WorldWideScience

Sample records for physics experiment triggers

  1. 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

  2. Electronics, trigger, data acquisition, and computing working group on future B physics experiments

    International Nuclear Information System (INIS)

    Geer, S.

    1993-01-01

    Electronics, trigger, data acquisition, and computing: this is a very broad list of topics. Nevertheless in a modern particle physics experiment one thinks in terms of a data pipeline in which the front end electronics, the trigger and data acquisition, and the offline reconstruction are linked together. In designing any piece of this pipeline it is necessary to understand the bigger picture of the data flow, data rates and volume, and the input rate, output rate, and latencies for each part of the pipeline. All of this needs to be developed with a clear understanding of the requirements imposed by the physics goals of the experiment; the signal efficiencies, background rates, and the amount of recorded information that needs to be propagated through the pipeline to select and analyse the events of interest. The technology needed to meet the demanding high data volume needs of the next round of B physics experiments appears to be available, now or within a couple of years. This seems to be the case for both fixed target and collider B physics experiments. Although there are many differences between the various data pipelines that are being proposed, there are also striking similarities. All experiments have a multi-level trigger scheme (most have levels 1, 2, and 3) where the final level consists of a computing farm that can run offline-type code and reduce the data volume by a factor of a few. Finally, the ability to reconstruct large data volumes offline in a reasonably short time, and making large data volumes available to many physicists for analysis, imposes severe constraints on the foreseen data pipelines, and a significant uncertainty in evaluating the various approaches proposed

  3. Muon trigger, flavour tagging and physics performance of the LHCb experiment; Trigger a muons, etiquetage de la saveur et performances physiques de l'experience LHCb

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, O

    2007-10-15

    The LHCb experiment that is being settled in CERN is dedicated to the study of CP violation and rare decays in the field of beauty hadrons. The phenomenological background necessary to an adequate understanding of the physics of flavor is presented in the first chapter, it is shown how the flavordynamics can open the way to new physics. The second chapter is dedicated to a brief presentation of the LHCb detector. Two aspects of the design of the muon trigger are more detailed: the radiation resistance of the opto-electronic transmitters and the simulated performances of the trigger. The third chapter reviews the tasks linked to the tagging of the savors of B mesons which will be an important step in all the experiments made at LHCb. The recent progress in heavy savor physics as well as the expected contribution of LHCb in this field are presented in the fourth chapter, especially the search for new physics in penguin diagrams b {yields} s.

  4. 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.

  5. Triggering on New Physics with the CMS Detector

    Energy Technology Data Exchange (ETDEWEB)

    Bose, Tulika [Boston Univ., MA (United States)

    2016-07-29

    The BU CMS group led by PI Tulika Bose has made several significant contributions to the CMS trigger and to the analysis of the data collected by the CMS experiment. Group members have played a leading role in the optimization of trigger algorithms, the development of trigger menus, and the online operation of the CMS High-Level Trigger. The group’s data analysis projects have concentrated on a broad spectrum of topics that take full advantage of their strengths in jets and calorimetry, trigger, lepton identification as well as their considerable experience in hadron collider physics. Their publications cover several searches for new heavy gauge bosons, vector-like quarks as well as diboson resonances.

  6. Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

    Energy Technology Data Exchange (ETDEWEB)

    Aad, G.; Abat, E.; Abbott, B.; Abdallah, J.; Abdelalim, A.A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Acharya, Bobby Samir; Adams, D.L.; Addy, T.N.; Adorisio, C.; Adragna, P.; Adye, T.; Aguilar-Saavedra, J.A.; Aharrouche, M.; Ahlen, S.P.; Ahles, F.; Ahmad, A.; /SUNY, Albany /Alberta U. /Ankara U. /Annecy, LAPP /Argonne /Arizona U. /Texas U., Arlington /Athens U. /Natl. Tech. U., Athens /Baku, Inst. Phys. /Barcelona, IFAE /Belgrade U. /VINCA Inst. Nucl. Sci., Belgrade /Bergen U. /LBL, Berkeley /Humboldt U., Berlin /Bern U., LHEP /Birmingham U. /Bogazici U. /INFN, Bologna /Bologna U.

    2011-11-28

    the expression 'CSC studies' ('computing system commissioning'), which is occasionally referred to in these volumes. The work reported does generally assume that the detector is fully operational, and in this sense represents an idealised detector: establishing the best performance of the ATLAS detector with LHC proton-proton collisions is a challenging task for the future. The results summarised here therefore represent the best estimate of ATLAS capabilities before real operational experience of the full detector with beam. Unless otherwise stated, simulations also do not include the effect of additional interactions in the same or other bunch-crossings, and the effect of neutron background is neglected. Thus simulations correspond to the low-luminosity performance of the ATLAS detector. This report is broadly divided into two parts: firstly the performance for identification of physics objects is examined in detail, followed by a detailed assessment of the performance of the trigger system. This part is subdivided into chapters surveying the capabilities for charged particle tracking, each of electron/photon, muon and tau identification, jet and missing transverse energy reconstruction, b-tagging algorithms and performance, and finally the trigger system performance. In each chapter of the report, there is a further subdivision into shorter notes describing different aspects studied. The second major subdivision of the report addresses physics measurement capabilities, and new physics search sensitivities. Individual chapters in this part discuss ATLAS physics capabilities in Standard Model QCD and electroweak processes, in the top quark sector, in b-physics, in searches for Higgs bosons, supersymmetry searches, and finally searches for other new particles predicted in more exotic models.

  7. The multilevel trigger system of the DIRAC experiment

    International Nuclear Information System (INIS)

    Afanas'ev, L.; Gallas, M.; Goldin, D.

    2002-01-01

    The multilevel trigger system of the DIRAC experiment at CERN is presented. It includes a fast first level trigger as well as various trigger processors to select events with a pair of pions having a low relative momentum typical of the physical process under study. One of these processors employs the drift chamber data, another one is based on a neural network algorithm and the others use various hit-map detector correlations. Two versions of the trigger system used at different stages of the experiment are described. The complete system reduces the event rate by a factor of 1000, with efficiency ≥ 95 % of detecting the events in the relative momentum range of interest

  8. GPU-based real-time triggering in the NA62 experiment

    CERN Document Server

    Ammendola, R.; Cretaro, P.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P.S.; Pastorelli, E.; Piandani, R.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

    2016-01-01

    Over the last few years the GPGPU (General-Purpose computing on Graphics Processing Units) paradigm represented a remarkable development in the world of computing. Computing for High-Energy Physics is no exception: several works have demonstrated the effectiveness of the integration of GPU-based systems in high level trigger of different experiments. On the other hand the use of GPUs in the low level trigger systems, characterized by stringent real-time constraints, such as tight time budget and high throughput, poses several challenges. In this paper we focus on the low level trigger in the CERN NA62 experiment, investigating the use of real-time computing on GPUs in this synchronous system. Our approach aimed at harvesting the GPU computing power to build in real-time refined physics-related trigger primitives for the RICH detector, as the the knowledge of Cerenkov rings parameters allows to build stringent conditions for data selection at trigger level. Latencies of all components of the trigger chain have...

  9. Expected performance of the ATLAS experiment detector, trigger and physics

    CERN Document Server

    Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A.A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Acharya, Bobby Samir; Adams, D.L.; Addy, T.N.; Adorisio, C.; Adragna, P.; Adye, T.; Aguilar-Saavedra, J.A.; Aharrouche, M.; Ahlen, S.P.; Ahles, F.; Ahmad, A.; Ahmed, H.; Aielli, G.; Akdogan, T.; Akesson, T.P.A.; Akimoto, G.; Alam, M.S.; Alam, M.A.; Albert, J.; Albrand, S.; Aleksa, M.; Aleksandrov, I.N.; Alessandria, F.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Alimonti, G.; Alison, J.; Aliyev, M.; Allport, P.P.; Allwood-Spiers, S.E.; Aloisio, A.; Alon, R.; Alonso, A.; Alonso, J.; Alviggi, M.G.; Amako, K.; Amaral, P.; Amelung, C.; Ammosov, V.V.; Amorim, A.; Amoros, G.; Amram, N.; Anastopoulos, C.; Anders, C.F.; Anderson, K.J.; Andreazza, A.; Andrei, V.; Andrieux, M-L.; Anduaga, X.S.; Anghinolfi, F.; Antonaki, A.; Antonelli, M.; Antonelli, S.; Antunovic, B.; Anulli, F.A.; Arabidze, G.; Aracena, I.; Arai, Y.; Arce, A.T.H.; Archambault, J.P.; Arfaoui, S.; Arguin, J-F.; Argyropoulos, T.; Arik, E.; Arik, M.; Armbruster, A.J.; Arnaez, O.; Arnault, C.; Artamonov, A.; Arutinov, D.; Asai, M.; Asai, S.; Ask, S.; Asman, B.; Asner, D.; Asquith, L.; Assamagan, K.; Astbury, A.; Astvatsatourov, A.; Atkinson, T.; Atoian, G.; Auerbach, B.; Auge, E.; Augsten, K.; Aurousseau, M.A.; Austin, N.; Avolio, G.; Avramidou, R.; Axen, A.; Ay, C.; Azuelos, G.; Azuma, Y.; Baak, M.A.; Baccaglioni, G.; Bacci, C.; Bachacou, H.; Bachas, K.; Backes, M.; Badescu, E.; Bagnaia, P.; Bai, Y.; Bailey, D.C.; Baines, J.T.; Baker, O.K.; Baltasar Dos Santos Pedrosa, F.; Banas, E.; Banerjee, S.; Banfi, D.; Bangert, A.; Bansal, V.; Baranov, S.P.; Baranov, S.; Barashkou, A.; Barber, T.B.; Barberio, E.L.; Barberis, D.; Barbero, M.B.; Bardin, D.Y.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.B.; Barnett, B.M.; Barnett, R.M.; Baron, S.; Baroncelli, A.; Barr, A.J.; Barreiro, F.; Barreiro Guimaraes da Costa, J.; Barrillon, P.; Bartoldus, R.; Bartsch, D.; Bastos, J.; Bates, R.L.; Batley, J.R.; Battaglia, A.; Battistin, M.; Bauer, F.; Bazalova, M.; Beare, B.; Beauchemin, P.H.; Beccherle, R.B.; Becerici, N.; Bechtle, P.; Beck, G.A.; Beck, H.P.; Beckingham, M.; Becks, K.H.; Bedajanek, I.; Beddall, A.J.; Beddall, A.; Bednar, P.; Bednyakov, V.A.; Bee, C.; Behar Harpaz, S.; Behera, P.K.; Beimforde, M.; Belanger-Champagne, C.; Bell, P.J.; Bell, W.H.; Bella, G.; Bellagamba, L.; Bellina, F.; Bellomo, M.; Belloni, A.; Belotskiy, K.; Beltramello, O.; Ben Ami, S.; Benary, O.; Benchekroun, D.; Bendel, M.; Benedict, B.H.; Benekos, N.; Benhammou, Y.; Benincasa, G.P.; Benjamin, D.P.; Benoit, M.; Bensinger, J.R.; Benslama, K.; Bentvelsen, S.; Beretta, M.; Berge, D.; Bergeaas Kuutmann, Elin; Berger, N.; Berghaus, F.; Berglund, E.; Beringer, J.; Bernardet, K.; Bernat, P.; Bernhard, R.; Bernius, C.; Berry, T.; Bertin, A.; Besson, N.; Bethke, S.; Bianchi, R.M.; Bianco, M.; Biebel, O.; Biesiada, Jed; Biglietti, M.; Bilokon, H.; Binet, S.; Bingul, A.; Bini, C.; Biscarat, C.; Bischofberger, M.; Bitenc, U.; Black, K.M.; Blair, R.E.; Blanchot, G.; Blocker, C.; Blocki, J.; Blondel, A.; Blum, W.; Blumenschein, U.; Boaretto, C.; Bobbink, G.J.; Bocci, A.; Bodine, B.; Boek, J.; Boelaert, N.; Boeser, Sebastian; Bogaerts, J.A.; Bogouch, A.; Bohm, C.; Bohm, J.; Boisvert, V.; Bold, T.; Boldea, V.; Bondarenko, V.G.; Bondioli, M.; Boonekamp, M.; Booth, C.N.; Booth, P.S.L.; Booth, J.R.A.; Borisov, A.; Borissov, G.; Borjanovic, I.; Borroni, S.; Bos, K.; Boscherini, D.; Bosman, M.; Bosteels, M.; Boterenbrood, H.; Bouchami, J.; Boudreau, J.; Bouhova-Thacker, E.V.; Boulahouache, C.; Bourdarios, C.; Boyd, J.; Boyko, I.R.; Braem, A.; Branchini, P.; Brandenburg, G.W.; Brandt, A.; Brandt, O.; Bratzler, U.; Brau, J.E.; Braun, H.M.; Brelier, B.; Bremer, J.; Brenner, R.; Bressler, S.; Breton, D.; Brett, N.D.; Britton, D.; Brochu, F.M.; Brock, I.; Brock, R.; Brodet, E.; Broggi, F.; Brooijmans, G.; Brooks, W.K.; Brubaker, E.; Bruckman de Renstrom, P.A.; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Buanes, T.; Bucci, F.B.; Buchholz, P.; Buckley, A.G.; Budagov, I.A.; Buescher, Volker; Bugge, L.; Bujor, F.; Bulekov, O.; Bunse, M.; Buran, T.; Burckhart, H.; Burdin, S.; Burke, S.; Busato, E.; Buszello, C.P.; Butin, F.; Butler, B.; Butler, J.M.; Buttar, C.M.; Butterworth, J.M.; Byatt, T.; Cabrera Urban, S.; Caforio, D.; Cakir, O.; Calafiura, P.; Calderini, G.; Calkins, R.; Caloba, L.P.; Caloi, R.; Calvet, D.; Camarri, P.; Cambiaghi, M.; Cameron, D.; Campabadal Segura, F.; Campana, S.; Campanelli, M.; Canale, V.; Cantero, J.; Capeans Garrido, M.D.M.; Caprini, I.; Caprini, M.; Capua, M.; Caputo, R.; Caramarcu, C.; Cardarelli, R.; Carli, T.; Carlino, G.; Carminati, L.; Caron, B.; Caron, S.; Carron Montero, S.; Carter, A.A.; Carter, J.R.; Carvalho, J.; Casadei, D.; Casado, M.P.; Cascella, M.; Caso, C.; Castaneda Hernadez, A.M.; Castaneda Miranda, E.; Castillo Gimenez, V.; Castro, N.F.; Cataldi, G.; Catinaccio, A.; Catmore, J.R.; Cattai, A.; Cattani, G.; Caughron, S.; Cauz, D.; Cavalleri, P.; Cavalli, D.; Cavalli-Sforza, M.; Cavasinni, V.; Cazzato, A.; Ceradini, F.; Cerqueira, A.S.; Cerri, A.; Cerrito, L.; Cerutti, F.; Cetin, S.A.; Cevenini, F.; Chafaq, A.C.; Chakraborty, D.; Chapman, J.D.; Chapman, J.W.; Chareyre, E.C.; Charlton, D.G.; Chatterjii, S.C.; Cheatham, S.; Chekanov, S.; Chekulaev, S.V.; Chelkov, G.A.; Chen, H.; Chen, T.; Chen, X.; Cheng, S.; Cheng, T.L.; Cheplakov, A.; Chepurnov, V.F.; Cherkaoui El Moursli, R.; Tcherniatine, V.; Chesneanu, D.; Cheu, E.; Cheung, S.L.; Chevalier, L.; Chevallier, F.; Chiarella, V.; Chiefari, G.; Chikovani, L.; Childers, J.T.; Chilingarov, A.; Chiodini, G.; Chouridou, S.; Chren, D.; Christidi, I.A.; Christov, A.; Chromek-Burckhart, D.; Chu, M.L.; Chudoba, J.; Ciapetti, G.; Ciftci, A.K.; Ciftci, R.; Cindro, V.; Ciobotaru, M.D.; Ciocca, C.; Ciocio, A.; Cirilli, M.; Citterio, M.; Clark, A.; Cleland, W.; Clemens, J.C.; Clement, B.; Clement, C.; Clements, D.; Coadou, Y.; Cobal, M.; Coccaro, A.; Cochran, J.; Coelli, S.; Coggeshall, J.; Cogneras, E.; Cojocaru, C.D.; Colas, J.; Cole, B.; Colijn, A.P.; Collard, C.; Collins, N.J.; Collins-Tooth, C.; Collot, J.; Colon, G.; Coluccia, R.; Conde Muino, P.; Coniavitis, E.; Consonni, M.; Constantinescu, S.; Conta, C.; Conventi, F.; Cook, J.; Cooke, Mark S.; Cooper, B.D.; Cooper-Smith, N.J.; Copic, K.; Cornelissen, T.; Corradi, M.; Corriveau, F.C.; Corso-Radu, A.; Cortes-Gonzalez, A.; Costa, G.; Costa, M.J.; Costanzo, D.; Costin, T.; Cote, D.; Coura Torres, R.; Courneyea, L.; Cowan, G.; Cowden, C.C.; Cox, B.E.; Cranmer, K.; Cranshaw, J.; Cristinziani, M.; Crosetti, G.; Crupi, R.C.; Crepe-Renaudin, S.; Cuciuc, C.M.; Cuenca Almenar, C.; Curatolo, M.; Curtis, C.J.; Cwetanski, P.; Czyczula, Z.; D'Auria, S.; D'Onofrio, M.; D'Orazio, A.; Da Rocha Gesualdi Mello, A.; Da Silva, P.V.M.; Da Via, C.V.; Dabrowski, W.; Dai, T.; Dallapiccola, C.; Dallison, S.J.; Daly, C.H.; Dam, M.; Danielsson, H.O.; Dannheim, D.; Dao, V.; Darbo, G.; Davey, W.D.; Davidek, T.; Davidson, N.; Davidson, R.; Davison, A.R.; Dawson, I.; Dawson, J.W.; Daya, R.K.; De, K.; de Asmundis, R.; De Castro, S.; De Castro Faria Salgado, P.E.; De Cecco, S.; De Groot, N.; de Jong, P.; De La Cruz-Burelo, E.; De La Taille, C.; De Mora, L.; De Oliveira Branco, M.; De Pedis, D.; De Salvo, A.; De Sanctis, U.; De Santo, A.; De Vivie De Regie, J.B.; De Zorzi, G.; Dean, S.; Dedes, G.; Dedovich, D.V.; Defay, P.O.; Degenhardt, J.; Dehchar, M.; Del Papa, C.; Del Peso, J.; Del Prete, T.; Dell'Acqua, A.; Dell'Asta, L.; Della Pietra, M.; della Volpe, D.; Delmastro, M.; Delruelle, N.; Delsart, P.A.; Demers, S.; Demichev, M.; Demirkoz, B.; Deng, W.; Denisov, S.P.; Dennis, C.; Derue, F.; Dervan, P.; Desch, K.K.; Deviveiros, P.O.; Dewhurst, A.; Dhullipudi, R.; Di Ciaccio, A.; Di Ciaccio, L.; Di Domenico, A.; Di Girolamo, A.; Di Girolamo, B.; Di Luise, S.; Di Mattia, A.; Di Nardo, R.; Di Simone, A.; Di Sipio, R.; Diaz, M.A.; Diehl, E.B.; Dietrich, J.; Diglio, S.; Dindar Yagci, K.; Dingfelder, D.J.; Dionisi, C.; Dita, P.; Dita, S.; Dittus, F.; Djama, F.; Djilkibaev, R.; Djobava, T.; Vale, M.A.B.do; Dobbs, M.; Dobinson, R.; Dobos, D.; Dobson, E.; Dobson, M.; Dogan, O.B.; Doherty, T.; Doi, Y.; Dolejsi, J.; Dolenc, I.; Dolezal, Z.; Dolgoshein, B.A.; Donega, M.; Donini, J.; Donszelmann, T.; Dopke, J.; Dorfan, D.E.; Doria, A.; Dos Anjos, A.; Dosil, M.; Dotti, A.; Dova, M.T.; Doxiadis, A.; Doyle, A.T.; Dragic, J.D.; Drasal, Z.; Dressnandt, N.; Driouichi, C.; Dris, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Dudarev, A.; Duehrssen, M.; Duerdoth, I.P.; Duflot, L.; Dufour, M-A.; Dunford, M.; Duperrin, A.; Duran Yildiz, H.; Dushkin, A.; Duxfield, R.; Dwuznik, M.; Dueren, M.; Ebenstein, W.L.; Eckert, S.; Eckweiler, S.; Edmonds, K.; Eerola, P.; Egorov, K.; Ehrenfeld, W.; Ehrich, T.; Eifert, T.; Eigen, G.; Einsweiler, K.; Eisenhandler, E.; Ekelof, T.; El Kacimi, M.; Ellert, M.; Elles, S.; Ellis, K.; Ellis, N.; Elmsheuser, J.; Elsing, M.; Ely, R.; Emeliyanov, D.; Engelmann, R.; Engl, A.; Epp, B.; Eppig, A.; Epshteyn, V.S.; Erdmann, J.; Ereditato, A.; Eriksson, D.; Ermoline, I.; Ernst, J.; Ernst, E.; Ernwein, J.; Errede, D.; Errede, S.; Escalier, M.; Escobar, C.; Espinal Curull, X.; Esposito, B.; Etienne, F.; Etienvre, A.I.; Etzion, E.; Evans, H.; Fabbri, L.; Fabre, C.; Faccioli, P.; Facius, K.; Fakhrutdinov, R.M.; Falciano, S.; Falou, A.C.; Fang, Y.; Fanti, M.; Farbin, A.; Farilla, A.; Farley, J.; Farooque, T.; Farrington, S.M.; Farthouat, P.; Fassi, F.; Fassnacht, P.; Fassouliotis, D.; Fatholahzadeh, B.; Fayard, L.; Fayette, F.; Febbraro, R.; Federic, P.; Fedin, O.L.; Fedorko, I.; Feligioni, L.; Feng, C.; Feng, E.J.; Fenyuk, A.B.; Ferencei, J.; Ferland, J.; Fernando, W.; Ferrag, S.; Ferrari, A.; Ferrari, P.; Ferrari, R.; Ferrer, A.; Ferrer, M.L.; Ferrere, D.; Ferretti, C.; Fiascaris, M.; Fiedler, F.; Filipcic, A.; Filippas, A.; Filthaut, F.; Fincke-Keeler, M.; Fiorini, L.; Firan, A.; Fischer, G.; Fisher, M.J.; Flacher, H.F.; Flechl, M.; Fleck, I.; Fleckner, J.; Fleischmann, P.; Fleischmann, S.; Fleta Corral, C.M.; Flick, T.; Flores Castillo, L.R.; Flowerdew, M.J.; Foehlisch, F.; Fokitis, M.; Fonseca Martin, T.; Forbush, D.A.; Formica, A.; Forti, A.; Foster, J.M.; Fournier, D.; Foussat, A.; Fowler, A.J.; Fowler, K.F.; Fox, H.; Francavilla, P.; Franchino, S.; Francis, D.; Franz, S.; Fraternali, M.; Fratina, S.; Freestone, J.; Froeschl, R.; Froidevaux, D.; Frost, J.A.; Fukunaga, C.; Fullana Torregrosa, E.; Fuster, J.; Gabaldon, C.; Gabizon, O.G.; Gadfort, T.; Gadomski, S.; Gagliardi, G.; Gagnon, P.; Gallas, E.J.; Gallas, M.V.; Gallop, B.J.; Galyaev, E.; Gan, K.K.; Gao, Y.S.; Gaponenko, A.; Garcia-Sciveres, M.; Garcia, C.; Garcia Navarro, J.E.; Gardner, R.W.; Garelli, N.; Garitaonandia, H.; Garonne, V.G.; Gatti, C.; Gaudio, G.; Gaumer, O.; Gauzzi, P.; Gavrilenko, I.L.; Gay, C.; Gaycken, G.G.; Gayde, J-C.; Gazis, E.N.; Gee, C.N.P.; Geich-Gimbel, Ch.; Gellerstedt, K.; Gemme, C.; Genest, M.H.; Gentile, S.; Georgatos, F.; George, S.; Gerlach, P.; Geweniger, C.; Ghazlane, H.; Ghez, P.; Ghodbane, N.; Giacobbe, B.; Giagu, S.; Giangiobbe, V.; Gianotti, F.; Gibbard, B.; Gibson, A.; Gibson, S.M.; Gilbert, L.M.; Gilchriese, M.; Gilewsky, V.; Gillman, A.R.; Gingrich, D.M.; Ginzburg, J.; Giokaris, N.; Giordani, M.P.; Giovannini, P.; Giraud, P.F.; Girtler, P.; Giugni, D.; Giusti, P.; Gjelsten, B.K.; Gladilin, L.K.; Glasman, C.; Glazov, A.; Glitza, K.W.; Glonti, G.L.; Gnanvo, K.G.; Godfrey, J.G.; Godlewski, J.; Goepfert, T.; Goessling, C.; Goettfert, T.; Goggi, V.G.; Goldfarb, S.; Goldin, D.; Golling, T.; Gollub, N.P.; Gomes, A.; Goncalo, R.; Gong, C.; Gonzalez de la Hoz, S.; Gonzalez Silva, M.L.; Gonzalez-Sevilla, S.; Goodson, J.J.; Goossens, L.; Gorbounov, P.A.; Gordon, H.; Gorelov, I.; Gorfine, G.; Gorini, B.; Gorini, E.; Gorisek, A.; Gornicki, E.; Gorokhov, S.A.; Goryachev, S.V.; Goryachev, V.N.; Gosdzik, B.; Gosselink, M.; Gostkin, M.I.; Gough Eschrich, I.; Gouighri, M.; Goujdami, D.; Goulette, M.; Goussiou, A.G.; Gowdy, S.; Goy, C.; Grabowska-Bold, I.; Grafstroem, P.; Grahn, K-J.; Granado Cardoso, L.; Grancagnolo, F.; Grancagnolo, S.; Gratchev, V.; Gray, H.M.; Gray, J.A.; Graziani, E.; Green, B.; Greenwood, Z.D.; Gregor, I.M.; Griesmayer, E.; Grigalashvili, N.; Grillo, A.A.; Grimm, K.; Grishkevich, Y.V.; Groer, L.S.; Grognuz, J.; Groh, M.; Groll, M.; Gross, E.; Grosse-Knetter, J.; Groth-Jensen, J.; Gruse, C.; Grybel, K.; Guarino, V.J.; Guicheney, C.; Guida, A.G.; Guillemin, T.; Gunther, J.; Guo, B.; Gupta, A.; Gusakov, Y.; Gutierrez, P.; Guttman, N.G.; Gutzwiller, O.; Guyot, C.; Gwenlan, C.; Gwilliam, C.B.; Haas, A.; Haas, S.; Haber, C.; Hackenburg, R.; Hadavand, H.K.; Hadley, D.R.; Haertel, R.; Hajduk, Z.; Hakobyan, H.; Hakobyan, R.H.; Haller, J.; Hamacher, K.; Hamilton, A.; Han, H.; Han, L.; Hanagaki, K.; Hance, M.; Handel, C.; Hanke, P.; Hansen, J.R.; Hansen, J.B.; Hansen, J.D.; Hansen, P.H.; Hansl-Kozanecka, T.; Hansson, P.; Hara, K.; Hare, G.A.; Harenberg, T.; Harrington, R.D.; Harris, O.B.; Harris, O.M.; Hart, J.C.; Hartert, J.; Hartjes, F.; Haruyama, T.; 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Read, A.L.; Rebuzzi, D.M.; Redlinger, G.R.; Reece, R.; Reeves, K.; Reinherz-Aronis, E.; Reisinger, I.; Reljic, D.; Rembser, C.; Ren, Z.; Renkel, P.; Rescia, S.; Rescigno, M.; Resconi, S.; Resende, B.; Rezaie, E.; Reznicek, P.; Richards, A.; Richards, R.A.; Richter, R.; Richter-Was, E.; Ridel, M.; Rieke, S.; Rijpstra, M.; Rijssenbeek, M.; Rimoldi, A.; Rios, R.R.; Risler, C.; Riu, I.; Rivoltella, G.; Rizatdinova, F.; Roberts, K.; Robertson, S.H.; Robichaud-Veronneau, A.; Robinson, D.; Robson, A.; Rocha de Lima, J.G.; Roda, C.; Rodriguez, D.; Rodriguez, Y.; Roe, S.; Rohne, O.; Rojo, V.; Rolli, S.; Romaniouk, A.; Romanov, V.M.; Romeo, G.; Romero, D.; Roos, L.; Ros, E.; Rosati, S.; Rosenbaum, G.A.; Rosenberg, E.I.; Rosselet, L.; Rossi, L.P.; Rotaru, M.; Rothberg, J.; Rottlaender, I.; Rousseau, D.; Royon, C.R.; Rozanov, A.; Rozen, Y.; Ruckert, B.; Ruckstuhl, N.; Rud, V.I.; Rudolph, G.; Ruehr, F.; Ruggieri, F.; Ruiz-Martinez, A.; Rumiantsev, V.; Rumyantsev, L.; Rusakovich, N.A.; Rust, D.R.; Rutherfoord, J.P.; Ruwiedel, C.; Ruzicka, P.; Ryabov, Y.F.; Ryadovikov, V.; Ryan, P.; Rybin, A.M.; Rybkin, G.; Rzaeva, S.; Saavedra, A.F.; Sadrozinski, H.F-W.; Sadykov, R.; Sakamoto, H.; Salamanna, G.; Salamon, A.; Saleem, M.; Salihagic, D.; Salnikov, A.; Salt, J.; Salvachua Ferrando, B.M.; Salvatore, D.; Salvatore, F.; Salzburger, A.; Sampsonidis, D.; Samset, B.H.; Sanchis Lozano, M.A.; Sandaker, H.; Sander, H.G.; Sandhoff, M.; Sandvoss, S.; Sankey, D.P.C.; Sanny, B.; Sansoni, A.; Santamarina Rios, C.; Santi, L.; Santoni, C.; Santonico, R.; Santos, D.; Saraiva, J.G.; Sarangi, T.; Sarri, F.; Sasaki, O.; Sasaki, T.; Sasao, N.; Satsounkevitch, I.; Sauvage, G.; Savard, P.; Savine, A.Y.; Savinov, V.; Sawyer, L.; Saxon, D.H.; Says, L.P.; Sbarra, C.; Sbrizzi, A.; Scannicchio, D.A.; Schaarschmidt, J.; Schacht, P.; Schaefer, U.; Schaetzel, S.; Schaffer, A.C.; Schaile, D.; Schamberger, R.; Schamov, A.G.; Schegelsky, V.A.; Schernau, M.; Scherzer, M.I.; Schiavi, C.; Schieck, J.; Schioppa, M.; Schlenker, S.; Schlereth, J.L.; Schmid, P.; Schmidt, M.P.; Schmitt, C.; Schmitz, M.; Schott, M.; Schouten, D.; Schovancova, J.; Schram, M.; Schreiner, A.; Schroers, M.S.; Schuh, S.; Schuler, G.; Schultes, J.; Schultz-Coulon, H-C.; Schumacher, J.; Schumacher, M.; Schumm, B.S.; Schune, Ph.; Schwanenberger, C.S.; Schwartzman, A.; Schwemling, Ph.; Schwienhorst, R.; Schwierz, R.; Schwindling, J.; Scott, W.G.; Sedykh, E.; Segura, E.; Seidel, S.C.; Seiden, A.; Seifert, F.S.; Seixas, J.M.; Sekhniaidze, G.; Seliverstov, D.M.; Sellden, B.; Seman, M.; Semprini-Cesari, N.; Serfon, C.; Serin, L.; Seuster, R.; Severini, H.; Sevior, M.E.; Sfyrla, A.; Shan, L.; Shank, J.T.; Shapiro, M.; Shatalov, P.B.; Shaver, L.; Shaw, C.; Shaw, K.S.; Sherman, D.; Sherwood, P.; Shibata, A.; Shimojima, M.; Shin, T.; Shmeleva, A.; Shochet, M.J.; Shupe, M.A.; Sicho, P.; Sidoti, A.; Siebel, A.; Siebel, M.; Siegrist, J.; Sijacki, D.; Silbert, O.; Silva, J.; Silverstein, S.B.; Simak, V.; Simic, Lj.; Simion, S.; Simmons, B.; Simonyan, M.; Sinervo, P.; Sipica, V.; Siragusa, G.; Sisakyan, A.N.; Sivoklokov, S.Yu.; Sjolin, J.; Skubic, P.; Skvorodnev, N.; Slavicek, T.; Sliwa, K.; Sloper, J.; Sluka, T.; Smakhtin, V.; Smirnov, S.Yu.; Smirnov, Y.; Smirnova, L.N.; Smirnova, O.; Smith, B.C.; Smith, K.M.; Smizanska, M.; Smolek, K.; Snesarev, A.A.; Snow, S.W.; Snow, J.; Snuverink, J.; Snyder, S.; Soares, M.; Sobie, R.; Sodomka, J.; Soffer, A.; Solans, C.A.; Solar, M.; Solfaroli Camillocci, E.; Solodkov, A.A.; Solovyanov, O.V.; Soluk, R.; Sondericker, J.; Sopko, V.; Sopko, B.; Sosebee, M.; Sosnovtsev, V.V.; Sospedra Suay, L.; Soukharev, A.; Spagnolo, S.; Spano, F.; Speckmayer, P.; Spencer, E.; Spighi, R.; Spigo, G.; Spila, F.; Spiwoks, R.; Spogli, L.; Spousta, M.; Spreitzer, T.; Spurlock, B.; St. Denis, R.D.; Stahl, T.; Stamen, R.; Stancu, S.N.; Stanecka, E.; Stanek, R.W.; Stanescu, C.; Stapnes, S.; Starchenko, E.A.; Stark, J.; Staroba, P.; Stastny, J.; Staude, A.; Stavina, P.; Stavropoulos, G.; Steinbach, P.; Steinberg, P.; Stekl, I.; Stelzer, H.J.; Stenzel, H.; Stevenson, K.S.; Stewart, G.; Stewart, T.D.; Stockton, M.C.; Stoicea, G.; Stonjek, S.; Strachota, P.; Stradling, A.; Straessner, A.; Strandberg, J.; Strandberg, S.; Strandlie, A.; Strauss, M.; Strizenec, P.; Strohmer, R.; Strom, D.M.; Strong, J.A.; Stroynowski, R.; Stugu, B.; Stumer, I.; Su, D.; Subramania, S.; Suchkov, S.I.; Sugaya, Y.; Sugimoto, T.; Suhr, C.; Suk, M.; Sulin, V.V.; Sultansoy, S.; Sundermann, J.E.; Suruliz, K.; Sushkov, S.; Susinno, G.; Sutton, M.R.; Suzuki, T.; Sviridov, Yu.M.; Sykora, I.; Sykora, T.; Szczygiel, R.R.; Szymocha, T.; Sanchez, J.; Ta, D.; Taffard, A.T.; Tafirout, R.; Taga, A.; Takahashi, Y.; Takai, H.; Takashima, R.; Takeda, H.; Takeshita, T.; Talby, M.; Tali, B.; Talyshev, A.; Tamsett, M.C.; Tanaka, J.; Tanaka, R.; Tanaka, S.; Tappern, G.P.; Tapprogge, S.; Tarem, S.; Tarrade, F.; Tartarelli, G.F.; Tas, P.; Tasevsky, M.; Tassi, E.T.; Taylor, C.; Taylor, F.E.; Taylor, G.N.; Taylor, R.P.; Taylor, W.; Tegenfeldt, F.; Teixeira-Dias, P.; Ten Kate, H.; Teng, P.K.; Terada, S.; Terashi, K.; Terron, J.; Terwort, M.; Teuscher, R.J.; Tevlin, C.M.; Thadome, J.; Thananuwong, R.; Thioye, M.; Thomas, J.P.; Thomas, T.L.; Thompson, E.N.; Thompson, P.D.; Thompson, R.J.; Thompson, A.S.; Thomson, E.; Thun, R.P.; Tic, T.; Tikhomirov, V.O.; Tikhonov, Y.A.; Timmermans, C.J.W.P.; Tipton, P.; Tique Aires Viegas, F.J.; Tisserant, S.; Tobias, J.; Toczek, B.; Todorov, T.T.; Todorova-Nova, S.; Tojo, J.; Tokar, S.; Tokushuku, K.; Tomasek, L.; Tomasek, M.; Tomasz, F.; Tomoto, M.; Tompkins, D.; Tompkins, L.; Toms, K.; Tonazzo, A.; Tong, G.; Tonoyan, A.; Topfel, C.; Topilin, N.D.; Torrence, E.; Torro Pastor, E.; Toth, J.; Touchard, F.; Tovey, D.R.; Tovey, S.N.; Trefzger, T.; Tremblet, L.; Tricoli, A.; Trigger, I.M.; Trincaz-Duvoid, S.; Tripiana, M.F.; Triplett, N.; Trischuk, W.; Trivedi, A.; Trocme, B.; Troncon, C.; Tsarouchas, C.; Tseng, J.C-L.; Tsiafis, I.; Tsiakiris, M.; Tsiareshka, P.V.; Tsipolitis, G.; Tskhadadze, E.G.; Tsukerman, I.I.; Tsulaia, V.; Tsuno, S.; Turala, M.; Turecek, D.; Turk Cakir, I.; Turlay, E.; Tuts, P.M.; Twomey, M.S.; Tyndel, M.; Typaldos, D.; Tzanakos, G.; Ueda, I.; Uhrmacher, M.; Ukegawa, F.; Unal, G.; Underwood, D.G.; Undrus, A.; Unel, G.; Unno, Y.; Urkovsky, E.; Urquijo, P.; Urrejola, P.; Usai, G.; Vacavant, L.; Vacek, V.; Vachon, B.; Vahsen, S.; Valderanis, C.; Valenta, J.; Valente, P.; Valkar, S.; Valls Ferrer, J.A.; Van der Bij, H.; van der Graaf, H.; van der Kraaij, E.; van der Poel, E.; van Eldik, N.; van Gemmeren, P.; van Kesteren, Z.; van Vulpen, I.; VanBerg, R.; Vandelli, W.; Vandoni, G.; Vaniachine, A.; Vankov, P.; Vannucci, F.; Varela Rodriguez, F.; Vari, R.; Varnes, E.W.; Varouchas, D.; Vartapetian, A.; Varvell, K.E.; Vassilakopoulos, V.I.; Vassilieva, L.; Vataga, E.; Vazeille, F.; Vegni, G.; Veillet, J.J.; Vellidis, C.; Veloso, F.; Veness, R.; Veneziano, S.; Ventura, Andrea; Ventura, D.; Ventura, S.; Venturi, N.; Vercesi, V.; Verducci, M.; Verkerke, W.; Vermeulen, J.C.; Vetterli, M.C.; Vichou, I.; Vickey, T.; Viehhauser, G.H.A.; Villa, M.; Villani, E.G.; Villaplana Perez, M.; Vilucchi, E.; Vincter, M.G.; Vinogradov, V.B.; Virchaux, M.; Viret, S.; Virzi, J.; Vitale, A.; Vitells, O.V.; Vivarelli, I.; Vives, R.; Vives Vaques, F.; Vlachos, S.; Vlasak, M.; Vlasov, N.; Vogt, H.; Vokac, P.; Volpi, M.; Volpini, G.; von der Schmitt, H.; von Loeben, J.; von Toerne, E.; Vorobel, V.; Vorobiev, A.P.; Vorwerk, V.; Vos, M.; Voss, R.; Voss, T.T.; Vossebeld, J.H.; Vranjes, N.; Vrba, V.; Vreeswijk, M.; Vu Anh, T.; Vudragovic, M.; Vuillermet, R.; Vukotic, I.; Wagner, P.; Wahlen, H.; Walbersloh, J.; Walder, J.; Walker, R.; Walkowiak, W.; Wall, R.; Wang, C.; Wang, J.; Wang, J.C.; Wang, S.M.W.; Ward, C.P.; Warsinsky, M.; Watkins, P.M.; Watson, A.T.; Watts, G.; Watts, S.W.; Waugh, A.T.; Waugh, B.M.; Webel, M.; Weber, J.; Weber, M.; Weber, M.S.; Weber, P.; Weidberg, A.R.; Weingarten, J.; Weiser, C.; Wellenstein, H.; Wells, P.S.; Wen, M.; Wenaus, T.; Wendler, S.; Wengler, T.; Wenig, S.; Wermes, N.; Werner, M.; Werner, P.; Werthenbach, U.; Wessels, M.; Wheeler-Ellis, S.J.; Whitaker, S.P.; White, A.; White, M.J.; White, S.; Whiteson, D.; Whittington, D.; Wicek, F.; Wicke, D.; Wickens, F.J.; Wiedenmann, W.; Wielers, M.; Wienemann, P.; Wiglesworth, C.; Wildauer, A.; Wildt, M.A.; Wilhelm, I.; Wilkens, H.G.; Williams, H.H.; Willis, W.; Willocq, S.; Wilson, J.A.; Wilson, M.G.; Wilson, A.; Wingerter-Seez, I.; Winklmeier, F.W.; Winton, L.; Wittgen, M.; Wolter, M.W.; Wolters, H.; Wosiek, B.; Wotschack, J.; Woudstra, M.J.; Wraight, K.; Wright, C.; Wrona, B.; Wu, S.L.; Wu, X.; Xella, S.; Xie, S.; Xie, Y.; Xu, G.; Xu, N.; Yamamoto, A.; Yamamoto, S.; Yamamura, T.; Yamanaka, K.; Yamazaki, T.; Yamazaki, Y.; Yan, Z.; Yang, H.; Yang, U.K.; Yang, Y.; Yang, Z.; Yao, W-M.; Yao, Y.; Yasu, Y.; Ye, J.; Ye, S.; Yilmaz, M.; Yoosoofmiya, R.; Yorita, K.; Yoshida, R.; Young, C.; Youssef, S.P.; Yu, D.; Yu, J.; Yu, M.; Yu, X.; Yuan, J.; Yuan, L.; Yurkewicz, A.; Zaidan, R.; Zaitsev, A.M.; Zajacova, Z.; Zanello, L.; Zarzhitsky, P.; Zaytsev, A.; Zdrazil, M.; Zeitnitz, C.; Zeller, M.; Zema, P.F.; Zendler, C.; Zenin, A.V.; Zenis, T.; Zenonos, Z.; Zenz, S.; Zerwas, D.; Zhan, Z.; Zhang, H.; Zhang, J.; Zhang, Q.; Zheng, W.; Zhang, X.; Zhao, L.; Zhao, T.; Zhao, Z.; Zhelezko, A.; Zhemchugov, A.; Zheng, S.; Zhong, J.; Zhou, B.; Zhou, N.; Zhou, S.; Zhou, Y.; Zhu, C.G.; Zhu, H.; Zhu, Y.; Zhuang, X.A.; Zhuravlov, V.; Zilka, B.; Zimmermann, R.; Zimmermann, S.; Zinna, M.; Ziolkowski, M.; Zitoun, R.; Zivkovic, L.; Zmouchko, V.V.; Zobernig, G.; Zoccoli, A.; zur Nedden, M.; Zychacek, V.

