution, good time resolution and sufficiently short latency. We also present new types of precision chambers, designed to maintain excellent tracking efficiency and spatial resolution in the presence of high levels of uncorrelated

The CMS Barrel Muon Trigger Upgrade

CERN Document Server

Triossi, Andrea

2017-01-01

ABSTRACT: The increase of luminosity expected by LHC during Phase 1 will impose several constrains for rate reduction while maintaining high efficiency in the CMS Level 1 trigger system. The TwinMux system is the early layer of the muon barrel region that concentrates the information from different subdetectors DT, RPC and HO. It arranges and fan-out the slow optical trigger links from the detector chambers into faster links (10 Gbps) that are sent to the track finders. Results, from collision runs, that confirm the satisfactory operation of the trigger system up to the output of the barrel track finder, will be shown. SUMMARY: In view of the increase of luminosity during phase 1 upgrade of LHC, the muon trigger chain of the Compact Muon Solenoid (CMS) experiment underwent considerable improvements. The muon detector was designed for preserving the complementarity and redundancy of three separate muon detection systems, Cathode Strip Chambers (CSC), Drift Tubes (DT) and Resistive Plate Chambers (RPC), until ...

Cosmic ray runs acquired with ATLAS muon stations

CERN Multimedia

Cerutti, F.

Starting in the fall 2005 several cosmic ray runs have been acquired in the ATLAS pit with six muon stations. These were three large outer and three large middle chambers of the feet sector (sector 13) that have been readout in the ATLAS cavern. In the first data taking period the trigger was based on two large scintillators (~300x30 cm2) positioned in sector 13 just below the large chambers. In this first run the precision chambers (the Monitored Drift Tubes) were operated in a close to final configuration. Typical trigger rates with this setup were of the order of 1 Hz. Several data sets of 10k events were acquired with final electronics up to the muon ROD and analysed with ATHENA-based software. These data allowed the first checks of the functionality and efficiency of the MDT stations in the ATLAS pit and the first measurement of the FE electronics noise in the ATLAS environment. A few event were also collected in a combined run with the TILE barrel calorimeter. An event display of a cosmic ray a...

ATLAS Magnet System Nearing Completion

CERN Document Server

ten Kate, H H J

2008-01-01

The ATLAS Detector at the Large Hadron Collider at CERN is equipped with a superconducting magnet system that consists of a Barrel Toroid, two End-Cap Toroids and a Central Solenoid. The four magnets generate the magnetic field for the muon- and inner tracking detectors, respectively. After 10 years of construction in industry, integration and on-surface tests at CERN, the magnets are now in the underground cavern where they undergo the ultimate test before data taking in the detector can start during the course of next year. The system with outer dimensions of 25 m length and 22 m diameter is based on using conduction cooled aluminum stabilized NbTi conductors operating at 4.6 K and 20.5 kA maximum coil current with peak magnetic fields in the windings of 4.1 T and a system stored magnetic energy of 1.6 GJ. The Barrel Toroid and Central Solenoid were already successfully charged after installation to full current in autumn 2006. This year the system is completed with two End Cap Toroids. The ultimate test of...

Processing of Niobium-Lined M240 Machine Gun Barrels

Science.gov (United States)

2014-11-01

Fig. 5 Finished niobium-lined M240 machine gun barrel with flash suppressor attached ..........11 Fig. 6 End of barrel 1 showing small amount of...the finished barrel is shown in Fig. 5. 11 Fig. 5 Finished niobium-lined M240 machine gun barrel with flash suppressor attached Firing tests

Test and performances of the RPC trigger chambers of the ATLAS experiment at LHC

CERN Document Server

Aielli, G; Ammosov, A; Biglietti, M; Brambilla, Elena; Camarri, P; Canale, V; Caprio, M A; Cardarelli, R; Carlino, G; Cataldi, G; Chiodini, G; Di Simone, A; Di Ciaccio, A; Della Volpe, D; De Asmundis, R; Della Pietra, M; Grancagnolo, F; Gorini, E; Iengo, P; Liberti, B; Patricelli, S; Perrino, R; Primavera, M; Santonico, R; Sehkniadze, G; Spagnolo, S; Sviridov, Yu; Zaetz, V G

2004-01-01

RPCs will be used as trigger detectors in the barrel region of the Muon Spectrometer of the ATLAS experiment at LHC. The total number of RPC units to be installed is 1088, covering a total surface of about 3500m**2. ATLAS RPCs work in avalanche mode with C//2H//2F //4/C//4H //1//0/SF//6 (94.7%/5%/0.3%) gas mixture. A cosmic ray test stand has been designed and built in Naples laboratories in order to carry out a complete test of the ATLAS RPC units. Since August 2002 about 300 units have been tested. A description of the test stand, test procedure and results are presented.

The Development of the Global Feature eXtractor (gFEX) for ATLAS Level 1 Calorimeter Trigger at the LHC

CERN Document Server

Tang, Shaochun; The ATLAS collaboration; Chen, Hucheng

2018-01-01

During the ATLAS Phase-I upgrade, the gFEX will be designed to maintain the trigger acceptance against the increasing luminosity for the ATLAS Level-1 calorimeter trigger system. The gFEX is designed to identify patterns of energy associated with the hadronic decays of high momentum Higgs, W, & Z bosons, top quarks, and exotic particles in real time at the LHC crossing rate. The prototype v1 and v2 have been designed and fully tested in 2015 and 2016 respectively. With the lessons learned, a pre-production board with three UltraScale+ FPGAs and one ZYNQ UltraScale+, and 35 MiniPODs are implemented in an ATCA module. This board will receive coarse-granularity (0.2x0.2) information from the entire ATLAS calorimeters on up to 300 optical fibers and each FPGA has 24 links to the L1Topo at the speed up to 12.8 Gb/s.

Dissection of β-barrel Outer Membrane Protein Assembly Pathways through Characterizing BamA POTRA 1 Mutants of Escherichia coli

Science.gov (United States)

Bennion, Drew; Charlson, Emily S.; Coon, Eric; Misra, Rajeev

2010-01-01

Summary BamA of Escherichia coli is an essential component of the hetero-oligomeric machinery that mediates β-barrel outer membrane protein (OMP) assembly. The C- and N-termini of BamA fold into trans-membrane β-barrel and five soluble POTRA domains, respectively. Detailed characterization of BamA POTRA 1 missense and deletion mutants revealed two competing OMP assembly pathways, one of which is followed by the archetypal trimeric β-barrel OMPs, OmpF and LamB, and is dependent on POTRA 1. Interestingly, our data suggest that BamA also requires its POTRA 1 domain for proper assembly. The second pathway is independent of POTRA 1 and is exemplified by TolC. Site-specific cross-linking analysis revealed that the POTRA 1 domain of BamA interacts with SurA, a periplasmic chaperone required for the assembly of OmpF and LamB, but not that of TolC and BamA. The data suggest that SurA and BamA POTRA 1 domain function in concert to assist folding and assembly of most β-barrel OMPs except for TolC, which folds into a unique soluble α-helical barrel and an OM-anchored β-barrel. The two assembly pathways finally merge at some step beyond POTRA 1 but presumably before membrane insertion, which is thought to be catalyzed by the trans-membrane β-barrel domain of Bam A. PMID:20598079

An important step for the ATLAS toroid magnet

CERN Multimedia

2000-01-01

The ATLAS experiment's prototype toroid coil arrives at CERN from the CEA laboratory in Saclay on 6 October. The world's largest superconducting toroid magnet is under construction for the ATLAS experiment. A nine-metre long fully functional prototype coil was delivered to CERN at the beginning of October and has since been undergoing tests in the West Area. Built mainly by companies in France and Italy under the supervision of engineers from the CEA-Saclay laboratory near Paris and Italy's INFN-LASA, the magnet is a crucial step forward in the construction of the ATLAS superconducting magnet system. Unlike any particle detector that has gone before, the ATLAS detector's magnet system consists of a large toroidal system enclosing a small central solenoid. The barrel part of the toroidal system will use eight toroid coils, each a massive 25 metres in length. These will dwarf the largest toroids in the world when ATLAS was designed, which measure about six metres. So the ATLAS collaboration decided to build a...

The design of a fast Level-1 track trigger for the high luminosity upgrade of ATLAS.

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00413032; The ATLAS collaboration

2016-01-01

The high/luminosity upgrade of the LHC will increase the rate of the proton-proton collisions by approximately a factor of 5 with respect to the initial LHC-design. The ATLAS experiment will upgrade consequently, increasing its robustness and selectivity in the expected high radiation environment. In particular, the earliest, hardware based, ATLAS trigger stage ("Level 1") will require higher rejection power, still maintaining efficient selection on many various physics signatures. The key ingredient is the possibility of extracting tracking information from the brand new full-silicon detector and use it for the process. While fascinating, this solution poses a big challenge in the choice of the architecture, due to the reduced latency available at this trigger level (few tens of micro-seconds) and the high expected working rates (order of MHz). In this paper, we review the design possibilities of such a system in a potential new trigger and readout architecture, and present the performance resulting from a d...

Construction and Tests of Modules for the ATLAS Pixel Detector

CERN Document Server

AUTHOR|(CDS)2068490

2003-01-01

The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system and will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the pixel detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability, all combined with a low material budget. The pre-production phase of such pixel modules has nearly finished, yielding fully functional modules. Results are presented of tests with these modules.

Upgrade of the CMS muon trigger system in the barrel region

CERN Document Server

Rabady, Dinyar; Carlin, Roberto; Codispoti, Giuseppe; Dallavalle, Marco; Erö, Janos; Flouris, Giannis; Foudas, Costas; Fulcher, Jonathan; Guiducci, Luigi; Loukas, Nikitas; Mallios, Stavros; Manthos, Nikos; Papadopoulos, Ioannis; Paradas, Evangelos; Reis, Thomas; Sakulin, Hannes; Sphicas, Paris; Triossi, Andrea; Venturi, Andrea; Wulz, Claudia-Elisabeth

2016-01-01

To maintain the excellent performance of the LHC during its Run-1 also in Run-2, the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade was the re-organisation of the muon trigger path from a subsystem-centric view in which hits in the drift tubes, the cathode strip chambers, and the resistive plate chambers were treated separately in dedicated track-finding systems, to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged already at the track-finding level. This also required the development of a new system to sort as well as cancel-out the muon tracks found by each system. An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF) as well as the cancel-out and sorting layer, the upgraded Global Muon Trigger (µGMT). While the BMTF improves on the proven and well-tested algorithms used in the Drift Tube Track Finder during Run-1, the µGMT i...

Upgrade of the CMS muon trigger system in the barrel region

CERN Document Server

Battilana, Carlo; Codispoti, Giuseppe; Dallavalle, Gaetano-Marco; Ero, Janos; Flouris, Giannis; Fountas, Konstantinos; Fulcher, Jonathan Richard; Guiducci, Luigi; Loukas, Nikitas; Mallios, Stavros; Manthos, Nikolaos; Papadopoulos, Ioannis; Paradas, Evangelos; Rabady, Dinyar Sebastian; Reis, Thomas; Sakulin, Hannes; Sphicas, Paraskevas; Triossi, Andrea; Venturi, Andrea; Wulz, Claudia

2016-01-01

To maintain the excellent performance of the LHC during its Run-1 also in Run-2, the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade was the re-organisation of the muon trigger path from a subsystem-centric view in which hits in the drift tubes, the cathode strip chambers, and the resistive plate chambers were treated separately in dedicated track-finding systems, to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged already at the track-finding level. This also required the development of a new system to sort as well as cancel-out the muon tracks found by each system. An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF) as well as the cancel-out and sorting layer, the upgraded Global Muon Trigger ($\\mu$GMT). While the BMTF improves on the proven and well-tested algorithms used in the Drift Tube Track Finder during Run-1, the $\\m...

Upgrade of the CMS muon trigger system in the barrel region

CERN Document Server

Rabady, Dinyar; Carlin, Roberto; Codispoti, Giuseppe; Dallavalle, Marco; Erö, Janos; Flouris, Giannis; Foudas, Costas; Fulcher, Jonathan; Guiducci, Luigi; Loukas, Nikitas; Mallios, Stavros; Manthos, Nikos; Papadopoulos, Ioannis; Paradas, Evangelos; Reis, Thomas; Sakulin, Hannes; Sphicas, Paris; Triossi, Andrea; Venturi, Andrea; Wulz, Claudia-Elisabeth

2017-01-01

To maintain the excellent performance of the LHC during its Run-1 also in Run-2, the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade was the re-organisation of the muon trigger path from a subsystem-centric view in which hits in the drift tubes, the cathode strip chambers, and the resistive plate chambers were treated separately in dedicated track-finding systems, to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged already at the track-finding level. This also required the development of a new system to sort as well as cancel-out the muon tracks found by each system. An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF) as well as the cancel-out and sorting layer, the upgraded Global Muon Trigger (µGMT). While the BMTF improves on the proven and well-tested algorithms used in the Drift Tube Track Finder during Run-1, the µGMT i...

Study of surface properties of ATLAS12 strip sensors and their radiation resistance

Science.gov (United States)

Mikestikova, M.; Allport, P. P.; Baca, M.; Broughton, J.; Chisholm, A.; Nikolopoulos, K.; Pyatt, S.; Thomas, J. P.; Wilson, J. A.; Kierstead, J.; Kuczewski, P.; Lynn, D.; Hommels, L. B. A.; Ullan, M.; Bloch, I.; Gregor, I. M.; Tackmann, K.; Hauser, M.; Jakobs, K.; Kuehn, S.; Mahboubi, K.; Mori, R.; Parzefall, U.; Clark, A.; Ferrere, D.; Sevilla, S. Gonzalez; Ashby, J.; Blue, A.; Bates, R.; Buttar, C.; Doherty, F.; McMullen, T.; McEwan, F.; O'Shea, V.; Kamada, S.; Yamamura, K.; Ikegami, Y.; Nakamura, K.; Takubo, Y.; Unno, Y.; Takashima, R.; Chilingarov, A.; Fox, H.; Affolder, A. A.; Casse, G.; Dervan, P.; Forshaw, D.; Greenall, A.; Wonsak, S.; Wormald, M.; Cindro, V.; Kramberger, G.; Mandić, I.; Mikuž, M.; Gorelov, I.; Hoeferkamp, M.; Palni, P.; Seidel, S.; Taylor, A.; Toms, K.; Wang, R.; Hessey, N. P.; Valencic, N.; Hanagaki, K.; Dolezal, Z.; Kodys, P.; Bohm, J.; Stastny, J.; Bevan, A.; Beck, G.; Milke, C.; Domingo, M.; Fadeyev, V.; Galloway, Z.; Hibbard-Lubow, D.; Liang, Z.; Sadrozinski, H. F.-W.; Seiden, A.; To, K.; French, R.; Hodgson, P.; Marin-Reyes, H.; Parker, K.; Jinnouchi, O.; Hara, K.; Sato, K.; Hagihara, M.; Iwabuchi, S.; Bernabeu, J.; Civera, J. V.; Garcia, C.; Lacasta, C.; Marti i Garcia, S.; Rodriguez, D.; Santoyo, D.; Solaz, C.; Soldevila, U.

2016-09-01

A radiation hard n+-in-p micro-strip sensor for the use in the Upgrade of the strip tracker of the ATLAS experiment at the High Luminosity Large Hadron Collider (HL-LHC) has been developed by the "ATLAS ITk Strip Sensor collaboration" and produced by Hamamatsu Photonics. Surface properties of different types of end-cap and barrel miniature sensors of the latest sensor design ATLAS12 have been studied before and after irradiation. The tested barrel sensors vary in "punch-through protection" (PTP) structure, and the end-cap sensors, whose stereo-strips differ in fan geometry, in strip pitch and in edge strip ganging options. Sensors have been irradiated with proton fluences of up to 1×1016 neq/cm2, by reactor neutron fluence of 1×1015 neq/cm2 and by gamma rays from 60Co up to dose of 1 MGy. The main goal of the present study is to characterize the leakage current for micro-discharge breakdown voltage estimation, the inter-strip resistance and capacitance, the bias resistance and the effectiveness of PTP structures as a function of bias voltage and fluence. It has been verified that the ATLAS12 sensors have high breakdown voltage well above the operational voltage which implies that different geometries of sensors do not influence their stability. The inter-strip isolation is a strong function of irradiation fluence, however the sensor performance is acceptable in the expected range for HL-LHC. New gated PTP structure exhibits low PTP onset voltage and sharp cut-off of effective resistance even at the highest tested radiation fluence. The inter-strip capacitance complies with the technical specification required before irradiation and no radiation-induced degradation was observed. A summary of ATLAS12 sensors tests is presented including a comparison of results from different irradiation sites. The measured characteristics are compared with the previous prototype of the sensor design, ATLAS07.

Fast shower simulation in the ATLAS calorimeter

CERN Document Server

Barberio, E; Butler, B; Cheung, S L; Dell'Acqua, A; Di Simone, A; Ehrenfeld, W; Gallas, M V; Glazov, A; Marshall, Z; Müller, J; Placakyte, R; Rimoldi, A; Savard, P; Tsulaia, V; Waugh, A; Young, C C

2008-01-01

The time to simulate pp collisions in the ATLAS detector is largely dominated by the showering of electromagnetic particles in the heavy parts of the detector, especially the electromagnetic barrel and endcap calorimeters. Two procedures have been developed to accelerate the processing time of electromagnetic particles in these regions: (1) a fast shower parameterisation and (2) a frozen shower library. Both work by generating the response of the calorimeter to electrons and positrons with Geant 4, and then reintroduce the response into the simulation at runtime.

Increases in the numerical density of GAT-1 positive puncta in the barrel cortex of adult mice after fear conditioning.

Directory of Open Access Journals (Sweden)

Ewa Siucinska

Full Text Available Three days of fear conditioning that combines tactile stimulation of a row of facial vibrissae (conditioned stimulus, CS with a tail shock (unconditioned stimulus, UCS expands the representation of "trained" vibrissae, which can be demonstrated by labeling with 2-deoxyglucose in layer IV of the barrel cortex. We have also shown that functional reorganization of the primary somatosensory cortex (S1 increases GABAergic markers in the hollows of "trained" barrels of the adult mouse. This study investigated how whisker-shock conditioning (CS+UCS affected the expression of puncta of a high-affinity GABA plasma membrane transporter GAT-1 in the barrel cortex of mice 24 h after associative learning paradigm. We found that whisker-shock conditioning (CS+UCS led to increase expression of neuronal and astroglial GAT-1 puncta in the "trained" row compared to controls: Pseudoconditioned, CS-only, UCS-only and Naïve animals. These findings suggest that fear conditioning specifically induces activation of systems regulating cellular levels of the inhibitory neurotransmitter GABA.

Weapons barrel life cycle determination

Directory of Open Access Journals (Sweden)

Nebojša Pene Hristov

2013-10-01

Full Text Available This article describes the dynamic processes within the gun barrel during the firing process in exploitation. It generally defines the basic principles of constructing tube elements, and shows the distortion of the basic geometry of the tube interior due to wear as well as the impact it causes during exploitation. The article also defines basic empirical models as well as a model based on fracture mechanics for the calculation of a use-life of the barrel, and other elements essential for the safe use of the barrel as the basic weapon element. Erosion causes are analysed in order to control and reduce wear and prolong the lifetime of the gun barrel. It gives directions for the reparation of barrels with wasted resources. In conclusion, the most influential elements of tube wear are given as well as possible modifications of existing systems, primarily propellant charges, with a purpose of prolonging lifetime of gun barrels. The guidelines for a proper determination of the lifetime based on the barrel condition assessment are given as well. INTRODUCTION The barrel as the basic element of each weapon is described as well as the processes occurring during the firing that have impulsive character and are accompanied by large amounts of energy. The basic elements of barrel and itheir constructive characteristics are descibed. The relation between Internal ballistics, ie calculation of the propellant gas pressure in the firing process, and structural elements defined by the barrel material resistance is shown. In general, this part of the study explains the methodology of the gun barrel structural elements calculation, ie. barrel geometry, taking into account the degrees of safety in accordance with Military Standards.   TUBE WEAR AND DEFORMATIONS The weapon barrel gradually wears out during exploitation due to which it no longer satisfies the set requirements. It is considered that the barrel has experienced a lifetime when it fails to fulfill the

ATLAS Silicon Microstrip Tracker Operation and Performance

CERN Document Server

Chalupkova, I; The ATLAS collaboration

2012-01-01

The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICS ABCD3TA, working in the binary readout mode. Data is transferred to the off-detector readout electronics via optical fibers. The completed SCT has been installed inside the ATLAS experimental cavern since 2007 and has been operational since then. Calibration data has been taken regularly and analyzed to determine the noise performance of the ...

ATLAS Silicon Microstrip Tracker Operation and Performance

CERN Document Server

NAGAI, K; The ATLAS collaboration

2012-01-01

The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICS ABCD3TA, working in the binary readout mode. Data is transferred to the off-detector readout electronics via optical fibres. The completed SCT has been installed inside the ATLAS experimental cavern since 2007 and has been operational since then. Calibration data has been taken regularly and analysed to determine the noise performance of the ...

ATLAS Silicon Microstrip Tracker Operation and Performance

CERN Document Server

Chalupkova, I; The ATLAS collaboration

2012-01-01

The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector (ID) of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules with a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each side of the barrel). The SCT silicon microstrip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICs ABCD3TA, working in the binary readout mode. Data is transferred to the off-detector readout electronics via optical fibres. SCT has been installed inside the ATLAS experimental cavern since 2007 and has been operational ever since. Calibration data has been taken regularly and analysed to determine the noise performance of the system. ...

The B00 model coil in the ATLAS Magnet Test Facility

CERN Document Server

Dudarev, A; ten Kate, H H J; Anashkin, O P; Keilin, V E; Lysenko, V V

2001-01-01

A 1-m size model coil has been developed to investigate the transport properties of the three aluminum-stabilized superconductors used in the ATLAS magnets. The coil, named B00, is also used for debugging the cryogenic, power and control systems of the ATLAS Magnet Test Facility. The coil comprises two double pancakes made of the barrel toroid and end-cap toroid conductors and a single pancake made of the central solenoid conductor. The pancakes are placed inside an aluminum coil casing. The coil construction and cooling conditions are quite similar to the final design of the ATLAS magnets. The B00 coil is well equipped with various sensors to measure thermal and electrodynamic properties of the conductor inside the coils. Special attention has been paid to the study of the current diffusion process and the normal zone propagation in the ATLAS conductors and windings. Special pick-up coils have been made to measure the diffusion at different currents and magnetic field values. (6 refs).

Supervision of the ATLAS High Level Trigger System

CERN Document Server

Wheeler, S.; Meessen, C.; Qian, Z.; Touchard, F.; Negri, France A.; Zobernig, H.; CHEP 2003 Computing in High Energy Physics; Negri, France A.

2003-01-01

The ATLAS High Level Trigger (HLT) system provides software-based event selection after the initial LVL1 hardware trigger. It is composed of two stages, the LVL2 trigger and the Event Filter. The HLT is implemented as software tasks running on large processor farms. An essential part of the HLT is the supervision system, which is responsible for configuring, coordinating, controlling and monitoring the many hundreds of processes running in the HLT. A prototype implementation of the supervision system, using tools from the ATLAS Online Software system is presented. Results from scalability tests are also presented where the supervision system was shown to be capable of controlling over 1000 HLT processes running on 230 nodes.

Prototype Strip Barrel Modules for the ATLAS ITk Strip Detector

CERN Document Server

Sawyer, Craig; The ATLAS collaboration

2017-01-01

The module design for the Phase II Upgrade of the new ATLAS Inner Tracker (ITk) detector at the LHC employs integrated low mass assembly using single-sided flexible circuits with readout ASICs and a powering circuit incorporating control and monitoring of HV, LV and temperature on the module. Both readout and powering circuits are glued directly onto the silicon sensor surface resulting in a fully integrated, extremely low radiation length module which simultaneously reduces the material requirements of the local support structure by allowing a reduced width stave structure to be employed. Such a module concept has now been fully demonstrated using so-called ABC130 and HCC130 ASICs fabricated in 130nm CMOS technology to readout ATLAS12 n+-in-p silicon strip sensors. Low voltage powering for these demonstrator modules has been realised by utilising a DCDC powerboard based around the CERN FEAST ASIC. This powerboard incorporates an HV multiplexing switch based on a Panasonic GaN transistor. Control and monitori...

Development and application of high-precision metrology for the ATLAS tile-calorimeter construction (pre-assembly experience and lessons)

International Nuclear Information System (INIS)

Batusov, V.Yu.; Budagov, Yu.A.; Khubua, D.I.

2004-01-01

In view of the forthcoming ATLAS assembly in the pit the pre-assembly of the Hadron Tile Calorimeter BARRELS was undertaken at the laboratory hall. A complex of metrology methods (laser, photogrammetry, theodolite, mechanic, PREDICTION programme) developed at the principal stages and resulted in successful high-precision erection of the barrels has been described

The ATLAS/TILECAL Detector Control System

CERN Document Server

Santos, H; The ATLAS collaboration

2010-01-01

Tilecal, the barrel hadronic calorimeter of ATLAS, is a sampling calorimeter where scintillating tiles are embedded in an iron matrix. The tiles are optically coupled to wavelength shifting fibers that carry the optical signal to photo-multipliers. It has a cylindrical shape and is made out of 3 cylinders, the Long Barrel with the LBA and LBC partitions, and the two Extended Barrel with the EBA and EBC partitions. The main task of the Tile calorimeter Detector Control System (DCS) is to enable the coherent and safe operation of the calorimeter. All actions initiated by the operator, as well as all errors, warnings and alarms concerning the hardware of the detector are handled by DCS. The Tile calorimeter DCS controls and monitors mainly the low voltage and high voltage power supply systems, but it is also interfaced with the infrastructure (cooling system and racks), the laser and cesium calibration systems, the data acquisition system, configuration and conditions databases and the detector safety system. In...

