AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux

Energy Technology Data Exchange (ETDEWEB)

Halzen, Francis; /Wisconsin U., Madison; Hooper, Dan; /Fermilab

2006-05-01

A number of experimental techniques are currently being deployed in an effort to make the first detection of ultra-high energy cosmic neutrinos. To accomplish this goal, techniques using radio and acoustic detectors are being developed, which are optimally designed for studying neutrinos with energies in the PeV-EeV range and above. Data from the AMANDA experiment, in contrast, has been used to place limits on the cosmic neutrino flux at less extreme energies (up to {approx}10 PeV). In this letter, we show that by adopting a different analysis strategy, optimized for much higher energy neutrinos, the same AMANDA data can be used to place a limit competitive with radio techniques at EeV energies. We also discuss the sensitivity of the IceCube experiment, in various stages of deployment, to ultra-high energy neutrinos.

Amanda Cross and Androgyny

Directory of Open Access Journals (Sweden)

Kania Richard R. E.

2016-12-01

Full Text Available Amanda Cross is the pen name Carolyn Heilbrun used for her mystery fiction. In two of her novels she employed the theme of androgyny. She also wrote the non-fiction, 1973 Toward a Recognition of Androgyny in which she promoted androgyny as aspect of her approach to feminism, an intellectual denial of any significant differences between the sexes. While that thread of American feminism has lost favor in current feminist ideologies, matters of gender identity are rising in prominence in American social and political thought, reviving the debate on male and female roles and identities in the United States.

Software-triggered contrast-enhanced three-dimensional MR angiography of the intracranial arteries.

Science.gov (United States)

Isoda, H; Takehara, Y; Isogai, S; Takeda, H; Tanaka, T; Takahashi, M; Nozaki, A; Sun, Y

2000-02-01

We investigated the effectiveness of software-triggered contrast-enhanced three-dimensional (3D) MR angiography in evaluating intracranial arteries. We studied 38 patients with suspected brain lesions. Imaging was performed using a 1.5-T superconducting MR system with a commercially available head coil. To monitor signal intensity changes we used software to place a tracker volume at the basilar artery or the internal carotid artery. A 20-ml bolus of gadodiamide hydrate was administered through the antecubital vein at a rate of 2-4 ml/sec, followed by a saline flush. Three-dimensional MR angiography using a spoiled gradient-echo sequence with centric K-space ordering was triggered by the arrival of the contrast bolus in the tracker volume. Imaging times ranged from 12 to 20 sec. We used MR images to assess the effectiveness of contrast-enhanced 3D MR angiography in revealing intracranial arteries with minimal venous overlap. The software triggered imaging on the arrival of the contrast bolus in 81.6% of examinations. In 77.6% of examinations, the resulting MR angiograms revealed intracranial arteries with minimal venous overlap. Software-triggered contrast-enhanced 3D MR angiography with centric K-space ordering is a promising technique for viewing intracranial arteries.

Method for detecting neutrinos from internal shocks in GRB fireballs with AMANDA

CERN Document Server

Stamatikos, M

2004-01-01

Neutrino-based astronomy provides a new window on the most energetic processes in the universe. The discovery of high-energy (E >or= 10 /sup 14/ eV) muonic neutrinos (v/sub mu /) from gamma-ray bursts (GRBs) would confirm hadronic acceleration in the relativistic GRB- wind, validate the phenomenology of the canonical fireball model and possibly reveal an acceleration mechanism for the highest energy cosmic rays (CRs). The Antarctic Muon and Neutrino Detector Array (AMANDA) is the world's largest operational neutrino telescope with a PeV muon effective area (averaged over zenith angle) ~ 50,000 m/sup 2 /. AMANDA uses the natural ice at the geographic South Pole as a Cherenkov medium and has been successfully calibrated on the signal of atmospheric neutrinos (v/sub atm/). Contrary to previous diffuse searches, we describe an analysis based upon confronting AMANDA observations of individual GRBs, adequately modeled by fireball phenomenology, with the predictions of the canonical fireball model. The expected neut...

The D OE software trigger

International Nuclear Information System (INIS)

Linnemann, J.T.; Michigan State Univ., East Lansing, MI

1992-10-01

In the D OE experiment, the software filter operates in a processor farm with each node processing a single event. Processing is data-driven: the filter does local processing to verify the candidates from the hardware trigger. The filter code consists of independent pieces called ''tools''; processing for a given hardware bit is a ''script'' invoking one or more ''tools'' sequentially. An offline simulator drives the same code with the same configuration files, running on real or simulated data. Online tests use farm nodes parasiting on the data stream. We discuss the performance of the system and how we attempt to verify its correctness

An Alternative Flight Software Trigger Paradigm: Applying Multivariate Logistic Regression to Sense Trigger Conditions Using Inaccurate or Scarce Information

Science.gov (United States)

Smith, Kelly M.; Gay, Robert S.; Stachowiak, Susan J.

2013-01-01

In late 2014, NASA will fly the Orion capsule on a Delta IV-Heavy rocket for the Exploration Flight Test-1 (EFT-1) mission. For EFT-1, the Orion capsule will be flying with a new GPS receiver and new navigation software. Given the experimental nature of the flight, the flight software must be robust to the loss of GPS measurements. Once the high-speed entry is complete, the drogue parachutes must be deployed within the proper conditions to stabilize the vehicle prior to deploying the main parachutes. When GPS is available in nominal operations, the vehicle will deploy the drogue parachutes based on an altitude trigger. However, when GPS is unavailable, the navigated altitude errors become excessively large, driving the need for a backup barometric altimeter to improve altitude knowledge. In order to increase overall robustness, the vehicle also has an alternate method of triggering the parachute deployment sequence based on planet-relative velocity if both the GPS and the barometric altimeter fail. However, this backup trigger results in large altitude errors relative to the targeted altitude. Motivated by this challenge, this paper demonstrates how logistic regression may be employed to semi-automatically generate robust triggers based on statistical analysis. Logistic regression is used as a ground processor pre-flight to develop a statistical classifier. The classifier would then be implemented in flight software and executed in real-time. This technique offers improved performance even in the face of highly inaccurate measurements. Although the logistic regression-based trigger approach will not be implemented within EFT-1 flight software, the methodology can be carried forward for future missions and vehicles.

Development, Validation and Integration of the ATLAS Trigger System Software in Run 2

CERN Document Server

Keyes, Robert; The ATLAS collaboration

2016-01-01

The trigger system of the ATLAS detector at the LHC is a combination of hardware, firmware and software, associated to various sub-detectors that must seamlessly cooperate in order to select 1 collision of interest out of every 40,000 delivered by the LHC every millisecond. This talk will discuss the challenges, workflow and organization of the ongoing trigger software development, validation and deployment. This development, from the top level integration and configuration to the individual components responsible for each sub system, is done to ensure that the most up to date algorithms are used to optimize the performance of the experiment. This optimization hinges on the reliability and predictability of the software performance, which is why validation is of the utmost importance. The software adheres to a hierarchical release structure, with newly validated releases propagating upwards. Integration tests are carried out on a daily basis to ensure that the releases deployed to the online trigger farm duri...

Development, Validation and Integration of the ATLAS Trigger System Software in Run 2

Science.gov (United States)

Keyes, Robert; ATLAS Collaboration

2017-10-01

The trigger system of the ATLAS detector at the LHC is a combination of hardware, firmware, and software, associated to various sub-detectors that must seamlessly cooperate in order to select one collision of interest out of every 40,000 delivered by the LHC every millisecond. These proceedings discuss the challenges, organization and work flow of the ongoing trigger software development, validation, and deployment. The goal of this development is to ensure that the most up-to-date algorithms are used to optimize the performance of the experiment. The goal of the validation is to ensure the reliability and predictability of the software performance. Integration tests are carried out to ensure that the software deployed to the online trigger farm during data-taking run as desired. Trigger software is validated by emulating online conditions using a benchmark run and mimicking the reconstruction that occurs during normal data-taking. This exercise is computationally demanding and thus runs on the ATLAS high performance computing grid with high priority. Performance metrics ranging from low-level memory and CPU requirements, to distributions and efficiencies of high-level physics quantities are visualized and validated by a range of experts. This is a multifaceted critical task that ties together many aspects of the experimental effort and thus directly influences the overall performance of the ATLAS experiment.

A calorimeter software trigger for the Mark II detector at SLC [Stanford Linear Collider

International Nuclear Information System (INIS)

Briggs, D.; Glanzman, T.; Grosse-Wiesmann, P.; Tinsman, J.; Holmgren, S.; Schaad, M.W.

1989-04-01

A new FASTBUS-based calorimeter software trigger for the upgraded Mark II at the Stanford Linear Collider (SLC) is presented. The trigger requirements for SLC and a short description of the hardware used for this purpose are given, followed by a detailed description of the software. Some preliminary results are presented. 9 refs., 4 figs

Muon track reconstruction and data selection techniques in AMANDA

International Nuclear Information System (INIS)

Ahrens, J.; Bai, X.; Bay, R.; Barwick, S.W.; Becka, T.; Becker, J.K.; Becker, K.-H.; Bernardini, E.; Bertrand, D.; Biron, A.; Boersma, D.J.; Boeser, S.; Botner, O.; Bouchta, A.; Bouhali, O.; Burgess, T.; Carius, S.; Castermans, T.; Chirkin, D.; Collin, B.; Conrad, J.; Cooley, J.; Cowen, D.F.; Davour, A.; De Clercq, C.; DeYoung, T.; Desiati, P.; Dewulf, J.-P.; Ekstroem, P.; Feser, T.; Gaug, M.; Gaisser, T.K.; Ganugapati, R.; Geenen, H.; Gerhardt, L.; Gross, A.; Goldschmidt, A.; Hallgren, A.; Halzen, F.; Hanson, K.; Hardtke, R.; Harenberg, T.; Hauschildt, T.; Helbing, K.; Hellwig, M.; Herquet, P.; Hill, G.C.; Hubert, D.; Hughey, B.; Hulth, P.O.; Hultqvist, K.; Hundertmark, S.; Jacobsen, J.; Karle, A.; Kestel, M.; Koepke, L.; Kowalski, M.; Kuehn, K.; Lamoureux, J.I.; Leich, H.; Leuthold, M.; Lindahl, P.; Liubarsky, I.; Madsen, J.; Marciniewski, P.; Matis, H.S.; McParland, C.P.; Messarius, T.; Minaeva, Y.; Miocinovic, P.; Mock, P.C.; Morse, R.; Muenich, K.S.; Nam, J.; Nahnhauer, R.; Neunhoeffer, T.; Niessen, P.; Nygren, D.R.; Oegelman, H.; Olbrechts, Ph.; Perez de los Heros, C.; Pohl, A.C.; Porrata, R.; Price, P.B.; Przybylski, G.T.; Rawlins, K.; Resconi, E.; Rhode, W.; Ribordy, M.; Richter, S.; Rodriguez Martino, J.; Ross, D.; Sander, H.-G.; Schinarakis, K.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Schwarz, R.; Silvestri, A.; Solarz, M.; Spiczak, G.M.; Spiering, C.; Stamatikos, M.; Steele, D.; Steffen, P.; Stokstad, R.G.; Sulanke, K.-H.; Streicher, O.; Taboada, I.; Thollander, L.; Tilav, S.; Wagner, W.; Walck, C.; Wang, Y.-R.; Wiebusch, C.H.; Wiedemann, C.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Yodh, G.

2004-01-01

The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500 and 2000 m. The primary goal of this detector is to discover astrophysical sources of high-energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of reconstruction, which have been successfully implemented within AMANDA. Strategies for optimizing the reconstruction performance and rejecting background are presented. For a typical analysis procedure the direction of tracks are reconstructed with about 2 deg. accuracy

A Python extension to the ATLAS online software for the thin gap chamber trigger system

CERN Document Server

Maeno, Tadashi; Komatsu, Satoru; Nakayoshi, Kazuo; Yasu, Yoshiji

2004-01-01

A Python extension module for A Toroidal LHC Apparatus (ATLAS) Online Software has been developed for the Thin Gap Chamber (TGC) trigger system. Python is an interactive scripting language including built- in high-level libraries, and provides an easy way to build Web applications. These features are not included in the Online Software, and are important in developing test software for the TGC trigger system. The Python extension module is designed and implemented using a C++ library, "Boost.Python." We have developed a Web application using the extension module and Zope (a Python-based Web application server), which allows one to monitor the TGC trigger system from anywhere in the world. The functionalities of the Python extension module and its application for the TGC trigger system are presented. 7 Refs.

Search for Ultra High-Energy Neutrinos with AMANDA-II

International Nuclear Information System (INIS)

IceCube Collaboration; Klein, Spencer; Ackermann, M.

2007-01-01

A search for diffuse neutrinos with energies in excess of 10 5 GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10 7 GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E 2 Φ 90%CL -7 GeV cm -2 s -1 sr -1 valid over the energy range of 2 x 10 5 GeV to 10 9 GeV. A number of models which predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level

Results from the AMANDA detector

CERN Document Server

Ackermann, M; Albrecht, H; Bai, X; Bartelt, M; Barwick, S W; Bay, R; Becka, T; Becker, J K; Becker, K H; Bernardini, E; Bertrand, D; Boersma, D J; Boser, S; Botner, O; Bouchta, A; Bouhali, O; Braun, J; Burgess, C; Burgess, T; Castermans, T; Chirkin, D; Collin, B; Conrad, J; Cooley, J; Cowen, D F; Davour, A; De Clercq, C; Pérez de los Heros, C; De Young, T R; Desiati, P; Ekstrom, P; Feser, T; Gaisser, T K; Ganugapati, R; Geenen, H; Gerhardt, L; Goldschmidt, A; Gross, A; Hallgren, A; Halzen, F; Hanson, K; Hardtke, R; Harenberg, T; Hauschildt, T; Helbing, K; Hellwig, M; Herquet, P; Hill, G C; Hodges, J; Hubert, D; Hughey, B; Hulth, P O; Hultqvist, K; Hundertmark, S; Jacobsen, J; Kampert, K H; Karle, A; Kelley, J; Kestel, M; Köpke, L; Kowalski, M; Krasberg, M; Kühn, K; Leich, H; Leuthold, M; Liubarsky, I; Madsen, J; Mandli, K; Marciniewski, P; Martino, J R; Matis, H S; McParland, C P; Messarius, T; Minaeva, Y; Miocinovic, P; Morse, R; Munich, K; Nahnhauer, R; Nam, J W; Neunhoffer, T; Niessen, P; Nygren, D R; Ogelman, H; Olbrechts, P; Pohl, A C; Porrata, R; Price, P B; Przybylski, G T; Rawlins, K; Resconi, E; Rhode, W; Ribordy, M; Richter, S; Sander, H G; Schinarakis, K; Schlenstedt, S; Schneider, D; Schwarz, R; Silvestri, A; Solarz, M; Spiczak, G M; Spiering, C; Stamatikos, M; Steele, D; Steffen, P; Stokstad, R G; Sulanke, K H; Taboada, I; Thollander, L; Tilav, S; Wagner, W; Walck, C; Walter, M; Wang, Y R; Wiebusch, C; Wischnewski, R; Wissing, H; Woschnagg, K; Yodh, G

2004-01-01

The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high- energy neutrino telescope based at the geographic south pole. It is a lattice of photomultiplier tubes buried deep in the polar ice, which is used as interaction and detection medium. The primary goal of this detector is the observation of astronomical sources of high-energy neutrinos. This paper shows the latest results of the search for a diffuse flux of extraterrestrial nu /sub mu /s with energies between 10/sup 11/ eV and 10/sup 18/ eV, nu /sub mu /s emitted from point sources and nu /sub mu /s from dark matter annihilation in the Earth and the Sun.

HEP Community White Paper on Software Trigger and Event Reconstruction

Energy Technology Data Exchange (ETDEWEB)

Albrecht, Johannes; et al.

2018-02-23

Realizing the physics programs of the planned and upgraded high-energy physics (HEP) experiments over the next 10 years will require the HEP community to address a number of challenges in the area of software and computing. For this reason, the HEP software community has engaged in a planning process over the past two years, with the objective of identifying and prioritizing the research and development required to enable the next generation of HEP detectors to fulfill their full physics potential. The aim is to produce a Community White Paper which will describe the community strategy and a roadmap for software and computing research and development in HEP for the 2020s. The topics of event reconstruction and software triggers were considered by a joint working group and are summarized together in this document.

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 ...

Selected recent results from AMANDA

CERN Document Server

Andrés, E; Bai, X; Barouch, G; Barwick, S W; Bay, R C; Becker, K H; Bergström, L; Bertrand, D; Bierenbaum, D; Biron, A; Booth, J; Botner, O; Bouchta, A; Boyce, M M; Carius, S; Chen, A; Chirkin, D; Conrad, J; Cooley, J; Costa, C G S; Cowen, D F; Dailing, J; Dalberg, E; De Young, T R; Desiati, P; Dewulf, J P; Doksus, P; Edsjö, J; Ekstrom, P; Erlandsson, B; Feser, T; Gaug, M; Goldschmidt, A; Goobar, A; Gray, L; Haase, H; Hallgren, A; Halzen, F; Hanson, K; Hardtke, R; He, Y D; Hellwig, M; Heukenkamp, H; Hill, G C; Hulth, P O; Hundertmark, S; Jacobsen, J; Kandhadai, V; Karle, A; Kim, J; Koci, B; Köpke, L; Kowalski, M; Leich, H; Leuthold, M; Lindahl, P; Liubarsky, I; Loaiza, P; Lowder, D M; Ludvig, J; Madsen, J; Marciniewski, P; Matis, H S; Mihályi, A; Mikolajski, T; Miller, T C; Minaeva, Y; Miocinovic, P; Mock, P C; Morse, R; Neunhoffer, T; Newcomer, F M; Niessen, P; Nygren, D R; Ogelman, H; Heros, C P D L; Porrata, R; Price, P B; Rawlins, K; Reed, C; Rhode, W; Richards, A; Richter, S; Martino, J R; Romenesko, P; Ross, D; Rubinstein, H; Sander, H G; Scheider, T; Schmidt, T; Schneider, D; Schneider, E; Schwarzl, R; Silvestri, A; Solarz, M; Spiczak, G M; Spiering, C; Starinsky, N; Steele, D; Steffen, P; Stokstad, R G; Streicher, O; Sun, A; Taboada, I; Thollander, L; Thon, T; Tilav, S; Usechak, N; Donckt, M V; Walck, C; Weinheimer, C; Wiebusch, C; Wischnewski, R; Wissing, H; Woschnagg, K; Wu, W; Yodh, G; Young, S

2001-01-01

We present a selection of results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope. Studies of nearly vertical upgoing muons limit the available parameter space for WIMP dark matter under the assumption that WIMPS are trapped in the earth's gravitational potential well and annihilate with one another near the earth's center.

Geochemical record of high emperor penguin populations during the Little Ice Age at Amanda Bay, Antarctica

Energy Technology Data Exchange (ETDEWEB)

Huang, Tao, E-mail: huangt@ahu.edu.cn [School of Resources and Environmental Engineering, Anhui University, Hefei 230601 (China); School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Yang, Lianjiao; Chu, Zhuding [School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Sun, Liguang, E-mail: slg@ustc.edu.cn [School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Yin, Xijie [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005 (China)

2016-09-15

Emperor penguins (Aptenodytes forsteri) are sensitive to the Antarctic climate change because they breed on the fast sea ice. Studies of paleohistory for the emperor penguin are rare, due to the lack of archives on land. In this study, we obtained an emperor penguin ornithogenic sediment profile (PI) and performed geochronological, geochemical and stable isotope analyses on the sediments and feather remains. Two radiocarbon dates of penguin feathers in PI indicate that emperor penguins colonized Amanda Bay as early as CE 1540. By using the bio-elements (P, Se, Hg, Zn and Cd) in sediments and stable isotope values (δ{sup 15}N and δ{sup 13}C) in feathers, we inferred relative population size and dietary change of emperor penguins during the period of CE 1540–2008, respectively. An increase in population size with depleted N isotope ratios for emperor penguins on N island at Amanda Bay during the Little Ice Age (CE 1540–1866) was observed, suggesting that cold climate affected the penguin's breeding habitat, prey availability and thus their population and dietary composition. - Highlights: • Emperor penguin colonized at Amanda Bay, East Antarctic as early as AD 1540. • Populations of emperor penguin at Amanda Bay increase during the little ice age. • Depleted N isotope ratios of Emperor penguins during the LIA were observed.

Geochemical record of high emperor penguin populations during the Little Ice Age at Amanda Bay, Antarctica

International Nuclear Information System (INIS)

Huang, Tao; Yang, Lianjiao; Chu, Zhuding; Sun, Liguang; Yin, Xijie

2016-01-01

Emperor penguins (Aptenodytes forsteri) are sensitive to the Antarctic climate change because they breed on the fast sea ice. Studies of paleohistory for the emperor penguin are rare, due to the lack of archives on land. In this study, we obtained an emperor penguin ornithogenic sediment profile (PI) and performed geochronological, geochemical and stable isotope analyses on the sediments and feather remains. Two radiocarbon dates of penguin feathers in PI indicate that emperor penguins colonized Amanda Bay as early as CE 1540. By using the bio-elements (P, Se, Hg, Zn and Cd) in sediments and stable isotope values (δ"1"5N and δ"1"3C) in feathers, we inferred relative population size and dietary change of emperor penguins during the period of CE 1540–2008, respectively. An increase in population size with depleted N isotope ratios for emperor penguins on N island at Amanda Bay during the Little Ice Age (CE 1540–1866) was observed, suggesting that cold climate affected the penguin's breeding habitat, prey availability and thus their population and dietary composition. - Highlights: • Emperor penguin colonized at Amanda Bay, East Antarctic as early as AD 1540. • Populations of emperor penguin at Amanda Bay increase during the little ice age. • Depleted N isotope ratios of Emperor penguins during the LIA were observed.

Testing on a Large Scale Running the ATLAS Data Acquisition and High Level Trigger Software on 700 PC Nodes

CERN Document Server

Burckhart-Chromek, Doris; Adragna, P; Alexandrov, L; Amorim, A; Armstrong, S; Badescu, E; Baines, J T M; Barros, N; Beck, H P; Bee, C; Blair, R; Bogaerts, J A C; Bold, T; Bosman, M; Caprini, M; Caramarcu, C; Ciobotaru, M; Comune, G; Corso-Radu, A; Cranfield, R; Crone, G; Dawson, J; Della Pietra, M; Di Mattia, A; Dobinson, Robert W; Dobson, M; Dos Anjos, A; Dotti, A; Drake, G; Ellis, Nick; Ermoline, Y; Ertorer, E; Falciano, S; Ferrari, R; Ferrer, M L; Francis, D; Gadomski, S; Gameiro, S; Garitaonandia, H; Gaudio, G; George, S; Gesualdi-Mello, A; Gorini, B; Green, B; Haas, S; Haberichter, W N; Hadavand, H; Haeberli, C; Haller, J; Hansen, J; Hauser, R; Hillier, S J; Höcker, A; Hughes-Jones, R E; Joos, M; Kazarov, A; Kieft, G; Klous, S; Kohno, T; Kolos, S; Korcyl, K; Kordas, K; Kotov, V; Kugel, A; Landon, M; Lankford, A; Leahu, L; Leahu, M; Lehmann-Miotto, G; Le Vine, M J; Liu, W; Maeno, T; Männer, R; Mapelli, L; Martin, B; Masik, J; McLaren, R; Meessen, C; Meirosu, C; Mineev, M; Misiejuk, A; Morettini, P; Mornacchi, G; Müller, M; Garcia-Murillo, R; Nagasaka, Y; Negri, A; Padilla, C; Pasqualucci, E; Pauly, T; Perera, V; Petersen, J; Pope, B; Albuquerque-Portes, M; Pretzl, K; Prigent, D; Roda, C; Ryabov, Yu; Salvatore, D; Schiavi, C; Schlereth, J L; Scholtes, I; Sole-Segura, E; Seixas, M; Sloper, J; Soloviev, I; Spiwoks, R; Stamen, R; Stancu, S; Strong, S; Sushkov, S; Szymocha, T; Tapprogge, S; Teixeira-Dias, P; Torres, R; Touchard, F; Tremblet, L; Ünel, G; Van Wasen, J; Vandelli, W; Vaz-Gil-Lopes, L; Vermeulen, J C; von der Schmitt, H; Wengler, T; Werner, P; Wheeler, S; Wickens, F; Wiedenmann, W; Wiesmann, M; Wu, X; Yasu, Y; Yu, M; Zema, F; Zobernig, H; Computing In High Energy and Nuclear Physics

2006-01-01

The ATLAS Data Acquisition (DAQ) and High Level Trigger (HLT) software system will be comprised initially of 2000 PC nodes which take part in the control, event readout, second level trigger and event filter operations. This high number of PCs will only be purchased before data taking in 2007. The large CERN IT LXBATCH facility provided the opportunity to run in July 2005 online functionality tests over a period of 5 weeks on a stepwise increasing farm size from 100 up to 700 PC dual nodes. The interplay between the control and monitoring software with the event readout, event building and the trigger software has been exercised the first time as an integrated system on this large scale. New was also to run algorithms in the online environment for the trigger selection and in the event filter processing tasks on a larger scale. A mechanism has been developed to package the offline software together with the DAQ/HLT software and to distribute it via peer-to-peer software efficiently to this large pc cluster. T...

Testing on a Large Scale running the ATLAS Data Acquisition and High Level Trigger Software on 700 PC Nodes

CERN Document Server

Burckhart-Chromek, Doris; Adragna, P; Albuquerque-Portes, M; Alexandrov, L; Amorim, A; Armstrong, S; Badescu, E; Baines, J T M; Barros, N; Beck, H P; Bee, C; Blair, R; Bogaerts, J A C; Bold, T; Bosman, M; Caprini, M; Caramarcu, C; Ciobotaru, M; Comune, G; Corso-Radu, A; Cranfield, R; Crone, G; Dawson, J; Della Pietra, M; Di Mattia, A; Dobinson, Robert W; Dobson, M; Dos Anjos, A; Dotti, A; Drake, G; Ellis, Nick; Ermoline, Y; Ertorer, E; Falciano, S; Ferrari, R; Ferrer, M L; Francis, D; Gadomski, S; Gameiro, S; Garcia-Murillo, R; Garitaonandia, H; Gaudio, G; George, S; Gesualdi-Mello, A; Gorini, B; Green, B; Haas, S; Haberichter, W N; Hadavand, H; Haeberli, C; Haller, J; Hansen, J; Hauser, R; Hillier, S J; Hughes-Jones, R E; Höcker, A; Joos, M; Kazarov, A; Kieft, G; Klous, S; Kohno, T; Kolos, S; Korcyl, K; Kordas, K; Kotov, V; Kugel, A; Landon, M; Lankford, A; Le Vine, M J; Leahu, L; Leahu, M; Lehmann-Miotto, G; Liu, W; Maeno, T; Mapelli, L; Martin, B; Masik, J; McLaren, R; Meessen, C; Meirosu, C; Mineev, M; Misiejuk, A; Morettini, P; Mornacchi, G; Männer, R; Müller, M; Nagasaka, Y; Negri, A; Padilla, C; Pasqualucci, E; Pauly, T; Perera, V; Petersen, J; Pope, B; Pretzl, K; Prigent, D; Roda, C; Ryabov, Yu; Salvatore, D; Schiavi, C; Schlereth, J L; Scholtes, I; Seixas, M; Sloper, J; Sole-Segura, E; Soloviev, I; Spiwoks, R; Stamen, R; Stancu, S; Strong, S; Sushkov, S; Szymocha, T; Tapprogge, S; Teixeira-Dias, P; Torres, R; Touchard, F; Tremblet, L; Van Wasen, J; Vandelli, W; Vaz-Gil-Lopes, L; Vermeulen, J C; Wengler, T; Werner, P; Wheeler, S; Wickens, F; Wiedenmann, W; Wiesmann, M; Wu, X; Yasu, Y; Yu, M; Zema, F; Zobernig, H; von der Schmitt, H; Ünel, G; Computing In High Energy and Nuclear Physics

2006-01-01

The ATLAS Data Acquisition (DAQ) and High Level Trigger (HLT) software system will be comprised initially of 2000 PC nodes which take part in the control, event readout, second level trigger and event filter operations. This high number of PCs will only be purchased before data taking in 2007. The large CERN IT LXBATCH facility provided the opportunity to run in July 2005 online functionality tests over a period of 5 weeks on a stepwise increasing farm size from 100 up to 700 PC dual nodes. The interplay between the control and monitoring software with the event readout, event building and the trigger software has been exercised the first time as an integrated system on this large scale. New was also to run algorithms in the online environment for the trigger selection and in the event filter processing tasks on a larger scale. A mechanism has been developed to package the offline software together with the DAQ/HLT software and to distribute it via peer-to-peer software efficiently to this large pc cluster. T...

The Software Architecture of the LHCb High Level Trigger

CERN Multimedia

CERN. Geneva

2012-01-01

The LHCb experiment is a spectrometer dedicated to the study of heavy flavor at the LHC. The rate of proton-proton collisions at the LHC is 15 MHz, but disk space limitations mean that only 3 kHz can be written to tape for offline processing. For this reason the LHCb data acquisition system -- trigger -- plays a key role in selecting signal events and rejecting background. In contrast to previous experiments at hadron colliders like for example CDF or D0, the bulk of the LHCb trigger is implemented in software and deployed on a farm of 20k parallel processing nodes. This system, called the High Level Trigger (HLT) is responsible for reducing the rate from the maximum at which the detector can be read out, 1.1 MHz, to the 3 kHz which can be processed offline,and has 20 ms in which to process and accept/reject each event. In order to minimize systematic uncertainties, the HLT was designed from the outset to reuse the offline reconstruction and selection code, and is based around multiple independent and redunda...

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.

HEP Community White Paper on Software Trigger and Event Reconstruction: Executive Summary

Energy Technology Data Exchange (ETDEWEB)

Albrecht, Johannes; et al.

2018-02-23

Realizing the physics programs of the planned and upgraded high-energy physics (HEP) experiments over the next 10 years will require the HEP community to address a number of challenges in the area of software and computing. For this reason, the HEP software community has engaged in a planning process over the past two years, with the objective of identifying and prioritizing the research and development required to enable the next generation of HEP detectors to fulfill their full physics potential. The aim is to produce a Community White Paper which will describe the community strategy and a roadmap for software and computing research and development in HEP for the 2020s. The topics of event reconstruction and software triggers were considered by a joint working group and are summarized together in this document.

TRIGGER

CERN Multimedia

W. Smith

Level-1 Trigger Hardware and Software The road map for the final commissioning of the level-1 trigger system has been set. The software for the trigger subsystems is being upgraded to run under CERN Scientific Linux 4 (SLC4). There is also a new release for the Trigger Supervisor (TS 1.4), which implies upgrade work by the subsystems. As reported by the CERN group, a campaign to tidy the Trigger Timing and Control (TTC) racks has begun. The machine interface was upgraded by installing the new RF2TTC module, which receives RF signals from LHC Point 4. Two Beam Synchronous Timing (BST) signals, one for each beam, can now be received in CMS. The machine group will define the exact format of the information content shortly. The margin on the locking range of the CMS QPLL is planned for study for different subsystems in the next Global Runs, using a function generator. The TTC software has been successfully tested on SLC4. Some TTC subsystems have already been upgraded to SLC4. The TTCci Trigger Supervisor ...

Check of the accuracy of the relativity theory with atmospheric muon neutrinos from the AMANDA data of the years 2000 to 2003; Ueberpruefung der Genauigkeit der Relativitaetstheorie mit atmosphaerischen Myonneutrinos aus den AMANDA-Daten der Jahre 2000 bis 2003

Energy Technology Data Exchange (ETDEWEB)

Ahrens, J.C.

2006-11-08

Atmospheric neutrinos allow one to test the principles of the Theory of Relativity in particular Lorentz invariance and the equivalence principle. Small deviations from these principles could lead, according to some theories, to detectable neutrino oscillations. Such oscillation effects are analysed in this thesis, using the data collected by the AMANDA detector. The neutrino telescope AMANDA is located at the South Pole and embedded in the Antarctic ice shield at a depth between 1500 m and 2000 m. AMANDA detects muon neutrinos via the Cherenkov light of neutrino induced muons allowing the reconstruction of the original neutrino direction. From the data of the years 2000 to 2003, which contain about seven billion recorded events and which mainly consist of the background of atmospheric muons, a sample of 3401 neutrino induced events has been selected. No indication for alternative oscillation effects has been found. For maximal mixing angles, a lower limit for parameters which violate Lorentz invariance or the equivalence principle could be set to {delta}{beta}(2 vertical stroke {phi} vertical stroke {delta}{gamma}){<=}5.15.10{sup -27}. (orig)

Conception and validation software tools for the level 0 muon trigger of LHCb

International Nuclear Information System (INIS)

Aslanides, E.; Cachemiche, J. P.; Cogan, J.; Duval, P. Y.; Le Gac, R.; Hachon, F.; Leroy, O.; Liotard, P. L.; Marin, F.; Tsaregorodtsev, A.

2009-01-01

The Level-0 muon trigger processor of the LHCb experiment looks for straight particles crossing muon detector and measures their transverse momentum. It processes 40*10 6 proton-proton collisions per second. The tracking uses a road algorithm relying on the projectivity of the muon detector (the logical layout in the 5 muon station is projective in y to the interaction point and it is also projective in x when the bending in the horizontal direction introduced by the magnetic field is ignored). The architecture of the Level-0 muon trigger is complex with a dense network of data interconnections. The design and validation of such an intricate system has only been possible with intense use of software tools for the detector simulation, the modelling of the hardware components behaviour and the validation. A database describing the data-flow is the corner stone between the software and hardware components. (authors)

Time calibration of AMANDA three variations of a theme of T$_{0}$

CERN Document Server

Hanson, K

2002-01-01

The AMANDA-II neutrino telescope currently operating at the South Pole is an array of 677 optical modules (OMs) deployed in the ice at depths between 1200 m and 2300 m beneath the surface. Calibration of the timing offsets of each OM is effected primarily by means of in- ice light pulses transmitted via optical fibers from a surface YAG laser. Discriminator walk, which is significant due to the transmission of electrical signals over 2 km distances, is also calibrated using the YAG laser. Another way to calibrate the timing offsets is to use downgoing cosmic ray muons. This method has the advantages of fuller coverage and year-round availability, i.e., it can be done anytime the detector is taking data. Finally, preliminary results of a technique used to calibrate, with nanosecond precision, the local clocks in "digital optical modules" (DOMs), which digitize and timestamp PMT signals in situ, are presented using DOMs in operation in AMANDA-II. The DOM is part of the baseline design for the planned IceCube de...

Flexible event reconstruction software chains with the ALICE High-Level Trigger

International Nuclear Information System (INIS)

Ram, D; Breitner, T; Szostak, A

2012-01-01

The ALICE High-Level Trigger (HLT) has a large high-performance computing cluster at CERN whose main objective is to perform real-time analysis on the data generated by the ALICE experiment and scale it down to at-most 4GB/sec - which is the current maximum mass-storage bandwidth available. Data-flow in this cluster is controlled by a custom designed software framework. It consists of a set of components which can communicate with each other via a common control interface. The software framework also supports the creation of different configurations based on the detectors participating in the HLT. These configurations define a logical data processing “chain” of detector data-analysis components. Data flows through this software chain in a pipelined fashion so that several events can be processed at the same time. An instance of such a chain can run and manage a few thousand physics analysis and data-flow components. The HLT software and the configuration scheme used in the 2011 heavy-ion runs of ALICE, has been discussed in this contribution.

Drones: Making faster and smarter decisions with software triggers

CERN Multimedia

CERN. Geneva

2018-01-01

Data collection rates in high energy physics (HEP), particularly those at the Large Hadron Collider (LHC) are a continuing challenge and require large amounts of computing power to handle. For example, at LHCb an event rate of 1 MHz is processed in a software-based trigger. The purpose of this trigger is to reduce the output data rate to manageable levels, which amounts to a reduction from 60 GB per second to an output data rate of 0.6 GB per second. Machine learning (ML) is becoming an evermore important tool in the data reduction, be it with the identification of interesting event topologies, or the distinction between individual particle species. For the case of LHCb data-taking, over 600 unique signatures are searched for in parallel in real time, each with its own set of requirements. However, only a handful at present make use of machine learning, despite the large ecosystem. Often the reason for this is the relative difficulty in the application of a preferred ML classifier to the C++/Python combinatio...

Software framework developed for the slice test of the ATLAS endcap muon trigger system

CERN Document Server

Komatsu, S; Ishida, Y; Tanaka, K; Hasuko, K; Kano, H; Matsumoto, Y; Yakamura, Y; Sakamoto, H; Ikeno, M; Nakayoshi, K; Sasaki, O; Yasu, Y; Hasegawa, Y; Totsuka, M; Tsuji, S; Maeno, T; Ichimiya, R; Kurashige, H

2002-01-01

A sliced system test of the ATLAS end cap muon level 1 trigger system has been done in 2001 and 2002 separately. We have developed an own software framework for property and run controls for the slice test in 2001. The system is described in C++ throughout. The multi-PC control system is accomplished using the CORBA system. We have then restructured the software system on top of the ATLAS online software framework, and used this one for the slice test in 2002. In this report we discuss two systems in detail with emphasizing the module property configuration and run control. (8 refs).

Review of Amanda E. Herbert, Female Alliances: Gender, Identity, and Friendship in Early Modern Britain

Directory of Open Access Journals (Sweden)

Angela Rehbein

2015-03-01

Full Text Available Review of Amanda E. Herbert, Female Alliances: Gender, Identity, and Friendship in Early Modern Britain. New Haven: Yale UP, 2014. xi, 256 pages: illustrations; 24 cm. ISBN 978-0-300-17740-4.

An Alternative Flight Software Paradigm: Applying Multivariate Logistic Regression to Sense Trigger Conditions using Inaccurate or Scarce Information

Science.gov (United States)

Smith, Kelly; Gay, Robert; Stachowiak, Susan

2013-01-01

In late 2014, NASA will fly the Orion capsule on a Delta IV-Heavy rocket for the Exploration Flight Test-1 (EFT-1) mission. For EFT-1, the Orion capsule will be flying with a new GPS receiver and new navigation software. Given the experimental nature of the flight, the flight software must be robust to the loss of GPS measurements. Once the high-speed entry is complete, the drogue parachutes must be deployed within the proper conditions to stabilize the vehicle prior to deploying the main parachutes. When GPS is available in nominal operations, the vehicle will deploy the drogue parachutes based on an altitude trigger. However, when GPS is unavailable, the navigated altitude errors become excessively large, driving the need for a backup barometric altimeter to improve altitude knowledge. In order to increase overall robustness, the vehicle also has an alternate method of triggering the parachute deployment sequence based on planet-relative velocity if both the GPS and the barometric altimeter fail. However, this backup trigger results in large altitude errors relative to the targeted altitude. Motivated by this challenge, this paper demonstrates how logistic regression may be employed to semi-automatically generate robust triggers based on statistical analysis. Logistic regression is used as a ground processor pre-flight to develop a statistical classifier. The classifier would then be implemented in flight software and executed in real-time. This technique offers improved performance even in the face of highly inaccurate measurements. Although the logistic regression-based trigger approach will not be implemented within EFT-1 flight software, the methodology can be carried forward for future missions and vehicles

High energy physics experiment triggers and the trustworthiness of software

International Nuclear Information System (INIS)

Nash, T.

1991-10-01

For all the time and frustration that high energy physicists expend interacting with computers, it is surprising that more attention is not paid to the critical role computers play in the science. With large, expensive colliding beam experiments now dependent on complex programs working at startup, questions of reliability -- the trustworthiness of software -- need to be addressed. This issue is most acute in triggers, used to select data to record -- and data to discard -- in the real time environment of an experiment. High level triggers are built on codes that now exceed 2 million source lines -- and for the first time experiments are truly dependent on them. This dependency will increase at the accelerators planned for the new millennium (SSC and LHC), where cost and other pressures will reduce tolerance for first run problems, and the high luminosities will make this on-line data selection essential. A sense of this incipient crisis motivated the unusual juxtaposition to topics in these lectures. 37 refs., 1 fig

Common software for controlling and monitoring the upgraded CMS Level-1 trigger

CERN Document Server

Codispoti, Giuseppe

2017-01-01

The Large Hadron Collider restarted in 2015 with a higher centre-of-mass energy of 13 TeV. The instantaneous luminosity is expected to increase significantly in the coming years. An upgraded Level-1 trigger system was deployed in the CMS experiment in order to maintain the same efficiencies for searches and precision measurements as those achieved in 2012. This system must be controlled and monitored coherently through software, with high operational efficiency.The legacy system was composed of a large number of custom data processor boards; correspondingly, only a small fraction of the software was common between the different subsystems. The upgraded system is composed of a set of general purpose boards, that follow the MicroTCA specification, and transmit data over optical links, resulting in a more homogeneous system. The associated software is based on generic components corresponding to the firmware blocks that are shared across different cards, regardless of the role that the card plays in the system. ...

Implementation of the ATLAS trigger within the multi-threaded software framework AthenaMT

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00225867; The ATLAS collaboration

2017-01-01

We present an implementation of the ATLAS High Level Trigger, HLT, that provides parallel execution of trigger algorithms within the ATLAS multithreaded software framework, AthenaMT. This development will enable the ATLAS HLT to meet future challenges due to the evolution of computing hardware and upgrades of the Large Hadron Collider, LHC, and ATLAS Detector. 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 up to 7.5 times the design value, in 2026 following LHC and ATLAS upgrades. This includes an upgrade of the ATLAS trigger architecture that will result in an increase in the HLT input rate by a factor of 4 to 10 compared to the current maximum rate of 100 kHz. The current ATLAS multiprocess framework, AthenaMP, manages a number of processes that each execute algorithms sequentially for different events. AthenaMT will provide a fully multi-threaded environment that will additionally enable concurrent ...

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...

Search for relativistic magnetic monopoles with the AMANDA-II detector

International Nuclear Information System (INIS)

Wissing, Henrike

2009-01-01

Cherenkov emissions of magnetically charged particles passing through a transparent medium will exceed those of electrically charged particles by several orders of magnitude. The Antarctic Muon And Neutrino Detector Array (AMANDA), a neutrino telescope utilizing the glacial ice at the geographic South Pole as Cherenkov medium, is capable of efficiently detecting relativistic magnetic monopoles that may pass through its sensitive volume. This thesis presents the search for Cherenkov signatures from relativistic magnetic monopoles in data taken with AMANDA during the 2000. No such signal is observed in the data, and the analysis allows to place upper limits on the flux of relativistic magnetic monopoles. The limit obtained for monopoles reaching the detector from below the horizon, i.e., those monopoles that are capable of crossing the Earth, is the most stringent experimental constraint on the flux of magnetic monopoles to date: Dependent on the monopole speed, the flux limit (at 90% confidence level) varies between 3.8 x 10 -17 cm -2 s -1 sr -1 (for monopoles moving at the vacuum speed of light) and 8.8 x 10 -16 cm -2 s -1 sr -1 (for monopoles moving at a speed just above the Cherenkov threshold). The limit obtained for monopoles reaching the detector from above the horizon is less stringent by roughly an order of magnitude, owing to the much larger background from down-going atmospheric muons. This looser limit is valid for a larger class of magnetic monopoles, since the monopole's capability to pass through the Earth is not a requirement. (orig.)

Implementation of the ATLAS trigger within the ATLAS Multi­Threaded Software Framework AthenaMT

CERN Document Server

Wynne, Benjamin; The ATLAS collaboration

2016-01-01

We present an implementation of the ATLAS High Level Trigger that provides parallel execution of trigger algorithms within the ATLAS multi­threaded software framework, AthenaMT. This development will enable the ATLAS High Level Trigger to meet future challenges due to the evolution of computing hardware and upgrades of the Large Hadron Collider, LHC, and ATLAS Detector. During the LHC data­taking period starting in 2021, luminosity will reach up to three times the original design value. Luminosity will increase further, to up to 7.5 times the design value, in 2026 following LHC and ATLAS upgrades. This includes an upgrade of the ATLAS trigger architecture that will result in an increase in the High Level Trigger input rate by a factor of 4 to 10 compared to the current maximum rate of 100 kHz. The current ATLAS multiprocess framework, AthenaMP, manages a number of processes that process events independently, executing algorithms sequentially in each process. AthenaMT will provide a fully multi­threaded env...

The electromagnetic shower library for the Stockholm AMANDA Monte Carlo program

International Nuclear Information System (INIS)

Sun Qin.

1996-05-01

The Shower Library has been applied in the simulation for the AMANDA experiment which measures up-going muons induced by high energy neutrinos at the South Pole. With a detector measuring Cherenkov radiation in mind, only the information of the Cherenkov photons from the showers were stored in the library in the version of the program described here. The library contains 1000 electromagnetic showers with energies from 0.1 GeV to 100 GeV in steps according to a flat logarithmic distribution. 11 refs, 18 figs

A Software Data Transport Framework for Trigger Applications on Clusters

CERN Document Server

Steinbeck, T M; Tilsner, H; Steinbeck, Timm M.; Lindenstruth, Volker; Tilsner, Heinz

2003-01-01

In the future ALICE heavy ion experiment at CERN's Large Hadron Collider input data rates of up to 25 GB/s have to be handled by the High Level Trigger (HLT) system, which has to scale them down to at most 1.25 GB/s before being written to permanent storage. The HLT system that is being designed to cope with these data rates consists of a large PC cluster, up to the order of a 1000 nodes, connected by a fast network. For the software that will run on these nodes a flexible data transport and distribution software framework has been developed. This framework consists of a set of separate components, that can be connected via a common interface, allowing to construct different configurations for the HLT, that are even changeable at runtime. To ensure a fault-tolerant operation of the HLT, the framework includes a basic fail-over mechanism that will be further expanded in the future, utilizing the runtime reconnection feature of the framework's component interface. First performance tests show very promising res...

Check of the accuracy of the relativity theory with atmospheric muon neutrinos from the AMANDA data of the years 2000 to 2003

International Nuclear Information System (INIS)

Ahrens, J.C.

2006-01-01

Atmospheric neutrinos allow one to test the principles of the Theory of Relativity in particular Lorentz invariance and the equivalence principle. Small deviations from these principles could lead, according to some theories, to detectable neutrino oscillations. Such oscillation effects are analysed in this thesis, using the data collected by the AMANDA detector. The neutrino telescope AMANDA is located at the South Pole and embedded in the Antarctic ice shield at a depth between 1500 m and 2000 m. AMANDA detects muon neutrinos via the Cherenkov light of neutrino induced muons allowing the reconstruction of the original neutrino direction. From the data of the years 2000 to 2003, which contain about seven billion recorded events and which mainly consist of the background of atmospheric muons, a sample of 3401 neutrino induced events has been selected. No indication for alternative oscillation effects has been found. For maximal mixing angles, a lower limit for parameters which violate Lorentz invariance or the equivalence principle could be set to Δβ(2 vertical stroke φ vertical stroke Δγ)≤5.15.10 -27 . (orig)

The Search for Muon Neutrinos from Northern HemisphereGamma-Ray Bursts with AMANDA

Energy Technology Data Exchange (ETDEWEB)

IceCube Collaboration; Klein, Spencer; Achterberg, A.

2007-05-08

We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the Northern Hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. Based on our observations of zero neutrinos during and immediately prior to the GRBs in the dataset, we set the most stringent upper limit on muon neutrino emission correlated with gamma-ray bursts. Assuming a Waxman-Bahcall spectrum and incorporating all systematic uncertainties, our flux upper limit has a normalization at 1 PeV of E{sup 2}{Phi}{sub {nu}} {le} 6.0 x 10{sup -9} GeV cm{sup -2}s{sup -1}sr{sup -1}, with 90% of the events expected within the energy range of {approx}10 TeV to {approx}3 PeV. The impact of this limit on several theoretical models of GRBs is discussed, as well as the future potential for detection of GRBs by next generation neutrino telescopes. Finally, we briefly describe several modifications to this analysis in order to apply it to other types of transient point sources.