    2009-01-01

    A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.

  10. A high-voltage triggered pseudospark discharge experiment

    International Nuclear Information System (INIS)

    Ramaswamy, K.; Destler, W.W.; Rodgers, J.

    1996-01-01

    The design and execution of a pulsed high-voltage (350 endash 400 keV) triggered pseudospark discharge experiment is reported. Experimental studies were carried out to obtain an optimal design for stable and reliable pseudospark operation in a high-voltage regime (approx-gt 350 kV). Experiments were performed to determine the most suitable fill gas for electron-beam formation. The pseudospark discharge is initiated by a trigger mechanism involving a flashover between the trigger electrode and hollow cathode housing. Experimental results characterizing the electron-beam energy using the range-energy method are reported. Source size imaging was carried out using an x-ray pinhole camera and a novel technique using Mylar as a witness plate. It was experimentally determined that strong pinching occurred later in time and was associated with the lower-energy electrons. copyright 1996 American Institute of Physics

  11. 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

  12. SSC physics signatures and trigger requirements

    International Nuclear Information System (INIS)

    1985-01-01

    Strategies are considered for triggering on new physics processes on the environment of the SSC, where interaction rates will be very high and most new physics processes quite rare. The quantities available for use in the trigger at various levels are related to the signatures of possible new physics. Two examples were investigated in some detail using the ISAJET Monte Carlo program: Higgs decays to W pairs and a missing energy trigger applied to gluino pair production. In both of the examples studied in detail, it was found that workable strategies for reducing the trigger rate were obtainable which also produced acceptable efficiency for the processes of interest. In future work, it will be necessary to carry out such a program for the full spectrum of suggested new physics

  13. 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

  14. The new Global Muon Trigger of the CMS experiment

    CERN Document Server

    Fulcher, Jonathan Richard; Rabady, Dinyar Sebastian; Reis, Thomas; Sakulin, Hannes

    2016-01-01

    For the 2016 physics data runs the L1 trigger system of the Compact Muon Solenoid (CMS) experiment underwent a major upgrade to cope with the increasing instantaneous luminosity of the CERN LHC whilst maintaining a high event selection efficiency for the CMS physics program. Most subsystem specific trigger processor boards were replaced with powerful general purpose processor boards, conforming to the MicroTCA standard, whose tasks are performed by firmware on an FPGA of the Xilinx Virtex 7 family. Furthermore, the muon trigger system moved from a subsystem centered approach, where each of the three muon detector systems provides muon candidates to the Global Muon Trigger (GMT), to a region based system, where muon track finders (TFs) combine information from the subsystems to generate muon candidates in three detector regions, that are then sent to the upgraded GMT. The upgraded GMT receives up to 108 muons from the processors of the muon TFs in the barrel, overlap, and endcap detector regions. The muons are...

  15. Level Zero Trigger Processor for the NA62 experiment

    Science.gov (United States)

    Soldi, D.; Chiozzi, S.

    2018-05-01

    The NA62 experiment is designed to measure the ultra-rare decay K+ arrow π+ ν bar nu branching ratio with a precision of ~ 10% at the CERN Super Proton Synchrotron (SPS). The trigger system of NA62 consists in three different levels designed to select events of physics interest in a high beam rate environment. The L0 Trigger Processor (L0TP) is the lowest level system of the trigger chain. It is hardware implemented using programmable logic. The architecture of the NA62 L0TP system is a new approach compared to existing systems used in high-energy physics experiments. It is fully digital, based on a standard gigabit Ethernet communication between detectors and the L0TP Board. The L0TP Board is a commercial development board, mounting a programmable logic device (FPGA). The primitives generated by sub-detectors are sent asynchronously using the UDP protocol to the L0TP during the entire beam spill period. The L0TP realigns in time the primitives coming from seven different sources and performs a data selection based on the characteristics of the event such as energy, multiplicity and topology of hits in the sub-detectors. It guarantees a maximum latency of 1 ms. The maximum input rate is about 10 MHz for each sub-detector, while the design maximum output trigger rate is 1 MHz. A description of the trigger algorithm is presented here.

  16. Full-scale physical model of landslide triggering

    Science.gov (United States)

    Lora, M.; Camporese, M.; Salandin, P.

    2013-12-01

    Landslide triggering induced by high-intensity rainfall infiltration in hillslopes is a complex phenomenon that involves hydrological processes operating at different spatio-temporal scales. Empirical methods give rough information about landslide-prone areas, without investigating the theoretical framework needed to achieve an in-depth understanding of the involved physical processes. In this study, we tackle this issue through physical experiments developed in an artificial hillslope realized in the Department of Civil, Environmental and Architectural Engineering of the University of Padua. The structure consists of a reinforced concrete box containing a soil prism with the following maximum dimensions: 3.5 m high, 6 m long, and 2 m wide. In order to analyze and examine the triggered failure state, the experiments are carried out with intensive monitoring of pore water pressure and moisture content response. Subsurface monitoring instruments are installed at several locations and depths to measure downward infiltration and/or a rising groundwater table. We measure the unsaturated soil water pressure as well as positive pore pressures preceding failure in each experiments with six tensiometers. The volumetric water content is determined through six Time Domain Reflectometry probes. Two pressure transducers are located in observation wells to determine the position of the water table in time. Two stream gauges are positioned at the toeslope, for measuring both runoff and subsurface outflow. All data are collected and recorded by an acquisition data system from Campbell Scientific. The artificial hillslope is characterized by well-known and controlled conditions, which are designed to reproduce an ideal set-up susceptible to heavy rainfall landslide. The hydrologic forcing is generated by a rainfall simulator realized with nozzles from Sprying System and. specifically designed to produce a spatially uniform rainfall of intensity ranging from 50 to 150 mm/h. The aim

  17. 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

  18. Experience with the custom-developed ATLAS Offline Trigger Monitoring Framework and Reprocessing Infrastructure

    CERN Document Server

    Bartsch, V

    2012-01-01

    After about two years of data taking with the ATLAS detector manifold experience with the custom-developed trigger monitoring and reprocessing infrastructure could be collected. The trigger monitoring can be roughly divided into online and offline monitoring. The online monitoring calculates and displays all rates at every level of the trigger and evaluates up to 3000 data quality histograms. The physics analysis relevant data quality information is being checked and recorded automatically. The offline trigger monitoring provides information depending of the physics motivated different trigger streams after a run has finished. Experts are checking the information being guided by the assessment of algorithms checking the current histograms with a reference. The experts are recording their assessment in a so-called data quality defects which are used to select data for physics analysis. In the first half of 2011 about three percent of all data had an intolerable defect resulting from the ATLAS trigger system. T...

  19. Towards a Level-1 Tracking Trigger for the ATLAS Experiment

    CERN Document Server

    De Santo, A; The ATLAS collaboration

    2014-01-01

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

  20. Tracking in the trigger from the CDF experience to CMS upgrade

    CERN Document Server

    Palla, F

    2007-01-01

    Precise tracking information in the online selection of interesting physics events is extremely beneficial at hadron colliders. The CDF experiment at the Tevatron, has shown for the first time the impact of the tracking in triggers, allowing to achieve unprecedented precision in B-physics measurements. The CMS experiment at LHC will largely make use of tracking information at high level trigger, after the Level-1 acceptance. The increased luminosity of the Super-LHC collider will impose to CMS a drastic revision of the Level-1 trigger strategy, incorporating the tracker information at the first stage of the selection. After a review of the CDF and CMS approaches we will discuss several possible Level-1 tracker based concepts for the upgraded CMS detector at Super-LHC. One approach is based on associative memories, which has already been demonstrated in CDF. It makes use of binary readout in the front end electronics, followed by transfer of the full granularity data off detector using optical links to dedicat...

  1. GPU Enhancement of the Trigger to Extend Physics Reach at the LHC

    CERN Document Server

    Halyo, V; Jindal, P; LeGresley, P; Lujan, P

    2013-01-01

    Significant new challenges are continuously confronting the High Energy Physics (HEP) experiments, in particular the two detectors at the Large Hadron Collider (LHC) at CERN, where nominal conditions deliver proton-proton collisions to the detectors at a rate of 40 MHz. This rate must be significantly reduced to comply with both the performance limitations of the mass storage hardware and the capabilities of the computing resources to process the collected data in a timely fashion for physics analysis. At the same time, the physics signals of interest must be retained with high efficiency. The quest for rare new physics phenomena at the LHC leads us to evaluate a Graphics Processing Unit (GPU) enhancement of the existing High-Level Trigger (HLT), made possible by the current flexibility of the trigger system, which not only provides faster and more efficient event selection, but also includes the possibility of new complex triggers that were not previously feasible. A new tracking algorithm is evaluated on a ...

  2. Smart Trigger Pre-Processor Custom Electronics for the PHENIX Experiment

    International Nuclear Information System (INIS)

    Nagle, James L.

    2003-01-01

    OAK-B135 The document provides a final technical report on activities and accomplishments of the experimental relativistic heavy ion physics group at the University of Colorado at Boulder as supported by the Outstanding Junior Investigator Program, Division of Nuclear Physics at the Department of Energy. All of the goals of the grant proposal were achieved during this last year of the Outstanding Junior Investigator funding period. The development of a Smart Trigger Pre-Processor module for fast trigger primitive calculations in the PHENIX experiment has been completed. We finalized the board design, constructed and tested two prototype modules, and with additional funding from the PHENIX project, we fabricated a full set of 15 modules for the Muon Tracking system. During Run-4 at RHIC:, we have begun the process of integrating these modules into the PHENIX data acquisition system, Additionally, we put a large Effort into developing new trigger and fast-track analysis methods for J j J data filtering and reconstruction. These algorithms make use of the trigger primitivE∼s generated via the new electronics

  3. Towards a Level-1 tracking trigger for the ATLAS experiment

    CERN Document Server

    Cerri, A; The ATLAS collaboration

    2014-01-01

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

  4. arXiv Level Zero Trigger Processor for the NA62 experiment

    CERN Document Server

    INSPIRE-00584493; Chiozzi, Stefano

    2018-05-02

    The NA62 experiment is designed to measure the ultra-rare decay K+ arrow π+ ν  branching ratio with a precision of ~ 10% at the CERN Super Proton Synchrotron (SPS). The trigger system of NA62 consists in three different levels designed to select events of physics interest in a high beam rate environment. The L0 Trigger Processor (L0TP) is the lowest level system of the trigger chain. It is hardware implemented using programmable logic. The architecture of the NA62 L0TP system is a new approach compared to existing systems used in high-energy physics experiments. It is fully digital, based on a standard gigabit Ethernet communication between detectors and the L0TP Board. The L0TP Board is a commercial development board, mounting a programmable logic device (FPGA). The primitives generated by sub-detectors are sent asynchronously using the UDP protocol to the L0TP during the entire beam spill period. The L0TP realigns in time the primitives coming from seven different sources and performs a data selectio...

  5. 2017 B-Physics trigger efficiencies

    CERN Document Server

    CMS Collaboration

    2018-01-01

    The performance of the trigger used to select B-Physics decay channels in CMS is presented for data collected in 2017, corresponding to an integrated luminosity of $9.8\\,\\mathrm{fb}^{-1}$ at $13\\,\\mathrm{TeV}$.

  6. 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.

  7. 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...

  8. 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...

  9. 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

  10. A Track Reconstructing Low-latency Trigger Processor for High-energy Physics

    CERN Document Server

    AUTHOR|(CDS)2067518

    2009-01-01

    The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 µs to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbps via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's dr...

  11. 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.

  12. Upgrade of the Global Muon Trigger for the Compact Muon Solenoid experiment at CERN

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00356020; Widmann, Eberhard

    The Large Hadron Collider is a large particle accelerator at the CERN research laboratory, designed to provide particle physics experiments with collisions at unprecedented centre-of-mass energies. For its second running period both the number of colliding particles and their collision energy were increased. To cope with these more challenging conditions and maintain the excellent performance seen during the first running period, the Level-1 trigger of the Compact Muon Solenoid experiment --- a sophisticated electronics system designed to filter events in real-time --- was upgraded. This upgrade consisted of the complete replacement of the trigger electronics and a full redesign of the system's architecture. While the calorimeter trigger path now follows a time-multiplexed processing model where the entire trigger data for a collision are received by a single processing board, the muon trigger path was split into regional track finding systems where each newly introduced track finder receives data from all th...

  13. A track reconstructing low-latency trigger processor for high-energy physics

    International Nuclear Information System (INIS)

    Cuveland, Jan de

    2009-01-01

    The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 μs to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbit/s via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's drift chambers based on explicit value comparisons, calculates the momentum of the originating particles from the course of the reconstructed tracks, and finally leads to a trigger decision. The architecture is capable of processing up to 20 000 track segments in less than 2 μs with high detection efficiency and reconstruction precision for high-momentum particles. As a result, this thesis shows how a trigger processor performing complex online track reconstruction within tight real-time requirements can be realized. The presented hardware has been built and is in continuous data taking operation in the ALICE experiment. (orig.)

  14. A track reconstructing low-latency trigger processor for high-energy physics

    Energy Technology Data Exchange (ETDEWEB)

    Cuveland, Jan de

    2009-09-17

    The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 {mu}s to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbit/s via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's drift chambers based on explicit value comparisons, calculates the momentum of the originating particles from the course of the reconstructed tracks, and finally leads to a trigger decision. The architecture is capable of processing up to 20 000 track segments in less than 2 {mu}s with high detection efficiency and reconstruction precision for high-momentum particles. As a result, this thesis shows how a trigger processor performing complex online track reconstruction within tight real-time requirements can be realized. The presented hardware has been built and is in continuous data taking operation in the ALICE experiment. (orig.)

  15. 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...

  16. 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

  17. 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...

  18. Relating triggering processes in lab experiments with earthquakes.

    Science.gov (United States)

    Baro Urbea, J.; Davidsen, J.; Kwiatek, G.; Charalampidou, E. M.; Goebel, T.; Stanchits, S. A.; Vives, E.; Dresen, G.

    2016-12-01

    Statistical relations such as Gutenberg-Richter's, Omori-Utsu's and the productivity of aftershocks were first observed in seismology, but are also common to other physical phenomena exhibiting avalanche dynamics such as solar flares, rock fracture, structural phase transitions and even stock market transactions. All these examples exhibit spatio-temporal correlations that can be explained as triggering processes: Instead of being activated as a response to external driving or fluctuations, some events are consequence of previous activity. Although different plausible explanations have been suggested in each system, the ubiquity of such statistical laws remains unknown. However, the case of rock fracture may exhibit a physical connection with seismology. It has been suggested that some features of seismology have a microscopic origin and are reproducible over a vast range of scales. This hypothesis has motivated mechanical experiments to generate artificial catalogues of earthquakes at a laboratory scale -so called labquakes- and under controlled conditions. Microscopic fractures in lab tests release elastic waves that are recorded as ultrasonic (kHz-MHz) acoustic emission (AE) events by means of piezoelectric transducers. Here, we analyse the statistics of labquakes recorded during the failure of small samples of natural rocks and artificial porous materials under different controlled compression regimes. Temporal and spatio-temporal correlations are identified in certain cases. Specifically, we distinguish between the background and triggered events, revealing some differences in the statistical properties. We fit the data to statistical models of seismicity. As a particular case, we explore the branching process approach simplified in the Epidemic Type Aftershock Sequence (ETAS) model. We evaluate the empirical spatio-temporal kernel of the model and investigate the physical origins of triggering. Our analysis of the focal mechanisms implies that the occurrence

  19. Real time physics analysis with the ATLAS tau trigger system

    International Nuclear Information System (INIS)

    Casado Lechuga, M. P.

    2009-01-01

    The scope of the ATLAS tau trigger system at the LHC is most ambitious. It aims at reconstructing in real time, a matter of seconds, a detailed picture of the high energy proton proton collisions at the LHC. Such system is mandatory in order to select efficiently data needed for discovery of new physics in a proton proton collision environment where the rates of jets observed in the detector are high and the tau identification is difficult. New physics scenarios targeted specifically by the the ATLAS tau trigger system are Standard Model or Supersymmetric Higgs production, and production of new exotic resonances. This contribution will detail how the analysis techniques developed offline for efficient data analysis have been implemented in the algorithms which run online at the trigger. In particular, the focus will be on how to satisfy the requirements imposed by the physics goals while addressing the limitations from the overall event rate and latency allowed. The prospects for early running during the first LHC collisions and trigger evolution from first collisions to stable running will be also summarized, following change of trigger goals from commissioning of detector to measurement of Standard Model physics and discoveries. (author)

  20. The second level trigger of the L3 experiment. Pt. 1

    International Nuclear Information System (INIS)

    Bertsch, Y.; Blaising, J.J.; Bonnefon, H.; Chollet-Leflour, F.; Degre, A.; Dromby, G.; Lecoq, J.; Morand, R.; Moynot, M.; Perrot, G.; Riccadonna, X.

    1994-01-01

    The second level trigger of the L3 experiment performs online background rejection and reduces the first level trigger rate to a value fitting with the third level trigger processing capability. Designed around a set of three bit-slice XOP microprocessors, it can process up to 500 first level triggers per second without significant dead time in the data acquisition. At each LEP beam crossing (45/90 kHz) the complete trigger information (5 kbytes) is memorized in a 1.4 gigabyte bandwidth real dual port memory. The XOP processor builds up the trigger block in less than 400 μs, and signs the background or physics origin of the current event in less than 3 ms. These very high performances rely essentially on the association of parallelism with high speed ECL technology, provided by dedicated processors fully integrated in Fastbus. Emphasis is given here to the specific hardware developed, to its operation and technical aspects of its installation and integration. The system described here ensures the L3 data taking since the beginning of LEP in July 1989 and the online rejection since 1990. (orig.)

  1. 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...

  2. 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...

  3. 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

  4. Upgrade of the global muon trigger at the CMS experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00282545; Sakulin, Hannes

    2016-09-14

    The Compact Muon Solenoid (CMS) experiment is one of two general purpose detectors at the Large Hadron Collider (LHC) at the particle physics research laboratory in Geneva (CERN). As such it allows a broad array of physics analyses from precision measurements of the standard model of particle physics to searches for exotic new particles. A series of upgrades and maintenance procedures took place in the first shut down from 2013 to 2015. The aim was to prepare the LHC for the collision energy of 13 TeV and further increase its luminosity. During this shut down also upgrades of the CMS experiment were installed.Due to the high rate of collisions at the LHC, it is impossible to record all such events. In order to reduce the event rate to a manageable level, a trigger system is deployed that selects interesting events. At the CMS experiment this system is divided into two levels: A first hardware based system that is optimised for speed and a second that is software based and applies more time consuming and preci...

  5. From the physical model to the electronic system - OMTF Trigger for CMS

    CERN Document Server

    Bluj, Michael; Byszuk, Adrian; Doroba, Krzysztof; Drabik, Pawel; Górski, Maciej; Kalinowski, A; Kierzkowski, Krzysztof; Konecki, Marcin; Miętki, Pawel; Okliński, Wojciech; Olszewski, Michal; Poźniak, Krzysztof; Zabołotny, Wojiech M; Zawistowski, Krystian; Żarnecki, Grzegorz

    2016-01-01

    The paper presents the development of the Overlap Muon Track Finder (OMTF) trigger for the CMS experiment at CERN. The transition from the data produced by the physical model to the algorithm suitable for practical implementation is shown. The paper also concentrates on the problems related to the necessity of continuous adaptation of the algorithm to the changing operating conditions of the detector

  6. UCTM2: An updated User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Bourrion, O., E-mail: olivier.bourrion@lpsc.in2p3.fr; Boyer, B.; Derome, L.; Pignol, G.

    2016-06-11

    We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

  7. Electronic trigger for the ASP experiment

    International Nuclear Information System (INIS)

    Wilson, R.J.

    1985-11-01

    The Anomalous Single Photon (ASP) electronic trigger is described. The experiments is based on an electromagnetic calorimeter composed of arrays of lead glass blocks, read out with photo-multiplier tubes, surrounding the interaction point at the PEP storage ring. The primary requirement of the trigger system is to be sensitive to low energy (approx. =0.5 GeV and above) photons whilst discriminating against high backgrounds at PEP. Analogue summing of the PMT signals and a sequence of programmable digital look-up tables produces a ''dead-timeless'' trigger for the beam collision rate of 408 kHz. 6 refs., 6 figs

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. First Operational Experience with the LHC Beam Dump Trigger Synchronisation Unit

    CERN Document Server

    Antoine, A; Magnin, N; Juteau, P; Voumard, N

    2011-01-01

    Two LHC Beam Dumping Systems (LBDS) remove the counter-rotating beams safely from the collider during setting up of the accelerator, at the end of a physics run and in case of emergencies. Dump requests can come from 3 different sources: the machine protection system in emergency cases, the machine timing system for scheduled dumps or the LBDS itself in case of internal failures. These dump requests are synchronized with the 3 μs beam abort gap in a fail-safe redundant Trigger Synchronization Unit (TSU) based on a Digital Phase Locked Loop (DPLL), locked onto the LHC beam revolution frequency with a maximum phase error of 40 ns. The synchronized trigger pulses coming out of the TSU are then distributed to the high voltage generators of the beam dump kickers through a redundant fault-tolerant trigger distribution system. This paper describes the operational experience gained with the TSU since its commissioning with beam in 2009, and highlights the improvements, which have been implemented f...

  15. Sum-Trigger-II status and prospective physics

    Energy Technology Data Exchange (ETDEWEB)

    Dazzi, Francesco; Mirzoyan, Razmik; Schweizer, Thomas; Teshima, Masahiro [Max Planck Institut fuer Physik, Munich (Germany); Herranz, Diego; Lopez, Marcos [Universidad Complutense, Madrid (Spain); Mariotti, Mose [Universita degli Studi di Padova (Italy); Nakajima, Daisuke [The University of Tokio (Japan); Rodriguez Garcia, Jezabel [Max Planck Institut fuer Physik, Munich (Germany); Instituto Astrofisico de Canarias, Tenerife (Spain)

    2015-07-01

    MAGIC is a stereoscopic system of 2 Imaging Air Cherenkov Telescopes (IACTs) for very high energy gamma-ray astronomy, located at La Palma (Spain). Lowering the energy threshold of IACTs is crucial for the observation of Pulsars, high redshift AGNs and GRBs. A novel trigger strategy, based on the analogue sum of a patch of pixels, can lead to a lower threshold compared to conventional digital triggers. In the last years, a major upgrade of the MAGIC telescopes took place in order to optimize the performances, mainly in the low energy domain. The PMTs camera and the reflective surface of MAGIC-I, as well as both readout systems, have been deeply renovated. The last important milestone is the implementation of a new stereoscopic analogue trigger, dubbed Sum-Trigger-II. The installation successfully ended in 2014 and the first data set has been already taken. Currently the fine-tuning of the main parameters as well as the comparison with Monte Carlo studies is ongoing. In this talk the status of Sum-Trigger-II and the future prospective physics cases at very low energy are presented.