Optimisation of the level-1 calorimeter trigger at ATLAS for Run II

Energy Technology Data Exchange (ETDEWEB)

Suchek, Stanislav [Kirchhoff-Institute for Physics, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany); Collaboration: ATLAS-Collaboration

2015-07-01

The Level-1 Calorimeter Trigger (L1Calo) is a central part of the ATLAS Level-1 Trigger system, designed to identify jet, electron, photon, and hadronic tau candidates, and to measure their transverse energies, as well total transverse energy and missing transverse energy. The optimisation of the jet energy resolution is an important part of the L1Calo upgrade for Run II. A Look-Up Table (LUT) is used to translate the electronic signal from each trigger tower to its transverse energy. By optimising the LUT calibration we can achieve better jet energy resolution and better performance of the jet transverse energy triggers, which are vital for many physics analyses. In addition, the improved energy calibration leads to significant improvements of the missing transverse energy resolution. A new Multi-Chip Module (MCM), as a part of the L1Calo upgrade, provides two separate LUTs for jets and electrons/photons/taus, allowing to optimise jet transverse energy and missing transverse energy separately from the electromagnetic objects. The optimisation is validated using jet transverse energy and missing transverse energy triggers turn-on curves and rates.

Qualification Procedures of the CMS Pixel Barrel Modules

CERN Document Server

Starodumov, A; Horisberger, R.; Kastli, H.Chr.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Trueb, P.

2006-01-01

The CMS pixel barrel system will consist of three layers built of about 800 modules. One module contains 66560 readout channels and the full pixel barrel system about 48 million channels. It is mandatory to test each channel for functionality, noise level, trimming mechanism, and bump bonding quality. Different methods to determine the bump bonding yield with electrical measurements have been developed. Measurements of several operational parameters are also included in the qualification procedure. Among them are pixel noise, gains and pedestals. Test and qualification procedures of the pixel barrel modules are described and some results are presented.

Status of the ATLAS Liquid Argon Calorimeter and its performance after one year of LHC operation

CERN Document Server

"Hoffman, J A; The ATLAS collaboration

2011-01-01

The ATLAS experiment is designed to study the proton-proton collisions produced at the LHC with a centre-of-mass energy of 14 TeV. Liquid argon (LAr) sampling calorimeters are used in ATLAS for all electromagnetic calorimetry covering the pseudorapidity region η<3.2, as well as for hadronic calorimetry from η=1.4 to η=4.8. The calorimeter system consists of an electromagnetic barrel calorimeter and two endcaps with electromagnetic (EMEC), hadronic (HEC) and forward (FCAL) calorimeters. The lead-liquid argon sampling technique with an accordion geometry was chosen for the barrel electromagnetic calorimeter (EMB) and adapted to the endcap (EMEC). This geometry allows a uniform acceptance over the whole azimuthal range without any gap. The hadronic endcap calorimeter (HEC) uses a copper-liquid argon sampling technique with plate geometry and is subdivided into two wheels in depth per end-cap. Finally, the forward calorimeter (FCAL) is composed of three modules featuring cylindrical electrodes with thin...

Vinten exposure measurements of the Salem Unit 1 lower core barrel

International Nuclear Information System (INIS)

Glennon, P.T.

1988-01-01

On November 6, 1987, the lower core barrel of Salem Unit I was removed from the reactor vessel and placed in the refueling pool as part of the unit's ten year inspection program. This paper deals with the supporting actions of the dosimetry group of PSE ampersand G. Prior to the move of the lower core barrel, Westinghouse predicted dose rates at one foot in water as a function of axial distance along the core barrel. This prediction was used in planning the health physics requirements associated with the move. It was agreed that a measurement of the axial dose rates would either lend confidence to the predictions or identify weaknesses in them

Upgrade of the CMS muon trigger system in the barrel region

CERN Document Server

AUTHOR|(CDS)2080489; Flouris, Gianis; Fulcher, Jonathan; Loukas, Nikitas; Paradas, Evangelos; Reis,Thomas; Sakulin, Hannes; Wulz, Claudia-Elisabeth

2016-01-01

To maintain the excellent performance shown during the LHCs Run-1 the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade is the re-organization of the muon trigger path from a subsystem-centric view in which hits in the drift tubes (DT), the cathode strip chambers (CSC), and the resistive plate chambers (RPC) were treated separately in dedicated track-finding systems to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged at the track-finding level. This fundamental restructuring of the muon trigger system required the development of a system to receive track candidates from the track-finding layer, remove potential duplicate tracks, and forward the best candidates to the global decision layer.An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF) as well as the cancel-out and sorting layer, the upgraded Global Muon Trigger ($\\mu$GMT). B...

ATLAS Calorimeters: Run-2 performance and Phase-II upgrade

CERN Document Server

Boumediene, Djamel Eddine; The ATLAS collaboration

2017-01-01

The ATLAS detector was designed and built to study proton-proton collisions produced at the LHC at centre-of-mass energies up to 14 TeV and instantaneous luminosities up to 10^{34} cm^{−2} s^{−1}. A liquid argon (LAr)-lead sampling calorimeter is employed as electromagnetic calorimeter and hadronic calorimter, except in the barrel region, where a scintillator-steel sampling calorimeter (TileCal) is used as hadronic calorimter. This presentation will give first an overview of the detector operation and data quality, as well as the achieved performance of the ATLAS calorimetry system. Additionally, the upgrade projects of the ATLAS calorimeter system for the high luminosity phase of the LHC (HL-LHC) will be presented. For the HL-LHC, the instantaneous luminosity is expected to increase up to L ≃ 7.5 × 10^{34} cm^{−2} s^{−1} and the average pile-up up to 200 interactions per bunch crossing. The major R&D item is the upgrade of the electronics for both LAr and Tile calorimeters in order to cope wit...

ATLAS calorimeters: Run-2 performances and Phase-II upgrades

CERN Document Server

Boumediene, Djamel Eddine; The ATLAS collaboration

2017-01-01

The ATLAS detector was designed and built to study proton-proton collisions produced at the LHC at centre-of-mass energies up to 14 TeV and instantaneous luminosities up to $10^{34} cm^{-2} s^{-1}$. A Liquid Argon-lead sampling (LAr) calorimeter is employed as electromagnetic and hadronic calorimeters, except in the barrel region, where a scintillator-steel sampling calorimeter (TileCal) is used as hadronic calorimeter. This presentation gives first an overview of the detector operation and data quality, as well as of the achieved performances of the ATLAS calorimetry system. Additionally the upgrade projects of the ATLAS calorimeter system for the high luminosity phase of the LHC (HL-LHC) are presented. For the HL-LHC, the instantaneous luminosity is expected to increase up to $L \\simeq 7.5 × 10^{34} cm^{-2} s^{-1}$ and the average pile-up up to 200 interactions per bunch crossing. The major R&D item is the upgrade of the electronics for both LAr and Tile calorimeters in order to cope with longer latenc...

Spanish Minister of Science and Technology visits ATLAS

CERN Multimedia

Patrice Loïez

2002-01-01

H.E. Mr Josep Piqué i Camps, Minister for Science and Technology, Spain, came to CERN in November. He is seen here visiting the ATLAS assembly hall. Photo 01: The Minister (left) is greeted by Peter Jenni, spokesperson for the ATLAS collaboration. In the centre is Matteo Cavalli-Sforza, Spanish scientist at CERN. Photo 02: The Minister (left) in discussion with Peter Jenni. Photo 03: Peter Jenni shows the visitors one of eight vacuum vessels being built by Spanish company Felguera Construcciones Mecanicas SA for the superconducting coils of the air-core ATLAS barrel toroid magnet system: (left to right) Matteo Cavalli-Sforza of CERN; the Minister; M. Aguilar-Benitez, Spanish delegate to CERN Council; G. Léon; and Peter Jenni.

ATLAS cavern hand-over ceremony on 4th June 2003 in the presence of the President of the Swiss Confederation

CERN Multimedia

Jenni, P

The 4th of June 2003 will be remembered as a very major milestone in the history of the ATLAS detector construction. In the presence of the President of the Swiss Confederation, Mr. Pascal Couchepin, the ATLAS cavern was handed over by the CERN Director-General, Professor Luciano Maiani, to the Collaboration. For this highly press-mediated event the CERN Director-General had invited some 100 political personalities and representatives from the Geneva and the neighbouring French regions, and from CERN Member and Non-Member States. The surface building was transformed for this occasion into an attractive multi- media hall with films and exhibitions from ATLAS and the civil engineering, with a bar and the CERN jazz band. Besides of course the cavern itself, the Swiss President visited also the ATLAS barrel toroid magnet and the LAr calorimeter assembly activities in Hall 180. The Swiss President visiting the Barrel Toroid integration work in Hall 180 He was very interested and impressed by these, aski...

Test Results of a 1.2 kg/s Centrifugal Liquid Helium Pump for the ATLAS Superconducting Toroid Magnet System

CERN Document Server

Pengo, R; Passardi, Giorgio; Pirotte, O; ten Kate, H H J

2002-01-01

The toroid superconducting magnet of ATLAS-LHC experiment at CERN will be indirectly cooled by means of forced flow of liquid helium at about 4.5 K. A centrifugal pump will be used, providing a mass flow of 1.2 kg/s and a differential pressure of 40 kPa (ca. 400 mbar) at about 4300 rpm. Two pumps are foreseen, one for redundancy, in order to feed in parallel the cooling circuits of the Barrel and the two End-Caps toroid magnets. The paper describes the tests carried out at CERN to measure the characteristic curves, i.e. the head versus the mass flow at different rotational speeds, as well as the pump total efficiency. The pump is of the "fullemission" type, i.e. with curved blades and it is equipped with an exchangeable inducer. A dedicated pump test facility has been constructed at CERN, which includes a Coriolis-type liquid helium mass flow meter. This facility is connected to the helium refrigerator used for the tests at CERN of the racetrack magnets of the Barrel and of the End-Cap toroids.

Staves and Petals: Multi-module Local Support Structures of the ATLAS ITk Strips Upgrade

CERN Document Server

Garcia-Argos, Carlos; The ATLAS collaboration

2017-01-01

The ATLAS Inner Tracker (ITk) is an all-silicon tracker that will replace the existing inner detector at the Phase-II Upgrade of ATLAS. The outermost part of the tracker consists of the strips tracker, in which the sensors elements consist of silicon micro-strip sensors with strip lengths varying from 1.7 to up to 10 cm. The current design, at the moment under internal review in the Strips part of the Technical Design Report (TDR), envisions a four-layer barrel and two six-disk endcap regions. The sensor and readout units (“modules”) are directly glued onto multi-module, low-mass, high thermal performance carbon fiber structures, called “staves” for the barrel and “petals” for the endcap. They provide cooling, power, data and control lines to the modules with a minimal amount of external services. An extensive prototyping program was put in place over the last years to fully characterize these structures mechanically, thermally, and electrically. Thermo-mechanical stave and petal prototypes have r...

Development of the detector control system for the ATLAS Level-1 trigger and measurement of the single top production cross section

CERN Document Server

Curtis, Christopher J

This thesis discusses the development of the Detector Control System (DCS) for the ATLAS Level-1 Trigger. Microcontroller code has been developed to read out slow controls data from the Level-1 Calorimeter Trigger modules into the wider DCS. Back-end software has been developed for archiving this data. A Finite State Machine (FSM) has also been developed to offer remote access to the L1 Trigger hardware from the ATLAS Control Room. This Thesis also discusses the discovery potential for electroweak single top production during early running. Using Monte Carlo data some of the major systematics are discussed. A potential upper limit on the production cross section is calculated to be 45.2 pb. If the Standard Model prediction is assumed, a measured signal could potentially have a significance of up to 2.23¾ using 200 pb−1 of data.

The ATLAS online High Level Trigger framework experience reusing offline software components in the ATLAS trigger

CERN Document Server

Wiedenmann, W

2009-01-01

Event selection in the Atlas High Level Trigger is accomplished to a large extent by reusing software components and event selection algorithms developed and tested in an offline environment. Many of these offline software modules are not specifically designed to run in a heavily multi-threaded online data flow environment. The Atlas High Level Trigger (HLT) framework based on the Gaudi and Atlas Athena frameworks, forms the interface layer, which allows the execution of the HLT selection and monitoring code within the online run control and data flow software. While such an approach provides a unified environment for trigger event selection across all of Atlas, it also poses strict requirements on the reused software components in terms of performance, memory usage and stability. Experience of running the HLT selection software in the different environments and especially on large multi-node trigger farms has been gained in several commissioning periods using preloaded Monte Carlo events, in data taking peri...

ATLAS RPC Quality Assurance results at INFN Lecce

CERN Document Server

INSPIRE-00211509; Borjanovic, I.; Cataldi, G.; Cazzato, A.; Chiodini, G.; Coluccia, M. R.; Creti, P.; Gorini, E.; Grancagnolo, F.; Perrino, R.; Primavera, M.; Spagnolo, S.; Tassielli, G.; Ventura, A.

2006-01-01

The main results of the quality assurance tests performed on the Resistive Plate Chamber used by the ATLAS experiment at LHC as muon trigger chambers are reported and discussed. Since July 2004, about 270 RPC units has been certified at INFN Lecce site and delivered to CERN, for being integrated in the final muon station of the ATLAS barrel region. We show the key RPC characteristics which qualify the performance of this detector technology as muon trigger chamber in the harsh LHC enviroments. These are dark current, chamber efficiency, noise rate, gas volume tomography, and gas leakage.

Studies of the ATLAS Inner Detector material using $\\sqrt{s}=$13 TeV $pp$ collision data

CERN Document Server

The ATLAS collaboration

2015-01-01

The ATLAS Inner Detector comprises three different technologies: the Pixel detector (Pixel), the silicon strip tracker (SCT), and the transition radiation drift tube tracker (TRT). The material in the ATLAS Inner Detector is studied with several methods, using the $pp$ collision sample collected at $\\sqrt{s}=$13 TeV in 2015. The material within the innermost barrel regions of the ATLAS Inner Detector is studied using reconstructed hadronic interaction and photon conversion vertices from samples of minimum bias events. It was found that the description of the Insertable B-Layer, which is the new, innermost Pixel layer installed in 2014, in the geometry model was missing some material components. After updating the model, data and simulation show good agreement at the barrel region. The Pixel services (cables, cooling pipes, support trays) were modified between the Pixel and SCT detectors in 2014. The material in this region is also studied by investigating the efficiency with which tracks reconstructed only in...

ATLAS Level-1 Calorimeter Trigger Subsystem Tests of a Prototype Cluster Processor Module

CERN Document Server

Garvey, J; Apostologlou, P; Ay, C; Barnett, B M; Bauss, B; Brawn, I P; Bohm, C; Dahlhoff, A; Davis, A O; Edwards, J; Eisenhandler, E F; Gee, C N P; Gillman, A R; Hanke, P; Hellman, S; Hidévgi, A; Hillier, S J; Jakobs, K; Kluge, E E; Landon, M; Mahboubi, K; Mahout, G; Meier, K; Meshkov, P; Moye, T H; Mills, D; Moyse, E; Nix, O; Penno, K; Perera, V J O; Qian, W; Schmitt, K; Schäfer, U; Silverstein, S; Staley, R J; Thomas, J; Trefzger, T M; Watkins, P M; Watson, A; 9th Workshop On Electronics For LHC Experiments - LECC 2003

2003-01-01

The Level-1 Calorimeter Trigger consists of a Preprocessor (PP), a Cluster Processor (CP), and a Jet/Energy-sum Processor (JEP). The CP and JEP receive digitised trigger-tower data from the Preprocessor and produce trigger multiplicity and Region-of-Interest (RoI) information. The trigger will also provide intermediate results to the data acquisition (DAQ) system for monitoring and diagnostic purposes by using Readout Driver (ROD) Modules. The CP Modules (CPM) are designed to find isolated electron/photon and hadron/tau clusters in overlapping windows of trigger towers. Each pipelined CPM processes 8-bit data from a total of 128 trigger towers at each LHC crossing. Four full-specification prototypes of CPMs have been built and results of complete tests on individual boards will be presented. These modules were then integrated with other modules to build an ATLAS Level-1 Calorimeter Trigger subsystem test bench. Realtime data were exchanged between modules, and time-slice readout data were tagged and transferr...

Two ATLAS trackers become one

CERN Multimedia

2006-01-01

The ATLAS inner detector barrel comes one step closer to completion as the semiconductor tracker is merged with the transition radiation tracker. ATLAS collaborators prepare for the insertion of the semiconductor tracker (SCT, behind) into the transition radiation tracker (TRT, in front). Some had hoped it would fall on Valentine's Day. But despite the slight delay, Friday 17 February was lovingly embraced as 'Conception Day,' when dozens of physicists and engineers from the international collaboration gathered to witness the insertion of the ATLAS semiconductor tracker into the transition radiation tracker, a major milestone in the assembly of the experiment's inner detector. With just millimeters of room for error, the cylindrical trackers were slid into each other as inner detector integration coordinator Heinz Pernegger issued commands and scientists held out flashlights, lay on their backs and stood on ladders to take careful measurements. Each tracker is the result of about 10 years of international ...

Globally intertwined evolutionary history of giant barrel sponges

Science.gov (United States)

Swierts, Thomas; Peijnenburg, Katja T. C. A.; de Leeuw, Christiaan A.; Breeuwer, Johannes A. J.; Cleary, Daniel F. R.; de Voogd, Nicole J.

2017-09-01

Three species of giant barrel sponge are currently recognized in two distinct geographic regions, the tropical Atlantic and the Indo-Pacific. In this study, we used molecular techniques to study populations of giant barrel sponges across the globe and assessed whether the genetic structure of these populations agreed with current taxonomic consensus or, in contrast, whether there was evidence of cryptic species. Using molecular data, we assessed whether giant barrel sponges in each oceanic realm represented separate monophyletic lineages. Giant barrel sponges from 17 coral reef systems across the globe were sequenced for mitochondrial (partial CO1 and ATP6 genes) and nuclear (ATPsβ intron) DNA markers. In total, we obtained 395 combined sequences of the mitochondrial CO1 and ATP6 markers, which resulted in 17 different haplotypes. We compared a phylogenetic tree constructed from 285 alleles of the nuclear intron ATPsβ to the 17 mitochondrial haplotypes. Congruent patterns between mitochondrial and nuclear gene trees of giant barrel sponges provided evidence for the existence of multiple reproductively isolated species, particularly where they occurred in sympatry. The species complexes in the tropical Atlantic and the Indo-Pacific, however, do not form separate monophyletic lineages. This rules out the scenario that one species of giant barrel sponge developed into separate species complexes following geographic separation and instead suggests that multiple species of giant barrel sponges already existed prior to the physical separation of the Indo-Pacific and tropical Atlantic.

Construction and tests of the Atlas barrel pre sampler and study of the photon/pion rejection in the electromagnetic calorimeter; Realisation du pre-echantillonneur central d'ATLAS et etude de la separation {gamma}/{pi}{sup 0} dans le calorimetre electromagnetique

Energy Technology Data Exchange (ETDEWEB)

Saboumazrag, S

2004-02-01

ATLAS is one of the detectors which will equip the future proton-proton collider LHC at CERN. The main motivation for the ATLAS experiment is the quest for the Higgs boson. The observation of this particle would be an important step in the understanding of particle physics in the context of the standard model, with or without supersymmetry. This thesis aims to present the construction of the barrel pre-sampler which will equip the front face of the ATLAS electromagnetic calorimeter. The construction and tests of sectors were achieved at the Laboratory of Subatomic Physics and Cosmology of Grenoble. Two of these sectors were mounted on one module of the electromagnetic calorimeter and tested with electron, photon and muon beams at CERN. I participated in these tests and analysed the data. The results were compared to a Monte-Carlo simulation GEANT3. One of the difficulties lies in the necessity to discard photons coming from {pi}{sup 0} {yields} {gamma}{gamma} events because they can be mistaken for photons released in gamma channels of Higgs boson decay. In the mass range spreading from 95 MeV to 150 MeV, H{sup 0} {yields} {gamma}{gamma} is the most adequate process to detect the Higgs boson. A study of the discard parameter {gamma}/{pi}{sup 0} has been performed. For a photon detection efficiency of 90%, the average discard parameter has been assessed to be 2.5 which is slightly lower than the value given by the simulation.

A crystal barrel

CERN Multimedia

2007-01-01

The production of crystals for the barrel of the CMS electromagnetic calorimeter has been completed. This is an important milestone for the experiment, which received the last of its 62,960 crystals on 9 March. The members of the team responsible for the crystal acceptance testing at CERN display the last crystal for the CMS electromagnetic calorimeter barrel. From left to right: Igor Tarasov, Etiennette Auffray and Hervé Cornet.One of the six machines specially developed to measure 67 different parameters on each crystal. Igor Tarasov is seen inserting the last batch of crystals into the machine. The last of the 62,960 CMS barrel crystals arrived at CERN on 9 March. Once removed from its polystyrene protection, this delicate crystal, like thousands of its predecessors, will be inserted into the last of the 36 supermodules of the barrel electromagnetic calorimeter in a few days' time. This marks the end of an important chapter in an almost 15-year-long journey by the CMS crystals team, some of whose member...

Fluorocarbon evaporative cooling developments for the ATLAS pixel and semiconductor tracking detectors

CERN Document Server

Anderssen, E; Berry, S; Bonneau, P; Bosteels, Michel; Bouvier, P; Cragg, D; English, R; Godlewski, J; Górski, B; Grohmann, S; Hallewell, G D; Hayler, T; Ilie, S; Jones, T; Kadlec, J; Lindsay, S; Miller, W; Niinikoski, T O; Olcese, M; Olszowska, J; Payne, B; Pilling, A; Perrin, E; Sandaker, H; Seytre, J F; Thadome, J; Vacek, V

1999-01-01

Heat transfer coefficients 2-5.103 Wm-2K-1 have been measured in a 3.6 mm I.D. heated tube dissipating 100 Watts - close to the full equivalent power (~110 W) of a barrel SCT detector "stave" - over a range of power dissipations and mass flows in the above fluids. Aspects of full-scale evaporative cooling circulator design for the ATLAS experiment are discussed, together with plans for future development.

Simulation of dynamic pile-up corrections in the ATLAS level-1 calorimeter trigger

Energy Technology Data Exchange (ETDEWEB)

Narrias-Villar, Daniel; Wessels, Martin; Brandt, Oleg [Heidelberg University, Heidelberg (Germany)

2015-07-01

The Level-1 Calorimeter Trigger is a crucial part of the ATLAS trigger effort to select only relevant physics events out of the large number of interactions at the LHC. In Run II, in which the LHC will double the centre-of-mass energy and further increase the instantaneous luminosity, pile-up is a limiting key factor for triggering and reconstruction of relevant events. The upgraded L1Calo Multi-Chip-Modules (nMCM) will address this problem by applying dynamic pile-up corrections in real-time, of which a precise simulation is crucial for physics analysis. Therefore pile-up effects are studied in order to provide a predictable parametrised baseline correction for the Monte Carlo simulation. Physics validation plots, such as trigger rates and turn-on curves are laid out.

A self seeded first level track trigger for ATLAS

International Nuclear Information System (INIS)

Schöning, A

2012-01-01

For the planned high luminosity upgrade of the Large Hadron Collider, aiming to increase the instantaneous luminosity to 5 × 10 34 cm −2 s −1 , the implementation of a first level track trigger has been proposed. This trigger could be installed in the year ∼ 2021 along with the complete renewal of the ATLAS inner detector. The fast readout of the hit information from the Inner Detector is considered as the main challenge of such a track trigger. Different concepts for the implementation of a first level trigger are currently studied within the ATLAS collaboration. The so called 'Self Seeded' track trigger concept exploits fast frontend filtering algorithms based on cluster size reconstruction and fast vector tracking to select hits associated to high momentum tracks. Simulation studies have been performed and results on efficiencies, purities and trigger rates are presented for different layouts.

Fast Dump of the ATLAS Toroids

CERN Document Server

Dudarev, A; Volpini, Giovanni; Dudarev, Alexey; Kate, Herman Ten

2010-01-01

The toroidal magnet system of the ATLAS Detector at CERN consists of a Barrel Toroid (BT) and two End Cap Toroids (ECT-A and ECT-C). Each toroid is built up from eight racetrack coils wound with an aluminum stabilized NbTi conductor and indirectly cooled by forced flow liquid helium. The three toroids operate in series at 20.5 kA with a total stored energy of 1.5 GJ. In order to verify the reliability and effectiveness of the quench protection system, series of fast dump tests have been performed first of the single toroids and finally of the entire toroidal magnet system. In this paper a model to simulate the fast dump of the ATLAS toroids in single mode operation and in full system configuration is presented. The model is validated through comparison with measured data extracted from the ramp-and-quench runs. The calculated energy dissipation in the various coils is in very good agreement (within 1-2\\%) with the enthalpy changes estimated from the temperature measurements of the different parts of the cold ...