Set up and programming of an ALICE Time-Of-Flight trigger facility and software implementation for its Quality Assurance (QA) during LHC Run 2

CERN Document Server

Toschi, Francesco

2016-01-01

The Cosmic and Topology Trigger Module (CTTM) is the main component of a trigger based on the ALICE TOF detector. Taking advantage of the TOF fast response, this VME board implements the trigger logic and delivers several L0 trigger outputs, used since Run 1, to provide cosmic triggers and rare triggers in pp, p+Pb and Pb+Pb data taking. Due to TOF DCS architectural change of the PCs controlling the CTTM (from 32 bits to 64 bits) it is mandatory to upgrade the software related to the CTTM including the code programming the FPGA firmware. A dedicated CTTM board will be installed in a CERN lab (Meyrin site), with the aim of recreating the electronics chain of the TOF trigger, to get a comfortable porting of the code to the 64 bit environment. The project proposed to the summer student is the setting up of the CTTM and the porting of the software. Moreover, in order to monitor the CTTM Trigger board during the real data taking, the implementation of a new Quality Assurance (QA) code is also crucial, together wit...

TRIGGER

CERN Multimedia

Wesley Smith

Level-1 Trigger Hardware and Software The trigger synchronization procedures for running with cosmic muons and operating with the LHC were reviewed during the May electronics week. Firmware maintenance issues were also reviewed. Link tests between the new ECAL endcap trigger concentrator cards (TCC48) and the Regional Calorimeter Trigger have been performed. Firmware for the energy sum triggers and an upgraded tau trigger of the Global Calorimeter Triggers has been developed and is under test. The optical fiber receiver boards for the Track-Finder trigger theta links of the DT chambers are now all installed. The RPC trigger is being made more robust by additional chamber and cable shielding and also by firmware upgrades. For the CSC’s the front-end and trigger motherboard firmware have been updated. New RPC patterns and DT/CSC lookup tables taking into account phi asymmetries in the magnetic field configuration are under study. The motherboard for the new pipeline synchronizer of the Global Trigg...

TRIGGER

CERN Multimedia

Wesley Smith

Level-1 Trigger Hardware and Software The hardware of the trigger components has been mostly finished. The ECAL Endcap Trigger Concentrator Cards (TCC) are in production while Barrel TCC firmware has been upgraded, and the Trigger Primitives can now be stored by the Data Concentrator Card for readout by the DAQ. The Regional Calorimeter Trigger (RCT) system is complete, and the timing is being finalized. All 502 HCAL trigger links to RCT run without error. The HCAL muon trigger timing has been equalized with DT, RPC, CSC and ECAL. The hardware and firmware for the Global Calorimeter Trigger (GCT) jet triggers are being commissioned and data from these triggers is available for readout. The GCT energy sums from rings of trigger towers around the beam pipe beam have been changed to include two rings from both sides. The firmware for Drift Tube Track Finder, Barrel Sorter and Wedge Sorter has been upgraded, and the synchronization of the DT trigger is satisfactory. The CSC local trigger has operated flawlessly u...

Concept of the CMS Trigger Supervisor

CERN Document Server

Magrans de Abril, Ildefons; Varela, Joao

2006-01-01

The Trigger Supervisor is an online software system designed for the CMS experiment at CERN. Its purpose is to provide a framework to set up, test, operate and monitor the trigger components on one hand and to manage their interplay and the information exchange with the run control part of the data acquisition system on the other. The Trigger Supervisor is conceived to provide a simple and homogeneous client interface to the online software infrastructure of the trigger subsystems. This document specifies the functional and non-functional requirements, design and operational details, and the components that will be delivered in order to facilitate a smooth integration of the trigger software in the context of CMS.

TRIGGER

CERN Multimedia

Wesley Smith

Level-1 Trigger Hardware and Software The production of the trigger hardware is now basically finished, and in time for the turn-on of the LHC. The last boards produced are the Trigger Concentrator Cards for the ECAL Endcaps (TCC-EE). After the recent installation of the four EE Dees, the TCC-EE prototypes were used for their commissioning. Production boards are arriving and are being tested continuously, with the last ones expected in November. The Regional Calorimeter Trigger hardware is fully integrated after installation of the last EE cables. Pattern tests from the HCAL up to the GCT have been performed successfully. The HCAL triggers are fully operational, including the connection of the HCAL-outer and forward-HCAL (HO/HF) technical triggers to the Global Trigger. The HCAL Trigger and Readout (HTR) board firmware has been updated to permit recording of the tower “feature bit” in the data. The Global Calorimeter Trigger hardware is installed, but some firmware developments are still n...

Practitioner Profile: An Interview With Amanda Mills

Directory of Open Access Journals (Sweden)

Amanda Mills

2012-01-01

Full Text Available For more than 25 years, Amanda Mills has been working with arts organizations across Canada and with artists of all kinds to assist them in achieving financial sanity. She has taught business management at the University of Victoria and has prepared thousands of tax returns for writers, visual artists, choreographers, actors, filmmakers, broadcasters, and creative entrepreneurs. Ten years ago, bringing together her work on trauma, with twenty years of business management, Mills founded Loose Change Financial Therapy – the place where money and feelings meet. Mills has presented Loose Change workshops for social workers, teachers, psychotherapists, artists, anti-poverty activists, sex trade workers, women’s groups, and the general public.  She has been a guest on major Canadian radio and television broadcasts and profiled in many major Canadian newspapers and periodicals. Mills is also a crisis counselor and co-wrote a bestselling book on recovering from trauma. A tax professional and business manager, she is certified as a financial counselor under the Bankruptcy and Insolvency Act. Mills is also currently completing a certificate in mediation.

TRIGGER

CERN Multimedia

by Wesley Smith

2010-01-01

Level-1 Trigger Hardware and Software The overall status of the L1 trigger has been excellent and the running efficiency has been high during physics fills. The timing is good to about 1%. The fine-tuning of the time synchronization of muon triggers is ongoing and will be completed after more than 10 nb-1 of data have been recorded. The CSC trigger primitive and RPC trigger timing have been refined. A new configuration for the CSC Track Finder featured modified beam halo cuts and improved ghost cancellation logic. More direct control was provided for the DT opto-receivers. New RPC Cosmic Trigger (RBC/TTU) trigger algorithms were enabled for collision runs. There is further work planned during the next technical stop to investigate a few of the links from the ECAL to the Regional Calorimeter Trigger (RCT). New firmware and a new configuration to handle trigger rate spikes in the ECAL barrel are also being tested. A board newly developed by the tracker group (ReTRI) has been installed and activated to block re...

Reliability model analysis and primary experimental evaluation of laser triggered pulse trigger

International Nuclear Information System (INIS)

Chen Debiao; Yang Xinglin; Li Yuan; Li Jin

2012-01-01

High performance pulse trigger can enhance performance and stability of the PPS. It is necessary to evaluate the reliability of the LTGS pulse trigger, so we establish the reliability analysis model of this pulse trigger based on CARMES software, the reliability evaluation is accord with the statistical results. (authors)

TRIGGER

CERN Multimedia

W. Smith

2010-01-01

Level-1 Trigger Hardware and Software The Level-1 Trigger hardware has performed well during both the recent proton-proton and heavy ion running. Efforts were made to improve the visibility and handling of alarms and warnings. The tracker ReTRI boards that prevent fixed frequencies of Level-1 Triggers are now configured through the Trigger Supervisor. The Global Calorimeter Trigger (GCT) team has introduced a buffer cleanup procedure at stops and a reset of the QPLL during configuring to ensure recalibration in case of a switch from the LHC clock to the local clock. A device to test the cables between the Regional Calorimeter Trigger and the GCT has been manufactured. A wrong charge bit was fixed in the CSC Trigger. The ECAL group is improving crystal masking and spike suppression in the trigger primitives. New firmware for the Drift Tube Track Finder (DTTF) sorters was developed to improve fake track tagging and sorting. Zero suppression was implemented in the DT Sector Collector readout. The track finder b...

TRIGGER

CERN Multimedia

W. Smith

At the March meeting, the CMS trigger group reported on progress in production, tests in the Electronics Integration Center (EIC) in Prevessin 904, progress on trigger installation in the underground counting room at point 5, USC55, the program of trigger pattern tests and vertical slice tests and planning for the Global Runs starting this summer. The trigger group is engaged in the final stages of production testing, systems integration, and software and firmware development. Most systems are delivering final tested electronics to CERN. The installation in USC55 is underway and integration testing is in full swing. A program of orderly connection and checkout with subsystems and central systems has been developed. This program includes a series of vertical subsystem slice tests providing validation of a portion of each subsystem from front-end electronics through the trigger and DAQ to data captured and stored. After full checkout, trigger subsystems will be then operated in the CMS Global Runs. Continuous...

TRIGGER

CERN Multimedia

Wesley Smith

2011-01-01

Level-1 Trigger Hardware and Software New Forward Scintillating Counters (FSC) for rapidity gap measurements have been installed and integrated into the Trigger recently. For the Global Muon Trigger, tuning of quality criteria has led to improvements in muon trigger efficiencies. Several subsystems have started campaigns to increase spares by recovering boards or producing new ones. The barrel muon sector collector test system has been reactivated, new η track finder boards are in production, and φ track finder boards are under revision. In the CSC track finder, an η asymmetry problem has been corrected. New pT look-up tables have also improved efficiency. RPC patterns were changed from four out of six coincident layers to three out of six in the barrel, which led to a significant increase in efficiency. A new PAC firmware to trigger on heavy stable charged particles allows looking for chamber hit coincidences in two consecutive bunch-crossings. The redesign of the L1 Trigger Emulator...

TRIGGER

CERN Multimedia

W. Smith from contributions of C. Leonidopoulos, I. Mikulec, J. Varela and C. Wulz.

Level-1 Trigger Hardware and Software Over the past few months, the Level-1 trigger has successfully recorded data with cosmic rays over long continuous stretches as well as LHC splash events, beam halo, and collision events. The L1 trigger hardware, firmware, synchronization, performance and readiness for beam operation were reviewed in October. All L1 trigger hardware is now installed at Point 5, and most of it is completely commissioned. While the barrel ECAL Trigger Concentrator Cards are fully operational, the recently delivered endcap ECAL TCC system is still being commissioned. For most systems there is a sufficient number of spares available, but for a few systems additional reserve modules are needed. It was decided to increase the overall L1 latency by three bunch crossings to increase the safety margin for trigger timing adjustments. In order for CMS to continue data taking during LHC frequency ramps, the clock distribution tree needs to be reset. The procedures for this have been tested. A repl...

SWATCH Common software for controlling and monitoring the upgraded CMS Level-1 trigger

CERN Document Server

Lazaridis, Christos; Bunkowski, Karol; Codispoti, Giuseppe; Dirkx, Glenn; Ghabrous Larrea, Carlos; Lingemann, Joschka; Kreczko, Lukasz; Thea, Alessandro; Williams, Tom

2017-01-01

The Large Hadron Collider at CERN restarted in 2015 with a higher centre-of-mass energy of 13 TeV. The instantaneous luminosity is expected to increase significantly in the coming years. An upgraded Level-1 trigger system is being deployed in the CMS experiment in order to maintain the same efficiencies for searches and precision measurements as those achieved in the previous run. This system must be controlled and monitored coherently through software, with high operational efficiency.The legacy system is composed of approximately 4000 data processor boards, of several custom application-specific designs. These boards are organised into several subsystems; each subsystem receives data from different detector systems (calorimeters, barrel/endcap muon detectors), or with differing granularity. These boards have been controlled and monitored by a medium-sized distributed system of over 40 computers and 200 processes. Only a small fraction of the control and monitoring software was common between the different s...

Manlighet, mod och moral: Amanda Kerfstedts Carl Bergs skoltid

Directory of Open Access Journals (Sweden)

Andersson, Maria

2011-03-01

Full Text Available Amanda Kerfstedt’s ”Carl Bergs skoltid” describes a boy’s journey to manhood in late 19th century Sweden. This article pertains that the text contrasts an ideal of masculinity based on physical strength with an ideal emphasizing morality. Although a true man, as described in the story, is expected to be strong as well as righteous, the moral component is the most important. The text shows that courage and force, which are not checked by a sense of ethics, may turn into brutality and abuse of power. Different types of masculinity are compared in ”Carl Bergs skoltid” but masculinity is also defined in relation to ideas about femininity. The association with women is utilized to stress a lack of courage in men as well as to redefine a masculine ideal that has focused too much on physical prowess instead of strength of character.

TRIGGER

CERN Multimedia

Wesley Smith

Level-1 Trigger Hardware and Software The final parts of the Level-1 trigger hardware are now being put in place. For the ECAL endcaps, more than half of the Trigger Concentrator Cards for the ECAL Endcap (TCC-EE) are now available at CERN, such that one complete endcap can be covered. The Global Trigger now correctly handles ECAL calibration sequences, without being influenced by backpressure. The Regional Calorimeter Trigger (RCT) hardware is complete and working in USC55. Intra-crate tests of all 18 RCT crates and the Global Calorimeter Trigger (GCT) are regularly taking place. Pattern tests have successfully captured data from HCAL through RCT to the GCT Source Cards. HB/HE trigger data are being compared with emulator results to track down the very few remaining hardware problems. The treatment of hot and dead cells, including their recording in the database, has been defined. For the GCT, excellent agreement between the emulator and data has been achieved for jets and HF ET sums. There is still som...

TRIGGER

CERN Multimedia

W. Smith

Level-1 Trigger Hardware and Software The trigger system has been constantly in use in cosmic and commissioning data taking periods. During CRAFT running it delivered 300 million muon and calorimeter triggers to CMS. It has performed stably and reliably. During the abort gaps it has also provided laser and other calibration triggers. Timing issues, namely synchronization and latency issues, have been solved. About half of the Trigger Concentrator Cards for the ECAL Endcap (TCC-EE) are installed, and the firmware is being worked on. The production of the other half has started. The HCAL Trigger and Readout (HTR) card firmware has been updated, and new features such as fast parallel zero-suppression have been included. Repairs of drift tube (DT) trigger mini-crates, optical links and receivers of sector collectors are under way and have been completed on YB0. New firmware for the optical receivers of the theta links to the drift tube track finder is being installed. In parallel, tests with new eta track finde...

Using modern software tools to design, simulate and test a Level 1 trigger sub-system for the D Zero Detector

International Nuclear Information System (INIS)

Angstadt, R.; Borcherding, F.; Johnson, M.E.; Moreira, L.

1995-06-01

This paper describes a system which uses a commercial spreadsheet program and commercial hardware on an IBM PC to develop and test a track finding system for the D Zero Level 1 scintillating Fiber Trigger. The trigger system resides in a VME crate. This system allows the user to generate test input, write the pattern to the hardware simulate the results in software, read the hardware result: compare the results and inform the user of any differences

TRIGGER

CERN Multimedia

by Wesley Smith

2011-01-01

Level-1 Trigger Hardware and Software After the winter shutdown minor hardware problems in several subsystems appeared and were corrected. A reassessment of the overall latency has been made. In the TTC system shorter cables between TTCci and TTCex have been installed, which saved one bunch crossing, but which may have required an adjustment of the RPC timing. In order to tackle Pixel out-of-syncs without influencing other subsystems, a special hardware/firmware re-sync protocol has been introduced in the Global Trigger. The link between the Global Calorimeter Trigger and the Global Trigger with the new optical Global Trigger Interface and optical receiver daughterboards has been successfully tested in the Electronics Integration Centre in building 904. New firmware in the GCT now allows a setting to remove the HF towers from energy sums. The HF sleeves have been replaced, which should lead to reduced rates of anomalous signals, which may allow their inclusion after this is validated. For ECAL, improvements i...

TRIGGER

CERN Multimedia

W. Smith from contributions of C. Leonidopoulos

2010-01-01

Level-1 Trigger Hardware and Software Since nearly all of the Level-1 (L1) Trigger hardware at Point 5 has been commissioned, activities during the past months focused on the fine-tuning of synchronization, particularly for the ECAL and the CSC systems, on firmware upgrades and on improving trigger operation and monitoring. Periodic resynchronizations or hard resets and a shortened luminosity section interval of 23 seconds were implemented. For the DT sector collectors, an automatic power-off was installed in case of high temperatures, and the monitoring capabilities of the opto-receivers and the mini-crates were enhanced. The DTTF and the CSCTF now have improved memory lookup tables. The HCAL trigger primitive logic implemented a new algorithm providing better stability of the energy measurement in the presence of any phase misalignment. For the Global Calorimeter Trigger, additional Source Cards have been manufactured and tested. Testing of the new tau, missing ET and missing HT algorithms is underw...

The ATLAS Muon and Tau Trigger

CERN Document Server

Dell'Asta, L; The ATLAS collaboration

2013-01-01

[Muon] The ATLAS experiment at CERN's Large Hadron Collider (LHC) deploys a three-levels processing scheme for the trigger system. The level-1 muon trigger system gets its input from fast muon trigger detectors. Fast sector logic boards select muon candidates, which are passed via an interface board to the central trigger processor and then to the High Level Trigger (HLT). The muon HLT is purely software based and encompasses a level-2 (L2) trigger followed by an event filter (EF) for a staged trigger approach. It has access to the data of the precision muon detectors and other detector elements to refine the muon hypothesis. Trigger-specific algorithms were developed and are used for the L2 to increase processing speed for instance by making use of look-up tables and simpler algorithms, while the EF muon triggers mostly benefit from offline reconstruction software to obtain most precise determination of the track parameters. There are two algorithms with different approaches, namely inside-out and outside-in...

TRIGGER

CERN Multimedia

W. Smith

2011-01-01

Level-1 Trigger Hardware and Software Overall the L1 trigger hardware has been running very smoothly during the last months of proton running. Modifications for the heavy-ion run have been made where necessary. The maximal design rate of 100 kHz can be sustained without problems. All L1 latencies have been rechecked. The recently installed Forward Scintillating Counters (FSC) are being used in the heavy ion run. The ZDC scintillators have been dismantled, but the calorimeter itself remains. We now send the L1 accept signal and other control signals to TOTEM. Trigger cables from TOTEM to CMS will be installed during the Christmas shutdown, so that the TOTEM data can be fully integrated within the CMS readout. New beam gas triggers have been developed, since the BSC-based trigger is no longer usable at high luminosities. In particular, a special BPTX signal is used after a quiet period with no collisions. There is an ongoing campaign to provide enough spare modules for the different subsystems. For example...

TRIGGER

CERN Multimedia

W. Smith

At the December meeting, the CMS trigger group reported on progress in production, tests in the Electronics Integration Center (EIC) in Prevessin 904, progress on trigger installation in the underground counting room at point 5, USC55, and results from the Magnet Test and Cosmic Challenge (MTCC) phase II. The trigger group is engaged in the final stages of production testing, systems integration, and software and firmware development. Most systems are delivering final tested electronics to CERN. The installation in USC55 is underway and moving towards integration testing. A program of orderly connection and checkout with subsystems and central systems has been developed. This program includes a series of vertical subsystem slice tests providing validation of a portion of each subsystem from front-end electronics through the trigger and DAQ to data captured and stored. This is combined with operations and testing without beam that will continue until startup. The plans for start-up, pilot and early running tri...

Communication between Trigger/DAQ and DCS in ATLAS

International Nuclear Information System (INIS)

Burckhart, H.; Jones, R.; Hart, R.; Khomoutnikov, V.; Ryabov, Y.

2001-01-01

Within the ATLAS experiment Trigger/DAQ and DCS are both logically and physically separated. Nevertheless there is a need to communicate. The initial problem definition and analysis suggested three subsystems the Trigger/DAQ DCS Communication (DDC) project should support the ability to: 1. exchange data between Trigger/DAQ and DCS; 2. send alarm messages from DCS to Trigger/DAQ; 3. issue commands to DCS from Trigger/DAQ. Each subsystem is developed and implemented independently using a common software infrastructure. Among the various subsystems of the ATLAS Trigger/DAQ the Online is responsible for the control and configuration. It is the glue connecting the different systems such as data flow, level 1 and high-level triggers. The DDC uses the various Online components as an interface point on the Trigger/DAQ side with the PVSS II SCADA system on the DCS side and addresses issues such as partitioning, time stamps, event numbers, hierarchy, authorization and security. PVSS II is a commercial product chosen by CERN to be the SCADA system for all LHC experiments. Its API provides full access to its database, which is sufficient to implement the 3 subsystems of the DDC software. The DDC project adopted the Online Software Process, which recommends a basic software life-cycle: problem statement, analysis, design, implementation and testing. Each phase results in a corresponding document or in the case of the implementation and testing, a piece of code. Inspection and review take a major role in the Online software process. The DDC documents have been inspected to detect flaws and resulted in a improved quality. A first prototype of the DDC is ready and foreseen to be used at the test-beam during summer 2001

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...

Search for atmospheric muon-neutrinos and extraterrestric neutrino point sources in the 1997 AMANDA-B10 data

International Nuclear Information System (INIS)

Biron von Curland, A.

2002-07-01

The young field of high energy neutrino astronomy can be motivated by the search for the origin of the charged cosmic rays. Large astrophysical objects like AGNs or supernova remnants are candidates to accelerate hadrons which then can interact to eventually produce high energy neutrinos. Neutrino-induced muons can be detected via their emission of Cherenkov light in large neutrino telescopes like AMANDA. More than 10 9 atmospheric muon events and approximately 5000 atmospheric neutrino events were registered by AMANDA-B10 in 1997. Out of these, 223 atmospheric neutrino candidate events have been extracted. This data set contains approximately 15 background events. It allows to confirm the expected sensitivity of the detector towards neutrino events. A second set containing 369 (approximately 270 atmospheric neutrino events and 100 atmospheric muon events) was used to search for extraterrestrial neutrino point sources. Neither a binned search, nor a cluster search, nor a search for preselected sources gave indications for the existence of a strong neutrino point source. Based on this result, flux limits were derived. Assuming E ν -2 spectra, typical flux limits for selected sources of the order of Φ μ limit ∝ 10 -14 cm -2 s -1 for muons and Φ ν limit ∝ 10 -7 cm -2 s -1 for neutrinos have been obtained. (orig.)

Mothers, daughters and midlife (self)-discoveries: gender and aging in the Amanda Cross' Kate Fansler series.

Science.gov (United States)

Domínguez-Rué, Emma

2012-12-01

In the same way that many aspects of gender cannot be understood aside from their relationship to race, class, culture, nationality and/or sexuality, the interactions between gender and aging constitute an interesting field for academic research, without which we cannot gain full insight into the complex and multi-faceted nature of gender studies. Although the American writer and Columbia professor Carolyn Gold Heilbrun (1926-2003) is more widely known for her best-selling mystery novels, published under the pseudonym of Amanda Cross, she also authored remarkable pieces of non-fiction in which she asserted her long-standing commitment to feminism, while she also challenged established notions on women and aging and advocated for a reassessment of those negative views. To my mind, the Kate Fansler novels became an instrument to reach a massive audience of female readers who might not have read her non-fiction, but who were perhaps finding it difficult to reach fulfillment as women under patriarchy, especially upon reaching middle age. Taking her essays in feminism and literary criticism as a basis and her later fiction as substantiation to my argument, this paper will try to reveal the ways in which Heilbrun's seemingly more superficial and much more commercial mystery novels as Amanda Cross were used a catalyst that informed her feminist principles while vindicating the need to rethink about issues concerning literary representations of mature women and cultural stereotypes about motherhood. Copyright © 2012 Elsevier Inc. All rights reserved.

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.

Upgrading the Interface and Developer Tools of the Trigger Supervisor Software Framework of the CMS experiment at CERN

CERN Document Server

AUTHOR|(CDS)2097518; Karsmakers, Peter

The Compact Muon Solenoid (CMS) Trigger Supervisor (TS) is a software framework that has been designed to handle the CMS Level-1 trigger setup, configuration and monitoring during data taking as well as all communications with the main run control of CMS. The interface consists of a web-based GUI rendered by a back-end C++ framework (AjaXell) and a front-end JavaScript framework (Dojo). These provide developers with the tools they need to to write their own custom control panels. However, currently there is much frustration with this framework given the age of the Dojo library and the various hacks needed to implement modern use cases. The task at hand is to renew this library and its developer tools, updating it to use the newest standards and technologies, while maintaining full compatibility with legacy code. This document describes the requirements, development process, and changes to this framework that were included in the upgrade from v2.x to v3.x. Keywords: CERN, CMS, L1 Trigger, C++, Polymer, Web Com...

NOMAD Trigger Studies

International Nuclear Information System (INIS)

Varvell, K.

1995-01-01

The author reports on the status of an offline study of the NOMAD triggers, which has several motivations. Of primary importance is to demonstrate, using offline information recorded by the individual subdetectors comprising NOMAD, that the online trigger system is functioning as expected. Such an investigation serves to complement the extensive monitoring which is already carried out online. More specific to the needs of the offline software and analysis, the reconstruction of tracks and vertices in the detector requires some knowledge of the time at which the trigger has occurred, in order to locate relevant hits in the drift chambers and muon chambers in particular. The fact that the different triggers allowed by the MIOTRINO board take varying times to form complicates this task. An offline trigger algorithm may serve as a tool to shed light on situations where the online trigger status bits have not been recorded correctly, as happens in a small number of cases, or as an aid to studies with the aim of further refinement of the online triggers themselves

Trigger Menu-aware Monitoring for the ATLAS experiment

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00441925; The ATLAS collaboration

2017-01-01

Changes in the trigger menu, the online algorithmic event-selection of the ATLAS experiment at the LHC, are followed by adjustments to the ATLAS trigger monitoring systems. During Run 1, and so far in Run 2, ATLAS has deployed monitoring updates with the installation of new software releases at Tier-0, the first level of the ATLAS computing grid. Having to wait for a new software release to be installed at Tier-0, in order to update ATLAS offline trigger monitoring configurations, results in a lag with respect to the modification of the trigger menu. We present the design and implementation of a `trigger menu-aware' monitoring system that aims to simplify the ATLAS operational workflows by allowing monitoring configuration changes to be made at the Tier-0 site by utilising an Oracle SQL database.

The D0 calorimeter trigger

International Nuclear Information System (INIS)

Guida, J.

1992-12-01

The D0 calorimeter trigger system consists of many levels to make physics motivated trigger decisions. The Level-1 trigger uses hardware techniques to reduce the trigger rate from ∼ 100kHz to 200Hz. It forms sums of electromagnetic and hadronic energy, globally and in towers, along with finding the missing transverse energy. A minimum energy is set on these energy sums to pass the event. The Level-2 trigger is a set of software filters, operating in a parallel-processing microvax farm which further reduces the trigger rate to a few Hertz. These filters will reject events which lack electron candidates, jet candidates, or missing transverse energy in the event. The performance of these triggers during the early running of the D0 detector will also be discussed

Detection of coronary artery calcification with non triggered computed tomography of the chest

Energy Technology Data Exchange (ETDEWEB)

Pelandré, Gustavo Lemos; Sanches, Nathália Martins Pereira, E-mail: gustavo.pelandre@ufsc.br [Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC (Brazil); Nacif, Marcelo Souto [Universidade Federal Fluminense (UFF), Niterói, RJ (Brazil); Marchiori, Edson [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

2018-01-15

Objective: To evaluate the accuracy of visual analysis and of the coronary artery calcium (CAC) score in non triggered computed tomography (CT), in comparison with that of the CAC score in electrocardiogram-triggered CT, in identifying coronary calcification. Materials and methods: A total of 174 patients for whom CT was indicated for CAC scoring underwent non triggered and triggered CT in a 64-channel multislice scanner, in a single session without a change in position. The images were interpreted by a radiologist with seven years of experience in thoracic and cardiovascular radiology. The measurement of coronary calcium was carried out by three methods: CAC score with dedicated software in non triggered CT, CAC score with dedicated software in triggered CT, and visual analysis without dedicated software in non triggered CT. Results: In non triggered CT, the CAC score presented an accuracy of 95.98% (95% CI: 91.93 - 98.04). The visual analysis showed an accuracy of 97.13% (95% CI: 93.45 - 98.77). Conclusion: Non triggered CT showed excellent accuracy in the identification and exclusion of coronary calcification, either the CAC score was determined with dedicated software or through visual analysis. (author)

Performance and development plans for the Inner Detector trigger algorithms at ATLAS

International Nuclear Information System (INIS)

Martin-Haugh, Stewart

2014-01-01

A description of the algorithms and the performance of the ATLAS Inner Detector trigger for LHC Run 1 are presented, as well as prospects for a redesign of the tracking algorithms in Run 2. The Inner Detector trigger algorithms are vital for many trigger signatures at ATLAS. The performance of the algorithms for electrons is presented. The ATLAS trigger software will be restructured from two software levels into a single stage which poses a big challenge for the trigger algorithms in terms of execution time and maintaining the physics performance. Expected future improvements in the timing and efficiencies of the Inner Detector triggers are discussed, utilising the planned merging of the current two stages of the ATLAS trigger.

Tracking at High Level Trigger in CMS

CERN Document Server

Tosi, Mia

2016-01-01

The trigger systems of the LHC detectors play a crucial role in determining the physics capabili- ties of the experiments. A reduction of several orders of magnitude of the event rate is needed to reach values compatible with detector readout, offline storage and analysis capability. The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger (L1T), implemented on custom-designed electronics, and the High Level Trigger (HLT), a stream- lined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a trade-off between the complexity of the algorithms, the sustainable out- put rate, and the selection efficiency. With the computing power available during the 2012 data taking the maximum reconstruction time at HLT was about 200 ms per event, at the nominal L1T rate of 100 kHz. Track reconstruction algorithms are widely used in the HLT, for the reconstruction of the physics objects as well as in the identification of b-jets and ...

Upgrade trigger & reconstruction strategy: 2017 milestone

CERN Document Server

Albrecht, Johannes; Campora Perez, Daniel Hugo; Cattaneo, Marco; Marco, Clemencic; Couturier, Ben; Dziurda, Agnieszka; Fitzpatrick, Conor; Fontana, Marianna; Grillo, Lucia; Hasse, Christoph; Hill, Donal; Jones, Christopher Rob; Lemaitre, Florian; Lupton, Olli; Matev, Rosen; Pearce, Alex; Polci, Francesco; Promberger, Laura; Ponce, Sebastien; Quagliani, Renato; Raven, Gerhard; Sciascia, Barbara; Schiller, Manuel Tobias; Stahl, Sascha; Szymanski, Maciej Pawel; Chefdeville, Maximilien

2018-01-01

The LHCb collaboration is currently preparing an update of the experiment to take data in Run 3 of the LHC. The dominant feature of this upgrade is a trigger-less readout of the full detector followed by a full software trigger. To make optimal use of the collected data, the events are reconstructed at the inelastic collision rate of 30 MHz. This document presents the baseline trigger and reconstruction strategy as of the end of 2017.

CMS Trigger Performance

CERN Document Server

Donato, Silvio

2017-01-01

During its second run of operation (Run 2) which started in 2015, the LHC will deliver a peak instantaneous luminosity that may reach $2 \\cdot 10^{34}$ cm$^{-2}$s$^{-1}$ with an average pile-up of about 55, far larger than the design value. Under these conditions, the online event selection is a very challenging task. In CMS, it is realized by a two-level trigger system the Level-1 (L1) Trigger, implemented in custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the offline reconstruction software running on a computer farm. In order to face this challenge, the L1 trigger has been through a major upgrade compared to Run 1, whereby all electronic boards of the system have been replaced, allowing more sophisticated algorithms to be run online. Its last stage, the global trigger, is now able to perform complex selections and to compute high-level quantities, like invariant masses. Likewise, the algorithms that run in the HLT go through big improvements; in particular, new appr...

GPUs for real-time processing in HEP trigger systems

CERN Document Server

Ammendola, R; Deri, L; Fiorini, M; Frezza, O; Lamanna, G; Lo Cicero, F; Lonardo, A; Messina, A; Sozzi, M; Pantaleo, F; Paolucci, Ps; Rossetti, D; Simula, F; Tosoratto, L; Vicini, P

2014-01-01

We describe a pilot project (GAP - GPU Application Project) for the use of GPUs (Graphics processing units) for online triggering applications in High Energy Physics experiments. Two major trends can be identied in the development of trigger and DAQ systems for particle physics experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a fully software data selection system (\\trigger-less"). The innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software not only in high level trigger levels but also in early trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several elds of science, although so far applications have been tailored to the specic strengths of such devices as accelerators in oine computation. With the steady reduction of GPU latencies, and the incre...

Advances in tracking and trigger concepts

International Nuclear Information System (INIS)

Kisel, Ivan

2014-01-01

Increasing beam intensities and input data rates require to rethink the traditional approaches in trigger concepts. At the same time the advanced many-core computer architectures providing new dimensions in programming require to rework the standard methods or to develop new methods of track reconstruction in order to efficiently use parallelism of the computer hardware. As a results a new tendency appears to replace the standard (usually implemented in FPGA) hardware triggers by clusters of computers running software reconstruction and selection algorithms. In addition that makes possible unification of the offline and on-line data processing and analysis in one software package running on a heterogeneous computer farm

The second level trigger of the L3 experiment. Pt. 2

International Nuclear Information System (INIS)

Beingessner, S.P.; Blaising, J.J.; Chollet-Le Flour, F.; Degre, A.; Dromby, G.; Goy, C.; Lecoq, J.; Morand, R.; Moynot, M.; Perrot, G.; Rosier-Lees, S.; Forconi, G.

1993-07-01

The events recorded by the L3 Data Acquisition System are selected by three levels of trigger. The event filtering performed by software at the second trigger level is described. First coded offline in FORTRAN, the filtering software is microcoded for online execution in a farm of 3 XOP processors operating in a round robin mode. It identifies and rejects background events. Depending on running conditions and trigger type, rejection factors ranging from 45% to 80% are obtained on first level energy, muon and tec triggers. Selection efficiencies greater than 99.95% are achieved. (authors). 14 refs., 3 figs., 2 tabs

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...

Trigger tracking for the LHCb upgrade

CERN Multimedia

Dungs, K

2014-01-01

This poster presents a trigger system for the upgraded LHCb detector, scheduled to begin operation in 2020. The proposed trigger system is implemented entirely in software. We show that track reconstruction of a similar quality to that available in the offline algorithms can be performed on the full inelastic pp-collision rate. A track finding efficiency of 98.8% relative to offline can be achieved for good trigger tracks. The CPU time required for this reconstruction is less than 60% of the available budget.

Trigger and decision processors

International Nuclear Information System (INIS)

Franke, G.

1980-11-01

In recent years there have been many attempts in high energy physics to make trigger and decision processes faster and more sophisticated. This became necessary due to a permanent increase of the number of sensitive detector elements in wire chambers and calorimeters, and in fact it was possible because of the fast developments in integrated circuits technique. In this paper the present situation will be reviewed. The discussion will be mainly focussed upon event filtering by pure software methods and - rather hardware related - microprogrammable processors as well as random access memory triggers. (orig.)

Readout and triggering of the Soudan 2 nucleon decay experiment

International Nuclear Information System (INIS)

Thron, J.L.

1984-01-01

The readout and triggering electronics for the Soudan 2 proton decay detector is presented. Pratically all the electronics is implemented in CMOS. The triggering scheme is highly flexible and software controllable

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...

Tau lepton trigger and identification at CMS in Run-2

CERN Document Server

Davignon, Olivier

2016-01-01

In the context of LHC Run-2, the Compact Muon Solenoid (CMS) detector was upgraded. In particular, the CMS trigger system and particle reconstruction were improved. The CMS experiment implements a sophisticated trigger system composed of a Level-1 trigger, instrumented by custom-designed hardware boards, and software layers called High-Level-Triggers (HLT). A new Level-1 trigger architecture with improved performance has been installed and is now used to maintain the thresholds used in LHC Run-1 in the more challenging conditions experienced during Run-2. Optimized software selection techniques have also been developed at the HLT. The hadronic $\\tau$ reconstruction algorithm has been modified to better account for the $\\pi^0$(s) from $\\tau$ decays. In addition, improvements to discriminators against QCD-induced jets and electrons were also developed. The results of these improvements are presented and the validation of the $\\tau$ identification performance is shown.

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...

The Run-2 ATLAS Trigger System

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00222798; The ATLAS collaboration

2016-01-01

The ATLAS trigger successfully collected collision data during the first run of the LHC between 2009-2013 at different centre-of-mass energies between 900 GeV and 8 TeV. The trigger system consists of a hardware Level-1 and a software-based high level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. In Run-2, the LHC will operate at centre-of-mass energies of 13 and 14 TeV and higher luminosity, resulting in roughly five times higher trigger rates. A brief review of the ATLAS trigger system upgrades that were implemented between Run-1 and Run-2, allowing to cope with the increased trigger rates while maintaining or even improving the efficiency to select physics processes of interest, will be given. This includes changes to the Level-1 calorimeter and muon trigger systems, the introduction of a new Level-1 topological trigger module and the merging of the previously two-level HLT system into a single event filter farm. A ...

ATLAS Jet Trigger Update for the LHC Run II

CERN Document Server

Prince, Sebastien; The ATLAS collaboration

2015-01-01

After the current shutdown, the LHC is about to resume operation for a new data-taking period, when it will operate with increased luminosity, event rate and centre of mass energy. The new conditions will impose more demanding constraints on the ATLAS online trigger reconstruction and selection system. To cope with such increased constraints, the ATLAS High Level Trigger, placed after a first hardware-based Level-1 trigger, has been redesigned by merging two previously separated software-based processing levels. In the new joint processing level, the algorithms run in the same computing nodes, thus sharing resources, minimizing the data transfer from the detector buffers and increasing the algorithm flexibility. The Jet trigger software selects events containing high transverse momentum hadronic jets. It needs optimal jet energy resolution to help rejecting an overwhelming background while retaining good efficiency for interesting jets. In particular, this requires the CPU-intensive reconstruction of tridimen...

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...

The CDF level-3 trigger

International Nuclear Information System (INIS)

Devlin, T.

1993-01-01

The Collider Detector at Fermilab (CDF) has been operating at the Tevatron and collecting data on proton-antiproton interactions with collision rates above 250,000 Hz. Three levels of filtering select events for data logging at a rate of about 4 Hz. The Level 3 trigger provides most of the capabilities of the offline production programs for event reconstruction and physics analysis. The type of physics triggers, application of cuts, and combinations of logical requirements for event selection are controlled at run time by a trigger table using a syntax fully integrated with the Level 1 and Level 2 hardware triggers. The level 3 software operates in 48 RISC/UNIX processors (over 1000 mips) served by four 20-MByte/sec data buses for input, output and control. The system architecture, debugging, code validation, error reporting, analysis capabilities and performance will be described

Tools for Trigger Aware Analyses in ATLAS

CERN Document Server

Krasznahorkay, A; The ATLAS collaboration; Stelzer, J

2010-01-01

In order to search for rare processes, all four LHC experiments have to use advanced triggering methods for selecting and recording the events of interest. At the expected nominal LHC operating conditions only about 0.0005% of the collision events can be kept for physics analysis in ATLAS. Therefore the understanding and evaluation of the trigger performance is one of the most crucial parts of any physics analysis. ATLAS’s first level trigger is composed of custom-built hardware, while the second and third levels are implemented using regular PCs running reconstruction and selection algorithms. Because of this split, accessing the results of the trigger execution for the two stages is different. The complexity of the software trigger presents further difficulties in accessing the trigger data. To make the job of the physicists easier when evaluating the trigger performance, multiple general-use tools are provided by the ATLAS Trigger Analysis Tools group. The TrigDecisionTool, a general tool, is provided to...

Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector

International Nuclear Information System (INIS)

Ahrens, J.; Bai, X.; Barwick, S.W.; Bay, R.C.; Becka, T.; Becker, K.-H.; Bernardini, E.; Bertrand, D.; Binon, F.; Boeser, S.; Botner, O.; Bouchta, A.; Bouhali, O.; Burgess, T.; Carius, S.; Castermans, T.; Chirkin, D.; Conrad, J.; Cooley, J.; Cowen, D.F.; Davour, A.; De Clercq, C.; DeYoung, T.; Desiati, P.; Doksus, P.; Ekstrom, P.; Feser, T.; Gaisser, T.K.; Ganugapati, R.; Gaug, M.; Geenen, H.; Gerhardt, L.; Goldschmidt, A.; Hallgren, A.; Halzen, F.; Hanson, K.; Hardtke, R.; Hauschildt, T.; Hellwig, M.; Herquet, P.; Hill, G.C.; Hulth, P.O.; Hughey, B.; Hultqvist, K.; Hundertmark, S.; Jacobsen, J.; Karle, A.; Kuehn, K.; Kim, J.; Kopke, L.; Kowalski, M.; Lamoureux, J.I.; Leich, H.; Leuthold, M.; Lindahl, P.; Liubarsky, I.; Madsen, J.; Mandli, K.; Marciniewski, P.; Matis, H.S.; McParland, C.P.; Messarius, T.; Miller, T.C.; Minaeva, Y.; Miocinovic, P.; Mock, P.C.; Morse, R.; Neunhoffer, T.; Niessen, P.; Nygren, D.R.; Ogelman, H.; Olbrechts, P.; Perez de los Heros, C.; Pohl, A.C.; Porrata, R.; Price, P.B.; Przybylski, G.T.; Rawlins, K.; Resconi, E.; Rhode, W.; Ribordy, M.; Richter, S.; Rodriguez Martino, J.; Romenesko, P.; Ross, D.; Sander, H.-G.; Schlenstedt, S.; Schinarakis, K.; Schmidt, T.; Schneider, D.; Schwarz, R.; Silvestri, A.; Solarz, M.; Stamatikos, M.; Spiczak, G.M.; Spiering, C.; Steele, D.; Steffen, P.; Stokstad, R.G.; Sulanke, K.-H.; Taboada, I.; Tilav, S.; Wagner, W.; Walck, C.; Wang, Y.-R.; Wiebusch, C.H.; Wiedemann, C.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Wu, W.; Yodh, G.; Young, S.

2003-01-01

Data from the AMANDA-B10 detector taken during the austral winter of 1997 have been searched for a diffuse flux of high energy extraterrestrial muon-neutrinos, as predicted from, e.g., the sum of all active galaxies in the universe. This search yielded no excess events above those expected from the background atmospheric neutrinos, leading to upper limits on the extraterrestrial neutrino flux. For an assumed E -2 spectrum, a 90 percent classical confidence level upper limit has been placed at a level E 2 Phi(E) = 8.4 x 10 -7 GeV cm -2 s -1 1 sr -1 (for a predominant neutrino energy range 6-1000 TeV) which is the most restrictive bound placed by any neutrino detector. When specific predicted spectral forms are considered, it is found that some are excluded

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...

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...

The upgrade of the LHCb trigger system

CERN Document Server

INSPIRE-00259834; Fitzpatrick, C.; Gligorov, V.; Raven, G.

2014-10-20

The LHCb experiment will operate at a luminosity of $2\\times10^{33}$ cm$^{-2}$s$^{-1}$ during LHC Run 3. At this rate the present readout and hardware Level-0 trigger become a limitation, especially for fully hadronic final states. In order to maintain a high signal efficiency the upgraded LHCb detector will deploy two novel concepts: a triggerless readout and a full software trigger.

The ATLAS Electron and Photon Trigger

CERN Document Server

Jones, Samuel David; The ATLAS collaboration

2017-01-01

Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for signal selection in a wide variety of ATLAS physics analyses to study Standard Model processes and to search for new phenomena. Final states including leptons and photons had, for example, an important role in the discovery and measurement of the Higgs boson. Dedicated triggers are also used to collect data for calibration, efficiency and fake rate measurements. The ATLAS trigger system is divided in a hardware-based Level-1 trigger and a software-based high-level trigger, both of which were upgraded during the LHC shutdown in preparation for Run-2 operation. To cope with the increasing luminosity and more challenging pile-up conditions at a center-of-mass energy of 13 TeV, the trigger selections at each level are optimized to control the rates and keep efficiencies high. To achieve this goal multivariate analysis techniques are used. The ATLAS electron and photon triggers and their performance with Run 2 dat...

The ATLAS Electron and Photon Trigger

CERN Document Server

Jones, Samuel David; The ATLAS collaboration

2018-01-01

Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for signal selection in a wide variety of ATLAS physics analyses to study Standard Model processes and to search for new phenomena. Final states including leptons and photons had, for example, an important role in the discovery and measurement of the Higgs boson. Dedicated triggers are also used to collect data for calibration, efficiency and fake rate measurements. The ATLAS trigger system is divided in a hardware-based Level-1 trigger and a software-based high-level trigger, both of which were upgraded during the LHC shutdown in preparation for Run-2 operation. To cope with the increasing luminosity and more challenging pile-up conditions at a center-of-mass energy of 13 TeV, the trigger selections at each level are optimized to control the rates and keep efficiencies high. To achieve this goal multivariate analysis techniques are used. The ATLAS electron and photon triggers and their performance with Run 2 dat...

The architecture of the CMS Level-1 Trigger Control and Monitoring System using UML

International Nuclear Information System (INIS)

Magrans de Abril, Marc; Ghabrous Larrea, Carlos; Lazaridis, Christos; Da Rocha Melo, Jose L; Hammer, Josef; Hartl, Christian

2011-01-01

The architecture of the Compact Muon Solenoid (CMS) Level-1 Trigger Control and Monitoring software system is presented. This system has been installed and commissioned on the trigger online computers and is currently used for data taking. It has been designed to handle the trigger configuration and monitoring during data taking as well as all communications with the main run control of CMS. Furthermore its design has foreseen the provision of the software infrastructure for detailed testing of the trigger system during beam down time. This is a medium-size distributed system that runs over 40 PCs and 200 processes that control about 4000 electronic boards. The architecture of this system is described using the industry-standard Universal Modeling Language (UML). This way the relationships between the different subcomponents of the system become clear and all software upgrades and modifications are simplified. The described architecture has allowed for frequent upgrades that were necessary during the commissioning phase of CMS when the trigger system evolved constantly. As a secondary objective, the paper provides a UML usage example and tries to encourage the standardization of the software documentation of large projects across the LHC and High Energy Physics community.

The architecture of the CMS Level-1 Trigger Control and Monitoring System using UML

Science.gov (United States)

Magrans de Abril, Marc; Da Rocha Melo, Jose L.; Ghabrous Larrea, Carlos; Hammer, Josef; Hartl, Christian; Lazaridis, Christos

2011-12-01

The architecture of the Compact Muon Solenoid (CMS) Level-1 Trigger Control and Monitoring software system is presented. This system has been installed and commissioned on the trigger online computers and is currently used for data taking. It has been designed to handle the trigger configuration and monitoring during data taking as well as all communications with the main run control of CMS. Furthermore its design has foreseen the provision of the software infrastructure for detailed testing of the trigger system during beam down time. This is a medium-size distributed system that runs over 40 PCs and 200 processes that control about 4000 electronic boards. The architecture of this system is described using the industry-standard Universal Modeling Language (UML). This way the relationships between the different subcomponents of the system become clear and all software upgrades and modifications are simplified. The described architecture has allowed for frequent upgrades that were necessary during the commissioning phase of CMS when the trigger system evolved constantly. As a secondary objective, the paper provides a UML usage example and tries to encourage the standardization of the software documentation of large projects across the LHC and High Energy Physics community.

The LHCb trigger in Run II

CERN Document Server

Michielin, Emanuele

2016-01-01

The LHCb trigger system has been upgraded to allow alignment, calibration and physics analysis to be performed in real time. An increased CPU capacity and improvements in the software have allowed lifetime unbiased selections of beauty and charm decays in the high level trigger. Thanks to offline quality event reconstruction already available online, physics analyses can be performed directly on this information and for the majority of charm physics selections a reduced event format can be written out. Beauty hadron decays are more efficiently triggered by re-optimised inclusive selections, and the HLT2 output event rate is increased by a factor of three.