  16. Does heavy physical exertion trigger myocardial infarction?

    DEFF Research Database (Denmark)

    Hallqvist, J; Möller, J; Ahlbom, A

    2000-01-01

    To study possible triggering of first events of acute myocardial infarction by heavy physical exertion, the authors conducted a case-crossover analysis (1993-1994) within a population-based case-referent study in Stockholm County, Sweden (the Stockholm Heart Epidemiology Program). Interviews were...

  17. Improving the ATLAS physics potential with the Fast Track Trigger System

    CERN Document Server

    Cavaliere, Viviana; The ATLAS collaboration

    2015-01-01

    The ATLAS Fast TracKer (FTK) is a custom electronics system that will operate at the full Level-1 accept rate, 100 kHz, to provide high quality tracks as input to the High-Level Trigger. The event reconstruction is performed in hardware, thanks to the massive parallelism of associative memories (AM) and FPGAs. We present the advantages for the physics goals of the ATLAS experiment and the recent results on the design, technological advancements and testing of some of the core components used in the processor.

  18. 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...

  19. Time-stamping system for nuclear physics experiments at RIKEN RIBF

    International Nuclear Information System (INIS)

    Baba, H.; Ichihara, T.; Ohnishi, T.; Takeuchi, S.; Yoshida, K.; Watanabe, Y.; Ota, S.; Shimoura, S.; Yoshinaga, K.

    2015-01-01

    A time-stamping system for nuclear physics experiments has been introduced at the RIKEN Radioactive Isotope Beam Factory. Individual trigger signals can be applied for separate data acquisition (DAQ) systems. After the measurements are complete, separately taken data are merged based on the time-stamp information. In a typical experiment, coincidence trigger signals are formed from multiple detectors to take desired events only. The time-stamping system allows the use of minimum bias triggers. Since coincidence conditions are given by software, a variety of physics events can be flexibly identified. The live time for a DAQ system is important when attempting to determine reaction cross-sections. However, the combined live time for separate DAQ systems is not clearly known because it depends not only on the DAQ dead time but also on the coincidence conditions. Using the proposed time-stamping system, all trigger timings can be acquired, so that the combined live time can be easily determined. The combined live time is also estimated using Monte Carlo simulations, and the results are compared with the directly measured values in order to assess the accuracy of the simulation

  20. 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.

  1. The Jefferson Lab Trigger Supervisor System

    International Nuclear Information System (INIS)

    Ed Jastrzembsi; David Abbott; Graham Heyes; R.W. MacLeod; Carl Timmer; Elliott Wolin

    2000-01-01

    We discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. We also discuss the enhanced features of a new Trigger Supervisor Module now under construction

  2. Towards a Level-1 Tracking Trigger for the ATLAS Experiment

    CERN Document Server

    De Santo, A; The ATLAS collaboration

    2016-01-01

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

  3. The Jefferson Lab Trigger Supervisor System

    International Nuclear Information System (INIS)

    Jastrzembski, E.; Abbott, D.J.; Heyes, W.G.; MacLeod, R.W.; Timmer, C.; Wolin, E.

    1999-01-01

    The authors discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. They also discuss the enhanced features of a new Trigger Supervisor Module now under construction

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Triggered fragmentation experiment with sodium, silicone oil and pentane

    International Nuclear Information System (INIS)

    Morita, T.

    1990-12-01

    Within the analysis of severe hypothetical fast breeder accidents the consequences of a fuel-coolant-interaction have to be considered, i.e. the thermal interaction between hot molten fuel and sodium. For the detailed understanding of the fragmentation during the thermal interaction of a hot liquid droplet with a cold fluid series of experiments were performed with sodium and solicone oil as hot liquid and pentane as cold easily volatile fluid. For the precise observation of the reaction an efficient high speed camera with a maximum recording frequency of 1x105 f/s was used. So the fragmentation caused by boiling phenomena could be observed. The pictures were used to estimate quantitatively e.g. the volume of the reaction zone and its expansion rate. By a special measuring device for the first time results on the time dependent portion of the liquid within the reaction zone could be gained. Based on the measured results of the experiments the course of a typical reaction, which can be devided into six phases, is presented and physically explained in this report. The influence of experimental parameters, as pressure of the external trigger and temperature of the hot liquid droplet, was investigated and from this the role of the homogeneous nucleation temperature and the external trigger for the reaction was deduced. (orig.) [de

  9. 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.

  10. Workshop on data acquisition and trigger system simulations for high energy physics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-31

    This report discusses the following topics: DAQSIM: A data acquisition system simulation tool; Front end and DCC Simulations for the SDC Straw Tube System; Simulation of Non-Blocklng Data Acquisition Architectures; Simulation Studies of the SDC Data Collection Chip; Correlation Studies of the Data Collection Circuit & The Design of a Queue for this Circuit; Fast Data Compression & Transmission from a Silicon Strip Wafer; Simulation of SCI Protocols in Modsim; Visual Design with vVHDL; Stochastic Simulation of Asynchronous Buffers; SDC Trigger Simulations; Trigger Rates, DAQ & Online Processing at the SSC; Planned Enhancements to MODSEM II & SIMOBJECT -- an Overview -- R.; DAGAR -- A synthesis system; Proposed Silicon Compiler for Physics Applications; Timed -- LOTOS in a PROLOG Environment: an Algebraic language for Simulation; Modeling and Simulation of an Event Builder for High Energy Physics Data Acquisition Systems; A Verilog Simulation for the CDF DAQ; Simulation to Design with Verilog; The DZero Data Acquisition System: Model and Measurements; DZero Trigger Level 1.5 Modeling; Strategies Optimizing Data Load in the DZero Triggers; Simulation of the DZero Level 2 Data Acquisition System; A Fast Method for Calculating DZero Level 1 Jet Trigger Properties and Physics Input to DAQ Studies.

  11. Workshop on data acquisition and trigger system simulations for high energy physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses the following topics: DAQSIM: A data acquisition system simulation tool; Front end and DCC Simulations for the SDC Straw Tube System; Simulation of Non-Blocklng Data Acquisition Architectures; Simulation Studies of the SDC Data Collection Chip; Correlation Studies of the Data Collection Circuit ampersand The Design of a Queue for this Circuit; Fast Data Compression ampersand Transmission from a Silicon Strip Wafer; Simulation of SCI Protocols in Modsim; Visual Design with vVHDL; Stochastic Simulation of Asynchronous Buffers; SDC Trigger Simulations; Trigger Rates, DAQ ampersand Online Processing at the SSC; Planned Enhancements to MODSEM II ampersand SIMOBJECT -- an Overview -- R.; DAGAR -- A synthesis system; Proposed Silicon Compiler for Physics Applications; Timed -- LOTOS in a PROLOG Environment: an Algebraic language for Simulation; Modeling and Simulation of an Event Builder for High Energy Physics Data Acquisition Systems; A Verilog Simulation for the CDF DAQ; Simulation to Design with Verilog; The DZero Data Acquisition System: Model and Measurements; DZero Trigger Level 1.5 Modeling; Strategies Optimizing Data Load in the DZero Triggers; Simulation of the DZero Level 2 Data Acquisition System; A Fast Method for Calculating DZero Level 1 Jet Trigger Properties and Physics Input to DAQ Studies

  12. The CDF silicon vertex trigger for B-mesons physics study

    International Nuclear Information System (INIS)

    Belforte, S.; Donati, S.; Ristori, L.; Spinella, F.; Budagov, Yu.; Chlachidze, G.; Glagolev, V.; Semenov, A.; Sisakyan, A.; Punzi, G.

    2001-01-01

    The CDF scientific program includes particularly the study of some key topics of the Standard Model: 1) constraint of the CKM matrix: CP violation in B sector (B 0 → π + π - ) and B s mixing (B s 0 → D s - π + , B s 0 → D s - π + π - π + ); 2) t-quark physics (t → Wb); and processes beyond the Standard Model - e.g., Higgs searching (MSSM) in the H → b bar b mode. All the above processes have the common feature - the presence of b-quarks (B-mesons). B hadrons of sufficiently high transverse momentum are characterized by a large mean value of distribution of the impact parameter with respect to the beam axis. That means events containing this kind of particles can be recognized and separated from non-long-lived background simply by cutting on the track's impact parameter. The upgraded CDF is equipped by the so-called Silicon Vertex Tracker (SVT), a unique electronic device for real time track reconstruction using the data from two CDF track detectors: the silicon strip vertex detector and drift chamber. The SVT is a level-2 trigger which within 10 μs reconstructs the tracks and obtains the transverse momentum (p t ), azimuthal angle (φ) and impact parameter (d) with 30 μm precision. The simulation studies show the background reduction by factor 1000 for B 0 π + π - by demand d > 100 μm for at least two tracks. This trigger is the first one of this sort ever used for hadron collider experiments: it enables to trigger on the secondary vertex, which opens the unique new opportunities in the heavy quark physics study. The basic logic, architecture and perspectives of SVT application are briefly described

  13. GPUs for the realtime low-level trigger of the NA62 experiment at CERN

    CERN Document Server

    Ammendola, R; Biagioni, A; Chiozzi, S; Cotta Ramusino, A; Fantechi, R; Fiorini, M; Gianoli, A; Graverini, E; Lamanna, G; Lonardo, A; Messina, A; Neri, I; Pantaleo, F; Paolucci, P S; Piandani, R; Pontisso, L; Simula, F; Sozzi, M; Vicini, P

    2015-01-01

    A pilot project for the use of GPUs (Graphics processing units) in online triggering ap- plications for high energy physics experiments (HEP) is presented. GPUs offer a highly parallel architecture and the fact that most of the chip resources are devoted to computa- tion. Moreover, they allow to achieve a large computing power using a limited amount of space and power. The application of online parallel computing on GPUs is shown for the synchronous low level trigger of NA62 experiment at CERN. Direct GPU communication using a FPGA-based board has been exploited to reduce the data transmission latency and results on a first field test at CERN will be highlighted. This work is part of a wider project named GAP (GPU application project), intended to study the use of GPUs in real-time applications in both HEP and medical imagin

  14. 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.

  15. Recycled memories : can flashbacks be triggered through experience design?

    OpenAIRE

    Fridriksson, Fridrik Steinn

    2013-01-01

    This paper examines the phenomenon flashbacks, often named the Proust phenomenon, through the lens of experience design. The research question is Can flashbacks be triggered through experience design? It would then be possible to call flashbacks memories recycled memories. To answer the question former studies were researched, mainly from the standpoint of cognitive psychology. The thesis discusses how different senses produce flashbacks and how they can be used as triggers. The difference be...

  16. Sub-nanosecond clock synchronization and trigger management in the nuclear physics experiment AGATA

    International Nuclear Information System (INIS)

    Bellato, M; Isocrate, R; Rampazzo, G; Bazzacco, D; Bortolato, D; Triossi, A; Chavas, J; Mengoni, D; Recchia, F

    2013-01-01

    The new-generation spectrometer AGATA, the Advanced GAmma Tracking Array, requires sub-nanosecond clock synchronization among readout and front-end electronics modules that may lie hundred meters apart. We call GTS (Global Trigger and Synchronization System) the infrastructure responsible for precise clock synchronization and for the trigger management of AGATA. It is made of a central trigger processor and nodes, connected in a tree structure by means of optical fibers operated at 2Gb/s. The GTS tree handles the synchronization and the trigger data flow, whereas the trigger processor analyses and eventually validates the trigger primitives centrally. Sub-nanosecond synchronization is achieved by measuring two different types of round-trip times and by automatically correcting for phase-shift differences. For a tree of depth two, the peak-to-peak clock jitter at each leaf is 70 ps; the mean phase difference is 180 ps, while the standard deviation over such phase difference, namely the phase equalization repeatability, is 20 ps. The GTS system has run flawlessly for the two-year long AGATA campaign, held at the INFN Legnaro National Laboratories, Italy, where five triple clusters of the AGATA sub-array were coupled with a variety of ancillary detectors

  17. Sub-nanosecond clock synchronization and trigger management in the nuclear physics experiment AGATA

    Science.gov (United States)

    Bellato, M.; Bortolato, D.; Chavas, J.; Isocrate, R.; Rampazzo, G.; Triossi, A.; Bazzacco, D.; Mengoni, D.; Recchia, F.

    2013-07-01

    The new-generation spectrometer AGATA, the Advanced GAmma Tracking Array, requires sub-nanosecond clock synchronization among readout and front-end electronics modules that may lie hundred meters apart. We call GTS (Global Trigger and Synchronization System) the infrastructure responsible for precise clock synchronization and for the trigger management of AGATA. It is made of a central trigger processor and nodes, connected in a tree structure by means of optical fibers operated at 2Gb/s. The GTS tree handles the synchronization and the trigger data flow, whereas the trigger processor analyses and eventually validates the trigger primitives centrally. Sub-nanosecond synchronization is achieved by measuring two different types of round-trip times and by automatically correcting for phase-shift differences. For a tree of depth two, the peak-to-peak clock jitter at each leaf is 70 ps; the mean phase difference is 180 ps, while the standard deviation over such phase difference, namely the phase equalization repeatability, is 20 ps. The GTS system has run flawlessly for the two-year long AGATA campaign, held at the INFN Legnaro National Laboratories, Italy, where five triple clusters of the AGATA sub-array were coupled with a variety of ancillary detectors.

  18. 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.

  19. The Evolution of the Trigger and Data Acquisition System in the ATLAS Experiment

    CERN Document Server

    Garelli, N; 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 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. \

  20. FPGA-based fast pipeline-parameterized-sorter implementation for first level trigger systems in HEP experiments

    CERN Document Server

    Pozniak, Krzysztof T

    2004-01-01

    The paper describes a behavioral model of fast, pipeline sorter dedicated to electronic triggering applications in the experiments of high energy physics (HEP). The sorter was implemented in FPGA for the RPC Muon Detector of CMS experiment (LHC accelerator, CERN) and for Backing Calorimeter (BAC) in ZEUS experiment (HERA accelerator, DESY) . A general principle of the applied sorting algorithm was presented. The implementation results were debated in detail for chosen FPGA chips by ALTERA and XILINX manufactures. The realization costs have been calculated as function of system parameters.

  1. Microprocessors in physics experiments at SLAC

    International Nuclear Information System (INIS)

    Rochester, L.S.

    1981-01-01

    The increasing size and complexity of high energy physics experiments is changing the way data are collected. To implement a trigger or event filter requires complex logic which may have to be modified as the experiment proceeds. Simply to monitor a detector, large amounts of data must be processed online. The use of microprocessors or other programmable devices can help to achieve these ends flexibly and economically. At SLAC, a number of microprocessor-based systems have been built and are in use in experimental setups, and others are now being developed. This talk is a review of existing systems and their use in experiments, and of developments in progress and future plans. (orig.)

  2. Microprocessors in physics experiments at SLAC

    International Nuclear Information System (INIS)

    Rochester, L.S.

    1981-04-01

    The increasing size and complexity of high energy physics experiments is changing the way data are collected. To implement a trigger or event filter requires complex logic which may have to be modified as the experiment proceeds. Simply to monitor a detector, large amounts of data must be processed on line. The use of microprocessors or other programmable devices can help to achieve these ends flexibly and economically. At SLAC, a number of microprocessor-based systems have been built and are in use in experimental setups, and others are now being developed. This talk is a review of existing systems and their use in experiments, and of developments in progress and future plans

  3. The ATLAS Tau Trigger

    CERN Document Server

    Rados, PK; The ATLAS collaboration

    2014-01-01

    Physics processes involving tau leptons play a crucial role in understanding particle physics at the high energy frontier. The ability to efficiently trigger on events containing hadronic tau decays is therefore of particular importance to the ATLAS experiment. During the 2012 run, the Large Hadronic Collder (LHC) reached instantaneous luminosities of nearly $10^{34} cm^{-2}s^{-1}$ with bunch crossings occurring every $50 ns$. This resulted in a huge event rate and a high probability of overlapping interactions per bunch crossing (pile-up). With this in mind it was necessary to design an ATLAS tau trigger system that could reduce the event rate to a manageable level, while efficiently extracting the most interesting physics events in a pile-up robust manner. In this poster the ATLAS tau trigger is described, its performance during 2012 is presented, and the outlook for the LHC Run II is briefly summarized.

  4. 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

  5. A proposed Drift Tubes-seeded muon track trigger for the CMS experiment at the High Luminosity-LHC

    CERN Document Server

    AUTHOR|(CDS)2070813; Lazzizzera, Ignazio; Vanini, Sara; Zotto, Pierluigi

    2016-01-01

    The LHC program at 13 and 14 TeV, after the observation of the candidate SM Higgs boson, will help clarify future subjects of study and shape the needed tools. Any upgrade of the LHC experiments for unprecedented luminosities, such as the High Luminosity-LHC ones, must then maintain the acceptance on electroweak processes that can lead to a detailed study of the properties of the candidate Higgs boson. The acceptance of the key lepton, photon and hadron triggers should be kept such that the overall physics acceptance, in particular for low-mass scale processes, can be the same as the one the experiments featured in 2012.In such a scenario, a new approach to early trigger implementation is needed. One of the major steps will be the inclusion of high-granularity tracking sub-detectors, such as the CMS Silicon Tracker, in taking the early trigger decision. This contribution can be crucial in several tasks, including the confirmation of triggers in other subsystems, and the improvement of the on-line momentum mea...

  6. 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.

  7. BTeV trigger/DAQ innovations

    International Nuclear Information System (INIS)

    Votava, Margaret

    2005-01-01

    The BTeV experiment was a collider based high energy physics (HEP) B-physics experiment proposed at Fermilab. It included a large-scale, high speed trigger/data acquisition (DAQ) system, reading data off the detector at 500 Gbytes/sec and writing to mass storage at 200 Mbytes/sec. The online design was considered to be highly credible in terms of technical feasibility, schedule and cost. This paper will give an overview of the overall trigger/DAQ architecture, highlight some of the challenges, and describe the BTeV approach to solving some of the technical challenges. At the time of termination in early 2005, the experiment had just passed its baseline review. Although not fully implemented, many of the architecture choices, design, and prototype work for the online system (both trigger and DAQ) were well on their way to completion. Other large, high-speed online systems may have interest in the some of the design choices and directions of BTeV, including (a) a commodity-based tracking trigger running asynchronously at full rate, (b) the hierarchical control and fault tolerance in a large real time environment, (c) a partitioning model that supports offline processing on the online farms during idle periods with plans for dynamic load balancing, and (d) an independent parallel highway architecture

  8. The Level 0 Trigger Processor for the NA62 experiment

    International Nuclear Information System (INIS)

    Chiozzi, S.; Gamberini, E.; Gianoli, A.; Mila, G.; Neri, I.; Petrucci, F.; Soldi, D.

    2016-01-01

    In the NA62 experiment at CERN, the intense flux of particles requires a high-performance trigger for the data acquisition system. A Level 0 Trigger Processor (L0TP) was realized, performing the event selection based on trigger primitives coming from sub-detectors and reducing the trigger rate from 10 to 1 MHz. The L0TP is based on a commercial FPGA device and has been implemented in two different solutions. The performance of the two systems are highlighted and compared.

  9. The Level 0 Trigger Processor for the NA62 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Chiozzi, S. [INFN, Ferrara (Italy); Gamberini, E. [University of Ferrara and INFN, Ferrara (Italy); Gianoli, A. [INFN, Ferrara (Italy); Mila, G. [University of Turin and INFN, Turin (Italy); Neri, I., E-mail: neri@fe.infn.it [University of Ferrara and INFN, Ferrara (Italy); Petrucci, F. [University of Ferrara and INFN, Ferrara (Italy); Soldi, D. [University of Turin and INFN, Turin (Italy)

    2016-07-11

    In the NA62 experiment at CERN, the intense flux of particles requires a high-performance trigger for the data acquisition system. A Level 0 Trigger Processor (L0TP) was realized, performing the event selection based on trigger primitives coming from sub-detectors and reducing the trigger rate from 10 to 1 MHz. The L0TP is based on a commercial FPGA device and has been implemented in two different solutions. The performance of the two systems are highlighted and compared.

  10. Triggering, front-end electronics, and data acquisition for high-rate beauty experiments

    International Nuclear Information System (INIS)

    Johnson, M.; Lankford, A.J.

    1988-04-01

    The working group explored the feasibility of building a trigger and an electronics data acquisition system for both collider and fixed target experiments. There appears to be no fundamental technical limitation arising from either the rate or the amount of data for a collider experiment. The fixed target experiments will likely require a much higher rate because of the smaller cross section. Rates up to one event per RF bucket (50 MHz) appear to be feasible. Higher rates depend on the details of the particular experiment and trigger. Several ideas were presented on multiplicity jump and impact parameter triggers for fixed target experiments. 14 refs., 3 figs

  11. The ATLAS Trigger Menu design for higher luminosities in Run 2

    CERN Document Server

    Torro Pastor, Emma; The ATLAS collaboration

    2018-01-01

    The ATLAS experiment aims at recording about 1 kHz of physics collisions, starting with an LHC design bunch crossing rate of 40 MHz. To reduce the large background rate while maintaining a high selection efficiency for rare physics events (such as beyond the Standard Model physics), a two-level trigger system is used. Events are selected based on physics signatures such as the presence of energetic leptons, photons, jets or large missing energy. The trigger system exploits topological information, as well as multivariate methods to carry out the necessary physics filtering for the many analyses that are pursued by the ATLAS community. In total, the ATLAS online selection consists of nearly two thousand individual triggers. A Trigger Menu is the compilation of these triggers, it specifies the physics selection algorithms to be used during data taking and the rate and bandwidth a given trigger is allocated. Trigger menus must reflect the physics goals of the collaboration for a given run, but also take into con...

  12. Physics at the CERN collider using a ''minimum bias'' trigger

    International Nuclear Information System (INIS)

    Arnison, G.; Astbury, A.; Grayer, G.; Haynes, W.J.; Nandi, A.K.; Roberts, C.; Scott, W.; Shah, T.P.; Bezaguet, A.; Boeck, R.; Calvetti, M.; Carroll, T.; Cennini, P.; Centro, S.; Ceradini, F.; Cittolin, S.; Demoulin, M.; DiBitinto, D.; Ellis, N.; Hoffmann, H.; Jank, W.; Jorat, G.; Kowalski, H.; Kryn, D.; Lacava, F.; Markiewicz, T.; Maurin, G.; Muirhead, H.; Muller, F.; Naumann, L.; Norton, A.; Petrucci, G.; Placci, A.; Revol, J.P.; Rijssenbeek, M.; Rohlf, J.; Rossi, P.; Rubbia, C.; Sadoulet, B.; Schinzel, D.; Tao, C.; Timmer, J.; Meer, S. van der; Vialle, J.P.; Vuillemin, V.; Xie, G.Y.; Zurfluh, E.; Cochet, C.; DeBeer, M.; Denegri, D.; Givernaud, A.; Laugier, J.P.; Leveque, A.; Locci, E.; Loret, M.; Malosse, J.J.; Rich, J.; Sass, R.; Saudraix, J.; Savoy-Navarro, A.; Spiro, M.; Dobrzynski, L.; Fontaine, G.; Geer, S.; Ghesquiere, C.; Giraud-Heraud, Y.; Mendiburu, J.P.; Orkin-Lecourtois, A.; Sajot, G.; Vrana, J.; Bacci, C.; Bowcock, T.J.V.; Corden, M.; Dallman, D.; Di Ciaccio, A.; Dowell, J.D.; Edwards, M.; Eggert, K.; Eisenhandler, E.; Erhard, P.; Faissner, H.; Frey, R.; Fruehwirth, R.; Garvey, J.; Giboni, K.L.; Gibson, W.R.; Gutierrez, P.; Hansl-Kozanecka, T.; Hodges, C.; Hoffmann, D.; Homer, R.J.; Honma, A.; Kalmus, P.I.P.; Karimaeki, V.; Keeler, R.; Kenyon, I.; Kernan, A.; Kinnunen, R.; Kozanecki, W.; Lehmann, H.; Leuchs, K.; McMahon, T.; Moricca, M.; Paoluzi, L.; Piano Mortari, G.; Pimiae, M.; Radermacher, E.; Ransdell, J.; Reithler, H.; Salvi, G.; Salvini, G.; Strauss, J.; Sumorok, K.; Szoncso, F.; Smith, D.; Thompson, G.; Tscheslog, E.; Tuominiemi, J.; Wahl, H.D.; Watkins, P.; Wilson, J.

    1983-01-01

    In this paper the physics of the events collected using this ''minimum bias trigger'' is described. After a brief description of the detector, I present results concerning particle production (pseudorapidity distributions, multiplicity and KNO scaling). Transverse energy distributions, long and short range correlations, and finally high psub(t) physics and jets. (orig./HSI)

  13. 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...

  14. 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...

  15. 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...

  16. 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 ...

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

    International Nuclear Information System (INIS)

    Wiedenmann, Werner

    2010-01-01

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

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. The fast trigger scintillator for the JETSET experiment (PS202/LEAR)

    International Nuclear Information System (INIS)

    Sefzick, T.

    1988-12-01

    In the present thesis the trigger detector of the JETSET experiment (PS202) at the LEAR/CERN consisting of scintillation counters is presented. After giving a start signal in a second stage of the trigger electronics the determination of the position of the traversed points of the reaction products is performed with the information of the scintillation detector. A third following trigger stage shall study the position informations given by the second stage under kinematical points of view. The present diploma thesis deals especially with the first two trigger stages. As basic conditions the components of a scintillation counter are treated and calibration and testing possibilities presented. For this belongs a fast light pulser with green or blue LED. Results of the studies which scintillator and light-guide materials are most suitable for the JETSET experiment are presented. (orig./HSI) [de

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

    CERN Document Server

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

    2016-01-01

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

  6. Reliability of physical examination for diagnosis of myofascial trigger points: a systematic review of the literature.

    Science.gov (United States)

    Lucas, Nicholas; Macaskill, Petra; Irwig, Les; Moran, Robert; Bogduk, Nikolai

    2009-01-01

    Trigger points are promoted as an important cause of musculoskeletal pain. There is no accepted reference standard for the diagnosis of trigger points, and data on the reliability of physical examination for trigger points are conflicting. To systematically review the literature on the reliability of physical examination for the diagnosis of trigger points. MEDLINE, EMBASE, and other sources were searched for articles reporting the reliability of physical examination for trigger points. Included studies were evaluated for their quality and applicability, and reliability estimates were extracted and reported. Nine studies were eligible for inclusion. None satisfied all quality and applicability criteria. No study specifically reported reliability for the identification of the location of active trigger points in the muscles of symptomatic participants. Reliability estimates varied widely for each diagnostic sign, for each muscle, and across each study. Reliability estimates were generally higher for subjective signs such as tenderness (kappa range, 0.22-1.0) and pain reproduction (kappa range, 0.57-1.00), and lower for objective signs such as the taut band (kappa range, -0.08-0.75) and local twitch response (kappa range, -0.05-0.57). No study to date has reported the reliability of trigger point diagnosis according to the currently proposed criteria. On the basis of the limited number of studies available, and significant problems with their design, reporting, statistical integrity, and clinical applicability, physical examination cannot currently be recommended as a reliable test for the diagnosis of trigger points. The reliability of trigger point diagnosis needs to be further investigated with studies of high quality that use current diagnostic criteria in clinically relevant patients.

  7. Search for New Physics Processes with Heavy Quark Signatures in the ATLAS Experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00388427

    A program involving searches for new physics with heavy quark final states using data from the ATLAS experiment at the LHC is presented here. The signal and expected backgrounds for the decay $B_{s}→μ^{+} μ^{-} μ^{+} μ^{-}$, a rare decay whose branching ratio may be enhanced by the presence of certain Beyond the Standard Model processes, are studied, and the groundwork is laid for a future analysis. Possible mediators include horizontal gauge bosons, supersymmetry via sgoldstinos, and interactions with the hidden sector. To this end, a set of twelve triggers have been selected and studied, and their efficiency figures of merit have been calculated. A truth trigger efficiency study was performed in order to determine if new triggers should be installed for the analysis. The backgrounds have been studied, and a mass window technique was used to reduce their amplitude relative to the signal. A proposal to improve the efficiency of some of the ATLAS High-Level B-physics Triggers, based on refining the selec...

  8. On a possible second-level trigger for the experiment DISTO

    International Nuclear Information System (INIS)

    Bussa, M.P.; Fava, L.; Ferrero, L.; Grasso, A.; Ivanov, V.V.; Kisel', I.V.; Konotopskaya, E.V.; Pontecorvo, G.B.; Joint Inst. for Nuclear Research, Dubna

    1995-01-01

    A two-level trigger is to be applied for suppression of the background and for effective selection of events involving short-lived Λ-, Σ- and φ-particles in the experiment DISTO. The first-level trigger is applied for track recognition, in searching for a secondary vertex, and for identifying the detected particles. 10 refs., 14 figs., 1 tab

  9. The second level trigger of the L3 experiment. Pt. 1

    International Nuclear Information System (INIS)

    Bertsch, Y.; Blaising, J.J.; Bonnefon, H.; Chollet-Le Flour, F.; Degre, A.; Dromby, G.; Lecoq, J.; Morand, R.; Moynot, M.; Perrot, G.; Riccadonna, X.

    1993-07-01

    The second level trigger of the L3 experiment performs online background rejection and reduces the first level trigger rate to a value fitting with the third level trigger processing capability. Designed around a set of 3 bit-slice XOP microprocessors, it can process up to 500 first level triggers per second without significant dead time in the data acquisition. The system described here ensures the L3 data taking since the beginning of LEP in July 1989 and the online rejection since 1990. (authors). 24 refs., 8 figs., 3 tabs

  10. Trigger design for a gamma ray detector of HIRFL-ETF

    Science.gov (United States)

    Du, Zhong-Wei; Su, Hong; Qian, Yi; Kong, Jie

    2013-10-01

    The Gamma Ray Array Detector (GRAD) is one subsystem of HIRFL-ETF (the External Target Facility (ETF) of the Heavy Ion Research Facility in Lanzhou (HIRFL)). It is capable of measuring the energy of gamma-rays with 1024 CsI scintillators in in-beam nuclear experiments. The GRAD trigger should select the valid events and reject the data from the scintillators which are not hit by the gamma-ray. The GRAD trigger has been developed based on the Field Programmable Gate Array (FPGAs) and PXI interface. It makes prompt trigger decisions to select valid events by processing the hit signals from the 1024 CsI scintillators. According to the physical requirements, the GRAD trigger module supplies 12-bit trigger information for the global trigger system of ETF and supplies a trigger signal for data acquisition (DAQ) system of GRAD. In addition, the GRAD trigger generates trigger data that are packed and transmitted to the host computer via PXI bus to be saved for off-line analysis. The trigger processing is implemented in the front-end electronics of GRAD and one FPGA of the GRAD trigger module. The logic of PXI transmission and reconfiguration is implemented in another FPGA of the GRAD trigger module. During the gamma-ray experiments, the GRAD trigger performs reliably and efficiently. The function of GRAD trigger is capable of satisfying the physical requirements.

  11. Trigger design for a gamma ray detector of HIRFL-ETF

    International Nuclear Information System (INIS)

    Du Zhongwei; Su Hong; Qian Yi; Kong Jie

    2013-01-01

    The Gamma Ray Array Detector (GRAD) is one subsystem of HIRFL-ETF (the External Target Facility (ETF) of the Heavy Ion Research Facility in Lanzhou (HIRFL)). It is capable of measuring the energy of gamma-rays with 1024 CsI scintillators in in-beam nuclear experiments. The GRAD trigger should select the valid events and reject the data from the scintillators which are not hit by the gamma-ray. The GRAD trigger has been developed based on the Field Programmable Gate Array (FPGAs) and PXI interface. It makes prompt trigger decisions to select valid events by processing the hit signals from the 1024 CsI scintillators. According to the physical requirements, the GRAD trigger module supplies 12-bit trigger information for the global trigger system of ETF and supplies a trigger signal for data acquisition (DAQ) system of GRAD. In addition, the GRAD trigger generates trigger data that are packed and transmitted to the host computer via PXI bus to be saved for off-line analysis. The trigger processing is implemented in the front-end electronics of GRAD and one FPGA of the GRAD trigger module. The logic of PXI transmission and reconfiguration is implemented in another FPGA of the GRAD trigger module. During the gamma-ray experiments, the GRAD trigger performs reliably and efficiently. The function of GRAD trigger is capable of satisfying the physical requirements. (authors)

  12. An Upgraded ATLAS Central Trigger for 2015 Luminosities

    International Nuclear Information System (INIS)

    Poettgen, Ruth; Gutenberg, Johannes

    2013-06-01

    The Central Trigger Processor (CTP) is a core unit of the first of three levels that constitute the ATLAS trigger system. Based on information from calorimeter and muon trigger processors as well as from some additional systems it produces the level-1 trigger decision and prompts the read-out of the sub-detectors. The increase in luminosity at the LHC has pushed the CTP operation to its design limits. In order to still satisfy the physics goals of the experiment after the shutdown of the LHC of 2013/2014 the CTP will be upgraded during this period. This article discusses the current Central Trigger Processor, the motivation for the upgrade, and the changes foreseen to meet the requirements of the post-2014 physics runs at the LHC. (authors)

  13. 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...