Streamlined Calibration of the ATLAS Muon Spectrometer Precision Chambers

CERN Document Server

Levin, DS; The ATLAS collaboration; Dai, T; Diehl, EB; Ferretti, C; Hindes, JM; Zhou, B

2009-01-01

The ATLAS Muon Spectrometer is comprised of nearly 1200 optically Monitored Drifttube Chambers (MDTs) containing 354,000 aluminum drift tubes. The chambers are configured in barrel and endcap regions. The momentum resolution required for the LHC physics reach (dp/p = 3% and 10% at 100 GeV and 1 TeV) demands rigorous MDT drift tube calibration with frequent updates. These calibrations (RT functions) convert the measured drift times to drift radii and are a critical component to the spectrometer performance. They are sensitive to the MDT gas composition: Ar 93%, CO2 7% at 3 bar, flowing through the detector at arate of 100,000 l hr−1. We report on the generation and application of Universal RT calibrations derived from an inline gas system monitor chamber. Results from ATLAS cosmic ray commissioning data are included. These Universal RTs are intended for muon track reconstuction in LHC startup phase.

The Virtual Point 1 event display for the ATLAS experiment

International Nuclear Information System (INIS)

Kittelmann, Thomas; Tsulaia, Vakhtang; Boudreau, Joseph; Moyse, Edward

2010-01-01

We present an event display for the ATLAS Experiment, called Virtual Point 1 (VP1), designed initially for deployment at point 1 of the LHC, the location of the ATLAS detector. The Qt/OpenGL based application provides truthful and interactive 3D representations of both event and non-event data, and now serves a general-purpose role within the experiment. Thus, VP1 is used both online (in the control room itself or remotely via a special 'live' mode) and offline environments to provide fast debugging and understanding of events, detector status and software. In addition to a flexible plugin infrastructure and a high level of configurability, this multi-purpose role is mainly facilitated by embedding the application directly into the ATLAS offline software framework, enabling it to use the native Event Data Model directly, and thus run on any source of ATLAS data, or even directly from within processes such as reconstruction jobs. Finally, VP1 provides high-quality pictures and movies, useful for outreach purposes.

The ATLAS Data Acquisition and High Level Trigger system

International Nuclear Information System (INIS)

2016-01-01

This paper describes the data acquisition and high level trigger system of the ATLAS experiment at the Large Hadron Collider at CERN, as deployed during Run 1. Data flow as well as control, configuration and monitoring aspects are addressed. An overview of the functionality of the system and of its performance is presented and design choices are discussed.

The ATLAS trigger high-level trigger commissioning and operation during early data taking

CERN Document Server

Goncalo, R

2008-01-01

The ATLAS experiment is one of the two general-purpose experiments due to start operation soon at the Large Hadron Collider (LHC). The LHC will collide protons at a centre of mass energy of 14~TeV, with a bunch-crossing rate of 40~MHz. The ATLAS three-level trigger will reduce this input rate to match the foreseen offline storage capability of 100-200~Hz. After the Level 1 trigger, which is implemented in custom hardware, the High-Level Trigger (HLT) further reduces the rate from up to 100~kHz to the offline storage rate while retaining the most interesting physics. The HLT is implemented in software running in commercially available computer farms and consists of Level 2 and Event Filter. To reduce the network data traffic and the processing time to manageable levels, the HLT uses seeded, step-wise reconstruction, aiming at the earliest possible rejection. Data produced during LHC commissioning will be vital for calibrating and aligning sub-detectors, as well as for testing the ATLAS trigger and setting up t...

Correcting the Chromatic Aberration in Barrel Distortion of Endoscopic Images

Directory of Open Access Journals (Sweden)

Y. M. Harry Ng

2003-04-01

Full Text Available Modern endoscopes offer physicians a wide-angle field of view (FOV for minimally invasive therapies. However, the high level of barrel distortion may prevent accurate perception of image. Fortunately, this kind of distortion may be corrected by digital image processing. In this paper we investigate the chromatic aberrations in the barrel distortion of endoscopic images. In the past, chromatic aberration in endoscopes is corrected by achromatic lenses or active lens control. In contrast, we take a computational approach by modifying the concept of image warping and the existing barrel distortion correction algorithm to tackle the chromatic aberration problem. In addition, an error function for the determination of the level of centroid coincidence is proposed. Simulation and experimental results confirm the effectiveness of our method.

Operation and Performance of the ATLAS Level-1 Calorimeter and Topological Triggers in Run 2

CERN Document Server

Weber, Sebastian Mario; The ATLAS collaboration

2017-01-01

In Run 2 at CERN's Large Hadron Collider, the ATLAS detector uses a two-level trigger system to reduce the event rate from the nominal collision rate of 40 MHz to the event storage rate of 1 kHz, while preserving interesting physics events. The first step of the trigger system, Level-1, reduces the event rate to 100 kHz within a latency of less than $2.5$ $\\mu\\text{s}$. One component of this system is the Level-1 Calorimeter Trigger (L1Calo), which uses coarse-granularity information from the electromagnetic and hadronic calorimeters to identify regions of interest corresponding to electrons, photons, taus, jets, and large amounts of transverse energy and missing transverse energy. In these proceedings, we discuss improved features and performance of the L1Calo system in the challenging, high-luminosity conditions provided by the LHC in Run 2. A new dynamic pedestal correction algorithm reduces pile-up effects and the use of variable thresholds and isolation criteria for electromagnetic objects allows for opt...

Recent test results on the ATLAS SCT detector

International Nuclear Information System (INIS)

Pernegger, H.

2003-01-01

The ATLAS Semiconductor Tracker (SCT) will be a central part of the tracking system of the ATLAS experiment. The SCT, which is currently under construction, will consist of four concentric barrels of silicon detectors as well as two silicon endcap detectors formed by nine disks each. After an overview of the SCT and the detector module layout, the paper will summarize recent test results obtained from silicon detector modules, which have been extensively tested before starting their large series production. The tests presented here cover electrical performance of individual modules, their performance after irradiation, as well as system tests in a multi-module setup

The ATLAS online High Level Trigger framework: Experience reusing offline software components in the ATLAS trigger

International Nuclear Information System (INIS)

Wiedenmann, Werner

2010-01-01

Event selection in the ATLAS High Level Trigger is accomplished to a large extent by reusing software components and event selection algorithms developed and tested in an offline environment. Many of these offline software modules are not specifically designed to run in a heavily multi-threaded online data flow environment. The ATLAS High Level Trigger (HLT) framework based on the GAUDI and ATLAS ATHENA frameworks, forms the interface layer, which allows the execution of the HLT selection and monitoring code within the online run control and data flow software. While such an approach provides a unified environment for trigger event selection across all of ATLAS, it also poses strict requirements on the reused software components in terms of performance, memory usage and stability. Experience of running the HLT selection software in the different environments and especially on large multi-node trigger farms has been gained in several commissioning periods using preloaded Monte Carlo events, in data taking periods with cosmic events and in a short period with proton beams from LHC. The contribution discusses the architectural aspects of the HLT framework, its performance and its software environment within the ATLAS computing, trigger and data flow projects. Emphasis is also put on the architectural implications for the software by the use of multi-core processors in the computing farms and the experiences gained with multi-threading and multi-process technologies.

Diagnostic Systems and Resources utilization of the ATLAS High Level Trigger

CERN Document Server

Sidoti, A; The ATLAS collaboration; Ospanov, R

2010-01-01

Since the LHC started colliding protons in December 2009, the ATLAS trigger has operated very successfully with a collision rate which has increased by several orders of magnitude. The trigger monitoring and data quality infrastructure was essential to this success. We describe the software tools used to monitor the trigger system performance and assess the overall quality of the trigger selection during collisions running. ATLAS has broad physics goals which require a large number of different active triggers due to complex event topology, requiring quite sophisticated software structures and concepts. The trigger of the ATLAS experiment is built as a three level system. The first level is realized in hardware while the high level triggers (HLT) are software based and run on large PC farms. The trigger reduces the bunch crossing rate of 40 MHz, at design, to an average event rate of about 200 Hz for storage. Since the ATLAS detector is a general purpose detector, the trigger must be sensitive to a large numb...

Assembly and Electrical Tests of the First Full-size Forward Module for the ATLAS ITk Strip Detector

CERN Document Server

Garcia-Argos, Carlos; The ATLAS collaboration

2018-01-01

The ATLAS experiment will replace the existing Inner Detector by an all-silicon detector named the Inner Tracker (ITk) for the High Luminosity LHC upgrades. In the outer region of the Inner Tracker is the strip detector, which consists of a four layer barrel and six discs to each side of the barrel, with silicon-strip modules as basic units. Each module is composed of a sensor and one or more flex circuits that hold the read-out electronics. In the experiment, the modules are mounted on support structures with integrated power and cooling. The modules are designed with geometries that accommodate the central and forward regions, with rectangular sensors in the barrels and wedge shaped sensors in the end-caps. The strips lengths and pitch sizes vary according to the occupancy of the region. In this contribution, we present the construction and results of the electrical tests of the first full-size module of the innermost forward region, named \\textit{Ring 0} in the ATLAS ITk strip detector nomenclature. This m...

Assembly and Electrical Tests of the First Full-size Forward Module for the ATLAS ITk Strip Detector

CERN Document Server

Garcia-Argos, Carlos; The ATLAS collaboration

2017-01-01

The ATLAS experiment will replace the existing Inner Detector by an all-silicon detector named the Inner Tracker (ITk) for the High Luminosity LHC upgrades. In the outer region of the Inner Tracker is the strip detector, which consists of a four layer barrel and six discs to each side of the barrel, with silicon-strip modules as basic units. Each module is composed of a sensor and one or more flex circuits that hold the read-out electronics. In the experiment, the modules are mounted on support structures with integrated power and cooling. The modules are designed with geometries that accommodate the central and forward regions, with rectangular sensors in the barrels and wedge shaped sensors in the end-caps. The strips lengths and pitch sizes vary according to the occupancy of the region. In this contribution, we present the construction and the results of the electrical tests of the first full-size module of the innermost forward region, named Ring 0 in the ATLAS ITk strip detector nomenclature. This module...

Sodium Dichromate Barrel Landfill expedited response action proposal

International Nuclear Information System (INIS)

1993-09-01

The US Environmental Protection Agency (EPA) and Washington State Department of Ecology (Ecology) recommended that the US Department of Energy (DOE) prepare an expedited response action (ERA) for the Sodium Dichromate Barrel Landfill. The Sodium Dichromate Barrel Disposal Site was used in 1945 for disposal of crushed barrels. The site location is the sole waste site within the 100-IU-4 Operable Unit. The Waste Information Data System (WIDS 1992) assumes that the crushed barrels contained 1% residual sodium dichromate at burial time and that only buried crushed barrels are at the site. Burial depth is shallow since visual inspection finds numerous barrel debris on the surface. A non-time-critical ERA proposal includes preparation of an engineering evaluation and cost analysis (EE/CA) section. The EE/CA is a rapid, focused evaluation of available technologies using specific screening factors to assess feasibility, appropriateness, and cost. The ERA goal is to reduce the potential for any contaminant migration from the landfill to the soil column, groundwater, and Columbia River. Since the landfill is the only waste site within the operable unit, the ERA will present a final remediation of the 100-IU-4 operable unit

ATLAS with six of its torodial coils

CERN Document Server

Maximilien Brice

2005-01-01

The ATLAS experiment at the LHC at CERN has received six of its eight torodial magnets in this photo taken in mid-July 2005. These torodial magnets will generate the magnetic field within the detector causing charged particles to follow curved paths that will allow their momentum to be measured. Also the barrel hadronic calorimeter can be seen in the background, which recorded its first cosmic ray hits in early July.

Studies of ATM for ATLAS high-level triggers

CERN Document Server

Bystrický, J; Huet, M; Le Dû, P; Mandjavidze, I D

2001-01-01

This paper presents some of the conclusions of our studies on asynchronous transfer mode (ATM) and fast Ethernet in the ATLAS level-2 trigger pilot project. We describe the general concept and principles of our data-collection and event-building scheme that could be transposed to various experiments in high-energy and nuclear physics. To validate the approach in view of ATLAS high-level triggers, we assembled a testbed composed of up to 48 computers linked by a 7.5-Gbit/s ATM switch. This modular switch is used as a single entity or is split into several smaller interconnected switches. This allows study of how to construct a large network from smaller units. Alternatively, the ATM network can be replaced by fast Ethernet. We detail the operation of the system and present series of performance measurements made with event-building traffic pattern. We extrapolate these results to show how today's commercial networking components could be used to build a 1000-port network adequate for ATLAS needs. Lastly, we li...

Vertex measurement at a hadron collider. The ATLAS pixel detector

International Nuclear Information System (INIS)

Grosse-Knetter, J.

2008-03-01

The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system and will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the Pixel Detector near the interaction point requires excellent radiation hardness, fast read-out, mechanical and thermal robustness, good long-term stability, all combined with a low material budget. The new design concepts used to meet the challenging requirements are discussed with their realisation in the Pixel Detector, followed by a description of a refined and extensive set of measurements to assess the detector performance during and after its construction. (orig.)

Instrumentation of a Level-1 Track Trigger in the ATLAS detector for the High Luminosity LHC

CERN Document Server

Boisvert, V; The ATLAS collaboration

2012-01-01

The Large Hadron Collider will be upgraded in order to reach an instantaneous luminosity of $L=5 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$. A challenge for the detectors will be to cope with the excessive rate of events coming into the trigger system. In order to maintain the capability of triggering on single lepton objects with momentum thresholds of $p_T 25$ GeV, the ATLAS detector is planning to use tracking information at the Level-1 (hardware) stage of the trigger system. Two options are currently being studied: a L0/L1 trigger design using a double buffer front-end architecture and a single hardware trigger level which uses trigger layers in the new tracker system. Both options are presented as well as results from simulation studies.

Upgrade of the CMS muon trigger system in the barrel region

International Nuclear Information System (INIS)

Rabady, Dinyar; Ero, Janos; Flouris, Giannis; Fulcher, Jonathan; Loukas, Nikitas; Paradas, Evangelos; Reis, Thomas; Sakulin, Hannes; Wulz, Claudia-Elisabeth

2017-01-01

To maintain the excellent performance shown during the LHC's Run-1 the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade is the re-organization of the muon trigger path from a subsystem-centric view in which hits in the drift tubes (DT), the cathode strip chambers (CSC), and the resistive plate chambers (RPC) were treated separately in dedicated track-finding systems to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged at the track-finding level. This fundamental restructuring of the muon trigger system required the development of a system to receive track candidates from the track-finding layer, remove potential duplicate tracks, and forward the best candidates to the global decision layer. An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF), as well as the cancel-out and sorting layer: the upgraded Global Muon Trigger (μGMT). Both the BMTF and μGMT have been implemented in a Xilinx Virtex-7 card utilizing the microTCA architecture. While the BMTF improves on the proven and well-tested algorithms used in the Drift Tube Track Finder during Run-1, the μGMT is an almost complete re-development due to the re-organization of the underlying systems from track-finders for a specific detector to regional track finders covering a given area of the whole detector. Additionally the μGMT calculates a muon's isolation using energy information received from the calorimeter trigger. This information is added to the muon objects forwarded to the global decision layer, the so-called Global Trigger. - Highlights: • Presented upgraded Global Muon Trigger and Barrel Muon Track Finder systems. • Upgraded system moves from sub-detector centric view to geometric-view. • To improve trigger performance. • Common hardware improves maintainability and increases development speed. • Use of

Upgrade of the CMS muon trigger system in the barrel region

Energy Technology Data Exchange (ETDEWEB)

Rabady, Dinyar, E-mail: dinyar.rabady@cern.ch [Institute of High Energy Physics Vienna (HEPHY), Nikolsdorfer Gasse 18, 1050 Wien (Austria); Ero, Janos [Institute of High Energy Physics Vienna (HEPHY), Nikolsdorfer Gasse 18, 1050 Wien (Austria); Flouris, Giannis [University of Ioannina, 45110 Ioannina (Greece); Fulcher, Jonathan [CERN, 1211 Geneve 23 (Switzerland); Loukas, Nikitas; Paradas, Evangelos [University of Ioannina, 45110 Ioannina (Greece); Reis, Thomas; Sakulin, Hannes; Wulz, Claudia-Elisabeth [CERN, 1211 Geneve 23 (Switzerland)

2017-02-11

To maintain the excellent performance shown during the LHC's Run-1 the Level-1 Trigger of the Compact Muon Solenoid experiment underwent a significant upgrade. One part of this upgrade is the re-organization of the muon trigger path from a subsystem-centric view in which hits in the drift tubes (DT), the cathode strip chambers (CSC), and the resistive plate chambers (RPC) were treated separately in dedicated track-finding systems to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged at the track-finding level. This fundamental restructuring of the muon trigger system required the development of a system to receive track candidates from the track-finding layer, remove potential duplicate tracks, and forward the best candidates to the global decision layer. An overview will be given of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF), as well as the cancel-out and sorting layer: the upgraded Global Muon Trigger (μGMT). Both the BMTF and μGMT have been implemented in a Xilinx Virtex-7 card utilizing the microTCA architecture. While the BMTF improves on the proven and well-tested algorithms used in the Drift Tube Track Finder during Run-1, the μGMT is an almost complete re-development due to the re-organization of the underlying systems from track-finders for a specific detector to regional track finders covering a given area of the whole detector. Additionally the μGMT calculates a muon's isolation using energy information received from the calorimeter trigger. This information is added to the muon objects forwarded to the global decision layer, the so-called Global Trigger. - Highlights: • Presented upgraded Global Muon Trigger and Barrel Muon Track Finder systems. • Upgraded system moves from sub-detector centric view to geometric-view. • To improve trigger performance. • Common hardware improves maintainability and increases development speed. • Use of

The First ATLAS Barrel Toroid Coil Successfully Tested in Hall 180

CERN Multimedia

Rabbers, J J

2004-01-01

The first Barrel Toroid coil has been successfully tested with magnetic mirror at nominal current I=20.5 kA, up to a maximum current Imax=22 kA. After 14 days of cooling down, BT1 reached 4.5 Kelvin and the test program started on September 2nd. First the instrumentation and safety systems of the coil were tested at relatively low operating currents, up to 5 kA. Since all the systems and the coil were performing well, the current was increased by steps in several runs, while monitoring and evaluating the temperatures, voltages and mechanics. On early Wednesday morning September 8th the current was ramped up to 22 kA, shown by the red curve in the picture shown below: Thereafter the current was ramped down by a slow dump, where the stored energy of about 130 MJ is dissipated in a resistor/diode ramp down unit. This is the regular way of ramping down the current, which takes about one hour. Thereafter the current was ramped up to 22 kA for a second time, this time a so-called fast dump was initiated, ...

Readiness of the ATLAS Liquid Argon Calorimeter for LHC Collisions

CERN Document Server

Aad, G.; Abdallah, J.; Abdelalim, A.A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; Acharya, B.S.; Adams, D.L.; Addy, T.N.; Adelman, J.; Adorisio, C.; Adragna, P.; Adye, T.; Aefsky, S.; Aguilar-Saavedra, J.A.; Aharrouche, M.; Ahlen, S.P.; Ahles, F.; Ahmad, A.; Ahmed, H.; Ahsan, M.; Aielli, G.; Akdogan, T.; Akesson, T.P.A.; Akimoto, G.; Akimov, A.V.; Aktas, A.; Alam, M.S.; Alam, M.A.; Albert, J.; Albrand, S.; Aleksa, M.; Aleksandrov, I.N.; Alessandria, F.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Aliev, M.; Alimonti, G.; Alison, J.; Aliyev, M.; Allport, P.P.; Allwood-Spiers, S.E.; Almond, J.; Aloisio, A.; Alon, R.; Alonso, A.; Alviggi, M.G.; Amako, K.; Amelung, C.; Ammosov, V.V.; Amorim, A.; Amorós, G.; Amram, N.; Anastopoulos, C.; Andeen, T.; Anders, C.F.; Anderson, K.J.; Andreazza, A.; Andrei, V.; Anduaga, X.S.; Angerami, A.; Anghinolfi, F.; Anjos, N.; Antonaki, A.; Antonelli, M.; Antonelli, S.; Antunovic, B.; Anulli, F.; Aoun, S.; Arabidze, G.; Aracena, I.; Arai, Y.; Arce, A.T.H.; Archambault, J.P.; Arfaoui, S.; Arguin, J-F; Argyropoulos, T.; Arik, E.; Arik, M.; Armbruster, A.J.; Arnaez, O.; Arnault, C.; Artamonov, A.; Arutinov, D.; Asai, M.; Asai, S.; Asfandiyarov, R.; Ask, S.; Asman, B.; Asner, D.; Asquith, L.; Assamagan, K.; Astbury, A.; Astvatsatourov, A.; Atoian, G.; Auerbach, B.; Auge, E.; Augsten, K.; Aurousseau, M.; Austin, N.; Avolio, G.; Avramidou, R.; Axen, D.; Ay, C.; Azuelos, G.; Azuma, Y.; Baak, M.A.; Baccaglioni, G.; Bacci, C.; Bach, A.; Bachacou, H.; Bachas, K.; Backes, M.; Badescu, E.; Bagnaia, P.; Bai, Y.; Bailey, D.C.; Bain, T.; Baines, J.T.; Baker, O.K.; Baker, M.D.; Baltasar Dos Santos Pedrosa, F; Banas, E.; Banerjee, P.; Banerjee, S.; Banfi, D.; Bangert, A.; Bansal, V.; Baranov, S.P.; Baranov, S.; Barashkou, A.; Barber, T.; Barberio, E.L.; Barberis, D.; Barbero, M.; Bardin, D.Y.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnett, B.M.; Barnett, R.M.; Baron, S.; Baroncelli, A.; Barr, A.J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Barrillon, P.; Barros, N.; Bartoldus, R.; Bartsch, D.; Bastos, J.; Bates, R.L.; Bathe, S.; Batkova, L.; Batley, J.R.; Battaglia, A.; Battistin, M.; Bauer, F.; Bawa, H.S.; Bazalova, M.; Beare, B.; Beau, T.; Beauchemin, P.H.; Beccherle, R.; Becerici, N.; Bechtle, P.; Beck, G.A.; Beck, H.P.; Beckingham, M.; Becks, K.H.; Bedajanek, I.; Beddall, A.J.; Beddall, A.; Bednár, P.; Bednyakov, V.A.; Bee, C.; Begel, M.; Behar Harpaz, S; Behera, P.K.; Beimforde, M.; Belanger-Champagne, C.; Bell, P.J.; Bell, W.H.; Bella, G.; Bellagamba, L.; Bellina, F.; Bellomo, M.; Belloni, A.; Belotskiy, K.; Beltramello, O.; Ben Ami, S; Benary, O.; Benchekroun, D.; Bendel, M.; Benedict, B.H.; Benekos, N.; Benhammou, Y.; Benincasa, G.P.; Benjamin, D.P.; Benoit, M.; Bensinger, J.R.; Benslama, K.; Bentvelsen, S.; Beretta, M.; Berge, D.; Bergeaas Kuutmann, E; Berger, N.; Berghaus, F.; Berglund, E.; Beringer, J.; Bernardet, K.; Bernat, P.; Bernhard, R.; Bernius, C.; Berry, T.; Bertin, A.; Besson, N.; Bethke, S.; Bianchi, R.M.; Bianco, M.; Biebel, O.; Biesiada, J.; Biglietti, M.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Biscarat, C.; Bitenc, U.; Black, K.M.; Blair, R.E.; Blanchard, J-B; Blanchot, G.; Blocker, C.; Blocki, J.; Blondel, A.; Blum, W.; Blumenschein, U.; Bobbink, G.J.; Bocci, A.; Boehler, M.; Boek, J.; Boelaert, N.; Böser, S.; Bogaerts, J.A.; Bogouch, A.; Bohm, C.; Bohm, J.; Boisvert, V.; Bold, T.; Boldea, V.; Boldyrev, A.; Bondarenko, V.G.; Bondioli, M.; Boonekamp, M.; Booth, J.R.A.; Bordoni, S.; Borer, C.; Borisov, A.; Borissov, G.; Borjanovic, I.; Borroni, S.; Bos, K.; Boscherini, D.; Bosman, M.; Bosteels, M.; Boterenbrood, H.; Bouchami, J.; Boudreau, J.; Bouhova-Thacker, E.V.; Boulahouache, C.; Bourdarios, C.; Boyd, J.; Boyko, I.R.; Bozovic-Jelisavcic, I.; Bracinik, J.; Braem, A.; Branchini, P.; Brandenburg, G.W.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J.E.; Braun, H.M.; Brelier, B.; Bremer, J.; Brenner, R.; Bressler, S.; Breton, D.; Brett, N.D.; Britton, D.; Brochu, F.M.; Brock, I.; Brock, R.; Brodbeck, T.J.; Brodet, E.; Broggi, F.; Bromberg, C.; Brooijmans, G.; Brooks, W.K.; Brown, G.; Brubaker, E.; Bruckman de Renstrom, P A; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Buanes, T.; Bucci, F.; Buchanan, J.; Buchholz, P.; Buckley, A.G.; Budagov, I.A.; Budick, B.; Büscher, V.; Bugge, L.; Bulekov, O.; Bunse, M.; Buran, T.; Burckhart, H.; Burdin, S.; Burgess, T.; Burke, S.; Busato, E.; Bussey, P.; Buszello, C.P.; Butin, F.; Butler, B.; Butler, J.M.; Buttar, C.M.; Butterworth, J.M.; Byatt, T.; Caballero, J.; Cabrera Urbán, S; Caforio, D.; Cakir, O.; Calafiura, P.; Calderini, G.; Calfayan, P.; Calkins, R.; Caloba, L.P.; Caloi, R.; Calvet, D.; Camarri, P.; Cambiaghi, M.; Cameron, D.; Campabadal-Segura, F.; Campana, S.; Campanelli, M.; Canale, V.; Canelli, F.; Canepa, A.; Cantero, J.; Capasso, L.; Capeans-Garrido, M.D.M.; Caprini, I.; Caprini, M.; Capua, M.; Caputo, R.; Caracinha, D.; Caramarcu, C.; Cardarelli, R.; Carli, T.; Carlino, G.; Carminati, L.; Caron, B.; Caron, S.; Carrillo Montoya, G D; Carron Montero, S; Carter, A.A.; Carter, J.R.; Carvalho, J.; Casadei, D.; Casado, M.P.; Cascella, M.; Caso, C.; Castaneda Hernadez, A M; Castaneda-Miranda, E.; Castillo Gimenez, V; Castro, N.; Cataldi, G.; Catinaccio, A.; Catmore, J.R.; Cattai, A.; Cattani, G.; Caughron, S.; Cauz, D.; Cavalleri, P.; Cavalli, D.; Cavalli-Sforza, M.; Cavasinni, V.; Ceradini, F.; Cerqueira, A.S.; Cerri, A.; Cerrito, L.; Cerutti, F.; Cetin, S.A.; Cevenini, F.; Chafaq, A.; Chakraborty, D.; Chan, K.; Chapman, J.D.; Chapman, J.W.; Chareyre, E.; Charlton, D.G.; Chavda, V.; Cheatham, S.; Chekanov, S.; Chekulaev, S.V.; Chelkov, G.A.; Chen, H.; Chen, S.; Chen, T.; Chen, X.; Cheng, S.; Cheplakov, A.; Chepurnov, V.F.; Cherkaoui El Moursli, R; Tcherniatine, V.; Chesneanu, D.; Cheu, E.; Cheung, S.L.; Chevalier, L.; Chevallier, F.; Chiarella, V.; Chiefari, G.; Chikovani, L.; Childers, J.T.; Chilingarov, A.; Chiodini, G.; Chizhov, M.; Choudalakis, G.; Chouridou, S.; Chren, D.; Christidi, I.A.; Christov, A.; Chromek-Burckhart, D.; Chu, M.L.; Chudoba, J.; Ciapetti, G.; Ciftci, A.K.; Ciftci, R.; Cinca, D.; Cindro, V.; Ciobotaru, M.D.; Ciocca, C.; Ciocio, A.; Cirilli, M.; Citterio, M.; Clark, A.; Cleland, W.; Clemens, J.C.; Clement, B.; Clement, C.; Clements, D.; Coadou, Y.; Cobal, M.; Coccaro, A.; Cochran, J.; Coelli, S.; Coggeshall, J.; Cogneras, E.; Cojocaru, C.D.; Colas, J.; Cole, B.; Colijn, A.P.; Collard, C.; Collins, N.J.; Collins-Tooth, C.; Collot, J.; Colon, G.; Coluccia, R.; Conde Muiño, P; Coniavitis, E.; Consonni, M.; Constantinescu, S.; Conta, C.; Conventi, F.; Cook, J.; Cooke, M.; Cooper, B.D.; Cooper-Sarkar, A.M.; Cooper-Smith, N.J.; Copic, K.; Cornelissen, T.; Corradi, M.; Corriveau, F.; Corso-Radu, A.; Cortes-Gonzalez, A.; Cortiana, G.; Costa, G.; Costa, M.J.; Costanzo, D.; Costin, T.; Côté, D.; Coura Torres, R; Courneyea, L.; Cowan, G.; Cowden, C.; Cox, B.E.; Cranmer, K.; Cranshaw, J.; Cristinziani, M.; Crosetti, G.; Crupi, R.; Crépé-Renaudin, S.; Cuenca Almenar, C; Cuhadar Donszelmann, T; Curatolo, M.; Curtis, C.J.; Cwetanski, P.; Czyczula, Z.; D'Auria, S.; D'Onofrio, M.; D'Orazio, A.; Da Silva, P V M; Da Via, C; Dabrowski, W.; Dai, T.; Dallapiccola, C.; Dallison, S.J.; Daly, C.H.; Dam, M.; Danielsson, H.O.; Dannheim, D.; Dao, V.; Darbo, G.; Darlea, G.L.; Davey, W.; Davidek, T.; Davidson, N.; Davidson, R.; Davison, A.R.; Dawson, I.; Dawson, J.W.; Daya, R.K.; De, K.; de Asmundis, R; De Castro, S; De Castro Faria Salgado, P E; De Cecco, S; de Graat, J; De Groot, N; de Jong, P; De La Cruz Burelo, E; De La Taille, C; De Mora, L; De Oliveira Branco, M; De Pedis, D; De Salvo, A; De Sanctis, U; De Santo, A; De Vivie De Regie, J B; De Zorzi, G; Dean, S.; Deberg, H.; Dedes, G.; Dedovich, D.V.; Defay, P.O.; Degenhardt, J.; Dehchar, M.; Del Papa, C; Del Peso, J; Del Prete, T; Dell'Acqua, A.; Dell'Asta, L.; Della Pietra, M; della Volpe, D; Delmastro, M.; 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2010-01-01