The Run-2 ATLAS Trigger System

CERN Document Server

Ruiz-Martinez, Aranzazu; The ATLAS collaboration

2016-01-01

The ATLAS trigger has been successfully collecting collision data during the first run of the LHC between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. The trigger system consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. In Run-2, the LHC will operate at centre-of-mass energies of 13 and 14 TeV resulting in roughly five times higher trigger rates. We will briefly review the ATLAS trigger system upgrades that were implemented during the shutdown, allowing us to cope with the increased trigger rates while maintaining or even improving our efficiency to select relevant physics processes. This includes changes to the L1 calorimeter and muon trigger systems, the introduction of a new L1 topological trigger module and the merging of the previously two-level HLT system into a single event filter farm. At hand of a few examples, we will show the ...

Internal interface for RFC muon trigger electronics at CMS experiment

CERN Document Server

Pozniak, Krzysztof T; Pietrusinski, Michall

2004-01-01

The paper describes design and practical realization of an internal communication layer referred to as the Internal Interface (II). The system was realized for the RFC Muon Trigger of the CMS experiment. Fully automatic implementation of the communication layer is realized in the FPGA chips and in the control software. The methodology of implementation was presented in the description form of the interface structure from the sides of hardware and software. The examples of the communication layer realizations were given for the RFC Muon Trigger.

The updated ATLAS Jet Trigger for the LHC Run II

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00359694; The ATLAS collaboration

2015-01-01

After the current shutdown, the LHC is about to resume operation for a new data-taking period, when it will operate with increased luminosity, event rate and center of mass energy. The new conditions will impose more demanding constraints on the ATLAS online trigger reconstruction and selection system. To cope with such increased constraints, the ATLAS High-Level Trigger, placed after a first hardware-based Level~1 trigger, has been redesigned by merging two previously separated software-based processing levels. In the new joint processing level, the algorithms run in the same computing nodes, thus sharing resources, minimizing the data transfer from the detector buffers and increasing the algorithm flexibility. The jet trigger software selects events containing high transverse momentum hadronic jets. It needs optimal jet energy resolution to help rejecting an overwhelming background while retaining good efficiency for interesting jets. In particular, this requires the CPU-intensive reconstruction of tridimen...

The performance and development of the ATLAS Inner Detector Trigger

International Nuclear Information System (INIS)

Washbrook, A

2014-01-01

A description of the ATLAS Inner Detector (ID) software trigger algorithms and the performance of the ID trigger for LHC Run 1 are presented, as well as prospects for a redesign of the tracking algorithms in Run 2. The ID trigger HLT algorithms are essential for a large number of signatures within the ATLAS trigger. During the shutdown, modifications are being made to the LHC machine, to increase both the beam energy and luminosity. This in turn poses significant challenges for the trigger algorithms both in terms of execution time and physics performance. To meet these challenges the ATLAS HLT software is being restructured to run as a single stage rather than in the two distinct levels present during the Run 1 operation. This is allowing the tracking algorithms to be redesigned to make optimal use of the CPU resources available and to integrate new detector systems being added to ATLAS for post-shutdown running. Expected future improvements in the timing and efficiencies of the Inner Detector triggers are also discussed. In addition, potential improvements in the algorithm performance resulting from the additional spacepoint information from the new Insertable B-Layer are presented

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...

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...

Physics Validation of the LHC Software

CERN Multimedia

CERN. Geneva

2004-01-01

The LHC Software will be confronted to unprecedented challenges as soon as the LHC will turn on. We summarize the main Software requirements coming from the LHC detectors, triggers and physics, and we discuss several examples of Software components developed by the experiments and the LCG project (simulation, reconstruction, etc.), their validation, and their adequacy for LHC physics.

Performance of the ATLAS muon trigger in run 2

CERN Document Server

Morgenstern, Marcus; The ATLAS collaboration

2017-01-01

Triggering on muons is a crucial ingredient to fulfill the physics program of the ATLAS experiments. The ATLAS trigger system deploys a two stage strategy, a hardware-based Level-1 trigger and a software-based high-level trigger to select events of interest at a suitable recording rate. Both stages underwent upgrades to cope with the challenges in run-II data-taking at centre-of-mass energies of 13 TeV and instantaneous luminosities up to 2x10$^{34} cm^{-2}s^{-1}$. The design of the ATLAS muon triggers and their performance in proton-proton collisions at 13 TeV are presented.

Rate Predictions and Trigger/DAQ Resource Monitoring in ATLAS

CERN Document Server

Schaefer, D M; The ATLAS collaboration

2012-01-01

Since starting in 2010, the Large Hadron Collider (LHC) has pro- duced collisions at an ever increasing rate. The ATLAS experiment successfully records the collision data with high eciency and excel- lent data quality. Events are selected using a three-level trigger system, where each level makes a more re ned selection. The level-1 trigger (L1) consists of a custom-designed hardware trigger which seeds two higher software based trigger levels. Over 300 triggers compose a trig- ger menu which selects physics signatures such as electrons, muons, particle jets, etc. Each trigger consumes computing resources of the ATLAS trigger system and oine storage. The LHC instantaneous luminosity conditions, desired physics goals of the collaboration, and the limits of the trigger infrastructure determine the composition of the ATLAS trigger menu. We describe a trigger monitoring frame- work for computing the costs of individual trigger algorithms such as data request rates and CPU consumption. This framework has been used...

The ATLAS Trigger: Recent Experience and Future Plans

CERN Document Server

The ATLAS collaboration

2009-01-01

This paper will give an overview of the ATLAS trigger design and its innovative features. It will describe the valuable experience gained in running the trigger reconstruction and event selection in the fastchanging environment of the detector commissioning during 2008. It will also include a description of the trigger selection menu and its 2009 deployment plan from first collisions to the nominal luminosity. ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). The trigger system needs to efficiently reject a large rate of background events and still select potentially interesting ones with high efficiency. After a first level trigger implemented in custom electronics, the trigger event selection is made by the High Level Trigger (HLT) system, implemented in software. To reduce the processing time to manageable levels, the HLT uses seeded, step-wise and fast selection algorithms, aiming at the earliest possible rejection of background events. The ATLAS trigger event selection...

Simulations and Prototyping of the LHCb L1 and HLT Triggers

CERN Document Server

Shears, T; Kechadi, T; McNulty, R; Smoker, A; Barczyk, A; Dufey, J; Jost, B; Neufeld, N

2004-01-01

The Level 1 (L1) and High Level Triggers (HLT) for the LHCb experiment are software triggers which will be implemented on a farm of approximately 1800 computers, connected via a Gigabit LAN with a bandwidth capacity of 7.1 GB/s and containing some 500 Ethernet links. The architecture of the readout network must be optimised to maximise data throughput, control data flow and minimise errors. We report on the development and results of two independent software simulations which allow us to evaluate the performance of various network configurations. We also describe the construction of two hardware testbeds of the LHCb L1 and HLT trigger system, which allow microscopic and macroscopic study of network and switch behaviour.

ATLAS FTK Fast Track Trigger

CERN Document Server

Iizawa, T; The ATLAS collaboration

2014-01-01

The Fast TracKer (FTK) will perform global track reconstruction after each Level-1 trigger accept signal to enable the software-based higher level trigger to have early access to tracking information. FTK is a dedicated processor based on a mixture of advanced technologies. Modern, powerful Field Programmable Gate Arrays (FPGAs) form an important part of the system architecture, and the large level of computing power required for pattern recognition is provided by incorporating standard-cell ASICs named Associative Memory (AM). Motivation and the architecture of the FTK system will be presented, and the status of hardware and simulation will be following.

A new scheme for ATLAS trigger simulation using legacy code

International Nuclear Information System (INIS)

Galster, Gorm; Stelzer, Joerg; Wiedenmann, Werner

2014-01-01

Analyses at the LHC which search for rare physics processes or determine with high precision Standard Model parameters require accurate simulations of the detector response and the event selection processes. The accurate determination of the trigger response is crucial for the determination of overall selection efficiencies and signal sensitivities. For the generation and the reconstruction of simulated event data, the most recent software releases are usually used to ensure the best agreement between simulated data and real data. For the simulation of the trigger selection process, however, ideally the same software release that was deployed when the real data were taken should be used. This potentially requires running software dating many years back. Having a strategy for running old software in a modern environment thus becomes essential when data simulated for past years start to present a sizable fraction of the total. We examined the requirements and possibilities for such a simulation scheme within the ATLAS software framework and successfully implemented a proof-of-concept simulation chain. One of the greatest challenges was the choice of a data format which promises long term compatibility with old and new software releases. Over the time periods envisaged, data format incompatibilities are also likely to emerge in databases and other external support services. Software availability may become an issue, when e.g. the support for the underlying operating system might stop. In this paper we present the encountered problems and developed solutions, and discuss proposals for future development. Some ideas reach beyond the retrospective trigger simulation scheme in ATLAS as they also touch more generally aspects of data preservation.

The ATLAS Trigger System: Ready for Run-2

CERN Document Server

Maeda, Junpei; The ATLAS collaboration

2015-01-01

The ATLAS trigger has been successfully collecting collision data during the first run of the LHC between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. The trigger system consists of a hardware Level-1 and a software based high-level trigger that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. During the data-taking period of Run-2 the LHC will operate at a centre-of-mass energy of about 13 TeV resulting in roughly five times higher trigger rates. In these proceedings, we briefly review the ATLAS trigger system upgrades that were implemented during the shutdown, allowing us to cope with the increased trigger rates while maintaining or even improving our efficiency to select relevant physics processes. This includes changes to the Level-1 calorimeter and muon trigger system, the introduction of a new Level-1 topological trigger module and themerging of the previously two-level higher-level trigger system into a single even...

Upgrade Software and Computing

CERN Document Server

The LHCb Collaboration, CERN

2018-01-01

This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis.

NOvA Event Building, Buffering and Data-Driven Triggering From Within the DAQ System

Energy Technology Data Exchange (ETDEWEB)

Fischler, M. [Fermilab; Green, C. [Fermilab; Kowalkowski, J. [Fermilab; Norman, A. [Fermilab; Paterno, M. [Fermilab; Rechenmacher, R. [Fermilab

2012-06-22

To make its core measurements, the NOvA experiment needs to make real-time data-driven decisions involving beam-spill time correlation and other triggering issues. NOvA-DDT is a prototype Data-Driven Triggering system, built using the Fermilab artdaq generic DAQ/Event-building tools set. This provides the advantages of sharing online software infrastructure with other Intensity Frontier experiments, and of being able to use any offline analysis module--unchanged--as a component of the online triggering decisions. The NOvA-artdaq architecture chosen has significant advantages, including graceful degradation if the triggering decision software fails or cannot be done quickly enough for some fraction of the time-slice ``events.'' We have tested and measured the performance and overhead of NOvA-DDT using an actual Hough transform based trigger decision module taken from the NOvA offline software. The results of these tests--98 ms mean time per event on only 1/16 of th e available processing power of a node, and overheads of about 2 ms per event--provide a proof of concept: NOvA-DDT is a viable strategy for data acquisition, event building, and trigger processing at the NOvA far detector.

The ATLAS Trigger System : Ready for Run-2

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00211007; The ATLAS collaboration

2016-01-01

The ATLAS trigger has been successfully collecting collision data during the first run of the LHC between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. The trigger system consists of a hardware based Level-1 (L1) and a software based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. During the course of the ongoing Run-2 data-taking campaign at 13 TeV centre-of-mass energy the trigger rates will be approximately 5 times higher compared to Run-1. In these proceedings we briefly review the ATLAS trigger system upgrades that were implemented during the shutdown, allowing us to cope with the increased trigger rates while maintaining or even improving our efficiency to select relevant physics processes. This includes changes to the L1 calorimeter and muon trigger system, the introduction of a new L1 topological trigger subsystem and the merging of the previously two-level HLT system into a single ev...

DZERO Level 3 DAQ/Trigger Closeout

CERN Multimedia

CERN. Geneva

2012-01-01

The Tevatron Collider, located at the Fermi National Accelerator Laboratory, delivered its last 1.96 TeV proton-antiproton collisions on September 30th, 2011. The DZERO experiment continues to take cosmic data for final alignment for several more months . Since Run 2 started, in March 2001, all DZERO data has been collected by the DZERO Level 3 Trigger/DAQ System. The system is a modern, networked, commodity hardware trigger and data acquisition system based around a large central switch with about 60 front ends and 200 trigger computers. DZERO front end crates are VME based. Single Board Computer interfaces between detector data on VME and the network transport for the DAQ system. Event flow is controlled by the Routing Master which can steer events to clusters of farm nodes based on the low level trigger bits that fired. The farm nodes are multi-core commodity computer boxes, without special hardware, that run isolated software to make the final Level 3 trigger decision. Passed events are transferred to th...

The CMS trigger in Run 2

CERN Document Server

Tosi, Mia

2018-01-01

During its second period of operation (Run 2) which started in 2015, the LHC will reach a peak instantaneous luminosity of approximately 2$\\times 10^{34}$~cm$^{-2}s^{-1}$ with an average pile-up of about 55, far larger than the design value. Under these conditions, the online event selection is a very challenging task. In CMS, it is realised by a two-level trigger system: the Level-1 (L1) Trigger, implemented in custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the offline reconstruction software running on a computer farm.\\\\ In order to face this challenge, the L1 trigger has undergone a major upgrade compared to Run 1, whereby all electronic boards of the system have been replaced, allowing more sophisticated algorithms to be run online. Its last stage, the global trigger, is now able to perform complex selections and to compute high-level quantities, like invariant masses. Likewise, the algorithms that run in the HLT went through big improvements; in particular, new ap...

Recent experience and future evolution of the CMS High Level Trigger System

CERN Document Server

Bauer, Gerry; Branson, James; Bukowiec, Sebastian Czeslaw; Chaze, Olivier; Cittolin, Sergio; Coarasa Perez, Jose Antonio; Deldicque, Christian; Dobson, Marc; Dupont, Aymeric; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gomez-Reino Garrido, Robert; Hartl, Christian; Holzner, Andre Georg; Masetti, Lorenzo; Meijers, Franciscus; Meschi, Emilio; Mommsen, Remigius; Nunez Barranco Fernandez, Carlos; O'Dell, Vivian; Orsini, Luciano; Paus, Christoph Maria Ernst; Petrucci, Andrea; Pieri, Marco; Polese, Giovanni; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schwick, Christoph; Spataru, Andrei Cristian; Stoeckli, Fabian; Sumorok, Konstanty

2012-01-01

The CMS experiment at the LHC uses a two-stage trigger system, with events flowing from the first level trigger at a rate of 100 kHz. These events are read out by the Data Acquisition system (DAQ), assembled in memory in a farm of computers, and finally fed into the high-level trigger (HLT) software running on the farm. The HLT software selects interesting events for offline storage and analysis at a rate of a few hundred Hz. The HLT algorithms consist of sequences of offline-style reconstruction and filtering modules, executed on a farm of 0(10000) CPU cores built from commodity hardware. Experience from the 2010-2011 collider run is detailed, as well as the current architecture of the CMS HLT, and its integration with the CMS reconstruction framework and CMS DAQ. The short- and medium-term evolution of the HLT software infrastructure is discussed, with future improvements aimed at supporting extensions of the HLT computing power, and addressing remaining performance and maintenance issues.

The LHCb trigger and data acquisition system

CERN Document Server

Dufey, J P; Harris, F; Harvey, J; Jost, B; Mato, P; Müller, E

2000-01-01

The LHCb experiment is the most recently approved of the 4 experiments under construction at CERNs LHC accelerator. It is a special purpose experiment designed to precisely measure the CP violation parameters in the B-B system. Triggering poses special problems since the interesting events containing B-mesons are immersed in a large background of inelastic p-p reactions. We therefore decided to implement a 4 level triggering scheme. The LHCb Data Acquisition (DAQ) system will have to cope with an average trigger rate of ~40 kHz, after two levels of hardware triggers, and an average event size of ~100 kB. Thus an event-building network which can sustain an average bandwidth of 4 GB/s is required. A powerful software trigger farm will have to be installed to reduce the rate from the 40 kHz to ~100 Hz of events written to permanent storage. In this paper we outline the general architecture of the Trigger and DAQ system and the readout protocols we plan to implement. First results of simulations of the behavior o...

The Run-2 ATLAS Trigger System

International Nuclear Information System (INIS)

Martínez, A Ruiz

2016-01-01

The ATLAS trigger successfully collected collision data during the first run of the LHC between 2009-2013 at different centre-of-mass energies between 900 GeV and 8TeV. The trigger system consists of a hardware Level-1 and a software-based high level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. In Run-2, the LHC will operate at centre-of-mass energies of 13 and 14 TeV and higher luminosity, resulting in up to five times higher rates of processes of interest. A brief review of the ATLAS trigger system upgrades that were implemented between Run-1 and Run-2, allowing to cope with the increased trigger rates while maintaining or even improving the efficiency to select physics processes of interest, will be given. This includes changes to the Level-1 calorimeter and muon trigger systems, the introduction of a new Level-1 topological trigger module and the merging of the previously two-level HLT system into a single event processing farm. A few examples will be shown, such as the impressive performance improvements in the HLT trigger algorithms used to identify leptons, hadrons and global event quantities like missing transverse energy. Finally, the status of the commissioning of the trigger system and its performance during the 2015 run will be presented. (paper)

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.

Use of GPUs in Trigger Systems

Science.gov (United States)

Lamanna, Gianluca

In recent years the interest for using graphics processor (GPU) in general purpose high performance computing is constantly rising. In this paper we discuss the possible use of GPUs to construct a fast and effective real time trigger system, both in software and hardware levels. In particular, we study the integration of such a system in the NA62 trigger. The first application of GPUs for rings pattern recognition in the RICH will be presented. The results obtained show that there are not showstoppers in trigger systems with relatively low latency. Thanks to the use of off-the-shelf technology, in continous development for purposes related to video game and image processing market, the architecture described would be easily exported to other experiments, to build a versatile and fully customizable online selection.

Green Software Products

NARCIS (Netherlands)

Jagroep, E.A.

2017-01-01

The rising energy consumption of the ICT industry has triggered a quest for more green, energy efficient ICT solutions. The role of software as the true consumer of power and its potential contribution to reach sustainability goals has increasingly been acknowledged. At the same time, it is shown to

The LHCb trigger and its performance in 2011

International Nuclear Information System (INIS)

Aaij, R; Beuzekom, M van; Coco, V; Albrecht, J; Alessio, F; Bonaccorsi, E; Brarda, L; Cattaneo, M; Chebbi, M; Clemencic, M; Closier, J; Amato, S; Aslanides, E; Cogan, J; Belyaev, I; Bonnefoy, R; Chanal, H; Deschamps, O; Callot, O; Vidal, X Cid

2013-01-01

This paper presents the design of the LHCb trigger and its performance on data taken at the LHC in 2011. A principal goal of LHCb is to perform flavour physics measurements, and the trigger is designed to distinguish charm and beauty decays from the light quark background. Using a combination of lepton identification and measurements of the particles' transverse momenta the trigger selects particles originating from charm and beauty hadrons, which typically fly a finite distance before decaying. The trigger reduces the roughly 11 MHz of bunch-bunch crossings that contain at least one inelastic pp interaction to 3 kHz. This reduction takes place in two stages; the first stage is implemented in hardware and the second stage is a software application that runs on a large computer farm. A data-driven method is used to evaluate the performance of the trigger on several charm and beauty decay modes.

The ATLAS Trigger System: Ready for Run II

CERN Document Server

Czodrowski, Patrick; The ATLAS collaboration

2015-01-01

The ATLAS trigger system has been used successfully for data collection in the 2009-2013 Run 1 operation cycle of the CERN Large Hadron Collider (LHC) at center-of-mass energies of up to 8 TeV. With the restart of the LHC for the new Run 2 data-taking period at 13 TeV, the trigger rates are expected to rise by approximately a factor of 5. The trigger system consists of a hardware-based first level (L1) and a software-based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of ~ 1kHz. This presentation will give an overview of the upgrades to the ATLAS trigger system that have been implemented during the LHC shutdown period in order to deal with the increased trigger rates while efficiently selecting the physics processes of interest. These upgrades include changes to the L1 calorimeter trigger, the introduction of a new L1 topological trigger module, improvements in the L1 muon system, and the merging of the previously two-level HLT ...

The ATLAS Trigger System: Ready for Run-2

CERN Document Server

Nakahama, Yu; The ATLAS collaboration

2015-01-01

The ATLAS trigger has been used very successfully for the online event selection during the first run of the LHC between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. The trigger system consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. During the next data-taking period starting in early 2015 (Run-2) the LHC will operate at a centre-of-mass energy of about 13 TeV resulting in roughly five times higher trigger rates. We will review the upgrades to the ATLAS Trigger system that have been implemented during the shutdown and that will allow us to cope with these increased trigger rates while maintaining or even improving our efficiency to select relevant physics processes. This includes changes to the L1 calorimeter trigger, the introduction of a new L1 topological trigger module, improvements in the L1 muon system and the merging of the prev...

The ATLAS Trigger System: Ready for Run-2

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00211007; The ATLAS collaboration

2015-01-01

The ATLAS trigger has been successfully collecting collision data during the first run of the LHC between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. The trigger system consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. During the next data-taking period starting in 2015 (Run-2) the LHC will operate at a centre-of-mass energy of about 13 TeV resulting in roughly five times higher trigger rates. We will briefly review the ATLAS trigger system upgrades that were implemented during the shutdown, allowing us to cope with the increased trigger rates while maintaining or even improving our efficiency to select relevant physics processes. This includes changes to the L1 calorimeter and muon trigger system, the introduction of a new L1 topological trigger module and the merging of the previously two-level HLT system into a single event filter fa...

Quantifying Update Effects in Citizen-Oriented Software

Directory of Open Access Journals (Sweden)

Ion Ivan

2009-02-01

Full Text Available Defining citizen-oriented software. Detailing technical issues regarding update process in this kind of software. Presenting different effects triggered by types of update. Building model for update costs estimation, including producer-side and consumer-side effects. Analyzing model applicability on INVMAT – large scale matrix inversion software. Proposing a model for update effects estimation. Specifying ways for softening effects of inaccurate updates.

Performance of the ATLAS Muon Trigger in Run 2

CERN Document Server

Morgenstern, Marcus; The ATLAS collaboration

2018-01-01

Events containing muons in the final state are an important signature for many analyses being carried out at the Large Hadron Collider (LHC), including both standard model measurements and searches for new physics. To be able to study such events, it is required to have an efficient and well-understood muon trigger. The ATLAS muon trigger consists of a hardware based system (Level 1), as well as a software based reconstruction (High Level Trigger). Due to high luminosity and pile up conditions in Run 2, several improvements have been implemented to keep the trigger rate low while still maintaining a high efficiency. Some examples of recent improvements include requiring coincidence hits between different layers of the muon spectrometer, improvements for handling overlapping muons, and optimised muon isolation. We will present an overview of how we trigger on muons, recent improvements, and the performance of the muon trigger in Run 2 data.

The ATLAS Trigger in Run-2 - Design, Menu and Performance

CERN Document Server

Vazquez Schroeder, Tamara; The ATLAS collaboration

2017-01-01

The ATLAS trigger has been used very successfully for online event selection during the first part of the second LHC run (Run-2) in 2015/16 at a center-of-mass energy of 13 TeV. The trigger system is composed of a hardware Level-1 trigger and a software-based high-level trigger. Events are selected based on physics signatures such as presence of energetic leptons, photons, jets or large missing energy. The trigger system exploits topological information, as well as multi-variate methods to carry out the necessary physics filtering. In total, the ATLAS online selection consists of thousands of different individual triggers. Taken together constitute the trigger menu, which reflects the physics goals of the collaboration while taking into account available data taking resources. The trigger selection capabilities of ATLAS during Run-2 have been significantly improved compared to Run-1, in order to cope with the higher event rates and number of interactions per bunch crossing (pileup) which are the result of the...

Tools for Trigger Rate Monitoring at CMS

CERN Document Server

Smith, Geoffrey; Wightman, Andrew Steven

2017-01-01

In 2017, we expect the LHC to deliver an instantaneous luminosity of roughly $2.0 \\times 10^{34}$~cm$^{-2}$s$^{-1}$ to the Compact Muon Solenoid (CMS) experiment, with about 60 simultaneous proton-proton collisions (pileup) per event. In these challenging conditions, it is important to be able to intelligently monitor the rate at which data are being collected (the trigger rate). It is not enough to simply look at the trigger rate; it is equally important to compare the trigger rate with expectations. We present a set of software tools that have been developed to accomplish this. The tools include a real-time component - a script that monitors the rates of individual triggers during data-taking, and activates an alarm if rates deviate significantly from expectation. Fits are made to previously collected data and extrapolated to higher pileup. The behavior of triggers as a function of pileup is then monitored as data are collected - plots are automatically produced on an hourly basis and uploaded to a web area...

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...

LHCb : The LHCb trigger system and its upgrade

CERN Multimedia

Dziurda, Agnieszka

2015-01-01

The current LHCb trigger system consists of a hardware level, which reduces the LHC inelastic collision rate of 30 MHz to 1 MHz, at which the entire detector is read out. In a second level, implemented in a farm of 20k parallel-processing CPUs, the event rate is reduced to about 5 kHz. We review the performance of the LHCb trigger system during Run I of the LHC. Special attention is given to the use of multivariate analyses in the High Level Trigger. The major bottleneck for hadronic decays is the hardware trigger. LHCb plans a major upgrade of the detector and DAQ system in the LHC shutdown of 2018, enabling a purely software based trigger to process the full 30 MHz of inelastic collisions delivered by the LHC. We demonstrate that the planned architecture will be able to meet this challenge. We discuss the use of disk space in the trigger farm to buffer events while performing run-by-run detector calibrations, and the way this real time calibration and subsequent full event reconstruction will allow LHCb to ...

L2TTMON Monitoring Program for L2 Topological Trigger in H1 Experiment - User's Guide

International Nuclear Information System (INIS)

Banas, E.; Ducorps, A.

1999-01-01

Monitoring software for the L2 Topological Trigger in H1 experiment consists of two parts working on two different computers. The hardware read-out and data processing is done on a fast FIC 8234 computer working with the OS9 real time operating system. The Macintosh Quadra is used as a Graphic User Interface for accessing the OS9 trigger monitoring software. The communication between both computers is based on the parallel connection between the Macintosh and the VME crate, where the FIC computer is placed. The special designed protocol (client-server) is used to communicate between both nodes. The general scheme of monitoring for the L2 Topological Trigger and detailed description of using of the monitoring software in both nodes are given in this guide. (author)

The Hardware Topological Trigger of ATLAS: Commissioning and Operations

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00226165; The ATLAS collaboration

2018-01-01

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. To improve the physics potential reach in ATLAS, during the LHC shutdown after Run 1, the Level-1 trigger system was upgraded at hardware, firmware and software level. In particular, a new electronics sub-system was 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. For individual blades, real-time information from calorimeter and muon Level-1 trigger systems, is processed by four individual state-of-the-art FPGAs. It needs to deal with a large input bandwidth of up to 6 Tb/s, optical connectivity and low processing latency on the real-time data path. The L1Topo firmware apply measurements of angles between jets and/or leptons and several...

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 ...

The ATLAS Trigger Algorithms for General Purpose Graphics Processor Units

CERN Document Server

Tavares Delgado, Ademar; The ATLAS collaboration

2016-01-01

The ATLAS Trigger Algorithms for General Purpose Graphics Processor Units Type: Talk Abstract: We present the ATLAS Trigger algorithms developed to exploit General­ Purpose Graphics Processor Units. ATLAS is a particle physics experiment located on the LHC collider at CERN. The ATLAS Trigger system has two levels, hardware-­based Level 1 and the High Level Trigger implemented in software running on a farm of commodity CPU. Performing the trigger event selection within the available farm resources presents a significant challenge that will increase future LHC upgrades. are being evaluated as a potential solution for trigger algorithms acceleration. Key factors determining the potential benefit of this new technology are the relative execution speedup, the number of GPUs required and the relative financial cost of the selected GPU. We have developed a trigger demonstrator which includes algorithms for reconstructing tracks in the Inner Detector and Muon Spectrometer and clusters of energy deposited in the Cal...

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...

Development of Methods and Means of Configuration Data Transfer For Use in an FPGA Based Trigger Controller Device

International Nuclear Information System (INIS)

2010-01-01

To determine if klystrons will perform to the specifications of the LCLS (Linac Coherent Light Source) project, a new digital trigger controller is needed for the Klystron/Microwave Department Test Laboratory. The controller needed to be programmed and Windows based user interface software needed to be written to interface with the device over a USB (Universal Serial Bus). Programming the device consisted of writing logic in VHDL (VHSIC (Very High Speed Integrated Circuits) hardware description language), and the Windows interface software was written in C++. Xilinx ISE (Integrated Software Environment) was used to compile the VHDL code and program the device, and Microsoft Visual Studio 2005 was used to compile the C++ based Windows software. The device was programmed in such a way as to easily allow read/write operations to it using a simple addressing model, and Windows software was developed to interface with the device over a USB connection. A method of setting configuration registers in the trigger device is absolutely necessary to the development of a new triggering system, and the method developed will fulfill this need adequately. More work is needed before the new trigger system is ready for use. The configuration registers in the device need to be fully integrated with the logic that will generate the RF signals, and this system will need to be tested extensively to determine if it meets the requirements for low noise trigger outputs.

Synchronized analysis of testbeam data with the Judith software

CERN Document Server

McGoldrick, Garrin; Gorišek, Andrej

2014-01-01

The Judith software performs pixel detector analysis tasks utilizing two different data streams such as those produced by the reference and tested devices typically found in a testbeam. This software addresses and fixes problems arising from the desynchronization of the two simultaneously triggered data streams by detecting missed triggers in either of the streams. The software can perform all tasks required to generate particle tracks using multiple detector planes: it can align the planes, cluster hits and generate tracks from these clusters. This information can then be used to measure the properties of a particle detector with very fine spatial resolution. It was tested at DESY in the Kartel telescope, a silicon tracking detector, with ATLAS Diamond Beam Monitor modules as a device under test.

Proceedings of the workshop on triggering and data acquisition for experiments at the Supercollider

Energy Technology Data Exchange (ETDEWEB)

Donaldson, R. [ed.

1989-04-01

This meeting covered the following subjects: triggering requirements for SSC physics; CDF level 3 trigger; D0 trigger design; AMY trigger systems; Zeus calorimeter first level trigger; data acquisition for the Zeus Central Tracking Detector; trigger and data acquisition aspects for SSC tracking; data acquisition systems for the SSC; validating triggers in CDF level 3; optical data transmission at SSC; time measurement system at SSC; SSC/BCD data acquisition system; microprocessors and other processors for triggering and filtering at the SSC; data acquisition, event building, and on-line processing; LAA real-time benchmarks; object-oriented system building at SSC; and software and project management. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

The ATLAS Trigger algorithms upgrade and performance in Run 2

CERN Document Server

Bernius, Catrin; The ATLAS collaboration

2017-01-01

Title: The ATLAS Trigger algorithms upgrade and performance in Run 2 (TDAQ) The ATLAS trigger has been used very successfully for the online event selection during the first part of the second LHC run (Run-2) in 2015/16 at a center-of-mass energy of 13 TeV. The trigger system is composed of a hardware Level-1 trigger and a software-based high-level trigger; it reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of about 1 kHz. The excellent performance of the ATLAS trigger has been vital for the ATLAS physics program of Run-2, selecting interesting collision events for wide variety of physics signatures with high efficiency. The trigger selection capabilities of ATLAS during Run-2 have been significantly improved compared to Run-1, in order to cope with the higher event rates and pile-up which are the result of the almost doubling of the center-of-mass collision energy and the increase in the instantaneous luminosity of the LHC. At the Level-1 trigger the undertaken impr...

Level-1 track trigger for the upgrade of the CMS detector at HL-LHC

CERN Document Server

Ahuja, Sudha

2016-01-01

The Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) studies proton-proton collisions at a centre-of-mass energy of 13 TeV. With the LHC colliding proton bunches every 25 nanoseconds, the volume and rate of raw data produced by the detector are much larger than what can be read out, recorded, and reconstructed. Therefore, an efficient trigger system is required to identify events of interest in real time and to reduce the rate of events to a manageable level for later software reconstruction. The CMS trigger system consists of two processing stages, a level-1 (L1) hardware trigger and a high level software trigger. The current L1 trigger decision relies solely on calorimetric and muon system information. During the High Luminosity LHC (HL-LHC) era, the instantaneous luminosity of the collider is expected to increase by approximately an order of magnitude, resulting in a significantly larger number of collisions per bunch crossing than observed in the current run. In order to preserve ...

Search for prompt neutrinos with AMANDA-II

International Nuclear Information System (INIS)

Gozzini, Sara Rebecca

2008-01-01

The investigation performed in this work aims to identify and disentangle the signal of prompt neutrinos from the inclusive atmospheric spectrum. We have analysed data recorded in the years 2000-2003 by the AMANDA-II detector at the geographical South Pole. After a tight event selection, our sample is composed of about 4 . 10 3 atmospheric neutrinos. Prompt neutrinos are decay products of heavy quark hadrons, which are produced in the collision of a cosmic ray particle with a nucleon in the atmosphere. The technique used to recognise prompt neutrinos is based on a simulated information of their energy spectrum, which appears harder than that of the conventional component from light quarks. Models accounting for different hadron production and decay schemes have been included in a Monte Carlo simulation and convoluted with the detector response, in order to reproduce the different spectra. The background of conventional events has been described with the Bartol 2006 tables. The energy spectrum of our data has been reconstructed through a numerical unfolding algorithm. The reconstruction is based on a Monte Carlo simulation and uses as an input three parameters of the neutrino track which are correlated with the energy of the event. Numerical regularisation is introduced to achieve a result free of unphysical oscillations, typical unfortunate feature of unfolding. The reconstructed data spectrum has been compared with different predictions using the model rejection factor technique. The prompt neutrino models differ in the choice of the hadron interaction model, the set of parton distribution functions and the numerical parameterisation of the fragmentation functions describing the transition from quark to hadrons. Here we considered mainly three classes of models, known in the literature as the Recombination Quark Parton Model, the Quark Gluon String Model and the Perturbative QCD model. Upper limits have been set on the expected flux predictions, based on our

The CMS High Level Trigger System: Experience and Future Development

CERN Document Server

Bauer, Gerry; Bowen, Matthew; Branson, James G; Bukowiec, Sebastian; Cittolin, Sergio; Coarasa, J A; Deldicque, Christian; Dobson, Marc; Dupont, Aymeric; Erhan, Samim; Flossdorf, Alexander; Gigi, Dominique; Glege, Frank; Gomez-Reino, R; Hartl, Christian; Hegeman, Jeroen; Holzner, André; Y L Hwong; Masetti, Lorenzo; Meijers, Frans; Meschi, Emilio; Mommsen, R K; O'Dell, Vivian; Orsini, Luciano; Paus, Christoph; Petrucci, Andrea; Pieri, Marco; Polese, Giovanni; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schwick, Christoph; Shpakov, Dennis; Simon, M; Spataru, A C; Sumorok, Konstanty

2012-01-01

The CMS experiment at the LHC features a two-level trigger system. Events accepted by the first level trigger, at a maximum rate of 100 kHz, are read out by the Data Acquisition system (DAQ), and subsequently assembled in memory in a farm of computers running a software high-level trigger (HLT), which selects interesting events for offline storage and analysis at a rate of order few hundred Hz. The HLT algorithms consist of sequences of offline-style reconstruction and filtering modules, executed on a farm of 0(10000) CPU cores built from commodity hardware. Experience from the operation of the HLT system in the collider run 2010/2011 is reported. The current architecture of the CMS HLT, its integration with the CMS reconstruction framework and the CMS DAQ, are discussed in the light of future development. The possible short- and medium-term evolution of the HLT software infrastructure to support extensions of the HLT computing power, and to address remaining performance and maintenance issues, are discussed.

Development of trigger software for the silicon and fibre trackers and a study of B meson lifetimes for the D0 experiment

International Nuclear Information System (INIS)

Illingworth, Robert Arthur; Imperial Coll., London

2002-01-01

The D0 detector has recently undergone a major upgrade to maximize its potential to fully exploit Run II at the Tevatron 2 TeV proton-antiproton collider. The upgrade includes a completely new central tracking system with an outer scintillating fibre tracker and an inner silicon vertex detector. This thesis describes the development of the software to ''unpack'' the raw data from the central tracking detectors into a useful form, and the development of the Level 3 trigger algorithms to cluster the hit information from these detectors. One of the many areas of physics that is being studied by the D0 experiment is the physics of B mesons, particularly that involving CP violation. The second part of the thesis details a constrained mass fitting tool written to aid the reconstruction of B particles, and a Monte Carlo study into measuring the lifetime of B + and B 0 mesons. This thesis lays the foundations for the means by which physics is extracted from the vast amount of Tevatron data--the trigger--and illustrates how analyses will proceed through the key reconstruction of heavy quarks

Performance of the CMS High Level Trigger

CERN Document Server

Perrotta, Andrea

2015-01-01

The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increases in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. The increase in the number of interactions per bunch crossing, on average 25 in 2012, and expected to be around 40 in Run II, will be an additional complication. We present here the expected performance of the main triggers that will be used during the 2015 data taking campaign, paying particular attention to the new approaches that have been developed to cope with the challenges of the new run. This includes improvements in HLT electron and photon reconstruction as well as better performing muon triggers. We will also present the performance of the improved trac...

The ATLAS Trigger system upgrade and performance in Run 2

CERN Document Server

Shaw, Savanna Marie; The ATLAS collaboration

2017-01-01

The ATLAS trigger has been used very successfully for the online event selection during the first part of the LHC Run-2 in 2015/16 at a centre-of-mass energy of 13 TeV. The trigger system is composed of a hardware Level-1 trigger and a software-based high-level trigger; it reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of about 1 kHz. The excellent performance of the ATLAS trigger has been vital for the ATLAS physics program of Run-2, selecting interesting collision events for wide variety of physics signatures with high efficiency. The trigger selection capabilities of ATLAS during Run-2 have been significantly improved compared to Run-1, in order to cope with the higher event rates and pile-up which are the result of the almost doubling of the center-of-mass collision energy and the increase in the instantaneous luminosity of the LHC. In order to prepare for the anticipated further luminosity increase of the LHC in 2017/18, improving the trigger performance remain...

The ATLAS Trigger Algorithms Upgrade and Performance in Run-2

CERN Document Server

Bernius, Catrin; The ATLAS collaboration

2017-01-01

The ATLAS trigger has been used very successfully for the online event selection during the first part of the second LHC run (Run-2) in 2015/16 at a center-of-mass energy of 13 TeV. The trigger system is composed of a hardware Level-1 trigger and a software-based high-level trigger; it reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of about 1 kHz. The excellent performance of the ATLAS trigger has been vital for the ATLAS physics program of Run-2, selecting interesting collision events for wide variety of physics signatures with high efficiency. The trigger selection capabilities of ATLAS during Run-2 have been significantly improved compared to Run-1, in order to cope with the higher event rates and pile-up which are the result of the almost doubling of the center-of-mass collision energy and the increase in the instantaneous luminosity of the LHC. At the Level-1 trigger the undertaken improvements resulted in more pile-up robust selection efficiencies and event ra...

The ATLAS Trigger system upgrade and performance in Run 2

CERN Document Server

Shaw, Savanna Marie; The ATLAS collaboration

2018-01-01

The ATLAS trigger has been used very successfully for the online event selection during the first part of the second LHC run (Run-2) in 2015/16 at a centre-of-mass energy of 13 TeV. The trigger system is composed of a hardware Level-1 trigger and a software-based high-level trigger; it reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of about 1 kHz. The excellent performance of the ATLAS trigger has been vital for the ATLAS physics program of Run-2, selecting interesting collision events for wide variety of physics signatures with high efficiency. The trigger selection capabilities of ATLAS during Run-2 have been significantly improved compared to Run-1, in order to cope with the higher event rates and pile-up which are the result of the almost doubling of the center-of-mass collision energy and the increase in the instantaneous luminosity of the LHC. At the Level-1 trigger the undertaken improvements resulted in more pile-up robust selection efficiencies and event ra...

Report from the June Trigger and Physics Week

CERN Multimedia

Chris Bee

The week of June 4th saw the 5th ATLAS Trigger and Physics week at CERN. The meeting, bringing together people working in the trigger, data preparation, detector combined-performance and physics groups, aimed at focusing work and discussions on preparing ATLAS for first data-taking. The meeting started on Monday afternoon with a set of plenary presentations on topics ranging from software status and validation, the ATLAS analysis model and its implications for the computing model, and initial ideas for trigger menus for the expected LHC start-up luminosity of 1031cm-2s-1. There was also a report from Peter Jenni on the expected LHC start-up schedule. The participation exceeded the organisers' wildest dreams as the CERN Council Chamber (seating capacity 160) proved woefully inadequate to seat everyone. A packed Council Chamber for the opening plenary Tuesday was dedicated to parallel sessions of the trigger and combined performance groups. A great deal of progress was presented in all areas, notably 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 ...

The Architecture of the CMS Level-1 Trigger Control and Monitoring System

CERN Document Server

Magrans de Abril, Marc; Hammer, Josef; Hartl, Christian; Xie, Zhen

2011-01-01

The architecture of the Level-1 Trigger Control and Monitoring system for the CMS experiment is presented. This system has been installed and commissioned on the trigger online computers and is currently used for data taking at the LHC. This is a medium-size distributed system that runs over 40 PCs and 200 processes that control about 4000 electronic boards. It has been designed to handle the trigger configuration and monitoring during data taking as well as all communications with the main run control of CMS. Furthermore its design has foreseen the provision of the software infrastructure for detailed testing of the trigger system during beam down time.

The readiness of ATLAS Trigger-DAQ system for the second LHC run

CERN Document Server

Rammensee, Michael; The ATLAS collaboration

2015-01-01

After its first shutdown, LHC will provide pp collisions with increased luminosity and energy. In the ATLAS experiment, the Trigger and Data Acquisition (TDAQ) system has been upgraded to deal with the increased event rates. The updated system is radically different from the previous implementation, both in terms of architecture and expected performance. The main architecture has been reshaped in order to profit from the technological progress and to maximize the flexibility and efficiency of the data selection process. The trigger system in ATLAS consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT) that reduces the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of a few hundred Hz. The pre-existing two-level software filtering, known as L2 and the Event Filter, are now merged into a single process, performing incremental data collection and analysis. This design has many advantages, among which are: the radical simplification of the architec...

LHCb detector and trigger performance in Run II

Science.gov (United States)

Francesca, Dordei

2017-12-01

The LHCb detector is a forward spectrometer at the LHC, designed to perform high precision studies of b- and c- hadrons. In Run II of the LHC, a new scheme for the software trigger at LHCb allows splitting the triggering of events into two stages, giving room to perform the alignment and calibration in real time. In the novel detector alignment and calibration strategy for Run II, data collected at the start of the fill are processed in a few minutes and used to update the alignment, while the calibration constants are evaluated for each run. This allows identical constants to be used in the online and offline reconstruction, thus improving the correlation between triggered and offline selected events. The required computing time constraints are met thanks to a new dedicated framework using the multi-core farm infrastructure for the trigger. The larger timing budget, available in the trigger, allows to perform the same track reconstruction online and offline. This enables LHCb to achieve the best reconstruction performance already in the trigger, and allows physics analyses to be performed directly on the data produced by the trigger reconstruction. The novel real-time processing strategy at LHCb is discussed from both the technical and operational point of view. The overall performance of the LHCb detector on the data of Run II is presented as well.

Search for prompt neutrinos with AMANDA-II

Energy Technology Data Exchange (ETDEWEB)

Gozzini, Sara Rebecca

2008-09-11

The investigation performed in this work aims to identify and disentangle the signal of prompt neutrinos from the inclusive atmospheric spectrum. We have analysed data recorded in the years 2000-2003 by the AMANDA-II detector at the geographical South Pole. After a tight event selection, our sample is composed of about 4 . 10{sup 3} atmospheric neutrinos. Prompt neutrinos are decay products of heavy quark hadrons, which are produced in the collision of a cosmic ray particle with a nucleon in the atmosphere. The technique used to recognise prompt neutrinos is based on a simulated information of their energy spectrum, which appears harder than that of the conventional component from light quarks. Models accounting for different hadron production and decay schemes have been included in a Monte Carlo simulation and convoluted with the detector response, in order to reproduce the different spectra. The background of conventional events has been described with the Bartol 2006 tables. The energy spectrum of our data has been reconstructed through a numerical unfolding algorithm. The reconstruction is based on a Monte Carlo simulation and uses as an input three parameters of the neutrino track which are correlated with the energy of the event. Numerical regularisation is introduced to achieve a result free of unphysical oscillations, typical unfortunate feature of unfolding. The reconstructed data spectrum has been compared with different predictions using the model rejection factor technique. The prompt neutrino models differ in the choice of the hadron interaction model, the set of parton distribution functions and the numerical parameterisation of the fragmentation functions describing the transition from quark to hadrons. Here we considered mainly three classes of models, known in the literature as the Recombination Quark Parton Model, the Quark Gluon String Model and the Perturbative QCD model. Upper limits have been set on the expected flux predictions, based on our

Particle combinations in the LHCb Upgrade trigger

CERN Document Server

Zhao, Fanyi

2017-01-01

The LHCb experiment will be upgraded during long shutdown II (2018-2020) to process inelastic proton-proton collisions at 30MHz in a software application and run at a higher instantaneous luminosity of $2\\times 10^{33}cm^{−2}s^{−1}$. Each of these collisions will contain substantially more proton-proton interactions and charged particles. It is important to identify the decay vertices of heavy-flavour hadrons produced by the primary proton-proton interaction in an efficient, CPU-performant manner. In this project, I will learn about the LHCb trigger and experimental programme and investigate alternative models for reconstructing these vertices, which may scale more efficiently to the upgraded trigger conditions than the current model.

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 Run-2 ATLAS Trigger System: Design, Performance and Plan

CERN Document Server

zur Nedden, Martin; The ATLAS collaboration

2016-01-01

In high-energy physics experiments, online selection is crucial to select interesting collisions from the large data volume. The ATLAS experiment at the Large Hadron Collider (LHC) utilizes the trigger system that consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT), reducing the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of about 1000 Hz. In the LHC Run-2 starting from in 2015, the LHC operates at centre-of-mass energy of 13 TeV providing a luminosity up to $1.2 \\cdot 10^{34} {\\rm cm^{-2}s^{-1}}$. The ATLAS trigger system has to cope with these challenges, while maintaining or even improving the efficiency to select relevant physics processes. In this paper, the ATLAS trigger system for LHC Run-2 is reviewed. Secondly, the impressive performance improvements in the HLT trigger algorithms used to identify leptons, hadrons and global event quantities like missing transverse energy is shown. Electron, muon and photon triggers covering trans...

Analysis and realization of a high resolution trigger for DM2 experiment

International Nuclear Information System (INIS)

Bertrand, J.L.