  14. Conceptual design of the first level trigger for the SDC experiment

    International Nuclear Information System (INIS)

    Drinkard, J.; Griffin, G.; Lankford, A.J.; Schmid, B.; Stoker, D.; Tarazi, J.; Lipniacka, A.; Brisson, J.C.; Hubbard, R.; Le Du, P.; Thooris, B.; Yashioka, H.; Hamatsu, R.; Nickerson, R.B.; Chapman, J.; Dunn, A.; Mann, J.; Miao, C.; Vejcik, S.; Dasu, S.; Gorski, T.; Lackey, J.; Smith, W.H.; Temple, W.; Coupal, D.

    1994-07-01

    We report on a conceptual design of the First Level Trigger for the SDC Experiment at the SSC. Level 1 algorithms employ barrel and intermediate trackers, and electromagnetic and hadronic calorimeters. Results of simulations of background rates and efficiencies are presented together with a discussion of the simulation method. Tracking and calorimetric triggers are discussed in detail. Some hardware implementation ideas for the trigger algorithms are mentioned. (authors). 8 refs., 4 figs., 2 tabs

  15. 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.

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

    CERN Document Server

    Wiedenmann, W

    2009-01-01

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

  17. A first-level calorimeter trigger for the ATLAS experiment

    International Nuclear Information System (INIS)

    Perera, V.; Edwards, J.; Gee, N.

    1995-01-01

    In the RD27 collaboration the authors have carried out system studies on the implementation of the first level calorimeter trigger processor system for the ATLAS experiment to be mounted at the Large Hadron Collider (LHC) at CERN. A demonstrator trigger system operated successfully with the RD3 and RD33 calorimeters at the full 40 MHz LHC bunch crossing (BC) rate. The prototype application-specific integrated circuits (ASICs) in this system each processed data from only a single trigger cell and its environment, which would lead to an extremely large system for ATLAS. Using eight-bit parallel data even the use of ASICs, processing multiple trigger cells would demand unacceptably large numbers of input pins and module connections. Initial studies of this I/O problem produced a solution based on asynchronous transmission of zero-suppressed and BC-tagged data on 160 Mbit/s serial links. This approach appeared to be feasible but would have introduced additional latency of about 20 BCs. Further studies have led to the design of a fully-synchronous calorimeter trigger processor system using commercial high-speed optical links. The links will terminate in multi-chip modules (MCMs) incorporating custom-designed integrated optics, and the trigger algorithms will be implemented in ASICs

  18. The experiment PANDA: physics with antiprotons at FAIR

    Directory of Open Access Journals (Sweden)

    Boca Gianluigi

    2015-01-01

    The PANDA experiment is designed to achieve the above mentioned physics goals with a setup with the following characteristics: an almost full solid angle acceptance; excellent tracking capabilities with high resolution (1–2 % at 1 GeV/c in the central region; secondary vertex detection with resolution ≈ 100 microns or better; electromagnetic calorimetry for detections of gammas and electrons up to 10 GeV; good particle identification of charge tracks (electrons, muons, pions, kaons, protons; a dedicated interchangeable central apparatus for the hypernuclear physics; detector and data acquisition system capable of working at 20 MHz interaction rate with an intelligent software trigger that can provide maximum flexibility.

  19. The ATLAS Run-2 Trigger Menu for higher luminosities: Design, Performance and Operational Aspects

    CERN Document Server

    Ruiz-Martinez, Aranzazu; The ATLAS collaboration

    2017-01-01

    The ATLAS experiment aims at recording about 1 kHz of physics collisions, starting with an LHC design bunch crossing rate of 40 MHz. To reduce the massive background rate while maintaining a high selection efficiency for rare physics events (such as beyond the Standard Model physics), a two-level trigger system is used. 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. A trigger menu is a compilation of these triggers which specifies the physics algorithms to be used during data taking and the bandwidth a given trigger is allocated. Trigger menus reflect not only the physics goals of the collaboration for a given run, but also take into consideration the instantaneous luminosity of the LHC and limitations from the...

  20. The ATLAS Run-2 Trigger Menu for higher luminosities: Design, Performance and Operational Aspects

    CERN Document Server

    Torro Pastor, Emma; The ATLAS collaboration

    2018-01-01

    The ATLAS experiment aims at recording about 1 kHz of physics collisions, starting with an LHC design bunch crossing rate of 40 MHz. To reduce the massive background rate while maintaining a high selection efficiency for rare physics events (such as beyond the Standard Model physics), a two-level trigger system is used. 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. A trigger menu is a compilation of these triggers which specifies the physics algorithms to be used during data taking and the bandwidth a given trigger is allocated. Trigger menus reflect not only the physics goals of the collaboration for a given run, but also take into consideration the instantaneous luminosity of the LHC and limitations from the...

  1. The design and performance of the ATLAS jet trigger

    International Nuclear Information System (INIS)

    Shimizu, Shima

    2014-01-01

    The ATLAS jet trigger is an important element of the event selection process, providing data samples for studies of Standard Model physics and searches for new physics at the LHC. The ATLAS jet trigger system has undergone substantial modifications over the past few years of LHC operations, as experience developed with triggering in a high luminosity and high event pileup environment. In particular, the region-of-interest based strategy has been replaced by a full scan of the calorimeter data at the third trigger level, and by a full scan of the level-1 trigger input at level-2 for some specific trigger chains. Hadronic calibration and cleaning techniques are applied in order to provide improved performance and increased stability in high luminosity data taking conditions. In this note we discuss the implementation and operational aspects of the ATLAS jet trigger during 2011 and 2012 data taking periods at the LHC.

  2. The ATLAS Tau Trigger

    International Nuclear Information System (INIS)

    Rados, Petar Kevin

    2013-06-01

    The tau lepton plays a crucial role in understanding particle physics at the Tera scale. One of the most promising probes of the Higgs boson coupling to fermions is with detector signatures involving taus. In addition, many theories beyond the Standard Model, such as supersymmetry and exotic particles (W' and Z'), predict new physics with large couplings to taus. The ability to trigger on hadronic tau decays is therefore critical to achieving the physics goals of the ATLAS experiment. The higher instantaneous luminosities of proton-proton collisions achieved by the Large Hadron Collider (LHC) in 2012 resulted in a larger probability of overlap (pile-up) between bunch crossings, and so it was critical for ATLAS to have an effective tau trigger strategy. The details of this strategy are summarized in this paper, and the results of the latest performance measurements are presented. (authors)

  3. 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...

  4. Online software trigger at PANDA/FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Donghee; Kliemt, Ralf; Nerling, Frank [Helmholtz-Institut Mainz (Germany); Denig, Achim [Institut fuer Kernphysik, Universitaet Mainz (Germany); Goetzen, Klaus; Peters, Klaus [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany); Collaboration: PANDA-Collaboration

    2014-07-01

    The PANDA experiment at FAIR will employ a novel trigger-less read-out system. Since a conventional hardware trigger concept is not suitable for PANDA, a high level online event filter will be applied to perform fast event selection based on physics properties of the reconstructed events. A trigger-less data stream implies an event selection with track reconstruction and pattern recognition to be performed online, and thus analysing data under real time conditions at event rates of up to 40 MHz.The projected data rate reduction of about three orders of magnitude requires an effective background rejection, while retaining interesting signal events. Real time event selection in the environment of hadronic reactions is rather challenging and relies on sophisticated algorithms for the software trigger. The implementation and the performance of physics trigger algorithms presently studied with realistic Monte Carlo simulations is discussed. The impact of parameters such as momentum or mass resolution, PID probability, vertex reconstruction and a multivariate analysis using the TMVA package for event filtering is presented.

  5. CT-TRX1, a triggered-reconnection compact toroid experiment

    International Nuclear Information System (INIS)

    Hoffman, A.L.

    1980-05-01

    A new compact toroid experiment, CT-TRX1, based on the field reversed theta pinch is under construction. The unique feature of this experiment is the incorporation of several quasi-steady and pulsed magnets to carefully control the reconnection process. The motivation for this emphasis is to duplicate and extend the results reported by Kurtmullaev, et al., where delayed reconnection produced efficient axial shock heating and resulted in large diameter compact toroids which exhibited complete MHD stability for the 100 μsec decay time of their pulsed magnets. CT-TRX1 incorporates moderate E/sub theta/ radial shock heating, along with the triggered reconnection capability, to investigate the full range of conditions between the USSR experiments and the radial shock heated experiments at LASL, where m = 2 rotational instabilities occur. An additional feature of CT-TRX1 is the incorporation of a compound magnet which will provide long magnetic field decay times. The requirements for both high field quasi-steady outer magnets, and several high voltage, individually triggered pulsed inner magnets, present unique engineering design problems which are discussed

  6. 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...

  7. 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. ...

  8. 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

    The measurement of the mixing angle θ 13 is the goal of several running and planned experiments. The experiments are either accelerator based (super)beam experiments (e.g. MINOS, T2K, Nova) or reactor anti-neutrino disappearance experiments (e.g. Daya Bay, RENO or Double Chooz). In order to measure or constrain θ 13 with the Double Chooz experiment the overall systematic errors have to be controlled at the one-percent or sub-percent level. The limitation of the systematic errors is achieved through various means and techniques. E.g. the experiment consists of two identical detectors at different baselines, which allow to make a differential anti-neutrino flux measurement, where basically only relative normalisation errors remain. The requirements on the systematic errors put also strong constraints on the quality of all components and materials used for both detectors, most prominently on the stability and radiopurity of the scintillator, the photomultiplier tubes, the vessels containing the detector liquids and the shielding against ambient radioactivity. The readout electronics, trigger and data acquisition system have to operate reliably as an integrated and highly efficient whole over several years. The trigger is provided by the Level-1 Trigger and Timing System, which is the subject of this thesis. It has to provide a highly efficient trigger (at the 0.1% level) for neutrino-induced events as well as for several types of background events. Its decision is realized in hardware and based on energy depositions in the muon veto and the target region. The Level-1 Trigger and Timing System furthermore provides a common System Clock and an absolute timestamp for each event. The Level-1 Trigger and Timing System consists of two types of VME modules, several Trigger Boards and a Trigger Master Board, which have been custom-designed and developed in the electronics workshop of our institute for this experiment and purpose, starting in 2005. In this thesis all

  9. 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

    The measurement of the mixing angle {theta}{sub 13} is the goal of several running and planned experiments. The experiments are either accelerator based (super)beam experiments (e.g. MINOS, T2K, Nova) or reactor anti-neutrino disappearance experiments (e.g. Daya Bay, RENO or Double Chooz). In order to measure or constrain {theta}{sub 13} with the Double Chooz experiment the overall systematic errors have to be controlled at the one-percent or sub-percent level. The limitation of the systematic errors is achieved through various means and techniques. E.g. the experiment consists of two identical detectors at different baselines, which allow to make a differential anti-neutrino flux measurement, where basically only relative normalisation errors remain. The requirements on the systematic errors put also strong constraints on the quality of all components and materials used for both detectors, most prominently on the stability and radiopurity of the scintillator, the photomultiplier tubes, the vessels containing the detector liquids and the shielding against ambient radioactivity. The readout electronics, trigger and data acquisition system have to operate reliably as an integrated and highly efficient whole over several years. The trigger is provided by the Level-1 Trigger and Timing System, which is the subject of this thesis. It has to provide a highly efficient trigger (at the 0.1% level) for neutrino-induced events as well as for several types of background events. Its decision is realized in hardware and based on energy depositions in the muon veto and the target region. The Level-1 Trigger and Timing System furthermore provides a common System Clock and an absolute timestamp for each event. The Level-1 Trigger and Timing System consists of two types of VME modules, several Trigger Boards and a Trigger Master Board, which have been custom-designed and developed in the electronics workshop of our institute for this experiment and purpose, starting in 2005. In

  10. The ATLAS Run-2 Trigger: Design, Menu, Performance and Operational Aspects

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00219584; The ATLAS collaboration

    2016-01-01

    The LHC, at design capacity, has a bunch-crossing rate of 40 MHz whereas the ATLAS experiment has an average recording rate of about 1000 Hz. To reduce the rate of events but still maintain high efficiency of selecting rare events such as physics signals beyond the Standard Model, a two-level trigger system is used in ATLAS. Events are selected based on physics signatures such as presence of energetic leptons, photons, jets or large missing energy. Despite the limited time available for processing collision events, the trigger system is able to exploit topological informations, as well as using multi-variate methods. In total, the ATLAS trigger systems consists of thousands of different individual triggers. The ATLAS trigger menu specifies which triggers are used during data taking and how much rate a given trigger is allocated. This menu reflects not only the physics goals of the collaboration but also takes into consideration the instantaneous luminosity of the LHC and the design limits of the ATLAS detecto...

  11. Development of a highly selective muon trigger exploiting the high spatial resolution of monitored drift-tube chambers for the ATLAS experiment at the HL-LHC

    CERN Document Server

    Kortner, Oliver; The ATLAS collaboration

    2018-01-01

    The High-Luminosity LHC will provide the unique opportunity to explore the nature of physics beyond the Standard Model. Highly selective first level triggers are essential for the physics programme of the ATLAS experiment at the HL-LHC, where the instantaneous luminosity will exceed the LHC design instantaneous luminosity by almost an order of magnitude. The ATLAS first level muon trigger rate is dominated by low momentum muons, selected due to the moderate momentum resolution of the current system. This first level trigger limitation can be overcome by including data from the precision muon drift tube (MDT) chambers. This requires the fast continuous transfer of the MDT hits to the off-detector trigger logic and a fast track reconstruction algorithm performed in the trigger logic. The feasibility of this approach was studied with LHC collision data and simulated data. Two main options for the hardware implementation will be studied with demonstrators: an FPGA based option with an embedded ARM microprocessor ...

  12. Development of a Highly Selective Muon Trigger Exploiting the High Spatial Resolution of Monitored Drift-Tube Chambers for the ATLAS Experiment at the HL-LHC

    CERN Document Server

    Kortner, Oliver; The ATLAS collaboration

    2018-01-01

    The High-Luminosity LHC will provide the unique opportunity to explore the nature of physics beyond the Standard Model. Highly selective first level triggers are essential for the physics programme of the ATLAS experiment at the HL-LHC, where the instantaneous luminosity will exceed the LHC design instantaneous luminosity by almost an order of magnitude. The ATLAS first level muon trigger rate is dominated by low momentum muons, selected due to the moderate momentum resolution of the current system. This first level trigger limitation can be overcome by including data from the precision muon drift tube (MDT) chambers. This requires the fast continuous transfer of the MDT hits to the off-detector trigger logic and a fast track reconstruction algorithm performed in the trigger logic. The feasibility of this approach was studied with LHC collision data and simulated data. Two main options for the hardware implementation are currently studied with demonstrators, an FPGA based option with an embedded ARM microproc...

  13. 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.

  14. A demonstration of a Time Multiplexed Trigger for the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, R; Newbold, D [University of Bristol, H.H. Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Fayer, S; Hall, G; Hunt, C; Iles, G; Rose, A [Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2BW (United Kingdom)

    2012-01-15

    A novel approach to first-level hardware triggering in the LHC experiments has been studied and a prototype system built. Calorimeter trigger primitive data ( {approx} 5 Tb/s) are re-organised and time-multiplexed so that a single processing node (FPGA) may access the data corresponding to the entire detector for a given bunch crossing. This provides maximal flexibility in the construction of new trigger algorithms, which will be an important factor in ensuring adequate trigger performance at the very high levels of background expected at the upgraded LHC. A test system that incorporates all the key technologies for a final system and demonstrates the time-multiplexing and algorithm performance is presented.

  15. Pulling the trigger on LHC electronics

    CERN Document Server

    CERN. Geneva

    2001-01-01

    The conditions at CERN's Large Hadron Collider pose severe challenges for the designers and builders of front-end, trigger and data acquisition electronics. A recent workshop reviewed the encouraging progress so far and discussed what remains to be done. The LHC experiments have addressed level one trigger systems with a variety of high-speed hardware. The CMS Calorimeter Level One Regional Trigger uses 160 MHz logic boards plugged into the front and back of a custom backplane, which provides point-to-point links between the cards. Much of the processing in this system is performed by five types of 160 MHz digital applications-specific integrated circuits designed using Vitesse submicron high-integration gallium arsenide gate array technology. The LHC experiments make extensive use of field programmable gate arrays (FPGAs). These offer programmable reconfigurable logic, which has the flexibility that trigger designers need to be able to alter algorithms so that they can follow the physics and detector perform...

  16. Electronic system of the RPC Muon Trigger in CMS experiment at LHC accelerator (Elektroniczny system trygera mionowego RPC w eksperymencie CMS akceleratora LHC

    CERN Document Server

    Bialkowska, H

    2009-01-01

    This paper presents implementation of distributed, multichannel electronic measurement system for RPC - based Muon Trigger in the CMS experiment at LHC. The introduction shortly describes the research aims of LHC and shows the metrological requirements for CMS - good spatial and time resolution, and possibility to estimate multiple physical parameters from registered collisions of particles. Further the paper describes RPC Muon Trigger consisting of 200 000 independent channels for position measurement. The first part of the paper presents the functional structure of the system in the context of requirements put by the CMS experiment, like global triggering system and data acquisition. The second part describes the hardware solutions used in particular parts of the RPC detector measuremnt system and shows some test results. The paper has a digest and overview nature.

  17. 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 ...

  18. Graphics Processing Units for HEP trigger systems

    International Nuclear Information System (INIS)

    Ammendola, R.; Bauce, M.; Biagioni, A.; Chiozzi, S.; Cotta Ramusino, A.; Fantechi, R.; Fiorini, M.; Giagu, S.; Gianoli, A.; Lamanna, G.; Lonardo, A.; Messina, A.

    2016-01-01

    General-purpose computing on GPUs (Graphics Processing Units) 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 throughput, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming ripe. We will discuss the use of online parallel computing on GPU for synchronous low level trigger, focusing on CERN NA62 experiment trigger system. The use of GPU in higher level trigger system is also briefly considered.

  19. Graphics Processing Units for HEP trigger systems

    Energy Technology Data Exchange (ETDEWEB)

    Ammendola, R. [INFN Sezione di Roma “Tor Vergata”, Via della Ricerca Scientifica 1, 00133 Roma (Italy); Bauce, M. [INFN Sezione di Roma “La Sapienza”, P.le A. Moro 2, 00185 Roma (Italy); University of Rome “La Sapienza”, P.lee A.Moro 2, 00185 Roma (Italy); Biagioni, A. [INFN Sezione di Roma “La Sapienza”, P.le A. Moro 2, 00185 Roma (Italy); Chiozzi, S.; Cotta Ramusino, A. [INFN Sezione di Ferrara, Via Saragat 1, 44122 Ferrara (Italy); University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Fantechi, R. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); CERN, Geneve (Switzerland); Fiorini, M. [INFN Sezione di Ferrara, Via Saragat 1, 44122 Ferrara (Italy); University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Giagu, S. [INFN Sezione di Roma “La Sapienza”, P.le A. Moro 2, 00185 Roma (Italy); University of Rome “La Sapienza”, P.lee A.Moro 2, 00185 Roma (Italy); Gianoli, A. [INFN Sezione di Ferrara, Via Saragat 1, 44122 Ferrara (Italy); University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Lamanna, G., E-mail: gianluca.lamanna@cern.ch [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044 Frascati (Roma) (Italy); Lonardo, A. [INFN Sezione di Roma “La Sapienza”, P.le A. Moro 2, 00185 Roma (Italy); Messina, A. [INFN Sezione di Roma “La Sapienza”, P.le A. Moro 2, 00185 Roma (Italy); University of Rome “La Sapienza”, P.lee A.Moro 2, 00185 Roma (Italy); and others

    2016-07-11

    General-purpose computing on GPUs (Graphics Processing Units) 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 throughput, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming ripe. We will discuss the use of online parallel computing on GPU for synchronous low level trigger, focusing on CERN NA62 experiment trigger system. The use of GPU in higher level trigger system is also briefly considered.

  20. 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

  1. 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.

  2. ATLAS Level-1 Calorimeter Trigger: Status and Development

    CERN Document Server

    Bracinik, J; The ATLAS collaboration

    2013-01-01

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

  3. GPU Enhancement of the Trigger to Extend Physics Reach at the LHC

    CERN Document Server

    Lujan, P.; Hunt, A.; Jindal, P.; LeGresley, P.

    2014-01-01

    At the Large Hadron Collider (LHC), the trigger systems for the detectors must be able to process a very large amount of data in a very limited amount of time, so that the nominal collision rate of 40 MHz can be reduced to a data rate that can be stored and processed in a reasonable amount of time. This need for high performance places very stringent requirements on the complexity of the algorithms that can be used for identifying events of interest in the trigger system, which potentially limits the ability to trigger on signatures of various new physics models. In this paper, we present an alternative tracking algorithm, based on the Hough transform, which avoids many of the problems associated with the standard combinatorial track finding currently used. The Hough transform is also well-adapted for Graphics Processing Unit (GPU)-based computing, and such GPU-based systems could be easily integrated into the existing High-Level Trigger (HLT). This algorithm offers the ability to trigger on topological signa...

  4. 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...

  5. A silicon track trigger for the DOe experiment

    International Nuclear Information System (INIS)

    Narain, Meenakshi

    2000-01-01

    The design of a processor to trigger on long-lived particles (e.g. b-quarks) for the DOe experiment at the Fermilab Tevatron is presented. This device reconstructs the trajectory of the charged particles in the DOe tracking system, which consists of a central fiber tracker and a silicon microstrip tracker. The r-phi impact parameter resolution of the fitted tracks is about 40 μm. This enables the identification of the long-lived b-quarks produced in the decays of various particles, e.g. the top quarks, Higgs Boson, techni-particles and other exotic particles produced in pp-bar collisions at the Tevatron. In this report we describe the design of the architecture and algorithms for the Silicon Track Trigger

  6. A silicon track trigger for the DOe experiment

    CERN Document Server

    Narain, M

    2000-01-01

    The design of a processor to trigger on long-lived particles (e.g. b-quarks) for the DOe experiment at the Fermilab Tevatron is presented. This device reconstructs the trajectory of the charged particles in the DOe tracking system, which consists of a central fiber tracker and a silicon microstrip tracker. The r-phi impact parameter resolution of the fitted tracks is about 40 mu m. This enables the identification of the long-lived b-quarks produced in the decays of various particles, e.g. the top quarks, Higgs Boson, techni-particles and other exotic particles produced in pp-bar collisions at the Tevatron. In this report we describe the design of the architecture and algorithms for the Silicon Track Trigger.

  7. The ATLAS Level-1 Trigger Timing Setup

    CERN Document Server

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

    2005-01-01

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

  8. The ATLAS Run-2 Trigger: Design, Menu, Performance and Operational Aspects

    CERN Document Server

    Martin, Tim; The ATLAS collaboration

    2016-01-01

    The LHC, at design capacity, has a bunch-crossing rate of 40 MHz whereas the ATLAS experiment at the LHC has an average recording rate of about 1000 Hz. To reduce the rate of events but still maintain a high efficiency of selecting rare events such as physics signals beyond the Standard Model, a two-level trigger system is used in ATLAS. Events are selected based on physics signatures such as presence of energetic leptons, photons, jets or large missing energy. Despite the limited time available for processing collision events, the trigger system is able to exploit topological information, as well as using multi-variate methods. In total, the ATLAS trigger system consists of thousands of different individual triggers. The ATLAS trigger menu specifies which triggers are used during data taking and how much rate a given trigger is allocated. This menu reflects not only the physics goals of the collaboration but also takes the instantaneous luminosity of the LHC, the design limits of the ATLAS detector and the o...

  9. 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.

  10. 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...

  11. 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.

  12. Conceptual investigations of a trigger extension for muons from pp collisions in the CMS experiment

    International Nuclear Information System (INIS)

    Erdogan, Yusuf

    2015-01-01

    As of 2023, the Large Hadron Collider can provide its experiments with five to ten times more luminosity than the current design value of 10 34 cm -2 s -1 . This upgrade will allow for the measurement of physics processes with very small cross sections. However, at these high luminosities, due to the pileup interactions, the detector occupancy will be very high. This will cause, on the one hand, a systematic increase of the trigger rates for single muons. On the other hand, amplified by the limited momentum resolution of the muon system, mismeasurements of the transverse momenta of muons will be dominant in the high momentum regime. In this region, the trigger rate distribution will saturate and the rate limitation with a transverse momentum threshold will be difficult. Furthermore, the quality of the single muon trigger at Level 1 will be decreased due to coincident particle transitions causing ambiguities in the innermost muon chambers. In 2007, a concept called Muon Track fast Tag (MTT) was introduced to address these trigger challenges. The studies, performed in this thesis, are divided into three parts. Concerning the MTT proposal, the main part deals with conceptual investigations on the possible trigger extension for muons from proton proton collisions in the CMS experiment. Thereby, the focus lies on the fundamental question of the muon detection capability of a scintillator system with SiPM readout. Such a system is the Hadron Outer calorimeter of CMS which is used for studies to answer this question. In the second part, the integration of the MTT system in the geometry description of the CMS detector is outlined. Thereby, it is written as a technical recipe which allows the understanding of the implementation of a new detector system in the CMS detector description. The last part of this thesis focuses on the Geant 4 simulations of the first MTT prototype. In this part, together with the simulation setup, selected results are introduced.

  13. High-level trigger system for the LHC ALICE experiment

    CERN Document Server

    Bramm, R; Lien, J A; Lindenstruth, V; Loizides, C; Röhrich, D; Skaali, B; Steinbeck, T M; Stock, Reinhard; Ullaland, K; Vestbø, A S; Wiebalck, A

    2003-01-01

    The central detectors of the ALICE experiment at LHC will produce a data size of up to 75 MB/event at an event rate less than approximately equals 200 Hz resulting in a data rate of similar to 15 GB/s. Online processing of the data is necessary in order to select interesting (sub)events ("High Level Trigger"), or to compress data efficiently by modeling techniques. Processing this data requires a massive parallel computing system (High Level Trigger System). The system will consist of a farm of clustered SMP-nodes based on off- the-shelf PCs connected with a high bandwidth low latency network.

  14. 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.

  15. 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...

  16. 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

  17. Combining triggers in HEP data analysis

    International Nuclear Information System (INIS)

    Lendermann, Victor; Herbst, Michael; Krueger, Katja; Schultz-Coulon, Hans-Christian; Stamen, Rainer; Haller, Johannes

    2009-01-01

    Modern high-energy physics experiments collect data using dedicated complex multi-level trigger systems which perform an online selection of potentially interesting events. In general, this selection suffers from inefficiencies. A further loss of statistics occurs when the rate of accepted events is artificially scaled down in order to meet bandwidth constraints. An offline analysis of the recorded data must correct for the resulting losses in order to determine the original statistics of the analysed data sample. This is particularly challenging when data samples recorded by several triggers are combined. In this paper we present methods for the calculation of the offline corrections and study their statistical performance. Implications on building and operating trigger systems are discussed. (orig.)

  18. Combining triggers in HEP data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lendermann, Victor; Herbst, Michael; Krueger, Katja; Schultz-Coulon, Hans-Christian; Stamen, Rainer [Heidelberg Univ. (Germany). Kirchhoff-Institut fuer Physik; Haller, Johannes [Hamburg Univ. (Germany). Institut fuer Experimentalphysik

    2009-01-15

    Modern high-energy physics experiments collect data using dedicated complex multi-level trigger systems which perform an online selection of potentially interesting events. In general, this selection suffers from inefficiencies. A further loss of statistics occurs when the rate of accepted events is artificially scaled down in order to meet bandwidth constraints. An offline analysis of the recorded data must correct for the resulting losses in order to determine the original statistics of the analysed data sample. This is particularly challenging when data samples recorded by several triggers are combined. In this paper we present methods for the calculation of the offline corrections and study their statistical performance. Implications on building and operating trigger systems are discussed. (orig.)

  19. Physical and chemical trigger factors in environmental intolerance.

    Science.gov (United States)

    Claeson, Anna-Sara; Palmquist, Eva; Nordin, Steven

    2018-04-01

    Individuals with environmental intolerance (EI) react to exposure from different environmental sources at levels tolerated by most people and that are below established toxicological and hazardous thresholds. The main aim of this study was to determine the prevalence of attributing symptoms to chemical and physical sources in the environment among individuals with different forms of self-reported EI and in referents. Cross-sectional data from a population-based study, the Västerbotten Environmental Health Study (n = 3406), were used and individuals with self-reported EI to chemicals, buildings, electromagnetic fields and sounds as well as a group with multiple EIs were identified. The Environmental-Symptom Attribution Scale was used to quantify degree to which health symptoms are attributed to 40 specific environmental exposures and sources, with subscales referring to the four types of EI. All EI groups, except the group with building related intolerance (BRI), reported more symptoms from the expected sources compared to the referents. In addition, individuals with chemical and sound intolerance reported symptoms from building related trigger factors, and individuals with electromagnetic hypersensitivity reported symptoms from chemical trigger factors. The study suggests that individuals with BRI react to fewer and more specific trigger factors than do individuals with other EIs, and that it is important to ask about different sources since three of the EI groups attribute their symptoms to a wide variety of sources in addition to the sources to which their EI implicates. Copyright © 2018 Elsevier GmbH. All rights reserved.

  20. 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)

  1. 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...

  2. The ATLAS Tau Trigger

    CERN Document Server

    Dam, M; The ATLAS collaboration

    2009-01-01

    The ATLAS experiment at CERN’s LHC has implemented a dedicated tau trigger system to select hadronically decaying tau leptons from the enormous background of QCD jets. This promises a significant increase in the discovery potential to the Higgs boson and in searches for physics beyond the Standard Model. The three level trigger system has been optimised for effciency and good background rejection. The first level uses information from the calorimeters only, while the two higher levels include also information from the tracking detectors. Shower shape variables and the track multiplicity are important variables to distinguish taus from QCD jets. At the initial lumonosity of 10^31 cm^−2 s^−1, single tau triggers with a transverse energy threshold of 50 GeV or higher can be run standalone. Below this level, the tau signatures will be combined with other event signature

  3. The ATLAS Run-2 Trigger Menu for higher luminosities: Design, Performance and Operational Aspects

    CERN Document Server

    Montejo Berlingen, Javier; The ATLAS collaboration

    2017-01-01

    The LHC, at design capacity, has a bunch-crossing rate of 40 MHz whereas the ATLAS experiment has an average recording rate of about 1 kHz. To reduce the rate of events, but maintain high selection efficiency for rare events such as physics signals beyond the Standard Model, a two-level trigger system is used. Events are selected based on physics signatures such as presence of energetic leptons, photons, jets or large missing energy. Despite the limited time available for processing collision events the trigger system is able to exploit topological information, as well as using multi-variate methods. In total, the ATLAS trigger systems consists of thousands of different individual triggers. The ATLAS trigger menu specifies which triggers are used during data taking and how much rate a given trigger is allocated. This menu reflects not only the physics goals of the collaboration but also takes into consideration the instantaneous luminosity of the LHC and the design limits of the ATLAS detector and offline pro...

  4. Trigger and data-acquisition challenges at the LHC

    CERN Multimedia

    CERN. Geneva

    2003-01-01

    We review the main requirements placed on the Trigger and Data Acquisition (DAQ systems of the LHC experiments by their rich physics program and the LHC environment. A description of the architecture of the various systems, the motivation of each alternative and the conceptual design of each filtering stage will be discussed. We will then turn to a description of the major elements of the three distinct sub-systems, namely the Level-1 trigger, the DAQ with particular attention to the Event-Building and overall control and monitor, and finally the High-Level trigger system and the online farms.

  5. 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.

  6. Review of trigger and on-line processors at SLAC

    International Nuclear Information System (INIS)

    Lankford, A.J.