The ATLAS liquid argon calorimeter has been operating continuously since August 2006. At this time, only part of the calorimeter was readout, but since the beginning of 2008, all calorimeter cells have been connected to the ATLAS readout system in preparation for LHC collisions. This paper gives an overview of the liquid argon calorimeter performance measured in situ with random triggers, calibration data, cosmic muons, and LHC beam splash events. Results on the detector operation, timing performance, electronics noise, and gain stability are presented. High energy deposits from radiative cosmic muons and beam splash events allow to check the intrinsic constant term of the energy resolution. The uniformity of the electromagnetic barrel calorimeter response along eta (averaged over phi) is measured at the percent level using minimum ionizing cosmic muons. Finally, studies of electromagnetic showers from radiative muons have been used to cross-check the Monte Carlo simulation. The performance results obtained u...

Performance of ATLAS L1 Calorimeter Trigger with data

CERN Document Server

Bracinik, J; The ATLAS collaboration

2010-01-01

The ATLAS first-level calorimeter trigger is a hardware-based system designed to identify high-pT jets, electron/photon and tau candidates and to measure total and missing ET in the ATLAS calorimeters. After more than two years of commissioning in situ with calibration data and cosmic rays, the system has now been extensively used to select the most interesting proton-proton collision events. Final tuning of timing and energy calibration has been carried out in 2010 to improve the trigger response to physics objects. An analysis of the performance of the level-1 calorimeter trigger will be presented, along with the techniques used to achieve these results.

Calibration of the ATLAS calorimeters and discovery potential for massive top quark resonances at the LHC

CERN Document Server

Bergeaas Kuutmann, E; Jon-And, K; Hellman, S

2010-01-01

ATLAS is a multi-purpose detector which has recently started to take data at the LHC at CERN. This thesis describes the tests and calibrations of the central calorimeters of ATLAS and outlines a search for heavy top quark pair resonances.The calorimeter tests were performed before the ATLAS detector was assembled at the LHC, in such a way that particle beams of known energy were targeted at the calorimeter modules. In one of the studies presented here, modules of the hadronic barrel calorimeter, TileCal, were exposed to beams of pions of energies between 3 and 9 GeV. It is shown that muons from pion decays in the beam can be separated from the pions, and that the simulation of the detector correctly describes the muon behaviour. In the second calorimeter study, a scheme for local hadronic calibration is developed and applied to single pion test beam data in a wide range of energies, measured by the combination of the electromagnetic barrel calorimeter and the TileCal hadronic calorimeter. The calibration meth...

The Phase II ATLAS ITk Pixel Upgrade

CERN Document Server

Terzo, Stefano; The ATLAS collaboration

2017-01-01

The entire tracking system of the ATLAS experiment will be replaced during the LHC Phase II shutdown (foreseen to take place around 2025) by an all-silicon detector called the "ITk" (Inner Tracker). The innermost portion of ITk will consist of a pixel detector with five layers in the barrel region and and ring-shaped supports in the endcap regions. It will be instrumented with new sensor and readout electronics technologies to improve the tracking performance and cope with the HL-LHC environment, which will be severe in terms of occupancy and radiation. The total surface area of silicon in the new pixel system could measure up to 14 m$^2$ , depending on the final layout choice, which is expected to take place in early 2017. Several layout options are being investigated at the moment, including some with novel inclined support structures in the barrel-endcap overlap region and others with very long innermost barrel layers. Forward coverage could be as high as $|\\eta| < 4$. Supporting structures will be ...

High precision laser control of the ATLAS tile-calorimeter module mass production at JINR

International Nuclear Information System (INIS)

Batusov, V.; Budagov, Yu.; Flyagin, V.; Khubua, D.; Lomakin, Yu.; Lyablin, M.; Rusakovich, N.; Shabalin, D.; Topilin, N.; Nessi, M.

2001-01-01

We present a short description of our last few years experience in the quality control of the ATLAS hadron barrel tile-calorimeter module mass production at JINR. A Laser Measurement System (LMS) proposed and realized in Dubna guarantees a high-precision module assembly. The non-planarity of module size surfaces (1.9x5.6 m) controlled area is well within the required ±0.6 mm tolerance for each of JINR assembled modules. The module assembly technique achieved with the LMS system allows us to deliver to CERN one module every 2 weeks. This laser-based measurement system could be used in future for the control measurement of other large-scale units during the ATLAS assembly

Data Quality system of the ATLAS hadronic Tile calorimeter

International Nuclear Information System (INIS)

Nemecek, Stanislav

2012-01-01

The Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment. It is subdivided into a large central barrel and two smaller lateral extended barrels. Each barrel consists of 64 wedges, made of iron plates and scintillating tiles. Two edges of each scintillating tile are air-coupled to wave-length shifting (WLS) fibres which collect the scintillating light and transmit it to photo-multipliers. The total number of channels is about 10000. An essential part of the TileCal detector is the Data Quality (DQ) system. The DQ system is designed to check the status of the electronic channels. It is designed to provide information at two levels - online and offline. The online TileCal DQ system monitors continuously the data while they are recorded and provides a fast feedback. The offline DQ system allows a detailed study, if needed it provides corrections to be applied to the recorded data and it allows to validate the data for physics analysis. In addition to the check of physics data the TileCal DQ systems also operate with calibration data. The TileCal calibration system provides well defined signals and the response to the calibration signals allows checking the behaviour of the electronic channels in detail. The Monitoring and Calibration Web System supports data quality analyses at the level of channels. All online, offline and calibration versions of the TileCal DQ system also provide automatic tests, the results of which allow fast and robust feedback.

Strip detector for the ATLAS detector upgrade for the High-Luminosity LHC

CERN Document Server

Veloce, Laurelle Maria; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High Luminosity LHC, scheduled for 2025. The expected radiation damage at an integrated luminosity of 3000fb-1 will require the tracking detectors to withstand hadron fluencies to over 1x1016 1 MeV neutron equivalent per cm2. With the addition of increased readout rates, the existing Inner Detector will have to be replaced by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The ITk strip detector consists of a four-layer barrel and a forward region composed of six discs on each side of the barrel. The current prototyping phase has resulted in the ITk Strip Detector Technical Design Report (TDR), which starts the pre-production readiness phase at the involved institutes. In this contribution we present the design of the ITk Strip Detector and current status of R&D of various detector components.

Fast shower simulation in the ATLAS calorimeter

International Nuclear Information System (INIS)

Barberio, E; Boudreau, J; Mueller, J; Tsulaia, V; Butler, B; Young, C C; Cheung, S L; Savard, P; Dell'Acqua, A; Simone, A D; Gallas, M V; Ehrenfeld, W; Glazov, A; Placakyte, R; Marshall, Z; Rimoldi, A; Waugh, A

2008-01-01

The time to simulate pp collisions in the ATLAS detector is largely dominated by the showering of electromagnetic particles in the heavy parts of the detector, especially the electromagnetic barrel and endcap calorimeters. Two procedures have been developed to accelerate the processing time of electromagnetic particles in these regions: (1) a fast shower parameterisation and (2) a frozen shower library. Both work by generating the response of the calorimeter to electrons and positrons with Geant 4, and then reintroduce the response into the simulation at runtime. In the fast shower parameterisation technique, a parameterisation is tuned to single electrons and used later by simulation. In the frozen shower technique, actual showers from low-energy particles are used in the simulation. Full Geant 4 simulation is used to develop showers down to ∼ 1GeV, at which point the shower is terminated by substituting a frozen shower. Judicious use of both techniques over the entire electromagnetic portion of the ATLAS calorimeter produces an important improvement of CPU time. We discuss the algorithms and their performance in this paper

Atlas 1.1: An Update to the Theory of Effective Systems Engineers

Science.gov (United States)

2018-01-16

Proficiency Model ........................................................................................................... 21 5.1.1 Area 1: Math ...which are the most discrete areas of proficiency included in Atlas. • For each proficiency area, there are Levels, which describe the extent to which... Math /Science/General Engineering: Foundational concepts from mathematics, physical sciences, and general engineering; 2. System’s Domain

Evolutions of volatile sulfur compounds of Cabernet Sauvignon wines during aging in different oak barrels.

Science.gov (United States)

Ye, Dong-Qing; Zheng, Xiao-Tian; Xu, Xiao-Qing; Wang, Yun-He; Duan, Chang-Qing; Liu, Yan-Lin

2016-07-01

The evolution of volatile sulfur compounds (VSCs) in Cabernet Sauvignon wines from seven regions of China during maturation in oak barrels was investigated. The barrels were made of different wood grains (fine and medium) and toasting levels (light and medium). Twelve VSCs were quantified by GC/FPD, with dimethyl sulfide (DMS) and methionol exceeding their sensory thresholds. Most VSCs tended to decline during the aging, while DMS was found to increase. After one year aging, the levels of DMS, 2-methyltetrahy-drothiophen-3-one and sulfur-containing esters were lower in the wines aged in oak barrels than in stainless steel tanks. The wood grain and toasting level of oak barrels significantly influenced the concentration of S-methyl thioacetate and 2-methyltetrahy-drothiophen-3-one. This study reported the evolution of VSCs in wines during oak barrel aging for the first time and evaluated the influence of barrel types, which would provide wine-makers with references in making proposals about wine aging. Copyright © 2016 Elsevier Ltd. All rights reserved.

Performance and Operation Experience of the ATLAS SemiConductor Tracker in LHC Run 1 (2009-2012)

CERN Document Server

Robichaud-Veronneau, A; The ATLAS collaboration

2013-01-01

After more than 3 years of successful operation at the LHC, we report on the operation and performance of the Semi-Conductor Tracker (SCT) functioning in a high luminosity, high radiation environment. The SCT is part of the ATLAS experiment at CERN and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibers. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to t...

Commissioning and Validation of the ATLAS Level-1 Topological Trigger in Run 2

CERN Document Server

Zheng, Daniel; The ATLAS collaboration

2017-01-01

The ATLAS experiment has introduced and recently commissioned a completely new hardware sub-system of its first-level trigger: the topological processor (L1Topo). L1Topo consist of two AdvancedTCA blades mounting state-of-the-art FPGA processors, providing high input bandwidth (up to 4 Gb/s) and low latency data processing (200 ns). L1Topo is able to select collision events by applying kinematic and topological requirements on candidate objects (energy clusters, jets, and muons) measured by calorimeters and muon sub-detectors. Results from data recorded using the L1Topo trigger will be presented. These results demonstrate a significantly improved background event rejection, thus allowing for rate reduction with minimal efficiency loss. This improvement has been shown for several physics processes leading to low-$p_T$ leptons, including $H\\rightarrow\\tau \\tau$ and $J/\\psi \\rightarrow \\mu \\mu$. In addition to describing the L1Topo trigger system, we will discuss the use of an accurate L1Topo simulation as a pow...

Using FPGA coprocessor for ATLAS level 2 trigger application

International Nuclear Information System (INIS)

Khomich, Andrei; Hinkelbein, Christian; Kugel, Andreas; Maenner, Reinhard; Mueller, Matthias

2006-01-01

Tracking has a central role in the event selection for the High-Level Triggers of ATLAS. It is particularly important to have fast tracking algorithms in the trigger system. This paper investigates the feasibility of using FPGA coprocessor for speeding up of the TRT LUT algorithm-one of the tracking algorithms for second level trigger for ATLAS experiment (CERN). Two realisations of the same algorithm have been compared: one in C++ and a hybrid C++/VHDL implementation. Using a FPGA coprocessor gives an increase of speed by a factor of two compared to a CPU-only implementation

The e/h ratio of the ATLAS hadronic tile calorimeter

International Nuclear Information System (INIS)

Budagov, Yu.A.; Vinogradov, V.B.; Kul'chitskij, Yu.A.; Kuz'min, M.V.

2002-01-01

We have determined the e/h ratios of the Module-0 of the ATLAS iron-scintillator barrel hadron tile calorimeter for five values of pseudorapidity η in the range of -0.55 ≤ η ≤ -0.15 for the beam energy range from 10 to 300 GeV on the basis of the July 1999 test beam data. These e/h ratios demonstrate independence from |η| value. The mean value is e/h = 1.362 + 0.006. The results are compared with the existing experimental data and with some Monte Carlo calculations

Plasticity-Related Gene 1 Affects Mouse Barrel Cortex Function via Strengthening of Glutamatergic Thalamocortical Transmission.

Science.gov (United States)

Unichenko, Petr; Kirischuk, Sergei; Yang, Jenq-Wei; Baumgart, Jan; Roskoden, Thomas; Schneider, Patrick; Sommer, Angela; Horta, Guilherme; Radyushkin, Konstantin; Nitsch, Robert; Vogt, Johannes; Luhmann, Heiko J

2016-07-01

Plasticity-related gene-1 (PRG-1) is a brain-specific protein that modulates glutamatergic synaptic transmission. Here we investigated the functional role of PRG-1 in adolescent and adult mouse barrel cortex both in vitro and in vivo. Compared with wild-type (WT) animals, PRG-1-deficient (KO) mice showed specific behavioral deficits in tests assessing sensorimotor integration and whisker-based sensory discrimination as shown in the beam balance/walking test and sandpaper tactile discrimination test, respectively. At P25-31, spontaneous network activity in the barrel cortex in vivo was higher in KO mice compared with WT littermates, but not at P16-19. At P16-19, sensory evoked cortical responses in vivo elicited by single whisker stimulation were comparable in KO and WT mice. In contrast, at P25-31 evoked responses were smaller in amplitude and longer in duration in WT animals, whereas KO mice revealed no such developmental changes. In thalamocortical slices from KO mice, spontaneous activity was increased already at P16-19, and glutamatergic thalamocortical inputs to Layer 4 spiny stellate neurons were potentiated. We conclude that genetic ablation of PRG-1 modulates already at P16-19 spontaneous and evoked excitability of the barrel cortex, including enhancement of thalamocortical glutamatergic inputs to Layer 4, which distorts sensory processing in adulthood. © The Author 2016. Published by Oxford University Press.

Scaling up ATLAS Event Service to production levels on opportunistic computing platforms

CERN Document Server

Benjamin, Douglas; The ATLAS collaboration; Ernst, Michael; Guan, Wen; Hover, John; Lesny, David; Maeno, Tadashi; Nilsson, Paul; Tsulaia, Vakhtang; van Gemmeren, Peter; Vaniachine, Alexandre; Wang, Fuquan; Wenaus, Torre

2016-01-01

Continued growth in public cloud and HPC resources is on track to overcome the dedicated resources available for ATLAS on the WLCG. Example of such platforms are Amazon AWS EC2 Spot Instances, Edison Cray XC30 supercomputer, backfill at the Tier-2 and Tier-3 sites, opportunistic resources at the Open Science Grid, and ATLAS High Level Trigger farm between the data taking periods. Because of opportunistic resources specifics such as preemptive job scheduling and data I/O, their efficient usage requires workflow innovations provided by the ATLAS Event Service. Thanks to the finer granularity of the Event Service data processing workflow, the opportunistic resources are used more efficiently. We report on our progress in scaling opportunistic resource usage to double-digit levels in ATLAS production.

ATLAS operations in the GridKa T1/T2 Cloud

International Nuclear Information System (INIS)

Duckeck, G; Serfon, C; Walker, R; Harenberg, T; Kalinin, S; Schultes, J; Kawamura, G; Leffhalm, K; Meyer, J; Nderitu, S; Olszewski, A; Petzold, A; Sundermann, J E

2011-01-01

The ATLAS GridKa cloud consists of the GridKa Tier1 centre and 12 Tier2 sites from five countries associated to it. Over the last years a well defined and tested operation model evolved. Several core cloud services need to be operated and closely monitored: distributed data management, involving data replication, deletion and consistency checks; support for ATLAS production activities, which includes Monte Carlo simulation, reprocessing and pilot factory operation; continuous checks of data availability and performance for user analysis; software installation and database setup. Of crucial importance is good communication between sites, operations team and ATLAS as well as efficient cloud level monitoring tools. The paper gives an overview of the operations model and ATLAS services within the cloud.

Monitoring core barrel motion by neutron noise diagnostics

International Nuclear Information System (INIS)

Por, G.

1985-08-01

The core barrel motion is detected by ionization chambers located around the reactor vessel. The method is based on the measurement of the neutron flux fluctuations. Calculations to determine the direction and the size of the motion are discussed. The identification of core barrel motion and its connection with the error of one of the main circulating pumps in the Rheinsberg nuclear power plant are described. Core barrel motion of 10 Hz with an amplitude less than 50 μm could be diagnozed at the Paks-1 reactor using the Dutch high accuracy evaluation system. (V.N.)

Study of surface properties of ATLAS12 strip sensors and their radiation resistance

Energy Technology Data Exchange (ETDEWEB)

Mikestikova, M., E-mail: mikestik@fzu.cz [Academy of Sciences of the Czech Republic, Institute of Physics, Na Slovance 2, 18221 Prague 8 (Czech Republic); Allport, P.P.; Baca, M.; Broughton, J.; Chisholm, A.; Nikolopoulos, K.; Pyatt, S.; Thomas, J.P.; Wilson, J.A. [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom); Kierstead, J.; Kuczewski, P.; Lynn, D. [Brookhaven National Laboratory, Physics Department and Instrumentation Division, Upton, NY 11973-5000 (United States); Hommels, L.B.A. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Ullan, M. [Centro Nacional de Microelectronica (IMB-CNM, CSIC), Campus UAB-Bellaterra, 08193 Barcelona (Spain); Bloch, I.; Gregor, I.M.; Tackmann, K. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Hauser, M.; Jakobs, K.; Kuehn, S. [Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); and others

2016-09-21

A radiation hard n{sup +}-in-p micro-strip sensor for the use in the Upgrade of the strip tracker of the ATLAS experiment at the High Luminosity Large Hadron Collider (HL-LHC) has been developed by the “ATLAS ITk Strip Sensor collaboration” and produced by Hamamatsu Photonics. Surface properties of different types of end-cap and barrel miniature sensors of the latest sensor design ATLAS12 have been studied before and after irradiation. The tested barrel sensors vary in “punch-through protection” (PTP) structure, and the end-cap sensors, whose stereo-strips differ in fan geometry, in strip pitch and in edge strip ganging options. Sensors have been irradiated with proton fluences of up to 1×10{sup 16} n{sub eq}/cm{sup 2}, by reactor neutron fluence of 1×10{sup 15} n{sub eq}/cm{sup 2} and by gamma rays from {sup 60}Co up to dose of 1 MGy. The main goal of the present study is to characterize the leakage current for micro-discharge breakdown voltage estimation, the inter-strip resistance and capacitance, the bias resistance and the effectiveness of PTP structures as a function of bias voltage and fluence. It has been verified that the ATLAS12 sensors have high breakdown voltage well above the operational voltage which implies that different geometries of sensors do not influence their stability. The inter-strip isolation is a strong function of irradiation fluence, however the sensor performance is acceptable in the expected range for HL-LHC. New gated PTP structure exhibits low PTP onset voltage and sharp cut-off of effective resistance even at the highest tested radiation fluence. The inter-strip capacitance complies with the technical specification required before irradiation and no radiation-induced degradation was observed. A summary of ATLAS12 sensors tests is presented including a comparison of results from different irradiation sites. The measured characteristics are compared with the previous prototype of the sensor design, ATLAS07. - Highlights: �

A readout buffer prototype for ATLAS high-level triggers

CERN Document Server

Calvet, D; Huet, M; Le Dû, P; Mandjavidze, I D; Mur, M

2001-01-01

Readout buffers are critical components in the dataflow chain of the ATLAS trigger/data-acquisition system. At up to 75 kHz, after each Level-1 trigger accept signal, these devices receive and store digitized data from groups of front-end electronic channels. Several readout buffers are grouped to form a readout buffer complex that acts as a data server for the high-level trigger selection algorithms and for the final data-collection system. This paper describes a functional prototype of a readout buffer based on a custom-made PCI mezzanine card that is designed to accept input data at up to 160 MB /s, to store up to 8 MB of data, and to distribute data chunks at the desired request rate. We describe the hardware of the card that is based on an Intel 1960 processor and complex programmable logic devices. We present the integration of several of these cards in a readout buffer complex. We measure various performance figures and discuss to which extent these can fulfil ATLAS needs. (5 refs).