1984-01-01

The construction of a high resolution trigger has been carried out from its theoretical design to building. The term trigger is applied to an almost real-time system for track filtering in particle detection. Curved tracks are detected (with a magnetic field) and the detector is of a revolution symmetry type. The concept of a ''hybrid'' trigger with features in between those of the so-called ''CELLO R0'' and ''MARK II'' types is launched. It allows a positive versatility for the optimization of the different features. Besides a specific structure, some hardware and software implements have been designed for development and tests. The ''TRIGGER LENT'' is presently in operation in the DM2 experiment [fr

The ALICE Dimuon Spectrometer High Level Trigger

CERN Document Server

Becker, B; Cicalo, Corrado; Das, Indranil; de Vaux, Gareth; Fearick, Roger; Lindenstruth, Volker; Marras, Davide; Sanyal, Abhijit; Siddhanta, Sabyasachi; Staley, Florent; Steinbeck, Timm; Szostak, Artur; Usai, Gianluca; Vilakazi, Zeblon

2009-01-01

The ALICE Dimuon Spectrometer High Level Trigger (dHLT) is an on-line processing stage whose primary function is to select interesting events that contain distinct physics signals from heavy resonance decays such as J/psi and Gamma particles, amidst unwanted background events. It forms part of the High Level Trigger of the ALICE experiment, whose goal is to reduce the large data rate of about 25 GB/s from the ALICE detectors by an order of magnitude, without loosing interesting physics events. The dHLT has been implemented as a software trigger within a high performance and fault tolerant data transportation framework, which is run on a large cluster of commodity compute nodes. To reach the required processing speeds, the system is built as a concurrent system with a hierarchy of processing steps. The main algorithms perform partial event reconstruction, starting with hit reconstruction on the level of the raw data received from the spectrometer. Then a tracking algorithm finds track candidates from the recon...

New Media as Software

Directory of Open Access Journals (Sweden)

Manuel Portela

2014-03-01

Full Text Available Review of Lev Manovich, Software Takes Command: Extending the Language of New Media. London: Bloomsbury, 2013, 358 pp. ISBN 978-1-6235-6817-7. In Lev Manovich’s most recent book, this programmatic interrogation of our medial condition leads to the following question: do media still exist after software? This is the question that triggers Manovich’s dialogue both with computing history and with theories of digital media of recent decades, including the extension of his own previous formulations in The Language of New Media, published in 2001, and which became a major reference work in the field. The subtitle of the new book points precisely to this critical revisiting of his earlier work in the context of ubiquitous computing and accelerated transcoding of social, cultural and artistic practices by software.

Trigger Menu-aware Monitoring for the ATLAS experiment

Science.gov (United States)

Hoad, Xanthe; ATLAS Collaboration

2017-10-01

We present a“trigger menu-aware” monitoring system designed for the Run-2 data-taking of the ATLAS experiment at the LHC. Unlike Run-1, where a change in the trigger menu had to be matched by the installation of a new software release at Tier-0, the new monitoring system aims to simplify the ATLAS operational workflows. This is achieved by integrating monitoring updates in a quick and flexible manner via an Oracle DB interface. We present the design and the implementation of the menu-aware monitoring, along with lessons from the operational experience of the new system with the 2016 collision data.

Large scale and performance tests of the ATLAS online software

International Nuclear Information System (INIS)

Alexandrov; Kotov, V.; Mineev, M.; Roumiantsev, V.; Wolters, H.; Amorim, A.; Pedro, L.; Ribeiro, A.; Badescu, E.; Caprini, M.; Burckhart-Chromek, D.; Dobson, M.; Jones, R.; Kazarov, A.; Kolos, S.; Liko, D.; Lucio, L.; Mapelli, L.; Nassiakou, M.; Schweiger, D.; Soloviev, I.; Hart, R.; Ryabov, Y.; Moneta, L.

2001-01-01

One of the sub-systems of the Trigger/DAQ system of the future ATLAS experiment is the Online Software system. It encompasses the functionality needed to configure, control and monitor the DAQ. Its architecture is based on a component structure described in the ATLAS Trigger/DAQ technical proposal. Regular integration tests ensure its smooth operation in test beam setups during its evolutionary development towards the final ATLAS online system. Feedback is received and returned into the development process. Studies of the system behavior have been performed on a set of up to 111 PCs on a configuration which is getting closer to the final size. Large scale and performance test of the integrated system were performed on this setup with emphasis on investigating the aspects of the inter-dependence of the components and the performance of the communication software. Of particular interest were the run control state transitions in various configurations of the run control hierarchy. For the purpose of the tests, the software from other Trigger/DAQ sub-systems has been emulated. The author presents a brief overview of the online system structure, its components and the large scale integration tests and their results

Los ojos de Amanda Berenguer y de Marosa di Giorgio para una exégesis de “El Jardín de las delicias” de El Bosco

Directory of Open Access Journals (Sweden)

Antonella Cancellier

2015-07-01

Full Text Available If in Hieronymus Bosch’s (1453-­‐‑1516 hybrids and metamorphosis Marosa di Giorgio (1932-­‐‑2004 absorbs the most symbolic and disturbing aspects of his “maravilloso negro”, in the same flamish painter Amanda Berenguer (1921-­‐‑2010 finds the inspiration for a subversive discourse. Writings and images enlighten and strengthen each other while the two extraordinary texts of uruguayan literature (Papeles salvajes and Los culos de El Bosco intertwine and converse with triptych of The Garden of Earthly Delights, thus participating in its own complex exegesis.

The new Wide-band Solar Neutrino Trigger for Super-Kamiokande

Science.gov (United States)

Carminati, Giada

Super-Kamiokande observes low energy electrons induced by the elastic scattering of 8B solar neutrinos. The transition region between vacuum and matter oscillations, with neutrino energy near 3 MeV, is still partially unexplored by any detector. Super-Kamiokande can study this intermediate regime adding a new software trigger. The Wide-band Intelligent Trigger (WIT) has been developed to simultaneously trigger and reconstruct very low energy electrons (above 2.49 kinetic MeV) with an e_ciency close to 100%. The WIT system, comprising 256-Hyperthreaded CPU cores and one 10-Gigabit Ethernet network switch, has been recently installed and integrated in the online DAQ system of SK and the complete system is currently in an advanced status of online data testing.

TRIGGER

CERN Multimedia

W. Smith

2012-01-01

  Level-1 Trigger The Level-1 Trigger group is ready to deploy improvements to the L1 Trigger algorithms for 2012. These include new high-PT patterns for the RPC endcap, an improved CSC PT assignment, a new PT-matching algorithm for the Global Muon Trigger, and new calibrations for ECAL, HCAL, and the Regional Calorimeter Trigger. These should improve the efficiency, rate, and stability of the L1 Trigger. The L1 Trigger group also is migrating the online systems to SLC5. To make the data transfer from the Global Calorimeter Trigger to the Global Trigger more reliable and also to allow checking the data integrity online, a new optical link system has been developed by the GCT and GT groups and successfully tested at the CMS electronics integration facility in building 904. This new system is now undergoing further tests at Point 5 before being deployed for data-taking this year. New L1 trigger menus have recently been studied and proposed by Emmanuelle Perez and the L1 Detector Performance Group...

An Overview of the ATLAS High Level Trigger Dataflow and Supervision

CERN Document Server

Wheeler, S; 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; Wengler, T; Werner, P; Wickens, F J; Wiedenmann, W; Wielers, M; Zobernig, G; RT 2003 13th IEEE-NPSS Real Time Conference

2004-01-01

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 (EF). The LVL2 trigger performs event selection with optimized algorithms using selected data guided by Region of Interest pointers provided by the LVL1 trigger. Those events selected by LVL2, are built into complete events, which are passed to the EF for a further stage of event selection and classification using off-line algorithms. Events surviving the EF selection are passed for off-line storage. The two stages of HLT are implemented on processor farms. The concept of distributing the selection process between LVL2 and EF is a key element in the architecture, which allows it to be flexible to changes (luminosity, detector knowledge, background conditions etc.) Although there are some differences in the requirements between these sub-systems there are many commonalities. An overview of the dataflow (event selection) an...

Multiple output timing and trigger generator

Energy Technology Data Exchange (ETDEWEB)

Wheat, Robert M. [Los Alamos National Laboratory; Dale, Gregory E [Los Alamos National Laboratory

2009-01-01

In support of the development of a multiple stage pulse modulator at the Los Alamos National Laboratory, we have developed a first generation, multiple output timing and trigger generator. Exploiting Commercial Off The Shelf (COTS) Micro Controller Units (MCU's), the timing and trigger generator provides 32 independent outputs with a timing resolution of about 500 ns. The timing and trigger generator system is comprised of two MCU boards and a single PC. One of the MCU boards performs the functions of the timing and signal generation (the timing controller) while the second MCU board accepts commands from the PC and provides the timing instructions to the timing controller. The PC provides the user interface for adjusting the on and off timing for each of the output signals. This system provides 32 output or timing signals which can be pre-programmed to be in an on or off state for each of 64 time steps. The width or duration of each of the 64 time steps is programmable from 2 {micro}s to 2.5 ms with a minimum time resolution of 500 ns. The repetition rate of the programmed pulse train is only limited by the time duration of the programmed event. This paper describes the design and function of the timing and trigger generator system and software including test results and measurements.

The Run-2 ATLAS Trigger System: Design, Performance and Plan

CERN Document Server

zur Nedden, Martin; The ATLAS collaboration

2016-01-01

In high-energy physics experiments, online selection is crucial to select interesting collisions from the large data volume. The ATLAS experiment at the Large Hadron Collider (LHC) utilizes the trigger system that consists of a hardware Level-1 (L1) and a software based high-level trigger (HLT), reducing the event rate from the design bunch-crossing rate of 40 MHz to an average recording rate of about 1000 Hz. The ATLAS trigger has been successfully collecting collision data during the first run of the LHC (Run-1) between 2009-2013 at a centre-of-mass energy between 900 GeV and 8 TeV. In the second run of LHC (Run-2) starting from 2015, the LHC operates at centre-of-mass energy of 13 TeV and provides a higher luminosity of collisions. Also, the number of collisions occurring in a same bunch crossing increases. The ATLAS trigger system has to cope with these challenges, while maintaining or even improving the efficiency to select relevant physics processes. In this talk, first we will review the ATLAS trigger ...

A software-based technique enabling composable hierarchical preemptive scheduling for time-triggered applications

NARCIS (Netherlands)

Nejad, A.B.; Molnos, A.; Goossens, K.G.W.

2013-01-01

Many embedded real-time applications are typically time-triggered and preemptive schedulers are used to execute tasks of such applications. Orthogonally, composable partitioned embedded platforms use preemptive time-division multiplexing mechanism to isolate applications. Existing composable systems

ISOTDAQ: another successful trigger and data acquisition school

CERN Multimedia

Antonella Del Rosso

2013-01-01

The fourth ISOTDAQ school was held at the Aristotle University of Thessaloniki (Greece) from 1 to 8 February.   This year, the school received over 70 applications from which the organisers selected 51 participants of 17 different nationalities. The photo shows a tutor and some of the students during the practical exercises. The school, which consists 50% of lectures and 50% of exercises, is a unique opportunity for students to learn how to implement a good trigger and to design a data-acquisition system for today’s increasingly complex experiments. Thanks to the tutored exercises, students can gain hands-on experience of trigger systems, data-acquisition hardware and software, and data-transfer technologies.

The ATLAS High Level Trigger Infrastructure, Performance and Future Developments

CERN Document Server

The ATLAS collaboration

2009-01-01

The ATLAS High Level Trigger (HLT) is a distributed real-time software system that performs the final online selection of events produced during proton-proton collisions at the Large Hadron Collider (LHC). It is designed as a two-stage event filter running on a farm of commodity PC hardware. Currently the system consists of about 850 multi-core processing nodes that will be extended incrementally following the increasing luminosity of the LHC to about 2000 nodes depending on the evolution of the processor technology. Due to the complexity and similarity of the algorithms a large fraction of the software is shared between the online and offline event reconstruction. The HLT Infrastructure serves as the interface between the two domains and provides common services for the trigger algorithms. The consequences of this design choice will be discussed and experiences from the operation of the ATLAS HLT during cosmic ray data taking and first beam in 2008 will be presented. Since the event processing time at the HL...

The CMS High Level Trigger System

CERN Document Server

Afaq, A; Bauer, G; Biery, K; Boyer, V; Branson, J; Brett, A; Cano, E; Carboni, A; Cheung, H; Ciganek, M; Cittolin, S; Dagenhart, W; Erhan, S; Gigi, D; Glege, F; Gómez-Reino, Robert; Gulmini, M; Gutiérrez-Mlot, E; Gutleber, J; Jacobs, C; Kim, J C; Klute, M; Kowalkowski, J; Lipeles, E; Lopez-Perez, Juan Antonio; Maron, G; Meijers, F; Meschi, E; Moser, R; Murray, S; Oh, A; Orsini, L; Paus, C; Petrucci, A; Pieri, M; Pollet, L; Rácz, A; Sakulin, H; Sani, M; Schieferdecker, P; Schwick, C; Sexton-Kennedy, E; Sumorok, K; Suzuki, I; Tsirigkas, D; Varela, J

2007-01-01

The CMS Data Acquisition (DAQ) System relies on a purely software driven High Level Trigger (HLT) to reduce the full Level-1 accept rate of 100 kHz to approximately 100 Hz for archiving and later offline analysis. The HLT operates on the full information of events assembled by an event builder collecting detector data from the CMS front-end systems. The HLT software consists of a sequence of reconstruction and filtering modules executed on a farm of O(1000) CPUs built from commodity hardware. This paper presents the architecture of the CMS HLT, which integrates the CMS reconstruction framework in the online environment. The mechanisms to configure, control, and monitor the Filter Farm and the procedures to validate the filtering code within the DAQ environment are described.

CMS High Level Trigger Timing Measurements

International Nuclear Information System (INIS)

Richardson, Clint

2015-01-01

The two-level trigger system employed by CMS consists of the Level 1 (L1) Trigger, which is implemented using custom-built electronics, and the High Level Trigger (HLT), a farm of commercial CPUs running a streamlined version of the offline CMS reconstruction software. The operational L1 output rate of 100 kHz, together with the number of CPUs in the HLT farm, imposes a fundamental constraint on the amount of time available for the HLT to process events. Exceeding this limit impacts the experiment's ability to collect data efficiently. Hence, there is a critical need to characterize the performance of the HLT farm as well as the algorithms run prior to start up in order to ensure optimal data taking. Additional complications arise from the fact that the HLT farm consists of multiple generations of hardware and there can be subtleties in machine performance. We present our methods of measuring the timing performance of the CMS HLT, including the challenges of making such measurements. Results for the performance of various Intel Xeon architectures from 2009-2014 and different data taking scenarios are also presented. (paper)

CMS Level-1 Upgrade Calorimeter Trigger Prototype Development

CERN Document Server

Klabbers, Pamela Renee

2013-01-01

As the LHC increases luminosity and energy, it will become increasingly difficult to select interesting physics events and remain within the readout bandwidth limitations. An upgrade to the CMS Calorimeter Trigger implementing more complex algorithms is proposed. It utilizes AMC cards with Xilinx FPGAs running in micro-TCA crate with card interconnections via crate backplanes and optical links operating at up to 10 Gbps. Prototype cards with Virtex-6 and Virtex-7 FPGAs have been built and software frameworks for operation and monitoring developed. The physics goals, hardware architectures, and software will be described in this talk. More details can be found in a separate poster at this conference.

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.

The design of a flexible Global Calorimeter Trigger system for the Compact Muon Solenoid experiment

Energy Technology Data Exchange (ETDEWEB)

Brooke, J J [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Cussans, D G [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Frazier, R J E [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Galagedera, S B [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom); Heath, G P [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Huckvale, B J [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Nash, S J [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Newbold, D M [H.H. Wills Physics Lab, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Shah, A A [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)

2007-10-15

We have developed a novel design of triggering system as part of the pipelined hardware Level-1 trigger logic for the CMS experiment at LHC. The Global Calorimeter Trigger is the last element in the processing of calorimeter data, and provides most of the input to the final Level-1 decision. We present the detailed functional requirements for this system. Our design meets the requirements using generic, configurable Trigger Processing Modules built from commercial programmable logic and high-speed serial data links. We describe the hardware, firmware and software components of this solution. CMS has chosen an alternative solution to build the final trigger system; we discuss the implications of our experiences for future development projects along similar lines.

ATLAS Trigger and Data Acquisition Upgrades for High Luminosity LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00439268; The ATLAS collaboration

2016-01-01

The ATLAS experiment at CERN is planning a second phase of upgrades to prepare for the "High Luminosity LHC", a 4th major run due to start in 2026. In order to deliver an order of magnitude more data than previous runs, 14 TeV protons will collide with an instantaneous luminosity of 7.5 × 1034 cm−2s−1, resulting in much higher pileup and data rates than the current experiment was designed to handle. While this extreme scenario is essential to realise the physics programme, it is a huge challenge for the detector, trigger, data acquisition and computing. The detector upgrades themselves also present new requirements and opportunities for the trigger and data acquisition system. Initial upgrade designs for the trigger and data acquisition system are shown, including the real time low latency hardware trigger, hardware-based tracking, the high throughput data acquisition system and the commodity hardware and software-based data handling and event filtering. The motivation, overall architecture and expected ...

ATLAS Trigger and Data Acquisition Upgrades for High Luminosity LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00421104; The ATLAS collaboration

2016-01-01

The ATLAS experiment at CERN is planning a second phase of upgrades to prepare for the "High Luminosity LHC", a 4th major run due to start in 2026. In order to deliver an order of magnitude more data than previous runs, 14 TeV protons will collide with an instantaneous luminosity of $7.5 \\times 10^{34} cm^{-2}s^{-1}$, resulting in much higher pileup and data rates than the current experiment was designed to handle. While this extreme scenario is essential to realise the physics programme, it is a huge challenge for the detector, trigger, data acquisition and computing. The detector upgrades themselves also present new requirements and opportunities for the trigger and data acquisition system. Initial upgrade designs for the trigger and data acquisition system are shown, including the real time low latency hardware trigger, hardware-based tracking, the high throughput data acquisition system and the commodity hardware and software-based data handling and event filtering. The motivation, overall architecture an...

ATLAS Trigger and Data Acquisition Upgrades for High Luminosity LHC

CERN Document Server

George, Simon; The ATLAS collaboration

2016-01-01

The ATLAS experiment at CERN is planning a second phase of upgrades to prepare for the "High Luminosity LHC", a 4th major run due to start in 2026. In order to deliver an order of magnitude more data than previous runs, 14 TeV protons will collide with an instantaneous luminosity of 7.5 × 10^{34} cm^{−2}s^{−1}, resulting in much higher pileup and data rates than the current experiment was designed to handle. While this extreme scenario is essential to realise the physics programme, it is a huge challenge for the detector, trigger, data acquisition and computing. The detector upgrades themselves also present new requirements and opportunities for the trigger and data acquisition system. Initial upgrade designs for the trigger and data acquisition system are shown, including the real time low latency hardware trigger, hardware-based tracking, the high throughput data acquisition system and the commodity hardware and software-based data handling and event filtering. The motivation, overall architecture and ...

ATLAS Trigger and Data Acquisition Upgrades for High Luminosity LHC

CERN Document Server

Balunas, William Keaton; The ATLAS collaboration

2016-01-01

The ATLAS experiment at CERN is planning a second phase of upgrades to prepare for the "High Luminosity LHC", a 4th major run due to start in 2026. In order to deliver an order of magnitude more data than previous runs, 14 TeV protons will collide with an instantaneous luminosity of $7.5 × 10^{34}$ cm$^{−2}$s$^{−1}$, resulting in much higher pileup and data rates than the current experiment was designed to handle. While this extreme scenario is essential to realise the physics programme, it is a huge challenge for the detector, trigger, data acquisition and computing. The detector upgrades themselves also present new requirements and opportunities for the trigger and data acquisition system. Initial upgrade designs for the trigger and data acquisition system are shown, including the real time low latency hardware trigger, hardware-based tracking, the high throughput data acquisition system and the commodity hardware and software-based data handling and event filtering. The motivation, overall architectur...

FTK status and track triggers in ATLAS at HL-LHC

CERN Document Server

ATLAS Collaboration; The ATLAS collaboration

2016-01-01

The expected instantaneous luminosities delivered by the Large Hadron Collider will place continually increasing burdens on the trigger systems of the ATLAS detector. The use of tracking information is key to maintaining a manageable trigger rate while keeping a high efficiency. At the same time, however, track finding is one of the more resource-intensive tasks in the software-based processing farms of the high level trigger system. To support the trigger, ATLAS is building and currently installing the Fast TracK Finder (FTK), a hardware-based system that uses massively parallel pattern recognition in Associative Memory to reconstruct tracks above transverse momenta of 1 GeV across the entire detector at 100 kHz with a latency of ~100 microseconds. In the first-stage of track finding, FTK compares hits in ATLAS silicon detectors against ~1 billion pre-computed track pattern candidates. Track parameters for these candidates, including goodness-of-fit tests, are calculated in FPGAs using a linear approximation...

A hardware fast tracker for the ATLAS trigger

Science.gov (United States)

Asbah, Nedaa

2016-09-01

The trigger system of the ATLAS experiment is designed to reduce the event rate from the LHC nominal bunch crossing at 40 MHz to about 1 kHz, at the design luminosity of 1034 cm-2 s-1. After a successful period of data taking from 2010 to early 2013, the LHC already started with much higher instantaneous luminosity. This will increase the load on High Level Trigger system, the second stage of the selection based on software algorithms. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals. The Fast TracKer (FTK) is part of the ATLAS trigger upgrade project. It is a hardware processor that will provide, at every Level-1 accepted event (100 kHz) and within 100 microseconds, full tracking information for tracks with momentum as low as 1 GeV. Providing fast, extensive access to tracking information, with resolution comparable to the offline reconstruction, FTK will help in precise detection of the primary and secondary vertices to ensure robust selections and improve the trigger performance. FTK exploits hardware technologies with massive parallelism, combining Associative Memory ASICs, FPGAs and high-speed communication links.

LHCb-The LHCb trigger in Run II

CERN Multimedia

Michielin, Emanuele

2016-01-01

The LHCb trigger system has been upgraded to exploit the real-time alignment, calibration and analysis capabilities of LHCb in Run-II. An increase in the CPU and disk capacity of the event filter farm, combined with improvements to the reconstruction software, mean that efficient, exclusive selections can be made in the first stage of the High Level Trigger (HLT1). The output of HLT1 is buffered to the 5 PB of disk on the event filter farm, while the detector is aligned and calibrated in real time. The second stage, HLT2, performs complete, offline quality, event reconstruction. Physics analyses can be performed directly on this information, and for the majority of charm physics selections, a reduced event format can be written out, which permits higher event rates.

TRIGGER

CERN Multimedia

Roberta Arcidiacono

2013-01-01

Trigger Studies Group (TSG) The Trigger Studies Group has just concluded its third 2013 workshop, where all POGs presented the improvements to the physics object reconstruction, and all PAGs have shown their plans for Trigger development aimed at the 2015 High Level Trigger (HLT) menu. The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for Trigger menu development, path timing, Trigger performance studies coordination, HLT offline DQM as well as HLT release, menu and conditions validation – this last task in collaboration with PdmV (Physics Data and Monte Carlo Validation group). In the last months the group has delivered several HLT rate estimates and comparisons, using the available data and Monte Carlo samples. The studies were presented at the Trigger workshops in September and December, and STEAM has contacted POGs and PAGs to understand the origin of the discrepancies observed between 8 TeV data and Monte Carlo simulations. The most recent results show what the...

Design and Development of a Graphical Setup Software for the CMS Global Trigger

CERN Document Server

Glaser, P; Bergauer, H; Padrta, M; Taurok,A; Wulz, C E

2006-01-01

The CMS experiment at CERNs Large Hadron Collider will search for new physics at high energies. Its trigger system is an essential component in the selection process of potentially interesting events. The Global Trigger is the final stage of the first-level selection process. It is implemented as a complex electronic system containing logic devices, which need to be programmed according to physics requirements. It has to reject or accept events for further processing based on coarse measurements of particle properties such as energies, momenta and location. Algorithms similar to the ones used in the physics analysis are executed in parallel during the event selection process. A graphical setup program to define these algorithms and to subsequently configure the hardware has been developed. The design and implementation of the program, guided by the principal requirements of flexibility, quality assurance, platform-independence and extensibility, are described.

Fully Employing Software Inspections Data

Science.gov (United States)

Shull, Forrest; Feldmann, Raimund L.; Seaman, Carolyn; Regardie, Myrna; Godfrey, Sally

2009-01-01

Software inspections provide a proven approach to quality assurance for software products of all kinds, including requirements, design, code, test plans, among others. Common to all inspections is the aim of finding and fixing defects as early as possible, and thereby providing cost savings by minimizing the amount of rework necessary later in the lifecycle. Measurement data, such as the number and type of found defects and the effort spent by the inspection team, provide not only direct feedback about the software product to the project team but are also valuable for process improvement activities. In this paper, we discuss NASA's use of software inspections and the rich set of data that has resulted. In particular, we present results from analysis of inspection data that illustrate the benefits of fully utilizing that data for process improvement at several levels. Examining such data across multiple inspections or projects allows team members to monitor and trigger cross project improvements. Such improvements may focus on the software development processes of the whole organization as well as improvements to the applied inspection process itself.

Drift Tubes Trigger System of the CMS Experiment at LHC : Commissioning and Performances

CERN Document Server

Battilana, Carlo

2009-01-01

In this thesis the performances of the CMS Drift Tubes Local Trigger System of the CMS detector are studied. CMS is one of the general purpose experiments that will operate at the Large Hadron Collider at CERN. Results from data collected during the Cosmic Run At Four Tesla (CRAFT) commissioning exercise, a globally coordinated run period where the full experiment was involved and configured to detect cosmic rays crossing the CMS cavern, are presented. These include analyses on the precision and accuracy of the trigger reconstruction mechanism and measurement of the trigger efficiency. The description of a method to perform system synchronization is also reported, together with a comparison of the outcomes of trigger electronics and its software emulator code.

Software for the LHCb experiment

CERN Document Server

Corti, Gloria; Belyaev, Ivan; Cattaneo, Marco; Charpentier, Philippe; Frank, Markus; Koppenburg, Patrick; Mato-Vila, P; Ranjard, Florence; Roiser, Stefan

2006-01-01

LHCb is an experiment for precision measurements of CP-violation and rare decays in B mesons at the LHC collider at CERN. The LHCb software development strategy follows an architecture-centric approach as a way of creating a resilient software framework that can withstand changes in requirements and technology over the expected long lifetime of the experiment. The software architecture, called GAUDI, supports event data processing applications that run in different processing environments ranging from the real-time high- level triggers in the online system to the final physics analysis performed by more than one hundred physicists. The major architectural design choices and the arguments that lead to these choices will be outlined. Object oriented technologies have been used throughout. Initially developed for the LHCb experiment, GAUDI has been adopted and extended by other experiments. Several iterations of the GAUDI software framework have been released and are now being used routinely by the physicists of...

Klystron control software in the SLC

International Nuclear Information System (INIS)

Jobe, R.K.; Thompson, K.; Phinney, N.

1985-05-01

Triggering, control, and monitoring of 240 high-power klystrons will be supported by the SLC control system this summer. The control software is distributed among a VAX host computer, a local microprocessor cluster, and a dedicated intelligent CAMAC module. The functions performed by these three components and the algorithms used are discussed

Real time data analysis with the ATLAS Trigger at the LHC in Run-2

CERN Document Server

Beauchemin, Pierre-Hugues; The ATLAS collaboration

2018-01-01

The trigger selection capabilities of the ATLAS detector have been significantly enhanced for the LHC Run- 2 in order to cope with the higher event rates and with the large number of simultaneous interactions (pile-up) per protonproton bunch crossing. A new hardware system, designed to analyse real time event-topologies at Level-1 came to full use in 2017. A hardware-based track reconstruction system, expected to be used real-time in 2018, is designed to provide track information to the high-level software trigger at its full input rate. The high-level trigger selections are largely relying on offline-like reconstruction techniques, and in some cases multivariate analysis methods. Despite the sudden change in LHC operations during the second half of 2017, which caused an increase in pile-up and therefore also in CPU usage of the trigger algorithms, the set of triggers (so called trigger menu) running online has undergone only minor modifications thanks to the robustness and redundancy of the trigger system, a...

Tracking and flavour tagging selection in the ATLAS High Level Trigger

CERN Document Server

Calvetti, Milene; The ATLAS collaboration

2017-01-01

In high-energy physics experiments, track based selection in the online environment is crucial for the detection of physics processes of interest for further study. This is of particular importance at the Large Hadron Collider (LHC), where the increasingly harsh collision environment is challenging participating experiments to improve the performance of their online selection. Principle among these challenges is the increasing number of interactions per bunch crossing, known as pileup. In the ATLAS experiment the challenge has been addressed with multiple strategies. Firstly, individual trigger groups focusing on specific physics objects have implemented novel algorithms which make use of the detailed tracking and vertexing performed within the trigger to improve rejection without losing efficiency. Secondly, since 2015 all trigger areas have also benefited from a new high performance inner detector software tracking system implemented in the High Level Trigger. Finally, performance will be further enhanced i...

The data-acquisition and second level trigger system for the ZEUS calorimeter

International Nuclear Information System (INIS)

Lugt, H.J. van der.

1993-01-01

ZEUS and HERA are introduced in chapter 1 with emphasis on the ZEUS Calorimeter and the ZEUS trigger system. The analog and digital electronics developed for the readout of the Calorimeter signals, and the hardware for the Calorimeter Second Level Trigger and data-acquisition system, is described in chapter 2. Emphasis is put on the hardware developed at NIKHEF, which is based on the transputer as the main processing element. The ZEUS trigger and data-acquisition environment as well as the calibration procedures needed for the Calorimeter impose several requirements on the design of the data-acquisition system. The requirements, their implications for the design of the transputer network architecture and the design itself, are described in detail in chapter 3. The software developed for the Calorimeter data-acquisition is described in chapter 4. It includes both the software for the Calorimeter data-acquisition as that required for the calibration of the Calorimeter. First experiences with the CAL-SLT algorithms, obtained during the 1992 HERA running periods, are presented in chapter 5. Chapter 6 discusses the performance of the Calorimeter data-acquisition system. (orig.)

TRIGGER

CERN Multimedia

Wesley Smith

Trigger Hardware The status of the trigger components was presented during the September CMS Week and Annual Review and at the monthly trigger meetings in October and November. Procedures for cold and warm starts (e.g. refreshing of trigger parameters stored in registers) of the trigger subsystems have been studied. Reviews of parts of the Global Calorimeter Trigger (GCT) and the Global Trigger (GT) have taken place in October and November. The CERN group summarized the status of the Trigger Timing and Control (TTC) system. All TTC crates and boards are installed in the underground counting room, USC55. The central clock system will be upgraded in December (after the Global Run at the end of November GREN) to the new RF2TTC LHC machine interface timing module. Migration of subsystem's TTC PCs to SLC4/ XDAQ 3.12 is being prepared. Work is on going to unify the access to Local Timing Control (LTC) and TTC CMS interface module (TTCci) via SOAP (Simple Object Access Protocol, a lightweight XML-based messaging ...

GPUs for fast triggering and pattern matching at the CERN experiment NA62

International Nuclear Information System (INIS)

Lamanna, Gianluca; Collazuol, Gianmaria; Sozzi, Marco

2011-01-01

In rare decays experiments an effective trigger is crucial to reduce both the quantity of data written on tape and the bandwidth requirements for the DAQ (Data Acquisition) system. A multilevel architecture is commonly used to achieve a higher reduction factor, exploiting dedicated custom hardware and flexible software in standard computers. In this paper we discuss the possibility to use commercial video card processors (GPU) to build a fast and effective trigger system, both at hardware and software level. The case of fast pattern matching in the RICH detector of the NA62 experiment at CERN aiming at measuring the Branching Ratio of the ultra rare decay K + →π + νν-bar is considered as use case although the versatility and the customizability of this approach easily allow exporting the concept to different contexts.

Evolution of the Trigger and Data Acquisition System in the ATLAS experiment

CERN Document Server

Kama, Sami; The ATLAS collaboration

2012-01-01

The ATLAS detector is designed to observe proton-proton collisions delivered by the LHC accelerator. The ATLAS Trigger and Data Acquisition (TDAQ) system is responsible for the selection and the conveyance of physics data, reducing the rate of stored events from the initial 40 MHz LHC frequency to several hundreds Hz. The TDAQ system is organised in a three-level selection scheme, including a hardware-based first-level trigger and second- and third-level triggers implemented as software systems distributed on commodity hardware nodes. The second-level trigger operates over limited regions of the detector, the so-called Regions-of-Interest (RoI). The last selection step deals instead with complete events. In the current design, the second and third trigger levels are separate systems. While this architecture was successfully operated well beyond the original design goals, the accumulated experience stimulated interest to explore possible evolutions. One attractive direction is to merge the second and third tri...

Evolution of the Trigger and Data Acquisition System in the ATLAS experiment

CERN Document Server

Kama, S; The ATLAS collaboration

2012-01-01

The ATLAS detector is designed to observe proton-proton collisions delivered by the LHC accelerator. The ATLAS Trigger and Data Acquisition (TDAQ) system is responsible for the selection and the conveyance of physics data, reducing the rate of stored events from the initial $40\\MHz$ LHC frequency to several hundreds Hz. The TDAQ system is organized in a three-level selection scheme, including a hardware-based first-level trigger and second- and third-level triggers implemented as software systems distributed on commodity hardware nodes. The second-level trigger operates over limited regions of the detector, the so-called Regions-of-Interest (RoI). The last selection step deals instead with complete events. In the current design, the second and third trigger levels are separate systems. While this architecture was successfully operated well beyond the original design goals, the accumulated experience stimulated interest to explore possible evolutions. One attractive direction is to merge the second and third t...

ATLAS Trigger Monitoring and Operation in Proton Proton Collisions at 900 GeV

CERN Document Server

zur Nedden, M; The ATLAS collaboration

2010-01-01

The trigger of the ATLAS-experiment is build as a three level system. The first level is realized in hardware while the higher levels (HLT) are pure software implemented triggers based on large PC farms. According to the LHC bunch crossing frequency of 40 MHz and the expectation of up to 23 interactions per bunch crossing at design luminosity, the trigger system must be able to deal with an input rate of 1 GHz whereas the maximum storage rate is 200 Hz. This complex data acquisition and trigger system requires a reliable and redundant diagnostic and monitoring system. This is inevitable for a successful commissioning and stable running of the whole experiment. The main aspects of trigger monitoring are the rate measurements at each step of the trigger decision at each level, the determination of the quality of the physics objects candidates to be selected at trigger level (as candidates for electrons, muons, taus, gammas, jets, b-jets and missing energy) and the supervision of the system's behavior during the...

OCL2Trigger: Deriving active mechanisms for relational databases using Model-Driven Architecture

OpenAIRE

Al-Jumaily, Harith T.; Cuadra, Dolores; Martínez, Paloma

2008-01-01

16 pages, 10 figures.-- Issue title: "Best papers from the 2007 Australian Software Engineering Conference (ASWEC 2007), Melbourne, Australia, April 10-13, 2007, Australian Software Engineering Conference 2007". Transforming integrity constraints into active rules or triggers for verifying database consistency produces a serious and complex problem related to real time behaviour that must be considered for any implementation. Our main contribution to this work is to provide a complete appr...

Verification steps for the CMS event-builder software

CERN Multimedia

CERN. Geneva

2015-01-01

The CMS event-builder software is used to assemble event fragments into complete events at 100 kHz. The data originates at the detector front-end electronics, passes through several computers and is transported from the underground to the high-level trigger farm on the surface. I will present the testing and verifications steps a new software version has to pass before it is deployed in production. I will discuss the current practice and possible improvements.

Trigger Algorithms for Alignment and Calibration at the CMS Experiment

CERN Document Server

Fernandez Perez Tomei, Thiago Rafael

2017-01-01

The data needs of the Alignment and Calibration group at the CMS experiment are reasonably different from those of the physics studies groups. Data are taken at CMS through the online event selection system, which is implemented in two steps. The Level-1 Trigger is implemented on custom-made electronics and dedicated to analyse the detector information at a coarse-grained scale, while the High Level Trigger (HLT) is implemented as a series of software algorithms, running in a computing farm, that have access to the full detector information. In this paper we describe the set of trigger algorithms that is deployed to address the needs of the Alignment and Calibration group, how it fits in the general infrastructure of the HLT, and how it feeds the Prompt Calibration Loop (PCL), allowing for a fast turnaround for the alignment and calibration constants.

The ATLAS TDAQ DataCollection Software

CERN Document Server

Haeberli, C; Pretzl, K

2003-01-01

The Large Hadron Collider, which is currently under construction at CERN near Geneva, will collide protons with a center-of-mass energy of 14TeV. This high energy offers the possibility to discover particles with masses on the TeV scale. Bunches of 1.15 10^11 protons will cross at a rate of 40 MHz. 23 proton-proton collisions will happen at every bunch-crossing, which results in a total proton-proton interaction rate of almost one GHz. The biggest part of these interactions do not contain new physics but mostly QCD background. Therefore the detectors to discovery physics, such as ATLAS, need to select the ~100 bunch-crossings with the biggest discovery potential out of the 40 10^6 bunch-crossings per second. In case of the ATLAS experiment this reduction will be achieved on a three level trigger system. The first level trigger runs on custom hardware, the two higher trigger levels run as software algorithms on farms of hundreds of commodity PCs. The second level trigger will run at a rate of up to 100 kHz on ...

ISOTDAQ - where students learn about trigger and data acquisition

CERN Multimedia

CERN Bulletin

2011-01-01

Where can students learn to implement a good trigger and to design the data acquisition system for today’s increasingly complex experiments? Universities rarely include classes on such specific topics. The ISOTDAQ School trains students and helps them gain hands-on experience of trigger systems, data-acquisition hardware and software, and data-transfer technologies.   One of the commercially available FPGA development boards from Altera. This was used in one of the practical exercises at ISOTDAQ2011 to teach students the principles of FPGA programming. The second International School of Trigger and Data Acquisition (ISOTDAQ) was held from 9 to 16 February at the Physics Department of Rome University, ‘La Sapienza’. The School was jointly organised and sponsored by CERN, INFN, ACEOLE (a Marie Curie Initial Training Network at CERN), and National Instruments. This year almost fifty students took part in the School. “Leading experts in the field gave lectures ...

A Hardware Fast Tracker for the ATLAS trigger

International Nuclear Information System (INIS)

Asbah, N.

2016-01-01

The trigger system of the ATLAS experiment is designed to reduce the event rate from the LHC nominal bunch crossing at 40 MHz to about 1 kHz, at the design luminosity of 10 34 cm -2 · s -1 . After a successful period of data taking from 2010 to early 2013, the LHC already started with much higher instantaneous luminosity. This will increase the load on High Level Trigger system, the second stage of the selection based on software algorithms. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals. The Fast TracKer (FTK) is part of the ATLAS trigger upgrade project. It is a hardware processor that will provide, at every Level-1 accepted event (100 kHz) and within 100 μs, full tracking information for tracks with momentum as low as 1 GeV. Providing fast, extensive access to tracking information, with resolution comparable to the offline reconstruction, FTK will help in precise detection of the primary and secondary vertices to ensure robust selections and improve the trigger performance. FTK exploits hardware technologies with massive parallelism, combining Associative Memory ASICs, FPGAs and high-speed communication links.

TRIGGER

CERN Multimedia

R. Carlin with contributions from D. Acosta

2012-01-01

Level-1 Trigger Data-taking continues at cruising speed, with high availability of all components of the Level-1 trigger. We have operated the trigger up to a luminosity of 7.6E33, where we approached 100 kHz using the 7E33 prescale column.  Recently, the pause without triggers in case of an automatic "RESYNC" signal (the "settle" and "recover" time) was reduced in order to minimise the overall dead-time. This may become very important when the LHC comes back with higher energy and luminosity after LS1. We are also preparing for data-taking in the proton-lead run in early 2013. The CASTOR detector will make its comeback into CMS and triggering capabilities are being prepared for this. Steps to be taken include improved cooperation with the TOTEM trigger system and using the LHC clock during the injection and ramp phases of LHC. Studies are being finalised that will have a bearing on the Trigger Technical Design Report (TDR), which is to be rea...

LHCb: The LHCb Trigger Architecture beyond LS1

CERN Multimedia

Albrecht, J; Neubert, S; Raven, G; Sokoloff, M D; Williams, M

2013-01-01

The LHCb experiment is a spectrometer dedicated to the study of heavy flavor at the LHC. The rate of proton-proton collisions at the LHC is 15 MHz, but resource limitations mean that only 5 kHz can be written to storage for offline analytsis. For this reason the LHCb data acquisition system -- trigger -- plays a key role in selecting signal events and rejecting background. In contrast to previous experiments at hadron colliders like for example CDF or D0, the bulk of the LHCb trigger is implemented in software and deployed on a farm of 20k parallel processing nodes. This system, called the High Level Trigger (HLT) is responsible for reducing the rate from the maximum at which the detector can be read out, 1.1 MHz, to the 5 kHz which can be processed offline,and has 20 ms in which to process and accept/reject each event. In order to minimize systematic uncertainties, the HLT was designed from the outset to reuse the offline reconstruction and selection code. During the long shutdown it is proposed to extend th...

A Hardware Fast Tracker for the ATLAS trigger

CERN Document Server

Asbah, Nedaa; The ATLAS collaboration

2015-01-01

The trigger system of the ATLAS experiment is designed to reduce the event rate from the LHC nominal bunch crossing at 40 MHz to about 1 kHz, at the design luminosity of 10^{34} cm^{-2}s^{-1}. After a successful period of data taking from 2010 to early 2013, the LHC restarted with much higher instantaneous luminosity. This will increase the load on High Level Trigger system, the second stage of the selection based on software algorithms. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals. The Fast TracKer (FTK) is part of the ATLAS trigger upgrade project; it is a hardware processor that will provide, at every level-1 accepted event (100 kHz) and within 100 microseconds, full tracking information for tracks with momentum as low as 1 GeV. Providing fast extensive access to tracking information, with resolution comparable to the offline reconstruction, FTK will help in precise detection of the primary and secondar...

How Open Source Has Changed the Software Industry: Perspectives from Open Source Entrepreneurs

OpenAIRE

Lindman, Juho; Rajala, Risto

2012-01-01

The emergence of F/LOSS (free/libre open source software) has triggered several changes in the software industry. F/LOSS has been cited as an archetypal form of open innovation; it consists of the convergence and collaboration of like-minded parties. An increasing number of software firms have taken upon this approach to link outsiders into their service development and product design. Also, software firms have been increasingly grounded their business models on user-centric and service-orien...

The CMS Level-1 tau lepton and Vector Boson Fusion triggers for the LHC Run II

CERN Document Server

Amendola, Chiara

2017-01-01

The CMS experiment implements a sophisticated two-level triggering system composed of Level-1, instrumented by custom-design hardware boards, and a software High-Level-Trigger. A new Level-1 trigger architecture with improved performance is now being used to maintain the thresholds that were used in LHC Run I for the more challenging luminosity conditions experienced during Run II. The upgrades to the calorimetry trigger will be described along with performance data. The algorithms for the selection of final states with tau leptons, both for precision measurements and for searches of new physics beyond the Standard Model, will be described in detail. The implementation of the first dedicated Vector Boson Fusion trigger algorithm will be presented as well, along with its performance on benchmark physics signals.

The evolution of the Trigger and Data Acquisition System in the ATLAS experiment

CERN Document Server

Krasznahorkay, A; The ATLAS collaboration

2013-01-01

The ATLAS experiment, aimed at recording the results of LHC proton-proton collisions, is upgrading its Trigger and Data Acquisition (TDAQ) system during the current LHC first long shutdown. The purpose of such upgrade is to add robustness and flexibility to the selection and the conveyance of the physics data, simplify the maintenance of the infrastructure, exploit new technologies and, overall, make ATLAS data-taking capable of dealing with increasing event rates. The TDAQ system used to date is organised in a three-level selection scheme, including a hardware-based first-level trigger and second- and third-level triggers implemented as separate software systems distributed on commodity hardware nodes. The second-level trigger operates over limited regions of the detector, the so-called Regions-of-Interest (RoI). The third-level trigger deals instead with complete events. While this architecture was successfully operated well beyond the original design goals, the accumulated experience stimulated interest to...

Real time data analysis with the ATLAS trigger at the LHC in Run-2

CERN Document Server

Beauchemin, Pierre-Hugues; The ATLAS collaboration

2018-01-01

The trigger selection capabilities of the ATLAS detector have been significantly enhanced for the LHC Run-2 in order to cope with the higher event rates and with the large number of simultaneous interactions (pile-up) per proton-proton bunch crossing. A new hardware system, designed to analyse real time event-topologies at Level-1 came to full use in 2017. A hardware-based track reconstruction system, expected to be used real-time in 2018, is designed to provide track information to the high-level software trigger at its full input rate. The high-level trigger selections are largely relying on offline-like reconstruction techniques, and in some cases multi-variate analysis methods. Despite the sudden change in LHC operations during the second half of 2017, which caused an increase in pile-up and therefore also in CPU usage of the trigger algorithms, the set of triggers (so called trigger menu) running online has undergone only minor modifications thanks to the robustness and redundancy of the trigger system, ...

Overcoming public speaking anxiety of software engineers using virtual reality exposure therapy.

OpenAIRE

Nazligul, Merve Denizc; Yilmaz, Murat; Gulec, Ulas; Ali Gozcu, Mert; O'Connor, Rory; Clarke, Paul

2017-01-01

Public speaking anxiety is a type of social phobia, which might be commonly seen in novice software engineers. It is usually triggered by a fear of social performance especially when the performer is unfamiliar with the audience. Today, many software engineering activities (e.g. code inspection, peer review, daily meetings, etc.) require social gatherings where individuals need to present their work. However, novice software engineers may not be able to reduce their performance anxiety during...

Interconnection test framework for the CMS level-1 trigger system

International Nuclear Information System (INIS)

Hammer, J.; Magrans de Abril, M.; Wulz, C.E.

2012-01-01

The Level-1 Trigger Control and Monitoring System is a software package designed to configure, monitor and test the Level-1 Trigger System of the Compact Muon Solenoid (CMS) experiment at CERN's Large Hadron Collider. It is a large and distributed system that runs over 50 PCs and controls about 200 hardware units. The objective of this paper is to describe and evaluate the architecture of a distributed testing framework - the Interconnection Test Framework (ITF). This generic and highly flexible framework for creating and executing hardware tests within the Level-1 Trigger environment is meant to automate testing of the 13 major subsystems interconnected with more than 1000 links. Features include a web interface to create and execute tests, modeling using finite state machines, dependency management, automatic configuration, and loops. Furthermore, the ITF will replace the existing heterogeneous testing procedures and help reducing both maintenance and complexity of operation tasks. (authors)

Flexible trigger menu implementation on the Global Trigger for the CMS Level-1 trigger upgrade

Science.gov (United States)

MATSUSHITA, Takashi; CMS Collaboration

2017-10-01

The CMS experiment at the Large Hadron Collider (LHC) has continued to explore physics at the high-energy frontier in 2016. The integrated luminosity delivered by the LHC in 2016 was 41 fb-1 with a peak luminosity of 1.5 × 1034 cm-2s-1 and peak mean pile-up of about 50, all exceeding the initial estimations for 2016. The CMS experiment has upgraded its hardware-based Level-1 trigger system to maintain its performance for new physics searches and precision measurements at high luminosities. The Global Trigger is the final step of the CMS Level-1 trigger and implements a trigger menu, a set of selection requirements applied to the final list of objects from calorimeter and muon triggers, for reducing the 40 MHz collision rate to 100 kHz. The Global Trigger has been upgraded with state-of-the-art FPGA processors on Advanced Mezzanine Cards with optical links running at 10 GHz in a MicroTCA crate. The powerful processing resources of the upgraded system enable implementation of more algorithms at a time than previously possible, allowing CMS to be more flexible in how it handles the available trigger bandwidth. Algorithms for a trigger menu, including topological requirements on multi-objects, can be realised in the Global Trigger using the newly developed trigger menu specification grammar. Analysis-like trigger algorithms can be represented in an intuitive manner and the algorithms are translated to corresponding VHDL code blocks to build a firmware. The grammar can be extended in future as the needs arise. The experience of implementing trigger menus on the upgraded Global Trigger system will be presented.