    1984-07-01

    The role of trigger and on-line processors in reducing data rates to manageable proportions in e + e - physics experiments is defined not by high physics or background rates, but by the large event sizes of the general-purpose detectors employed. The rate of e + e - annihilation is low, and backgrounds are not high; yet the number of physics processes which can be studied is vast and varied. This paper begins by briefly describing the role of trigger processors in the e + e - context. The usual flow of the trigger decision process is illustrated with selected examples of SLAC trigger processing. The features are mentioned of triggering at the SLC and the trigger processing plans of the two SLC detectors: The Mark II and the SLD. The most common on-line processors at SLAC, the BADC, the SLAC Scanner Processor, the SLAC FASTBUS Controller, and the VAX CAMAC Channel, are discussed. Uses of the 168/E, 3081/E, and FASTBUS VAX processors are mentioned. The manner in which these processors are interfaced and the function they serve on line is described. Finally, the accelerator control system for the SLC is outlined. This paper is a survey in nature, and hence, relies heavily upon references to previous publications for detailed description of work mentioned here. 27 references, 9 figures, 1 table

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

    CERN Document Server

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

    2016-01-01

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

  8. Physics issues on triggering

    Indian Academy of Sciences (India)

    The detectors at the ILC are planned to run without hardware trigger. The ... as not coming from the interaction point and not matching to the silicon detectors ... electrons so that additional dE/dx cuts can help, making also here a factor 10 or.

  9. 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...

  10. The Topological Processor for the future ATLAS Level-1 Trigger

    CERN Document Server

    Kahra, C; The ATLAS collaboration

    2014-01-01

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

  11. The BTeV trigger system

    International Nuclear Information System (INIS)

    Kaplan, D.M.

    2000-01-01

    BTeV is a dedicated beauty and charm experiment proposed for the Fermilab Tevatron. The broad physics program envisaged for BTeV requires a trigger that is efficient for a wide variety of heavy-quark decays, including those to all-hadronic final states. To achieve this, we plan to trigger on evidence of detached vertices at the very first trigger level, taking advantage of fast-readout pixel detectors to facilitate fast pattern recognition. Simulations show that 100-to-1 rejection of light-quark background events can be achieved at Level 1 using specialized trackfinding hardware, and that an additional factor of 10-100 in data reduction can be achieved using general purpose processor farms at Levels 2 and 3. This is adequate to allow data taking at luminosities in excess of 2x10 32 cm -2 s -1

  12. Pattern Recognition in the TRT for the ATLAS B-Physics Trigger

    CERN Document Server

    Baines, J T M; Hinkelbein, C; Kugel, A; Männer, R; Müller, M; Sessler, M; Simmler, H; Singpiel, H; Smizanska, M

    1999-01-01

    The current B-physics trigger strategy in LVL2 starts with a scan of the full volume of the TRT to reconstruct all tracks with pT > 0.5 GeV. Since the detector volume to be analysed is 100 times larger than a typical RoI, and the pT range of the track search extends down to 0.5 GeV, an additional factor of 10 in processing power is required in comparison with the high-pT TRT feature extraction algorithm which has a 5 GeV threshold. At low luminosity, the full scan will be performed as part of the B-physics trigger with a frequency of 9 kHz. Taking into account all these factors, the full scan at low luminosity will require 100 times more computing power than the RoI-guided scan at design luminosity. It is the most challenging of all LVL2 algorithms in terms of computing power and bandwidth requirements. A very fast and therefore simple algorithm is thus essential, independent of the hardware realisation. This paper presents a TRT track reconstruction algorithm which is based on a Hough Transform using a look-...

  13. A Fast Hardware Tracker for the ATLAS Trigger System

    CERN Document Server

    Neubauer, Mark S

    2011-01-01

    In hadron collider experiments, triggering the detector to store interesting events for offline analysis is a challenge due to the high rates and multiplicities of particles produced. Maintaining high trigger efficiency for the physics we are most interested in while at the same time suppressing high rate physics from inclusive QCD processes is a difficult but important problem. It is essential that the trigger system be flexible and robust, with sufficient redundancy and operating margin. Providing high quality track reconstruction over the full ATLAS detector by the start of processing at LVL2 is an important element to achieve these needs. As the instantaneous luminosity increases, the computational load on the LVL2 system will significantly increase due to the need for more sophisticated algorithms to suppress backgrounds. The Fast Tracker (FTK) is a proposed upgrade to the ATLAS trigger system. It is designed to enable early rejection of background events and thus leave more LVL2 execution time by moving...

  14. A Level 1 Tracking Trigger for the CMS Experiment at the LHC Phase 2 Luminosity Upgrade

    CERN Document Server

    Pozzobon, Nicola

    2011-01-01

    The second decade of Large Hadron Collider operations, from about 2020 onwards, envisages a remarkable increase in collider instantaneous luminosity, one order of magnitude above the project one. This luminosity increase presents several challenges to the LHC experiments. The present tracker of the Compact Muon Solenoid experiment must be replaced with a system providing excellent tracking quality at higher luminosities, as well as Tracking Trigger inputs to the existing “Level 0” CMS trigger system at the full 40 MHz bunch-crossing rate. The minimal requirements for a Tracking Trigger would be the capability to confirm the presence of high-pT tracks associated with Calorimeter and/or Muon Level 0 triggers. The ability to provide eective isolation criteria may also be required, and would in any case substantially improve the Trigger performance. Maintaining the data rates generated by Tracking Trigger inputs within a manageable bandwidth requires sensor modules able to locally sparsify the data. Measuring...

  15. 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...

  16. Muon triggers in search for charm and beauty in hybrid emulsion experiments

    International Nuclear Information System (INIS)

    Romano, G.

    1984-01-01

    This chapter presents calculations which are mainly based on the results obtained with the dump used in the experiment NA19 at CERN. The easiest way to trigger on muons (even on-line) is to place a dump behind the target. Background triggers are due to muons produced in the primary interaction (mainly Drell-Yan) or resulting from short lived particles (charm decays are a source of background in a search for beauty) or from long lived particle decays. Among the possible on-line and/or off-line triggers, those based on the presence of one or more muons seem particularly promising due to the sizeable branching ratio of the new flavors into leptons and to the good selection power against background. Charmed and beauty particles produce, on average, muons with much higher transverse momenta than background, and thus a trigger requiring a low number of muons (1 or 2) could be equally or even more selective than a multimuon trigger, while keeping a larger fraction of the signal

  17. 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.

  18. Development of a novel scintillation-trigger detector for the MTV experiment using aluminum-metallized film tapes

    Science.gov (United States)

    Tanaka, S.; Ozaki, S.; Sakamoto, Y.; Tanuma, R.; Yoshida, T.; Murata, J.

    2014-07-01

    A new type of a trigger-scintillation counter array designed for the MTV experiment at TRIUMF-ISAC has been developed, which uses aluminum-metallized film tape for wrapping to achieve the required assembling precision of ±0.5 mm. The MTV experiment uses a cylindrical drift chamber (CDC) as the main electron-tracking detector. The barrel-type trigger counter is placed inside the CDC to generate a trigger signal using 1 mm thick, 300 mm long thin plastic scintillation counters. Detection efficiency and light attenuation compared with conventional wrapping materials are studied.

  19. Development of a novel scintillation-trigger detector for the MTV experiment using aluminum-metallized film tapes

    International Nuclear Information System (INIS)

    Tanaka, S.; Ozaki, S.; Sakamoto, Y.; Tanuma, R.; Yoshida, T.; Murata, J.

    2014-01-01

    A new type of a trigger-scintillation counter array designed for the MTV experiment at TRIUMF-ISAC has been developed, which uses aluminum-metallized film tape for wrapping to achieve the required assembling precision of ±0.5 mm. The MTV experiment uses a cylindrical drift chamber (CDC) as the main electron-tracking detector. The barrel-type trigger counter is placed inside the CDC to generate a trigger signal using 1 mm thick, 300 mm long thin plastic scintillation counters. Detection efficiency and light attenuation compared with conventional wrapping materials are studied

  20. Graphical processors for HEP trigger systems

    Energy Technology Data Exchange (ETDEWEB)

    Ammendola, R. [INFN Sezione di Roma Tor Vergata, Via della Ricerca Scientifica, 1, 00133 Roma (Italy); Biagioni, A. [INFN Sezione di Roma, P.le Aldo Moro, 2, 00185 Roma (Italy); Chiozzi, S.; Cotta Ramusino, A. [INFN Sezione di Ferrara, Via Saragat, 1, 44122 Ferrara (Italy); Di Lorenzo, S. [INFN Sezione di Pisa, L. Bruno Pontecorvo, 3, 56127 Pisa (Italy); Università di Pisa, Lungarno Pacinotti 43, 56126 Pisa (Italy); Fantechi, R. [INFN Sezione di Pisa, L. Bruno Pontecorvo, 3, 56127 Pisa (Italy); Fiorini, M. [INFN Sezione di Ferrara, Via Saragat, 1, 44122 Ferrara (Italy); Università di Ferrara, Via Ludovico Ariosto 35, 44121 Ferrara (Italy); Frezza, O. [INFN Sezione di Roma, P.le Aldo Moro, 2, 00185 Roma (Italy); Lamanna, G. [INFN, Laboratori Nazionali di Frascati (Italy); Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P.S.; Pastorelli, E. [INFN Sezione di Roma, P.le Aldo Moro, 2, 00185 Roma (Italy); Piandani, R. [INFN Sezione di Pisa, L. Bruno Pontecorvo, 3, 56127 Pisa (Italy); Pontisso, L., E-mail: luca.pontisso@cern.ch [INFN Sezione di Pisa, L. Bruno Pontecorvo, 3, 56127 Pisa (Italy); Rossetti, D. [NVIDIA Corp., Santa Clara, CA (United States); Simula, F. [INFN Sezione di Roma, P.le Aldo Moro, 2, 00185 Roma (Italy); Sozzi, M. [INFN Sezione di Pisa, L. Bruno Pontecorvo, 3, 56127 Pisa (Italy); Università di Pisa, Lungarno Pacinotti 43, 56126 Pisa (Italy); and others

    2017-02-11

    General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to employ GPUs as accelerators in offline computations. With the steady decrease of GPU latencies and the increase in link and memory throughputs, time is ripe for real-time applications using GPUs in high-energy physics data acquisition and trigger systems. We will discuss the use of online parallel computing on GPUs for synchronous low level trigger systems, focusing on tests performed on the trigger of the CERN NA62 experiment. Latencies of all components need analysing, networking being the most critical. To keep it under control, we envisioned NaNet, an FPGA-based PCIe Network Interface Card (NIC) enabling GPUDirect connection. Moreover, we discuss how specific trigger algorithms can be parallelised and thus benefit from a GPU implementation, in terms of increased execution speed. Such improvements are particularly relevant for the foreseen LHC luminosity upgrade where highly selective algorithms will be crucial to maintain sustainable trigger rates with very high pileup.

  1. Graphical processors for HEP trigger systems

    International Nuclear Information System (INIS)

    Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cotta Ramusino, A.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P.S.; Pastorelli, E.; Piandani, R.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.

    2017-01-01

    General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to employ GPUs as accelerators in offline computations. With the steady decrease of GPU latencies and the increase in link and memory throughputs, time is ripe for real-time applications using GPUs in high-energy physics data acquisition and trigger systems. We will discuss the use of online parallel computing on GPUs for synchronous low level trigger systems, focusing on tests performed on the trigger of the CERN NA62 experiment. Latencies of all components need analysing, networking being the most critical. To keep it under control, we envisioned NaNet, an FPGA-based PCIe Network Interface Card (NIC) enabling GPUDirect connection. Moreover, we discuss how specific trigger algorithms can be parallelised and thus benefit from a GPU implementation, in terms of increased execution speed. Such improvements are particularly relevant for the foreseen LHC luminosity upgrade where highly selective algorithms will be crucial to maintain sustainable trigger rates with very high pileup.

  2. 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...

  3. 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...

  4. Track Reconstruction and b-Jet Identification for the ATLAS Trigger System

    CERN Document Server

    Coccaro, A; The ATLAS collaboration

    2011-01-01

    A sophisticated trigger system, capable of real-time track reconstruction, is in place in the ATLAS experiment, to reject most of the events containing uninteresting background collisions while preserving as much as possible the interesting physics signals. The strategy adopted for fast reconstruction of charged tracks and in particular its application to the selection of jets from the hadronization of b-quarks is reviewed. Track reconstruction is routinely used for selection based on various physics objects while b-jet triggers are actively selecting events from the beginning of the 2011 LHC data-taking campaign.

  5. Evaluation of technologies of parallel computers. Communication networks for a real-time triggering application for a high-energy physics experiment at CERN

    International Nuclear Information System (INIS)

    Hoertnagl, Ch.

    1997-12-01

    Experiments at the future Large Hadron Collider (LHC) at CERN will be faced with an extraordinary challenge of event selection in real time. The primary event rate, equal to the bunch crossing frequency of 40 MHz, will have to be reduced by a factor of almost one-in-a-million in order to reveal traces of rare physics processes from an abundant background. This work presents various contributions to ongoing feasibility studies concerning the possible use of commercial technologies from the proximities of parallel computers and their communication networks for the second trigger stage, which faces an average data input rate of 100 kHz. Studies in this thesis apply a combination of methodologies, namely the build-up of lab-scale prototype implementations (including their exposition to test beam runs), algorithm development, technology tracking and benchmarking, as well as discrete event simulation. The main contribution consists of several technology case studies, which are based on the exploration of a set of standard benchmark programs for revealing simple parameters for characterizing delays during communication. Studied technologies include the communication sub-system of the Meiko CS-2, Asynchronous Transfer Mode (ATM), MEMORY CHANNEL, and Scalable Coherent Interface (SCI); all could be considered typical for candidate technologies. The discussion sheds light on the relative benefits and costs associated with different parallel programming models, in general, and with the use of message-passing libraries, such as Message Passing Interface (MPI), in particular. Best observed end-user-to-end-user latencies were ∼ 10 μs, best asymptotic bandwidths were ∼ 70 MByte/s. Typical sub-patterns of communication that have to be applied in the second trigger stage were sustained at ∼ 13 kHz, using today's technologies in realistic embeddings. (author)

  6. 3rd International School of Trigger and Data Acquisition - Cracow (Poland), 1 – 8 February 2012

    CERN Multimedia

    Yi Ling

    2011-01-01

    After two successful editions of the International School of Trigger and Data Acquisition (ISOTDAQ), the ISOTDAQ 2012 is the third of a series of this International School dedicated to introduce MSc and PhD students to the arts and crafts of triggering and acquiring data for physics experiments. The school will be held from 1 – 8 February 2012 in the Cracow University of Technology and Institute of Nuclear Physics, Cracow, Poland.  The school provides an up-to-date overview of the basic instruments and methodologies used in high energy physics, spanning from small experiences in lab to the very large LHC experiments, spotting the main building blocks as well as the different solutions and architectures at different levels of complexity. The main topics of the school include the basics of Data Acquisition (DAQ) programming concepts (e.g. threaded programming, data storage, networking, IO programming), hardware bus systems (VME bus, PCI), Trigger logic and Hardware (NIM). PC based readout...

  7. The first-level muon trigger system advances

    CERN Multimedia

    Ellis, N.

    2006-01-01

    Important advances have been made in the last few months in the first-level muon trigger, both for the barrel system and for the endcap system, in a close collaboration between the detector and trigger-electronics groups for the RPCs (Resistive-Plate Chambers) and TGCs (Thin-Gap Chambers). These trigger systems are crucial for the success of the muon-related physics programme of the experiment; events that are not triggered will be lost forever, and the trigger chambers also provide the second coordinate for the reconstruction of muons that are only measured in the bending plane by the MDT detectors. Integration and installation of the barrel muon trigger electronics on the RPC detectors is in full swing. The on-detector electronics consists of more than 800 units each of "Splitter" and "Pad" boxes which have been tested and integrated by a team of physicists, engineers and technicians from Italy and Romania. This work will continue for a further few months until the complete system has been installed and so...

  8. Where do we stand after twenty years of dynamic triggering studies? (Invited)

    Science.gov (United States)

    Prejean, S. G.; Hill, D. P.

    2013-12-01

    In the past two decades, remote dynamic triggering of earthquakes by other earthquakes has been explored in a variety of physical environments with a wide array of observation and modeling techniques. These studies have significantly refined our understanding of the state of the crust and the physical conditions controlling earthquake nucleation. Despite an ever growing database of dynamic triggering observations, significant uncertainties remain and vigorous debate in almost all aspects of the science continues. For example, although dynamic earthquake triggering can occur with peak dynamic stresses as small as 1 kPa, triggering thresholds and their dependence on local stress state, hydrological environment, and frictional properties of faults are not well understood. Some studies find a simple threshold based on the peak amplitude of shaking while others find dependencies on frequency, recharge time, and other parameters. Considerable debate remains over the range of physical processes responsible for dynamic triggering, and the wide variation in dynamic triggering responses and time scales suggests triggering by multiple physical processes. Although Coulomb shear failure with various friction laws can often explain dynamic triggering, particularly instantaneous triggering, delayed dynamic triggering may be dependent on fluid transport and other slowly evolving aseismic processes. Although our understanding of the global distribution of dynamic triggering has improved, it is far from complete due to spatially uneven monitoring. A major challenge involves establishing statistical significance of potentially triggered earthquakes, particularly if they are isolated events or time-delayed with respect to triggering stresses. Here we highlight these challenges and opportunities with existing data. We focus on environmental dependence of dynamic triggering by large remote earthquakes particularly in volcanic and geothermal systems, as these systems often have high

  9. Overview and performance of the ATLAS Level-1 Topological Trigger

    CERN Document Server

    Damp, Johannes Frederic; The ATLAS collaboration

    2018-01-01

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

  10. 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

  11. An FPGA-based trigger for the phase II of the MEG experiment

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, A. [Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Bemporad, C.; Cei, F. [Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Dipartimento di Fisica, Università di Pisa (Italy); Galli, L.; Grassi, M.; Morsani, F. [Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Nicolò, D., E-mail: donato.nicolo@pi.infn.it [Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Dipartimento di Fisica, Università di Pisa (Italy); Ritt, S. [Paul Scherrer Institut, Villigen AG (Switzerland); Venturini, M. [Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Scuola Normale Superiore, Pisa (Italy)

    2016-07-11

    For the phase II of MEG, we are going to develop a combined trigger and DAQ system. Here we focus on the former side, which operates an on-line reconstruction of detector signals and event selection within 450 μs from event occurrence. Trigger concentrator boards (TCB) are under development to gather data from different crates, each connected to a set of detector channels, to accomplish higher-level algorithms to issue a trigger in the case of a candidate signal event. We describe the major features of the new system, in comparison with phase I, as well as its performances in terms of selection efficiency and background rejection. - Highlights: • A new, two-level trigger scheme for the phase-II of the MEG experiment is presented. • Improvements with respect to phase-I are underlined. • The role of detector upgrades and the use of a new generation of FPGA as well are emphasized.

  12. A Fast Hardware Tracker for the ATLAS Trigger System

    CERN Document Server

    Neubauer, M; The ATLAS collaboration

    2011-01-01

    In hadron collider experiments, triggering the detector to store interesting events for offline analysis is a challenge due to the high rates and multiplicities of particles produced. The LHC will soon operate at a center-of-mass energy of 14 TeV and at high instantaneous luminosities of the order of $10^{34}$ to $10^{35}$ cm$^{-2}$ s$^{-1}$. A multi-level trigger strategy is used in ATLAS, with the first level (LVL1) implemented in hardware and the second and third levels (LVL2 and EF) implemented in a large computer farm. Maintaining high trigger efficiency for the physics we are most interested in while at the same time suppressing high rate physics from inclusive QCD processes is a difficult but important problem. It is essential that the trigger system be flexible and robust, with sufficient redundancy and operating margin. Providing high quality track reconstruction over the full ATLAS detector by the start of processing at LVL2 is an important element to achieve these needs. As the instantaneous lumino...

  13. LHC detectors trigger/DAQ at LHC

    CERN Document Server

    Sphicas, Paris

    1998-01-01

    At its design luminosity, the LHC will deliver hundreds of millions of proton-proton interactions per second. Storage and computing limitations limit the number of physics events that can be recorded to about 100 per second. The selection will be carried out by the Trigger and data acquisition systems of the experiments. This lecture will review the requirements, architectures and various designs currently considered.

  14. 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...

  15. ATLAS Tau Trigger

    CERN Document Server

    Belanger-Champagne, C; Bosman, M; Brenner, R; Casado, MP; Czyczula, Z; Dam, M; Demers, S; Farrington, S; Igonkina, O; Kalinowski, A; Kanaya, N; Osuna, C; Pérez, E; Ptacek, E; Reinsch, A; Saavedra, A; Sopczak, A; Strom, D; Torrence, E; Tsuno, S; Vorwerk, V; Watson, A; Xella, S

    2008-01-01

    Moving to the high energy scale of the LHC, the identification of tau leptons will become a necessary and very powerful tool, allowing a discovery of physics beyond Standard Model. Many models, among them light SM Higgs and various SUSY models, predict an abundant production of taus with respect to other leptons. The reconstruction of hadronic tau decays, although a very challenging task in hadronic enviroments, allows to increase a signal efficiency by at least of factor 2, and provides an independent control sample to disantangle lepton tau decays from prompt electrons and muons. Thanks to the advanced calorimetry and tracking, the ATLAS experiment has developed tools to efficiently identify hadronic taus at the trigger level. In this presentation we will review the characteristics of taus and the methods to suppress low-multiplicity, low-energy jets contributions as well as we will address the tau trigger chain which provide a rejection rate of 10^5. We will further present plans for commissioning the ATLA...

  16. 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 ...

  17. 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...

  18. 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 ...

  19. 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...

  20. The Physics Programme Of The MoEDAL Experiment At The LHC

    CERN Document Server

    Acharya, B.; Bernabeu, J.; Campbell, M.; Cecchini, S.; Chwastowski, J.; De Montigny, M.; Derendarz, D.; De Roeck, A.; Ellis, J.R.; Fairbairn, M.; Felea, D.; Frank, M.; Frekers, D.; Garcia, C.; Giacomelli, G.; Giorgini, M.; Hasegan, D.; Hott, T.; J.Jak\\r u; Katre, A.; Kim, D-W.; King, M.G.L.; Kinoshita, K.; Lacarrere, D.; Lee, S.C.; Leroy, C.; Margiotta, A.; Mauri, N.; Mavromatos, N.E.; Mermod, P.; Mitsou, V.A.; Orava, R.; Pasqualini, L.; Patrizii, L.; Pavalas, G.E.; Pinfold, J.L.; Platkevic, M.; Popa, V.; Pozzato, M.; Pospisil, S.; Rajantie, A.; Sahnoun, Z.; Sakellariadou, M.; Sarkar, S.; Semenoff, G.; Sirri, G.; Sliwa, K.; Soluk, R.; Spurio, M.; Srivastava, Y.N.; Staszewski, R.; Swain, J.; Tenti, M.; Togo, V.; Trzebinski, M.; Tuszynski, J.A.; Vento, V.; Vives, O.; Vykydal, Z.; Widom, A.; Yoon, J.H.

    2014-01-01

    The MoEDAL experiment at Point 8 of the LHC ring is the seventh and newest LHC experiment. It is dedicated to the search for highly ionizing particle avatars of physics beyond the Standard Model, extending significantly the discovery horizon of the LHC. A MoEDAL discovery would have revolutionary implications for our fundamental understanding of the Microcosm. MoEDAL is an unconventional and largely passive LHC detector comprised of the largest array of Nuclear Track Detector stacks ever deployed at an accelerator, surrounding the intersection region at Point 8 on the LHC ring. Another novel feature is the use of paramagnetic trapping volumes to capture both electrically and magnetically charged highly-ionizing particles predicted in new physics scenarios. It includes an array of TimePix pixel devices for monitoring highly-ionizing particle backgrounds. The main passive elements of the MoEDAL detector do not require a trigger system, electronic readout, or online computerized data acquisition. The aim of this...

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

    CERN Document Server

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

    2015-01-01

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

  2. Experiments in physical chemistry

    CERN Document Server

    Wilson, J M; Denaro, A R

    1968-01-01

    Experiments in Physical Chemistry, Second Edition provides a compilation of experiments concerning physical chemistry. This book illustrates the link between the theory and practice of physical chemistry. Organized into three parts, this edition begins with an overview of those experiments that generally have a simple theoretical background. Part II contains experiments that are associated with more advanced theory or more developed techniques, or which require a greater degree of experimental skill. Part III consists of experiments that are in the nature of investigations wherein these invest

  3. 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

  4. 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...

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

    CERN Document Server

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

    2004-01-01

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

  6. 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.

  7. 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...

  8. A first level trigger approach for the CBM experiment

    International Nuclear Information System (INIS)

    Steinle, Christian Alexander

    2012-01-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly considered in the

  9. A first level trigger approach for the CBM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steinle, Christian Alexander

    2012-07-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly

  10. A first level trigger approach for the CBM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steinle, Christian Alexander

    2012-07-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly considered in the

  11. The Phase-1 Upgrade for the Level-1 Muon Barrel Trigger of the ATLAS Experiment at LHC

    CERN Document Server

    Izzo, Vincenzo; The ATLAS collaboration

    2018-01-01

    The Level-1 Muon Barrel Trigger of the ATLAS Experiment at LHC makes use of Resistive Plate Chamber (RPC) detectors. The on-detector trigger electronics modules are able to identify muons with predefined transverse momentum values (pT) by executing a coincidence logic on signals coming from the various detector layers. On-detector trigger boards then transfer trigger data to the off-detector electronics. A complex trigger system processes the incoming data by combining trigger information from the barrel and the endcap regions, and providing the combined muon candidate to the Central Trigger Processor (CTP). For almost a decade, the Level-1 Trigger system operated very well, despite the challenging requirements on trigger efficiency and performance, and the continuously increasing LHC luminosity. In order to cope with these constraints, various upgrades for the full trigger system were already deployed, and others have been designed to be installed in the next years. Most of the upgrades to the trigger system...

  12. Results from a MA16-based neural trigger in an experiment looking for beauty

    International Nuclear Information System (INIS)

    Baldanza, C.; Beichter, J.; Bisi, F.; Bruels, N.; Bruschini, C.; Cotta-Ramusino, A.; D'Antone, I.; Malferrari, L.; Mazzanti, P.; Musico, P.; Novelli, P.; Odorici, F.; Odorico, R.; Passaseo, M.; Zuffa, M.

    1996-01-01

    Results from a neural-network trigger based on the digital MA16 chip of Siemens are reported. The neural trigger has been applied to data from the WA92 experiment, looking for beauty particles, which have been collected during a run in which a neural trigger module based on Intel's analog neural chip ETANN operated, as already reported. The MA16 board hosting the chip has a 16-bit I/O precision and a 53-bit precision for internal calculations. It operated at 50 MHz, yielding a response time for a 16 input-variable net of 3 μs for a Fisher discriminant (1-layer net) and of 6 μs for a 2-layer net. Results are compared with those previously obtained with the ETANN trigger. (orig.)

  13. Results from a MA16-based neural trigger in an experiment looking for beauty

    Energy Technology Data Exchange (ETDEWEB)

    Baldanza, C. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Beichter, J. [Siemens AG, ZFE T ME2, 81730 Munich (Germany); Bisi, F. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Bruels, N. [Siemens AG, ZFE T ME2, 81730 Munich (Germany); Bruschini, C. [INFN/Genoa, Via Dodecaneso 33, 16146 Genoa (Italy); Cotta-Ramusino, A. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); D`Antone, I. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Malferrari, L. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Mazzanti, P. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Musico, P. [INFN/Genoa, Via Dodecaneso 33, 16146 Genoa (Italy); Novelli, P. [INFN/Genoa, Via Dodecaneso 33, 16146 Genoa (Italy); Odorici, F. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Odorico, R. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Passaseo, M. [CERN, 1211 Geneva 23 (Switzerland); Zuffa, M. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy)

    1996-07-11

    Results from a neural-network trigger based on the digital MA16 chip of Siemens are reported. The neural trigger has been applied to data from the WA92 experiment, looking for beauty particles, which have been collected during a run in which a neural trigger module based on Intel`s analog neural chip ETANN operated, as already reported. The MA16 board hosting the chip has a 16-bit I/O precision and a 53-bit precision for internal calculations. It operated at 50 MHz, yielding a response time for a 16 input-variable net of 3 {mu}s for a Fisher discriminant (1-layer net) and of 6 {mu}s for a 2-layer net. Results are compared with those previously obtained with the ETANN trigger. (orig.).

  14. Data Driven Trigger Design and Analysis for the NOvA Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kurbanov, Serdar [Univ. of Virginia, Charlottesville, VA (United States)

    2016-01-01

    This thesis primarily describes analysis related to studying the Moon shadow with cosmic rays, an analysis using upward-going muons trigger data, and other work done as part of MSc thesis work conducted at Fermi National Laboratory. While at Fermilab I made hardware and software contributions to two experiments - NOvA and Mu2e. NOvA is a neutrino experiment with the primary goal of measuring parameters related to neutrino oscillation. This is a running experiment, so it's possible to provide analysis of real beam and cosmic data. Most of this work was related to the Data-Driven Trigger (DDT) system of NOvA. The results of the Upward-Going muon analysis was presented at ICHEP in August 2016. The analysis demonstrates the proof of principle for a low-mass dark matter search. Mu2e is an experiment currently being built at Fermilab. Its primary goal is to detect the hypothetical neutrinoless conversion from a muon into an electron. I contributed to the production and tests of Cathode Strip Chambers (CSCs) which are required for testing the Cosmic Ray Veto (CRV) system for the experiment. This contribution is described in the last chapter along with a short description of the technical work provided for the DDT system of the NOvA experiment. All of the work described in this thesis will be extended by the next generation of UVA graduate students and postdocs as new data is collected by the experiment. I hope my eorts of have helped lay the foundation for many years of beautiful results from Mu2e and NOvA.

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

    CERN Document Server

    Boisvert, V; The ATLAS collaboration

    2012-01-01

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

  16. Performance of the ATLAS Tau Trigger system with 7 TeV pp collisions at the LHC

    CERN Document Server

    Xella, S; The ATLAS collaboration

    2011-01-01

    The LHC has started operation and roughly provided 60 nb$^{-1}$ of 7 TeV proton-proton collisions in the period March-June 2010. These data have been used to understand the performance of the ATLAS experiment, and in particular, of the tau trigger system. The tau trigger is a key element in the discovery of new physics, where tau lepton final states play a crucial role. It allows efficient collection of the physics signal, while keeping the rate of background events within the allowed bandwidth. During 2010 it has been commissioned in various stages. At first, the hardware-based first level trigger (L1) was used to select interesting high p$_{T}$ physics samples. During this period the Higher Level Trigger (HLT) was running online, but not rejecting any events. This stage has allowed to study in detail the HLT performance before activation. At a later time, when the luminosity was high enough that the L1 trigger alone could not reject anymore events without affecting the collection of interesting physics, the...

  17. 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...

  18. Level 3 trigger algorithm and hardware platform for the HADES experiment

    International Nuclear Information System (INIS)

    Kirschner, Daniel Georg

    2007-01-01

    One focus of the HADES experiment is the investigation of the decay of light vector mesons inside a dense medium into lepton pairs. These decays provide a conceptually ideal tool to study the invariant mass of the vector meson in-medium, since the lepton pairs of these meson decays leave the reaction without further strong interaction. Thus, no final state interaction affects the measurement. Unfortunately, the branching ratios of vector mesons into lepton pairs are very small (∼ 10 -5 ). This calls for a high rate, high acceptance experiment. In addition, a sophisticated real time trigger system is used in HADES to enrich the interesting events in the recorded data. The focus of this thesis is the development of a next generation real time trigger method to improve the enrichment of lepton events in the HADES trigger. In addition, a flexible hardware platform (GE-MN) was developed to implement and test the trigger method. The GE-MN features two Gigabit-Ethernet interfaces for data transport, a VMEbus for slow control and configuration, and a TigerSHARC DSP for data processing. It provides the experience to discuss the challenges and benefits of using a commercial standard network technology based system in an experiment. The developed and tested trigger method correlates the ring information of the HADES RICH with the fired wires (cells) of the HADES MDC detector. This correlation method operates by calculating for each event the cells which should have seen the signal of a traversing lepton, and compares these calculated cells to all the cells that did see a signal. The cells which should have fired are calculated from the polar and azimuthal angle information of the RICH rings by assuming a straight line in space, which is starting at the target and extending into a direction given by the ring angles. The line extends through the inner MDC chambers and the traversed cells are those that should have been hit. To compensate different sources for inaccuracies not

  19. Level 3 trigger algorithm and hardware platform for the HADES experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kirschner, Daniel Georg

    2007-10-26

    One focus of the HADES experiment is the investigation of the decay of light vector mesons inside a dense medium into lepton pairs. These decays provide a conceptually ideal tool to study the invariant mass of the vector meson in-medium, since the lepton pairs of these meson decays leave the reaction without further strong interaction. Thus, no final state interaction affects the measurement. Unfortunately, the branching ratios of vector mesons into lepton pairs are very small ({approx} 10{sup -5}). This calls for a high rate, high acceptance experiment. In addition, a sophisticated real time trigger system is used in HADES to enrich the interesting events in the recorded data. The focus of this thesis is the development of a next generation real time trigger method to improve the enrichment of lepton events in the HADES trigger. In addition, a flexible hardware platform (GE-MN) was developed to implement and test the trigger method. The GE-MN features two Gigabit-Ethernet interfaces for data transport, a VMEbus for slow control and configuration, and a TigerSHARC DSP for data processing. It provides the experience to discuss the challenges and benefits of using a commercial standard network technology based system in an experiment. The developed and tested trigger method correlates the ring information of the HADES RICH with the fired wires (cells) of the HADES MDC detector. This correlation method operates by calculating for each event the cells which should have seen the signal of a traversing lepton, and compares these calculated cells to all the cells that did see a signal. The cells which should have fired are calculated from the polar and azimuthal angle information of the RICH rings by assuming a straight line in space, which is starting at the target and extending into a direction given by the ring angles. The line extends through the inner MDC chambers and the traversed cells are those that should have been hit. To compensate different sources for

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

    CERN Document Server

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

    2017-01-01

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

  1. Implementation and synchronisation of the First Level Global Trigger for the CMS experiment at LHC

    International Nuclear Information System (INIS)

    Taurok, A.; Bergauer, H.; Padrta, M.