Completion of the TRT Barrel

CERN Multimedia

Gagnon, P

On February 3, the US-TRT team proudly completed the installation of the 96th barrel TRT module on its support structure in the SR building at CERN. This happy event came after many years of R&D initiated in the nineties by the TA1 team at CERN, followed by the construction of the modules in three American institutes (Duke, Hampton and Indiana Universities) from 1996 to 2003. In total, the 96 barrel modules contain 52544 kapton straws, each 4 mm in diameter and strung with a 30 micron gold-plated tungsten wire. Each wire was manually inserted, a feat in itself! The inner layer modules contain 329 straws, the middle layer modules have 520 straws and the outer layer, 793 straws. Thirty- two modules of each type form a full layer. Their special geometry was designed such as to leave no dead region. On average, a particle will cross 36 straws. Kirill Egorov, Chuck Mahlon and John Callahan inserted the last module in the Barrel Support Structure. After completion in the US, all modules were transferred...

Study of ZZ to four leptons events in ATLAS at the LHC and upgrade of the ATLAS Muon Spectrometer

CERN Multimedia

Kouskoura, V

2014-01-01

The study of the ZZ and ZZ* production in proton-proton collisions at the Large Hadron Collider (LHC) at CERN is presented. The data analyzed in this study were recorded by the ATLAS experiment at a centre-of-mass energy of 7 TeV and of 8 TeV. The selected events are consistent with fully leptonic ZZ decays, in particular to electrons and muons. The total ZZ production cross section is measured and is found to be in agreement with the Standard Model (SM) prediction. The ZZ production allows the study of the anomalous neutral Triple Gauge Couplings. No deviation from the SM prediction is found that could indicate the presence of New Physics. In view of the forthcoming increase of the instantaneous luminosity of the LHC, the ATLAS Collaboration foresees upgrades of the detector. An upgrade of the Muon Spectrometer is presented. The integration of the new detection elements in the ATLAS Geometry is illustrated, as well as the increase in the total Barrel acceptance.

Scaling up ATLAS Event Service to production levels on opportunistic computing platforms

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00066086; The ATLAS collaboration; Caballero, Jose; Ernst, Michael; Guan, Wen; Hover, John; Lesny, David; Maeno, Tadashi; Nilsson, Paul; Tsulaia, Vakhtang; van Gemmeren, Peter; Vaniachine, Alexandre; Wang, Fuquan; Wenaus, Torre

2016-01-01

Continued growth in public cloud and HPC resources is on track to exceed the dedicated resources available for ATLAS on the WLCG. Examples of such platforms are Amazon AWS EC2 Spot Instances, Edison Cray XC30 supercomputer, backfill at Tier 2 and Tier 3 sites, opportunistic resources at the Open Science Grid (OSG), and ATLAS High Level Trigger farm between the data taking periods. Because of specific aspects of opportunistic resources such as preemptive job scheduling and data I/O, their efficient usage requires workflow innovations provided by the ATLAS Event Service. Thanks to the finer granularity of the Event Service data processing workflow, the opportunistic resources are used more efficiently. We report on our progress in scaling opportunistic resource usage to double-digit levels in ATLAS production.

Radiation induced effects in the \\\\ATLAS Insertable B-Layer readout chip

CERN Document Server

The ATLAS collaboration

2017-01-01

The ATLAS Insertable B-Layer is the innermost pixel barrel layer of the ATLAS detector installed in 2014. During the first year of $pp$ collisions at $\\sqrt{s} = 13~{\\rm TeV}$ in 2015, an unusual increase was observed in the low voltage currents of the readout chips. This increase was found to be due to radiation damage to the chips. The dependence of the current on the total ionising dose and temperature has been studied using X-ray and proton beam sources, and will be presented in this note together with its possible parametrisation and operation guidelines for the detector.

Design and test of a prototype silicon detector module for ATLAS Semiconductor Tracker endcaps

International Nuclear Information System (INIS)

Clark, A.G.; Donega, M.; D'Onofrio, M.

2005-01-01

The ATLAS Semiconductor Tracker (SCT) will be a central part of the tracking system of the ATLAS experiment. The SCT consists of four concentric barrels of silicon detectors as well as two silicon endcap detectors formed by nine disks each. The layout of the forward silicon detector module presented in this paper is based on the approved layout of the silicon detectors of the SCT, their geometry and arrangement in disks, but uses otherwise components identical to the barrel modules of the SCT. The module layout is optimized for excellent thermal management and electrical performance, while keeping the assembly simple and adequate for a large scale module production. This paper summarizes the design and layout of the module and present results of a limited prototype production, which has been extensively tested in the laboratory and testbeam. The module design was not finally adopted for series production because a dedicated forward hybrid layout was pursued

CMS Barrel Pixel Detector Overview

CERN Document Server

Kästli, H C; Erdmann, W; Gabathuler, K; Hörmann, C; Horisberger, Roland Paul; König, S; Kotlinski, D; Meier, B; Robmann, P; Rohe, T; Streuli, S

2007-01-01

The pixel detector is the innermost tracking device of the CMS experiment at the LHC. It is built from two independent sub devices, the pixel barrel and the end disks. The barrel consists of three concentric layers around the beam pipe with mean radii of 4.4, 7.3 and 10.2 cm. There are two end disks on each side of the interaction point at 34.5 cm and 46.5 cm. This article gives an overview of the pixel barrel detector, its mechanical support structure, electronics components, services and its expected performance.

Method for a top quark mass measurement with the ATLAS detector at LHC: Study of the ATLAS level-1 electromagnetic calorimeter trigger

International Nuclear Information System (INIS)

Marzin, A.

2010-01-01

The ATLAS detector at the LHC (CERN) is designed to study the Standard Model, with the precise measurement of its parameters and the search of the Higgs boson, and the physics beyond the Standard Model with the search of new particles predicted by several theories such as Supersymmetry. The top quark is distinguished in the Standard Model by its mass close to the scale of electroweak symmetry breaking and is therefore a good probe to study physics beyond the Standard Model. A precise measurement of the top quark mass is also required to constrain the mass of the Higgs boson via the radiative corrections to the W boson propagator what would be a test of consistency of the standard Model if the Higgs boson is discovered. The first part of this thesis presents the theoretical aspects of the top quark mass. The second part is devoted to the calibration of the ATLAS level-1 electromagnetic calorimeter trigger, and more specifically to the processing of the analogue signal coming form the calorimeter. The performances of this system with cosmic muons and first LHC collisions are also described. At last, the third part describes the methods for a top quark mass measurement which have been developed in the lepton plus jets and dilepton channels. (author) [fr

Semiconductor tracker final integration and commissioning in the ATLAS detector

International Nuclear Information System (INIS)

Robichaud-Veronneau, Andree

2008-01-01

The SemiConductor Tracker (SCT) is part of the Inner Detector of the ATLAS experiment at the LHC. It is located between the Pixel detector and the Transition Radiation Tracker (TRT). During 2006 and 2007, the SCT was installed in its final position inside the ATLAS detector. The SCT barrel was lowered in 2006 and was tested for connectivity and noise. Common tests with the TRT to look for pick-up noise and grounding issues were also performed. The SCT end-caps were installed during summer 2007 and will undergo similar checks. The results from the various tests done before and after installation will be presented here.

The ATLAS Liquid Argon Electromagnetic EndCap Calorimeter Construction and tests

CERN Document Server

Rodier, S; Del Peso, J

2003-01-01

This thesis has been carried out within the ATLAS collaboration. ATLAS is one of the two multipurpose experiments approved for data taking at the Large Hadron Collider (LHC) at CERN. The main goals of this experiment are, to find the Higgs boson, the missing piece in the otherwise so succesful Standard Model of Particle Physics, and to look for physics beyond the Standard Model up to a scale of 1TeV. For this purpose, electromagnetic (EM) calorimetry play a key role. The ATLAS Collaboration has chosen a Liquid Argon (LAr) option with lead as passive material. The liquid Argon Calorimeter is divided into two main subdetectors, the barrel and the end caps (EC). The design and construction of the LAr EM EC calorimeter is the responsability of the groups at Centre de Physique de Marseille (CPPM) and the Universidad Autonoma de Madrid (UAM)following the guideline developed by the research and development working, group 3 for LHC detectors (RD3). The sharing of responsabilities is such that CPPM provides spacers an...

Level-1 Data Driver Card of the ATLAS New Small Wheel upgrade compatible with the Phase II 1 MHz readout scheme

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00549793; The ATLAS collaboration

2016-01-01

The Level-1 Data Driver Card (L1DDC) will be designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The L1DDC is a high speed aggregator board capable of communicating with a large number of front-end electronics. It collects the Level-1 data along with monitoring data and transmits them to a network interface through a single bidirectional fiber link. In addition, the L1DDC board distributes trigger, time and configuration data coming from the network interface to the front-end boards. The L1DDC is fully compatible with the Phase II upgrade where the trigger rate is expected to reach 1 MHz. This paper describes the overall scheme of the data acquisition process and especially the three different L1DDC boards that will be fabricated. Moreover the L1DDC prototype-1 is also described.

Engineering for the ATLAS SemiConductor Tracker (SCT) End-cap

Energy Technology Data Exchange (ETDEWEB)

Abdesselam, A; Barr, A [Department of Physics, Oxford University, Oxford (United Kingdom); Allport, P P [Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Anderson, B [Department of Physics, University College, University of London, London (United Kingdom); Andricek, L; Becker, H [Max-Planck-Institut fuer Physik, Muenchen (Germany); Anghinolfi, F [European Laboratory for Particle Physics (CERN), Geneva (Switzerland); Apsimon, R J; Austin, A; Barclay, P; Batchelor, L E; Benes, J [Centro Nacional de Microelectronica de Barcelona, CNM-IMB, CSIC, Barcelona (Spain); Atkinson, T [University of Melbourne, Parkville, Victoria 3052 (Australia); Band, H [NIKHEF, Amsterdam (Netherlands); Bates, R L; Bell, W H [Department of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Batley, J R [Cavendish Laboratory, Cambridge University, Cambridge (United Kingdom); Beck, G; Belymam, A [Department of Physics, Queen Mary and Westfield College, University of London, London (United Kingdom); Bell, P [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom)], E-mail: S.J.Haywood@rl.ac.uk (and others)

2008-05-15

The ATLAS SemiConductor Tracker (SCT) is a silicon-strip tracking detector which forms part of the ATLAS inner detector. The SCT is designed to track charged particles produced in proton-proton collisions at the Large Hadron Collider (LHC) at CERN at an energy of 14 TeV. The tracker is made up of a central barrel and two identical end-caps. The barrel contains 2112 silicon modules, while each end-cap contains 988 modules. The overall tracking performance depends not only on the intrinsic measurement precision of the modules but also on the characteristics of the whole assembly, in particular, the stability and the total material budget. This paper describes the engineering design and construction of the SCT end-caps, which are required to support mechanically the silicon modules, supply services to them and provide a suitable environment within the inner detector. Critical engineering choices are highlighted and innovative solutions are presented - these will be of interest to other builders of large-scale tracking detectors. The SCT end-caps will be fully connected at the start of 2008. Further commissioning will continue, to be ready for proton-proton collision data in 2008.

Core barrel inner tube lifter

Energy Technology Data Exchange (ETDEWEB)

Jeffers, J P

1968-07-16

A core drill with means for selectively lifting a core barrel inner tube consists of a lifting means connected to the core barrel inner tube assembly. It has a closable passage to permit drilling fluid normally to pass through it. The lifting means has a normally downward facing surface and a means to direct drilling fluid pressure against that surface so that on closure of the passage to fluid flow, the pressure of the drilling fluid is caused to act selectively on it. This causes the lifting means to rise and lift the core barrel. (7 claims)

Electron response and e/h ratio of ATLAS barrel hadron prototype calorimeter

International Nuclear Information System (INIS)

Budagov, Yu.A.; Vinogradov, V.B.; Arkadov, V.V.; Karapetyan, G.V.

1995-01-01

The detailed information about electron response, electron energy resolution and e/h ratio as a function of incident energy E, impact point Z and incidence angle Θ of ATLAS iron-scintillator hadron prototype calorimeter with longitudinal tile configuration is presented. These results are based on electron and pion beams data of E=20, 50, 100, 150, 300 GeV at Θ=10 deg, 20 deg, 30 deg, which were obtained during test beam period in July 1995. The obtained calibration constant is used for muon response converting from pC to GeV. The results are compared with existing experimental data and with some Monte Carlo calculations. For some E, Θ, Z values the compensation (e/h=1) is observed. 23 refs., 18 figs., 9 tabs

The ATLAS High-Level Calorimeter Trigger in Run-2

CERN Document Server

Wiglesworth, Craig; The ATLAS collaboration

2018-01-01

The ATLAS Experiment uses a two-level triggering system to identify and record collision events containing a wide variety of physics signatures. It reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of 1 kHz, whilst maintaining high efficiency for interesting collision events. It is composed of an initial hardware-based level-1 trigger followed by a software-based high-level trigger. A central component of the high-level trigger is the calorimeter trigger. This is responsible for processing data from the electromagnetic and hadronic calorimeters in order to identify electrons, photons, taus, jets and missing transverse energy. In this talk I will present the performance of the high-level calorimeter trigger in Run-2, noting the improvements that have been made in response to the challenges of operating at high luminosity.

Beamtest results of ATLAS SCT Modules in 2002

CERN Document Server

Barr, A J; Dolezal, Z; Donega, M; D'Onofrio, M; García, J E; González, S; Horazdovsky, T; Kazi, S; Kodys, P; Moorhead, G F; Reznicek, P; Solar, M; Vos, M; Wallny, R

2004-01-01

Beamtests of ATLAS Semiconductor Tracker (SCT) modules carried out at the ATLAS testbeam facility at the CERN SPS H8. During 2002, three beam runs were carried out in May/June, July and August. In the August 2002 beam test period four irradiated modules, two ``K5'' end-cap and two barrel, with the final design were tested. Module propierties (efficiency, charge collection, signal/noise, pulse shape) and the dependence of them for a particle high incidence angle was studied. A comparison with previous testbeam results was also performed. Time-stamping performance of SCT modules and specially, the effect of irradiation on the time characteristics of the Front End was investigated more closely. On this note we show a summary of these studies.

ATLAS High Level Calorimeter Trigger Software Performance for Cosmic Ray Events

CERN Document Server

Oliveira Damazio, Denis; The ATLAS collaboration

2009-01-01

The ATLAS detector is undergoing intense commissioning effort with cosmic rays preparing for the first LHC collisions next spring. Combined runs with all of the ATLAS subsystems are being taken in order to evaluate the detector performance. This is an unique opportunity also for the trigger system to be studied with different detector operation modes, such as different event rates and detector configuration. The ATLAS trigger starts with a hardware based system which tries to identify detector regions where interesting physics objects may be found (eg: large energy depositions in the calorimeter system). An approved event will be further processed by more complex software algorithms at the second level where detailed features are extracted (full detector granularity data for small portions of the detector is available). Events accepted at this level will be further processed at the so-called event filter level. Full detector data at full granularity is available for offline like processing with complete calib...

Start of Final Assembly of the CMS Barrel Yoke on schedule at P5 the 1st august, 2000. I

CERN Multimedia

Hubert Gerwig, CERN/ EP-CMI

2000-01-01

The Barrel Yoke and the vacuumtank weigh 6500 tonnes. The barrel Yoke consists of 5 rings eacu one weighing 1200 tonnes. The vacuum tank is a stainless steel structure weighing 270 tonnes (length = 13 m , outer diamter 7.6 m) The final assembly of these items will take approximately 1 year from now on.

Development of the ATLAS High-Level Trigger Steering and Inclusive Searches for Supersymmetry

CERN Document Server

Eifert, T

2009-01-01

The presented thesis is divided into two distinct parts. The subject of the first part is the ATLAS high-level trigger (HLT), in particular the development of the HLT Steering, and the trigger user-interface. The second part presents a study of inclusive supersymmetry searches, including a novel background estimation method for the relevant Standard Model (SM) processes. The trigger system of the ATLAS experiment at the Large Hadron Collider (LHC) performs the on-line physics selection in three stages: level-1 (LVL1), level-2 (LVL2), and the event filter (EF). LVL2 and EF together form the HLT. The HLT receives events containing detector data from high-energy proton (or heavy ion) collisions, which pass the LVL1 selection at a maximum rate of 75 kHz. It must reduce this rate to ~200 Hz, while retaining the most interesting physics. The HLT is a software trigger and runs on a large computing farm. At the heart of the HLT is the Steering software. The HLT Steering must reach a decision whether or not to accept ...

ATLAS silicon microstrip detector system (SCT)

International Nuclear Information System (INIS)

Unno, Y.

2003-01-01

The S CT together with the pixel and the transition radiation tracker systems and with a central solenoid forms the central tracking system of the ATLAS detector at LHC. Series production of SCT Silicon microstrip sensors is near completion. The sensors have been shown to be robust against high voltage operation to the 500 V required after fluences of 3x10 14 protons/cm 2 . SCT barrel modules are in series production. A low-noise CCD camera has been used to debug the onset of leakage currents

A read-out buffer prototype for ATLAS high level triggers

CERN Document Server

Calvet, D; Huet, M; Le Dû, P; Mandjavidze, I D; Mur, M

2000-01-01

Read-Out Buffers are critical components in the dataflow chain of the ATLAS Trigger/DAQ system. At up to 75 kHz, after each Level-1 trigger accept signal, these devices receive and store digitized data from groups of front-end electronic channels. Several Read-Out Buffers are grouped to form a Read-Out Buffer Complex that acts as a data server for the High Level Triggers selection algorithms and for the final data collection system. This paper describes a functional prototype of a Read-Out Buffer based on a custom made PCI mezzanine card that is designed to accept input data at up to 160 MB/s, to store up to 8 MB of data and to distribute data chunks at the desired request rate. We describe the hardware of the card that is based on an Intel I960 processor and CPLDs. We present the integration of several of these cards in a Read-Out Buffer Complex. We measure various performance figures and we discuss to which extent these can fulfill ATLAS needs. 5 Refs.

ATLAS Tile Calorimeter extended barrel Side A assembly and installation in the cavern.

CERN Multimedia

Nikolai Topilin

2009-01-01

These photos belong to the self-published book by Nikolai Topilin "ATLAS Hadron Calorimeter Assembly". The book is a collection of souvenirs from the years of assembly and installation of the Tile Hadron Calorimeter, which extended from November 2002 until May 2006.

ATLAS Tile Calorimeter extended barrel side C, assembly and installation in the cavern.

CERN Multimedia

Nikolai Topilin

2009-01-01

These photos belong to the self-published book by Nikolai Topilin "ATLAS Hadron Calorimeter Assembly". The book is a collection of souvenirs from the years of assembly and installation of the Tile Hadron Calorimeter, which extended from November 2002 until May 2006.

Studies of radial distortions of the ATLAS Inner Detector

CERN Document Server

The ATLAS collaboration

2018-01-01

The measurement of the absolute momentum scale of charged particles provided by the ATLAS inner detector is affected by biases related to geometrical deformations which are not well constrained by the track-based alignment procedure. The focus of this note is on momentum biases related to radial distortions of the inner detector. The $J/\\psi$, $\\Upsilon$, and $Z$-boson resonances decaying into pairs of muons are used to study and quantify such radial distortions in the barrel region of the inner detector. The analysis is performed on data collected in 2016 during Run 2 of the Large Hadron Collider, and corresponding to 33 fb$^{-1}$ of integrated luminosity.

Multi-threading in the ATLAS High-Level Trigger

CERN Document Server

Barton, Adam Edward; The ATLAS collaboration

2018-01-01

Over the next decade of LHC data-taking the instantaneous luminosity will reach up 7.5 times the design value with over 200 interactions per bunch-crossing and will pose unprecedented challenges for the ATLAS trigger system. With the evolution of the CPU market to many-core systems, both the ATLAS offline reconstruction and High-Level Trigger (HLT) software will have to transition from a multi-process to a multithreaded processing paradigm in order not to exhaust the available physical memory of a typical compute node. The new multithreaded ATLAS software framework, AthenaMT, has been designed from the ground up to support both the offline and online use-cases with the aim to further harmonize the offline and trigger algorithms. The latter is crucial both in terms of maintenance effort and to guarantee the high trigger efficiency and rejection factors needed for the next two decades of data-taking. We report on an HLT prototype in which the need for HLT­specific components has been reduced to a minimum while...

Upgrade of the ATLAS Level‐1 trigger with an FPGA based Topological Processor

CERN Document Server

Caputo, R; The ATLAS collaboration; Buescher, V; Degele, R; Kiese, P; Maldaner, S; Reiss, A; Schaefer, U; Simioni, E; Tapprogge, S; Urejola, P

2013-01-01

The ATLAS experiment is located at the European Centre for Nuclear Research (CERN) in Switzerland. It is designed to measure decay properties of high energetic particles produced in the protons collisions at the Large Hadron Collider (LHC). LHC proton collision at a frequency of 40 MHz, requires a trigger system to efficiently select events down to a manageable event storage rate of about 400 Hz. Event triggering is therefore one of the extraordinary challenges faced by the ATLAS detector. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 75kHz and decision latency of less than 2.5$\\mu$s. It is primarily composed of the Calorimeter Trigger, Muon Trigger, the Central Trigger Processor (CTP). Due to the increase in the LHC instantaneous luminosity up to 3$\\times$10$^{34}$cm$^{−2}$s$^{−1}$ in 2015, a new element will be included in the Level-1 Trigger scheme: the Topological Processor (L1Topo). The L1Topo receive data in a dedicated format from the calorimeters ...

ATLAS tile calorimeter cesium calibration control and analysis software

International Nuclear Information System (INIS)

Solovyanov, O; Solodkov, A; Starchenko, E; Karyukhin, A; Isaev, A; Shalanda, N

2008-01-01

An online control system to calibrate and monitor ATLAS Barrel hadronic calorimeter (TileCal) with a movable radioactive source, driven by liquid flow, is described. To read out and control the system an online software has been developed, using ATLAS TDAQ components like DVS (Diagnostic and Verification System) to verify the hardware before running, IS (Information Server) for data and status exchange between networked computers, and other components like DDC (DCS to DAQ Connection), to connect to PVSS-based slow control systems of Tile Calorimeter, high voltage and low voltage. A system of scripting facilities, based on Python language, is used to handle all the calibration and monitoring processes from hardware perspective to final data storage, including various abnormal situations. A QT based graphical user interface to display the status of the calibration system during the cesium source scan is described. The software for analysis of the detector response, using online data, is discussed. Performance of the system and first experience from the ATLAS pit are presented

ATLAS tile calorimeter cesium calibration control and analysis software

Energy Technology Data Exchange (ETDEWEB)

Solovyanov, O; Solodkov, A; Starchenko, E; Karyukhin, A; Isaev, A; Shalanda, N [Institute for High Energy Physics, Protvino 142281 (Russian Federation)], E-mail: Oleg.Solovyanov@ihep.ru

2008-07-01

An online control system to calibrate and monitor ATLAS Barrel hadronic calorimeter (TileCal) with a movable radioactive source, driven by liquid flow, is described. To read out and control the system an online software has been developed, using ATLAS TDAQ components like DVS (Diagnostic and Verification System) to verify the hardware before running, IS (Information Server) for data and status exchange between networked computers, and other components like DDC (DCS to DAQ Connection), to connect to PVSS-based slow control systems of Tile Calorimeter, high voltage and low voltage. A system of scripting facilities, based on Python language, is used to handle all the calibration and monitoring processes from hardware perspective to final data storage, including various abnormal situations. A QT based graphical user interface to display the status of the calibration system during the cesium source scan is described. The software for analysis of the detector response, using online data, is discussed. Performance of the system and first experience from the ATLAS pit are presented.