Large Scale Software Building with CMake in ATLAS

CERN Document Server

Elmsheuser, Johannes; The ATLAS collaboration; Obreshkov, Emil; Undrus, Alexander

2016-01-01

The offline software of the ATLAS experiment at the LHC (Large Hadron Collider) serves as the platform for detector data reconstruction, simulation and analysis. It is also used in the detector trigger system to select LHC collision events during data taking. ATLAS offline software consists of several million lines of C++ and Python code organized in a modular design of more than 2000 specialized packages. Because of different workflows many stable numbered releases are in parallel production use. To accommodate specific workflow requests, software patches with modified libraries are distributed on top of existing software releases on a daily basis. The different ATLAS software applications require a flexible build system that strongly supports unit and integration tests. Within the last year this build system was migrated to CMake. A CMake configuration has been developed that allows one to easily set up and build the mentioned software packages. This also makes it possible to develop and test new and modifi...

Large scale software building with CMake in ATLAS

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00218447; The ATLAS collaboration; Elmsheuser, Johannes; Obreshkov, Emil; Undrus, Alexander

2017-01-01

The offline software of the ATLAS experiment at the LHC (Large Hadron Collider) serves as the platform for detector data reconstruction, simulation and analysis. It is also used in the detector trigger system to select LHC collision events during data taking. ATLAS offline software consists of several million lines of C++ and Python code organized in a modular design of more than 2000 specialized packages. Because of different workflows many stable numbered releases are in parallel production use. To accommodate specific workflow requests, software patches with modified libraries are distributed on top of existing software releases on a daily basis. The different ATLAS software applications require a flexible build system that strongly supports unit and integration tests. Within the last year this build system was migrated to CMake. A CMake configuration has been developed that allows one to easily set up and build the mentioned software packages. This also makes it possible to develop and test new and modifi...

The ATLAS muon trigger: Experience and performance in the first 3 years of LHC pp runs

International Nuclear Information System (INIS)

Ventura, Andrea

2013-01-01

The ATLAS experiment at CERN's Large Hadron Collider (LHC) deploys a three-level processing scheme for the trigger system. The Level-1 muon trigger system gets its input from fast muon trigger detectors. Sector logic boards select muon candidates, which are passed via an interface board to the central trigger processor and then to the High Level Trigger (HLT). The muon HLT is purely software based and encompasses a Level-2 trigger followed by an event filter for a staged trigger approach. It has access to the data of the precision muon detectors and other detector elements to refine the muon hypothesis. The ATLAS experiment has taken data with high efficiency continuously over entire running periods from 2010 to 2012, for which sophisticated triggers to guard the highest physics output while reducing effectively the event rate were mandatory. The ATLAS muon trigger has successfully adapted to this challenging environment. The selection strategy has been optimized for the various physics analyses involving muons in the final state. This work briefly summarizes these three years of experience in the ATLAS muon trigger and reports about efficiency, resolution, and general performance of the muon trigger

TRIGGER

CERN Multimedia

W. Smith, from contributions of D. Acosta

2012-01-01

  The L1 Trigger group deployed several major improvements this year. Compared to 2011, the single-muon trigger rate has been reduced by a factor of 2 and the η coverage has been restored to 2.4, with high efficiency. During the current technical stop, a higher jet seed threshold will be applied in the Global Calorimeter Trigger in order to significantly reduce the strong pile-up dependence of the HT and multi-jet triggers. The currently deployed L1 menu, with the “6E33” prescales, has a total rate of less than 100 kHz and operates with detector readout dead time of less than 3% for luminosities up to 6.5 × 1033 cm–2s–1. Further prescale sets have been created for 7 and 8 × 1033 cm–2s–1 luminosities. The L1 DPG is evaluating the performance of the Trigger for upcoming conferences and publication. Progress on the Trigger upgrade was reviewed during the May Upgrade Week. We are investigating scenarios for stagin...

TRIGGER

CERN Multimedia

R. Arcidiacono

2013-01-01

  In 2013 the Trigger Studies Group (TSG) has been restructured in three sub-groups: STEAM, for the development of new HLT menus and monitoring their performance; STORM, for the development of HLT tools, code and actual configurations; and FOG, responsible for the online operations of the High Level Trigger. The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for Trigger Menu development, path timing, trigger performance studies coordination, HLT offline DQM as well as HLT release, menu and conditions validation – in collaboration and with the technical support of the PdmV group. Since the end of proton-proton data taking, the group has started preparing for 2015 data taking, with collisions at 13 TeV and 25 ns bunch spacing. The reliability of the extrapolation to higher energy is being evaluated comparing the trigger rates on 7 and 8 TeV Monte Carlo samples with the data taken in the past two years. The effect of 25 ns bunch spacing is being studied on the d...

Distributed control and monitoring of high-level trigger processes on the LHCb online farm

CERN Document Server

Vannerem, P; Jost, B; Neufeld, N

2003-01-01

The on-line data taking of the LHCb experiment at the future LHC collider will be controlled by a fully integrated and distributed Experiment Control System (ECS). The ECS will supervise both the detector operation (DCS) and the trigger and data acquisition (DAQ) activities of the experiment. These tasks require a large distributed information management system. The aim of this paper is to show how the control and monitoring of software processes such as trigger algorithms are integrated in the ECS of LHCb.

Quantitative reliability assessment for safety critical system software

International Nuclear Information System (INIS)

Chung, Dae Won; Kwon, Soon Man

2005-01-01

An essential issue in the replacement of the old analogue I and C to computer-based digital systems in nuclear power plants is the quantitative software reliability assessment. Software reliability models have been successfully applied to many industrial applications, but have the unfortunate drawback of requiring data from which one can formulate a model. Software which is developed for safety critical applications is frequently unable to produce such data for at least two reasons. First, the software is frequently one-of-a-kind, and second, it rarely fails. Safety critical software is normally expected to pass every unit test producing precious little failure data. The basic premise of the rare events approach is that well-tested software does not fail under normal routine and input signals, which means that failures must be triggered by unusual input data and computer states. The failure data found under the reasonable testing cases and testing time for these conditions should be considered for the quantitative reliability assessment. We will present the quantitative reliability assessment methodology of safety critical software for rare failure cases in this paper

Development of a parallel trigger framework for rare decay searches

CERN Document Server

Pantaleo, Felice

The simplicity of kaon decays (few decay channels, low final-state multiplicities) enable the possibility to reach an excellent sensitivity in the searches of lepton flavor violating decays. The experimental characteristics of decays like $K^+\\to \\pi^- \\mu^+ \\mu^+$ are very clear and allow an efficient background rejection. However, the measurement of this kind of events requires the production of a remarkable number of kaon decays. The bandwidth of tape recording system currently available does not allow the storage of all the produced events. A multi-stage selection of the potentially interesting events is required (trigger). At NA62, a first selection is done in real-time (response time $<1$ ms) by the level 0 trigger. The level 0 trigger is based on programmable logic (FPGA) that does not allow the same flexibility of the processors used for software programmable computers. The performance of parallel architectures like multi-cores CPUs and GPUs (Graphics Processing Units), located on computers grap...

Triggering and W-Polarisation Studies with CMS at the LHC

CERN Document Server

Marrouche, Jad

2010-01-01

Results from studies on the commissioning of the Global Calorimeter Trigger (GCT) of the CMS experiment are presented. Event-by-event comparisons of the hardware with a bit-level software emulation are used to achieve 100% agreement for all trigger quantities. In addition, a missing energy trigger based on jets is motivated using a simulation study, and consequently implemented and commissioned in the GCT. Furthermore, a templated-fit method for measuring the polarisation of W bosons at the LHC in the Helicity Frame is developed, and validated in simulation. An analysis of the first 3.2/pb of sqrt(s) = 7 TeV LHC data in the muon channel yields values of (fL − fR)+ = 0.347 ± 0.070, f0+ = 0.240 ± 0.176, and (fL − fR)− = 0.097 ± 0.088, f0− = 0.262 ± 0.196 for positive and negative charges respectively. The errors quoted are statistical. A preliminary systematic study is also presented.

Performance and robustness studies of the trigger for the ATLAS experiment

CERN Document Server

AUTHOR|(CDS)2068300; Teixeira-Dias, Pedro

2008-01-01

The ATLAS detector is one of two general-purpose particle detectors that will soon begin taking data at the Large Hadron Collider (LHC) at CERN. It is designed to explore a new energy frontier and answer fundamental questions about the nature of matter and the forces that shape the universe. The ATLAS trigger system is designed to select rare physics processes of interest from an extremely high rate of proton-proton collisions produced by the LHC. It is comprised of three levels. The first level is hardware-based. The second- and third-level triggers are software-based and are collectively known as the High-Level Trigger (HLT). The first part of this thesis is a study of the time overhead of the data navigation mechanism used by the HLT. The results of this study highlighted key areas for improvement within the design of the navigation mechanism. The second part of this thesis is a study of the impact of unresponsive electromagnetic calorimeter cells and Front-End Boards (FEBs) on electron trigger efficiencie...

Performance and development for the Inner Detector Trigger algorithms at ATLAS

CERN Document Server

Penc, O; The ATLAS collaboration

2014-01-01

The performance of the ATLAS Inner Detector (ID) Trigger algorithms being developed for running on the ATLAS High Level Trigger (HLT) processor farm during Run 2 of the LHC are presented. During the 2013-14 LHC long shutdown modifications are being carried out to the LHC accelerator to increase both the beam energy and luminosity. These modifications will pose significant challenges for the ID Trigger algorithms, both in terms execution time and physics performance. To meet these challenges, the ATLAS HLT software is being restructured to run as a more flexible single stage HLT, instead of two separate stages (Level2 and Event Filter) as in Run 1. This will reduce the overall data volume that needs to be requested by the HLT system, since data will no longer need to be requested for each of the two separate processing stages. Development of the ID Trigger algorithms for Run 2, currently expected to be ready for detector commissioning near the end of 2014, is progressing well and the current efforts towards op...

The Upgrade of the ATLAS $e/\\gamma$ Triggers for Run2 and their Performance

CERN Document Server

ATLAS Collaboration; The ATLAS collaboration

2016-01-01

Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for signal selection in a wide variety of ATLAS physics analyses to study Standard Model processes and to search for new phenomena. Final states including leptons and photons had, for example, an important role in the discovery and measurement of the Higgs particle. Dedicated triggers are also used to collect data for calibration, efficiency and fake rate measurements. The ATLAS trigger system is divided in a hardware-based (Level 1) and a software based high level trigger (HLT), both of which were upgraded during the long shutdown of the LHC in preparation for data taking at $\\sqrt{s} = $ 13TeV . The increasing luminosity and more challenging pile-up conditions as well as the planned higher center-of-mass energy demanded the optimisation of the trigger selections at each level, to control the rates and keep efficiencies high. To improve the performance multivariate analysis techniques are introduced at the HLT. ...

CDF tau triggers, analysis and other developments

International Nuclear Information System (INIS)

J. R. Smith

2003-01-01

This note is a write-up of contribution made by the author to the HCP2002 conference. It has two principal subjects. The first subject concerns the CDF τ triggers, τ-cone algorithms and τ physics analysis. τ physics is going to be very important in Run II because τ's can extend SUSY searches at large tan β in particular, τ's will help in the searches for (tilde χ) 1 ± (tilde χ) 2 0 , MSSM Higgs and other non Standard Model (SM) processes. Also, τ events are important for various Standard Model processes including Precision Electroweak, t(bar t), and SM Higgs searches. τ triggers are installed and operating at CDF. The second subject of this contribution to the HCP2002 conference concerns the algorithms of backwards differentiation abstracted from their usual setting inside of Automatic Differentiation software packages. Backwards differentiation (reverse-mode differentiation) provides a useful means for optimizing many kinds of problems

Generators, Calorimeter Trigger and J/ψ production at LHCb

CERN Document Server

Robbe, P

This document presents results related to the preparation of the physics program ofLHCb: generator software development, calorimeter trigger commissioning and measurement of J/psi production. A detailed simulation is mandatory to developthe analysis tools needed for this program and a detailed generator framework hasbeen implemented which describes for example B mixing and CP violation in B decays in the LHCb hadronic environment. For hadronic decay modes, the trigger of the experiment is based at the first level on information provided by the calorimeters, and in particular the hadronic calorimeter. The large J/psi production cross-section at the LHC allows to perform, with the first data recorded, a measurement of the J/psi differential cross-section and to confront it with theoretical models to test QCD in the heavy quark sector.

Tracking and flavour tagging selection in the ATLAS High Level Trigger

CERN Document Server

Calvetti, Milene; The ATLAS collaboration

2017-01-01

In high-energy physics experiments, track based selection in the online environment is crucial for the efficient real time selection of the rare physics process of interest. This is of particular importance at the Large Hadron Collider (LHC), where the increasingly harsh collision environment is challenging the experiments to improve the performance of their online selection. Principal among these challenges is the increasing number of interactions per bunch crossing, known as pileup. In the ATLAS experiment the challenge has been addressed with multiple strategies. Firstly, specific trigger objects have been improved by building algorithms using detailed tracking and vertexing in specific detector regions to improve background rejection without loosing signal efficiency. Secondly, since 2015 all trigger areas have benefited from a new high performance Inner Detector (ID) software tracking system implemented in the High Level Trigger. Finally, performance will be further enhanced in future by the installation...

D0 experiment: its trigger, data acquisition, and computers

International Nuclear Information System (INIS)

Cutts, D.; Zeller, R.; Schamberger, D.; Van Berg, R.

1984-05-01

The new collider facility to be built at Fermilab's Tevatron-I D0 region is described. The data acquisition requirements are discussed, as well as the hardware and software triggers designed to meet these needs. An array of MicroVAX computers running VAXELN will filter in parallel (a complete event in each microcomputer) and transmit accepted events via Ethernet to a host. This system, together with its subsequent offline needs, is briefly presented

The 40 MHz trigger-less DAQ for the LHCb Upgrade

Energy Technology Data Exchange (ETDEWEB)

Campora Perez, D.H. [INFN CNAF, Bologna (Italy); Falabella, A., E-mail: antonio.falabella@cnaf.infn.it [CERN, Geneva (Switzerland); Galli, D. [INFN Sezione di Bologna, Bologna (Italy); Università Bologna, Bologna (Italy); Giacomini, F. [CERN, Geneva (Switzerland); Gligorov, V. [INFN CNAF, Bologna (Italy); Manzali, M. [Università Bologna, Bologna (Italy); Università Ferrara, Ferrara (Italy); Marconi, U. [INFN Sezione di Bologna, Bologna (Italy); Neufeld, N.; Otto, A. [INFN CNAF, Bologna (Italy); Pisani, F. [INFN CNAF, Bologna (Italy); Università la Sapienza, Roma (Italy); Vagnoni, V.M. [INFN Sezione di Bologna, Bologna (Italy)

2016-07-11

The LHCb experiment will undergo a major upgrade during the second long shutdown (2018–2019), aiming to let LHCb collect an order of magnitude more data with respect to Run 1 and Run 2. The maximum readout rate of 1 MHz is the main limitation of the present LHCb trigger. The upgraded detector, apart from major detector upgrades, foresees a full read-out, running at the LHC bunch crossing frequency of 40 MHz, using an entirely software based trigger. A new high-throughput PCIe Generation 3 based read-out board, named PCIe40, has been designed for this purpose. The read-out board will allow an efficient and cost-effective implementation of the DAQ system by means of high-speed PC networks. The network-based DAQ system reads data fragments, performs the event building, and transports events to the High-Level Trigger at an estimated aggregate rate of about 32 Tbit/s. Different architecture for the DAQ can be implemented, such as push, pull and traffic shaping with barrel-shifter. Possible technology candidates for the foreseen event-builder under study are InfiniBand and Gigabit Ethernet. In order to define the best implementation of the event-builder we are performing tests of the event-builder on different platforms with different technologies. For testing we are using an event-builder evaluator, which consists of a flexible software implementation, to be used on small size test beds as well as on HPC scale facilities. The architecture of DAQ system and up to date performance results will be presented.

GPUs for real-time processing in HEP trigger systems (CHEP2013: 20. international conference on computing in high energy and nuclear physics)

Energy Technology Data Exchange (ETDEWEB)

Lamanna, G; Lamanna, G; Piandani, R [INFN, Pisa (Italy); Ammendola, R [INFN, Rome " Tor Vergata" (Italy); Bauce, M; Giagu, S; Messina, A [University, Rome " Sapienza" (Italy); Biagioni, A; Lonardo, A; Paolucci, P S; Rescigno, M; Simula, F; Vicini, P [INFN, Rome " Sapienza" (Italy); Fantechi, R [CERN, Geneve (Switzerland); Fiorini, M [University and INFN, Ferrara (Italy); Graverini, E; Pantaleo, F; Sozzi, M [University, Pisa (Italy)

2014-06-11

We describe a pilot project for the use of Graphics Processing Units (GPUs) for online triggering applications in High Energy Physics (HEP) experiments. Two major trends can be identified in the development of trigger and DAQ systems for HEP experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a pure software selection system (trigger-less). The very innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software both at low- and high-level trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerator in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming very attractive. We discuss in details the use of online parallel computing on GPUs for synchronous low-level trigger with fixed latency. In particular we show preliminary results on a first test in the NA62 experiment at CERN. The use of GPUs in high-level triggers is also considered, the ATLAS experiment (and in particular the muon trigger) at CERN will be taken as a study case of possible applications.

GPUs for real-time processing in HEP trigger systems (CHEP2013: 20. international conference on computing in high energy and nuclear physics)

International Nuclear Information System (INIS)

Lamanna, G; Lamanna, G; Piandani, R; Tor Vergata (Italy))" data-affiliation=" (INFN, Rome Tor Vergata (Italy))" >Ammendola, R; Sapienza (Italy))" data-affiliation=" (University, Rome Sapienza (Italy))" >Bauce, M; Sapienza (Italy))" data-affiliation=" (University, Rome Sapienza (Italy))" >Giagu, S; Sapienza (Italy))" data-affiliation=" (University, Rome Sapienza (Italy))" >Messina, A; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Biagioni, A; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Lonardo, A; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Paolucci, P S; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Rescigno, M; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Simula, F; Sapienza (Italy))" data-affiliation=" (INFN, Rome Sapienza (Italy))" >Vicini, P; Fantechi, R; Fiorini, M; Graverini, E; Pantaleo, F; Sozzi, M

2014-01-01

We describe a pilot project for the use of Graphics Processing Units (GPUs) for online triggering applications in High Energy Physics (HEP) experiments. Two major trends can be identified in the development of trigger and DAQ systems for HEP experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a pure software selection system (trigger-less). The very innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software both at low- and high-level trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerator in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming very attractive. We discuss in details the use of online parallel computing on GPUs for synchronous low-level trigger with fixed latency. In particular we show preliminary results on a first test in the NA62 experiment at CERN. The use of GPUs in high-level triggers is also considered, the ATLAS experiment (and in particular the muon trigger) at CERN will be taken as a study case of possible applications.

The evolution of the Trigger and Data Acquisition System in the ATLAS experiment

CERN Document Server

Krasznahorkay, A; The ATLAS collaboration

2014-01-01

The ATLAS experiment, aimed at recording the results of LHC proton-proton collisions, is upgrading its Trigger and Data Acquisition (TDAQ) system during the current LHC first long shutdown. The purpose of the upgrade is to add robustness and flexibility to the selection and the conveyance of the physics data, simplify the maintenance of the infrastructure, exploit new technologies and, overall, make ATLAS data-taking capable of dealing with increasing event rates. The TDAQ system used to date is organised in a three-level selection scheme, including a hardware-based first-level trigger and second- and third-level triggers implemented as separate software systems distributed on separate, commodity hardware nodes. While this architecture was successfully operated well beyond the original design goals, the accumulated experience stimulated interest to explore possible evolutions. We will also be upgrading the hardware of the TDAQ system by introducing new elements to it. For the high-level trigger, the current p...

Commissioning of the ATLAS high-level trigger with single beam and cosmic rays

CERN Document Server

Özcan, V Erkcan

2010-01-01

ATLAS is one of the two general-purpose detectors at the Large Hadron Collider (LHC). Using fast reconstruction algorithms, its trigger system needs to efficiently reject a huge rate of background events and still select potentially interesting ones with good efficiency. After a first processing level using custom electronics, the trigger selection is made by software running on two processor farms, designed to have 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 trigger. Following this period, ATLAS continued to collect cosmic-ray events for detector alignment and calibration purposes. These running periods allowed strict tests of the HLT reconstruction and selection algorithms as we...

Development of a level-1 trigger and timing system for the Double Chooz neutrino experiment

International Nuclear Information System (INIS)

Reinhold, Bernd

2009-01-01

components of the Level-1 Trigger and Timing System are introduced and described as well as their interfaces to other hard- and software components of the Double Chooz electronics and data acquisition system. Test procedures and software have been developed, which have been used to qualify the first prototypes of the Trigger Board and Trigger Master Board. In case of the Trigger Board this eventually led to the production of a second prototype with improved design. Especially the Analog Part of the Trigger Board, which is the most sensitive and critical section of the module, has been scrutinized and it could be demonstrated, that it meets the requirements of the Double Chooz Experiment. (orig.)

Development of a level-1 trigger and timing system for the Double Chooz neutrino experiment

Energy Technology Data Exchange (ETDEWEB)

Reinhold, Bernd

2009-02-25

this thesis all components of the Level-1 Trigger and Timing System are introduced and described as well as their interfaces to other hard- and software components of the Double Chooz electronics and data acquisition system. Test procedures and software have been developed, which have been used to qualify the first prototypes of the Trigger Board and Trigger Master Board. In case of the Trigger Board this eventually led to the production of a second prototype with improved design. Especially the Analog Part of the Trigger Board, which is the most sensitive and critical section of the module, has been scrutinized and it could be demonstrated, that it meets the requirements of the Double Chooz Experiment. (orig.)

TRIGGER

CERN Multimedia

J. Alimena

2013-01-01

Trigger Strategy Group The Strategy for Trigger Evolution And Monitoring (STEAM) group is responsible for the development of future High-Level Trigger menus, as well as of its DQM and validation, in collaboration and with the technical support of the PdmV group. Taking into account the beam energy and luminosity expected in 2015, a rough estimate of the trigger rates indicates a factor four increase with respect to 2012 conditions. Assuming that a factor two can be tolerated thanks to the increase in offline storage and processing capabilities, a toy menu has been developed using the new OpenHLT workflow to estimate the transverse energy/momentum thresholds that would halve the current trigger rates. The CPU time needed to run the HLT has been compared between data taken with 25 ns and 50 ns bunch spacing, for equivalent pile-up: no significant difference was observed on the global time per event distribution at the only available data point, corresponding to a pile-up of about 10 interactions. Using th...

Development of High Level Trigger Software for Belle II at SuperKEKB

International Nuclear Information System (INIS)

Lee, S; Itoh, R; Katayama, N; Mineo, S

2011-01-01

The Belle collaboration has been trying for 10 years to reveal the mystery of the current matter-dominated universe. However, much more statistics is required to search for New Physics through quantum loops in decays of B mesons. In order to increase the experimental sensitivity, the next generation B-factory, SuperKEKB, is planned. The design luminosity of SuperKEKB is 8 x 10 35 cm −2 s −1 a factor 40 above KEKB's peak luminosity. At this high luminosity, the level 1 trigger of the Belle II experiment will stream events of 300 kB size at a 30 kHz rate. To reduce the data flow to a manageable level, a high-level trigger (HLT) is needed, which will be implemented using the full offline reconstruction on a large scale PC farm. There, physics level event selection is performed, reducing the event rate by ∼ 10 to a few kHz. To execute the reconstruction the HLT uses the offline event processing framework basf2, which has parallel processing capabilities used for multi-core processing and PC clusters. The event data handling in the HLT is totally object oriented utilizing ROOT I/O with a new method of object passing over the UNIX socket connection. Also under consideration is the use of the HLT output as well to reduce the pixel detector event size by only saving hits associated with a track, resulting in an additional data reduction of ∼ 100 for the pixel detector. In this contribution, the design and implementation of the Belle II HLT are presented together with a report of preliminary testing results.

A 40 MHz Trigger-free Readout Architecture for the LHCb Experiment

CERN Document Server

Alessio, F; Guzik, Z

2009-01-01

The LHCb experiment is considering an upgrade towards a trigger-free 40 MHz complete event readout in which the event selection will only be performed on a processing farm by a high-level software trigger with access to all detector information. This would allow operating LHCb at ten times the current design luminosity and improving the trigger efficiencies in order to collect more than ten times the statistics foreseen in the first phase. In this paper we present the new architecture in consideration. In particular, we investigate new technologies and protocols for the distribution of timing and synchronous control commands, and rate control. This so called Timing and Fast Control (TFC) system will also perform a central destination control for the events and manage the load balancing of the readout network and the event filter farm. The TFC system will be centred on a single FPGA-based multimaster allowing concurrent stand-alone operation of any subset of sub-detectors. The TFC distribution network under in...

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...

CMS Software and Computing Ready for Run 2

CERN Document Server

Bloom, Kenneth

2015-01-01

In Run 1 of the Large Hadron Collider, software and computing was a strategic strength of the Compact Muon Solenoid experiment. The timely processing of data and simulation samples and the excellent performance of the reconstruction algorithms played an important role in the preparation of the full suite of searches used for the observation of the Higgs boson in 2012. In Run 2, the LHC will run at higher intensities and CMS will record data at a higher trigger rate. These new running conditions will provide new challenges for the software and computing systems. Over the two years of Long Shutdown 1, CMS has built upon the successes of Run 1 to improve the software and computing to meet these challenges. In this presentation we will describe the new features in software and computing that will once again put CMS in a position of physics leadership.

The ATLAS muon trigger performance in pp collisions at sqrt(s) = 8 TeV in year 2012 runs

CERN Document Server

Nobe, T; The ATLAS collaboration

2012-01-01

Events with muons in the final state are an important signature for many physics topics at Large Hadron Collider (LHC), for instance, searches for Higgs boson production or new phenomena, measurements on the standard model processes like top-quark, W, Z production. Thus, efficient trigger on muons in data taking and understanding its performance are crucial to perform these physics studies. At LHC high rejection power against large backgrounds, while maintaining high efficiency for rare signal events, is required for online selection at the trigger level. The ATLAS experiment employs a multi-level trigger architecture that selects the events in three sequential steps of increasing complexity and accuracy to cope with this challenging task. The L1 muon trigger system gets its input from fast muon trigger detectors. Fast sector logic boards select muon candidates, which are passed via an interface board to the central trigger processor and then to the High Level Trigger (HLT). The Muon HLT is purely software ba...

Contribution to the design and implementation of the trigger and acquisition system of the L3 experiment at LEP

International Nuclear Information System (INIS)

Cai, X.

1994-10-01

The thesis is devoted to the trigger and data acquisition system of the L3 experiment at LEP. It is a large distributed system with multiple levels to trigger, collect and record events detected by the L3 detector. The three trigger levels are designed to reduce a possible first level trigger rate of 100 Hz to a few Hz. The readout and event building systems have intermediate buffering so that the only dead time is only introduced during digitization of the detector signals. The emphasis of this thesis is on the Hadron Calorimeter (one of the sub detectors) readout system, the L3 event building system and the upgraded level-3-trigger system. Both hardware and software are described. (author). 126 refs., 48 figs., 23 tabs

Advanced Modular Software Performance Monitoring

CERN Multimedia

CERN. Geneva

2012-01-01

The LHCb software is based on the Gaudi framework, on top of which are built several large and complex software applications. The LHCb experiment is now in the active phase of collecting and analyzing data and significant performance problems arise in the Gaudi based software beginning from High Level Trigger (HLT) programs and ending with data analysis frameworks (DaVinci). It’s not easy to find hot spots in the code - only special tools can help to understand where CPU or memory usage is not reasonable. There exist many performance analyzing tools, but the main problem is that they show reports in terms of class and function names and such information usually is not very useful - the majority of algorithm developers use the Gaudi framework abstractions and usually do not know about functions which lie at the lower level. We will show a new approach which adds to performance reports a higher abstraction level based on knowledge of framework architecture and run-time object properties. A set of profiling to...

Advanced modular software performance monitoring

CERN Document Server

Mazurov, A

2012-01-01

The LHCb software is based on the Gaudi framework, on top of which are built several large and complex software applications. As the LHCb experiment is now in the active phase of collecting and analyzing data, performance problems arise in various parts of the software, from the High Level Trigger (HLT) programs to data analysis frameworks. It is not easy to find hotspots in the code - only specialized tools can help to understand where CPU or memory usage are not reasonable. There exist many performance analyzing tools, but the main problem is that they show reports in terms of class and function names and such information usually is not very useful - the majority of algorithm developers use the Gaudi framework abstractions and usually do not know about functions which lie at the lower level. We will show a new approach which adds to performance reports a higher abstraction level based on knowledge of framework architecture and run-time object properties. A set of profiling tools (based on Intel VTune Amplif...

First level trigger processor for the ZEUS calorimeter

International Nuclear Information System (INIS)

Dawson, J.W.; Talaga, R.L.; Burr, G.W.; Laird, R.J.; Smith, W.; Lackey, J.

1990-01-01

This paper discusses the design of the first level trigger processor for the ZEUS calorimeter. This processor accepts data from the 13,000 photomultipliers of the calorimeter which is topologically divided into 16 regions, and after regional preprocessing, performs logical and numerical operations which cross regional boundaries. Because the crossing period at the HERA collider is 96 ns, it is necessary that first-level trigger decisions be made in pipelined hardware. One microsecond is allowed for the processor to perform the required logical and numerical operations, during which time the data from ten crossings would be resident in the processor while being clocked through the pipelined hardware. The circuitry is implemented in 100K ECL, Advanced CMOS discrete devices, and programmable gate arrays, and operates in a VME environment. All tables and registers are written/read from VME, and all diagnostic codes are executed from VME. Preprocessed data flows into the processor at a rate of 5.2GB/s, and processed data flows from the processor to the Global First-Level Trigger at a rate of 700MB/s. The system allows for subsets of the logic to be configured by software and for various important variables to be histogrammed as they flow through the processor. 2 refs., 3 figs

First-level trigger processor for the ZEUS calorimeter

International Nuclear Information System (INIS)

Dawson, J.W.; Talaga, R.L.; Burr, G.W.; Laird, R.J.; Smith, W.; Lackey, J.

1990-01-01

The design of the first-level trigger processor for the Zeus calorimeter is discussed. This processor accepts data from the 13,000 photomultipliers of the calorimeter, which is topologically divided into 16 regions, and after regional preprocessing performs logical and numerical operations that cross regional boundaries. Because the crossing period at the HERA collider is 96 ns, it is necessary that first-level trigger decisions be made in pipelined hardware. One microsecond is allowed for the processor to perform the required logical and numerical operations, during which time the data from ten crossings would be resident in the processor while being clocked through the pipelined hardware. The circuitry is implemented in 100K emitter-coupled logic (ECL), advanced CMOS discrete devices and programmable gate arrays, and operates in a VME environment. All tables and registers are written/read from VME, and all diagnostic codes are executed from VME. Preprocessed data flows into the processor at a rate of 5.2 Gbyte/s, and processed data flows from the processor to the global first-level trigger at a rate of 70 Mbyte/s. The system allows for subsets of the logic to be configured by software and for various important variables to be histogrammed as they flow through the processor

Trigger Menu-aware Monitoring for the ATLAS experiment

CERN Document Server

Hoad, Xanthe; The ATLAS collaboration

2016-01-01

Changes in the trigger menu, the online algorithmic event-selection of the ATLAS experiment at the LHC in response to luminosity and detector changes are followed by adjustments in their monitoring system. This is done to ensure that the collected data is useful, and can be properly reconstructed at Tier-0, the first level of the computing grid. During Run 1, ATLAS deployed monitoring updates with the installation of new software releases at Tier-0. This created unnecessary overhead for developers and operators, and unavoidably led to different releases for the data-taking and the monitoring setup. We present a "trigger menu-aware" monitoring system designed for the ATLAS Run 2 data-taking. The new monitoring system aims to simplify the ATLAS operational workflows, and allows for easy and flexible monitoring configuration changes at the Tier-0 site via an Oracle DB interface. We present the design and the implementation of the menu-aware monitoring, along with lessons from the operational experience of the ne...

Flexible trigger menu implementation on the Global Trigger for the CMS Level-1 trigger upgrade

CERN Document Server

Matsushita, Takashi

2017-01-01

The CMS experiment at the Large Hadron Collider (LHC) has continued to explore physics at the high-energy frontier in 2016. The integrated luminosity delivered by the LHC in 2016 was 41~fb$^{-1}$ with a peak luminosity of 1.5 $\\times$ 10$^{34}$ cm$^{-2}$s$^{-1}$ and peak mean pile-up of about 50, all exceeding the initial estimations for 2016. The CMS experiment has upgraded its hardware-based Level-1 trigger system to maintain its performance for new physics searches and precision measurements at high luminosities. The Global Trigger is the final step of the CMS \\mbox{Level-1} trigger and implements a trigger menu, a set of selection requirements applied to the final list of objects from calorimeter and muon triggers, for reducing the 40 MHz collision rate to 100 kHz. The Global Trigger has been upgraded with state-of-the-art FPGA processors on Advanced Mezzanine Cards with optical links running at 10 GHz in a MicroTCA crate. The powerful processing resources of the upgraded system enable implemen...

Software upgradation of PXI based data acquisition for Aditya experiments

International Nuclear Information System (INIS)

Panchal, Vipul K.; Chavda, Chhaya; Patel, Vijay; Patel, Narendra; Ghosh, Joydeep

2015-01-01

Aditya Data Acquisition and Control System is designed to acquire data from diagnostics like Loop Voltage, Rogowski, Magnetic probes, X-rays etc and for control of gas feed, gate valve control, trigger pulse generation etc. CAMAC based data acquisition system was updated with PXI based Multifunction modules. The System is interfaced using optical connectivity with PC using PCI based controller module. Data is acquired using LabVIEW graphical user interface (GUI) and stored in server. The present GUI based application does not have features like module parameters configuration, analysis, webcasting etc. So a new application software using LabVIEW is being developed with features for individual module support considering programmable channel configuration - sampling rate, number of pre and post trigger samples, number of active channel selection etc. It would also have facility of using multi-functionality of timer and counter. The software would be scalable considering more modules, channels and crates along with security of different access level of user privileges. (author)

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...

GPUs for real-time processing in HEP trigger systems (ACAT2013: 15. international workshop on advanced computing and analysis techniques in physics research)

International Nuclear Information System (INIS)

Ammendola, R; Biagioni, A; Frezza, O; Cicero, F Lo; Lonardo, A; Messina, A; Paolucci, PS; Rossetti, D; Simula, F; Tosoratto, L; Vicini, P; Deri, L; Sozzi, M; Pantaleo, F; Fiorini, M; Lamanna, G

2014-01-01

We describe a pilot project (GAP – GPU Application Project) for the use of GPUs (Graphics processing units) for online triggering applications in High Energy Physics experiments. Two major trends can be identified in the development of trigger and DAQ systems for particle physics experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a fully software data selection system ( t rigger-less ) . The innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software not only in high level trigger levels but also in early trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerators in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high energy physics data acquisition and trigger systems is becoming relevant. We discuss in detail the use of online parallel computing on GPUs for synchronous low-level triggers with fixed latency. In particular we show preliminary results on a first test in the CERN NA62 experiment. The use of GPUs in high level triggers is also considered, the CERN ATLAS experiment being taken as a case study of possible applications

Use of Gaudi in the LVL2 Trigger: The Steering Controller

CERN Document Server

González, S; Wiedenmann, W

2002-01-01

A proposal is made for a thin interface layer between the Dataflow framework and the Level-2 event selection framework. After consideration of the Dataflow and the Level-2 Trigger requirements, we determine that both frameworks can be interfaced by means of a Finite State Machine, defining a clear boundary between the HLT data collection and the HLT event selection software. A prototype for this interface -- the Steering Controller -- is developed based on LHCb's Gaudi framework, which is also the basis for the ATLAS Event Filter and offline frameworks. The implications of choosing these "off-the-shelf" software components, both in terms of performance and architecture, are the subject of this note.

Experience with highly-parallel software for the storage system of the ATLAS Experiment at CERN

CERN Document Server

Colombo, T; The ATLAS collaboration

2012-01-01

The ATLAS experiment is observing proton-proton collisions delivered by the LHC accelerator. The ATLAS Trigger and Data Acquisition (TDAQ) system selects interesting events on-line in a three-level trigger system in order to store them at a budgeted rate of several hundred Hz. This paper focuses on the TDAQ data-logging system and in particular on the implementation and performance of a novel parallel software design. In this respect, the main challenge presented by the data-logging workload is the conflict between the largely parallel nature of the event processing, especially the recently introduced event compression, and the constraint of sequential file writing and checksum evaluation. This is further complicated by the necessity of operating in a fully data-driven mode, to cope with continuously evolving trigger and detector configurations. In this paper we report on the design of the new ATLAS on-line storage software. In particular we will discuss our development experience using recent concurrency-ori...

Prompt physics analysis from the trigger candidates at LHCb: strategy and new dedicated "TURBO" and PID calibration streams

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00038235

2016-01-01

During the first long shutdown of the LHC (2013-2014), the LHCb detector remained essentially unchanged, while the trigger system has been completely revised. Upgrades to the LHCb computing infrastructure have allowed for high quality decay information to be calculated by the software trigger, making separate offline event reconstruction unnecessary. The storage space of the triggered candidate is an order of magnitude smaller than the entire raw event that would otherwise need to be persisted. An application has been designed to process the information calculated by the trigger, with the resulting output used to directly perform physics measurements. Reaching the ultimate precision of the LHCb experiment in real time as the data arrive has the power to transform the experimental approach to processing large quantities of data.

The LHCb trigger

International Nuclear Information System (INIS)

Korolko, I.

1998-01-01

This paper describes progress in the development of the LHCb trigger system since the letter of intent. The trigger philosophy has significantly changed, resulting in an increase of trigger efficiency for signal B events. It is proposed to implement a level-1 vertex topology trigger in specialised hardware. (orig.)

Design Requirements, Epistemic Uncertainty and Solution Development Strategies in Software Design

DEFF Research Database (Denmark)

Ball, Linden J.; Onarheim, Balder; Christensen, Bo Thomas

2010-01-01

This paper investigates the potential involvement of “epistemic uncertainty” in mediating between complex design requirements and strategic switches in software design strategies. The analysis revealed that the designers produced an initial “first-pass” solution to the given design brief in a bre...... a view of software design as involving a mixed breadth-first and depth-first solution development approach, with strategic switching to depth-first design being triggered by requirement complexity and being mediated by associated feelings of uncertainty....

A Level-2 trigger algorithm for the identification of muons in the ATLAS Muon Spectrometer

CERN Document Server

Di Mattia, A; Dos Anjos, A; Baines, J T M; Bee, C P; Biglietti, M; Bogaerts, J A C; Boisvert, V; Bosman, M; Caron, B; Casado, M P; Cataldi, G; Cavalli, D; Cervetto, M; Comune, G; Conde-Muíño, P; De Santo, A; Díaz-Gómez, M; Dosil, M; Ellis, Nick; Emeliyanov, D; Epp, B; Falciano, S; Farilla, A; George, S; Ghete, V M; González, S; Grothe, M; Kabana, S; Khomich, A; Kilvington, G; Konstantinidis, N P; Kootz, A; Lowe, A; Luminari, L; Maeno, T; Masik, J; Meessen, C; Mello, A G; Merino, G; Moore, R; Morettini, P; Negri, A; Nikitin, N V; Nisati, A; Padilla, C; Panikashvili, N; Parodi, F; Pasqualucci, E; Pérez-Réale, V; Pinfold, J L; Pinto, P; Qian, Z; Resconi, S; Rosati, S; Sánchez, C; Santamarina-Rios, C; Scannicchio, D A; Schiavi, C; Segura, E; De Seixas, J M; Sivoklokov, S Yu; Soluk, R A; Stefanidis, E; Sushkov, S S; Sutton, M; Tapprogge, Stefan; Thomas, E; Touchard, F; Venda-Pinto, B; Vercesi, V; Werner, P; Wheeler, S; Wickens, F J; Wiedenmann, W; Wielers, M; Zobernig, G; Computing In High Energy Physics

2005-01-01

The ATLAS Level-2 trigger provides a software-based event selection after the initial Level-1 hardware trigger. For the muon events, the selection is decomposed in a number of broad steps: first, the Muon Spectrometer data are processed to give physics quantities associated to the muon track (standalone feature extraction) then, other detector data are used to refine the extracted features. The “µFast” algorithm performs the standalone feature extraction, providing a first reduction of the muon event rate from Level-1. It confirms muon track candidates with a precise measurement of the muon momentum. The algorithm is designed to be both conceptually simple and fast so as to be readily implemented in the demanding online environment in which the Level-2 selection code will run. Never-the-less its physics performance approaches, in some cases, that of the offline reconstruction algorithms. This paper describes the implemented algorithm together with the software techniques employed to increase its timing p...

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...

The ATLAS Trigger Core Configuration and Execution System in Light of the ATLAS Upgrade for LHC Run 2

CERN Document Server

Heinrich, Lukas; The ATLAS collaboration

2015-01-01

During the 2013/14 shutdown of the Large Hadron Collider (LHC) the ATLAS first level trigger (L1T) and the data acquisition system (DAQ) were substantially upgraded to cope with the increase in luminosity and collision multiplicity, expected to be delivered by the LHC in 2015. To name a few, the L1T was extended on the calorimeter side (L1Calo) to better cope with pile-up and apply better-tuned isolation criteria on electron, photon, and jet candidates. The central trigger (CT) was widened to analyze twice as many inputs, provide more trigger lines, and serve multiple sub-detectors in parallel during calibration periods. A new FPGA-based trigger, capable of analyzing event topologies at 40 MHz, was added to provide further input to forming the level 1 trigger decision (L1Topo). On the DAQ side the dataflow was completely remodeled, merging the two previously existing stages of the software-based high level trigger into one. Partially because of these changes, partially because of the new trigger paradigm to h...

The Resource utilization by ATLAS High Level Triggers. The contributed talk for the Technology and Instrumentation in Particle Physics 2011.

CERN Document Server

Ospanov, R; The ATLAS collaboration

2011-01-01

In 2010 the ATLAS experiment has 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 (L1) and software algorithms executing on commodity servers at the two higher levels: second level trigger (L2) and event filter (EF). The corresponding trigger rates are 75~kHz, 3~kHz and 200~Hz. The L2 uses custom algorithms to examine a small fraction of data at full detector granularity in Regions of Interest selected by the L1. The EF employs offline algorithms and full detector data for more computationally intensive analysis. The trigger selection is defined by trigger menus which consist of more than 500 individual trigger signatures, such as electrons, muons, particle jets, etc. An execution of a trigger signature incurs computing and data storage costs. A composition of the depl...

BAT Triggering Performance

Science.gov (United States)

McLean, Kassandra M.; Fenimore, E. E.; Palmer, D. M.; BAT Team

2006-09-01

The Burst Alert Telescope (BAT) onboard Swift has detected and located about 160 gamma-ray bursts (GRBs) in its first twenty months of operation. BAT employs two triggering systems to find GRBs: image triggering, which looks for a new point source in the field of view, and rate triggering, which looks for a significant increase in the observed counts. The image triggering system looks at 1 minute, 5 minute, and full pointing accumulations of counts in the detector plane in the energy range of 15-50 keV, with about 50 evaluations per pointing (about 40 minutes). The rate triggering system looks through 13 different time scales (from 4ms to 32s), 4 overlapping energy bins (covering 15-350 keV), 9 regions of the detector plane (from the full plane to individual quarters), and two background sampling models to search for GRBs. It evaluates 27000 trigger criteria in a second, for close to 1000 criteria. The image triggering system looks at 1, 5, and 40 minute accumulations of counts in the detector plane in the energy range of 15-50 keV. Both triggering systems are working very well with the settings from before launch and after we turned on BAT. However, we now have more than a year and a half of data to evaluate these triggering systems and tweak them for optimal performance, as well as lessons learned from these triggering systems.

Failures to be celebrated: an analysis of major pivots of software startups

OpenAIRE

Bajwa, Sohaib Shahid; Wang, Xiaofeng; Duc, Anh Nguyen; Abrahamsson, Pekka

2017-01-01

In the context of software startups, project failure is embraced actively and considered crucial to obtain validated learning that can lead to pivots. A pivot is the strategic change of a business concept, product or the different elements of a business model. A better understanding is needed on different types of pivots and different factors that lead to failures and trigger pivots, for software entrepreneurial teams to make better decisions under chaotic and unpredictable environment. Due t...

{Performance of the ATLAS Inner Detector Trigger algorithms in pp collisions at 7TeV

CERN Document Server

Masik, Jiri; The ATLAS collaboration

2011-01-01

The ATLAS trigger performs online event selection in three stages. The Inner Detector information is used in the second (Level 2) and third (Event Filter) stages. Track reconstruction in the silicon detectors and transition radiation tracker contributes significantly to the rejection of uninteresting events while retaining a high signal efficiency. To achieve an overall trigger execution time of 40 ms per event, Level 2 tracking uses fast custom algorithms. The Event Filter tracking uses modified offline algorithms, with an overall execution time of 4s per event. Performance of the trigger tracking algorithms with data collected by ATLAS in 2011 is shown. The high efficiency and track quality of the trigger tracking algorithms for identification of physics signatures is presented. We also discuss the robustness of the reconstruction software with respect to the presence of multiple interactions per bunch crossing, an increasingly important feature for optimal performance moving towards the design luminosities...

Performance of the ATLAS Inner Detector Trigger algorithms in pp collisions at 7TeV

CERN Document Server

Masik, Jiri; The ATLAS collaboration

2011-01-01

The ATLAS trigger performs online event selection in three stages. The Inner Detector information is used in the second (Level 2) and third (Event Filter) stages. Track reconstruction in the silicon detectors and transition radiation tracker contributes significantly to the rejection of uninteresting events while retaining a high signal efficiency. To achieve an overall trigger execution time of 40 ms per event, Level 2 tracking uses fast custom algorithms. The Event Filter tracking uses modified offline algorithms, with an overall execution time of 4s per event. Performance of the trigger tracking algorithms with data collected by ATLAS in 2011 is shown. The high efficiency and track quality of the trigger tracking algorithms for identification of physics signatures is presented. We also discuss the robustness of the reconstruction software with respect to the presence of multiple interactions per bunch crossing, an increasingly important feature for optimal performance moving towards the design luminosities...

A software framework for pipelined arithmetic algorithms in field programmable gate arrays

Science.gov (United States)

Kim, J. B.; Won, E.

2018-03-01

Pipelined algorithms implemented in field programmable gate arrays are extensively used for hardware triggers in the modern experimental high energy physics field and the complexity of such algorithms increases rapidly. For development of such hardware triggers, algorithms are developed in C++, ported to hardware description language for synthesizing firmware, and then ported back to C++ for simulating the firmware response down to the single bit level. We present a C++ software framework which automatically simulates and generates hardware description language code for pipelined arithmetic algorithms.

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.

TRIGGER

CERN Multimedia

W. Smith

Level-1 Trigger Hardware The CERN group is working on the TTC system. Seven out of nine sub-detector TTC VME crates with all fibers cabled are installed in USC55. 17 Local Trigger Controller (LTC) boards have been received from production and are in the process of being tested. The RF2TTC module replacing the TTCmi machine interface has been delivered and will replace the TTCci module used to mimic the LHC clock. 11 out of 12 crates housing the barrel ECAL off-detector electronics have been installed in USC55 after commissioning at the Electronics Integration Centre in building 904. The cabling to the Regional Calorimeter Trigger (RCT) is terminated. The Lisbon group has completed the Synchronization and Link mezzanine board (SLB) production. The Palaiseau group has fully tested and installed 33 out of 40 Trigger Concentrator Cards (TCC). The seven remaining boards are being remade. The barrel TCC boards have been tested at the H4 test beam, and good agreement with emulator predictions were found. The cons...