    2001-01-01

    The hardware implementation of the First Level Global Trigger for the Compact Muon Solenoid experiment at the CERN Large Hadron Collider is described. Special emphasis is given to the algorithm logic and the synchronisation procedure. Up to 128 different trigger algorithms are calculated in parallel by the Global Trigger (GT) for every beam crossing taking place at 25 ns intervals. Already, at the first trigger level the GT is able to select complex topological event configurations by performing fast calculations. The electronics is based on VME and relies completely on Field Programmable Gate Arrays (FPGA) technology. The electronic circuits are optimised for speed by exploiting, to a great extent, the small look-up tables provided in the FPGA chips

  2. The Phase-1 Upgrade for the Level-1 Muon Barrel Trigger of the ATLAS Experiment at LHC

    CERN Document Server

    Izzo, Vincenzo; The ATLAS collaboration

    2018-01-01

    The Level-1 Barrel Trigger of the ATLAS Experiment is based on Resistive Plate Chambers (RPC) detectors. The on-detector trigger electronics identifies muons with specific values of transverse momentum (pT), by using coincidences between different layers of detectors. Trigger data is then transferred from on-detector to the off-detector trigger electronics boards. Data is processed by a complex system, which combines trigger data from the Barrel and the End-cap regions, and provides the combined muon candidate to the Central Trigger Processor (CTP). The system has been performing very well for almost a decade. However, in order to cope with continuously increasing LHC luminosity and more demanding requirements on trigger efficiency and performance, various upgrades for the full trigger system were already deployed, and others are foreseen in the next years. Most of the trigger upgrades are based on state-of-the-art technologies and allow designing more complex trigger menus, increasing processing power and da...

  3. The Phase-1 Upgrade for the Level-1 Muon Barrel Trigger of the ATLAS Experiment at LHC

    CERN Document Server

    Izzo, Vincenzo; The ATLAS collaboration

    2018-01-01

    The Level-1 Muon Barrel Trigger of the ATLAS Experiment at LHC makes use of Resistive Plate Chamber (RPC) detectors. The on-detector trigger electronics modules are able to identify muons with predefined transverse momentum values (pT) by executing a coincidence logic on signals coming from the various detector layers. Then, on-detector trigger boards transfer trigger data to the off-detector electronics. A complex trigger system processes the incoming data by combining trigger information from the Barrel and the End-cap regions, and by providing the combined muon candidate to the Central Trigger Processor (CTP). For almost a decade, the Level-1 Trigger system has been operating very well, despite the challenging requirements on trigger efficiency and performance, and the continuously increasing LHC luminosity. In order to cope with these constraints, various upgrades for the full trigger system were already deployed, and others have been designed to be installed in the next years. Most of the upgrades to the...

  4. 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.

  5. JACoW Configuring and automating an LHC experiment for faster and better physics output

    CERN Document Server

    Gaspar, Clara; Alessio, Federico; Barbosa, Joao; Cardoso, Luis; Frank, Markus; Jost, Beat; Neufeld, Niko; Schwemmer, Rainer

    2018-01-01

    LHCb has introduced a novel online detector alignment and calibration for LHC Run II. This strategy allows for better trigger efficiency, better data quality and direct physics analysis at the trigger output. This implies: running a first High Level Trigger (HLT) pass synchronously with data taking and buffering locally its output; use the data collected at the beginning of the fill, or on a run-by-run basis, to determine the new alignment and calibration constants; run a second HLT pass on the buffered data using the new constants. Operationally, it represented a challenge: it required running different activities concurrently in the farm, starting at different times and load balanced depending on the LHC state. However, these activities are now an integral part of LHCb's dataflow, seamlessly integrated in the Experiment Control System and completely automated under the supervision of LHCb's 'Big Brother'. In total, for all activities, there are usually around 60000 tasks running in the ~1600 nodes of the fa...

  6. Development of a digital trigger system to identify recoil protons at COMPASS-II

    Energy Technology Data Exchange (ETDEWEB)

    Buechele, Maximilian; Fischer, Horst; Gorzellik, Matthias; Grussenmeyer, Tobias; Herrmann, Florian; Joerg, Philipp; Koenigsmann, Kay; Kremser, Paul; Schopferer, Sebastian [Albert-Ludwigs-Universitaet Freiburg (Germany)

    2014-07-01

    The GANDALF framework has been developed to deliver a high precision, high performance detector readout and trigger system for particle physics experiments such as the COMPASS-II experiment at CERN. Combining the high performance pulse digitization and feature extraction capabilities of twelve GANDALF modules, each comprising a Virtex-5 SX95T, with the strong computation power of a Virtex-6 SX315T FGPA operated on the TIGER module, we present a digital trigger system for a recoil proton detector. The trigger system was setup and commissioned successfully during a data taking period in 2012. It was mainly used for the calibration of the recoil proton detector and in tagging mode to identify proton tracks online.

  7. 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.

  8. ATLAS Level-1 Topological Trigger

    CERN Document Server

    Zheng, Daniel; The ATLAS collaboration

    2018-01-01

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

  9. 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 ...

  10. An on-line non-leptonic neural trigger applied to an experiment looking for beauty

    CERN Document Server

    Baldanza, C; Cotta-Ramusino, A; D'Antone, I; Malferrari, L; Mazzanti, P; Odorici, F; Odorico, R; Zuffa, M; Bruschini, C; Musico, P; Novelli, P; Passaseo, M

    1994-01-01

    Results from a non-leptonic neural-network trigger hosted by experiment WA92, looking for beauty particle production from 350 GeV 1t- on a Cu target, are presented. The neural trigger has been used to send on a special data stream (the Fast Stream) events to be analyzed with high priority. The non-leptonic signature uses microvertex detector data and was devised so as to enrich the fraction of events containing C3 secondary vertices (i.e, vertices having three tracks whith sum of electric charges equal to +1 or -1). The neural trigger module consists of a VME crate hosting two ET ANN analog neural chips from Intel. The neural trigger operated for two continuous weeks during the WA92 1 993 run. For an acceptance of 15% for C3 events, the neural trigger yields a C3 enrichment factor of 6.6-7.l (depending on the event sample considered), which multiplied by that already provided by the standard non-leptonic trigger leads to a global C3 enrichment factor of -1 50. In the event sample selected by the neural trigge...

  11. 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.

  12. 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.

  13. Simulation and Validation of the ATLAS Level-1 Topological Trigger

    CERN Document Server

    Bakker, Pepijn Johannes; The ATLAS collaboration

    2017-01-01

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

  14. High level trigger system for the ALICE experiment

    International Nuclear Information System (INIS)

    Frankenfeld, U.; Roehrich, D.; Ullaland, K.; Vestabo, A.; Helstrup, H.; Lien, J.; Lindenstruth, V.; Schulz, M.; Steinbeck, T.; Wiebalck, A.; Skaali, B.

    2001-01-01

    The ALICE experiment at the Large Hadron Collider (LHC) at CERN will detect up to 20,000 particles in a single Pb-Pb event resulting in a data rate of ∼75 MByte/event. The event rate is limited by the bandwidth of the data storage system. Higher rates are possible by selecting interesting events and subevents (High Level trigger) or compressing the data efficiently with modeling techniques. Both require a fast parallel pattern recognition. One possible solution to process the detector data at such rates is a farm of clustered SMP nodes, based on off-the-shelf PCs, and connected by a high bandwidth, low latency network

  15. 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

  16. Therapeutic-Ultrasound-Triggered Shape Memory of a Melamine-Enhanced Poly(vinyl alcohol) Physical Hydrogel.

    Science.gov (United States)

    Li, Guo; Yan, Qiang; Xia, Hesheng; Zhao, Yue

    2015-06-10

    Therapeutic-ultrasound-triggered shape memory was demonstrated for the first time with a melamine-enhanced poly(vinyl alcohol) (PVA) physical hydrogel. The addition of a small amount of melamine (up to 1.5 wt %) in PVA results in a strong hydrogel due to the multiple H-bonding between the two constituents. A temporary shape of the hydrogel can be obtained by deformation of the hydrogel (∼65 wt % water) at room temperature, followed by fixation of the deformation by freezing/thawing the hydrogel under strain, which induces crystallization of PVA. We show that the ultrasound delivered by a commercially available device designed for the patient's pain relief could trigger the shape recovery process as a result of ultrasound-induced local heating in the hydrogel that melts the crystallized PVA cross-linking. This hydrogel is thus interesting for potential applications because it combines many desirable properties, being mechanically strong, biocompatible, and self-healable and displaying the shape memory capability triggered by a physiological stimulus.

  17. The CMS Trigger Supervisor: Control and Hardware Monitoring System of the CMS Level-1 Trigger at CERN

    CERN Document Server

    Ildefons Magrans de Abril

    2008-01-01

    The experiments CMS (Compact Muon Solenoid) and ATLAS (A Toroidal LHC ApparatuS) at the LargeHadron Collider (LHC) are the greatest exponents of the rising complexity in High Energy Physics (HEP) datahandling instrumentation. Tens of millions of readout channels, tens of thousands of hardware boards and thesame order of connections are figures of merit. However, the hardware volume is not the only complexitydimension, the unprecedented large number of research institutes and scientists that form the internationalcollaborations, and the long design, development, commissioning and operational phases are additional factorsthat must be taken into account.The Level-1 (L1) trigger decision loop is an excellent example of these difficulties. This system is based on apipelined logic destined to analyze without deadtime the data from each LHC bunch crossing occurring every25_ns, using special coarsely segmented trigger data from the detectors. The L1 trigger is responsible forreducing the rate of accepted crossings to...

  18. A T0/Trigger detector for the External Target Experiment at CSR

    Science.gov (United States)

    Hu, D.; Shao, M.; Sun, Y.; Li, C.; Chen, H.; Tang, Z.; Zhang, Y.; Zhou, J.; Zeng, H.; Zhao, X.; You, W.; Song, G.; Deng, P.; Lu, J.; Zhao, L.

    2017-06-01

    A new T0/Trigger detector based on multi-gap resistive plate chamber (MRPC) technology has been constructed and tested for the external target experiment (ETE) at HIRFL-CSR. It measures the multiplicity and timing information of particles produced in heavy-ion collisions at the target region, providing necessary event collision time (T0) and collision centrality with high precision. Monte-Carlo simulation shows a time resolution of several tens of picosecond can be achieved at central collisions. The experimental tests have been performed for this prototype detector at the CSR-ETE. The preliminary results are shown to demonstrate the performance of the T0/Trigger detector.

  19. Physical experience enhances science learning.

    Science.gov (United States)

    Kontra, Carly; Lyons, Daniel J; Fischer, Susan M; Beilock, Sian L

    2015-06-01

    Three laboratory experiments involving students' behavior and brain imaging and one randomized field experiment in a college physics class explored the importance of physical experience in science learning. We reasoned that students' understanding of science concepts such as torque and angular momentum is aided by activation of sensorimotor brain systems that add kinetic detail and meaning to students' thinking. We tested whether physical experience with angular momentum increases involvement of sensorimotor brain systems during students' subsequent reasoning and whether this involvement aids their understanding. The physical experience, a brief exposure to forces associated with angular momentum, significantly improved quiz scores. Moreover, improved performance was explained by activation of sensorimotor brain regions when students later reasoned about angular momentum. This finding specifies a mechanism underlying the value of physical experience in science education and leads the way for classroom practices in which experience with the physical world is an integral part of learning. © The Author(s) 2015.

  20. Trigger electronics of the new Fluorescence Detectors of the Telescope Array Experiment

    International Nuclear Information System (INIS)

    Tameda, Yuichiro; Taketa, Akimichi; Smith, Jeremy D.; Tanaka, Manobu; Fukushima, Masaki; Jui, Charles C.H.; Kadota, Ken'ichi; Kakimoto, Fumio; Matsuda, Takeshi; Matthews, John N.; Ogio, Shoichi; Sagawa, Hiroyuki; Sakurai, Nobuyuki; Shibata, Tatsunobu; Takeda, Masahiro; Thomas, Stanton B.; Tokuno, Hisao; Tsunesada, Yoshiki

    2009-01-01

    The Telescope Array Project is an experiment designed to observe Ultra High Energy Cosmic Rays via a 'hybrid' detection technique utilizing both fluorescence light detectors (FDs) and scintillator surface particle detectors (SDs). We have installed three FD stations and 507 SDs in the Utah desert, and initiated observations from March 2008. The northern FD station reuses 14 telescopes from the High Resolution Fly's Eye, HiRes-I station. Each of the two southern FD stations contains 12 new telescopes utilizing new FADC electronics. Each telescope is instrumented with a camera composed of 256 PMTs. Since the detectors are composed of many PMTs and each PMT detects fluorescence photons together with the vast amount of night sky background, a sophisticated triggering system is required. In this paper, we describe the trigger electronics of these new FD stations. We also discuss performance of the FDs with this triggering system, in terms of efficiencies and apertures for various detector configurations.

  1. Role of physical bolus properties as sensory inputs in the trigger of swallowing.

    Science.gov (United States)

    Peyron, Marie-Agnès; Gierczynski, Isabelle; Hartmann, Christoph; Loret, Chrystel; Dardevet, Dominique; Martin, Nathalie; Woda, Alain

    2011-01-01

    Swallowing is triggered when a food bolus being prepared by mastication has reached a defined state. However, although this view is consensual and well supported, the physical properties of the swallowable bolus have been under-researched. We tested the hypothesis that measuring bolus physical changes during the masticatory sequence to deglutition would reveal the bolus properties potentially involved in swallowing initiation. Twenty normo-dentate young adults were instructed to chew portions of cereal and spit out the boluses at different times in the masticatory sequence. The mechanical properties of the collected boluses were measured by a texture profile analysis test currently used in food science. The median particle size of the boluses was evaluated by sieving. In a simultaneous sensory study, twenty-five other subjects expressed their perception of bolus texture dominating at any mastication time. Several physical changes appeared in the food bolus as it was formed during mastication: (1) in rheological terms, bolus hardness rapidly decreased as the masticatory sequence progressed, (2) by contrast, adhesiveness, springiness and cohesiveness regularly increased until the time of swallowing, (3) median particle size, indicating the bolus particle size distribution, decreased mostly during the first third of the masticatory sequence, (4) except for hardness, the rheological changes still appeared in the boluses collected just before swallowing, and (5) physical changes occurred, with sensory stickiness being described by the subjects as a dominant perception of the bolus at the end of mastication. Although these physical and sensory changes progressed in the course of mastication, those observed just before swallowing seem to be involved in swallowing initiation. They can be considered as strong candidates for sensory inputs from the bolus that are probably crucially involved in the triggering of swallowing, since they appeared in boluses prepared in various

  2. Role of physical bolus properties as sensory inputs in the trigger of swallowing.

    Directory of Open Access Journals (Sweden)

    Marie-Agnès Peyron

    Full Text Available BACKGROUND: Swallowing is triggered when a food bolus being prepared by mastication has reached a defined state. However, although this view is consensual and well supported, the physical properties of the swallowable bolus have been under-researched. We tested the hypothesis that measuring bolus physical changes during the masticatory sequence to deglutition would reveal the bolus properties potentially involved in swallowing initiation. METHODS: Twenty normo-dentate young adults were instructed to chew portions of cereal and spit out the boluses at different times in the masticatory sequence. The mechanical properties of the collected boluses were measured by a texture profile analysis test currently used in food science. The median particle size of the boluses was evaluated by sieving. In a simultaneous sensory study, twenty-five other subjects expressed their perception of bolus texture dominating at any mastication time. FINDINGS: Several physical changes appeared in the food bolus as it was formed during mastication: (1 in rheological terms, bolus hardness rapidly decreased as the masticatory sequence progressed, (2 by contrast, adhesiveness, springiness and cohesiveness regularly increased until the time of swallowing, (3 median particle size, indicating the bolus particle size distribution, decreased mostly during the first third of the masticatory sequence, (4 except for hardness, the rheological changes still appeared in the boluses collected just before swallowing, and (5 physical changes occurred, with sensory stickiness being described by the subjects as a dominant perception of the bolus at the end of mastication. CONCLUSIONS: Although these physical and sensory changes progressed in the course of mastication, those observed just before swallowing seem to be involved in swallowing initiation. They can be considered as strong candidates for sensory inputs from the bolus that are probably crucially involved in the triggering of

  3. A Fast hardware tracker for the ATLAS Trigger

    CERN Document Server

    Pandini, Carlo Enrico; The ATLAS collaboration

    2015-01-01

    The trigger system at the ATLAS experiment is designed to lower the event rate occurring from the nominal bunch crossing at 40 MHz to about 1 kHz for a designed LHC luminosity of 10$^{34}$ cm$^{-2}$ s$^{-1}$. To achieve high background rejection while maintaining good efficiency for interesting physics signals, sophisticated algorithms are needed which require extensive use of tracking information. The Fast TracKer (FTK) trigger system, part of the ATLAS trigger upgrade program, is a highly parallel hardware device designed to perform track-finding at 100 kHz and based on a mixture of advanced technologies. Modern, powerful Field Programmable Gate Arrays (FPGA) form an important part of the system architecture, and the combinatorial problem of pattern recognition is solved by ~8000 standard-cell ASICs named Associative Memories. The availability of the tracking and subsequent vertex information within a short latency ensures robust selections and allows improved trigger performance for the most difficult sign...

  4. 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

  5. Particle physics experiments

    International Nuclear Information System (INIS)

    Stuart, G.W.

    1986-01-01

    The report of the Rutherford Appleton Laboratory describes the work carried out in 1985 on experiments approved by the Particle Physics Experiments Selection Panel. The contents consist of unedited contributions from each experiment. (author)

  6. PHYSICS

    CERN Multimedia

    J. Incandela

    There have been numerous developments in the physics area since the September CMS week. The biggest single event was the Physics/Trigger week in the end of Octo¬ber, whereas in terms of ongoing activities the “2007 analyses” went into high gear. This was in parallel with participation in CSA07 by the physics groups. On the or¬ganizational side, the new conveners of the physics groups have been selected, and a new database for man¬aging physics analyses has been deployed. Physics/Trigger week The second Physics-Trigger week of 2007 took place during the week of October 22-26. The first half of the week was dedicated to working group meetings. The ple¬nary Joint Physics-Trigger meeting took place on Wednesday afternoon and focused on the activities of the new Trigger Studies Group (TSG) and trigger monitoring. Both the Physics and Trigger organizations are now focused on readiness for early data-taking. Thus, early trigger tables and preparations for calibr...

  7. Modelling of local/global architectures for second level trigger at the LHC experiment

    International Nuclear Information System (INIS)

    Hajduk, Z.; Iwanski, W.; Korecyl, K.; Strong, J.

    1994-01-01

    Different architectures of the second level triggering system for experiments on LHC have been simulated. The basic scheme was local/global system with distributed computing power. As a tool the authors have used the object-oriented MODSIM II language

  8. 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

  9. 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.

  10. The TIGER trigger processor for the CAMERA detector at COMPASS-II

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Tobias; Buechele, Maximilian; Fischer, Horst; Gorzellik, Matthias; Grussenmeyer, Tobias; Herrmann, Florian; Joerg, Philipp; Kremser, Paul; Kunz, Tobias; Michalski, Christoph; Schopferer, Sebastian; Szameitat, Tobias [Physikalisches Institut der Universitaet Freiburg, Freiburg im Breisgau (Germany)

    2013-07-01

    In today's nuclear and high-energy physics experiments the background-induced occupancy of the detector channels can be quite high; therefore it is important to have sophisticated trigger subsystems which process the data in real-time to generate trigger objects for the global trigger decision. In this work we present a FPGA based low-latency trigger processor for the COMPASS-II experiment. TIGER is a high-performance trigger processor that was developed to fit perfectly in the GANDALF framework and extend its versatility. It is designed as a VXS module and is allocated to the central VXS switch slot, which has a direct link from every payload slot. The synchronous transfer protocol was optimized for low latencies and offers a bandwidth of up to 8 Gbit/s per link. The centerpiece of the board is a Xilinx Virtex-6 SX315T FPGA, offering vast programmable logic, embedded memory and DSP resources. It is accompanied by DDR3 memory, a COM Express CPU and a MXM GPU. Besides the VXS backplane ports, the board features two SFP+ transceivers, 32 LVDS inputs and 32 LVDS outputs to interface with the global trigger system and a Gigabit Ethernet port for configuration and monitoring.

  11. 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...

  12. The fastbus trigger modules for the SAT detector in the DELPHI experiment at LEP, CERN

    International Nuclear Information System (INIS)

    Alvsvaag, S.J.

    1992-09-01

    This thesis describes the functionality and performance of the fastbus trigger modules for the Small Angle Tagger (SAT) detector in the DELPHI experiment at the LEP machine at CERN. The main purpose of the modules is to provide a Bhabha trigger for the SAT calorimeter used for luminosity measurements. The author has bee responsible for the design, production, testing and installation of the trigger modules. All the test programs necessary to confirm that the modules function according to the specifications are included in this work. Is does not, however, aim to make detailed technical descriptions of the modules. 44 refs., 39 figs., 18 tabs

  13. 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.

  14. 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.

  15. A proposed DT-seeded Muon Track Trigger for the HL-LHC

    CERN Document Server

    CMS Collaboration

    2015-01-01

    The LHC program after the observation of the candidate SM Higgs boson will continue with collisions at 13 and 14 TeV, which will help clarify future subjects of study and shape the tools needed to carry them on. Any upgrade of the LHC experiments for unprecedented luminosities, such as the HL-LHC ones, must then maintain the acceptance on electroweak processes that can lead to a detailed study of the properties of the candidate Higgs boson. The acceptance of the key leptonic, photonic and hadronic trigger objects should be kept such that the overall physics acceptance, in particular for low-mass scale processes, can be the same as the one the experiments featured in 2012. In such a scenario, a new approach to early trigger implementation is needed. One of the major steps to be taken is the exploitation of high-granularity tracking sub-detectors, such as the CMS Silicon Tracker, in taking the early trigger decision. Their inclusion into the trigger chain can be crucial in several tasks, including the confirmat...

  16. Realization of a second level neural network trigger for the H1 experiment at HERA

    International Nuclear Information System (INIS)

    Koehne, J.K.; Fent, J.; Froechtenicht, W.; Gaede, F.; Gruber, A.; Haberer, W.; Kiesling, C.; Kobler, T.; Moeck, J.; Wegner, A.; Goldner, D.; Kraemerkaemper, T.; Kolander, M.; Kolanoski, H.

    1997-01-01

    Since 1996 the H1 experiment is fully equipped with two independent fast pattern recognition systems operating as second level triggers (L2). The decision time is 20 μs. One of the two is the neural network trigger. It runs an array of presently ten VME-boards with CNAPS 1064 chips (20 MHz, 128 Mcps) by adaptive solutions. The input trigger data from the detector components arrive in various formats on a 8 x 16 bit wide 10 MHz bus. Before usable as 8-bit input values to the CNAPS they are preprocessed by several bit-manipulating algorithms and arithmetic functions implemented on XILINX 4008 field programmable gate arrays (FPGA). The startup strategy for the new system is to concentrate on photoproduction channels or low multiplicity final states which so far could only be efficiently triggered with unacceptable high rates. (orig.)

  17. Evolution of the Trigger and Data Acquisition System for the ATLAS experiment

    CERN Document Server

    Negri, A; The ATLAS collaboration

    2012-01-01

    The ATLAS experiment at the Large Hadron Collider at CERN relies on a complex and highly distributed Trigger and Data Acquisition (TDAQ) system to gather and select particle collision data at unprecedented energy and rates. The TDAQ is composed of three levels which reduces the event rate from the design bunch-crossing rate of 40 MHz to an average event recording rate of about 200 Hz. The first part of this paper gives an overview of the operational performance of the DAQ system during 2011 and the first months of data taking in 2012. It describes how the flexibility inherent in the design of the system has be exploited to meet the changing needs of ATLAS data taking and in some cases push performance beyond the original design performance specification. The experience accumulated in the TDAQ system operation during these years stimulated also 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), ...

  18. Graphics Processors in HEP Low-Level Trigger Systems

    International Nuclear Information System (INIS)

    Ammendola, Roberto; Biagioni, Andrea; Chiozzi, Stefano; Ramusino, Angelo Cotta; Cretaro, Paolo; Lorenzo, Stefano Di; Fantechi, Riccardo; Fiorini, Massimiliano; Frezza, Ottorino; Lamanna, Gianluca; Cicero, Francesca Lo; Lonardo, Alessandro; Martinelli, Michele; Neri, Ilaria; Paolucci, Pier Stanislao; Pastorelli, Elena; Piandani, Roberto; Pontisso, Luca; Rossetti, Davide; Simula, Francesco; Sozzi, Marco; Vicini, Piero

    2016-01-01

    Usage of Graphics Processing Units (GPUs) in the so called general-purpose computing is emerging as an effective approach in several fields of science, although so far applications have been employing GPUs typically for offline computations. Taking into account the steady performance increase of GPU architectures in terms of computing power and I/O capacity, the real-time applications of these devices can thrive in high-energy physics data acquisition and trigger systems. We will examine the use of online parallel computing on GPUs for the synchronous low-level trigger, focusing on tests performed on the trigger system of the CERN NA62 experiment. To successfully integrate GPUs in such an online environment, latencies of all components need analysing, networking being the most critical. To keep it under control, we envisioned NaNet, an FPGA-based PCIe Network Interface Card (NIC) enabling GPUDirect connection. Furthermore, it is assessed how specific trigger algorithms can be parallelized and thus benefit from a GPU implementation, in terms of increased execution speed. Such improvements are particularly relevant for the foreseen Large Hadron Collider (LHC) luminosity upgrade where highly selective algorithms will be essential to maintain sustainable trigger rates with very high pileup

  19. 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...

  20. 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

  1. The CMS experiment puts physics onto the menu

    CERN Document Server

    Leonidopoulos, Christos

    2011-01-01

    CMS has addressed the challenge of identifying in real time different kinds of 
physics at the LHC – from the "bread and butter" of Standard Model processes to 
signals of new particles – with triggers served up according to a carefully designed menu.

  2. Destructive electronics from electrochemical-mechanically triggered chemical dissolution

    International Nuclear Information System (INIS)

    Sim, Kyoseung; Wang, Xu; Yu, Cunjiang; Li, Yuhang; Linghu, Changhong; Song, Jizhou; Gao, Yang

    2017-01-01

    The considerable need to enhance data and hardware security suggest one possible future for electronics where it is possible to destroy them and even make them disappear physically. This paper reports a type of destructive electronics which features fast transience from chemical dissolution on-demand triggered in an electrochemical-mechanical manner. The detailed materials, mechanics, and device construction of the destructive electronics are presented. Experiment and analysis of the triggered releasing and transience study of electronic materials, resistors and metal-oxide-semiconductor field effect transistors illustrate the key aspects of the destructive electronics. The reported destructive electronics is useful in a wide range of areas from security and defense, to medical applications (paper)

  3. Big Data Challenges in High Energy Physics Experiments: The ATLAS (CERN) Fast TracKer Approach

    CERN Document Server

    Sotiropoulou, Calliope Louisa; The ATLAS collaboration

    2016-01-01

    We live in the era of “Big Data” problems. Massive amounts of data are produced and captured, data that require significant amounts of filtering to be processed in a realistically useful form. An excellent example of a “Big Data” problem is the data processing flow in High Energy Physics experiments, in our case the ATLAS detector in CERN. In the Large Hadron Collider (LHC) 40 million collisions of bunches of protons take place every second, which is about 15 trillion collisions per year. For the ATLAS detector alone 1 Mbyte of data is produced for every collision or 2000 Tbytes of data per year. Therefore what is needed is a very efficient real-time trigger system to filter the collisions (events) and identify the ones that contain “interesting” physics for processing. One of the upgrades of the ATLAS Trigger system is the Fast TracKer system. The Fast TracKer is a real-time pattern matching machine able to reconstruct the tracks of the particles in the inner silicon detector of the ATLAS experim...

  4. Trigger system study of the dimuon spectrometer in the ALICE experiment at CERN-LHC

    International Nuclear Information System (INIS)

    Roig, O.

    1999-12-01

    This work is a contribution to the study of nucleus-nucleus collisions at the LHC with ALICE. The aim of this experiment is to search for a new phase of matter, the quark-gluon plasma (QGP). The dimuon forward spectrometer should measure one of the most promising probes of the QGP, the production of heavy quark vector mesons (J/ψ, γ, γ', γ'') through their muonic decays. The dimuon trigger selects the interesting events performing a cut on the transverse momentum of the tracks. The trigger decision is taken by a dedicated electronics using RPC (''Resistive Plate Chambers'') detector information. We have made our own R and D program on the RPC detector with various beam tests. We show the performances obtained during these tests of a low resistivity RPC operating in streamer mode. The ALICE requirements concerning the rate capability, the cluster size and the time resolution are fulfilled. We have optimised the trigger with simulations which include a complete description of the read-out planes and the trigger logic (algorithm). In particular, a technique of clustering is proposed and validated. A method called ''Ds reduction'' is introduced in order to limit the effects of combinatorial background on the trigger rates. The efficiencies and the trigger rates are calculated for Pb-Pb, Ca-Ca, p-p collisions at the LHC. Other more sophisticated cuts, on the invariant mass for example, using again the RPC information have been simulated but have not shown significant improvements of the trigger rates. (author)

  5. Optimization studies on the calorimetric second level tau trigger of the ATLAS experiment at the Large Hadron Collider

    CERN Document Server

    Perez Codina, Estel

    2008-01-01

    Moving to the high energy regime of LHC, the identification of tau leptons will become an important and very powerful tool, allowing the discovery of physics beyond the Standard Model. Many models, light SM Higgs and various SUSY models among them, predict an abundant production of taus with respect to other leptons. The ATLAS collaboration has developed tools to efficiently identify tau at trigger level, based on the advanced calorimetry and tracking capabilities. The work presented in this Master Thesis is focused on the optimization of the first trigger level energy thresholds and the second trigger level calorimetric variables. A systematic optimization is designed, which allows us to study the robustness of the trigger selection. The improvements achieved by using a sampling energy calibration are discussed. Finally, an optimization on the size of the calorimeter region used to calculate the trigger variables is performed.

  6. A Fastbus module for trigger applications based on a digital signal processor and on programmable gate arrays

    International Nuclear Information System (INIS)

    Battaiotto, P.; Colavita, A.; Fratnik, F.; Lanceri, L.; Udine Univ.

    1991-01-01

    The new generation of DSP microprocessors based on RISC and Harvard-like architectures can conveniently take the place of specially built processors in fast trigger circuits for high-energy physics experiments. Presently available programmable gate arrays are well matched to them in speed and contribute to simplify the design of trigger circuits. Using these components, we designed and constructed a Fastbus module. We describe an application for the total-energy trigger of DELPHI, performing the readout of digitized calorimeter trigger data and some simple computations in less than 3 μs. (orig.)

  7. RPCs as trigger detector for the ATLAS experiment performances, simulation and application to the level-1 di-muon trigger

    CERN Document Server

    Di Simone, A; Di Ciaccio, A

    2005-01-01

    In the muon spectrometer different detectors are used to provide trigger functionality and precision momentum measurements. In the pseudorapidity range |eta|<1 the first level muon trigger is based on Resistive Plate Chambers, gas ionization detectors which are characterized by a fast response and an excellent time resolution (<1.5ns). The working principles of the Resistive Plate Chambers will be illustrated in chapter 3. Given the long time of operation expected for the ATLAS experiment (~10 years), ageing phenomena have been carefully studied, in order to ensure stable long-term operation of all the subdetectors. Concerning Resistive Plate Chambers, a very extensive ageing test has been performed at CERN's Gamma Irradiation Facility on three production chambers. The results of this test are presented in chapter 4. One of the most commonly used gases in RPCs operation is C2H2F4, which during the gas discharge can produce fluorine ions. Being F one of the most aggressive elements in nature, the presenc...