Yucca Mountain Project Site Atlas: Volume 1: Draft

International Nuclear Information System (INIS)

1988-10-01

The Nevada Nuclear Waste Storage Investigations (NNWSI) Project Site Atlas is a reference document of field activities which have been, or are being, conducted by the US Department of Energy (DOE) to support investigations of Yucca Mountain as a potential site for an underground repository for high-level radioactive waste. These investigations, as well as future investigations, will yield geologic, geophysical, geochemical, geomechanical, hydrologic, volcanic, seismic, and environmental data necessary to characterize Yucca Mountain and its regional setting. This chapter summarizes the background of the NNWSI Project and the objective, scope, structure, and preparation of the Site Atlas. Chapter 2 describes in more detail the bibliography and map portfolio portions of the Atlas, which are presented in Chapter 4 and Volume 2, respectively. Chapter 3 describes how to use the Atlas. The objective of the Site Atlas is to create a management tool for the DOE Waste Management Project Office (WMPO) that will allow the WMPO to compile and disseminate information regarding the location of NNWSI Project field investigations, and document the permits acquired and the environmental, archaeological, and socioeconomic surveys conducted to support those investigations. The information contained in the Atlas will serve as a historical reference of site investigation field activities. A companion document to the Atlas is the NNWSI Project Surface Based Investigations Plan (SBIP)

Commissioning of the ATLAS High Level Trigger with single beam and cosmic rays

International Nuclear Information System (INIS)

Di Mattia, A

2010-01-01

ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). The trigger system is responsible for making the online selection of interesting collision events. At the LHC design luminosity of 10 34 cm -2 s -1 it will need to achieve a rejection factor of the order of 10 -7 against random proton-proton interactions, while selecting with high efficiency events that are needed for physics analyses. After a first processing level using custom electronics based on FPGAs and ASICs, the trigger selection is made by software running on two processor farms, containing a total of around two thousand multi-core machines. This system is known as the High Level Trigger (HLT). To reduce the network data traffic and the processing time to manageable levels, the HLT uses seeded, step-wise reconstruction, aiming at the earliest possible rejection of background events. The recent LHC startup and short single-beam run provided a 'stress test' of the system and some initial calibration data. Following this period, ATLAS continued to collect cosmic-ray events for detector alignment and calibration purposes. After giving an overview of the trigger design and its innovative features, this paper focuses on the experience gained from operating the ATLAS trigger with single LHC beams and cosmic-rays.

Commissioning Test of ATLAS End-Cap Toroidal Magnets

CERN Document Server

Dudarev, A; Foussat, A; Benoit, P; Jeckel, M; Olyunin, A; Kopeykin, N; Stepanov, V; Deront, L; Olesen, G; Ponts, X; Ravat, S; Sbrissa, K; Barth, J; Bremer, J; Delruelle, J; Metselaar, J; Pengo, R; Pirotte, O; Buskop, J; Baynham, D E; Carr, F S; Holtom, E

2009-01-01

The system of superconducting toroids in the ATLAS experiment at CERN consists of three magnets. The Barrel Toroid was assembled and successfully tested in 2006. Next, two End-Cap Toroids have been tested on surface at 77 K and installed in the cavern, 100-m underground. The End Cap Toroids are based on Al stabilized Nb-Ti/Cu Rutherford cables, arranged in double pancake coils and conduction cooled at 4.6 K. The nominal current is 20.5 kA at 4.1 T peak field in the windings and the stored energy is 250 MJ per toroid. Prior to final testing of the entire ATLAS Toroidal system, each End Cap Toroid passed a commissioning test up to 21 kA to guarantee a reliable performance in the final assembly. In this paper the test results are described. It includes the stages of test preparation, isolation vacuum pumping and leak testing, cooling down, step-by-step charging to full current, training quenches and quench recovery. By fast discharges the quench detection and protection system was checked to demonstrate a safe e...

Status of the ATLAS Liquid Argon Calorimeter and its performance after one year of LHC operation

CERN Document Server

"March, L; The ATLAS collaboration

2011-01-01

The ATLAS experiment is designed to study the proton-proton collisions produced at the LHC with a centre-of-mass energy of 14 TeV. Liquid argon (LAr) sampling calorimeters are used in ATLAS for all electromagnetic calorimetry and partly for hadronic calorimetry. The calorimeter system consists of an electromagnetic barrel calorimeter and two endcaps with electromagnetic (EMEC), hadronic (HEC) and forward (FCAL) calorimeters. The different parts of the LAr calorimeter have been installed inside the ATLAS cavern between October 2004 and April 2006. Since October 2006 the detector has been operated with liquid argon at nominal high voltage, and fully equipped with readout electronics including a LVL1 calorimeter trigger system. First cosmic runs were recorded and used in various stages of commissioning. Starting in September 2008 beam related events were collected for the first time with single beams circulating in the LHC ring providing first beam-gas interactions and then beam-collimator splash events. The fir...

The ATLAS trigger: high-level trigger commissioning and operation during early data taking

International Nuclear Information System (INIS)

Goncalo, R

2008-01-01

The ATLAS experiment is one of the two general-purpose experiments due to start operation soon at the Large Hadron Collider (LHC). The LHC will collide protons at a centre of mass energy of 14 TeV, with a bunch-crossing rate of 40 MHz. The ATLAS three-level trigger will reduce this input rate to match the foreseen offline storage capability of 100-200 Hz. This paper gives an overview of the ATLAS High Level Trigger focusing on the system design and its innovative features. We then present the ATLAS trigger strategy for the initial phase of LHC exploitation. Finally, we report on the valuable experience acquired through in-situ commissioning of the system where simulated events were used to exercise the trigger chain. In particular we show critical quantities such as event processing times, measured in a large-scale HLT farm using a complex trigger menu

Sim@P1: Using Cloudscheduler for offline processing on the ATLAS HLT farm

CERN Document Server

Berghaus, Frank; The ATLAS collaboration

2018-01-01

The Simulation at Point1 (Sim@P1) project was built in 2013 to take advantage of the ATLAS Trigger and Data Acquisition High Level Trigger (HLT) farm. The HLT farm provides more than 2,000 compute nodes, which are critical to ATLAS during data taking. When ATLAS is not recording data, this large compute resource is used to generate and process simulation data for the experiment. The Sim@P1 system uses virtual machines, deployed by OpenStack, in order to isolate the resources from the ATLAS technical and control network. During the upcoming long shutdown in 2019 (LS2), the HLT farm including the Sim@P1 infrastructure will be upgraded. A previous paper on the project emphasized the need for “simple, reliable, and efficient tools” to quickly switch between data acquisition operation and offline processing.In this contribution we assess various options for updating and simplifying the provisional tools. Cloudscheduler is a tool for provisioning cloud resources for batch computing that has been managing cloud ...

Quench propagation and protection analysis of the ATLAS Toroids

OpenAIRE

Dudarev, A; Gavrilin, A V; ten Kate, H H J; Baynham, D Elwyn; Courthold, M J D; Lesmond, C

2000-01-01

The ATLAS superconducting magnet system consists of the Barrel Toroid, two End Cap Toroids and the Central Solenoid. However, the Toroids of eight coils each are magnetically separate systems to the Central Solenoid. The Toroids are electrically connected in series and energized by a single power supply. The quench protection system is based on the use of relatively small external dump resistances in combination with quench-heaters activated after a quench event detection to initiate the inte...

Frameworks to monitor and predict resource usage in the ATLAS High Level Trigger

CERN Document Server

Martin, Tim; The ATLAS collaboration

2016-01-01

The ATLAS High Level Trigger Farm consists of around 30,000 CPU cores which filter events at up to 100 kHz input rate. A costing framework is built into the high level trigger, this enables detailed monitoring of the system and allows for data-driven predictions to be made utilising specialist datasets. This talk will present an overview of how ATLAS collects in-situ monitoring data on both CPU usage and dataflow over the data-acquisition network during the trigger execution, and how these data are processed to yield both low level monitoring of individual selection-algorithms and high level data on the overall performance of the farm. For development and prediction purposes, ATLAS uses a special `Enhanced Bias' event selection. This mechanism will be explained along with how is used to profile expected resource usage and output event-rate of new physics selections, before they are executed on the actual high level trigger farm.

Barrelled locally convex spaces

CERN Document Server

Pérez Carreras, P

1987-01-01

This book is a systematic treatment of barrelled spaces, and of structures in which barrelledness conditions are significant. It is a fairly self-contained study of the structural theory of those spaces, concentrating on the basic phenomena in the theory, and presenting a variety of functional-analytic techniques.Beginning with some basic and important results in different branches of Analysis, the volume deals with Baire spaces, presents a variety of techniques, and gives the necessary definitions, exploring conditions on discs to ensure that they are absorbed by the barrels of the sp

Modeling two-phase flow in barrels of weapons with combined charges

Directory of Open Access Journals (Sweden)

Nebojša P. Hristov

2011-10-01

Full Text Available The processes occurring during the firing within barrels of weapons with combined charges are described aiming at the improvement of fire power of existing weapons and the design of new ones. The firing process simulation enables the optimization of gunpowders. The analysis of the obtained results helps in choosing the best combination of input-output parameters for the highest muzzle velocity possible while keeping powder gas maximum pressures inside the barrel at the lowest possible level.

The construction of the ATLAS semi-conductor tracker

International Nuclear Information System (INIS)

Jones, Tim

2006-01-01

The ATLAS (A Toroidal LHC ApparatuS) experiment at the Large Hadron Collider (LHC) at CERN has been designed to explore physics at the TeV energy scale and will be commissioned in 2007. In the innermost region of the experiment is a charged particle tracker, the Inner Detector of which the Semiconductor Tracker (SCT) is a major component. The SCT comprises a central barrel section enclosed by two endcaps (A and C). The construction of the major components of the ATLAS Semi-conductor tracker (SCT) is now nearing completion. Following a brief description of the design of the SCT, the logistics and organisation of the construction phase of the project are discussed. Central to the delivery of a high quality detector is the testing of large numbers of modules both during assembly and after they are mounted on their final support structures. The results of these tests for endcap C are presented showing that the electrical performance of the 988 modules to be installed in ATLAS is compatible with the specifications required

Consumer demand for green stormwater management technology in an urban setting: The case of Chicago rain barrels

Science.gov (United States)

Ando, Amy W.; Freitas, Luiz P. C.

2011-12-01

Hydrological disruption and water pollution from urbanization can be reduced if households in urban areas adopt decentralized storm water controls. We study a citywide municipal subsidized rain-barrel program in the third biggest city in the United States, Chicago, to explore what factors influence whether households purchase this sort of green storm water management technology in an urban setting. Specifically, we regress census-tract level data on the number of rain barrels adopted in different parts of the city on socioeconomic variables, data on local flood frequency, and features of the housing stock. We find that rain-barrel purchases are not correlated with local levels of flooding, even though city residents were told by program managers that rain barrels could alleviate local flooding. Instead, rain barrels are heavily concentrated in places with high-income attitudinally green populations. We do find more rain barrels were adopted in places close to rain-barrel distribution points and near sites of hydrological information campaigns; thus, policy makers might increase green-technology adoption in areas where they can do the most good by reducing transaction costs and providing education programs to those areas. Finally, our results indicate that owner occupancy is positively correlated with green-technology adoption. Low-rise rental housing may have inefficiently low levels of adoption, such that city managers might want to develop programs to encourage storm water management investments by landlords who do not live in their own properties.

Pixel electronics for the ATLAS experiment

International Nuclear Information System (INIS)

Fischer, P.

2001-01-01

The ATLAS experiment at LHC will use 3 barrel layers and 2x5 disks of silicon pixel detectors as the innermost elements of the semiconductor tracker. The basic building blocks are pixel modules with an active area of 16.4 mmx60.8 mm which include an n + on n-type silicon sensor and 16 VLSI front-end (FE) chips. Every FE chip contains a low power, high speed charge sensitive preamplifier, a fast discriminator, and a readout system which operates at the 40 MHz rate of LHC. The addresses of hit pixels (as well as a low resolution pulse height information) are stored on the FE chips until arrival of a level 1 trigger signal. Hits are then transferred to a module controller chip (MCC) which collects the data of all 16 FE chips, builds complete events and sends the data through two optical links to the data acquisition system. The MCC receives clock and data through an additional optical link and provides timing and configuration information for the FE chips. Two additional chips are used to amplify and decode the pin diode signal and to drive the VCSEL laser diodes of the optical links

Performance And Radiation Hardness Of The Atlas/sct Detector Module

CERN Document Server

Eklund, L

2003-01-01

The ATLAS experiment is a general purpose experiment being constructed at the Large Hadron Collider (LHC) at FERN, Geneva. ATLAS is designed to exploit the full physics potential of LHC, in particular to study topics concerning the Higgs mechanism, Super-symmetry and CP violation. The cross sections for the processes under study are extremely small, requiring very high luminosity colliding beams. The Semiconductor Tracker (SCT) is an essential part of the Inner Detector tracking system of ATLAS. The active elements of the SCT is 4088 detector modules, tiled on four barrel cylinders and eighteen endcap disks. As a consequence of the high luminosity, the detector modules will operate in a harsh radiation environment. This thesis describes work concerning radiation hardness, beam test performance and methods for production testing of detector modules. The radiation hardness studies have been focused on the electrical performance of the front-end ASIC and the detector module. The results have identified features ...

ATLAS's superconducting solenoid takes up position

CERN Multimedia

2004-01-01

The ATLAS superconducting solenoid was moved to its final destination on 16 January. It has taken up position opposite the ATLAS liquid argon barrel cryostat, which will house the electromagnetic calorimeter. All that remains to do now is to slide it into the insulation vacuum, this will be done in the next few weeks. Built by Toshiba, under responsibility of KEK in Japan, the central solenoid is 2.4 metres in diameter, 5.3 metres long and weighs 5.5 tonnes. "It will provide an axial magnetic field of 2 Tesla that will deflect particles inside the inner detector," as Roger Ruber, on-site project coordinator, explains. The inner detector, which consists of three sub-detectors, will be installed inside the solenoid later. The solenoid during one of the transport operations. Securely attached to the overhead travelling crane, the solenoid is situated in front of the opening to the liquid argon calorimeter, it will be inserted soon.

Upgrading the ATLAS barrel tracker for the super-LHC

International Nuclear Information System (INIS)

Bates, Richard L.

2009-01-01

It has been proposed to increase the luminosity of the large hadron collider (LHC) at CERN by an order of magnitude, with the upgraded machine dubbed super-LHC. The ATLAS experiment will require a new tracker for this high-luminosity operation due to radiation damage and event density. In order to cope with the order of magnitude increase in pile-up backgrounds at the higher luminosity, an all-silicon tracker is being designed. The new strip detector will use significantly shorter strips than the current silicon tracker in order to minimize the occupancy. As the increased luminosity will mean a corresponding increase in radiation dose, a new generation of extremely radiation-hard silicon detectors is required. An R and D program is underway to develop silicon sensors with sufficient radiation hardness. New front-end electronics and readout systems are being designed to cope with the higher data rates. The challenges facing the sensors and the cooling and mechanical support will be discussed. A possible tracker layout will be described.

The ATLAS ITk strip detector. Status of R&D

Energy Technology Data Exchange (ETDEWEB)

García Argos, Carlos, E-mail: carlos.garcia.argos@cern.ch

2017-02-11

While the LHC at CERN is ramping up luminosity after the discovery of the Higgs Boson in the ATLAS and CMS experiments in 2012, upgrades to the LHC and experiments are planned. The major upgrade is foreseen for 2024, with a roughly tenfold increase in luminosity, resulting in corresponding increases in particle rates and radiation doses. In ATLAS the entire Inner Detector will be replaced for Phase-II running with an all-silicon system. This paper concentrates on the strip part. Its layout foresees low-mass and modular yet highly integrated double-sided structures for the barrel and forward region. The design features conceptually simple modules made from electronic hybrids glued directly onto the silicon. Modules will then be assembled on both sides of large carbon-core structures with integrated cooling and electrical services.

Commissioning of the ATLAS High Level Trigger with single beam and cosmic rays

Energy Technology Data Exchange (ETDEWEB)

Di Mattia, A, E-mail: dimattia@mail.cern.c [Michigan State University - Department of Physics and Astronomy 3218 Biomedical Physical Science - East Lansing, MI 48824-2320 (United States)

2010-04-01

ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). The trigger system is responsible for making the online selection of interesting collision events. At the LHC design luminosity of 10{sup 34} cm{sup -2}s{sup -1} it will need to achieve a rejection factor of the order of 10{sup -7} against random proton-proton interactions, while selecting with high efficiency events that are needed for physics analyses. After a first processing level using custom electronics based on FPGAs and ASICs, the trigger selection is made by software running on two processor farms, containing a total of around two thousand multi-core machines. This system is known as the High Level Trigger (HLT). To reduce the network data traffic and the processing time to manageable levels, the HLT uses seeded, step-wise reconstruction, aiming at the earliest possible rejection of background events. The recent LHC startup and short single-beam run provided a 'stress test' of the system and some initial calibration data. Following this period, ATLAS continued to collect cosmic-ray events for detector alignment and calibration purposes. After giving an overview of the trigger design and its innovative features, this paper focuses on the experience gained from operating the ATLAS trigger with single LHC beams and cosmic-rays.

First Cryogenic Testing of the ATLAS Superconducting Prototype Magnets

CERN Document Server

Delruelle, N; Haug, F; Mayri, C; Orlic, J P; Passardi, Giorgio; Pirotte, O; ten Kate, H H J

2002-01-01

The superconducting magnet system of the ATLAS detector will consist of a central solenoid, two end-cap toroids and the barrel toroid made of eight coils (BT) symmetrically placed around the central axis of the detector. All these magnets will be individually tested in an experimental area prior to their final installation in the underground cavern of the LHC collider. A dedicated cryogenic test facility has been designed and built for this purpose. It mainly consists of a 1'200 W at 4.5 K refrigerator, a 10 kW liquid nitrogen pre-cooling unit, a cryostat housing liquid helium centrifugal pumps, a distribution valve box and transfer lines. Prior to the start of the series tests of the BT magnets, two model coils are used at this facility. The first one, the so-called B00 of comparatively small size, contains the three different types of superconductors used for the ATLAS magnets which are wound on a cylindrical mandrel. The second magnet, the B0, is a reduced model of basically identical design concept as the...

Core barrel motion calibration factor calculation

International Nuclear Information System (INIS)

Shahrokhi, F.; Robinson, J.C.

1976-01-01

Neutron transport theory calculations were performed to obtain a calibration factor for inferring core-barrel motion from spectral density data using excore ionization chambers in PWRs. The analysis of core-barrel movement was based on the postulate that the movement is a cantilevered type, with the preferred direction x-x'

Discrete event simulation of the ATLAS second level trigger

International Nuclear Information System (INIS)

Vermeulen, J.C.; Dankers, R.J.; Hunt, S.; Harris, F.; Hortnagl, C.; Erasov, A.; Bogaerts, A.

1998-01-01

Discrete event simulation is applied for determining the computing and networking resources needed for the ATLAS second level trigger. This paper discusses the techniques used and some of the results obtained so far for well defined laboratory configurations and for the full system

Performance of the ATLAS Calorimeter Trigger in the LHC Run 1 Data Taking Period

CERN Document Server

Oliveira Damazio, D; The ATLAS collaboration

2013-01-01

The ATLAS detector operated very successfully at the LHC Run 1 data taking period collecting a large number of events used for the discovery of the Higgs boson as well as for the search for beyond the Standard Model physics. In the main search channels related to the finding of the Higgs, the ATLAS calorimeter system played a major role measuring the energy of photons, electrons, jets, taus and neutrinos, via missing transverse energy measurement. The ATLAS trigger system selects from the huge amount of events produced every second, those few that must be recorded for physics analysis (less than one out of 40 thousand can be kept). The selection process is performed in 3 levels with increasing complexity and resolution. The first level is hardware based, seeding the two other software levels called together the High-Level Trigger. The paper will describe details of the calorimeter based HLT algorithms with special emphasis on the algorithms used for missing transverse energy and jet detection which were impro...

End of the EM Barrel Presampler Construction and Insertion

CERN Multimedia

Hostachy, J.Y.

The liquid argon barrel presampler is a thin detector placed in front of the electromagnetic barrel calorimeter, made up of two half barrels also, but with 32 sectors per half barrel instead of 16. Each of these 64 sectors is 3.1 m long, 28 cm large and 2.9 cm thick. Three countries took part in its construction: France (LPSC-Grenoble), Sweden (KTH-Stockholm) and Morocco (Hassan II Ain Chock-Casablanca and Mohamed V-Rabat universities, and CNESTEN-Rabat). The design of the presampler started 11 years ago and the series production began at the end of 2000. Cabling, mechanical and electronic tests of the anodes were achieved in Morocco. Forty-one sectors were assembled and validated at the LPSC-Grenoble and 25 at the KTH-Stockholm. In November 2002, the first half was inserted on the inner face of the first EM calorimeter wheel. The insertion of the other 32 sectors in the second EM calorimeter wheel was achieved in July 2003 (see pictures). The production of two additional sectors will allow us to study the p...

Photon reconstruction in the ATLAS inner detector and liquid argon barrel calorimeter at the 2004 combined test beam

NARCIS (Netherlands)

Abat, E.; et al., [Unknown; Ferrari, P.; Gorfine, G.; Liebig, W.

2011-01-01

The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal

Instrumentation of a Level-1 Track Trigger in the ATLAS detector for the High Luminosity LHC

CERN Document Server

Boisvert, V; The ATLAS collaboration

2012-01-01

One of the main challenges in particle physics experiments at hadron colliders is to build detector systems that can take advantage of the future luminosity increase that will take place during the next decade. More than 200 simultaneous collisions will be recorded in a single event which will make the task to extract the interesting physics signatures harder than ever before. Not all events can be recorded hence a fast trigger system is required to select events that will be stored for further analysis. In the ATLAS experiment at the Large Hadron Collider (LHC) two different architectures for accommodating a level-1 track trigger are being investigated. The tracker has more readout channels than can be readout in time for the trigger decision. Both architectures aim for a data reduction of 10-100 in order to make readout of data possible in time for a level-1 trigger decision. In the first architecture the data reduction is achieved by reading out only parts of the detector seeded by a high rate pre-trigger ...

The PANDA Barrel DIRC detector

International Nuclear Information System (INIS)

Hoek, M.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Hohler, R.; Kalicy, G.; Kumawat, H.; Lehmann, D.; Lewandowski, B.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Zühlsdorf, M.; Dodokhov, V. Kh.; Britting, A.; Eyrich, W.

2014-01-01

The PANDA experiment at the new Facility for Antiproton and Ion Research in Europe (FAIR) at GSI, Darmstadt, will study fundamental questions of hadron physics and QCD using high-intensity cooled antiproton beams with momenta between 1.5 and 15 GeV/c. Efficient Particle Identification for a wide momentum range and the full solid angle is required for reconstructing the various physics channels of the PANDA program. Hadronic Particle Identification in the barrel region of the detector will be provided by a DIRC counter. The design is based on the successful BABAR DIRC with important improvements, such as focusing optics and fast photon timing. Several of these improvements, including different radiator geometries and optics, were tested in particle beams at GSI and at CERN. The evolution of the conceptual design of the PANDA Barrel DIRC and the performance of complex prototypes in test beam campaigns will be discussed

The PANDA Barrel DIRC detector

Energy Technology Data Exchange (ETDEWEB)

Hoek, M., E-mail: matthias.hoek@uni-mainz.de [Institut für Kernphysik, Johannes Gutenberg University Mainz, Mainz (Germany); Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Hohler, R.; Kalicy, G.; Kumawat, H.; Lehmann, D.; Lewandowski, B.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Zühlsdorf, M. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Dodokhov, V. Kh. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Britting, A.; Eyrich, W. [Friedrich Alexander-University of Erlangen-Nuremberg, Erlangen (Germany); and others

2014-12-01

The PANDA experiment at the new Facility for Antiproton and Ion Research in Europe (FAIR) at GSI, Darmstadt, will study fundamental questions of hadron physics and QCD using high-intensity cooled antiproton beams with momenta between 1.5 and 15 GeV/c. Efficient Particle Identification for a wide momentum range and the full solid angle is required for reconstructing the various physics channels of the PANDA program. Hadronic Particle Identification in the barrel region of the detector will be provided by a DIRC counter. The design is based on the successful BABAR DIRC with important improvements, such as focusing optics and fast photon timing. Several of these improvements, including different radiator geometries and optics, were tested in particle beams at GSI and at CERN. The evolution of the conceptual design of the PANDA Barrel DIRC and the performance of complex prototypes in test beam campaigns will be discussed.

Feedforward motor information enhances somatosensory responses and sharpens angular tuning of rat S1 barrel cortex neurons.

Science.gov (United States)

Khateb, Mohamed; Schiller, Jackie; Schiller, Yitzhak

2017-01-06

The primary vibrissae motor cortex (vM1) is responsible for generating whisking movements. In parallel, vM1 also sends information directly to the sensory barrel cortex (vS1). In this study, we investigated the effects of vM1 activation on processing of vibrissae sensory information in vS1 of the rat. To dissociate the vibrissae sensory-motor loop, we optogenetically activated vM1 and independently passively stimulated principal vibrissae. Optogenetic activation of vM1 supra-linearly amplified the response of vS1 neurons to passive vibrissa stimulation in all cortical layers measured. Maximal amplification occurred when onset of vM1 optogenetic activation preceded vibrissa stimulation by 20 ms. In addition to amplification, vM1 activation also sharpened angular tuning of vS1 neurons in all cortical layers measured. Our findings indicated that in addition to output motor signals, vM1 also sends preparatory signals to vS1 that serve to amplify and sharpen the response of neurons in the barrel cortex to incoming sensory input signals.