GPUs for real-time processing in HEP trigger systems (ACAT2013: 15. international workshop on advanced computing and analysis techniques in physics research)

Energy Technology Data Exchange (ETDEWEB)

Ammendola, R; Biagioni, A; Frezza, O; Cicero, F Lo; Lonardo, A; Messina, A; Paolucci, PS; Rossetti, D; Simula, F; Tosoratto, L; Vicini, P [INFN Roma,P.le A.Moro,2, 00185 Roma (Italy); Deri, L; Sozzi, M; Pantaleo, F [Pisa University, Largo B.Pontecorvo,3, 56127 Pisa (Italy); Fiorini, M [Ferrara University, Via Saragat,1, 44122 Ferrara (Italy); Lamanna, G [INFN Pisa, laro B.Pontecorvo,3, 56127 Pisa (Italy); Collaboration: GAP Collaboration

2014-06-06

We describe a pilot project (GAP – GPU Application Project) for the use of GPUs (Graphics processing units) for online triggering applications in High Energy Physics experiments. Two major trends can be identified in the development of trigger and DAQ systems for particle physics experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a fully software data selection system ({sup t}rigger-less{sup )}. The innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software not only in high level trigger levels but also in early trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerators in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high energy physics data acquisition and trigger systems is becoming relevant. We discuss in detail the use of online parallel computing on GPUs for synchronous low-level triggers with fixed latency. In particular we show preliminary results on a first test in the CERN NA62 experiment. The use of GPUs in high level triggers is also considered, the CERN ATLAS experiment being taken as a case study of possible applications.

Control software for the CBM readout chain

Energy Technology Data Exchange (ETDEWEB)

Loizeau, Pierre-Alain [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany)

2016-07-01

The Compressed Baryonic Matter (CBM) experiment, which will be built at FAIR, will use free-streaming readout electronics to acquire high-statistics data-sets of physics probes in fixed target heavy-ion collisions. Since no simple signatures suitable for a hardware trigger are available for most of them, reconstruction and selection of the interesting collisions will be done in software, in a computer farm called First Level Event Selector (FLES). The raw data coming from the detectors is pre-processed, pre-calibrated and aggregated in a FPGA based layer called Data Preprocessing Boards (DPB). IPbus will be used to communicate with the DPBs and through them with the elements of the readout chain closer to detectors. A slow control environment based on this software is developed by CBM to configure in an efficient way the DPBs as well as the Front-End Electronics and monitor their performances. This contribution presents the layout planned for the slow control software, its first implementation and corresponding test results.

Generic Software Architecture for Launchers

Science.gov (United States)

Carre, Emilien; Gast, Philippe; Hiron, Emmanuel; Leblanc, Alain; Lesens, David; Mescam, Emmanuelle; Moro, Pierre

2015-09-01

The definition and reuse of generic software architecture for launchers is not so usual for several reasons: the number of European launcher families is very small (Ariane 5 and Vega for these last decades); the real time constraints (reactivity and determinism needs) are very hard; low levels of versatility are required (implying often an ad hoc development of the launcher mission). In comparison, satellites are often built on a generic platform made up of reusable hardware building blocks (processors, star-trackers, gyroscopes, etc.) and reusable software building blocks (middleware, TM/TC, On Board Control Procedure, etc.). If some of these reasons are still valid (e.g. the limited number of development), the increase of the available CPU power makes today an approach based on a generic time triggered middleware (ensuring the full determinism of the system) and a centralised mission and vehicle management (offering more flexibility in the design and facilitating the long term maintenance) achievable. This paper presents an example of generic software architecture which could be envisaged for future launchers, based on the previously described principles and supported by model driven engineering and automatic code generation.

A Hardware Fast Tracker for the ATLAS Trigger: The Fast TracKer (FTK) Project.

CERN Document Server

Asbah, Nedaa; The ATLAS collaboration

2015-01-01

The trigger system of the ATLAS experiment is designed to reduce the event rate from the LHC nominal bunch crossing at 40 MHz to about 1 kHz, at the design luminosity of 10^{34} cm^{-2} s{-1}. After a successful period of data taking from 2010 to early 2013, the LHC is restarting in 2015 with much higher instantaneous luminosity and this will increase the load on High Level Trigger system, the second stage of the selection based on software algorithms. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals. The Fast TracKer is part of the ATLAS trigger upgrade project; it is a hardware processor that will provide, at every level-1 accept (100 kHz) and within 100 microseconds, full tracking information for tracks with momentum as low as 1 GeV. Providing fast extensive access to tracking information, with resolution comparable to the offline reconstruction, the Fast Tracker will for example help the High Level Trigger...

The Upgrade of the ATLAS Electron and Photon Triggers for LHC Run 2 and their Performance

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00220717; The ATLAS collaboration

2016-01-01

Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for signal selection in a wide variety of ATLAS physics analyses to study Standard Model processes and to search for new phenomena. Final states including leptons and photons had, for example, an important role in the discovery and measurement of the Higgs particle. Dedicated triggers are also used to collect data for calibration, efficiency and fake rate measurements. The ATLAS trigger system is divided in a hardware-based (Level 1) and a software based high level trigger (HLT), both of which were upgraded during the long shutdown of the LHC in preparation for data taking at $\\sqrt{s}$ = 13TeV. The increasing luminosity and more challenging pile-up conditions as well as the planned higher center-of-mass energy demanded the optimisation of the trigger selections at each level, to control the rates and keep efficiencies high. To improve the performance multivariate analysis techniques are introduced at the HLT. Th...

A Method to Select Software Test Cases in Consideration of Past Input Sequence

International Nuclear Information System (INIS)

Kim, Hee Eun; Kim, Bo Gyung; Kang, Hyun Gook

2015-01-01

In the Korea Nuclear I and C Systems (KNICS) project, the software for the fully-digitalized reactor protection system (RPS) was developed under a strict procedure. Even though the behavior of the software is deterministic, the randomness of input sequence produces probabilistic behavior of software. A software failure occurs when some inputs to the software occur and interact with the internal state of the digital system to trigger a fault that was introduced into the software during the software lifecycle. In this paper, the method to select test set for software failure probability estimation is suggested. This test set reflects past input sequence of software, which covers all possible cases. In this study, the method to select test cases for software failure probability quantification was suggested. To obtain profile of paired state variables, relationships of the variables need to be considered. The effect of input from human operator also have to be considered. As an example, test set of PZR-PR-Lo-Trip logic was examined. This method provides framework for selecting test cases of safety-critical software

Polymer as an alternative to Dojo for the Trigger Online Software

CERN Document Server

Dirkx, Glenn

2015-01-01

The human interfaces to Trigger Supervisor applications are built in the form of web applications, which is achieved with Dojo and C++ code. Dojo is a JavaScript library that allows users to define custom widgets (text boxes, buttons, sliders...), thereby extending basic HTML functionality. The following example creates a slider using nothing but a standard tag and JavaScript: This has been serving the project for quite some time, but some issues have been identified: •\tThe Dojo library is very outdated (v0.4, 9 years old) and no longer maintained: •\tthe risk of non-compatibility between the current TS GUIs and the browsers is very high, regardless whether they are used at the CMS control room or for development in general, •\tbrowsers are starting to put up deprecation notices for old Dojo code. Hence, TS GUIs are at risk of losing support for newer browsers as time passes. •\tCurrent C++ code is quite messy. Widgets can be defined, but the general layout of a page still needs to be generated in C++....

Software Defined Cyberinfrastructure

Energy Technology Data Exchange (ETDEWEB)

Foster, Ian; Blaiszik, Ben; Chard, Kyle; Chard, Ryan

2017-07-17

Within and across thousands of science labs, researchers and students struggle to manage data produced in experiments, simulations, and analyses. Largely manual research data lifecycle management processes mean that much time is wasted, research results are often irreproducible, and data sharing and reuse remain rare. In response, we propose a new approach to data lifecycle management in which researchers are empowered to define the actions to be performed at individual storage systems when data are created or modified: actions such as analysis, transformation, copying, and publication. We term this approach software-defined cyberinfrastructure because users can implement powerful data management policies by deploying rules to local storage systems, much as software-defined networking allows users to configure networks by deploying rules to switches.We argue that this approach can enable a new class of responsive distributed storage infrastructure that will accelerate research innovation by allowing any researcher to associate data workflows with data sources, whether local or remote, for such purposes as data ingest, characterization, indexing, and sharing. We report on early experiments with this approach in the context of experimental science, in which a simple if-trigger-then-action (IFTA) notation is used to define rules.

Large Scale Software Building with CMake in ATLAS

Science.gov (United States)

Elmsheuser, J.; Krasznahorkay, A.; Obreshkov, E.; Undrus, A.; ATLAS Collaboration

2017-10-01

The offline software of the ATLAS experiment at the Large Hadron Collider (LHC) serves as the platform for detector data reconstruction, simulation and analysis. It is also used in the detector’s trigger system to select LHC collision events during data taking. The ATLAS offline software consists of several million lines of C++ and Python code organized in a modular design of more than 2000 specialized packages. Because of different workflows, many stable numbered releases are in parallel production use. To accommodate specific workflow requests, software patches with modified libraries are distributed on top of existing software releases on a daily basis. The different ATLAS software applications also require a flexible build system that strongly supports unit and integration tests. Within the last year this build system was migrated to CMake. A CMake configuration has been developed that allows one to easily set up and build the above mentioned software packages. This also makes it possible to develop and test new and modified packages on top of existing releases. The system also allows one to detect and execute partial rebuilds of the release based on single package changes. The build system makes use of CPack for building RPM packages out of the software releases, and CTest for running unit and integration tests. We report on the migration and integration of the ATLAS software to CMake and show working examples of this large scale project in production.

Low Energy 8 B Solar Neutrinos with the Wideband Intelligent Trigger at Super-Kamiokande

Science.gov (United States)

Elnimr, Muhammad; Super-Kamiokande Collaboration

2017-09-01

The water Cherenkov experiment Super-Kamiokande (SK) has accumulated a sample of ˜ 90k solar neutrino data in the past two decades. Currently, the detector measures recoil electrons from solar 8 B neutrino-electron scattering above a kinetic energy of ˜ 3.5 MeV, limited by the capacity of the software trigger, although electrons as low as 2.5 MeV can be reconstructed. The next frontier for the low energy program at Super-K is the current operation of the Wideband Intelligent Trigger (WIT) to push the trigger threshold to the event reconstruction limit of 2.5 MeV. This opens up the possibility to explore the lower energy edge of the Mikheyev-Smirnov-Wolfenstein (MSW) effect in the sun. In this work we will present the prelimiary analysis of the accumlated WIT data taken so far as well as future prospects.

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

Triggering at high luminosity: fake triggers from pile-up

International Nuclear Information System (INIS)

Johnson, R.

1983-01-01

Triggers based on a cut in transverse momentum (p/sub t/) have proved to be useful in high energy physics both because they indicte that a hard constituent scattering has occurred and because they can be made quickly enough to gate electronics. These triggers will continue to be useful at high luminosities if overlapping events do not cause an excessive number of fake triggers. In this paper, I determine if this is indeed a problem at high luminosity machines

Software and Computing News

CERN Multimedia

Barberis, D

The last several months have been very busy ones for the ATLAS software developers. They've been trying to cope with the competing demands of multiple software stress tests and testbeds. These include Data Challenge Two (DC2), the Combined Testbeam (CTB), preparations for the Physics Workshop to be held in Rome in June 2005, and other testbeds, primarily one for the High-Level Trigger. Data Challenge 2 (DC2) The primary goal of this was to validate the computing model and to provide a test of simulating a day's worth of ATLAS data (10 million events) and of fully processing it and making it available to the physicists within 10 days (i.e. a 10% scale test). DC2 consists of three parts - the generation, simulation, and mixing of a representative sample of physics events with background events; the reconstruction of the mixed samples with initial classification into the different physics signatures; and the distribution of the data to multiple remote sites (Tier-1 centers) for analysis by physicists. Figu...

Trigger finger

Science.gov (United States)

... digit; Trigger finger release; Locked finger; Digital flexor tenosynovitis ... cut or hand Yellow or green drainage from the cut Hand pain or discomfort Fever If your trigger finger returns, call your surgeon. You may need another surgery.

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.

The charged particle trigger of the CELLO-detector

International Nuclear Information System (INIS)

Schroeder, V.

1981-01-01

The fast charged particle trigger of the CELLO-detector at the PETRA e + e - storage ring (DESY) is a fast software programmable hardware processor. It is using multiwire chamber signals as inputs and takes a decision on charged tracks coming from the interaction region in less than 1 μsec. The input signals are addressing Random Access Memory devices in which the mask schemes of all meaningful physical tracks are stored. The RAM output signals give information about the numbers and shapes of the valid masks found. This information is used for fast event acquisition and online data analysis done by a PDP 11 computer. (orig.)

Contribution to the elaboration and implementation of LEP-L3 second level microcoded Trigger

International Nuclear Information System (INIS)

Chollet, F.

1988-03-01

This thesis is devoted to the elaboration of the L3 second level trigger which is based on the dedicated programmable XOP processor. This system will reduce the trigger rate by a factor of ten and will ensure that the hardwired level-one processors function correctly. The present document describes all developments that L.A.P.P. is engaged in from the system design up to the complete experimental set up, especially: - The hardware development of the fast input memories as well as the FASTBUS interface unit which allows the microprocessor XOP to run as a performant FASTBUS Master, - the associated software developments, - the implementation of a VME test system dedicated to all control tasks [fr

The performance of the ATLAS Inner Detector Trigger algorithms in pp collisions at the LHC

International Nuclear Information System (INIS)

Sutton, Mark

2011-01-01

The ATLAS [The ATLAS Collaboration, The ATLAS Experiment at the CERN Large Hadron Collider, JINST 3:S08003, 2008 (2008)] Inner Detector trigger algorithms have been running online during data taking with proton-proton collisions at the Large Hadron Collider (LHC) since December 2009. Preliminary results on the performance of the algorithms in collisions at centre-of-mass energies of 900 GeV and 7 TeV, are discussed. The ATLAS trigger performs the online event selection in three stages. The Inner Detector information is used in the second and third triggering stages, referred to as Level-2 trigger (L2) and Event Filter (EF) respectively, or collectively as the High Level Trigger (HLT). The HLT runs software algorithms on large farms of commercial CPUs and is designed to reject collision events in real time, keeping the most interesting few events in every thousand. The average execution times per event at L2 and the EF are around 40 ms and 4 s respectively and the Inner Detector trigger algorithms can use only a fraction of these times. Within these times, data from interesting regions of the Inner Detector have to be read out through the network, unpacked, clustered and converted to the ATLAS global coordinates. The pattern recognition follows to identify the trajectories of charged particles (tracks), which are then used in combination with information from the other subdetectors to accept or reject events depending on whether they satisfy certain trigger signatures.

Real-time configuration changes of the ATLAS High Level Trigger

CERN Document Server

Winklmeier, F

2010-01-01

The ATLAS High Level Trigger (HLT) is a distributed real-time software system that performs the final online selection of events produced during proton-proton collisions at the Large Hadron Collider (LHC). It is designed as a two-stage trigger and event filter running on a farm of commodity PC hardware. Currently the system consists of about 850 processing nodes and will be extended incrementally following the expected increase in luminosity of the LHC to about 2000 nodes. The event selection within the HLT applications is carried out by specialized reconstruction algorithms. The selection can be controlled via properties that are stored in a central database and are retrieved at the startup of the HLT processes, which then usually run continuously for many hours. To be able to respond to changes in the LHC beam conditions, it is essential that the algorithms can be re-configured without disrupting data taking while ensuring a consistent and reproducible configuration across the entire HLT farm. The technique...

Topological Trigger Developments

CERN Multimedia

Likhomanenko, Tatiana

2015-01-01

The main b-physics trigger algorithm used by the LHCb experiment is the so-called topological trigger. The topological trigger selects vertices which are a) detached from the primary proton-proton collision and b) compatible with coming from the decay of a b-hadron. In the LHC Run 1, this trigger utilized a custom boosted decision tree algorithm, selected an almost 100% pure sample of b-hadrons with a typical efficiency of 60-70%, and its output was used in about 60% of LHCb papers. This talk presents studies carried out to optimize the topological trigger for LHC Run 2. In particular, we have carried out a detailed comparison of various machine learning classifier algorithms, e.g., AdaBoost, MatrixNet and uBoost. The topological trigger algorithm is designed to select all "interesting" decays of b-hadrons, but cannot be trained on every such decay. Studies have therefore been performed to determine how to optimize the performance of the classification algorithm on decays not used in the training. These inclu...

Lessons from (triggered) tremor

Science.gov (United States)

Gomberg, Joan

2010-01-01

I test a “clock-advance” model that implies triggered tremor is ambient tremor that occurs at a sped-up rate as a result of loading from passing seismic waves. This proposed model predicts that triggering probability is proportional to the product of the ambient tremor rate and a function describing the efficacy of the triggering wave to initiate a tremor event. Using data mostly from Cascadia, I have compared qualitatively a suite of teleseismic waves that did and did not trigger tremor with ambient tremor rates. Many of the observations are consistent with the model if the efficacy of the triggering wave depends on wave amplitude. One triggered tremor observation clearly violates the clock-advance model. The model prediction that larger triggering waves result in larger triggered tremor signals also appears inconsistent with the measurements. I conclude that the tremor source process is a more complex system than that described by the clock-advance model predictions tested. Results of this and previous studies also demonstrate that (1) conditions suitable for tremor generation exist in many tectonic environments, but, within each, only occur at particular spots whose locations change with time; (2) any fluid flow must be restricted to less than a meter; (3) the degree to which delayed failure and secondary triggering occurs is likely insignificant; and 4) both shear and dilatational deformations may trigger tremor. Triggered and ambient tremor rates correlate more strongly with stress than stressing rate, suggesting tremor sources result from time-dependent weakening processes rather than simple Coulomb failure.

Systematic Analysis of Dynamic Earthquake Triggering Using the EarthScope's USArray Data

Science.gov (United States)

Cerda, I.; Gonzalez-Huizar, H.; Velasco, A. A.; Kilb, D. L.; Pankow, K. L.

2011-12-01

Advances are continually made in our understanding of the physics governing earthquake triggering, yet many questions remain. Here, we investigate if there exists a minimum dynamic stress threshold (i.e., in amplitude, frequency or both) required to trigger remote earthquakes using data collected by >400 stations in EarthScope's USArray Transportable Array (USArray TA) network, supplemented by data from ~100 local seismic network stations when available. We also assess if remote triggering is enhanced if the orientation of the passing seismic waves aligns favorably with the local stress field and/or orientation of faults in the local triggered region. The uniform spacing of the USArray TA stations across the contiguous USA allows us to examine these types of characteristics of remote triggering within a variety of tectonic provinces, background seismicity rates, and within regions of both documented cases of triggered earthquakes and areas of no known triggered earthquakes. Our work focuses on assessing remote triggering capabilities of two teleseismic megatrust events (Japan M=9.0 2011 and Chile M=8.8 2010) and two large regional events (Baja California M=7.2 2010 and Wells Nevada M=6.0 2008). These events provide a range of seismic wave amplitudes and orientations across the footprint of the USArray TA stations. We use the Antelope software to develop an automated detection algorithm that computes the short-term (1 s) average (STA) to long-term (10 s) average (LTA) ratio, which we apply to 5 Hz high pass filtered data. Using a threshold ratio of 3.5 we apply this algorithm to data spanning ±5 hours from the mainshock's P-wave arrival time. We find that for each of our four mainshocks our algorithm nets, on average, hundreds of detections within the 10 hour time windows. Results suggest the orientation of the passing seismic waves can play a role in the high (or low) number of detections in select regions (e.g., western part of Texas), but in other regions there

The Central Trigger Processor (CTP)

CERN Multimedia

Franchini, Matteo

2016-01-01

The Central Trigger Processor (CTP) receives trigger information from the calorimeter and muon trigger processors, as well as from other sources of trigger. It makes the Level-1 decision (L1A) based on a trigger menu.

The Trigger Processor and Trigger Processor Algorithms for the ATLAS New Small Wheel Upgrade

CERN Document Server

Lazovich, Tomo; The ATLAS collaboration

2015-01-01

The ATLAS New Small Wheel (NSW) is an upgrade to the ATLAS muon endcap detectors that will be installed during the next long shutdown of the LHC. Comprising both MicroMegas (MMs) and small-strip Thin Gap Chambers (sTGCs), this system will drastically improve the performance of the muon system in a high cavern background environment. The NSW trigger, in particular, will significantly reduce the rate of fake triggers coming from track segments in the endcap not originating from the interaction point. We will present an overview of the trigger, the proposed sTGC and MM trigger algorithms, and the hardware implementation of the trigger. In particular, we will discuss both the heart of the trigger, an ATCA system with FPGA-based trigger processors (using the same hardware platform for both MM and sTGC triggers), as well as the full trigger electronics chain, including dedicated cards for transmission of data via GBT optical links. Finally, we will detail the challenges of ensuring that the trigger electronics can ...

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...

Terra Harvest software architecture

Science.gov (United States)

Humeniuk, Dave; Klawon, Kevin

2012-06-01

Under the Terra Harvest Program, the DIA has the objective of developing a universal Controller for the Unattended Ground Sensor (UGS) community. The mission is to define, implement, and thoroughly document an open architecture that universally supports UGS missions, integrating disparate systems, peripherals, etc. The Controller's inherent interoperability with numerous systems enables the integration of both legacy and future UGS System (UGSS) components, while the design's open architecture supports rapid third-party development to ensure operational readiness. The successful accomplishment of these objectives by the program's Phase 3b contractors is demonstrated via integration of the companies' respective plug-'n'-play contributions that include controllers, various peripherals, such as sensors, cameras, etc., and their associated software drivers. In order to independently validate the Terra Harvest architecture, L-3 Nova Engineering, along with its partner, the University of Dayton Research Institute, is developing the Terra Harvest Open Source Environment (THOSE), a Java Virtual Machine (JVM) running on an embedded Linux Operating System. The Use Cases on which the software is developed support the full range of UGS operational scenarios such as remote sensor triggering, image capture, and data exfiltration. The Team is additionally developing an ARM microprocessor-based evaluation platform that is both energy-efficient and operationally flexible. The paper describes the overall THOSE architecture, as well as the design decisions for some of the key software components. Development process for THOSE is discussed as well.

Stay away from asthma triggers

Science.gov (United States)

Asthma triggers - stay away from; Asthma triggers - avoiding; Reactive airway disease - triggers; Bronchial asthma - triggers ... clothes. They should leave the coat outside or away from your child. Ask people who work at ...

A dynamic system for ATLAS software installation on OSG grid sites

International Nuclear Information System (INIS)

Zhao, X; Maeno, T; Wenaus, T; Leuhring, F; Youssef, S; Brunelle, J; De Salvo, A; Thompson, A S

2010-01-01

A dynamic and reliable system for installing the ATLAS software releases on Grid sites is crucial to guarantee the timely and smooth start of ATLAS production and reduce its failure rate. In this paper, we discuss the issues encountered in the previous software installation system, and introduce the new approach, which is built upon the new development in the areas of the ATLAS workload management system (PanDA), and software package management system (pacman). It is also designed to integrate with the EGEE ATLAS software installation framework. In the new system, ATLAS software releases are packaged as pacball, a uniquely identifiable and reproducible self-installing data file. The distribution of pacballs to remote sites is managed by ATLAS data management system (DQ2) and PanDA server. The installation on remote sites is automatically triggered by the PanDA pilot jobs. The installation job payload connects to a central ATLAS software installation portal, making the information of installation status easily accessible across OSG and EGEE Grids. The issues encountered in running the new system in production, and our future plan for improvement, will also be discussed.

Performance and development for the Inner Detector Trigger Algorithms at ATLAS

CERN Document Server

Penc, Ondrej; The ATLAS collaboration

2015-01-01

A redesign of the tracking algorithms for the ATLAS trigger for Run 2 starting in spring 2015 is in progress. The ATLAS HLT software has been restructured to run as a more flexible single stage HLT, instead of two separate stages (Level 2 and Event Filter) as in Run 1. The new tracking strategy employed for Run 2 will use a Fast Track Finder (FTF) algorithm to seed subsequent Precision Tracking, and will result in improved track parameter resolution and faster execution times than achieved during Run 1. The performance of the new algorithms has been evaluated to identify those aspects where code optimisation would be most beneficial. The performance and timing of the algorithms for electron and muon reconstruction in the trigger are presented. The profiling infrastructure, constructed to provide prompt feedback from the optimisation, is described, including the methods used to monitor the relative performance improvements as the code evolves.

The Resource Manager the ATLAS Trigger and Data Acquisition System

CERN Document Server

Aleksandrov, Igor; The ATLAS collaboration; Lehmann Miotto, Giovanna; Soloviev, Igor

2016-01-01

The Resource Manager of the ATLAS Trigger and Data Acquisition system The Resource Manager is one of the core components of the Data Acquisition system of the ATLAS experiment at the LHC. The Resource Manager marshals the right for applications to access resources which may exist in multiple but limited copies, in order to avoid conflicts due to program faults or operator errors. The access to resources is managed in a manner similar to what a lock manager would do in other software systems. All the available resources and their association to software processes are described in the Data Acquisition configuration database. The Resource Manager is queried about the availability of resources every time an application needs to be started. The Resource Manager’s design is based on a client-server model, hence it consists of two components: the Resource Manager "server" application and the "client" shared library. The Resource Manager server implements all the needed functionalities, while the Resource Manager c...

Triggered creep as a possible mechanism for delayed dynamic triggering of tremor and earthquakes

Science.gov (United States)

Shelly, David R.; Peng, Zhigang; Hill, David P.; Aiken, Chastity

2011-01-01

The passage of radiating seismic waves generates transient stresses in the Earth's crust that can trigger slip on faults far away from the original earthquake source. The triggered fault slip is detectable in the form of earthquakes and seismic tremor. However, the significance of these triggered events remains controversial, in part because they often occur with some delay, long after the triggering stress has passed. Here we scrutinize the location and timing of tremor on the San Andreas fault between 2001 and 2010 in relation to distant earthquakes. We observe tremor on the San Andreas fault that is initiated by passing seismic waves, yet migrates along the fault at a much slower velocity than the radiating seismic waves. We suggest that the migrating tremor records triggered slow slip of the San Andreas fault as a propagating creep event. We find that the triggered tremor and fault creep can be initiated by distant earthquakes as small as magnitude 5.4 and can persist for several days after the seismic waves have passed. Our observations of prolonged tremor activity provide a clear example of the delayed dynamic triggering of seismic events. Fault creep has been shown to trigger earthquakes, and we therefore suggest that the dynamic triggering of prolonged fault creep could provide a mechanism for the delayed triggering of earthquakes. ?? 2011 Macmillan Publishers Limited. All rights reserved.

The NOvA software testing framework

International Nuclear Information System (INIS)

Tamsett, M; Group, C

2015-01-01

The NOvA experiment at Fermilab is a long-baseline neutrino experiment designed to study vε appearance in a vμ beam. NOvA has already produced more than one million Monte Carlo and detector generated files amounting to more than 1 PB in size. This data is divided between a number of parallel streams such as far and near detector beam spills, cosmic ray backgrounds, a number of data-driven triggers and over 20 different Monte Carlo configurations. Each of these data streams must be processed through the appropriate steps of the rapidly evolving, multi-tiered, interdependent NOvA software framework. In total there are greater than 12 individual software tiers, each of which performs a different function and can be configured differently depending on the input stream. In order to regularly test and validate that all of these software stages are working correctly NOvA has designed a powerful, modular testing framework that enables detailed validation and benchmarking to be performed in a fast, efficient and accessible way with minimal expert knowledge. The core of this system is a novel series of python modules which wrap, monitor and handle the underlying C++ software framework and then report the results to a slick front-end web-based interface. This interface utilises modern, cross-platform, visualisation libraries to render the test results in a meaningful way. They are fast and flexible, allowing for the easy addition of new tests and datasets. In total upwards of 14 individual streams are regularly tested amounting to over 70 individual software processes, producing over 25 GB of output files. The rigour enforced through this flexible testing framework enables NOvA to rapidly verify configurations, results and software and thus ensure that data is available for physics analysis in a timely and robust manner. (paper)

The ALICE Software Release Validation cluster

International Nuclear Information System (INIS)

Berzano, D; Krzewicki, M

2015-01-01

One of the most important steps of software lifecycle is Quality Assurance: this process comprehends both automatic tests and manual reviews, and all of them must pass successfully before the software is approved for production. Some tests, such as source code static analysis, are executed on a single dedicated service: in High Energy Physics, a full simulation and reconstruction chain on a distributed computing environment, backed with a sample “golden” dataset, is also necessary for the quality sign off. The ALICE experiment uses dedicated and virtualized computing infrastructures for the Release Validation in order not to taint the production environment (i.e. CVMFS and the Grid) with non-validated software and validation jobs: the ALICE Release Validation cluster is a disposable virtual cluster appliance based on CernVM and the Virtual Analysis Facility, capable of deploying on demand, and with a single command, a dedicated virtual HTCondor cluster with an automatically scalable number of virtual workers on any cloud supporting the standard EC2 interface. Input and output data are externally stored on EOS, and a dedicated CVMFS service is used to provide the software to be validated. We will show how the Release Validation Cluster deployment and disposal are completely transparent for the Release Manager, who simply triggers the validation from the ALICE build system's web interface. CernVM 3, based entirely on CVMFS, permits to boot any snapshot of the operating system in time: we will show how this allows us to certify each ALICE software release for an exact CernVM snapshot, addressing the problem of Long Term Data Preservation by ensuring a consistent environment for software execution and data reprocessing in the future. (paper)

Software Development and Testing Approach and Challenges in a distributed HEP Collaboration

CERN Document Server

Burckhart-Chromek, Doris

2007-01-01

In developing the ATLAS [1] Trigger and Data Acquisition (TDAQ) software, the team is applying the iterative waterfall model, evolutionary process management, formal software inspection, and lightweight review techniques. The long preparation phase, with a geographically widespread development team required that the standard techniques be adapted to this HEP environment. The testing process is receiving special attention. Unit tests and check targets in nightly project builds form the basis for the subsequent software project release testing. The integrated software is then being run on computing farms that give further opportunites for gaining experience, fault finding, and acquiring ideas for improvement. Dedicated tests on a farm of up to 1000 nodes address the large-scale aspect of the project. Integration test activities on the experimental site include the special purpose-built event readout hardware. Deployment in detector commissioning starts the countdown towards running the final ATLAS experiment. T...

The NA27 trigger

International Nuclear Information System (INIS)

Bizzarri, R.; Di Capua, E.; Falciano, S.; Iori, M.; Marel, G.; Piredda, G.; Zanello, L.; Haupt, L.; Hellman, S.; Holmgren, S.O.; Johansson, K.E.

1985-05-01

We have designed and implemented a minimum bias trigger together with a fiducial volume trigger for the experiment NA27, performed at the CERN SPS. A total of more than 3 million bubble chamber pictures have been taken with a triggered cross section smaller than 75% of the total inelastic cross section. Events containing charm particles were triggered with an efficiency of 98 +2 sub(-3)%. With the fiducial volume trigger, the probability for a picture to contain an interaction in the visible hydrogen increased from 47.3% to 59.5%, reducing film cost and processing effort with about 20%. The improvement in data taking rate is shown to be negligible. (author)

Performance of the L3 second level trigger implemented for the LEP II with the SGS Thomson C104 packet switch

International Nuclear Information System (INIS)

Blaising, J.J.; Chollet-Le Flour, F.; Cai, X.

1998-01-01

The L3 experiment is one of the four experiments collecting data at LEP. For the LEP phase 2, the second level trigger has been upgraded to a network of 28 ST T9000 transputers and 2 ST C104 asynchronous packet switches interconnected by IEEE1355 links. It collects trigger data at each LEP crossing (22 micros), builds-up the trigger data block, processes it and rejects online the background events in a few milliseconds. The L3 data acquisition has been running with this system since July 1995. In the data-taking environment and for different hardware and software implementations, the event building throughput rate has been measured. A bandwidth of 5.9 Mbytes per second per link has been measured in a configuration with 12 sources and one processing unit connected with 2 links. The expected global throughput of 70 Mbytes per second has been measured in a farm of 6 processing units. While varying the number of sources and destinations, the authors didn't observe any significant bandwidth loss. Nevertheless performance relies strongly on some software implementation choices, which are presented and discussed

Triggers of oral lichen planus flares and the potential role of trigger avoidance in disease management.

Science.gov (United States)

Chen, Hannah X; Blasiak, Rachel; Kim, Edwin; Padilla, Ricardo; Culton, Donna A

2017-09-01

Many patients with oral lichen planus (OLP) report triggers of flares, some of which overlap with triggers of other oral diseases, including oral allergy syndrome and oral contact dermatitis. The purpose of this study was to evaluate the prevalence of commonly reported triggers of OLP flares, their overlap with triggers of other oral diseases, and the potential role of trigger avoidance as a management strategy. Questionnaire-based survey of 51 patients with biopsy-proven lichen planus with oral involvement seen in an academic dermatology specialty clinic and/or oral pathology clinic between June 2014 and June 2015. Of the participants, 94% identified at least one trigger of their OLP flares. Approximately half of the participants (51%) reported at least one trigger that overlapped with known triggers of oral allergy syndrome, and 63% identified at least one trigger that overlapped with known triggers of oral contact dermatitis. Emotional stress was the most commonly reported trigger (77%). Regarding avoidance, 79% of the study participants reported avoiding their known triggers in daily life. Of those who actively avoided triggers, 89% reported an improvement in symptoms and 70% reported a decrease in the frequency of flares. Trigger identification and avoidance can play a potentially effective role in the management of OLP. Copyright © 2017 Elsevier Inc. All rights reserved.

Timing system control software in the SLC

International Nuclear Information System (INIS)

Thompson, K.; Phinney, N.

1985-04-01

A new timing system that allows precision (approx.1 to 2 ns) control of the trigger times of klystrons, beam position monitors, and other devices on a pulse-to-pulse basis at up to 360 Hz is in operation in the first third of the SLAC linear accelerator. The control software is divided between a central host VAX and local Intel 8086-based microprocessor clusters. Facilities exist to set up and adjust the timing of devices or groups of devices independently for beam pulses having different destinations and purposes, which are run in an interlaced fashion during normal machine operation. Upgrading of the system is currently underway, using a new version of the Programmable Delay Unit CAMAC module to allow pipelining of timing information for three machine pulses. An overview of the current state of the system is presented in this paper, with an emphasis on software control

How Open Source Has Changed the Software Industry: Perspectives from Open Source Entrepreneurs

Directory of Open Access Journals (Sweden)

Risto Rajala

2012-01-01

Full Text Available The emergence of F/LOSS (free/libre open source software has triggered several changes in the software industry. F/LOSS has been cited as an archetypal form of open innovation; it consists of the convergence and collaboration of like-minded parties. An increasing number of software firms have taken upon this approach to link outsiders into their service development and product design. Also, software firms have been increasingly grounded their business models on user-centric and service-oriented operations. This article describes a study that investigates these changes from the perspective of F/LOSS entrepreneurs. The findings are summarized into four issues that are critical in managing an F/LOSS business: i dealing with organizational changes in the innovation process; ii mastering user involvement; iii successfully using resources; and iv designing revenue models.

The processor farm for online triggering and full event reconstruction of the HERA-B experiment at HERA

International Nuclear Information System (INIS)

Gellrich, A.; Dippel, R.; Gensch, U.; Kowallik, R.; Legrand, I.C.; Leich, H.; Sun, F.; Wegner, P.

1996-01-01

The main goal of the HERA-B experiment which start taking data in 1988 is to study CP violation in B decays. This article describes the concept and the planned implementation of a multi-processor system, called processor farm,as the last part of the data acquisition and trigger system of the HERA B experiment. The third level trigger task and a full online event reconstruction will be performed on this processor farm, consisting of more then 100 powerful RISC processors which are based on commercial hardware boards. The controlling will be done by a real-time operating system which provides a software development environment, including FORTRAN and C compilers. (author)

Minimum Bias Trigger in ATLAS

International Nuclear Information System (INIS)

Kwee, Regina

2010-01-01

Since the restart of the LHC in November 2009, ATLAS has collected inelastic pp collisions to perform first measurements on charged particle densities. These measurements will help to constrain various models describing phenomenologically soft parton interactions. Understanding the trigger efficiencies for different event types are therefore crucial to minimize any possible bias in the event selection. ATLAS uses two main minimum bias triggers, featuring complementary detector components and trigger levels. While a hardware based first trigger level situated in the forward regions with 2.2 < |η| < 3.8 has been proven to select pp-collisions very efficiently, the Inner Detector based minimum bias trigger uses a random seed on filled bunches and central tracking detectors for the event selection. Both triggers were essential for the analysis of kinematic spectra of charged particles. Their performance and trigger efficiency measurements as well as studies on possible bias sources will be presented. We also highlight the advantage of these triggers for particle correlation analyses. (author)

Causality and headache triggers

Science.gov (United States)

Turner, Dana P.; Smitherman, Todd A.; Martin, Vincent T.; Penzien, Donald B.; Houle, Timothy T.

2013-01-01

Objective The objective of this study was to explore the conditions necessary to assign causal status to headache triggers. Background The term “headache trigger” is commonly used to label any stimulus that is assumed to cause headaches. However, the assumptions required for determining if a given stimulus in fact has a causal-type relationship in eliciting headaches have not been explicated. Methods A synthesis and application of Rubin’s Causal Model is applied to the context of headache causes. From this application the conditions necessary to infer that one event (trigger) causes another (headache) are outlined using basic assumptions and examples from relevant literature. Results Although many conditions must be satisfied for a causal attribution, three basic assumptions are identified for determining causality in headache triggers: 1) constancy of the sufferer; 2) constancy of the trigger effect; and 3) constancy of the trigger presentation. A valid evaluation of a potential trigger’s effect can only be undertaken once these three basic assumptions are satisfied during formal or informal studies of headache triggers. Conclusions Evaluating these assumptions is extremely difficult or infeasible in clinical practice, and satisfying them during natural experimentation is unlikely. Researchers, practitioners, and headache sufferers are encouraged to avoid natural experimentation to determine the causal effects of headache triggers. Instead, formal experimental designs or retrospective diary studies using advanced statistical modeling techniques provide the best approaches to satisfy the required assumptions and inform causal statements about headache triggers. PMID:23534872

A general-purpose trigger processor system and its application to fast vertex trigger

International Nuclear Information System (INIS)

Hazumi, M.; Banas, E.; Natkaniec, Z.; Ostrowicz, W.

1997-12-01

A general-purpose hardware trigger system has been developed. The system comprises programmable trigger processors and pattern generator/samplers. The hardware design of the system is described. An application as a prototype of the very fast vertex trigger in an asymmetric B-factory at KEK is also explained. (author)

BTeV Trigger

International Nuclear Information System (INIS)

Gottschalk, Erik E.

2006-01-01

BTeV was designed to conduct precision studies of CP violation in BB-bar events using a forward-geometry detector in a hadron collider. The detector was optimized for high-rate detection of beauty and charm particles produced in collisions between protons and antiprotons. The trigger was designed to take advantage of the main difference between events with beauty and charm particles and more typical hadronic events-the presence of detached beauty and charm decay vertices. The first stage of the BTeV trigger was to receive data from a pixel vertex detector, reconstruct tracks and vertices for every beam crossing, reject at least 98% of beam crossings in which neither beauty nor charm particles were produced, and trigger on beauty events with high efficiency. An overview of the trigger design and its evolution to include commodity networking and computing components is presented

Muon Event Filter Software for the ATLAS Experiment at LHC

CERN Document Server

Biglietti, M; Assamagan, Ketevi A; Baines, J T M; Bee, C P; Bellomo, M; Bogaerts, J A C; Boisvert, V; Bosman, M; Caron, B; Casado, M P; Cataldi, G; Cavalli, D; Cervetto, M; Comune, G; Conde, P; Conde-Muíño, P; De Santo, A; De Seixas, J M; Di Mattia, A; Dos Anjos, A; Dosil, M; Díaz-Gómez, M; Ellis, Nick; Emeliyanov, D; Epp, B; Falciano, S; Farilla, A; George, S; Ghete, V M; González, S; Grothe, M; Kabana, S; Khomich, A; Kilvington, G; Konstantinidis, N P; Kootz, A; Lowe, A; Luminari, L; Maeno, T; Masik, J; Meessen, C; Mello, A G; Merino, G; Moore, R; Morettini, P; Negri, A; Nikitin, N V; Nisati, A; Padilla, C; Panikashvili, N; Parodi, F; Pinfold, J L; Pinto, P; Primavera, M; Pérez-Réale, V; Qian, Z; Resconi, S; Rosati, S; Santamarina-Rios, C; Scannicchio, D A; Schiavi, C; Segura, E; Sivoklokov, S Yu; Soluk, R A; Stefanidis, E; Sushkov, S; Sutton, M; Sánchez, C; Tapprogge, Stefan; Thomas, E; Touchard, F; Venda-Pinto, B; Ventura, A; Vercesi, V; Werner, P; Wheeler, S; Wickens, F J; Wiedenmann, W; Wielers, M; Zobernig, G; Computing In High Energy Physics

2005-01-01

At LHC the 40 MHz bunch crossing rate dictates a high selectivity of the ATLAS Trigger system, which has to keep the full physics potential of the experiment in spite of a limited storage capability. The level-1 trigger, implemented in a custom hardware, will reduce the initial rate to 75 kHz and is followed by the software based level-2 and Event Filter, usually referred as High Level Triggers (HLT), which further reduce the rate to about 100 Hz. In this paper an overview of the implementation of the offline muon recostruction algortihms MOORE (Muon Object Oriented REconstruction) and MuId (Muon Identification) as Event Filter in the ATLAS online framework is given. The MOORE algorithm performs the reconstruction inside the Muon Spectrometer providing a precise measurement of the muon track parameters outside the calorimeters; MuId combines the measurements of all ATLAS sub-detectors in order to identify muons and provides the best estimate of their momentum at the production vertex. In the HLT implementatio...

Triggering trigeminal neuralgia

DEFF Research Database (Denmark)

Di Stefano, Giulia; Maarbjerg, Stine; Nurmikko, Turo

2018-01-01

Introduction Although it is widely accepted that facial pain paroxysms triggered by innocuous stimuli constitute a hallmark sign of trigeminal neuralgia, very few studies to date have systematically investigated the role of the triggers involved. In the recently published diagnostic classification...

LHCb Topological Trigger Reoptimization

CERN Document Server

INSPIRE-00400931; Ilten, Philip; Khairullin, Egor; Rogozhnikov, Alex; Ustyuzhanin, Andrey; Williams, Michael

2015-12-23

The main b-physics trigger algorithm used by the LHCb experiment is the so-called topological trigger. The topological trigger selects vertices which are a) detached from the primary proton-proton collision and b) compatible with coming from the decay of a b-hadron. In the LHC Run 1, this trigger, which utilized a custom boosted decision tree algorithm, selected a nearly 100% pure sample of b-hadrons with a typical efficiency of 60-70%; its output was used in about 60% of LHCb papers. This talk presents studies carried out to optimize the topological trigger for LHC Run 2. In particular, we have carried out a detailed comparison of various machine learning classifier algorithms, e.g., AdaBoost, MatrixNet and neural networks. The topological trigger algorithm is designed to select all "interesting" decays of b-hadrons, but cannot be trained on every such decay. Studies have therefore been performed to determine how to optimize the performance of the classification algorithm on decays not used in the training. ...

FELIX: a PCIe based high-throughput approach for interfacing front-end and trigger electronics in the ATLAS upgrade framework

CERN Document Server

Chen, Kai; The ATLAS collaboration

2016-01-01

The ATLAS Phase-I upgrade requires a Trigger and Data Acquisition (TDAQ) system able to trigger and record data from up to three times the nominal LHC instantaneous luminosity. The FELIX system provides this in a scalable, detector agnostic and easily upgradeable way. It is a PC-based gateway, routing between custom radiation tolerant optical links from front-end electronics, via FPGA PCIe Gen3 cards, and a commodity switched Ethernet or InfiniBand network. FELIX enables reducing custom electronics in favor of software on commercial servers. The FELIX system, results of demonstrator, design and testing of prototype are described.

g-PRIME: A Free, Windows Based Data Acquisition and Event Analysis Software Package for Physiology in Classrooms and Research Labs.

Science.gov (United States)

Lott, Gus K; Johnson, Bruce R; Bonow, Robert H; Land, Bruce R; Hoy, Ronald R

2009-01-01

We present g-PRIME, a software based tool for physiology data acquisition, analysis, and stimulus generation in education and research. This software was developed in an undergraduate neurophysiology course and strongly influenced by instructor and student feedback. g-PRIME is a free, stand-alone, windows application coded and "compiled" in Matlab (does not require a Matlab license). g-PRIME supports many data acquisition interfaces from the PC sound card to expensive high throughput calibrated equipment. The program is designed as a software oscilloscope with standard trigger modes, multi-channel visualization controls, and data logging features. Extensive analysis options allow real time and offline filtering of signals, multi-parameter threshold-and-window based event detection, and two-dimensional display of a variety of parameters including event time, energy density, maximum FFT frequency component, max/min amplitudes, and inter-event rate and intervals. The software also correlates detected events with another simultaneously acquired source (event triggered average) in real time or offline. g-PRIME supports parameter histogram production and a variety of elegant publication quality graphics outputs. A major goal of this software is to merge powerful engineering acquisition and analysis tools with a biological approach to studies of nervous system function.

The TOTEM modular trigger system

Energy Technology Data Exchange (ETDEWEB)

Bagliesi, M.G., E-mail: mg.bagliesi@pi.infn.i [University of Siena and INFN Pisa (Italy); Berretti, M.; Cecchi, R.; Greco, V.; Lami, S.; Latino, G.; Oliveri, E.; Pedreschi, E.; Scribano, A.; Spinella, F.; Turini, N. [University of Siena and INFN Pisa (Italy)

2010-05-21

The TOTEM experiment will measure the total cross-section with the luminosity independent method and study elastic and diffractive scattering at the LHC. We are developing a modular trigger system, based on programmable logic, that will select meaningful events within 2.5{mu}s. The trigger algorithm is based on a tree structure in order to obtain information compression. The trigger primitive is generated directly on the readout chip, VFAT, that has a specific fast output that gives low resolution hits information. In two of the TOTEM detectors, Roman Pots and T2, a coincidence chip will perform track recognition directly on the detector readout boards, while for T1 the hits are transferred from the VFATs to the trigger hardware. Starting from more than 2000 bits delivered by the detector electronics, we extract, in a first step, six trigger patterns of 32 LVDS signals each; we build, then, on a dedicated board, a 1-bit (L1) trigger signal for the TOTEM experiment and 16 trigger bits to the CMS experiment global trigger system for future common data taking.

The TOTEM modular trigger system

International Nuclear Information System (INIS)

Bagliesi, M.G.; Berretti, M.; Cecchi, R.; Greco, V.; Lami, S.; Latino, G.; Oliveri, E.; Pedreschi, E.; Scribano, A.; Spinella, F.; Turini, N.

2010-01-01

The TOTEM experiment will measure the total cross-section with the luminosity independent method and study elastic and diffractive scattering at the LHC. We are developing a modular trigger system, based on programmable logic, that will select meaningful events within 2.5μs. The trigger algorithm is based on a tree structure in order to obtain information compression. The trigger primitive is generated directly on the readout chip, VFAT, that has a specific fast output that gives low resolution hits information. In two of the TOTEM detectors, Roman Pots and T2, a coincidence chip will perform track recognition directly on the detector readout boards, while for T1 the hits are transferred from the VFATs to the trigger hardware. Starting from more than 2000 bits delivered by the detector electronics, we extract, in a first step, six trigger patterns of 32 LVDS signals each; we build, then, on a dedicated board, a 1-bit (L1) trigger signal for the TOTEM experiment and 16 trigger bits to the CMS experiment global trigger system for future common data taking.