  8. Development of a Concept for the Muon Trigger of the ATLAS Detector at the HL-LHC

    CERN Document Server

    Gadow, Paul Philipp

    Highly selective first level triggers are essential to exploit the full physics potential of the ATLAS experiment at the High Luminosity-Large Hadron Collider, where the instantaneous luminosity will exceed the LHC Run 1 instantaneous luminosity by almost an order of magnitude. The ATLAS experiment plans to increase the rate of the first trigger level to 1 MHz at 6 µs latency. The momentum resolution of the existing first level muon trigger is limited by the moderate position resolution of the trigger chambers. Including the data of the precision Monitored Drift Tube (MDT) chambers in the first level muon trigger decision will increase the selectivity of the first level muon trigger substantially. Run 1 LHC data with a centre-of-mass energy of $\\sqrt{s} = 8\\, \\textrm{TeV}$ and a bunch spacing of 25 ns was used to study the achievable selectivity of a muon trigger making use of the MDT data. It could be shown that it is not necessary to fully reconstruct the muon trajectory. The position and direction informa...

  9. Online / Offline reconstruction of trigger-less readout in the R3B experiment at FAIR

    International Nuclear Information System (INIS)

    Kresan, Dmytro; Al-Turany, Mohammad; Uhlig, Florian

    2015-01-01

    The R3B (Reactions with Rare Radioactive Beams) experiment is one of the planned experiments at the future FAIR facility at GSI Darmstadt. R3B will cover experimental reaction studies with exotic nuclei far off stability, thus enabling a broad physics program with rare-isotope beams with emphasis on nuclear structure and dynamics. Several different detection subsystems as well as sophisticated DAQ system and data-analysis software are being developed for this purpose. The data analysis software for R3B is based on FairRoot framework and called R3BRoot. R3BRoot is being used for simulation and detector design studies for the last few years. Recently, it was successfully used directly with the data acquisition and for the analysis of the R3B test beam-time in April 2014. For the future beam times the framework has to deal with the free streaming readout of the detectors. The implementation within R3BRoot to fulfil this trigger-less run mode will be discussed in this paper, as well as the set of tools developed for the online reconstruction and quality assurance of the data during the run. (paper)

  10. Experience of Percutaneous Trigger Finger Release under Local ...

    African Journals Online (AJOL)

    Background: Trigger finger is a common disorder of upper extremity. Majority of the patients can be treated conservatively but some resistant cases eventually need surgery. Aim: The aim of this study is to evaluate the results of percutaneous trigger finger release under local anesthesia. Subjects and Methods: This is a ...

  11. Particle physics experiments 1983

    International Nuclear Information System (INIS)

    Stuart, G.W.

    1983-01-01

    The report describes work carried out in 1983 on experiments approved by the Particle Physics Experiments Selection Panel. The contents consist of unedited contributions from each experiment. (author)

  12. The ATLAS FTK system: how to improve the physics potential with a tracking trigger

    CERN Document Server

    Iizawa, T; The ATLAS collaboration

    2014-01-01

    After a very successful data taking run, the ATLAS experiment is being upgraded to cope with the higher luminosity and higher center of mass energy that the Large Hadron Collider will provide in the next years. The Fast Tracker (FTK) trigger system, part of the ATLAS trigger upgrade program, is a highly parallel hardware device designed to operate at the level-1 trigger output rate. 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 Memories (AM). FTK provides global track reconstruction in the full inner silicon detector, with resolution comparable to the offline algorithms, in approximately 100 microseconds, allowing a fast and precise detection of the primary and secondary vertex information. The track and vertex information is then used by t...

  13. The ATLAS FTK system: how to improve the physics potential with a tracking trigger

    CERN Document Server

    Iizawa, T; The ATLAS collaboration

    2016-01-01

    After a very successful data taking run, the ATLAS experiment [1] is being upgraded to cope with the higher luminosity and higher center of mass energy that the Large Hadron Collider (LHC) will provide in the next years. The Fast Tracker (FTK) trigger system, part of the ATLAS trigger upgrade program, is a highly parallel hardware device 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). FTK provides global track reconstruction in the full inner silicon detector, with resolution comparable to the offline algorithms, in approximately 100 microseconds, allowing a fast and precise detection of the primary and secondary vertex information. The track and vertex information is then used by the high-level trigger (HLT) algorithms, allowing highly improved tr...

  14. 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...

  15. A fast filter processor as a part of the trigger logic in an elastic scattering experiment

    International Nuclear Information System (INIS)

    Kenyon Gjerpe, I.

    1981-01-01

    A fast special purpose processor as a part of the trigger logic in an elastic scattering experiment is described. The decision to incorporate such a processor was taken because the trigger rate was estimated to be an order of magnitude higher than the date taking capability of the on-line minicomputer, a NORD 10. The processor is capable of checking the coplanarity and the opening angle of the two outgoing tracks within about 100 μs. This is done with a spatial resolution of 1 mm by using two points each track given by 3 MWPCs. For comparison this is two orders of magnitude faster than the same algorithm coded in assembly language on a PDP 11/40. The main contribution to this increased speed is due to extensive use of pipelining and parallelism. When running with the processor in the trigger, 75% more elastic events per incoming beam particle were collected, and 3 times as many elastic events per trigger were recorded on to tape for further in-depth analysis, than previously. Due to major improvements in the primary trigger logic this was less than the gain initially anticipated. A first version of the processor was designed and constructed in the CERN DD division by J. Joosten, M. Letheren and B. Martin under the supervision of C. Verkerk. The author was involved in the final design, construction and testing, and subsequently was responsible for the intergration, programming and running of the processor in the experiment. (orig.)

  16. 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

  17. Particle physics experiments 1987

    International Nuclear Information System (INIS)

    Stuart, G.W.

    1988-01-01

    This report describes work carried out in 1987 on experiments approved by the Particle Physics Experiments Selection Panel (United Kingdom). The contents consist of unedited contributions from each experiment. (author)

  18. Aftershocks and triggering processes in rock fracture

    Science.gov (United States)

    Davidsen, J.; Kwiatek, G.; Goebel, T.; Stanchits, S. A.; Dresen, G.

    2017-12-01

    One of the hallmarks of our understanding of seismicity in nature is the importance of triggering processes, which makes the forecasting of seismic activity feasible. These triggering processes by which one earthquake induces (dynamic or static) stress changes leading to potentially multiple other earthquakes are at the core relaxation processes. A specic example of triggering are aftershocks following a large earthquake, which have been observed to follow certain empirical relationships such as the Omori-Utsu relation. Such an empirical relation should arise from the underlying microscopic dynamics of the involved physical processes but the exact connection remains to be established. Simple explanations have been proposed but their general applicability is unclear. Many explanations involve the picture of an earthquake as a purely frictional sliding event. Here, we present experimental evidence that these empirical relationships are not limited to frictional processes but also arise in fracture zone formation and are mostly related to compaction-type events. Our analysis is based on tri-axial compression experiments under constant displacement rate on sandstone and granite samples using spatially located acoustic emission events and their focal mechanisms. More importantly, we show that event-event triggering plays an important role in the presence of large-scale or macrocopic imperfections while such triggering is basically absent if no signicant imperfections are present. We also show that spatial localization and an increase in activity rates close to failure do not necessarily imply triggering behavior associated with aftershocks. Only if a macroscopic crack is formed and its propagation remains subcritical do we observe significant triggering.

  19. Pulsed power accelerator for material physics experiments

    Directory of Open Access Journals (Sweden)

    D. B. Reisman

    2015-09-01

    Full Text Available We have developed the design of Thor: a pulsed power accelerator that delivers a precisely shaped current pulse with a peak value as high as 7 MA to a strip-line load. The peak magnetic pressure achieved within a 1-cm-wide load is as high as 100 GPa. Thor is powered by as many as 288 decoupled and transit-time isolated bricks. Each brick consists of a single switch and two capacitors connected electrically in series. The bricks can be individually triggered to achieve a high degree of current pulse tailoring. Because the accelerator is impedance matched throughout, capacitor energy is delivered to the strip-line load with an efficiency as high as 50%. We used an iterative finite element method (FEM, circuit, and magnetohydrodynamic simulations to develop an optimized accelerator design. When powered by 96 bricks, Thor delivers as much as 4.1 MA to a load, and achieves peak magnetic pressures as high as 65 GPa. When powered by 288 bricks, Thor delivers as much as 6.9 MA to a load, and achieves magnetic pressures as high as 170 GPa. We have developed an algebraic calculational procedure that uses the single brick basis function to determine the brick-triggering sequence necessary to generate a highly tailored current pulse time history for shockless loading of samples. Thor will drive a wide variety of magnetically driven shockless ramp compression, shockless flyer plate, shock-ramp, equation of state, material strength, phase transition, and other advanced material physics experiments.

  20. 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 ...

  1. Particle physics experiments 1989

    International Nuclear Information System (INIS)

    Bairstow, R.

    1990-01-01

    This report describes work carried out in 1989 on experiments approved by the Particle Physics Experiments Selection Panel of Rutherford Appleton Laboratory. The contents consist of unedited contributions from each experiment. (author)

  2. The trigger for $K^0 \\rightarrow \\pi^{0}\\pi^{0}$ decays of the NA48 experiment at CERN

    OpenAIRE

    Barr, Giles David; Cundy, Donald C; Formenti, F; Gorini, B; Hallgren, Björn I; Iwanski, W; Kapusta, P; Laverrière, G C; Lenti, M; Mikulec, I; Velasco, M; Vossnack, O; Wahl, H; Ziolkowski, M; Porcu, M

    2001-01-01

    The trigger used for the collection of the samples of $K^{0}$ yields $\\pi^{0}\\pi^{0}$ decays in the NA48 experiment at CERN uses a novel pipeline design in order to satisfy the demanding specifications of a high rate kaon beam. The trigger algorithms, architecture and performance are described.

  3. Trigger and data acquisition

    CERN Multimedia

    CERN. Geneva; Gaspar, C

    2001-01-01

    Past LEP experiments generate data at 0.5 MByte/s from particle detectors with over a quarter of a million readout channels. The process of reading out the electronic channels, treating them, and storing the date produced by each collision for further analysis by the physicists is called "Data Acquisition". Not all beam crossings produce interesting physics "events", picking the interesting ones is the task of the "Trigger" system. In order to make sure that the data is collected in good conditions the experiment's operation has to be constantly verified. In all, at LEP experiments over 100 000 parameters were monitored, controlled, and synchronized by the "Monotoring and control" system. In the future, LHC experiments will produce as much data in a single day as a LEP detector did in a full year's running with a raw data rate of 10 - 100 MBytes/s and will have to cope with some 800 million proton-proton collisions a second of these collisions only one in 100 million million is interesting for new particle se...

  4. 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...

  5. Commissioning and validation of the ATLAS Level-1 topological trigger

    CERN Document Server

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

    2017-01-01

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

  6. Particle physics experiments 1982

    International Nuclear Information System (INIS)

    Rousseau, M.D.; Stuart, G.

    1983-01-01

    Work carried out in 1982 on 52 experiments approved by the Particle Physics Experiments Selection Panel is described. Each experiment is listed under title, collaboration, technique, accelerator, year of running, status and spokesman. Unedited contributions are given from each experiment. (U.K.)

  7. 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...

  8. Implementation of PHENIX trigger algorithms on massively parallel computers

    International Nuclear Information System (INIS)

    Petridis, A.N.; Wohn, F.K.

    1995-01-01

    The event selection requirements of contemporary high energy and nuclear physics experiments are met by the introduction of on-line trigger algorithms which identify potentially interesting events and reduce the data acquisition rate to levels that are manageable by the electronics. Such algorithms being parallel in nature can be simulated off-line using massively parallel computers. The PHENIX experiment intends to investigate the possible existence of a new phase of matter called the quark gluon plasma which has been theorized to have existed in very early stages of the evolution of the universe by studying collisions of heavy nuclei at ultra-relativistic energies. Such interactions can also reveal important information regarding the structure of the nucleus and mandate a thorough investigation of the simpler proton-nucleus collisions at the same energies. The complexity of PHENIX events and the need to analyze and also simulate them at rates similar to the data collection ones imposes enormous computation demands. This work is a first effort to implement PHENIX trigger algorithms on parallel computers and to study the feasibility of using such machines to run the complex programs necessary for the simulation of the PHENIX detector response. Fine and coarse grain approaches have been studied and evaluated. Depending on the application the performance of a massively parallel computer can be much better or much worse than that of a serial workstation. A comparison between single instruction and multiple instruction computers is also made and possible applications of the single instruction machines to high energy and nuclear physics experiments are outlined. copyright 1995 American Institute of Physics

  9. Installation, commissioning and performance of the trigger system of the Double Chooz experiment and the analysis of hydrogen capture neutrino events

    Energy Technology Data Exchange (ETDEWEB)

    Lucht, Sebastian

    2013-11-18

    The Double Chooz experiment is a reactor antineutrino experiment located at Chooz, a small town in the Ardennes region in the north of France close to the Belgium border. The aim of the experiment is to measure the leptonic mixing angle θ{sub 13}. The antineutrino flux is measured by two identical detectors at different distances from the reactor cores used as neutrino source, in a so called ''disappearance'' experiment. Double Chooz is a precision experiment because previous experiments indicated a small value of θ{sub 13}. Therefore, the systematic uncertainties introduced by background events and detector related components have to be as small as possible. The detector and all electronic components have been designed accordingly. The first part of this thesis describes the trigger and timing system of the Double Chooz experiment. This system triggers the data acquisition of the detector. It continuously monitors the signals of the photomultiplier tubes (PMTs) of the detector. These signals are summed for groups of PMTs (group signal) and for all PMTs (sum signal). The group signals are the input signals to the trigger system. They are discriminated by one threshold resulting in a multiplicity condition on the number of active group signal discriminators. The sum signal is discriminated by four thresholds. The default trigger configuration for the Double Chooz experiment is based on a combination on the sum signal discriminators and the multiplicity condition. In addition, the trigger system provides a common clock signal for all data acquisition components and an online event classification to allow an online data reduction. The trigger system was installed and commissioned in 2011. In this thesis the commissioning of the trigger system and its performance is presented. Furthermore the development and tests of possible improvements for the trigger system are presented and discussed. The second part of this thesis introduces a complementary

  10. Implementation and Performance of the ATLAS Jet Trigger

    CERN Document Server

    Klemetti, M; The ATLAS collaboration

    2009-01-01

    The ATLAS jet trigger is prepared to cover a variety of physics topics, ranging from QCD studies to searches for SUSY particles. In this paper we will present the challenges of the jet trigger, describing the implementation and the expected performance. In particular, we will review the current physics signatures, the expected rates, efficiencies and timing measurements as obtained from MC studies. Comparisons of the performance obtained with the two different granularities at LVL2 and different EF algorithms will be shown. An overview of teh implications of the trigger performance in the physics studies that include jet signatures will be shown.

  11. Topological and Central Trigger Processor for 2014 LHC luminosities

    CERN Document Server

    Simioni, E; The ATLAS collaboration; Bauss, B; Berge, D; Buscher, V; Childers, T; Degele, R; Dobson, E; Ebling, A; Ellis, N; Farthouat, P; Gabaldon, C; Gorini, B; Haas, S; Ji, W; Kaneda, M; Mattig, S; Messina, A; Meyer, C; Moritz, S; Pauly, T; Pottgen, R; Schafer, U; Spiwoks, R; Tapprogge, S; Wengler, T; Wenzel, V

    2012-01-01

    The ATLAS experiment is located at the European Center for Nuclear Research (CERN) in Switzerland. It is designed to observe phenomena that involve highly massive particles produced in the collisions at the Large Hadron Collider (LHC): the world’s largest and highest-energy particle accelerator. Event triggering and Data Acquisition is one of the extraordinary challenges faced by the detectors at the high luminosity LHC collider. During 2011, the LHC reached instantaneous luminosities of 4 10^33 cm−1 s−1 and produced events with up to 24 interactions per colliding proton bunch. This places stringent operational and physical requirements on the ATLAS Trigger in order to reduce the 40MHz collision rate to a manageable event storage rate of 400Hz and, at the same time, selecting those events considered interesting. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 75kHz and decision latency of less than 2.5 micro seconds. It is primarily composed of the Calori...

  12. Topological and Central Trigger Processor for 2014 LHC luminosities

    CERN Document Server

    Simioni, E; The ATLAS collaboration; Bauss, B; Berge, D; B\\"{u}scher, V; Childers, T; Degele, R; Dobson, E; Ebling, A; Ellis, N; Farthouat, P; Gabaldon, C; Gorini, B; Haas, S; Ji, W; Kaneda, M; M\\"{a}ttig, S; Messina, A; Meyer, C; Moritz, S; Pauly, T; Pottgen, R; Sch\\"{a}fer, U; Spiwoks, R; Tapprogge, S; Wengler, T; Wenzel, V

    2012-01-01

    The ATLAS experiment is located at the European Center for Nu- clear Research (CERN) in Switzerland. It is designed to observe phe- nomena that involve highly massive particles produced in the collisions at the Large Hadron Collider (LHC): the world’s largest and highest-energy particle accelerator. Event triggering and Data Acquisition is one of the extraordinary challenges faced by the detectors at the high luminosity LHC collider. During 2011, the LHC reached instantaneous luminosities of 4×10^33 cm−1 s−1 and produced events with up to 24 interactions per colliding proton bunch. This places stringent operational and physical requirements on the AT- LAS Trigger in order to reduce the 40MHz collision rate to a manageable event storage rate of 400Hz and, at the same time, selecting those events considered interesting. The Level-1 Trigger is the first rate-reducing step in the ATLAS Trigger, with an output rate of 75kHz and decision latency of less than 2.5μs. It is primarily composed of the Calorimete...

  13. A Fast hardware Tracker for the ATLAS Trigger system

    CERN Document Server

    Pandini, Carlo Enrico; The ATLAS collaboration

    2015-01-01

    The trigger system at the ATLAS experiment is designed to lower the event rate occurring from the nominal bunch crossing at 40 MHz to about 1 kHz for a designed LHC luminosity of 10$^{34}$ cm$^{-2}$ s$^{-1}$. After a very successful data taking run the LHC is expected to run starting in 2015 with much higher instantaneous luminosities and this will increase the load on the High Level Trigger system. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals, which requires a more extensive use of tracking information. The Fast Tracker (FTK) trigger system, part of the ATLAS trigger upgrade program, is a highly parallel hardware device designed to perform full-scan track-finding at the event rate of 100 kHz. FTK is a dedicated processor based on a mixture of advanced technologies. Modern, powerful, Field Programmable Gate Arrays form an important part of the system architecture, and the combinatorial problem of pattern r...

  14. Experiment Design and Analysis Guide - Neutronics & Physics

    Energy Technology Data Exchange (ETDEWEB)

    Misti A Lillo

    2014-06-01

    The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.

  15. 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.

  16. Performance and upgrade of the CMS electromagnetic calorimeter trigger for Run II

    CERN Document Server

    Sauvan, Jean-Baptiste

    2015-01-01

    The CMS experiment implements a sophisticated two-level online trigger selection system that achieves a rejection factor of nearly $10^5$. The level one (L1) trigger is based on coarse information coming from the calorimeters and the muon detectors while the high-level trigger combines fine-grain information from all sub-detectors. In the near future the LHC will increase its centre of mass energy to 13 TeV and progressively reach an instantaneous luminosity of $2\\times 10^{34}\\,\\textrm{cm}^{-2}\\textrm{s}^{-1}$. In order to guarantee a successful and ambitious physics program under this challenging environment, the CMS Trigger and Data acquisition system must be consolidated. In particular the L1 calorimeter Trigger hardware and architecture will be changed. The aim is to maintain the current thresholds and improve the performance. This programme will be achieved by using $\\mu$TCA (Advanced Mezzanine Card) architecture with fast optical links and latest generation FPGAs. Sophisticated object reconstruction al...

  17. Central Nervous System (CNS Disease Triggering Takotsubo Syndrome

    Directory of Open Access Journals (Sweden)

    Josef Finsterer

    2016-01-01

    Full Text Available Takotsubo syndrome (TTS is usually triggered by psychological or physical stress. One of the many physical sources of stress are central nervous system (CNS disorders. CNS disorders most frequently triggering TTS include subarachnoid bleeding, epilepsy, ischemic stroke, migraine, and intracerebral bleeding. More rare CNS-triggers of TTS include posterior reversible encephalopathy syndrome (PRES, amyotrophic lateral sclerosis, encephalitis, or traumatic brain or spinal cord injury. TTS triggered by any of the CNS disorders needs to be recognized since adequate treatment of TTS may improve the general outcome from the CNS disorder as well. Neurologists need to be aware of TTS as a complication of specific CNS disorders but TTS may be triggered also by CNS disorders so far not recognised as causes of TTS.

  18. A level-1 pixel based track trigger for the CMS HL-LHC upgrade

    CERN Document Server

    Moon, Chang-Seong

    2016-01-01

    We present feasibility studies to investigate the performance and interest of a Level-1 trigger based on pixels. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is based on real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of rare physics events from the large pile-up of events. The goal of adding the pixel information already at the real-time level of the selection is to help reducing the total Level-1 trigger rate while keeping a high selection capability. This is quite an innovative and challenging objective for the upgrade of the experiments for the High Luminosity LHC.

  19. 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)

  20. Simulated experiments in modern physics

    International Nuclear Information System (INIS)

    Tirnini, Mahmud Hasan

    1981-01-01

    Author.In this thesis a number of the basic experiments of atomic and nuclear physics are simulated on a microcomputer interfaced to a chart recorder and CRT. These will induce the student to imagine that he is actually performing the experiments. He will collect data to be worked out. The thesis covers the relevant material to set up such experiments in the modern physics laboratory

  1. Particle physics experiments 1986

    International Nuclear Information System (INIS)

    Stuart, G.W.

    1987-01-01

    The paper presents research work carried out in 1986 on 52 elementary particle experiments approved by the Particle Physics Experiments Selection Panel. Most of the experiments were collaborative and involved research groups from different countries. About half of the experiments were conducted at CERN, the remaining experiments employed the accelerators: LAMPT, LEP, PETRA, SLAC, and HERA. The contents consist of unedited contributions from each experiment. (U.K.)

  2. Data analysis at Level-1 Trigger level

    CERN Document Server

    Wittmann, Johannes; Aradi, Gregor; Bergauer, Herbert; Jeitler, Manfred; Wulz, Claudia; Apanasevich, Leonard; Winer, Brian; Puigh, Darren Michael

    2017-01-01

    With ever increasing luminosity at the LHC, optimum online data selection is getting 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. This paper illustrates how the Level-1 Trigger of the CMS experiment and in particular its concluding stage, the Global Trigger, take up this challenge.

  3. Particle physics experiments 1984

    International Nuclear Information System (INIS)

    Stuart, G.

    1985-01-01

    The Rutherford Appleton laboratory report describes work carried out in 1984 on experiments approved by the Particle Physics selection panel. The contents consist of unedited contributions from each experiment. (author)

  4. Installation and Commissioning of the CMS Level-1 Calorimeter Trigger Upgrade

    CERN Document Server

    AUTHOR|(CDS)2071552; Aggleton, Robin Cameron; Baber, Mark David John; Barbieri, Richard Alexander; Belknap, Donald Austin; Berryhill, Jeffrey; Brooke, James John; Bundock, Aaron; Cali, Ivan Amos; Cepeda, Maria Luisa; Dasgupta, Sudeshna; da Silva, J.C; Dasu, Sridhara Rao; Durkin, Timothy John; Fobes, Robert William; Ghabrous Larrea, Carlos; Gorski, Thomas; Grimes, Mark; Guilbaud, Maxime; Guo, Z; Hall, Geoffrey; Harder, Kristian; Harper, Sam; Iles, Gregory Michiel; Innocenti, Gian Michele; Ives, Sarah Joanne; Jones, John; Kreis, Benjamin Jonah; Lee, Y; Li, W; Lucas, Christopher; Lucas, Robyn Elizabeth; Marrouche, Jad; Newbold, David; Northup, Michael; Oljavo, I; Paramesvaran, Sudarshan; Rivera, Ryan Allen; Roland, Christof; Rose, A; Sankey, D; Smith, Wesley; Svetek, Ales; Tapper, Alexander; Thea, Alessandro; Tikalsky, Jesra Lilah; Uplegger, Lorenzo; Vicente, Marcelo; Williams, Thomas Stephen; Wyslouch, Boleslaw

    2016-01-01

    The Compact Muon Solenoid (CMS) experiment is currently installing upgrades to their Calorimeter Trigger for LHC Run 2 to ensure that the trigger thresholds can stay low, and physics data collection will not be compromised. The electronics will be upgraded in two stages. Stage-1 for 2015 will upgrade some electronics and links from copper to optical in the existing calorimeter trigger so that the algorithms can be improved and we do not lose valuable data before stage-2 can be fully installed by 2016. Stage-2 will fully replace the calorimeter trigger at CMS with a micro-TCA and optical link system. It requires that the updates to the calorimeter back-ends, the source of the trigger primitives, be completed. The new systemâ??s boards will utilize Xilinx Virtex-7 FPGAs and have hundreds of high-speed links operating at up to 10 Gbps to maximize data throughput. The integration, commissioning, and installation of stage-1 in 2015 will be described, as well as the integration and parallel installation of th...

  5. Results from an on-line non-leptonic neural trigger implemented in an experiment looking for beauty

    International Nuclear Information System (INIS)

    Baldanza, C.; Musico, P.; Novelli, P.; Passaseo, M.

    1995-01-01

    Results from a non-leptonic neural-network trigger hosted by experiment WA92, looking for beauty particle production from 350 GeV negative pions on a fixed Cu target, are presented. The neural trigger has been used to send events selected by means of a non-leptonic signature based on microvertex detector information to a special data stream, meant for early analysis. The non-leptonic signature, defined in a neural-network fashion, was devised so as to enrich the selected sample in the number of events containing C3 secondary vertices (i.e, vertices having three tracks with sum of electric charges equal to +1 or -1), which are sought for further analysis to identify charm and beauty non-leptonic decays. The neural trigger module consists of a VME crate hosting two MA16 digital neural chips from Siemens and two ETANN analog neural chips from Intel. During the experimental run, only the ETANN chips were operational. The neural trigger operated for two continuous weeks during the WA92 1993 run. For an acceptance of 15% for C3 events, the neural trigger yields a C3 enrichment factor of 6.6-7.1 (depending on the event sample considered), which multiplied by that already provided by the standard trigger leads to a global C3 enrichment factor of similar 150. In the event sample selected by the neural trigger, one every similar 7 events contains a C3 vertex. The response time of the neural trigger module is 5.8 μs. (orig.)

  6. Results from an on-line non-leptonic neural trigger implemented in an experiment looking for beauty

    Energy Technology Data Exchange (ETDEWEB)

    Baldanza, C. [INFN, Bologna (Italy). ANNETTHE; Bisi, F. [INFN, Bologna (Italy). ANNETTHE; Cotta-Ramusino, A. [INFN, Bologna (Italy). ANNETTHE; D`Antone, I. [INFN, Bologna (Italy). ANNETTHE; Malferrari, L. [INFN, Bologna (Italy). ANNETTHE; Mazzanti, P. [INFN, Bologna (Italy). ANNETTHE; Odorici, F. [INFN, Bologna (Italy). ANNETTHE; Odorico, R. [INFN, Bologna (Italy). ANNETTHE; Zuffa, M. [INFN, Bologna (Italy). ANNETTHE; Bruschini, C. [Istituto Nazionale di Fisica Nucleare, Genoa (Italy); Musico, P. [Istituto Nazionale di Fisica Nucleare, Genoa (Italy); Novelli, P. [Istituto Nazionale di Fisica Nucleare, Genoa (Italy); Passaseo, M. [European Organization for Nuclear Research, Geneva (Switzerland)

    1995-07-15

    Results from a non-leptonic neural-network trigger hosted by experiment WA92, looking for beauty particle production from 350 GeV negative pions on a fixed Cu target, are presented. The neural trigger has been used to send events selected by means of a non-leptonic signature based on microvertex detector information to a special data stream, meant for early analysis. The non-leptonic signature, defined in a neural-network fashion, was devised so as to enrich the selected sample in the number of events containing C3 secondary vertices (i.e, vertices having three tracks with sum of electric charges equal to +1 or -1), which are sought for further analysis to identify charm and beauty non-leptonic decays. The neural trigger module consists of a VME crate hosting two MA16 digital neural chips from Siemens and two ETANN analog neural chips from Intel. During the experimental run, only the ETANN chips were operational. The neural trigger operated for two continuous weeks during the WA92 1993 run. For an acceptance of 15% for C3 events, the neural trigger yields a C3 enrichment factor of 6.6-7.1 (depending on the event sample considered), which multiplied by that already provided by the standard trigger leads to a global C3 enrichment factor of similar 150. In the event sample selected by the neural trigger, one every similar 7 events contains a C3 vertex. The response time of the neural trigger module is 5.8 {mu}s. (orig.).

  7. 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

  8. 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)

  9. Study and realisation of a digital TDC in the framework of the GANIL trigger

    International Nuclear Information System (INIS)

    Boujrad, Abderrahman

    2001-01-01

    In nuclear physics, the interaction between the ion beam and the target produces a large amount of events. Some of these events have no interest for the studied physical phenomenon; the useful events are sorted using a trigger. We have studied and realized a new trigger suitable for the GANIL (Grand Accelerateur National d'Ions Lourds) experiments. After an overview of the triggers used up to now at GANIL, we give the main features of the new trigger (GANIL Master Trigger, GMT) such as modularity, universality and versatility. After a description of the trigger operating modes, we depict the trigger realization steps. The trigger informs about fired detectors in a beam to target collision but gives no information about timing, nevertheless the timing is a very important piece of information if the trigger analysis duration is several times greater than the beam period. We suggest a timing measurement structure (Time to Digital Converter, TDC) able to eliminate this imprecision. The dead time, the low level integration and the consumption constraints lead us to prefer a digital architecture based on a digital counter associated with delay lines. Simple equations are given in order to define the operating area of the TDC. This area depends on the clock duty cycle and on the delay line taps. Measures of Differential Non Linearity (DNL) for different time resolutions (1, 2, 5 and 10 ns) allow us to establish the limits of this System and to underline some solutions to improve these features. (author) [fr

  10. 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...

  11. Physical Education as a territory to possible gender establishment: school experiences of transvestites, transexuals and transgender people

    Directory of Open Access Journals (Sweden)

    Neil Franco

    2016-05-01

    Full Text Available The Physical Education class at school interpreted through the experiences of the people who go beyond and/or live on the borders of gender is the focus of this study. It highlights considerations triggered by the analysis of the folder “A travesti e [o/a] educador[/a]” – about the insertion of these subjects in the Physical Education class –, correlated to bibliographic sources, interviews and questionnaires given to transvestite, transexuals and transgender brazilian teachers. It was concluded that, not unlike the school as a whole, Physical Education is also a space that exalts the incoherence between the reality of the educational routine and the norms that determine the school as a manager of inclusion.

  12. The Lived Experience of Lupus Flares: Features, Triggers, and Management in an Australian Female Cohort

    Directory of Open Access Journals (Sweden)

    Marline L. Squance

    2014-01-01

    Full Text Available Individuals living with lupus commonly experience daily backgrounds of symptoms managed to acceptable tolerance levels to prevent organ damage. Despite management, exacerbation periods (flares still occur. Varied clinical presentations and unpredictable symptom exacerbation patterns provide management and assessment challenges. Patient perceptions of symptoms vary with perceived impact, lifestyles, available support, and self-management capacity. Therefore, to increase our understanding of lupus’ health impacts and management, it was important to explore lupus flare characteristics from the patient viewpoint. Lupus flares in 101 Australian female patients were retrospectively explored with the use of a novel flare definition. Qualitative methods were used to explore patient-perceived flare symptoms, triggers, and management strategies adopted to alleviate symptom exacerbations. A mean of 29.9 flare days, with 6.8 discrete flares, was experienced. The study confirmed that patients perceive stress, infection, and UV light as flare triggers and identified new potential triggers of temperature and weather changes, work, and chemical exposure from home cleaning. The majority of flares were self-managed with patients making considered management choices without medical input. Barriers to seeking medical support included appointment timings and past negative experiences reflecting incongruence between clinician and patient views of symptom impact, assessment, and ultimately flare occurrence.

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

    CERN Document Server

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

    2017-01-01

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

  14. 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.)

  15. On-line trigger processor in PETRA/DORIS experiments at DESY

    CERN Document Server

    ölschläger, R

    1981-01-01

    Data, presented at a poster session, on on-line trigger processing are given. Brief details of trigger processors at the detectors CELLO, TASSO and ARAUS are shown, including: general working method; IC technology; power consumption; logic elements for trigger decision; number of chambers; number of input wires; execution time; parameter variation; links to host computer; cost; test features. (0 refs).