Test Specification of A1-1 Test for OECD-ATLAS Project

International Nuclear Information System (INIS)

Kang, Kyoung-Ho; Moon, Sang-Ki; Lee, Seung-Wook; Choi, Ki-Yong; Song, Chul-Hwa

2014-01-01

In the OECD-ATLAS project, design extension conditions (DECs) such as a station blackout (SBO) and a total loss of feed water (TLOFW) will be experimentally investigated to meet the international interests in the multiple high-risk DECs raised after the Fukushima accident. The proposed test matrix for the OECD-ATLAS project is summarized in Table 1.. In this study, detailed specification of the first test named as A1-1 in the OECD-ATLAS project was described. The target scenario of the A1-1 test is a prolonged SBO with delayed supply of turbine-driven auxiliary feedwater to only SG number 2 (SG-2). A SBO is one of the most important DECs in that without any proper operator actions, a total loss of heat sink leads to core uncover, to core damage, and ultimately a core melt-down scenario under high pressure. Due to this safety importance, a SBO is considered to be a base test item of the OECD-ATLAS project. A detailed specification of the first test named as A1-1 in the OECD-ATLAS project was described. The target scenario of the A1-1 test is a prolonged SBO with delayed supply of turbine-driven auxiliary feedwater to only SG-2 in order to consider an accident mitigation measure. The pre-test analysis using MARS code was performed with an aim of setting up the detailed test procedures for A1-1 test and also gaining the physical insights for a prolonged SBO transient. In the A1-1 test, a prolonged SBO transient will be simulated with two temporal phases: Phase (I) for conservative SBO transient without supply of turbine-driven auxiliary feedwater and Phase (II) for asymmetric cooling via single trained supply of turbine-driven auxiliary feedwater

Barrel calorimeter of the CMD-3 detector

Energy Technology Data Exchange (ETDEWEB)

Shebalin, V. E., E-mail: V.E.Shebalin@inp.nsk.su; Anisenkov, A. V.; Aulchenko, V. M.; Bashtovoy, N. S. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation); Epifanov, D. A. [University of Tokyo, Department of Physics (Japan); Epshteyn, L. B.; Grebenuk, A. A.; Ignatov, F. V.; Erofeev, A. L.; Kovalenko, O. A.; Kozyrev, A. N.; Kuzmin, A. S.; Logashenko, I. B.; Mikhailov, K. Yu.; Razuvaev, G. P.; Ruban, A. A.; Shwartz, B. A.; Talyshev, A. A.; Titov, V. M.; Yudin, Yu. V. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation)

2015-12-15

The structure of the barrel calorimeter of the CMD-3 detector is presented in this work. The procedure of energy calibration of the calorimeter and the method of photon energy restoration are described. The distinctive feature of this barrel calorimeter is its combined structure; it is composed of two coaxial subsystems: a liquid xenon calorimeter and a crystalline CsI calorimeter. The calorimeter spatial resolution of the photon conversion point is about 2 mm, which corresponds to an angular resolution of ∼6 mrad. The energy resolution of the calorimeter is about 8% for photons with energy of 200 MeV and 4% for photons with energy of 1 GeV.

Barrel calorimeter of the CMD-3 detector

International Nuclear Information System (INIS)

Shebalin, V. E.; Anisenkov, A. V.; Aulchenko, V. M.; Bashtovoy, N. S.; Epifanov, D. A.; Epshteyn, L. B.; Grebenuk, A. A.; Ignatov, F. V.; Erofeev, A. L.; Kovalenko, O. A.; Kozyrev, A. N.; Kuzmin, A. S.; Logashenko, I. B.; Mikhailov, K. Yu.; Razuvaev, G. P.; Ruban, A. A.; Shwartz, B. A.; Talyshev, A. A.; Titov, V. M.; Yudin, Yu. V.

2015-01-01

The structure of the barrel calorimeter of the CMD-3 detector is presented in this work. The procedure of energy calibration of the calorimeter and the method of photon energy restoration are described. The distinctive feature of this barrel calorimeter is its combined structure; it is composed of two coaxial subsystems: a liquid xenon calorimeter and a crystalline CsI calorimeter. The calorimeter spatial resolution of the photon conversion point is about 2 mm, which corresponds to an angular resolution of ∼6 mrad. The energy resolution of the calorimeter is about 8% for photons with energy of 200 MeV and 4% for photons with energy of 1 GeV

Characterisation of strip silicon detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam

CERN Document Server

INSPIRE-00407830; Blue, Andrew; Bates, Richard; Bloch, Ingo; Diez, Sergio; Fernandez-Tejero, Javier; Fleta, Celeste; Gallop, Bruce; Greenall, Ashley; Gregor, Ingrid-Maria; Hara, Kazuhiko; Ikegami, Yoichi; Lacasta, Carlos; Lohwasser, Kristin; Maneuski, Dzmitry; Nagorski, Sebastian; Pape, Ian; Phillips, Peter W.; Sperlich, Dennis; Sawhney, Kawal; Soldevila, Urmila; Ullan, Miguel; Unno, Yoshinobu; Warren, Matt

2016-07-29

The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity, totalling 1x10^35 cm^-2 s^-1 after 10 years of operation. A consequence of this increased luminosity is the expected radiation damage at 3000 fb^-1, requiring the tracking detectors to withstand hadron equivalences to over 1x10^16 1 MeV neutrons per cm^2. With the addition of increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 micron FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 micron thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 micron thick full size radial (Endcap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout...

Full supersymmetry simulation for ATLAS in DC1

International Nuclear Information System (INIS)

Biglietti, Michela; Brochu, Frederic; Costanzo, Davide; De, Kaushik; Duchovni, Ehud; Gupta, Ambreesh; Hinchliffe, Ian; Lester, Chris; Lipniacka, Anna; Loch, Peter; Lytken, Else; Ma, Hong; Nielsen, Jakob L.; Paige, Frank; Polesello, Giacomo; Rajagopalan, Srini; Schrager, Dan; Stavropoulos, Georgios; Tovey, Dan; Wielers, Monika

2004-01-01

This note reports results from a simulation of 100k events for one example of a minimal SUGRA supersymmetry case at the LHC using full simulation of the ATLAS detector. It was carried out as part ATLAS Data Challenge 1

Experimental Results of A1.2 Test for OECD-ATLAS Project

Energy Technology Data Exchange (ETDEWEB)

Kang, Kyoung-Ho; Bae, Byoung-Uhn; Park, Yu-Sun; Kim, Jong-Rok; Choi, Nam-Hyun; Choi, Ki-Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

In order to meet the international interests in the multiple high-risk design extension conditions (DECs) raised after the Fukushima accident, KAERI (Korea Atomic Energy Research Institute) is operating an OECD/NEA project (hereafter, OECD-ATLAS project) by utilizing a thermal-hydraulic integral effect test facility, ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation). As for a prolonged SBO transient of the OECD-ATLAS project, two tests, named A1.1 and A1.2, were determined to be performed. In particular, passive safety systems are considered as the most promising alternatives to reinforce the safety and reliability of an ultimate heat removal system without any operator actions in the SBO transients. As one of the new safety improvement concepts to mitigate an SBO accident efficiently, a cooling and operational performance of the passive auxiliary feedwater system (PAFS) is investigated in the framework of the OECD-ATLAS project to produce clearer knowledge of the actual phenomena and to provide the best guidelines for accident management. As the second test of the OECD-ATLAS project, the A1.2 test was conducted to simulate a prolonged SBO with asymmetric secondary cooling through the supply of passive auxiliary feedwater only to SG-2. When the collapsed water level of steam generator reached a wide range of 25%, PAFS was actuated. PAFS played a key role in cooling down the primary system by the heat transfer and the natural circulation. With the actuation of PAFS, the fluid temperatures at the core inlet and outlet started to decrease without any excursion of the maximum heater surface temperature in the core. This integral effect test data of A1.2 test can be used to evaluate the prediction capability of existing safety analysis codes and identify any code deficiency for an SBO simulation with an operation of a passive system such as PAFS.

Plasticity-Related Gene 1 Affects Mouse Barrel Cortex Function via Strengthening of Glutamatergic Thalamocortical Transmission

OpenAIRE

Unichenko, Petr; Kirischuk, Sergei; Yang, Jenq-Wei; Baumgart, Jan; Roskoden, Thomas; Schneider, Patrick; Sommer, Angela; Horta, Guilherme; Radyushkin, Konstantin; Nitsch, Robert; Vogt, Johannes; Luhmann, Heiko J.

2016-01-01

Plasticity-related gene-1 (PRG-1) is a brain-specific protein that modulates glutamatergic synaptic transmission. Here we investigated the functional role of PRG-1 in adolescent and adult mouse barrel cortex both in vitro and in vivo. Compared with wild-type (WT) animals, PRG-1-deficient (KO) mice showed specific behavioral deficits in tests assessing sensorimotor integration and whisker-based sensory discrimination as shown in the beam balance/walking test and sandpaper tactile discriminatio...

Combined performance studies for electrons at the 2004 ATLAS combined test-beam

International Nuclear Information System (INIS)

Abat, E; Arik, E; Abdallah, J M; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Anghinolfi, F; Baron, S; Alexa, C; Anderson, K; Andreazza, A; Banfi, D; Antonaki, A; Arabidze, G; Atkinson, T; Baines, J; Baker, O K

2010-01-01

In 2004 at the ATLAS (A Toroidal LHC ApparatuS) combined test beam, one slice of the ATLAS barrel detector (including an Inner Detector set-up and the Liquid Argon calorimeter) was exposed to particles from the H8 SPS beam line at CERN. It was the first occasion to test the combined electron performance of ATLAS. This paper presents results obtained for the momentum measurement p with the Inner Detector and for the performance of the electron measurement with the LAr calorimeter (energy E linearity and resolution) in the presence of a magnetic field in the Inner Detector for momenta ranging from 20 GeV/c to 100 GeV/c. Furthermore the particle identification capabilities of the Transition Radiation Tracker, Bremsstrahlungs-recovery algorithms relying on the LAr calorimeter and results obtained for the E/p ratio and a way how to extract scale parameters will be discussed.

Combined performance studies for electrons at the 2004 ATLAS combined test-beam

Energy Technology Data Exchange (ETDEWEB)

Abat, E; Arik, E [Bogazici University, Faculty of Sciences, Department of Physics, TR - 80815 Bebek-Istanbul (Turkey); Abdallah, J M [Institut de Fisica d' Altes Energies, IFAE, Universitat Autonoma de Barcelona, Edifici Cn, ES - 08193 Bellaterra, Barcelona Spain (Spain); Addy, T N [Hampton University, Department of Physics, Hampton, VA 23668 (United States); Adragna, P [Queen Mary, University of London, Mile End Road, E1 4NS, London (United Kingdom); Aharrouche, M [Universitaet Mainz, Institut fuer Physik, Staudinger Weg 7, DE 55099 (Germany); Ahmad, A [Insitute of Physics, Academia Sinica, TW - Taipei 11529, Taiwan (China); Akesson, T P A [Lunds universitet, Naturvetenskapliga fakulteten, Fysiska institutionen, Box 118, SE - 221 00, Lund (Sweden); Aleksa, M; Anghinolfi, F; Baron, S [European Laboratory for Particle Physics (CERN), CH-1211 Geneva 23 (Switzerland); Alexa, C [National Institute of Physics and Nuclear Engineering (Bucharest -IFIN-HH), P.O. Box MG-6, R-077125 Bucharest (Romania); Anderson, K [University of Chicago, Enrico Fermi Institute, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Andreazza, A; Banfi, D [INFN Sezione di Milano, via Celoria 16, IT - 20133 Milano (Italy); Antonaki, A; Arabidze, G [University of Athens, Nuclear and Particle Physics Department of Physics, Panepistimiopouli Zografou, GR 15771 Athens (Greece); Atkinson, T [School of Physics, University of Melbourne, AU - Parkvill, Victoria 3010 (Australia); Baines, J [Rutherford Appleton Laboratory, Science and Technology Facilities Council, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Baker, O K, E-mail: robert.froeschl@cern.c [Yale University, Department of Physics, PO Box 208121, New Haven, CT06520-8121 (United States)

2010-11-15

In 2004 at the ATLAS (A Toroidal LHC ApparatuS) combined test beam, one slice of the ATLAS barrel detector (including an Inner Detector set-up and the Liquid Argon calorimeter) was exposed to particles from the H8 SPS beam line at CERN. It was the first occasion to test the combined electron performance of ATLAS. This paper presents results obtained for the momentum measurement p with the Inner Detector and for the performance of the electron measurement with the LAr calorimeter (energy E linearity and resolution) in the presence of a magnetic field in the Inner Detector for momenta ranging from 20 GeV/c to 100 GeV/c. Furthermore the particle identification capabilities of the Transition Radiation Tracker, Bremsstrahlungs-recovery algorithms relying on the LAr calorimeter and results obtained for the E/p ratio and a way how to extract scale parameters will be discussed.

Results of 3D photogrammetry on the CMS barrel yoke

International Nuclear Information System (INIS)

Goudard, R.; Humbertclaude, C.; Nummiaro, K.

1999-01-01

The CMS (Compact Muon Solenoid) detector of the new LHC will be built till 2005 at CERN in Geneva. The Barrel Yoke survey has been decided to be done mostly by photogrammetry. After this first measurement, it has been proved that a practical simulation and a study of adapted tools and procedures were helpful for measurement on such a large object. Using only conventional surveying methods would have been impossible with such constraints. The most important points were the high required accuracy compared to the size of the object, the connection of the two planes, the time intervention, the restricted factory environment and the impossibility for having any outside network. The photogrammetric method was considered to be the best way to survey the Barrel Yoke ring. Since the required precision has been reached at all levels with the first full Barrel measurements, the procedure is validated for the four remaining Barrels in the factory and afterwards again at CERN. This project was challenging due to the size of the object, the required accuracy and the lack of practical references in the field of digital industrial photogrammetry. This method is a new step for using the three dimensional photogrammetric measurements on large objects. (authors)

Modules and Front-End Electronics Developments for the ATLAS ITk Strips Upgrade

CERN Document Server

Garcia-Argos, Carlos; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High Luminosity LHC, scheduled for 2024. The existing Inner Detector will be replaced by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The ITk strip detector consists of a four layer barrel and a forward region composed of six discs on each side of the barrel. The basic unit of the detector is the silicon-strip module, consisting of a sensor and one or more hybrid circuits that hold the read-out electronics. The geometries of the barrel and end-cap modules take into account the regions that they have to cover. In the central region, the detectors are rectangular with straight strips, whereas on the forward region the modules require wedge shaped sensors with varying strip length and pitch. The current prototyping phase has resulted in the ITk Strip Detector Technical Design Report (TDR), which kicks-off the pre-production readiness phase at the involved institutes. ...

Modules and Front-End Electronics Developments for the ATLAS ITk Strips Upgrade

CERN Document Server

Garcia-Argos, Carlos; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High Luminosity LHC, scheduled for 2024. The existing Inner Detector will be replaced by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The ITk strip detector consists of a four layer barrel and a forward region composed of six discs on each side of the barrel. The basic unit of the detector is the silicon-strip module, consisting of a sensor and one or more hybrid circuits that hold the read-out electronics. The geometries of the barrel and end-cap modules take into account the regions that they have to cover. In the central region, the detectors are rectangular with straight strips, whereas in the forward region the modules require wedge shaped sensors with varying strip length and pitch. The current prototyping phase has resulted in the ITk Strip Detector Technical Design Report (TDR), which kicks-off the pre-production readiness phase at the involved institutes. ...

The Level-1 Calorimeter Global Feature Extractor (gFEX) Boosted Object Trigger for the Phase-I Upgrade of the ATLAS Experiment

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00235957; The ATLAS collaboration; Stark, Giordon; Miller, David

2016-01-01

The Global Feature Extractor (gFEX) module is a planned component of the Level 1 online trigger system for the ATLAS experiment planned for installation during the Phase I upgrade in 2018. This unique single electronics board with multiple high speed processors will receive coarse-granularity information from all the ATLAS calorimeters enabling the identification in real time of large-radius jets for capturing Lorentz-boosted objects such as top quarks, Higgs, $Z$ and $W$ bosons. The gFEX architecture also facilitates the calculation of global event variables such as missing transverse energy, centrality for heavy ion collisions, and event-by-event pile-up energy density. Details of the electronics architecture that provides these capabilities are presented, along with results of tests of the prototype systems now available. The status of the firmware algorithm design and implementation as well as monitoring capabilities are also presented.

Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam

Czech Academy of Sciences Publication Activity Database

Abat, E.; Abdallah, J.M.; Addy, T.N.; Lokajíček, Miloš; Němeček, Stanislav

2010-01-01

Roč. 6, č. 4 (2010), P04001/1-P04001/32 ISSN 1748-0221 R&D Projects: GA MŠk LA08047 Institutional research plan: CEZ:AV0Z10100502 Keywords : ATLAS * calorimeter * tracking detector * photon * Monte Carlo Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 3.148, year: 2010

Design, Results, Evolution and Status of the ATLAS Simulation at Point1 Project

CERN Document Server

AUTHOR|(SzGeCERN)377840; Fressard-Batraneanu, Silvia Maria; Ballestrero, Sergio; Contescu, Alexandru Cristian; Fazio, Daniel; Di Girolamo, Alessandro; Lee, Christopher Jon; Pozo Astigarraga, Mikel Eukeni; Scannicchio, Diana; Sedov, Alexey; Twomey, Matthew Shaun; Wang, Fuquan; Zaytsev, Alexander

2015-01-01

Abstract. During the LHC Long Shutdown 1 period (LS1), that started in 2013, the Simulation at Point1 (Sim@P1) Project takes advantage, in an opportunistic way, of the TDAQ (Trigger and Data Acquisition) HLT (High Level Trigger) farm of the ATLAS experiment. This farm provides more than 1300 compute nodes, which are particularly suited for running event generation and Monte Carlo production jobs that are mostly CPU and not I/O bound. It is capable of running up to 2700 virtual machines (VMs) provided with 8 CPU cores each, for a total of up to 22000 parallel running jobs. This contribution gives a review of the design, the results, and the evolution of the Sim@P1 Project; operating a large scale OpenStack based virtualized platform deployed on top of the ATLAS TDAQ HLT farm computing resources. During LS1, Sim@P1 was one of the most productive ATLAS sites: it delivered more than 50 million CPU-hours and it generated more than 1.7 billion Monte Carlo events to various analysis communities. The design aspects a...

ATLAS SCT - Progress on the Silicon Modules

CERN Multimedia

Tyndel, M.

The ATLAS SCT consists of 4088 silicon modules. Each module is made up of 4 silicon sensors with 1536 readout strips. Individual strips are connected to FE amplifiers, discriminators and pipelines on the module, i.e. there are 12 radiation hard ASICs, each containing 128 channels on the module. The sensors and the ASICs were developed for the ATLAS experiment and production is proceeding smoothly with over half the components delivered. The components of a module - 4 silicon sensors, a Cu/polyimide hybrid and pitch adaptor, and 12 ASICs - need to be carefully and precisely assembled onto a carbon and ceramic framework, which supports the module and removes the heat. Eleven production clusters are preparing to carry this out over the next two years. An important milestone for the barrel modules has been passed with the first cluster (KEK) now in production (~40 modules produced). A second cluster UK-B has qualified by producing five modules within specification (see below) and is about to start production. T...

Production Performance of the ATLAS Semiconductor Tracker Readout System

CERN Document Server

Mitsou, V A

2006-01-01

The ATLAS Semiconductor Tracker (SCT) together with the pixel and the transition radiation detectors will form the tracking system of the ATLAS experiment at LHC. It will consist of 20000 single-sided silicon microstrip sensors assembled back-to-back into modules mounted on four concentric barrels and two end-cap detectors formed by nine disks each. The SCT module production and testing has finished while the macro-assembly is well under way. After an overview of the layout and the operating environment of the SCT, a description of the readout electronics design and operation requirements will be given. The quality control procedure and the DAQ software for assuring the electrical functionality of hybrids and modules will be discussed. The focus will be on the electrical performance results obtained during the assembly and testing of the end-cap SCT modules.

STATUS OF THE ATLAS LIQUID ARGON CALORIMETER AND ITS PERFORMANCE

CERN Document Server

Berillari, T; The ATLAS collaboration

2011-01-01

The liquid argon (LAr) calorimeters are used in ATLAS for all electromagnetic and for hadron calorimetry. The LAr calorimeter system consists of an electromagnetic barrel calorimeter and two endcaps with electromagnetic, hadronic and forward calorimeters. The latest status of the detector as well as problems and solutions addressed during the last years will be presented. Aspects of operation of a large detector over a long time period will be summarized and selected topics showing the performance of the detector will be shown.

An FPGA based demonstrator for a topological processor in the future ATLAS L1-Calo trigger “GOLD”

CERN Document Server

Ebling, A; Büscher, V; Degele, R; Ji, W; Meyer, C; Moritz, S; Schäfer, U; Simioni, E; Tapprogge, S; Wenzel, V

2012-01-01

Abstract: The existing ATLAS trigger consists of three levels. The level 1 (L1) is an FPGAs based custom designed trigger, while the second and third levels are software based. The LHC machine plans to bring the beam energy to the maximum value of 7 TeV and to increase the luminosity in the coming years. The current L1 trigger system is therefore seriously challenged. To cope with the resulting higher event rate, as part of the ATLAS trigger upgrade, a new electronics module is foreseen to be added in the ATLAS Level-1 Calorimeter Trigger electronics chain: the Topological Processor (TP). Such a processor needs fast optical I/O and large aggregate bandwidth to use the information on trigger object position in space (e.g. jets in the calorimeters or muons measured in the muon detectors) to improve the purity of the L1 triggers streams by applying topological cuts within the L1 latency budget. In this paper, an overview of the adopted technological solutions and the R&D activities on the demonstrator for th...

Design, Results, Evolution and Status of the ATLAS Simulation at Point1 Project

Science.gov (United States)

Ballestrero, S.; Batraneanu, S. M.; Brasolin, F.; Contescu, C.; Fazio, D.; Di Girolamo, A.; Lee, C. J.; Pozo Astigarraga, M. E.; Scannicchio, D. A.; Sedov, A.; Twomey, M. S.; Wang, F.; Zaytsev, A.

2015-12-01

During the LHC Long Shutdown 1 (LSI) period, that started in 2013, the Simulation at Point1 (Sim@P1) project takes advantage, in an opportunistic way, of the TDAQ (Trigger and Data Acquisition) HLT (High-Level Trigger) farm of the ATLAS experiment. This farm provides more than 1300 compute nodes, which are particularly suited for running event generation and Monte Carlo production jobs that are mostly CPU and not I/O bound. It is capable of running up to 2700 Virtual Machines (VMs) each with 8 CPU cores, for a total of up to 22000 parallel jobs. This contribution gives a review of the design, the results, and the evolution of the Sim@P1 project, operating a large scale OpenStack based virtualized platform deployed on top of the ATLAS TDAQ HLT farm computing resources. During LS1, Sim@P1 was one of the most productive ATLAS sites: it delivered more than 33 million CPU-hours and it generated more than 1.1 billion Monte Carlo events. The design aspects are presented: the virtualization platform exploited by Sim@P1 avoids interferences with TDAQ operations and it guarantees the security and the usability of the ATLAS private network. The cloud mechanism allows the separation of the needed support on both infrastructural (hardware, virtualization layer) and logical (Grid site support) levels. This paper focuses on the operational aspects of such a large system during the upcoming LHC Run 2 period: simple, reliable, and efficient tools are needed to quickly switch from Sim@P1 to TDAQ mode and back, to exploit the resources when they are not used for the data acquisition, even for short periods. The evolution of the central OpenStack infrastructure is described, as it was upgraded from Folsom to the Icehouse release, including the scalability issues addressed.

Resource utilization by the ATLAS High Level Trigger during 2010 and 2011 LHC running

CERN Document Server

Ospanov, R

2012-01-01

In 2010 and 2011, the ATLAS experiment successfully recorded data from LHC collisions with high efficiency and excellent data quality. ATLAS employs a three-level trigger system to select events of interest for physics analyses and detector commissioning. The trigger system consists of a custom-designed hardware trigger at level-1 and software algorithms at the two higher levels. The trigger selection is defined by a trigger menu which consists of more than 300 individual trigger signatures, such as electrons, muons, particle jets, etc. An execution of a trigger signature incurs computing and data storage costs. Th composition of the deployed trigger menu depends on the instantaneous LHC luminosity, the experiment's goals for the recorded data, and the limits imposed by the available computing power, network bandwidth and storage space. This paper describes a trigger monitoring framework for assigning computing costs for individual trigger signatures and trigger menus as a whole. These costs can be extrapolat...

The Phase-2 ATLAS ITk Pixel Upgrade

CERN Document Server

Flick, Tobias; The ATLAS collaboration

2016-01-01

The entire tracking system of the ATLAS experiment will be replaced during the LHC Phase II shutdown (foreseen to take place around 2025) by an all-silicon detector called the “ITk” (Inner Tracker). The pixel detector will comprise the five innermost layers, and will be instrumented with new sensor and readout electronics technologies to improve the tracking performance and cope with the HL-LHC environment, which will be severe in terms of occupancy and radiation. The total surface area of silicon in the new pixel system could measure up to 14 m2, depending on the final layout choice, which is expected to take place in early 2017. Four layout options are being investigated at the moment, two with forward coverage to |eta| < 3.2 and two to |eta| < 4. For each coverage option, a layout with long barrel staves and a layout with novel inclined support structures in the barrel-endcap overlap region are considered. All potential layouts include modules mounted on ring-shaped supports in the endcap regions...

ATLAS Silicon Microstrip Tracker Operation and Performance

CERN Document Server

Barone, G; The ATLAS collaboration

2013-01-01

The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). In the talk the current results from the successful operation of the SCT Detector at the LHC and its status after three years of operation will be presented. We will report on the operation of the detector including an overview of the issues we encountered and the observation of significant increases in leakage currents (as expected) from bulk damage due to non-ionising radiation. The main emphasis will be given to the tracking performance of the SCT and the data quality during the >2 ye...