LHCb Topological Trigger Reoptimization

International Nuclear Information System (INIS)

Likhomanenko, Tatiana; Khairullin, Egor; Rogozhnikov, Alex; Ustyuzhanin, Andrey; Ilten, Philip; Williams, Michael

2015-01-01

The main b-physics trigger algorithm used by the LHCb experiment is the so- called topological trigger. The topological trigger selects vertices which are a) detached from the primary proton-proton collision and b) compatible with coming from the decay of a b-hadron. In the LHC Run 1, this trigger, which utilized a custom boosted decision tree algorithm, selected a nearly 100% pure sample of b-hadrons with a typical efficiency of 60-70%; its output was used in about 60% of LHCb papers. This talk presents studies carried out to optimize the topological trigger for LHC Run 2. In particular, we have carried out a detailed comparison of various machine learning classifier algorithms, e.g., AdaBoost, MatrixNet and neural networks. The topological trigger algorithm is designed to select all ’interesting” decays of b-hadrons, but cannot be trained on every such decay. Studies have therefore been performed to determine how to optimize the performance of the classification algorithm on decays not used in the training. Methods studied include cascading, ensembling and blending techniques. Furthermore, novel boosting techniques have been implemented that will help reduce systematic uncertainties in Run 2 measurements. We demonstrate that the reoptimized topological trigger is expected to significantly improve on the Run 1 performance for a wide range of b-hadron decays. (paper)

Software in military aviation and drone mishaps: Analysis and recommendations for the investigation process

International Nuclear Information System (INIS)

Foreman, Veronica L.; Favaró, Francesca M.; Saleh, Joseph H.; Johnson, Christopher W.

2015-01-01

diversity of roles that software plays in military and civil aviation accidents. The identification of several specific mechanisms by which software contributes to accidents can help populate a library of patterns and triggers of software contributions to adverse events, a library which in turn can be used to help guide better software development, better coding, and better testing to avoid or eliminate these particular patterns and triggers. Finally, we strongly argue for the examination of software’s causal role in accident investigations, the inclusion of a section on the subject in the accident reports, and the participation of software experts in accident investigations. - Highlights: • Role of software in military aviation is investigated. • Shortcomings in the testing of particular avionic subsystems are identified. • Recommendations for improving the accident investigation process are provided

ATLAS Offline Software Performance Monitoring and Optimization

CERN Document Server

Chauhan, N; Kittelmann, T; Langenberg, R; Mandrysch , R; Salzburger, A; Seuster, R; Ritsch, E; Stewart, G; van Eldik, N; Vitillo, R

2014-01-01

In a complex multi-developer, multi-package software environment, such as the ATLAS offline Athena framework, tracking the performance of the code can be a non-trivial task in itself. In this paper we describe improvements in the instrumentation of ATLAS offline software that have given considerable insight into the performance of the code and helped to guide optimisation. Code can be instrumented firstly using the PAPI tool, which is a programing interface for accessing hardware performance counters. PAPI events can count floating point operations, cycles and instructions and cache accesses. Triggering PAPI to start/stop counting for each algorithm and processed event gives a good understanding of the whole algorithm level performance of ATLAS code. Further data can be obtained using pin, a dynamic binary instrumentation tool. Pintools can be used to obtain similar statistics as PAPI, but advantageously without requiring recompilation of the code. Fine grained routine and instruction level instrumentation is...

ATLAS Offline Software Performance Monitoring and Optimization

CERN Document Server

Chauhan, N; The ATLAS collaboration; Kittelmann, T; Langenberg, R; Mandrysch , R; Salzburger, A; Seuster, R; Ritsch, E; Stewart, G; van Eldik, N; Vitillo, R

2013-01-01

In a complex multi-developer, multi-package software environment, such as the ATLAS offline Athena framework, tracking the performance of the code can be a non-trivial task in itself. In this paper we describe improvements in the instrumentation of ATLAS offline software that have given considerable insight into the performance of the code and helped to guide optimisation. Code can be instrumented firstly using the PAPI tool, which is a programing interface for accessing hardware performance counters. PAPI events can count floating point operations, cycles and instructions and cache accesses. Triggering PAPI to start/stop counting for each algorithm and processed event gives a good understanding of the whole algorithm level performance of ATLAS code. Further data can be obtained using pin, a dynamic binary instrumentation tool. Pintools can be used to obtain similar statistics as PAPI, but advantageously without requiring recompilation of the code. Fine grained routine and instruction level instrumentation is...

The performance and development for the Inner Detector Trigger algorithms at ATLAS

International Nuclear Information System (INIS)

Penc, Ondrej

2015-01-01

A redesign of the tracking algorithms for the ATLAS trigger for LHC's Run 2 starting in 2015 is in progress. The ATLAS HLT software has been restructured to run as a more flexible single stage HLT, instead of two separate stages (Level 2 and Event Filter) as in Run 1. The new tracking strategy employed for Run 2 will use a Fast Track Finder (FTF) algorithm to seed subsequent Precision Tracking, and will result in improved track parameter resolution and faster execution times than achieved during Run 1. The performance of the new algorithms has been evaluated to identify those aspects where code optimisation would be most beneficial. The performance and timing of the algorithms for electron and muon reconstruction in the trigger are presented. The profiling infrastructure, constructed to provide prompt feedback from the optimisation, is described, including the methods used to monitor the relative performance improvements as the code evolves. (paper)

The performance and development for the Inner Detector Trigger algorithms at ATLAS

CERN Document Server

Penc, O; The ATLAS collaboration

2015-01-01

A redesign of the tracking algorithms for the ATLAS trigger for LHC's Run 2 starting in 2015 is in progress. The ATLAS HLT software has been restructured to run as a more flexible single stage HLT, instead of two separate stages (Level 2 and Event Filter) as in Run 1. The new tracking strategy employed for Run 2 will use a Fast Track Finder (FTF) algorithm to seed subsequent Precision Tracking, and will result in improved track parameter resolution and faster execution times than achieved during Run 1. The performance of the new algorithms has been evaluated to identify those aspects where code optimisation would be most beneficial. The performance and timing of the algorithms for electron and muon reconstruction in the trigger are presented. The profiling infrastructure, constructed to provide prompt feedback from the optimisation, is described, including the methods used to monitor the relative performance improvements as the code evolves.

Electrons and photons at High Level Trigger in CMS for Run II

CERN Document Server

Bin Anuar, Afiq Aizuddin

2015-01-01

The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increase in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. New approaches have been studied to keep the HLT output rate manageable while maintaining thresholds low enough to cover physics analyses. The strategy mainly relies on porting online the ingredients that have been successfully applied in the offline reconstruction, thus allowing to move HLT selection closer to offline cuts. Improvements in HLT electron and photon definitions will be presented, focusing in particular on updated clustering algorithm and the energy calibration procedure, new Particle-Flow-based isolation approach and pileup mitigation techniques, a...

Limited preemptive scheduling of mixed time-triggered and event-triggered tasks

NARCIS (Netherlands)

Heuvel, van den M.M.H.P.; Bril, R.J.; Zhang, X.; Abdullah, S.M.J.; Isovic, D.

2013-01-01

Many embedded systems have complex timing constraints and, at the same time, have flexibility requirements which prohibit offline planning of the entire system. To support a mixture of time-triggered and event-triggered tasks, some industrial systems deploy a table-driven dispatcher for

Tests of Event Filter Configuration Software

CERN Multimedia

Wickens, F.J.

TDAQ - Tests of Event Filter configuration software Within Trigger/DAQ a major consideration is how well the performance of the system components scale in going from the small set-ups used for development work to the final system with many hundreds of processors and links. In the case of the Event Filter, which makes the final stage of on-line event selection, plus on-line calibrations and monitoring, more than a thousand processors are envisaged. These processors will be divided into sub-farms, most will be remote from the detector and some could even be at institutes far from CERN. As part of the on-line system it is important that the software in the sub-farms can be reconfigured rapidly as runs start and stop, and that the system be fault tolerant. The flow of data inside a sub-farm involves many processes, for distribution and collection of results in addition to those for event processing itself. Supervision code written in Java has been developed to manage the processes within a cluster, with XML f...

Headache triggers in the US military.

Science.gov (United States)

Theeler, Brett J; Kenney, Kimbra; Prokhorenko, Olga A; Fideli, Ulgen S; Campbell, William; Erickson, Jay C

2010-05-01

Headaches can be triggered by a variety of factors. Military service members have a high prevalence of headache but the factors triggering headaches in military troops have not been identified. The objective of this study is to determine headache triggers in soldiers and military beneficiaries seeking specialty care for headaches. A total of 172 consecutive US Army soldiers and military dependents (civilians) evaluated at the headache clinics of 2 US Army Medical Centers completed a standardized questionnaire about their headache triggers. A total of 150 (87%) patients were active-duty military members and 22 (13%) patients were civilians. In total, 77% of subjects had migraine; 89% of patients reported at least one headache trigger with a mean of 8.3 triggers per patient. A wide variety of headache triggers was seen with the most common categories being environmental factors (74%), stress (67%), consumption-related factors (60%), and fatigue-related factors (57%). The types of headache triggers identified in active-duty service members were similar to those seen in civilians. Stress-related triggers were significantly more common in soldiers. There were no significant differences in trigger types between soldiers with and without a history of head trauma. Headaches in military service members are triggered mostly by the same factors as in civilians with stress being the most common trigger. Knowledge of headache triggers may be useful for developing strategies that reduce headache occurrence in the military.

The LHCb trigger

CERN Document Server

Hernando Morata, Jose Angel

2006-01-01

The LHCb experiment relies on an efficient trigger to select a rate up to 2 kHz of events useful for physics analysis from an initial rate of 10 MHz of visible collisions. In this contribution, we describe the different LHCb trigger algorithms and present their expected performance.

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

The trigger supervisor: Managing triggering conditions in a high energy physics experiment

International Nuclear Information System (INIS)

Wadsworth, B.; Lanza, R.; LeVine, M.J.; Scheetz, R.A.; Videbaek, F.

1987-01-01

A trigger supervisor, implemented in VME-bus hardware, is described, which enables the host computer to dynamically control and monitor the trigger configuration for acquiring data from multiple detector partitions in a complex experiment

Real time analysis with the upgraded LHCb trigger in Run-III

CERN Multimedia

Szumlak, Tomasz

2016-01-01

The current LHCb trigger system consists of a hardware level, which reduces the LHC bunch-crossing rate of 40 MHz to 1 MHz, a rate at which the entire detector is read out. A second level, implemented in a farm of around 20k parallel processing CPUs, the event rate is reduced to around 12.5 kHz. The LHCb experiment plans a major upgrade of the detector and DAQ system in the LHC long shutdown II (2018-2019 ). In this upgrade, a purely software based trigger system is being developed and it will have to process the full 30 MHz of bunch crossings with inelastic collisions. LHCb will also receive a factor of 5 increase in the instantaneous luminosity, which further contributes to the challenge of reconstructing and selecting events in real time with the CPU farm. We discuss the plans and progress towards achieving efficient reconstruction and selection with a 30 MHz throughput. Another challenge is to exploit the increased signal rate that results from removing the 1 MHz readout bottleneck, combined with the high...

Metronome LKM: An open source virtual keyboard driver to measure experiment software latencies.

Science.gov (United States)

Garaizar, Pablo; Vadillo, Miguel A

2017-10-01

Experiment software is often used to measure reaction times gathered with keyboards or other input devices. In previous studies, the accuracy and precision of time stamps has been assessed through several means: (a) generating accurate square wave signals from an external device connected to the parallel port of the computer running the experiment software, (b) triggering the typematic repeat feature of some keyboards to get an evenly separated series of keypress events, or (c) using a solenoid handled by a microcontroller to press the input device (keyboard, mouse button, touch screen) that will be used in the experimental setup. Despite the advantages of these approaches in some contexts, none of them can isolate the measurement error caused by the experiment software itself. Metronome LKM provides a virtual keyboard to assess an experiment's software. Using this open source driver, researchers can generate keypress events using high-resolution timers and compare the time stamps collected by the experiment software with those gathered by Metronome LKM (with nanosecond resolution). Our software is highly configurable (in terms of keys pressed, intervals, SysRq activation) and runs on 2.6-4.8 Linux kernels.

SOFTWARE OPEN SOURCE, SOFTWARE GRATIS?

Directory of Open Access Journals (Sweden)

Nur Aini Rakhmawati

2006-01-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Berlakunya Undang – undang Hak Atas Kekayaan Intelektual (HAKI, memunculkan suatu alternatif baru untuk menggunakan software open source. Penggunaan software open source menyebar seiring dengan isu global pada Information Communication Technology (ICT saat ini. Beberapa organisasi dan perusahaan mulai menjadikan software open source sebagai pertimbangan. Banyak konsep mengenai software open source ini. Mulai dari software yang gratis sampai software tidak berlisensi. Tidak sepenuhnya isu software open source benar, untuk itu perlu dikenalkan konsep software open source mulai dari sejarah, lisensi dan bagaimana cara memilih lisensi, serta pertimbangan dalam memilih software open source yang ada. Kata kunci :Lisensi, Open Source, HAKI

MANOLA - demonstration of the manipulator and transport vehicle system; MANOLA. Vorstellung des Manipulator- und Transportwagensystems

Energy Technology Data Exchange (ETDEWEB)

Kern, P.; Gentes, S. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Technologie und Management im Baubetrieb, Technologie und Management des Rueckbaus kerntechnischer Anlagen

2011-07-01

The deconstruction of nuclear facilities has triggered the construction of remote handling systems. For the decontamination of surfaces the use of automatic robotics has significantly decreased the dose rate of the personnel and increased the efficiency. The authors describe the carrier system for the project MANOLA (manipulator controlled laser ablation technology) that can not only move in vertical and horizontal direction but also circumnavigate obstacles. This has reduced the cycle time and increased the efficiency. The weight of the transport vehicle is also reduced compared to the previous system AMANDA.

Operational experience with the ALICE High Level Trigger

Science.gov (United States)

Szostak, Artur

2012-12-01

The ALICE HLT is a dedicated real-time system for online event reconstruction and triggering. Its main goal is to reduce the raw data volume read from the detectors by an order of magnitude, to fit within the available data acquisition bandwidth. This is accomplished by a combination of data compression and triggering. When HLT is enabled, data is recorded only for events selected by HLT. The combination of both approaches allows for flexible data reduction strategies. Event reconstruction places a high computational load on HLT. Thus, a large dedicated computing cluster is required, comprising 248 machines, all interconnected with InfiniBand. Running a large system like HLT in production mode proves to be a challenge. During the 2010 pp and Pb-Pb data-taking period, many problems were experienced that led to a sub-optimal operational efficiency. Lessons were learned and certain crucial changes were made to the architecture and software in preparation for the 2011 Pb-Pb run, in which HLT had a vital role performing data compression for ALICE's largest detector, the TPC. An overview of the status of the HLT and experience from the 2010/2011 production runs are presented. Emphasis is given to the overall performance, showing an improved efficiency and stability in 2011 compared to 2010, attributed to the significant improvements made to the system. Further opportunities for improvement are identified and discussed.

Operational experience with the ALICE High Level Trigger

International Nuclear Information System (INIS)

Szostak, Artur

2012-01-01

The ALICE HLT is a dedicated real-time system for online event reconstruction and triggering. Its main goal is to reduce the raw data volume read from the detectors by an order of magnitude, to fit within the available data acquisition bandwidth. This is accomplished by a combination of data compression and triggering. When HLT is enabled, data is recorded only for events selected by HLT. The combination of both approaches allows for flexible data reduction strategies. Event reconstruction places a high computational load on HLT. Thus, a large dedicated computing cluster is required, comprising 248 machines, all interconnected with InfiniBand. Running a large system like HLT in production mode proves to be a challenge. During the 2010 pp and Pb-Pb data-taking period, many problems were experienced that led to a sub-optimal operational efficiency. Lessons were learned and certain crucial changes were made to the architecture and software in preparation for the 2011 Pb-Pb run, in which HLT had a vital role performing data compression for ALICE's largest detector, the TPC. An overview of the status of the HLT and experience from the 2010/2011 production runs are presented. Emphasis is given to the overall performance, showing an improved efficiency and stability in 2011 compared to 2010, attributed to the significant improvements made to the system. Further opportunities for improvement are identified and discussed.

DUMAND data acquisition with triggering

International Nuclear Information System (INIS)

Brenner, A.E.; Theriot, D.; March, R.H.

1980-01-01

A data acquisition scheme for the standard DUMAND array that includes a simple triggering scheme as a fundamental part of the system is presented. Although there are a number of not yet fully understood parameters, it is assumed that thresholds can be set in such a manner as to give rise to a triggered signal that is not so dominated by randoms that it gives a substantial decrease in the data acquisition rate over that which would be required by a nontriggered system. It is also assumed that the triggering logic is relatively simple and does not need major computational capabilities for a trigger logic decision. With these assumptions, it is possible to generate the trigger at the array and restrict the data transfer to shore. However, with a not unreasonable delay of 200 microseconds, it is even possible to transmit the information for the trigger to shore and perform all that logic on the shore. The critical point is to send the minimum amount of information necessary to construct the trigger such that one need not send all the possible information in all detectors of the array continuously to shore. 1 figure

The ATLAS hadronic tau trigger

CERN Document Server

Black, C; The ATLAS collaboration

2012-01-01

With the high luminosities of proton-proton collisions achieved at the LHC, the strategies for triggering have become more important than ever for physics analysis. The naive inclusive single tau lepton triggers now suffer from severe rate limitations. To allow for a large program of physics analyses with taus, the development of topological triggers that combine tau signatures with other measured quantities in the event is required. These combined triggers open many opportunities to study new physics beyond the Standard Model and to search for the Standard Model Higgs. We present the status and performance of the hadronic tau trigger in ATLAS. We demonstrate that the ATLAS tau trigger ran remarkably well over 2011, and how the lessons learned from 2011 led to numerous improvements in the preparation of the 2012 run. These improvements include the introduction of tau selection criteria that are robust against varying pileup scenarios, and the implementation of multivariate selection techniques in the tau trig...

The ATLAS hadronic tau trigger

CERN Document Server

Black, C; The ATLAS collaboration

2012-01-01

With the high luminosities of proton-proton collisions achieved at the LHC, the strategies for triggering have become more important than ever for physics analysis. The naïve inclusive single tau lepton triggers now suffer from severe rate limitations. To allow for a large program of physics analyses with taus, the development of topological triggers that combine tau signatures with other measured quantities in the event is required. These combined triggers open many opportunities to study new physics beyond the Standard Model and to search for the Standard Model Higgs. We present the status and performance of the hadronic tau trigger in ATLAS. We demonstrate that the ATLAS tau trigger ran remarkably well over 2011, and how the lessons learned from 2011 led to numerous improvements in the preparation of the 2012 run. These improvements include the introduction of tau selection criteria that are robust against varying pileup scenarios, and the implementation of multivariate selection techniques in the tau tri...

Automatic Testing of the Trigger Data Serializer ASIC for the Upgrade of the ATLAS Muon Spectrometer

CERN Document Server

Pinkham, Reid; Schwarz, Thomas

The Trigger Data Serializer (TDS) is a custom designed Application Specific Integrated Circuit (ASIC) designed at the University of Michigan to be used on the ATLAS New Small Wheel (NSW) detector. The TDS is a central hub of the NSW trigger system. It prepares the trigger data for both pad and strip detectors, performs pad-strip matching, and serializes the matched strip data to other circuits on the rim of the NSW. In total, 6000 TDS chips will be produced. As part of the TDS’ initial production run, a test platform was developed to verify the functionality of each chip before being sent to users. The test platform consisted of multiple FPGA evaluation boards with custom designed mezzanine boards to hold the TDS chip during testing and control software running on a local computer. Of the initial run of 200 chips, 161 chips were tested with the automatic setup of which 158 passed. Detailed description of the TDS and automatic test fixture can be found in this thesis.

Searches for standard model Higgs boson and supersymmetry - Trigger studies and software tools development for new phenomena in the DO experiment

International Nuclear Information System (INIS)

Duperrin, A.

2007-04-01

This document presents a summary of my research work during the past 7 years for the preparation of the D0 experiment at Fermilab and the analysis of the data collected at the Tevatron hadron collider. It mainly focuses on 2 topics: trigger and direct search for new phenomena, particularly on supersymmetry and standard model Higgs boson searches. This document is divided into 5 chapters: 1) the phenomenology of the standard model and beyond, 2) the phenomenology of pp-bar events, 3) the Tevatron and D0 detector, 4) the trigger system and data acquisition, and 5) data analysis: search for supersymmetry and Higgs boson

Data analysis at the CMS level-1 trigger: migrating complex selection algorithms from offline analysis and high-level trigger to the trigger electronics

CERN Document Server

Wulz, Claudia

2017-01-01

With ever increasing luminosity at the LHC, optimum online data selection is becoming more and more important. While in the case of some experiments (LHCb and ALICE) this task is being completely transferred to computer farms, the others -- ATLAS and CMS -- will not be able to do this in the medium-term future for technological, detector-related reasons. Therefore, these experiments pursue the complementary approach of migrating more and more of the offline and high-level trigger intelligence into the trigger electronics. The presentation illustrates how the level-1 trigger of the CMS experiment and in particular its concluding stage, the so-called ``Global Trigger", take up this challenge.

Readout and trigger for the AFP detector at the ATLAS experiment at LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00097773; The ATLAS collaboration; Kocian, Martin; Lopez Paz, Ivan; Avoni, Giulio

2017-01-01

The ATLAS Forward Proton is a new detector system in ATLAS that allows study of events with protons scattered at very small angles. The final design assumes four stations at distances of 205 and 217 m from the ATLAS interaction point on both sides of the detector exploiting the Roman Pot technology. In 2016 two stations in one arm were installed; installation of the other two is planned for 2017. This article describes details of the installed hardware, firmware and software leading to the full integration with the ATLAS central trigger and data acquisition systems.

Nonlinear dynamical triggering of slow slip

Energy Technology Data Exchange (ETDEWEB)

Johnson, Paul A [Los Alamos National Laboratory; Knuth, Matthew W [WISCONSIN; Kaproth, Bryan M [PENN STATE; Carpenter, Brett [PENN STATE; Guyer, Robert A [Los Alamos National Laboratory; Le Bas, Pierre - Yves [Los Alamos National Laboratory; Daub, Eric G [Los Alamos National Laboratory; Marone, Chris [PENN STATE

2010-12-10

Among the most fascinating, recent discoveries in seismology have been the phenomena of triggered slip, including triggered earthquakes and triggered-tremor, as well as triggered slow, silent-slip during which no seismic energy is radiated. Because fault nucleation depths cannot be probed directly, the physical regimes in which these phenomena occur are poorly understood. Thus determining physical properties that control diverse types of triggered fault sliding and what frictional constitutive laws govern triggered faulting variability is challenging. We are characterizing the physical controls of triggered faulting with the goal of developing constitutive relations by conducting laboratory and numerical modeling experiments in sheared granular media at varying load conditions. In order to simulate granular fault zone gouge in the laboratory, glass beads are sheared in a double-direct configuration under constant normal stress, while subject to transient perturbation by acoustic waves. We find that triggered, slow, silent-slip occurs at very small confining loads ({approx}1-3 MPa) that are smaller than those where dynamic earthquake triggering takes place (4-7 MPa), and that triggered slow-slip is associated with bursts of LFE-like acoustic emission. Experimental evidence suggests that the nonlinear dynamical response of the gouge material induced by dynamic waves may be responsible for the triggered slip behavior: the slip-duration, stress-drop and along-strike slip displacement are proportional to the triggering wave amplitude. Further, we observe a shear-modulus decrease corresponding to dynamic-wave triggering relative to the shear modulus of stick-slips. Modulus decrease in response to dynamical wave amplitudes of roughly a microstrain and above is a hallmark of elastic nonlinear behavior. We believe that the dynamical waves increase the material non-affine elastic deformation during shearing, simultaneously leading to instability and slow-slip. The inferred

ATLAS: triggers for B-physics

International Nuclear Information System (INIS)

George, Simon

2000-01-01

The LHC will produce bb-bar events at an unprecedented rate. The number of events recorded by ATLAS will be limited by the rate at which they can be stored offline and subsequently analysed. Despite the huge number of events, the small branching ratios mean that analysis of many of the most interesting channels for CP violation and other measurements will be limited by statistics. The challenge for the Trigger and Data Acquisition (DAQ) system is therefore to maximise the fraction of interesting B decays in the B-physics data stream. The ATLAS Trigger/DAQ system is split into three levels. The initial B-physics selection is made in the first-level trigger by an inclusive low-p T muon trigger (∼6 GeV). The second-level trigger strategy is based on identifying classes of final states by their partial reconstruction. The muon trigger is confirmed before proceeding to a track search. Electron/hadron separation is given by the transition radiation tracking detector and the Electromagnetic calorimeter. Muon identification is possible using the muon detectors and the hadronic calorimeter. From silicon strips, pixels and straw tracking, precise track reconstruction is used to make selections based on invariant mass, momentum and impact parameter. The ATLAS trigger group is currently engaged in algorithm development and performance optimisation for the B-physics trigger. This is closely coupled to the R and D programme for the higher-level triggers. Together the two programmes of work will optimise the hardware, architecture and algorithms to meet the challenging requirements. This paper describes the current status and progress of this work

A flexible and reusable software for real-time control applications at JET

International Nuclear Information System (INIS)

De Tommasi, G.; Piccolo, F.; Sartori, F.

2005-01-01

The fast growth of the JET real-time control network and the increasing demand for new systems have been the triggers that started the development of the JETRT software framework. This new architecture is designed for maximum reuse and is particularly suited for implementation of both real-time control and data acquisition systems in a complex experimental environment such as JET. Most of the software is the same in all applications independent of the platform. The varying part is the project specific algorithm, which is also compiled into a separate software component, in order to achieve a separation from the plant interface code. This design choice maximises the software reliability, reduces development costs and allows non-specialist programmers to contribute to the implementation of real-time projects. JETRT also provides an integrated set of debugging and testing tools, some of them well integrated with the Matlab environment. This feature besides the framework portability among different platforms allows to perform most of the test and validation phase on a desktop PC running Windows, significantly reducing the commissioning time of a new real-time system

Designing signal-enriched triggers for boosted jets.

CERN Document Server

Toumazou, Marina

2017-01-01

Triggers designed to favour the selection of hadronically decaying massive particles have been studied. Both triggers using solely ET and mass cuts (similar to new 2017 triggers) and triggers exploiting polarization information have been studied. The mass cut triggers show substantial gains in rate reduction, while the benefits of polarization triggers are less obvious. The final conclusion is that it is more useful to identify and trigger on generic boosted decays, irrespective of the polarization of the decaying particle

CMS software and computing for LHC Run 2

CERN Document Server

INSPIRE-00067576

2016-11-09

The CMS offline software and computing system has successfully met the challenge of LHC Run 2. In this presentation, we will discuss how the entire system was improved in anticipation of increased trigger output rate, increased rate of pileup interactions and the evolution of computing technology. The primary goals behind these changes was to increase the flexibility of computing facilities where ever possible, as to increase our operational efficiency, and to decrease the computing resources needed to accomplish the primary offline computing workflows. These changes have resulted in a new approach to distributed computing in CMS for Run 2 and for the future as the LHC luminosity should continue to increase. We will discuss changes and plans to our data federation, which was one of the key changes towards a more flexible computing model for Run 2. Our software framework and algorithms also underwent significant changes. We will summarize the our experience with a new multi-threaded framework as deployed on ou...

NOvA Event Building, Buffering and Data-Driven Triggering From Within the DAQ System

International Nuclear Information System (INIS)

Fischler, M; Rechenmacher, R; Green, C; Kowalkowski, J; Norman, A; Paterno, M

2012-01-01

The NOvA experiment is a long baseline neutrino experiment design to make precision probes of the structure of neutrino mixing. The experiment features a unique deadtimeless data acquisition system that is capable acquiring and building an event data stream from the continuous readout of the more than 360,000 far detector channels. In order to achieve its physics goals the experiment must be able to buffer, correlate and extract the data in this stream with the beam-spills that occur that Fermilab. In addition the NOvA experiment seeks to enhance its data collection efficiencies for rare class of event topologies that are valuable for calibration through the use of data driven triggering. The NOvA-DDT is a prototype Data-Driven Triggering system. NOvA-DDT has been developed using the Fermilab artdaq generic DAQ/Event-building toolkit. This toolkit provides the advantages of sharing online software infrastructure with other Intensity Frontier experiments, and of being able to use any offline analysis module-unchanged-as a component of the online triggering decisions. We have measured the performance and overhead of NOvA-DDT framework using a Hough transform based trigger decision module developed for the NOvA detector to identify cosmic rays. The results of these tests which were run on the NOvA prototype near detector, yielded a mean processing time of 98 ms per event, while consuming only 1/16th of the available processing capacity. These results provide a proof of concept that a NOvA-DDT based processing system is a viable strategy for data acquisition and triggering for the NOvA far detector.

Towards RTOS support for mixed time-triggered and event-triggered task sets

NARCIS (Netherlands)

Heuvel, van den M.M.H.P.; Bril, R.J.; Lukkien, J.J.; Isovic, D.; Sankar Ramachandran, G.

2012-01-01

Many embedded systems have complex timing constraints and, at the same time, have flexibility requirements which prohibit offline planning of the entire system. To support a mixture of time-triggered and event-triggered tasks, some industrial systems deploy a real-time operating system (RTOS) with a

Optimisation of the ATLAS Track Reconstruction Software for Run-2

CERN Document Server

Salzburger, Andreas; The ATLAS collaboration

2015-01-01

Track reconstruction is one of the most complex element of the reconstruction of events recorded by ATLAS from collisions delivered by the LHC. It is the most time consuming reconstruction component in high luminosity environments. The flat budget projections for computing resources for Run-2 of the LHC together with the demands of reconstructing higher pile-up collision data at rates more than double those in Run-1 (an increase from 400 Hz to 1 kHz in trigger output) have put stringent requirements on the track reconstruction software. The ATLAS experiment has performed a two year long software campaign which aimed to reduce the reconstruction rate by a factor of three to meet the resource limitations for Run-2: the majority of the changes to achieve this were improvements to the track reconstruction software. The CPU processing time of ATLAS track reconstruction was reduced by more than a factor of three during this campaign without any loss of output information of the track reconstruction. We present the ...

The LVL2 trigger goes online

CERN Multimedia

David Berge

On Friday, the 9th of February, the ATLAS TDAQ community reached an important milestone. In a successful integration test, cosmic-ray muons were recorded with parts of the muon spectrometer, the central-trigger system and a second-level trigger algorithm. This was actually the first time that a full trigger slice all the way from the first-level trigger muon chambers up to event building after event selection by the second-level trigger ran online with cosmic rays. The ATLAS trigger and data acquisition system has a three-tier structure that is designed to cope with the enormous demands of proton-proton collisions at a bunch-crossing frequency of 40 MHz, with a typical event size of 1-2 MB. The online event selection has to reduce the incoming rate by a factor of roughly 200,000 to 200 Hz, a rate digestible by the archival-storage and offline-processing facilities. ATLAS has a mixed system: the first-level trigger (LVL1) is in hardware, while the other two consecutive levels, the second-level trigger (LVL2)...

The Database Driven ATLAS Trigger Configuration System

CERN Document Server

Martyniuk, Alex; The ATLAS collaboration

2015-01-01

This contribution describes the trigger selection configuration system of the ATLAS low- and high-level trigger (HLT) and the upgrades it received in preparation for LHC Run 2. The ATLAS trigger configuration system is responsible for applying the physics selection parameters for the online data taking at both trigger levels and the proper connection of the trigger lines across those levels. Here the low-level trigger consists of the already existing central trigger (CT) and the new Level-1 Topological trigger (L1Topo), which has been added for Run 2. In detail the tasks of the configuration system during the online data taking are Application of the selection criteria, e.g. energy cuts, minimum multiplicities, trigger object correlation, at the three trigger components L1Topo, CT, and HLT On-the-fly, e.g. rate-dependent, generation and application of prescale factors to the CT and HLT to adjust the trigger rates to the data taking conditions, such as falling luminosity or rate spikes in the detector readout ...

Automated load balancing in the ATLAS high-performance storage software

CERN Document Server

Le Goff, Fabrice; The ATLAS collaboration

2017-01-01

The ATLAS experiment collects proton-proton collision events delivered by the LHC accelerator at CERN. The ATLAS Trigger and Data Acquisition (TDAQ) system selects, transports and eventually records event data from the detector at several gigabytes per second. The data are recorded on transient storage before being delivered to permanent storage. The transient storage consists of high-performance direct-attached storage servers accounting for about 500 hard drives. The transient storage operates dedicated software in the form of a distributed multi-threaded application. The workload includes both CPU-demanding and IO-oriented tasks. This paper presents the original application threading model for this particular workload, discussing the load-sharing strategy among the available CPU cores. The limitations of this strategy were reached in 2016 due to changes in the trigger configuration involving a new data distribution pattern. We then describe a novel data-driven load-sharing strategy, designed to automatical...

DT Local Trigger performance in 2015

CERN Document Server

CMS Collaboration

2015-01-01

The Local Trigger system of the CMS Drift Tube chambers (DT) was checked applying similar methods as in the LHC Run 1 (2012). The main variables shown in this note are the trigger efficiency, the trigger quality and the fraction of trigger ghosts. The performance was found to be comparable or better than in Run 1.

Remotely Triggered Earthquakes Recorded by EarthScope's Transportable Array and Regional Seismic Networks: A Case Study Of Four Large Earthquakes

Science.gov (United States)

Velasco, A. A.; Cerda, I.; Linville, L.; Kilb, D. L.; Pankow, K. L.

2013-05-01

Changes in field stress required to trigger earthquakes have been classified in two basic ways: static and dynamic triggering. Static triggering occurs when an earthquake that releases accumulated strain along a fault stress loads a nearby fault. Dynamic triggering occurs when an earthquake is induced by the passing of seismic waves from a large mainshock located at least two or more fault lengths from the epicenter of the main shock. We investigate details of dynamic triggering using data collected from EarthScope's USArray and regional seismic networks located in the United States. Triggered events are identified using an optimized automated detector based on the ratio of short term to long term average (Antelope software). Following the automated processing, the flagged waveforms are individually analyzed, in both the time and frequency domains, to determine if the increased detection rates correspond to local earthquakes (i.e., potentially remotely triggered aftershocks). Here, we show results using this automated schema applied to data from four large, but characteristically different, earthquakes -- Chile (Mw 8.8 2010), Tokoku-Oki (Mw 9.0 2011), Baja California (Mw 7.2 2010) and Wells Nevada (Mw 6.0 2008). For each of our four mainshocks, the number of detections within the 10 hour time windows span a large range (1 to over 200) and statistically >20% of the waveforms show evidence of anomalous signals following the mainshock. The results will help provide for a better understanding of the physical mechanisms involved in dynamic earthquake triggering and will help identify zones in the continental U.S. that may be more susceptible to dynamic earthquake triggering.

FELIX: a PCIe based high-throughput approach for interfacing front-end and trigger electronics in the ATLAS Upgrade framework

Science.gov (United States)

Anderson, J.; Bauer, K.; Borga, A.; Boterenbrood, H.; Chen, H.; Chen, K.; Drake, G.; Dönszelmann, M.; Francis, D.; Guest, D.; Gorini, B.; Joos, M.; Lanni, F.; Lehmann Miotto, G.; Levinson, L.; Narevicius, J.; Panduro Vazquez, W.; Roich, A.; Ryu, S.; Schreuder, F.; Schumacher, J.; Vandelli, W.; Vermeulen, J.; Whiteson, D.; Wu, W.; Zhang, J.

2016-12-01

The ATLAS Phase-I upgrade (2019) requires a Trigger and Data Acquisition (TDAQ) system able to trigger and record data from up to three times the nominal LHC instantaneous luminosity. The Front-End LInk eXchange (FELIX) system provides an infrastructure to achieve this in a scalable, detector agnostic and easily upgradeable way. It is a PC-based gateway, interfacing custom radiation tolerant optical links from front-end electronics, via PCIe Gen3 cards, to a commodity switched Ethernet or InfiniBand network. FELIX enables reducing custom electronics in favour of software running on commercial servers. The FELIX system, the design of the PCIe prototype card and the integration test results are presented in this paper.

FELIX: a PCIe based high-throughput approach for interfacing front-end and trigger electronics in the ATLAS Upgrade framework

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00015561; Bauer, Kevin Thomas; Borga, Andrea; Boterenbrood, Henk; Chen, Hucheng; Chen, Kai; Drake, Gary; Donszelmann, Mark; Francis, David; Guest, Daniel; Gorini, Benedetto; Joos, Markus; Lanni, Francesco; Lehmann Miotto, Giovanna; Levinson, Lorne; Narevicius, Julia; Panduro Vazquez, William; Roich, Alexander; Ryu, Soo; Schreuder, Frans Philip; Schumacher, Jorn; Vandelli, Wainer; Vermeulen, Jos; Whiteson, Daniel; Wu, Weihao; Zhang, Jinlong

2016-01-01

The ATLAS Phase-I upgrade (2018) requires a Trigger and Data Acquisition (TDAQ) system able to trigger and record data from up to three times the nominal LHC instantaneous luminosity. The Front-End LInk eXchange (FELIX) system provides an infrastructure to achieve this in a scalable, detector agnostic and easily upgradeable way. It is a PC-based gateway, interfacing custom radiation tolerant optical links from front-end electronics, via FPGA PCIe Gen3 cards, to a commodity switched Ethernet or InfiniBand network. FELIX enables reducing custom electronics in favour of software running on commercial servers. The FELIX system, the design of the PCIe prototype card and the integration test results are presented in this paper.

FELIX: a PCIe based high-throughput approach for interfacing front-end and trigger electronics in the ATLAS Upgrade framework

International Nuclear Information System (INIS)

Anderson, J.; Drake, G.; Ryu, S.; Bauer, K.; Guest, D.; Borga, A.; Boterenbrood, H.; Schreuder, F.; Chen, H.; Chen, K.; Lanni, F.; Dönszelmann, M.; Francis, D.; Gorini, B.; Joos, M.; Miotto, G. Lehmann; Levinson, L.; Narevicius, J.; Roich, A.; Vazquez, W. Panduro

2016-01-01

The ATLAS Phase-I upgrade (2019) requires a Trigger and Data Acquisition (TDAQ) system able to trigger and record data from up to three times the nominal LHC instantaneous luminosity. The Front-End LInk eXchange (FELIX) system provides an infrastructure to achieve this in a scalable, detector agnostic and easily upgradeable way. It is a PC-based gateway, interfacing custom radiation tolerant optical links from front-end electronics, via PCIe Gen3 cards, to a commodity switched Ethernet or InfiniBand network. FELIX enables reducing custom electronics in favour of software running on commercial servers. The FELIX system, the design of the PCIe prototype card and the integration test results are presented in this paper.

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.

Triggering soft bombs at the LHC

Science.gov (United States)

Knapen, Simon; Griso, Simone Pagan; Papucci, Michele; Robinson, Dean J.

2017-08-01

Very high multiplicity, spherically-symmetric distributions of soft particles, with p T ˜ few×100 MeV, may be a signature of strongly-coupled hidden valleys that exhibit long, efficient showering windows. With traditional triggers, such `soft bomb' events closely resemble pile-up and are therefore only recorded with minimum bias triggers at a very low efficiency. We demonstrate a proof-of-concept for a high-level triggering strategy that efficiently separates soft bombs from pile-up by searching for a `belt of fire': a high density band of hits on the innermost layer of the tracker. Seeding our proposed high-level trigger with existing jet, missing transverse energy or lepton hardware-level triggers, we show that net trigger efficiencies of order 10% are possible for bombs of mass several × 100 GeV. We also consider the special case that soft bombs are the result of an exotic decay of the 125 GeV Higgs. The fiducial rate for `Higgs bombs' triggered in this manner is marginally higher than the rate achievable by triggering directly on a hard muon from associated Higgs production.

Calorimetry triggering in ATLAS

CERN Document Server

Igonkina, O; Adragna, P; Aharrouche, M; Alexandre, G; Andrei, V; Anduaga, X; Aracena, I; Backlund, S; Baines, J; Barnett, B M; Bauss, B; Bee, C; Behera, P; Bell, P; Bendel, M; Benslama, K; Berry, T; Bogaerts, A; Bohm, C; Bold, T; Booth, J R A; Bosman, M; Boyd, J; Bracinik, J; Brawn, I, P; Brelier, B; Brooks, W; Brunet, S; Bucci, F; Casadei, D; Casado, P; Cerri, A; Charlton, D G; Childers, J T; Collins, N J; Conde Muino, P; Coura Torres, R; Cranmer, K; Curtis, C J; Czyczula, Z; Dam, M; Damazio, D; Davis, A O; De Santo, A; Degenhardt, J; Delsart, P A; Demers, S; Demirkoz, B; Di Mattia, A; Diaz, M; Djilkibaev, R; Dobson, E; Dova, M, T; Dufour, M A; Eckweiler, S; Ehrenfeld, W; Eifert, T; Eisenhandler, E; Ellis, N; Emeliyanov, D; Enoque Ferreira de Lima, D; Faulkner, P J W; Ferland, J; Flacher, H; Fleckner, J E; Flowerdew, M; Fonseca-Martin, T; Fratina, S; Fhlisch, F; Gadomski, S; Gallacher, M P; Garitaonandia Elejabarrieta, H; Gee, C N P; George, S; Gillman, A R; Goncalo, R; Grabowska-Bold, I; Groll, M; Gringer, C; Hadley, D R; Haller, J; Hamilton, A; Hanke, P; Hauser, R; Hellman, S; Hidvgi, A; Hillier, S J; Hryn'ova, T; Idarraga, J; Johansen, M; Johns, K; Kalinowski, A; Khoriauli, G; Kirk, J; Klous, S; Kluge, E-E; Koeneke, K; Konoplich, R; Konstantinidis, N; Kwee, R; Landon, M; LeCompte, T; Ledroit, F; Lei, X; Lendermann, V; Lilley, J N; Losada, M; Maettig, S; Mahboubi, K; Mahout, G; Maltrana, D; Marino, C; Masik, J; Meier, K; Middleton, R P; Mincer, A; Moa, T; Monticelli, F; Moreno, D; Morris, J D; Mller, F; Navarro, G A; Negri, A; Nemethy, P; Neusiedl, A; Oltmann, B; Olvito, D; Osuna, C; Padilla, C; Panes, B; Parodi, F; Perera, V J O; Perez, E; Perez Reale, V; Petersen, B; Pinzon, G; Potter, C; Prieur, D P F; Prokishin, F; Qian, W; Quinonez, F; Rajagopalan, S; Reinsch, A; Rieke, S; Riu, I; Robertson, S; Rodriguez, D; Rogriquez, Y; Rhr, F; Saavedra, A; Sankey, D P C; Santamarina, C; Santamarina Rios, C; Scannicchio, D; Schiavi, C; Schmitt, K; Schultz-Coulon, H C; Schfer, U; Segura, E; Silverstein, D; Silverstein, S; Sivoklokov, S; Sjlin, J; Staley, R J; Stamen, R; Stelzer, J; Stockton, M C; Straessner, A; Strom, D; Sushkov, S; Sutton, M; Tamsett, M; Tan, C L A; Tapprogge, S; Thomas, J P; Thompson, P D; Torrence, E; Tripiana, M; Urquijo, P; Urrejola, P; Vachon, B; Vercesi, V; Vorwerk, V; Wang, M; Watkins, P M; Watson, A; Weber, P; Weidberg, T; Werner, P; Wessels, M; Wheeler-Ellis, S; Whiteson, D; Wiedenmann, W; Wielers, M; Wildt, M; Winklmeier, F; Wu, X; Xella, S; Zhao, L; Zobernig, H; de Seixas, J M; dos Anjos, A; Asman, B; Özcan, E

2009-01-01

The ATLAS experiment is preparing for data taking at 14 TeV collision energy. A rich discovery physics program is being prepared in addition to the detailed study of Standard Model processes which will be produced in abundance. The ATLAS multi-level trigger system is designed to accept one event in 2 105 to enable the selection of rare and unusual physics events. The ATLAS calorimeter system is a precise instrument, which includes liquid Argon electro-magnetic and hadronic components as well as a scintillator-tile hadronic calorimeter. All these components are used in the various levels of the trigger system. A wide physics coverage is ensured by inclusively selecting events with candidate electrons, photons, taus, jets or those with large missing transverse energy. The commissioning of the trigger system is being performed with cosmic ray events and by replaying simulated Monte Carlo events through the trigger and data acquisition system.

Wired and Wireless Camera Triggering with Arduino

Science.gov (United States)

Kauhanen, H.; Rönnholm, P.

2017-10-01

Synchronous triggering is an important task that allows simultaneous data capture from multiple cameras. Accurate synchronization enables 3D measurements of moving objects or from a moving platform. In this paper, we describe one wired and four wireless variations of Arduino-based low-cost remote trigger systems designed to provide a synchronous trigger signal for industrial cameras. Our wireless systems utilize 315 MHz or 434 MHz frequencies with noise filtering capacitors. In order to validate the synchronization accuracy, we developed a prototype of a rotating trigger detection system (named RoTriDeS). This system is suitable to detect the triggering accuracy of global shutter cameras. As a result, the wired system indicated an 8.91 μs mean triggering time difference between two cameras. Corresponding mean values for the four wireless triggering systems varied between 7.92 and 9.42 μs. Presented values include both camera-based and trigger-based desynchronization. Arduino-based triggering systems appeared to be feasible, and they have the potential to be extended to more complicated triggering systems.

Triggering for charm, beauty, and truth

International Nuclear Information System (INIS)

Appel, J.A.

1982-02-01

As the search for more and more rare processes accelerates, the need for more and more effective event triggers also accelerates. In the earliest experiments, a simple coincidence often sufficed not only as the event trigger, but as the complete record of an event of interest. In today's experiments, not only has the fast trigger become more sophisticated, but one or more additional level of trigger processing precedes writing event data to magnetic tape for later analysis. Further search experiments will certainly require further expansion in the number of trigger levels required to filter those rare events of particular interest

AIDS radio triggers.

Science.gov (United States)

Elias, A M

1991-07-01

In April 1991, the Ethnic Communities' Council of NSW was granted funding under the Community AIDS Prevention and Education Program through the Department of Community Services and Health, to produce a series of 6x50 second AIDS radio triggers with a 10-second tag line for further information. The triggers are designed to disseminate culturally-sensitive information about HIV/AIDS in English, Italian, Greek, Spanish, Khmer, Turkish, Macedonian, Serbo-Croatian, Arabic, Cantonese, and Vietnamese, with the goal of increasing awareness and decreasing the degree of misinformation about HIV/AIDS among people of non-English-speaking backgrounds through radio and sound. The 6 triggers cover the denial that AIDS exists in the community, beliefs that words and feelings do not protect one from catching HIV, encouraging friends to be compassionate, compassion within the family, AIDS information for a young audience, and the provision of accurate and honest information on HIV/AIDS. The triggers are slated to be completed by the end of July 1991 and will be broadcast on all possible community, ethnic, and commercial radio networks across Australia. They will be available upon request in composite form with an information kit for use by health care professionals and community workers.

Application of Vector Triggering Random Decrement

DEFF Research Database (Denmark)

Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

result is a Random Decrement function from each measurement. In traditional Random Decrement estimation the triggering condition is a scalar condition, which should only be fulfilled in a single measurement. In vector triggering Random Decrement the triggering condition is a vector condition......This paper deals with applications of the vector triggering Random Decrement technique. This technique is new and developed with the aim of minimizing estimation time and identification errors. The theory behind the technique is discussed in an accompanying paper. The results presented...... in this paper should be regarded as a further documentation of the technique. The key point in Random Decrement estimation is the formulation of a triggering condition. If the triggering condition is fulfilled a time segment from each measurement is picked out and averaged with previous time segments. The final...