The ATLAS semiconductor tracker: operations and performance

CERN Document Server

D'Auria, S; The ATLAS collaboration

2012-01-01

The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar {it p}-in-{it n} technology. The signals are processed in the front-end ASICS ABCD3TA, working in binary readout mode. Data is transferred to the off-detector readout electronics via optical fibres. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications. In the talk the current results from the successful operation of the SCT Detector at the LHC and its status af...

The ATLAS Semiconductor tracker: operations and performance

CERN Document Server

Pani, P; The ATLAS collaboration

2013-01-01

Tracker After more than 3 years of successful operation at the LHC, we report on the operation and performance of the Semi-Conductor Tracker (SCT) functioning in a high luminosity, high radiation environment. The SCT is part of the ATLAS experiment at CERN and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibers. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications; the alignment is very cl...

Performances of the ATLAS Hadronic Tile Calorimeter Modules for Electrons and Pions

CERN Document Server

Kulchitskii, Yu A

2004-01-01

With the aim of establishing of an electromagnetic energy scale of the ATLAS Tile calorimeter and understanding of performance of the calorimeter to electrons 12 \\% of modules have been exposed in electron beams with various energies by three possible ways: cell-scan at $\\theta =20^o$ at the centers of the front face cells, $\\eta$-scan and tilerow scan at $\\theta = 90^o$ for the module side cells. We have extracted the electron calibration constants and electron energy resolutions some of these barrel and extended barrel modules at energies E = 10, 20, 50, 100 and 180 GeV for the cell-scan at $\\theta = 20^o$, the $\\eta$ scan and the tile scan at $90^o$. The average values of these constants are equal to $\\langle R_e \\rangle =1.157\\pm0.002$ pC/GeV for the cell-scan at $\\theta = 20^o$, $\\langle R_e \\rangle =1.143\\pm0.005$ pC/GeV for the $\\eta$-scan and $\\langle R_e\\rangle =1.196\\pm0.005$ pC/GeV for the tile-scan at $\\theta = 90^o$. The RMS values are the following: for the cell-scan is $RMS=2.6\\pm0.1$ \\%, for t...

Frameworks to monitor and predict rates and resource usage in the ATLAS High Level Trigger

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00219969; The ATLAS collaboration

2017-01-01

The ATLAS High Level Trigger Farm consists of around 40,000 CPU cores which filter events at an input rate of up to 100 kHz. A costing framework is built into the high level trigger thus enabling detailed monitoring of the system and allowing for data-driven predictions to be made utilising specialist datasets. An overview is presented in to how ATLAS collects in-situ monitoring data on CPU usage during the trigger execution, and how these data are processed to yield both low level monitoring of individual selection-algorithms and high level data on the overall performance of the farm. For development and prediction purposes, ATLAS uses a special ‘Enhanced Bias’ event selection. This mechanism is explained along with how it is used to profile expected resource usage and output event rate of new physics selections, before they are executed on the actual high level trigger farm.

Hadron energy reconstruction for the ATLAS calorimetry in the framework of the nonparametrical method

CERN Document Server

Akhmadaliev, S Z; Ambrosini, G; Amorim, A; Anderson, K; Andrieux, M L; Aubert, Bernard; Augé, E; Badaud, F; Baisin, L; Barreiro, F; Battistoni, G; Bazan, A; Bazizi, K; Belymam, A; Benchekroun, D; Berglund, S R; Berset, J C; Blanchot, G; Bogush, A A; Bohm, C; Boldea, V; Bonivento, W; Bosman, M; Bouhemaid, N; Breton, D; Brette, P; Bromberg, C; Budagov, Yu A; Burdin, S V; Calôba, L P; Camarena, F; Camin, D V; Canton, B; Caprini, M; Carvalho, J; Casado, M P; Castillo, M V; Cavalli, D; Cavalli-Sforza, M; Cavasinni, V; Chadelas, R; Chalifour, M; Chekhtman, A; Chevalley, J L; Chirikov-Zorin, I E; Chlachidze, G; Citterio, M; Cleland, W E; Clément, C; Cobal, M; Cogswell, F; Colas, Jacques; Collot, J; Cologna, S; Constantinescu, S; Costa, G; Costanzo, D; Crouau, M; Daudon, F; David, J; David, M; Davidek, T; Dawson, J; De, K; de La Taille, C; Del Peso, J; Del Prete, T; de Saintignon, P; Di Girolamo, B; Dinkespiler, B; Dita, S; Dodd, J; Dolejsi, J; Dolezal, Z; Downing, R; Dugne, J J; Dzahini, D; Efthymiopoulos, I; Errede, D; Errede, S; Evans, H; Eynard, G; Fassi, F; Fassnacht, P; Ferrari, A; Ferrer, A; Flaminio, Vincenzo; Fournier, D; Fumagalli, G; Gallas, E; Gaspar, M; Giakoumopoulou, V; Gianotti, F; Gildemeister, O; Giokaris, N; Glagolev, V; Glebov, V Yu; Gomes, A; González, V; González de la Hoz, S; Grabskii, V; Graugès-Pous, E; Grenier, P; Hakopian, H H; Haney, M; Hébrard, C; Henriques, A; Hervás, L; Higón, E; Holmgren, Sven Olof; Hostachy, J Y; Hoummada, A; Huston, J; Imbault, D; Ivanyushenkov, Yu M; Jézéquel, S; Johansson, E K; Jon-And, K; Jones, R; Juste, A; Kakurin, S; Karyukhin, A N; Khokhlov, Yu A; Khubua, J I; Klioukhine, V I; Kolachev, G M; Kopikov, S V; Kostrikov, M E; Kozlov, V; Krivkova, P; Kukhtin, V V; Kulagin, M; Kulchitskii, Yu A; Kuzmin, M V; Labarga, L; Laborie, G; Lacour, D; Laforge, B; Lami, S; Lapin, V; Le Dortz, O; Lefebvre, M; Le Flour, T; Leitner, R; Leltchouk, M; Li, J; Liablin, M V; Linossier, O; Lissauer, D; Lobkowicz, F; Lokajícek, M; Lomakin, Yu F; López-Amengual, J M; Lund-Jensen, B; Maio, A; Makowiecki, D S; Malyukov, S N; Mandelli, L; Mansoulié, B; Mapelli, Livio P; Marin, C P; Marrocchesi, P S; Marroquim, F; Martin, P; Maslennikov, A L; Massol, N; Mataix, L; Mazzanti, M; Mazzoni, E; Merritt, F S; Michel, B; Miller, R; Minashvili, I A; Miralles, L; Mnatzakanian, E A; Monnier, E; Montarou, G; Mornacchi, Giuseppe; Moynot, M; Muanza, G S; Nayman, P; Némécek, S; Nessi, Marzio; Nicoleau, S; Niculescu, M; Noppe, J M; Onofre, A; Pallin, D; Pantea, D; Paoletti, R; Park, I C; Parrour, G; Parsons, J; Pereira, A; Perini, L; Perlas, J A; Perrodo, P; Pilcher, J E; Pinhão, J; Plothow-Besch, Hartmute; Poggioli, Luc; Poirot, S; Price, L; Protopopov, Yu; Proudfoot, J; Puzo, P; Radeka, V; Rahm, David Charles; Reinmuth, G; Renzoni, G; Rescia, S; Resconi, S; Richards, R; Richer, J P; Roda, C; Rodier, S; Roldán, J; Romance, J B; Romanov, V; Romero, P; Rossel, F; Rusakovitch, N A; Sala, P; Sanchis, E; Sanders, H; Santoni, C; Santos, J; Sauvage, D; Sauvage, G; Sawyer, L; Says, L P; Schaffer, A C; Schwemling, P; Schwindling, J; Seguin-Moreau, N; Seidl, W; Seixas, J M; Selldén, B; Seman, M; Semenov, A; Serin, L; Shaldaev, E; Shochet, M J; Sidorov, V; Silva, J; Simaitis, V J; Simion, S; Sissakian, A N; Snopkov, R; Söderqvist, J; Solodkov, A A; Soloviev, A; Soloviev, I V; Sonderegger, P; Soustruznik, K; Spanó, F; Spiwoks, R; Stanek, R; Starchenko, E A; Stavina, P; Stephens, R; Suk, M; Surkov, A; Sykora, I; Takai, H; Tang, F; Tardell, S; Tartarelli, F; Tas, P; Teiger, J; Thaler, J; Thion, J; Tikhonov, Yu A; Tisserant, S; Tokar, S; Topilin, N D; Trka, Z; Turcotte, M; Valkár, S; Varanda, M J; Vartapetian, A H; Vazeille, F; Vichou, I; Vinogradov, V; Vorozhtsov, S B; Vuillemin, V; White, A; Wielers, M; Wingerter-Seez, I; Wolters, H; Yamdagni, N; Yosef, C; Zaitsev, A; Zitoun, R; Zolnierowski, Y

2002-01-01

This paper discusses hadron energy reconstruction for the ATLAS barrel prototype combined calorimeter (consisting of a lead-liquid argon electromagnetic part and an iron-scintillator hadronic part) in the framework of the nonparametrical method. The nonparametrical method utilizes only the known e/h ratios and the electron calibration constants and does not require the determination of any parameters by a minimization technique. Thus, this technique lends itself to an easy use in a first level trigger. The reconstructed mean values of the hadron energies are within +or-1% of the true values and the fractional energy resolution is [(58+or-3)%/ square root E+(2.5+or-0.3)%](+)(1.7+or-0.2)/E. The value of the e/h ratio obtained for the electromagnetic compartment of the combined calorimeter is 1.74+or-0.04 and agrees with the prediction that e/h >1.66 for this electromagnetic calorimeter. Results of a study of the longitudinal hadronic shower development are also presented. The data have been taken in the H8 beam...

Short description of BMS/BMF MDT chamber production for the muon spectrometer of the ATLAS experiment

International Nuclear Information System (INIS)

Barashkov, A.V.; Glonti, G.L.; Gongadze, A.L.; Gongadze, I.B.; Gostkin, M.I.; Gus'kov, A.V.; Dedovich, D.V.; Demichev, M.A.; Evtukhovich, P.G.; Elagin, A.L.; Zhemchugov, A.S.; Il'yushenko, E.N.; Kotov, S.A.; Kotova, T.I.; Korolevich, Ya.V.; Kruchonok, V.G.; Krumshtejn, Z.V.; Kuznetsov, N.K.; Lomidze, D.D.; Nikolaev, K.V.; Potrap, I.N.; Rudenko, T.O.; Kharchenko, D.V.; Tskhadadze, Eh.G.; Chepurnov, V.F.; Shelkov, G.A.; Shiyakova, M.M.; Shcherbakov, A.A.; Podkladkin, S.Yu.

2005-01-01

The method of assembly of the MDT chambers for the muon spectrometer of the ATLAS experiment is described. During 2000-2004 ∼ 25000 drift tubes were produced at the DLNP, JINR. The tubes were assembled into 84 muon chambers of BMS/BMF type, one of the six main types for the barrel part of the ATLAS muon spectrometer. Particle momenta must be measured in the ATLAS spectrometer with very high precision (2% at 100 GeV/c and 10% at 1000 GeV/c), which required to produce the coordinate detectors with very high (∼80 μm) precision. We describe the method of assembly of large-scale 5-10 m 2 muon chambers with the signal wire mean deviation from the nominal position less than 20 μm

Study and analysis for the flow-induced vibration of the core barrel of a PWR

International Nuclear Information System (INIS)

Yao Weida; Shi Guolin; Jiang Nanyan

1989-01-01

The resemblance criteria are derived and a test model is designed by applying the flow-soild coupling theory. After having completed the model analysis of the pressurized water reactor (PWR) core barrel in an 1:10 model, the dynamic characteristics are obtained. In an 1:5 reactor model with a hydraulic closed loop, the hydraulic vibration tests of the core barrel are performed, and the relations between the flow rate and the flow-induced pulse pressure on core barrel, acceleration and strain signals have been measured. The corresponding responses and a group of computational equations for hydraulic vibration are derived from these two experiments. The computational hydraulic vibration responses for core barrel in Qinshan Nuclear Power Plant are in good agreement with the test results, and it shows that the core barrel is safe within its lifetime of 30 years

Sacral Theater, a code to simulate the propagation of the superconducting magnet LHC atlas barrel toroid transition

International Nuclear Information System (INIS)

Gastineau, B.

2000-06-01

Sacral Theater has been developed for the toroid magnet Atlas of the CERN LHC project. This three dimensional calculations code calculates the propagation of the transition of a superconducting coil in 25 m long hippodrome. Procedures to study low currents have been included. This work is a part of the magnet safety system because the coils protection is made by warmers activating the quench propagation in case of default detection. This allows the complete dissipation of storage energy that can reach 1080 MJ on Atlas. (N.C.)

Performance of the ATLAS first-level Trigger with first LHC Data

CERN Document Server

Lundberg, J; The ATLAS collaboration

2010-01-01

ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). Its trigger system must reduce the anticipated proton collision rate of up to 40 MHz to a recordable event rate of 100-200 Hz. This is realized through a multi-level trigger system. The first-level trigger is implemented with custom-built electronics and makes an initial selection which reduces the rate to less than 100 kHz. The subsequent trigger selection is done in software run on PC farms. The first-level trigger decision is made by the central-trigger processor using information from coarse grained calorimeter information, dedicated muon-trigger detectors, and a variety of additional trigger inputs from detectors in the forward regions. We present the performance of the first-level trigger during the commissioning of the ATLAS detector during early LHC running. We cover the trigger strategies used during the different machine commissioning phases from first circulating beams and splash events to collisions. It is descri...

The PANDA Barrel DIRC

Science.gov (United States)

Schwiening, J.; Ali, A.; Belias, A.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Kalicy, G.; Krebs, M.; Lehmann, D.; Nerling, F.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Traxler, M.; Böhm, M.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Düren, M.; Etzelmüller, E.; Föhl, K.; Hayrapetyan, A.; Kreutzfeld, K.; Merle, O.; Rieke, J.; Schmidt, M.; Wasem, T.; Achenbach, P.; Cardinali, M.; Hoek, M.; Lauth, W.; Schlimme, S.; Sfienti, C.; Thiel, M.

2018-03-01

The PANDA experiment at the international accelerator Facility for Antiproton and Ion Research in Europe (FAIR) near GSI, Darmstadt, Germany will address fundamental questions of hadron physics. Excellent Particle Identification (PID) over a large range of solid angles and particle momenta will be essential to meet the objectives of the rich physics program. Charged PID for the barrel region of the PANDA target spectrometer will be provided by a DIRC (Detection of Internally Reflected Cherenkov light) detector. The Barrel DIRC will cover the polar angle range of 22o-140o and cleanly separate charged pions from kaons for momenta between 0.5 GeV/c and 3.5 GeV/c with a separation power of at least 3 standard deviations. The design is based on the successful BABAR DIRC and the SuperB FDIRC R&D with several important improvements to optimize the performance for PANDA, such as a focusing lens system, fast timing, a compact fused silica prism as expansion region, and lifetime-enhanced Microchannel-Plate PMTs for photon detection. This article describes the technical design of the PANDA Barrel DIRC and the result of the design validation using a "vertical slice" prototype in hadronic particle beams at the CERN PS.

Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam

Energy Technology Data Exchange (ETDEWEB)

Abat, E; Arik, E [Bogazici University, Faculty of Sciences, Department of Physics, TR-80815 Bebek-Istanbul (Turkey); Abdallah, J M [Institut de Fisica d' Altes Energies, IFAE, Universitat Autonoma de Barcelona, Edifici Cn, ES-08193 Bellaterra, Barcelona (Spain); Addy, T N [Hampton University, Department of Physics, Hampton, VA 23668 (United States); Adragna, P [Queen Mary, University of London, Mile End Road, E1 4NS, London (United Kingdom); Aharrouche, M [Universitaet Mainz, Institut fuer Physik, Staudinger Weg 7, DE-55099 (Germany); Ahmad, A [Insitute of Physics, Academia Sinica, TW-Taipei 11529, Taiwan (China); Akesson, T P A [Lunds universitet, Naturvetenskapliga fakulteten, Fysiska institutionen, Box 118, SE-221 00, Lund (Sweden); Aleksa, M; Anghinolfi, F; Baron, S [European Laboratory for Particle Physics (CERN), CH-1211 Geneva 23 (Switzerland); Alexa, C [National Institute of Physics and Nuclear Engineering (Bucharest -IFIN-HH), P.O. Box MG-6, R-077125 Bucharest (Romania); Anderson, K [University of Chicago, Enrico Fermi Institute, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Andreazza, A; Banfi, D [INFN Sezione di Milano, via Celoria 16, IT-20133 Milano (Italy); Antonaki, A; Arabidze, G [University of Athens, Nuclear and Particle Physics Department of Physics, Panepistimiopouli Zografou, GR 15771 Athens (Greece); Atkinson, T [School of Physics, University of Melbourne, AU-Parkvill, Victoria 3010 (Australia); Baines, J [Rutherford Appleton Laboratory, Science and Technology Facilities Council, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Baker, O K, E-mail: stathes.paganis@cern.ch [Yale University, Department of Physics, PO Box 208121, New Haven, CT06520-8121 (United States)

2011-04-01

The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal development of the electromagnetic shower between converted and unconverted photons as well as in the total measured energy. The potential to use the reconstructed converted photons as a means to precisely map the material of the tracker in front of the electromagnetic calorimeter is also considered. All results obtained are compared with a detailed Monte-Carlo simulation of the test-beam setup which is based on the same simulation and reconstruction tools as those used for the ATLAS detector itself.

Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam

International Nuclear Information System (INIS)

Abat, E; Arik, E; Abdallah, J M; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Anghinolfi, F; Baron, S; Alexa, C; Anderson, K; Andreazza, A; Banfi, D; Antonaki, A; Arabidze, G; Atkinson, T; Baines, J; Baker, O K

2011-01-01

The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal development of the electromagnetic shower between converted and unconverted photons as well as in the total measured energy. The potential to use the reconstructed converted photons as a means to precisely map the material of the tracker in front of the electromagnetic calorimeter is also considered. All results obtained are compared with a detailed Monte-Carlo simulation of the test-beam setup which is based on the same simulation and reconstruction tools as those used for the ATLAS detector itself.

Studies for a common selection software environment in ATLAS from the Level-2 Trigger to the offline reconstruction

CERN Document Server

Wiedenmann, W; Baines, J T M; Bee, C P; Biglietti, M; Bogaerts, A; Boisvert, V; Bosman, M; Brandt, S; Caron, B; Casado, M P; Cataldi, G; Cavalli, D; Cervetto, M; Comune, G; Corso-Radu, A; Di Mattia, A; Díaz-Gómez, M; Dos Anjos, A; Drohan, J; Ellis, Nick; Elsing, M; Epp, B; Etienne, F; Falciano, S; Farilla, A; George, S; Ghete, V M; González, S; Grothe, M; Kaczmarska, A; Karr, K M; Khomich, A; Konstantinidis, N P; Krasny, W; Li, W; Lowe, A; Luminari, L; Meessen, C; Mello, A G; Merino, G; Morettini, P; Moyse, E; Nairz, A; Negri, A; Nikitin, N V; Nisati, A; Padilla, C; Parodi, F; Pérez-Réale, V; Pinfold, J L; Pinto, P; Polesello, G; Qian, Z; Resconi, S; Rosati, S; Scannicchio, D A; Schiavi, C; Schörner-Sadenius, T; Segura, E; De Seixas, J M; Shears, T G; Sivoklokov, S Yu; Smizanska, M; Soluk, R A; Stanescu, C; Tapprogge, Stefan; Touchard, F; Vercesi, V; Watson, A T; Wengler, T; Werner, P; Wheeler, S; Wickens, F J; Wielers, M; Zobernig, G; NSS-MIC 2003 - IEEE Nuclear Science Symposium and Medical Imaging Conference, Part 1

2004-01-01

The Atlas High Level Trigger's primary function of event selection will be accomplished with a Level-2 trigger farm and an Event Filter farm, both running software components developed in the Atlas offline reconstruction framework. While this approach provides a unified software framework for event selection, it poses strict requirements on offline components critical for the Level-2 trigger. A Level-2 decision in Atlas must typically be accomplished within 10 ms and with multiple event processing in concurrent threads. In order to address these constraints, prototypes have been developed that incorporate elements of the Atlas Data Flow -, High Level Trigger -, and offline framework software. To realize a homogeneous software environment for offline components in the High Level Trigger, the Level-2 Steering Controller was developed. With electron/gamma- and muon-selection slices it has been shown that the required performance can be reached, if the offline components used are carefully designed and optimized ...

The ATLAS High Level Trigger Configuration and Steering, Experience with the First 7 TeV Collisions

CERN Document Server

Stelzer, J; The ATLAS collaboration

2011-01-01

In March 2010 the four LHC experiments saw the first proton-proton collisions at a center-of-mass energy of 7 TeV. Still within the year a collision rate of nearly 10 MHz was expected. At ATLAS, events of potential physics interest for are selected by a three-level trigger system, with a final recording rate of about 200 Hz. The first level (L1) is implemented in customized hardware, the two levels of the high level trigger (HLT) are software triggers. For the ATLAS physics program more than 500 trigger signatures are defined. The HLT tests each signature on each L1-accepted event, the test outcome is recorded for later analysis. The HLT-Steering is responsible for this. It foremost ensures the independence of each signature test and an unbiased trigger decisions. Yet, to minimize data readout and execution time, cached detector data and once-calculated trigger objects are reused to form the decision. Some signature tests are performed only on a scaled-down fraction of candidate events, in order to reduce the...

The normal zone propagation in ATLAS B00 model coil

CERN Document Server

Boxman, E W; ten Kate, H H J

2002-01-01

The B00 model coil has been successfully tested in the ATLAS Magnet Test Facility at CERN. The coil consists of two double pancakes wound with aluminum stabilized cables of the barrel- and end-cap toroids conductors for the ATLAS detector. The magnet current is applied up to 24 kA and quenches are induced by firing point heaters. The normal zone velocity is measured over a wide range of currents by using pickup coils, voltage taps and superconducting quench detectors. The signals coming from various sensors are presented and analyzed. The results extracted from the various detection methods are in good agreement. It is found that the characteristic velocities vary from 5 to 20 m/s at 15 and 24 kA respectively. In addition, the minimum quench energies at different applied magnet currents are presented. (6 refs).

ATLAS irradiation studies of n-in-n and p-in-n silicon microstrip detectors

CERN Document Server

Allport, P P; Buttar, C M; Carter, J; Drage, L M; Ferrère, D; Morgan, D; Riedler, P; Robinson, D

1999-01-01

Prior to the module production of the ATLAS silicon microstrip tracker for the barrel and the forward wheels, the characterisation of full-size prototype silicon detectors after radiation to fluences corresponding to 10 years of ATLAS operation is required. The behaviour of p-in-n and n-in-n detectors produced by several manufacturers before and after irradiation to a fluence of 3*10/sup 14/ protons/cm/sup 2/ at the CERN PS facility is discussed. This article summarises some recent results from the ATLAS SCT collaboration. The measurements of leakage current, full depletion voltage, signal-to-noise ratio and charge collection efficiency are presented. Despite the better efficiency performance of n-in-n detectors below depletion, the collaboration chose the p-in-n technology due to its simpler and less costly production since good charge collection efficiencies were achieved at the desired maximum bias voltage. (14 refs).

Water-Soluble Pd8L4 Self-assembled Molecular Barrel as an Aqueous Carrier for Hydrophobic Curcumin.

Science.gov (United States)

Bhat, Imtiyaz Ahmad; Jain, Ruchi; Siddiqui, Mujahuddin M; Saini, Deepak K; Mukherjee, Partha Sarathi

2017-05-01

A tetrafacial water-soluble molecular barrel (1) was synthesized by coordination driven self-assembly of a symmetrical tetrapyridyl donor (L) with a cis-blocked 90° acceptor [cis-(en)Pd(NO 3 ) 2 ] (en = ethane-1,2-diamine). The open barrel structure of (1) was confirmed by single crystal X-ray diffraction. The presence of a hydrophobic cavity with large windows makes it an ideal candidate for encapsulation and carrying hydrophobic drug like curcumin in an aqueous medium. The barrel (1) encapsulates curcumin inside its molecular cavity and protects highly photosensitive curcumin from photodegradation. The photostability of encapsulated curcumin is due to the absorption of a high proportion of the incident photons by the aromatic walls of 1 with a high absorption cross-sectional area, which helps the walls to shield the guest even against sunlight/UV radiations. As compared to free curcumin in water, we noticed a significant increase in solubility as well as cellular uptake of curcumin upon encapsulation inside the water-soluble molecular barrel (1) in aqueous medium. Fluorescence imaging confirmed that curcumin was delivered into HeLa cancer cells by the aqueous barrel (1) with the retention of its potential anticancer activity. While free curcumin is inactive toward cancer cells in aqueous medium at room temperature due to negligible solubility, the determined IC 50 value of ∼14 μM for curcumin in aqueous medium in the presence of the barrel (1) reflects the efficiency of the barrel as a potential curcumin carrier in aqueous medium without any other additives. Thus, two major challenges of increasing the bioavailability and stability of curcumin in aqueous medium even in the presence of UV light have been addressed by using a new supramolecular water-soluble barrel (1) as a drug carrier.