Application of Vector Triggering Random Decrement

DEFF Research Database (Denmark)

Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

1997-01-01

result is a Random Decrement function from each measurement. In traditional Random Decrement estimation the triggering condition is a scalar condition, which should only be fulfilled in a single measurement. In vector triggering Random Decrement the triggering condition is a vector condition......This paper deals with applications of the vector triggering Random Decrement technique. This technique is new and developed with the aim of minimizing estimation time and identification errors. The theory behind the technique is discussed in an accompanying paper. The results presented...... in this paper should be regarded as a further documentation of the technique. The key point in Random Decrement estimation is the formulation of a triggering condition. If the triggering condition is fulfilled a time segment from each measurement is picked out and averaged with previous time segments. The final...

Operational performance of the ATLAS trigger and data acquisition system and its possible evolution

CERN Document Server

Negri, A; The ATLAS collaboration

2012-01-01

The experience accumulated in the ATLAS DAQ/HLT system operation during these years stimulated interest to explore possible evolutions, despite the success of the current design. One attractive direction is to merge three systems - the second trigger level (L2), the Event Builder (EB), and the Event Filter (EF) - within a single homogeneous one in which each HLT node executes all the steps required by the trigger and data acquisition process. Each L1 event is assigned to an available HLT node which executes the L2 algorithms using a subset of the event data and, upon positive selection, builds the event, which is further processed by the EF algorithms. Appealing aspects of this design are: a simplification of the software architecture and of its configuration, a better exploitation of the computing resources, the caching of fragments already collected for L2 processing, the automated load balancing between L2 and EF selection steps, the sharing of code and services on HLT nodes. Furthermore, the full treatmen...

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...

Geometrical Acceptance Analysis for RPC PAC Trigger

CERN Document Server

Seo, Eunsung

2010-01-01

The CMS(Compact Muon Solenoid) is one of the four experiments that will analyze the collision results of the protons accelerated by the Large Hardron Collider(LHC) at CERN(Conseil Europen pour la Recherche Nuclaire). In case of the CMS experiment, the trigger system is divided into two stages : The Level-1 Trigger and High Level Trigger. The RPC(Resistive Plate Chamber) PAC(PAttern Comparator) Trigger system, which is a subject of this thesis, is a part of the Level-1 Muon Trigger System. Main task of the PAC Trigger is to identify muons, measures transverse momenta and select the best muon candidates for each proton bunch collision occurring every 25 ns. To calculate the value of PAC Trigger efficiency for triggerable muon, two terms of different efficiencies are needed ; acceptance efficiency and chamber efficiency. Main goal of the works described in this thesis is obtaining the acceptance efficiency of the PAC Trigger in each logical cone. Acceptance efficiency is a convolution of the chambers geometry an...

Triggering the GRANDE array

International Nuclear Information System (INIS)

Wilson, C.L.; Bratton, C.B.; Gurr, J.; Kropp, W.; Nelson, M.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.

1990-01-01

A brief description of the Gamma Ray And Neutrino Detector Experiment (GRANDE) is presented. The detector elements and electronics are described. The trigger logic for the array is then examined. The triggers for the Gamma Ray and the Neutrino portions of the array are treated separately. (orig.)

Calorimetry triggering in ATLAS

International Nuclear Information System (INIS)

Igonkina, O; Achenbach, R; Andrei, V; Adragna, P; Aharrouche, M; Bauss, B; Bendel, M; Alexandre, G; Anduaga, X; Aracena, I; Backlund, S; Bogaerts, A; Baines, J; Barnett, B M; Bee, C; P, Behera; Bell, P; Benslama, K; Berry, T; Bohm, C

2009-01-01

The ATLAS experiment is preparing for data taking at 14 TeV collision energy. A rich discovery physics program is being prepared in addition to the detailed study of Standard Model processes which will be produced in abundance. The ATLAS multi-level trigger system is designed to accept one event in 2 | 10 5 to enable the selection of rare and unusual physics events. The ATLAS calorimeter system is a precise instrument, which includes liquid Argon electro-magnetic and hadronic components as well as a scintillator-tile hadronic calorimeter. All these components are used in the various levels of the trigger system. A wide physics coverage is ensured by inclusively selecting events with candidate electrons, photons, taus, jets or those with large missing transverse energy. The commissioning of the trigger system is being performed with cosmic ray events and by replaying simulated Monte Carlo events through the trigger and data acquisition system.

Calorimetry Triggering in ATLAS

International Nuclear Information System (INIS)

Igonkina, O.; Achenbach, R.; Adragna, P.; Aharrouche, M.; Alexandre, G.; Andrei, V.; Anduaga, X.; Aracena, I.; Backlund, S.; Baines, J.; Barnett, B.M.; Bauss, B.; Bee, C.; Behera, P.; Bell, P.; Bendel, M.; Benslama, K.; Berry, T.; Bogaerts, A.; Bohm, C.; Bold, T.; Booth, J.R.A.; Bosman, M.; Boyd, J.; Bracinik, J.; Brawn, I.P.; Brelier, B.; Brooks, W.; Brunet, S.; Bucci, F.; Casadei, D.; Casado, P.; Cerri, A.; Charlton, D.G.; Childers, J.T.; Collins, N.J.; Conde Muino, P.; Coura Torres, R.; Cranmer, K.; Curtis, C.J.; Czyczula, Z.; Dam, M.; Damazio, D.; Davis, A.O.; De Santo, A.; Degenhardt, J.

2011-01-01

The ATLAS experiment is preparing for data taking at 14 TeV collision energy. A rich discovery physics program is being prepared in addition to the detailed study of Standard Model processes which will be produced in abundance. The ATLAS multi-level trigger system is designed to accept one event in 2/10 5 to enable the selection of rare and unusual physics events. The ATLAS calorimeter system is a precise instrument, which includes liquid Argon electro-magnetic and hadronic components as well as a scintillator-tile hadronic calorimeter. All these components are used in the various levels of the trigger system. A wide physics coverage is ensured by inclusively selecting events with candidate electrons, photons, taus, jets or those with large missing transverse energy. The commissioning of the trigger system is being performed with cosmic ray events and by replaying simulated Monte Carlo events through the trigger and data acquisition system.

Calorimetry triggering in ATLAS

Energy Technology Data Exchange (ETDEWEB)

Igonkina, O [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Achenbach, R; Andrei, V [Kirchhoff Institut fuer Physik, Universitaet Heidelberg, Heidelberg (Germany); Adragna, P [Physics Department, Queen Mary, University of London, London (United Kingdom); Aharrouche, M; Bauss, B; Bendel, M [Institut fr Physik, Universitt Mainz, Mainz (Germany); Alexandre, G [Section de Physique, Universite de Geneve, Geneva (Switzerland); Anduaga, X [Universidad Nacional de La Plata, La Plata (Argentina); Aracena, I [Stanford Linear Accelerator Center (SLAC), Stanford (United States); Backlund, S; Bogaerts, A [European Laboratory for Particle Physics (CERN), Geneva (Switzerland); Baines, J; Barnett, B M [STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon (United Kingdom); Bee, C [Centre de Physique des Particules de Marseille, IN2P3-CNRS, Marseille (France); P, Behera [Iowa State University, Ames, Iowa (United States); Bell, P [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); Benslama, K [University of Regina, Regina (Canada); Berry, T [Department of Physics, Royal Holloway and Bedford New College, Egham (United Kingdom); Bohm, C [Fysikum, Stockholm University, Stockholm (Sweden)

2009-04-01

The ATLAS experiment is preparing for data taking at 14 TeV collision energy. A rich discovery physics program is being prepared in addition to the detailed study of Standard Model processes which will be produced in abundance. The ATLAS multi-level trigger system is designed to accept one event in 2 | 10{sup 5} to enable the selection of rare and unusual physics events. The ATLAS calorimeter system is a precise instrument, which includes liquid Argon electro-magnetic and hadronic components as well as a scintillator-tile hadronic calorimeter. All these components are used in the various levels of the trigger system. A wide physics coverage is ensured by inclusively selecting events with candidate electrons, photons, taus, jets or those with large missing transverse energy. The commissioning of the trigger system is being performed with cosmic ray events and by replaying simulated Monte Carlo events through the trigger and data acquisition system.

The DOe Silicon Track Trigger

International Nuclear Information System (INIS)

Steinbrueck, Georg

2003-01-01

We describe a trigger preprocessor to be used by the DOe experiment for selecting events with tracks from the decay of long-lived particles. This Level 2 impact parameter trigger utilizes information from the Silicon Microstrip Tracker to reconstruct tracks with improved spatial and momentum resolutions compared to those obtained by the Level 1 tracking trigger. It is constructed of VME boards with much of the logic existing in programmable processors. A common motherboard provides the I/O infrastructure and three different daughter boards perform the tasks of identifying the roads from the tracking trigger data, finding the clusters in the roads in the silicon detector, and fitting tracks to the clusters. This approach provides flexibility for the design, testing and maintenance phases of the project. The track parameters are provided to the trigger framework in 25 μs. The effective impact parameter resolution for high-momentum tracks is 35 μm, dominated by the size of the Tevatron beam

The ATLAS hadronic tau trigger

International Nuclear Information System (INIS)

Shamim, Mansoora

2012-01-01

The extensive tau physics programs of the ATLAS experiment relies heavily on trigger to select hadronic decays of tau lepton. Such a trigger is implemented in ATLAS to efficiently collect signal events, while keeping the rate of multi-jet background within the allowed bandwidth. This contribution summarizes the performance of the ATLAS hadronic tau trigger system during 2011 data taking period and improvements implemented for the 2012 data collection.

Global search of triggered non-volcanic tremor

Science.gov (United States)

Chao, Tzu-Kai Kevin

Deep non-volcanic tremor is a newly discovered seismic phenomenon with low amplitude, long duration, and no clear P- and S-waves as compared with regular earthquake. Tremor has been observed at many major plate-boundary faults, providing new information about fault slip behaviors below the seismogenic zone. While tremor mostly occurs spontaneously (ambient tremor) or during episodic slow-slip events (SSEs), sometimes tremor can also be triggered during teleseismic waves of distance earthquakes, which is known as "triggered tremor". The primary focus of my Ph.D. work is to understand the physical mechanisms and necessary conditions of triggered tremor by systematic investigations in different tectonic regions. In the first chapter of my dissertation, I conduct a systematic survey of triggered tremor beneath the Central Range (CR) in Taiwan for 45 teleseismic earthquakes from 1998 to 2009 with Mw ≥ 7.5. Triggered tremors are visually identified as bursts of high-frequency (2-8 Hz), non-impulsive, and long-duration seismic energy that are coherent among many seismic stations and modulated by the teleseismic surface waves. A total of 9 teleseismic earthquakes has triggered clear tremor in Taiwan. The peak ground velocity (PGV) of teleseismic surface waves is the most important factor in determining tremor triggering potential, with an apparent threshold of ˜0.1 cm/s, or 7-8 kPa. However, such threshold is partially controlled by the background noise level, preventing triggered tremor with weaker amplitude from being observed. In addition, I find a positive correlation between the PGV and the triggered tremor amplitude, which is consistent with the prediction of the 'clock-advance' model. This suggests that triggered tremor can be considered as a sped-up occurrence of ambient tremor under fast loading from the passing surface waves. Finally, the incident angles of surface waves also play an important rule in controlling the tremor triggering potential. The next

The CLEO-III Trigger: Decision and gating

International Nuclear Information System (INIS)

Bergfeld, T.J.; Gollin, G.D.; Haney, M.J.

1996-01-01

The CLEO-III Trigger provides a trigger decision every 42ns, with a latency of approximately 2.5μs. This paper describes the free-running, pipelined trigger decision logic, the throttling mechanism whereby the data acquisition system can modulate the trigger rate to maximize throughput without buffer overrun, and the subsequent signal distribution mechanism for delivering the trigger decision to the front-end electronics. This paper also describes the multilevel simulation methods employed to allow detailed low-level models of trigger components to be co-simulated with more abstract system models, thus allowing full system modeling without incurring prohibitive computational overheads

Triggers in UA2 and UA1

International Nuclear Information System (INIS)

Dorenbosch, J.

1985-01-01

The UA2 and UA1 trigger systems are described as they will be used after the upgrade of the CERN SPPS. The luminosity of the collider will increase to 3x10 30 . The bunch spacing is 4 microseconds, comparable to the time available for a second level trigger at the SSC. The first level triggers are very powerful and deliver trigger rates of about 100 Hz. The UA1 second level trigger operates on the final digitizings with a combination of special and general purpose processors. At the highest trigger levels a small farm of processors performs the final reduction. (orig.)

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.)

The ZEUS calorimeter first level trigger

International Nuclear Information System (INIS)

Smith, W.H.; Ali, I.; Behrens, B.; Fordham, C.; Foudas, C.; Goussiou, A.; Jaworski, M.; Kinnel, T.; Lackey, J.; Robl, P.; Silverstein, S.; Dawson, J.W.; Krakauer, D.A.; Talaga, R.L.; Schlereth, J.L.

1994-10-01

The design of the ZEUS Calorimeter First Level Trigger (CFLT) is presented. The CFLT utilizes a pipelined architecture to provide trigger data for a global first leel trigger decision 5 μsec after each beam crossing, occurring every 96 nsec. The charges from 13K phototubes are summed into 1792 trigger tower pulseheights which are digitized by flash ADC's. The digital values are linearized, stored and used for sums and pattern tests. Summary data is forwarded to the Global First Level Trigger for each crossing 2 μsec after the crossing occurred. The CFLT determines the total energy, the total transverse energy, the missing energy, and the energy and number of isolated electrons and muons. It also provides information on the electromagnetic and hadronic energy deposited in various regions of the calorimeter. The CFLT has kept the experimental trigger rate below ∼200 Hz at the highest luminosity experienced at HERA. Performance studies suggest that the CFLT will keep the trigger rate below 1 kHZ against a rate of proton-beam gas interactions on the order of the 100 kHz expected at design luminosity. (orig.)

LHCb: LHCb High Level Trigger design issues for post Long Stop 1 running

CERN Multimedia

Albrecht, J; Raven, G; Sokoloff, M D; Williams, M

2013-01-01

The LHCb High Level Trigger uses two stages of software running on an Event Filter Farm (EFF) to select events for offline reconstruction and analysis. The first stage (Hlt1) processes approximately 1 MHz of events accepted by a hardware trigger. In 2012, the second stage (Hlt2) wrote 5 kHz to permanent storage for later processing. Following the LHC's Long Stop 1 (anticipated for 2015), the machine energy will increase from 8 TeV in the center-of-mass to 13 TeV and the cross sections for beauty and charm are expected to grow proportionately. We plan to increase the Hlt2 output to 12 kHz, some for immediate offline processing, some for later offline processing, and some ready for immediate analysis. By increasing the absolute computing power of the EFF, and buffering data for processing between machine fills, we should be able to significantly increase the efficiency for signal while improving signal-to-background ratios. In this poster we will present several strategies under consideration and some of th...

A trigger simulation framework for the ALICE experiment

International Nuclear Information System (INIS)

Antinori, F; Carminati, F; Gheata, A; Gheata, M

2011-01-01

A realistic simulation of the trigger system in a complex HEP experiment is essential for performing detailed trigger efficiency studies. The ALICE trigger simulation is evolving towards a framework capable of replaying the full trigger chain starting from the input to the individual trigger processors and ending with the decision mechanisms of the ALICE central trigger processor. This paper describes the new ALICE trigger simulation framework that is being tested and deployed. The framework handles details like trigger levels, signal delays and busy signals, implementing the trigger logic via customizable trigger device objects managed by a robust scheduling mechanism. A big advantage is the high flexibility of the framework, which is able to mix together components described with very different levels of detail. The framework is being gradually integrated within the ALICE simulation and reconstruction frameworks.

Global Software Engineering: A Software Process Approach

Science.gov (United States)

Richardson, Ita; Casey, Valentine; Burton, John; McCaffery, Fergal

Our research has shown that many companies are struggling with the successful implementation of global software engineering, due to temporal, cultural and geographical distance, which causes a range of factors to come into play. For example, cultural, project managementproject management and communication difficulties continually cause problems for software engineers and project managers. While the implementation of efficient software processes can be used to improve the quality of the software product, published software process models do not cater explicitly for the recent growth in global software engineering. Our thesis is that global software engineering factors should be included in software process models to ensure their continued usefulness in global organisations. Based on extensive global software engineering research, we have developed a software process, Global Teaming, which includes specific practices and sub-practices. The purpose is to ensure that requirements for successful global software engineering are stipulated so that organisations can ensure successful implementation of global software engineering.

Trigger Menu in 2017

CERN Document Server

The ATLAS collaboration

2018-01-01

This document summarises the trigger menu deployed by the ATLAS experiment during 2017 data taking at proton-proton collision centre-of-mass energies of $\\sqrt{s}=13$ TeV and $\\sqrt{s}=5$ TeV at the LHC and describes the improvements with respect to the trigger system and menu used in 2016 data taking.

Intelligent trigger processor for the crystal box

International Nuclear Information System (INIS)

Sanders, G.H.; Butler, H.S.; Cooper, M.D.

1981-01-01

A large solid angle modular NaI(Tl) detector with 432 phototubes and 88 trigger scintillators is being used to search simultaneously for three lepton flavor changing decays of muon. A beam of up to 10 6 muons stopping per second with a 6% duty factor would yield up to 1000 triggers per second from random triple coincidences. A reduction of the trigger rate to 10 Hz is required from a hardwired primary trigger processor described in this paper. Further reduction to < 1 Hz is achieved by a microprocessor based secondary trigger processor. The primary trigger hardware imposes voter coincidence logic, stringent timing requirements, and a non-adjacency requirement in the trigger scintillators defined by hardwired circuits. Sophisticated geometric requirements are imposed by a PROM-based matrix logic, and energy and vector-momentum cuts are imposed by a hardwired processor using LSI flash ADC's and digital arithmetic loci. The secondary trigger employs four satellite microprocessors to do a sparse data scan, multiplex the data acquisition channels and apply additional event filtering

A field study on root cause analysis of defects in space software

International Nuclear Information System (INIS)

Silva, Nuno; Cunha, João Carlos; Vieira, Marco

2017-01-01

Critical systems, such as space systems, are developed under strict requirements envisaging high integrity in accordance to specific standards. For such software systems, an independent assessment is put into effect (Independent Software Verification and Validation – ISVV) after the regular development lifecycle and V&V activities, aiming at finding residual faults and raising confidence in the software. However, it has been observed that there is still a significant number of defects remaining at this stage, questioning the effectiveness of the previous engineering processes. This paper presents a root cause analysis of 1070 defects found in four space software projects during ISVV, by applying an improved Orthogonal Defect Classification (ODC) taxonomy and examining the defect types, triggers and impacts, in order to identify why they reached such a later stage in the development. The paper also puts forward proposals for modifications to both the software development (to prevent defects) and the V&V activities (to better detect defects) and an assessment methodology for future works on root cause analysis. - Highlights: • Root cause analysis of space software defects by using an enhanced ODC taxonomy. • Prioritization of the root causes according to the more important defect impacts. • Identification of improvements to systems engineering and development processes. • Improvements to V&V activities as means to reduce the occurrence of defects. • Generic process to achieve the defects root causes and the corrections suggestions.

What does built-in software of home ventilators tell us? An observational study of 150 patients on home ventilation.

Science.gov (United States)

Pasquina, Patrick; Adler, Dan; Farr, Pamela; Bourqui, Pascale; Bridevaux, Pierre Olivier; Janssens, Jean-Paul

2012-01-01

Recent home ventilators are equipped with built-in software which provides data such as compliance, estimations of leaks, tidal volume, minute ventilation, respiratory rate, apnea and apnea-hypopnea indexes, and percentage of inspirations triggered by the patient (or ventilator). However, for many of these variables, there is neither consensus nor documentation as to what is to be expected in a population of stable patients under noninvasive ventilation (NIV). To document the values and distribution of specific items downloaded from ventilator monitoring software, by diagnostic category. Analysis of data downloaded from home ventilators in clinically stable patients under long-term NIV, during elective home visits by specialized nurses. Data were collected from home ventilators of 150 patients with chronic obstructive pulmonary disease (n = 32), overlap syndrome (n = 29), obesity-hypoventilation (n = 38), neuromuscular disorders (n = 19), restrictive disorders (n = 21), and central sleep apnea syndrome (n = 11). On average, leaks were low, being lowest in patients with facial masks (vs. nasal masks), and increased with older age. Compliance was excellent in all groups. Patients with neuromuscular diseases triggered their ventilators less and tended to be 'captured', while other groups triggered at least half of inspiratory cycles. Most patients had a respiratory rate just slightly above the back-up rate. Residual apneas and hypopneas were highest in patients with central apneas. Built-in software of home ventilators provides the clinician with new parameters, some of which are a useful adjunct to recommended tools for monitoring NIV and may contribute to a better understanding of residual hypoventilation and/or desaturations. However, an independent validation of the accuracy of this information is mandatory. Copyright © 2011 S. Karger AG, Basel.

Investigation of index finger triggering force using a cadaver experiment: Effects of trigger grip span, contact location, and internal tendon force.

Science.gov (United States)

Chang, Joonho; Freivalds, Andris; Sharkey, Neil A; Kong, Yong-Ku; Mike Kim, H; Sung, Kiseok; Kim, Dae-Min; Jung, Kihyo

2017-11-01

A cadaver study was conducted to investigate the effects of triggering conditions (trigger grip span, contact location, and internal tendon force) on index finger triggering force and the force efficiency of involved tendons. Eight right human cadaveric hands were employed, and a motion simulator was built to secure and control the specimens. Index finger triggering forces were investigated as a function of different internal tendon forces (flexor digitorum profundus + flexor digitorum superficialis = 40, 70, and 100 N), trigger grip spans (40, 50, and 60 mm), and contact locations between the index finger and a trigger. Triggering forces significantly increased when internal tendon forces increased from 40 to 100 N. Also, trigger grip spans and contact locations had significant effects on triggering forces; maximum triggering forces were found at a 50 mm span and the most proximal contact location. The results revealed that only 10-30% of internal tendon forces were converted to their external triggering forces. Copyright © 2017 Elsevier Ltd. All rights reserved.

Software engineering architecture-driven software development

CERN Document Server

Schmidt, Richard F

2013-01-01

Software Engineering: Architecture-driven Software Development is the first comprehensive guide to the underlying skills embodied in the IEEE's Software Engineering Body of Knowledge (SWEBOK) standard. Standards expert Richard Schmidt explains the traditional software engineering practices recognized for developing projects for government or corporate systems. Software engineering education often lacks standardization, with many institutions focusing on implementation rather than design as it impacts product architecture. Many graduates join the workforce with incomplete skil

LHCb base-line level-0 trigger 3D-Flow implementation

International Nuclear Information System (INIS)

Crosetto, Dario B.

1999-01-01

shorter than 1.5 m. Full implementation of a 3D-Flow system, for the most complex trigger algorithm, requires 320 cables to north and south crates and 40 cables to east and west crates (Cable cost=$2 each). For applications requiring a simpler real-time algorithm (e.g., requiring less than 20 steps, which is equivalent to 10 layers of 3D-Flow processors), then the number of connections for the inter-boards (North and South), and inter-crates (East and West) will also be reduced to the number of layers used by the simpler algorithm, thus not requiring to install all cables (e.g., applications requiring only nine layers of 3D-Flow processors will save 32 cables to the North, 32 to the South, four to the East, and four to the West crates). Details are also given on timing and synchronization issues, ASIC design verification, real-time performance monitoring and design (software and hardware) development tools

Hierarchical trigger of the ALICE calorimeters

CERN Document Server

Muller, Hans; Novitzky, Norbert; Kral, Jiri; Rak, Jan; Schambach, Joachim; Wang, Ya-Ping; Wang, Dong; Zhou, Daicui

2010-01-01

The trigger of the ALICE electromagnetic calorimeters is implemented in 2 hierarchically connected layers of electronics. In the lower layer, level-0 algorithms search shower energy above threshold in locally confined Trigger Region Units (TRU). The top layer is implemented as a single, global trigger unit that receives the trigger data from all TRUs as input to the level-1 algorithm. This architecture was first developed for the PHOS high pT photon trigger before it was adopted by EMCal also for the jet trigger. TRU units digitize up to 112 analogue input signals from the Front End Electronics (FEE) and concentrate their digital stream in a single FPGA. A charge and time summing algorithm is combined with a peakfinder that suppresses spurious noise and is precise to single LHC bunches. With a peak-to-peak noise level of 150 MeV the linear dynamic range above threshold spans from MIP energies at 215 up to 50 GeV. Local level-0 decisions take less than 600 ns after LHC collisions, upon which all TRUs transfer ...

Level-1 Calorimeter Trigger starts firing

CERN Multimedia

Stephen Hillier

2007-01-01

L1Calo is one of the major components of ATLAS First Level trigger, along with the Muon Trigger and Central Trigger Processor. It forms all of the first-level calorimeter-based triggers, including electron, jet, tau and missing ET. The final system consists of over 250 custom designed 9U VME boards, most containing a dense array of FPGAs or ASICs. It is subdivided into a PreProcessor, which digitises the incoming trigger signals from the Liquid Argon and Tile calorimeters, and two separate processor systems, which perform the physics algorithms. All of these are highly flexible, allowing the possibility to adapt to beam conditions and luminosity. All parts of the system are read out through Read-Out Drivers, which provide monitoring data and Region of Interest (RoI) information for the Level-2 trigger. Production of the modules is now essentially complete, and enough modules exist to populate the full scale system in USA15. Installation is proceeding rapidly - approximately 90% of the final modules are insta...

Software FMEA analysis for safety-related application software

International Nuclear Information System (INIS)

Park, Gee-Yong; Kim, Dong Hoon; Lee, Dong Young

2014-01-01

Highlights: • We develop a modified FMEA analysis suited for applying to software architecture. • A template for failure modes on a specific software language is established. • A detailed-level software FMEA analysis on nuclear safety software is presented. - Abstract: A method of a software safety analysis is described in this paper for safety-related application software. The target software system is a software code installed at an Automatic Test and Interface Processor (ATIP) in a digital reactor protection system (DRPS). For the ATIP software safety analysis, at first, an overall safety or hazard analysis is performed over the software architecture and modules, and then a detailed safety analysis based on the software FMEA (Failure Modes and Effect Analysis) method is applied to the ATIP program. For an efficient analysis, the software FMEA analysis is carried out based on the so-called failure-mode template extracted from the function blocks used in the function block diagram (FBD) for the ATIP software. The software safety analysis by the software FMEA analysis, being applied to the ATIP software code, which has been integrated and passed through a very rigorous system test procedure, is proven to be able to provide very valuable results (i.e., software defects) that could not be identified during various system tests

MR imaging findings of trigger thumb

Energy Technology Data Exchange (ETDEWEB)

Chang, Eric Y.; Chen, Karen C.; Chung, Christine B. [VA San Diego Healthcare System, Radiology Service, San Diego, CA (United States); University of California, San Diego Medical Center, Department of Radiology, San Diego, CA (United States)

2015-08-15

Trigger finger (or trigger thumb), also known as sclerosing tenosynovitis, is a common clinical diagnosis that rarely presents for imaging. Because of this selection bias, many radiologists may not be familiar with the process. Furthermore, patients who do present for imaging frequently have misleading examination indications. To our knowledge, magnetic resonance (MR) imaging findings of trigger thumb have not been previously reported in the literature. In this article, we review the entity of trigger thumb, the anatomy involved, and associated imaging findings, which include flexor pollicis longus tendinosis with a distinct nodule, A1 pulley thickening, and tenosynovitis. In addition, in some cases, an abnormal Av pulley is apparent. In the rare cases of trigger finger that present for MR imaging, accurate diagnosis by the radiologist can allow initiation of treatment and avoid further unnecessary workup. (orig.)

MR imaging findings of trigger thumb

International Nuclear Information System (INIS)

Chang, Eric Y.; Chen, Karen C.; Chung, Christine B.

2015-01-01

Trigger finger (or trigger thumb), also known as sclerosing tenosynovitis, is a common clinical diagnosis that rarely presents for imaging. Because of this selection bias, many radiologists may not be familiar with the process. Furthermore, patients who do present for imaging frequently have misleading examination indications. To our knowledge, magnetic resonance (MR) imaging findings of trigger thumb have not been previously reported in the literature. In this article, we review the entity of trigger thumb, the anatomy involved, and associated imaging findings, which include flexor pollicis longus tendinosis with a distinct nodule, A1 pulley thickening, and tenosynovitis. In addition, in some cases, an abnormal Av pulley is apparent. In the rare cases of trigger finger that present for MR imaging, accurate diagnosis by the radiologist can allow initiation of treatment and avoid further unnecessary workup. (orig.)

Verification and Diagnostics Framework in ATLAS Trigger/DAQ

CERN Document Server

Barczyk, M.; Caprini, M.; Da Silva Conceicao, J.; Dobson, M.; Flammer, J.; Jones, R.; Kazarov, A.; Kolos, S.; Liko, D.; Lucio, L.; Mapelli, L.; Soloviev, I.; Hart, R.; Amorim, A.; Klose, D.; Lima, J.; Pedro, J.; Wolters, H.; Badescu, E.; Alexandrov, I.; Kotov, V.; Mineev, M.; Ryabov, Yu.; Ryabov, Yu.

2003-01-01

Trigger and data acquisition (TDAQ) systems for modern HEP experiments are composed of thousands of hardware and software components depending on each other in a very complex manner. Typically, such systems are operated by non-expert shift operators, which are not aware of system functionality details. It is therefore necessary to help the operator to control the system and to minimize system down-time by providing knowledge-based facilities for automatic testing and verification of system components and also for error diagnostics and recovery. For this purpose, a verification and diagnostic framework was developed in the scope of ATLAS TDAQ. The verification functionality of the framework allows developers to configure simple low-level tests for any component in a TDAQ configuration. The test can be configured as one or more processes running on different hosts. The framework organizes tests in sequences, using knowledge about components hierarchy and dependencies, and allowing the operator to verify the fun...

Trigger processing using reconfigurable logic in the CMS calorimeter trigger

Energy Technology Data Exchange (ETDEWEB)

Brooke, J J; Cussans, D G; Heath, G P; Maddox, A J; Newbold, D M; Rabbetts, P D

2001-04-01

We present the design of the Global Calorimeter Trigger processor for the CMS detector at LHC. This is a fully pipelined processor system which collects data from all the CMS calorimeters and produces summary information used in forming the Level-1 trigger decision for each event. The design in based on the use of state-of-the-art reconfigurable logic devices (FPGAs) and fast data links. We present the results of device testing using a low-latency pipelined sort algorithm, which demonstrate that an FPGA can be used to perform processing previously foreseen to require custom ASICs. Our design approach results in a powerful, flexible and compact processor system.

Trigger Finger

Science.gov (United States)

... in a bent position. People whose work or hobbies require repetitive gripping actions are at higher risk ... developing trigger finger include: Repeated gripping. Occupations and hobbies that involve repetitive hand use and prolonged gripping ...

Triggers for a high sensitivity charm experiment

International Nuclear Information System (INIS)

Christian, D.C.

1994-07-01

Any future charm experiment clearly should implement an E T trigger and a μ trigger. In order to reach the 10 8 reconstructed charm level for hadronic final states, a high quality vertex trigger will almost certainly also be necessary. The best hope for the development of an offline quality vertex trigger lies in further development of the ideas of data-driven processing pioneered by the Nevis/U. Mass. group

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.

D0 triggering and data acquisition

International Nuclear Information System (INIS)

Gibbard, B.

1992-10-01

The trigger for D0 is a multi-tier system. Within the 3.5 μsec bunch crossing interval, custom electronics select interesting event candidates based on electromagnetic and hadronic energy deposits in the calorimeter and on indications of tracks in the muon system. Subsequent hardware decisions use refined calculations of electron and muon characteristics. The highest level trigger occurs in one element of a farm of microprocessors, where fully developed algorithms for electrons, muons, jets, or missing E t are executed. This highest level trigger also provides the assembly of the event into its final data structure. Performance of this trigger and data acquisition system in collider operation is described

Sandia software guidelines: Software quality planning

Energy Technology Data Exchange (ETDEWEB)

1987-08-01

This volume is one in a series of Sandia Software Guidelines intended for use in producing quality software within Sandia National Laboratories. In consonance with the IEEE Standard for Software Quality Assurance Plans, this volume identifies procedures to follow in producing a Software Quality Assurance Plan for an organization or a project, and provides an example project SQA plan. 2 figs., 4 tabs.

The STAR Level-3 trigger system

International Nuclear Information System (INIS)

Adler, C.; Berger, J.; Demello, M.; Dietel, T.; Flierl, D.; Landgraf, J.; Lange, J.S.; LeVine, M.J.; Ljubicic, A.; Nelson, J.; Roehrich, D.; Stock, R.; Struck, C.; Yepes, P.

2003-01-01

The STAR Level-3 trigger issues a trigger decision upon a complete online reconstruction of Au+Au collisions at relativistic heavy ion collider energies. Central interactions are processed up to a rate of 50 s -1 including a simple analysis of physics observables. The setup of the processor farm and the event reconstruction as well as experiences and the proposed trigger algorithms are described

A Novel in situ Trigger Combination Method

International Nuclear Information System (INIS)

Buzatu, Adrian; Warburton, Andreas; Krumnack, Nils; Yao, Wei-Ming

2012-01-01

Searches for rare physics processes using particle detectors in high-luminosity colliding hadronic beam environments require the use of multi-level trigger systems to reject colossal background rates in real time. In analyses like the search for the Higgs boson, there is a need to maximize the signal acceptance by combining multiple different trigger chains when forming the offline data sample. In such statistically limited searches, datasets are often amassed over periods of several years, during which the trigger characteristics evolve and their performance can vary significantly. Reliable production cross-section measurements and upper limits must take into account a detailed understanding of the effective trigger inefficiency for every selected candidate event. We present as an example the complex situation of three trigger chains, based on missing energy and jet energy, to be combined in the context of the search for the Higgs (H) boson produced in association with a W boson at the Collider Detector at Fermilab (CDF). We briefly review the existing techniques for combining triggers, namely the inclusion, division, and exclusion methods. We introduce and describe a novel fourth in situ method whereby, for each candidate event, only the trigger chain with the highest a priori probability of selecting the event is considered. The in situ combination method has advantages of scalability to large numbers of differing trigger chains and of insensitivity to correlations between triggers. We compare the inclusion and in situ methods for signal event yields in the CDF WH search.

Software development based on high speed PC oscilloscope for automated pulsed magnetic field measurement system

International Nuclear Information System (INIS)

Sun Yuxiang; Shang Lei; Li Ji; Ge Lei

2011-01-01

It introduces a method of a software development which is based on high speed PC oscilloscope for pulsed magnetic field measurement system. The previous design has been improved by this design, high-speed virtual oscilloscope has been used in the field for the first time. In the design, the automatic data acquisition, data process, data analysis and storage have been realized. Automated point checking reduces the workload. The use of precise motion bench increases the positioning accuracy. The software gets the data from PC oscilloscope by calling DLLs and includes the function of oscilloscope, such as trigger, ranges, and sample rate setting etc. Spline Interpolation and Bandstop Filter are used to denoise the signals. The core of the software is the state machine which controls the motion of stepper motors and data acquisition and stores the data automatically. NI Vision Acquisition Software and Database Connectivity Toolkit make the video surveillance of laboratory and MySQL database connectivity available. The raw signal and processed signal have been compared in this paper. The waveform has been greatly improved by the signal processing. (authors)

Discrete element modeling of triggered slip in faults with granular gouge: application to dynamic earthquake triggering

International Nuclear Information System (INIS)

Ferdowsi, B.

2014-01-01

Recent seismological observations based on new, more sensitive instrumentation show that seismic waves radiated from large earthquakes can trigger other earthquakes globally. This phenomenon is called dynamic earthquake triggering and is well-documented for over 30 of the largest earthquakes worldwide. Granular materials are at the core of mature earthquake faults and play a key role in fault triggering by exhibiting a rich nonlinear response to external perturbations. The stick-slip dynamics in sheared granular layers is analogous to the seismic cycle for earthquake fault systems. In this research effort, we characterize the macroscopic scale statistics and the grain-scale mechanisms of triggered slip in sheared granular layers. We model the granular fault gouge using three dimensional discrete element method simulations. The modeled granular system is put into stick-slip dynamics by applying a conning pressure and a shear load. The dynamic triggering is simulated by perturbing the spontaneous stick-slip dynamics using an external vibration applied to the boundary of the layer. The influences of the triggering consist in a frictional weakening during the vibration interval, a clock advance of the next expected large slip event and long term effects in the form of suppression and recovery of the energy released from the granular layer. Our study suggests that above a critical amplitude, vibration causes a significant clock advance of large slip events. We link this clock advance to a major decline in the slipping contact ratio as well as a decrease in shear modulus and weakening of the granular gouge layer. We also observe that shear vibration is less effective in perturbing the stick-slip dynamics of the granular layer. Our study suggests that in order to have an effective triggering, the input vibration must also explore the granular layer at length scales about or less than the average grain size. The energy suppression and the subsequent recovery and increased

Upgrade of the CMS Global Muon Trigger

CERN Document Server

Jeitler, Manfred; Rabady, Dinyar; Sakulin, Hannes; Stahl, Achim

2015-01-01

The increase in center-of-mass energy and luminosity for Run-II of the Large Hadron Collider poses new challenges for the trigger systems of the experiments. To keep triggering with a similar performance as in Run-I, the CMS muon trigger is currently being upgraded. The new algorithms will provide higher resolution, especially for the muon transverse momentum and will make use of isolation criteria that combine calorimeter with muon information already in the level-1 trigger. The demands of the new algorithms can only be met by upgrading the level-1 trigger system to new powerful FPGAs with high bandwidth I/O. The processing boards will be based on the new μTCA standard. We report on the planned algorithms for the upgraded Global Muon Trigger (μGMT) which sorts and removes duplicates from boundaries of the muon trigger sub-systems. Furthermore, it determines how isolated the muon candidates are based on calorimetric energy deposits. The μGMT will be implemented using a processing board that features a larg...

Upgrade of the CMS Global Muon Trigger

CERN Document Server

Lingemann, Joschka; Sakulin, Hannes; Jeitler, Manfred; Stahl, Achim

2015-01-01

The increase in center-of-mass energy and luminosity for Run 2 of the Large Hadron Collider pose new challenges for the trigger systems of the experiments. To keep triggering with a similar performance as in Run 1, the CMS muon trigger is currently being upgraded. The new algorithms will provide higher resolution, especially for the muon transverse momentum and will make use of isolation criteria that combine calorimeter with muon information already in the level-1 trigger. The demands of the new algorithms can only be met by upgrading the level-1 trigger system to new powerful FPGAs with high bandwidth I/O. The processing boards will be based on the new microTCA standard. We report on the planned algorithms for the upgraded Global Muon Trigger (GMT) which combines information from the muon trigger sub-systems and assigns the isolation variable. The upgraded GMT will be implemented using a Master Processor 7 card, built by Imperial College, that features a large Xilinx Virtex 7 FPGA. Up to 72 optical links at...

Software

Energy Technology Data Exchange (ETDEWEB)

Macedo, R.; Budd, G.; Ross, E.; Wells, P.

2010-07-15

The software section of this journal presented new software programs that have been developed to help in the exploration and development of hydrocarbon resources. Software provider IHS Inc. has made additions to its geological and engineering analysis software tool, IHS PETRA, a product used by geoscientists and engineers to visualize, analyze and manage well production, well log, drilling, reservoir, seismic and other related information. IHS PETRA also includes a directional well module and a decline curve analysis module to improve analysis capabilities in unconventional reservoirs. Petris Technology Inc. has developed a software to help manage the large volumes of data. PetrisWinds Enterprise (PWE) helps users find and manage wellbore data, including conventional wireline and MWD core data; analysis core photos and images; waveforms and NMR; and external files documentation. Ottawa-based Ambercore Software Inc. has been collaborating with Nexen on the Petroleum iQ software for steam assisted gravity drainage (SAGD) producers. Petroleum iQ integrates geology and geophysics data with engineering data in 3D and 4D. Calgary-based Envirosoft Corporation has developed a software that reduces the costly and time-consuming effort required to comply with Directive 39 of the Alberta Energy Resources Conservation Board. The product includes an emissions modelling software. Houston-based Seismic Micro-Technology (SMT) has developed the Kingdom software that features the latest in seismic interpretation. Holland-based Joa Oil and Gas and Calgary-based Computer Modelling Group have both supplied the petroleum industry with advanced reservoir simulation software that enables reservoir interpretation. The 2010 software survey included a guide to new software applications designed to facilitate petroleum exploration, drilling and production activities. Oil and gas producers can use the products for a range of functions, including reservoir characterization and accounting. In

Upgrade trigger: Biannual performance update

CERN Document Server

Aaij, Roel; Couturier, Ben; Esen, Sevda; De Cian, Michel; De Vries, Jacco Andreas; Dziurda, Agnieszka; Fitzpatrick, Conor; Fontana, Marianna; Grillo, Lucia; Hasse, Christoph; Jones, Christopher Rob; Le Gac, Renaud; Matev, Rosen; Neufeld, Niko; Nikodem, Thomas; Polci, Francesco; Del Buono, Luigi; Quagliani, Renato; Schwemmer, Rainer; Seyfert, Paul; Stahl, Sascha; Szumlak, Tomasz; Vesterinen, Mika Anton; Wanczyk, Joanna; Williams, Mark Richard James; Yin, Hang; Zacharjasz, Emilia Anna

2017-01-01

This document presents the performance of the LHCb Upgrade trigger reconstruction sequence, incorporating changes to the underlying reconstruction algorithms and detector description since the Trigger and Online Upgrade TDR. An updated extrapolation is presented using the most recent example of an Event Filter Farm node.

Triggered Release from Polymer Capsules

Energy Technology Data Exchange (ETDEWEB)

Esser-Kahn, Aaron P. [Univ. of Illinois, Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology and Dept. of Chemistry; Odom, Susan A. [Univ. of Illinois, Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology and Dept. of Chemistry; Sottos, Nancy R. [Univ. of Illinois, Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology and Dept. of Materials Science and Engineering; White, Scott R. [Univ. of Illinois, Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology and Dept. of Aerospace Engineering; Moore, Jeffrey S. [Univ. of Illinois, Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology and Dept. of Chemistry

2011-07-06

Stimuli-responsive capsules are of interest in drug delivery, fragrance release, food preservation, and self-healing materials. Many methods are used to trigger the release of encapsulated contents. Here we highlight mechanisms for the controlled release of encapsulated cargo that utilize chemical reactions occurring in solid polymeric shell walls. Triggering mechanisms responsible for covalent bond cleavage that result in the release of capsule contents include chemical, biological, light, thermal, magnetic, and electrical stimuli. We present methods for encapsulation and release, triggering methods, and mechanisms and conclude with our opinions on interesting obstacles for chemically induced activation with relevance for controlled release.

First level trigger of the DIRAC experiment

International Nuclear Information System (INIS)

Afanas'ev, L.G.; Karpukhin, V.V.; Kulikov, A.V.; Gallas, M.

2001-01-01

The logic of the first level trigger of the DIRAC experiment at CERN is described. A parallel running of different trigger modes with tagging of events and optional independent prescaling is realized. A CAMAC-based trigger system is completely computer controlled

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.

Development of workflow planning software and a tracking study of the decay B+- --> J / Psi at the D0 Experiment

International Nuclear Information System (INIS)

Evans, David Edward

2003-01-01

A description of the development of the mc( ) runjob software package used to manage large scale computing tasks for the D0 Experiment at Fermilab is presented, along with a review of the Digital Front End Trigger electronics and the software used to control them. A tracking study is performed on detector data to determine that the D0 Experiment can detect charged B mesons, and that these results are in accordance with current results. B mesons are found by searching for the decay channel B ± → J/ψK ±

CMS Triggers for the LHC Startup

CERN Document Server

Nhan Nguyen, Chi

2009-01-01

The LHC will collide proton beams at a bunch-crossing rate of 40 MHz. At the design luminosity of $10^{34}$ cm$^{-2}$s$^{-1}$ each crossing results in an average of about 20 inelastic pp events. The CMS trigger system is designed to reduce the input rate to about 100 Hz. This task is carried out in two steps, namely the Level-1 (L1) and the High-Level trigger (HLT). The L1 trigger is built of customized fast electronics and is designed to reduce the rate to 100 kHz. The HLT is implemented in a filter farm running on hundreds of CPUs and is designed to reduce the rate by another factor of ~1000. It combines the traditional L2 and L3 trigger components in a novel way and allows the coherent tuning of the HLT algorithms to accommodate multiple physics channels. We will discuss the strategies for optimizing triggers covering the experiment`s early physics program.

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.

The Trigger for Early Running

CERN Document Server

The ATLAS Collaboration

2009-01-01

The ATLAS trigger and data acquisition system is based on three levels of event selection designed to capture the physics of interest with high efficiency from an initial bunch crossing rate of 40 MHz. The selections in the three trigger levels must provide sufficient rejection to reduce the rate to 200 Hz, compatible with offline computing power and storage capacity. The LHC is expected to begin its operation with a peak luminosity of 10^31 with a relatively small number of bunches, but quickly ramp up to higher luminosities by increasing the number of bunches, and thus the overall interaction rate. Decisions must be taken every 25 ns during normal LHC operations at the design luminosity of 10^34, where the average bunch crossing will contain more than 20 interactions. Hence, trigger selections must be deployed that can adapt to the changing beam conditions while preserving the interesting physics and satisfying varying detector requirements. In this paper, we provide a menu of trigger selections that can be...

BTeV detached vertex trigger

International Nuclear Information System (INIS)

Gottschalk, E.E.

2001-01-01

BTeV is a collider experiment that has been approved to run in the Tevatron at Fermilab. The experiment will conduct precision studies of CP violation using a forward-geometry detector. The detector will be optimized for high-rate detection of beauty and charm particles produced in collisions between protons and anti-protons. BTeV will trigger on beauty and charm events by taking advantage of the main difference between these heavy quark events and more typical hadronic events - the presence of detached beauty and charm decay vertices. The first stage of the BTeV trigger will receive data from a pixel vertex detector at a rate of 100 gb s -1 , reconstruct tracks and vertices for every beam crossing, reject 99% of beam crossings that do not produce beauty or charm particles, and trigger on beauty events with high efficiency. An overview of the trigger design and its influence on the design of the pixel vertex detector is presented

Convergent and Divergent Signaling in PAMP-Triggered Immunity and Effector-Triggered Immunity.

Science.gov (United States)

Peng, Yujun; van Wersch, Rowan; Zhang, Yuelin

2018-04-01

Plants use diverse immune receptors to sense pathogen attacks. Recognition of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors localized on the plasma membrane leads to PAMP-triggered immunity (PTI). Detection of pathogen effectors by intracellular or plasma membrane-localized immune receptors results in effector-triggered immunity (ETI). Despite the large variations in the magnitude and duration of immune responses triggered by different PAMPs or pathogen effectors during PTI and ETI, plasma membrane-localized immune receptors activate similar downstream molecular events such as mitogen-activated protein kinase activation, oxidative burst, ion influx, and increased biosynthesis of plant defense hormones, indicating that defense signals initiated at the plasma membrane converge at later points. On the other hand, activation of ETI by immune receptors localized to the nucleus appears to be more directly associated with transcriptional regulation of defense gene expression. Here, we review recent progress in signal transductions downstream of different groups of plant immune receptors, highlighting the converging and diverging molecular events.

The Trigger System of the CMS Experiment

OpenAIRE

Felcini, Marta

2008-01-01

We give an overview of the main features of the CMS trigger and data acquisition (DAQ) system. Then, we illustrate the strategies and trigger configurations (trigger tables) developed for the detector calibration and physics program of the CMS experiment, at start-up of LHC operations, as well as their possible evolution with increasing luminosity. Finally, we discuss the expected CPU time performance of the trigger algorithms and the CPU requirements for the event filter farm at start-up.