  16. The ATLAS b-jet Trigger

    CERN Document Server

    Ferreira de Lima, D E; The ATLAS collaboration

    2011-01-01

    The ATLAS detector, at the LHC, has a three-level trigger, which selects events relevant for the physics goals of the experiment. The identification of jets arising from bottom quark production is important in many analyses. The b-tagging at the ATLAS Trigger relies on the fragmentation of the b quark, which generates a B hadron, that retains most of the parent quark’s momentum (∼ 70%). Furthermore, the high b quark mass results in decay products with high momenta with respect to the jet axis. The lifetime tagger relies on the the relatively long lifetime of the B hadrons (∼ 1.6 ps in their rest frame), which allows them to have a long decay length. Due to the large mass of the B hadron, the tracks reconstructed from this decay often have large impact parameters, compared to prompt jets. The algorithms exploit this by identifying tracks from the B hadron decay which are displaced from the primary interaction vertex and thus, indicate that a long-lived particle was present. The latest performance results...

  17. A simulation framework for the CMS Track Trigger electronics

    International Nuclear Information System (INIS)

    Amstutz, C.; Weber, M.; Magazzù, G.; Palla, F.

    2015-01-01

    A simulation framework has been developed to test and characterize algorithms, architectures and hardware implementations of the vastly complex CMS Track Trigger for the high luminosity upgrade of the CMS experiment at the Large Hadron Collider in Geneva. High-level SystemC models of all system components have been developed to simulate a portion of the track trigger. The simulation of the system components together with input data from physics simulations allows evaluating figures of merit, like delays or bandwidths, under realistic conditions. The use of SystemC for high-level modelling allows co-simulation with models developed in Hardware Description Languages, e.g. VHDL or Verilog. Therefore, the simulation framework can also be used as a test bench for digital modules developed for the final system

  18. A simulation framework for the CMS Track Trigger electronics

    Science.gov (United States)

    Amstutz, C.; Magazzù, G.; Weber, M.; Palla, F.

    2015-03-01

    A simulation framework has been developed to test and characterize algorithms, architectures and hardware implementations of the vastly complex CMS Track Trigger for the high luminosity upgrade of the CMS experiment at the Large Hadron Collider in Geneva. High-level SystemC models of all system components have been developed to simulate a portion of the track trigger. The simulation of the system components together with input data from physics simulations allows evaluating figures of merit, like delays or bandwidths, under realistic conditions. The use of SystemC for high-level modelling allows co-simulation with models developed in Hardware Description Languages, e.g. VHDL or Verilog. Therefore, the simulation framework can also be used as a test bench for digital modules developed for the final system.

  19. Current experiments in elementary particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Wohl, C.G.; Armstrong, F.E., Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Frosch, R.; Olin, A.; Lehar, F.; Moskalev, A.N.; Barkov, B.P.

    1987-03-01

    This report contains summaries of 720 recent and current experiments in elementary particle physics (experiments that finished taking data before 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  20. Current experiments in elementary particle physics

    International Nuclear Information System (INIS)

    Wohl, C.G.; Armstrong, F.E.; Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Frosch, R.; Olin, A.; Lehar, F.; Moskalev, A.N.; Barkov, B.P.

    1987-03-01

    This report contains summaries of 720 recent and current experiments in elementary particle physics (experiments that finished taking data before 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized

  1. 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.

  2. 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.

  3. 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.

  4. Development of a new scintillation-trigger detector for the MTV experiment using aluminum-metallized film tape

    Science.gov (United States)

    Sakamoto, Yuko; Ozaki, Sachi; Tanaka, Saki; Tanuma, Ryosuke; Yoshida, Tatsuru; Murata, Jiro

    2014-09-01

    A new type of trigger-scintillation counter array designed for the MTV experiment at TRIUMF-ISAC has been developed, using aluminum-metallized film tape for wrapping. The MTV experiment aims to perform the finest precision test of time reversal symmetry in nuclear beta decay. In that purpose, we search non-zero T-Violating transverse polarization of electrons emitted from polarized Li-8 nuclei. It uses a cylindrical drift chamber (CDC) as the main electron-tracking detector. The trigger-scintillation counter consists of 12-segmented 1 mm thick 300 mm long thin plastic scintillation counters. This counter is placed inside the CDC to generate a trigger signal. The required assembling precision of +-0.5 mm was a tricky point when we tried to use conventional total reflection mode. Indeed, produce an air-layer surrounding the scintillating bar to keep good light transmission was the main issue. For this reason, we tried to use a new wrapping material made of metallized-aluminum tape, which has a good mirror-like reflecting surface on both sides of the tape. Through this report, we will compare detection efficiency and light attenuation between conventional and new wrapping materials.

  5. A level-1 pixel based track trigger for the CMS HL-LHC upgrade

    CERN Document Server

    CMS Collaboration

    2016-01-01

    We present feasibility studies to investigate the performances and interest of a Level-1 trigger based on pixels. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is based on the real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of the rare physics events from the large pile-up (PU) of events. The goal of adding the pixel information already at the real-time level of the selection is to help reducing the total level-1 trigger rate while keeping an high selection capability. This is quite an innovative and challenging objective for the experiments upgrade for the High Luminosity LHC (HL-LHC).

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

    CERN Document Server

    Helary, Louis; The ATLAS collaboration

    2017-01-01

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

  7. The CMS calorimeter trigger upgrade for the LHC Run II

    CERN Document Server

    Zabi, Alexandre

    2014-01-01

    The CMS experiment implements a sophisticated two-level online selection system that achieves a rejection factor of nearly 10e5. The first level (L1) is based on coarse information coming from the calorimeters and the muon detectors while the High-Level Trigger combines fine-grain information from all sub-detectors. During Run II, the LHC will increase its centre of mass energy up to 13 TeV and progressively reach an instantaneous luminosity of 2e34 cm-2s-1. In order to guarantee a successful and ambitious physics program under this intense environment, the CMS Trigger and Data acquisition system must be consolidated. In particular the L1 calorimeter Trigger hardware and architecture will be modified. The goal is to maintain the current thresholds (e.g., for electrons and photons) and improve the performance for the selection of tau leptons. This can only be achieved by designing an updated trigger architecture based on the recent microTCA technology. Racks can be equipped with fast optical links and latest...

  8. A Measurement of the ATLAS Di-Muon Trigger Efficiency in Proton-Proton Collision at √s = 7 TeV

    Directory of Open Access Journals (Sweden)

    Picazio Attilio

    2012-06-01

    Full Text Available The B physics programme of the ATLAS experiment includes measurements of production cross sections, searches for rare B-decay signatures which are sensitive to new physics at the TeV energy scale and studies of CP violation effects in B-events, such as Bs0 → J/ψφ and Bd0 → J/ψKs0. The key to the detection of these B signals in ATLAS is to achieve a high trigger efficiency for low-pT di-muon events, whilst keeping an acceptable trigger rate. ATLAS developed two separate approaches for triggering on di-muon events from resonances such as J/ψ and Upsilon (γ. The first approach is to start from a di-muon trigger selected at Level-1 while the second is based on dedicated Level-2 algorithms. The performance for these triggers has been studied using collision data at √s = 7 collected in 2011.

  9. 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...

  10. 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)

  11. Intelligent trigger by massively parallel processors for high energy physics experiments

    International Nuclear Information System (INIS)

    Rohrbach, F.; Vesztergombi, G.

    1992-01-01

    The CERN-MPPC collaboration concentrates its effort on the development of machines based on massive parallelism with thousands of integrated processing elements, arranged in a string. Seven applications are under detailed studies within the collaboration: three for LHC, one for SSC, two for fixed target high energy physics at CERN and one for HDTV. Preliminary results are presented. They show that the objectives should be reached with the use of the ASP architecture. (author)

  12. Need Satisfaction Moderates the Association Between Physical Activity and Affective States in Adults Aged 50+: an Activity-Triggered Ambulatory Assessment.

    Science.gov (United States)

    Kanning, Martina; Hansen, Sylvia

    2017-02-01

    Substantial evidence shows that physical activities of daily living are positively correlated with affective states in middle-aged and older adults. However, people's physical activity decreases when they grow older, and conditions that enhance older individuals' physical activities of daily living are not well understood. This study investigated need satisfaction (competence, relatedness, and autonomy) and its moderating effect on the within-subject relation between physical activities of daily living and three dimensions of affective states (valence, energetic arousal, and calmness) based on an ambulatory assessment that used activity-triggered e-diaries. The physical activities of daily living of 68 adults aged 50+ (mean age = 60.1 ± 7.1) were measured objectively for three consecutive days, and need satisfaction and affective states were assessed as a function of the amount of physical activity during the preceding 10 min before the affect measurement (in activity-triggered e-diaries). Hierarchical multilevel analyses were performed. Need satisfaction was significantly and positively correlated with the three dimensions of affective states. Further, physical activities of daily living were significantly associated with energetic arousal and calmness, but not valence. However, when physical activities of daily living were more autonomously regulated, the association of physical activities of daily living and valence became significant and positive. The findings regarding the significant moderating effects of need satisfaction are crucial for interventions aiming to improve the health-enhancing effects of physical activity in adults aged 50+. Positive feelings owing to physical activities in daily living depend on the extent that psychological needs are satisfied.

  13. Evaluation of gigabit links for use in HEP trigger processing

    International Nuclear Information System (INIS)

    Anderson, C.R.

    1999-05-01

    The next generation of colliders will take experimental particle physics into energy regimes where the potential for fundamental new discoveries is overshadowed by the immense technological challenges that have to be met in building the necessary detectors. One major technological challenge is to build detectors with fine granularity that can withstand the very high levels of radiation around the interaction region. The final challenge is to build and operate the high speed electronics that can readout and process the huge volumes of data that will be generated. In particular, a key demand is that efficient triggers be built that will filter out as much of the background as possible at as early a stage as possible, without losing or biasing the tiny physics signal. These triggers must be fast and affordable. This thesis is concerned with one aspect of this scenario: how to provide a low cost but very fast switching system that can direct the streams of data coming from the detector into the computers that run the trigger algorithms. In this thesis the design and evaluation of a novel new switching chip, the RCUBE, developed in collaboration with European industry, is presented. It will be shown that such a chip could offer a solution to the data switching problems likely to be encountered in a typical future collider experiment such as the ATLAS experiment at CERN. To help with planning the use of such a chip, a simulation package is also developed based on the commercial OPNET package

  14. 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.

  15. 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...

  16. Design studies for the Double Chooz trigger

    International Nuclear Information System (INIS)

    Cucoanes, Andi Sebastian

    2009-01-01

    The main characteristic of the neutrino mixing effect is assumed to be the coupling between the flavor and the mass eigenstates. Three mixing angles (θ 12 , θ 23 , θ 13 ) are describing the magnitude of this effect. Still unknown, θ 13 is considered very small, based on the measurement done by the CHOOZ experiment. A leading experiment will be Double Chooz, placed in the Ardennes region, on the same site as used by CHOOZ. The Double Chooz goal is the exploration of ∝80% from the currently allowed θ 13 region, by searching the disappearance of reactor antineutrinos. Double Chooz will use two similar detectors, located at different distances from the reactor cores: a near one at ∝150 m where no oscillations are expected and a far one at 1.05 km distance, close to the first minimum of the survival probability function. The measurement foresees a precise comparison of neutrino rates and spectra between both detectors. The detection mechanism is based on the inverse β-decay. The Double Chooz detectors have been designed to minimize the rate of random background. In a simplified view, two optically separated regions are considered. The target, filled with Gd-doped liquid scintillator, is the main antineutrino interaction volume. Surrounding the target, the inner veto region aims to tag the cosmogenic muon background which hits the detector. Both regions are viewed by photomultipliers. The Double Chooz trigger system has to be highly efficient for antineutrino events as well as for several types of background. The trigger analyzes discriminated signals from the central region and the inner veto photomultipliers. The trigger logic is fully programmable and can combine the input signals. The trigger conditions are based on the total energy released in event and on the PMT groups multiplicity. For redundancy, two independent trigger boards will be used for the central region, each of them receiving signals from half of the photomultipliers. A third trigger board

  17. Network based on statistical multiplexing for event selection and event builder systems in high energy physics experiments

    International Nuclear Information System (INIS)

    Calvet, D.

    2000-03-01

    Systems for on-line event selection in future high energy physics experiments will use advanced distributed computing techniques and will need high speed networks. After a brief description of projects at the Large Hadron Collider, the architectures initially proposed for the Trigger and Data AcQuisition (TD/DAQ) systems of ATLAS and CMS experiments are presented and analyzed. A new architecture for the ATLAS T/DAQ is introduced. Candidate network technologies for this system are described. This thesis focuses on ATM. A variety of network structures and topologies suited to partial and full event building are investigated. The need for efficient networking is shown. Optimization techniques for high speed messaging and their implementation on ATM components are described. Small scale demonstrator systems consisting of up to 48 computers (∼1:20 of the final level 2 trigger) connected via ATM are described. Performance results are presented. Extrapolation of measurements and evaluation of needs lead to a proposal of implementation for the main network of the ATLAS T/DAQ system. (author)

  18. The Level-1 Global Muon Trigger for the CMS Experiment

    OpenAIRE

    Sakulin, H; Taurok, Anton

    2003-01-01

    The three independent Level-1 muon trigger systems in CMS deliver up to 16 muon candidates per bunch crossing, each described by transverse momentum, direction, charge and quality. The Global Muon Trigger combines these measurements in order to find the best four muon candidates in the entire detector and attaches bits from the calorimeter trigger to denote calorimetric isolation and confirmation. A single-board logic design is presented: via a special front panel and a custom back plane more...

  19. 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

  20. 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.

  1. A Highly Selective First-Level Muon Trigger With MDT Chamber Data for ATLAS at HL-LHC

    CERN Document Server

    INSPIRE-00390105

    2016-07-11

    Highly selective triggers are essential for the physics programme of the ATLAS experiment at HL-LHC where the instantaneous luminosity will be about an order of magnitude larger than the LHC instantaneous luminosity in Run 1. The first level muon trigger rate is dominated by low momentum muons below the nominal trigger threshold due to the moderate momentum resolution of the Resistive Plate and Thin Gap trigger chambers. The resulting high trigger rates at HL-LHC can be su?ciently reduced by using the data of the precision Muon Drift Tube chambers for the trigger decision. This requires the implementation of a fast MDT read-out chain and of a fast MDT track reconstruction algorithm with a latency of at most 6 microseconds. A hardware demonstrator of the fast read-out chain has been successfully tested at the HL-LHC operating conditions at the CERN Gamma Irradiation Facility. The fast track reconstruction algorithm has been implemented on a fast trigger processor.

  2. A Highly Selective First-Level Muon Trigger With MDT Chamber Data for ATLAS at HL-LHC

    CERN Document Server

    Nowak, Sebastian; The ATLAS collaboration

    2015-01-01

    Highly selective triggers are essential for the physics programme of the ATLAS experiment at HL-LHC where the instantaneous luminosity will be about an order of magnitude larger than the LHC design luminosity. The Level-1 muon trigger rate is dominated by low momentum muons below the nominal trigger threshold due to the limited momentum resolution of the Resistive Plate and Thin Gap trigger chambers. The resulting high trigger rates at HL-LHC can be sufficient reduced by using the data of the precision Muon Drift Tube chambers for the trigger decision. This requires the implementation of a fast MDT read-out chain and of a fast MDT track reconstruction algorithm with a latency of at most 6~$\\mu$s. A hardware demonstrator of the fast read-out chain has been successfully tested at the high HL-LHC background rates at the CERN Gamma Irradiation Facility. The fast track reconstruction algorithm has been implemented on a fas trigger processor.

  3. Too much of a good thing: How to trigger in a signal-rich environment

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Large beauty and charm cross-sections make the LHC an ideal place to study the physics of heavy flavour, but the rate of signals of interest to the LHCb experiment, particularly after LS2, mean that a conventional trigger design with further offline reconstruction would overwhelm the available computing resources. In this seminar I will describe the novel approaches LHCb is using in the trigger to reconstruct and select only the data required for analysis in Run 3, several of which have already been put into operation during Run 2. 

  4. Architecture of a Level 1 Track Trigger for the CMS Experiment

    CERN Document Server

    Heintz, Ulrich

    2010-01-01

    The luminosity goal for the Super-LHC is 1035/cm2/s. At this luminosity the number of proton-proton interactions in each beam crossing will be in the hundreds. This will stress many components of the CMS detector. One system that has to be upgraded is the trigger system. To keep the rate at which the level 1 trigger fires manageable, information from the tracker has to be integrated into the level 1 trigger. Current design proposals foresee tracking detectors that perform on-detector filtering to reject hits from low-momentum particles. In order to build a trigger system, the filtered hit data from different layers and sectors of the tracker will have to be transmitted off the detector and brought together in a logic processor that generates trigger tracks within the time window allowed by the level 1 trigger latency. I will describe a possible architecture for the off-detector logic that accomplishes this goal.

  5. Analysis of pre-service physics teacher skills designing simple physics experiments based technology

    Science.gov (United States)

    Susilawati; Huda, C.; Kurniawan, W.; Masturi; Khoiri, N.

    2018-03-01

    Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.

  6. The CDF Silicon Vertex Trigger

    International Nuclear Information System (INIS)

    Dell'Orso, Mauro

    2006-01-01

    Motivations, design, performance and ongoing upgrade of the CDF Silicon Vertex Trigger are presented. The system provides CDF with a powerful tool for online tracking with offline quality in order to enhance the reach on B-physics and large P t -physics coupled to b quarks

  7. A simulation framework for the CMS Track Trigger electronics

    CERN Document Server

    Amstutz, Christian; Weber, Marc; Palla, Fabrizio

    2014-01-01

    A simulation framework has been developed to test and characterize algorithms, architectures and hardware implementations of the vastly complex CMS Track Trigger for the high luminosity upgrade of the CMS experiment at the Large Hadron Collider in Geneva. High-level SystemC models of all system components have been developed to simulate a portion of the track trigger. The simulation of the system components together with input data from physics simulations allows evaluating figures of merit, like delays or bandwidths, under realistic conditions. The use of SystemC for high-level modelling allows \\mbox{co-simulation} with models developed in Hardware Description Languages, e.g.~VHDL or Verilog. Therefore, the simulation framework can also be used as a test bench for digital modules developed for the final system.

  8. 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.

  9. Real-time track-less Cherenkov ring fitting trigger system based on Graphics Processing Units

    Science.gov (United States)

    Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cretaro, P.; Cotta Ramusino, A.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Gianoli, A.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P. S.; Pastorelli, E.; Piandani, R.; Piccini, M.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

    2017-12-01

    The parallel computing power of commercial Graphics Processing Units (GPUs) is exploited to perform real-time ring fitting at the lowest trigger level using information coming from the Ring Imaging Cherenkov (RICH) detector of the NA62 experiment at CERN. To this purpose, direct GPU communication with a custom FPGA-based board has been used to reduce the data transmission latency. The GPU-based trigger system is currently integrated in the experimental setup of the RICH detector of the NA62 experiment, in order to reconstruct ring-shaped hit patterns. The ring-fitting algorithm running on GPU is fed with raw RICH data only, with no information coming from other detectors, and is able to provide more complex trigger primitives with respect to the simple photodetector hit multiplicity, resulting in a higher selection efficiency. The performance of the system for multi-ring Cherenkov online reconstruction obtained during the NA62 physics run is presented.

  10. Experience of Initial Symptoms of Breast Cancer and Triggers for Action in Ethiopia

    International Nuclear Information System (INIS)

    Dye, T.D.; Hobden, C.; Reeler, A.; Dye, T.D.; Bogale, S.; Tilahun, Y.; Deressa, T.

    2012-01-01

    Objective. This study assessed the initial experiences, symptoms, and actions of patients in Ethiopia ultimately determined to have breast cancer. Methods. 69 participants in a comprehensive breast cancer treatment program at the main national cancer hospital in Ethiopia were interviewed using mixed qualitative and quantitative approaches. Participants narratives of their initial cancer experience were coded and analyzed for themes around their symptoms, time to seeking advice, triggers for action, and contextual factors. The assessment was approved by the Addis Ababa University Faculty of Medicine Institutional Review Board. Results. Nearly all women first noticed lumps, though few sought medical advice within the first year (average time to action: 1.5 years). Eventually, changes in their symptoms motivated most participants to seek advice. Most participants did not think the initial lump would be cancer, nor was a lump of any particular concern until symptoms changed. Conclusion. Given the frequency with which lumps are the first symptom noticed, raising awareness among participants that lumps should trigger medical consultation could contribute significantly to more rapid medical advice-seeking among women in Ethiopia. Primary care sites should be trained and equipped to offer evaluation of lumps so that women can be referred appropriately for assessment if needed

  11. A Level 1 Tracking Trigger for the CMS Experiment

    CERN Document Server

    Pozzobon, Nicola

    2011-01-01

    The LHC machine is planned to be upgraded in the next decade in order to deliver a luminosity about 5 to 10 times larger than the design one of $10^{34}$ cm$^{-2}$s$^{-1}$. In this scenario, a novel tracking system for the CMS experiment is required to be conceived and built. The main requirements on the CMS tracker are presented. Particular emphasis will be given to the challenging capability of the tracker to provide useful information for the Level 1 hardware trigger, complementary to the muon system and calorimeter ones. Different approaches based on pattern hit correlation within closely placed sensors are currently under evaluation, making use of either strips or macro-pixels. A proposal to optimize the data flow at the front-end ASIC and develop a tracking algorithm to provide tracks at Level 1 will be presented.

  12. Development of Advanced Gaseous Detectors for Muon Tracking and Triggering in Collider Experiments

    CERN Document Server

    Guan, Liang; Zhao, Zhengguo; Zhu, Junjie

    High luminosity and high energy collider experiments impose big challenges to conventional gaseous detectors used for muon tracking and triggering. Stringent requirements, in terms of time and spatial resolutions, rate capabilities etc. are expected. In the context of ATLAS muon upgrade project, we present extensive researches and developments of advanced gas detectors for precision muon tracking and triggering in high rate environments. Particularly, this dissertation focuses on the studies of Micro-mesh Gaseous structure (Micromegas), thin gap Resistive Plate Chamber (RPC) and small strip Thin Gap multi-wire Chambers (sTGC). In this dissertation, we first present a novel method, based on thermally bonding micro-meshes to anodes, to construct Micromegas detectors. Without employing the traditional photo-lithography process, it is a convenient alternative to build Micromegas. Both experimental and simulation studies of basic performance parameters of thermo-bonded Micromegas will be reported. Development...

  13. Development of a monitoring tool to validate trigger level analysis in the ATLAS experiment

    CERN Document Server

    Hahn, Artur

    2014-01-01

    This report summarizes my thirteen week summer student project at CERN from June 30th until September 26th of 2014. My task was to contribute to a monitoring tool for the ATLAS experiment, comparing jets reconstructed by the trigger to fully offline reconstructed and saved events by creating a set of insightful histograms to be used during run 2 of the Large Hadron Collider, planned to start in early 2015. The motivation behind this project is to validate the use of data taken solely from the high level trigger for analysis purposes. Once the code generating the plots was completed, it was tested on data collected during run 1 up to the year 2012 and Monte Carlo simulated events with center-of-mass energies ps = 8TeV and ps = 14TeV.

  14. Dataset definition for CMS operations and physics analyses

    Science.gov (United States)

    Franzoni, Giovanni; Compact Muon Solenoid Collaboration

    2016-04-01

    Data recorded at the CMS experiment are funnelled into streams, integrated in the HLT menu, and further organised in a hierarchical structure of primary datasets and secondary datasets/dedicated skims. Datasets are defined according to the final-state particles reconstructed by the high level trigger, the data format and the use case (physics analysis, alignment and calibration, performance studies). During the first LHC run, new workflows have been added to this canonical scheme, to exploit at best the flexibility of the CMS trigger and data acquisition systems. The concepts of data parking and data scouting have been introduced to extend the physics reach of CMS, offering the opportunity of defining physics triggers with extremely loose selections (e.g. dijet resonance trigger collecting data at a 1 kHz). In this presentation, we review the evolution of the dataset definition during the LHC run I, and we discuss the plans for the run II.

  15. Dataset definition for CMS operations and physics analyses

    CERN Document Server

    AUTHOR|(CDS)2051291

    2016-01-01

    Data recorded at the CMS experiment are funnelled into streams, integrated in the HLT menu, and further organised in a hierarchical structure of primary datasets, secondary datasets, and dedicated skims. Datasets are defined according to the final-state particles reconstructed by the high level trigger, the data format and the use case (physics analysis, alignment and calibration, performance studies). During the first LHC run, new workflows have been added to this canonical scheme, to exploit at best the flexibility of the CMS trigger and data acquisition systems. The concept of data parking and data scouting have been introduced to extend the physics reach of CMS, offering the opportunity of defining physics triggers with extremely loose selections (e.g. dijet resonance trigger collecting data at a 1 kHz). In this presentation, we review the evolution of the dataset definition during the first run, and we discuss the plans for the second LHC run.

  16. Um Processador Rápido de Corte em Momento Transverso para o Trigger da Experiência CP-LEAR

    CERN Document Server

    Machado, Emanuel Tito Mendes

    Neste trabalho pretendemos mostrar alguns aspectos importantes no desenho de instrumentação para sistemas de selecção de eventos (trigger), que se revelaram importantes no desenho do sistema de trigger de CP–LEAR. Para isso, fazemos um zoom progressivo sobre a experiência. Começamos por mostrar o que são sistemas de trigger, quais as suas propriedades e diversidade, e que tipos de sistemas são usados e em que circunstâncias. É também feito um apanhado do state of the art dos diversos componentes e soluções utilizadas para a resolução dos problemas típicos destes sistemas. A seguir, apresentamos CP–LEAR, descrevendo a física em que se apoia o seu método. Aqui introduzimos o conceito de simetrias, e em que circunstâncias podemos falar de violação de simetria. Seguidamente, introduzimos o sistema de kaões neutros, apresentamos o fenómeno de violação CP, e descrevemos o método de CP–LEAR utilizado para o seu estudo. Depois de apresentar o detector utilizado na experiência, começa...

  17. Particle physics experiments 1988

    International Nuclear Information System (INIS)

    Bairstow, R.

    1989-01-01

    This report describes work carried out in 1988 on experiments approved by the Particle Physics Experiments Selection Panel. The contents consist of unedited contributions from each experiment. More than forty projects at different accelerators (SPS, ISIS, PETRA, LAMPF, LEP, HERA, BNL, ILL, LEAR) are listed. Different organisations collaborate on different projects. A brief progress report is given. References to published articles are given. (author)

  18. 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

  19. Design studies for the Double Chooz trigger

    Energy Technology Data Exchange (ETDEWEB)

    Cucoanes, Andi Sebastian

    2009-07-24

    The main characteristic of the neutrino mixing effect is assumed to be the coupling between the flavor and the mass eigenstates. Three mixing angles ({theta}{sub 12}, {theta}{sub 23}, {theta}{sub 13}) are describing the magnitude of this effect. Still unknown, {theta}{sub 13} is considered very small, based on the measurement done by the CHOOZ experiment. A leading experiment will be Double Chooz, placed in the Ardennes region, on the same site as used by CHOOZ. The Double Chooz goal is the exploration of {proportional_to}80% from the currently allowed {theta}{sub 13} region, by searching the disappearance of reactor antineutrinos. Double Chooz will use two similar detectors, located at different distances from the reactor cores: a near one at {proportional_to}150 m where no oscillations are expected and a far one at 1.05 km distance, close to the first minimum of the survival probability function. The measurement foresees a precise comparison of neutrino rates and spectra between both detectors. The detection mechanism is based on the inverse {beta}-decay. The Double Chooz detectors have been designed to minimize the rate of random background. In a simplified view, two optically separated regions are considered. The target, filled with Gd-doped liquid scintillator, is the main antineutrino interaction volume. Surrounding the target, the inner veto region aims to tag the cosmogenic muon background which hits the detector. Both regions are viewed by photomultipliers. The Double Chooz trigger system has to be highly efficient for antineutrino events as well as for several types of background. The trigger analyzes discriminated signals from the central region and the inner veto photomultipliers. The trigger logic is fully programmable and can combine the input signals. The trigger conditions are based on the total energy released in event and on the PMT groups multiplicity. For redundancy, two independent trigger boards will be used for the central region, each of

  20. 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

  1. 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 ...

  2. 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 ...

  3. A new Highly Selective First Level ATLAS Muon Trigger With MDT Chamber Data for HL-LHC

    CERN Document Server

    Nowak, Sebastian; The ATLAS collaboration

    2015-01-01

    Highly selective first level triggers are essential for the physics programme of the ATLAS experiment at the HL-LHC where the instantaneous luminosity will exceed the LHC's instantaneous luminosity by almost an order of magnitude. The ATLAS first level muon trigger rate is dominated by low momentum sub-trigger threshold muons due to the poor momentum resolution at trigger level caused by the moderate spatial resolution of the resistive plate and thin gap trigger chambers. This limitation can be overcome by including the data of the precision muon drift tube chambers in the first level trigger decision. This requires the implementation of a fast MDT read-out chain and a fast MDT track reconstruction. A hardware demonstrator of the fast read-out chain was successfully tested under HL-LHC operating conditions at CERN's Gamma Irradiation Facility. It could be shown that the data provided by the demonstrator can be processed with a fast track reconstruction algorithm on an ARM CPU within the 6 microseconds latency...

  4. 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 ...

  5. The ATLAS Muon to Central Trigger Processor Interface Upgrade for the Run 3 of the LHC

    CERN Document Server

    Armbruster, Aaron James; The ATLAS collaboration; Chelstowska, Magda Anna

    2017-01-01

    To cope with the higher luminosity and physics cross-sections for the third run of the Large Hadron Collider (LHC) and beyond, the Trigger and Data Acquisition (TDAQ) system of ATLAS experiment at CERN is being upgraded. Part of the TDAQ system, the Muon to Central Trigger Processor Interface (MUCTPI) receives muon candidates information from each of the 208 barrel and endcap muon trigger sectors, counts muon candidates for each transverse momentum threshold and sends the result to the Central Trigger Processor (CTP). The MUCTPI takes into account the possible overlap between trigger sectors in order to avoid double counting of muon candidates. A full redesign and replacement of the existing MUCTPI is required in order to provide full-granularity muon position information at the bunch crossing rate to the Topological Trigger processor (L1Topo) and to be able to interface with the new sector logic modules. State-of-the-art FPGA technology and high-density ribbon fiber-optic transmitters and receivers is being...

  6. The ATLAS Muon-to-Central Trigger Processor Interface Upgrade for the Run 3 of the LHC

    CERN Document Server

    Armbruster, Aaron James; The ATLAS collaboration

    2017-01-01

    To cope with the higher luminosity and physics cross-sections for the third run of the Large Hadron Collider (LHC) and beyond, the Trigger and Data Acquisition (TDAQ) system of ATLAS experiment at CERN is being upgraded. Part of the TDAQ system, the Muon to Central Trigger Processor Interface (MUCTPI) receives muon candidates information from each of the 208 barrel and endcap muon trigger sectors, counts muon candidates for each transverse momentum threshold and sends the result to the Central Trigger Processor (CTP). The MUCTPI takes into account the possible overlap between trigger sectors in order to avoid double counting of muon candidates. A full redesign and replacement of the existing MUCTPI is required in order to provide full-granularity muon position information at the bunch crossing rate to the Topological Trigger processor (L1Topo) and to be able to interface with the new sector logic modules. State-of-the-art FPGA technology and high-density ribbon fiber-optic transmitters and receivers is being...

  7. Study of the electronic trigger system for HL-LHC project and search for new physics in top anti-top invariant mass spectrum with CMS experiment at LHC

    International Nuclear Information System (INIS)

    Beaupere, N.

    2012-01-01

    This manuscript describes my thesis work within the CMS experiment of the LHC collider. It presents both subjects on which I worked: a detector subject and a data analysis subject. The first subject, detector, is situated within the framework of the HL-LHC project which plans an increase by a factor five of the instantaneous luminosity. Such an increase and the preservation of the high level trigger (HLT) system, generate new constraints on the CMS detector. This is particularly true for the electronic trigger (L1) system. The CMS collaboration intends to implant this within tracker detector. Two methods are proposed: the stub modules method and the associative memory method. However, associative memory method requires a clever pre-selection of electric signals to be usable. The cluster width method is jointly proposed by Fabrizio Palla's team (Pisa) and by Didier Contardo's team (IPNL) to pre-select electric signals. The optimization of this method, in particular geometrical parameters of modules and thresholds applied for the electric signals pre-selection, is the result of my own work. It is detailed throughout the part III of this manuscript. The second subject concerns the analysis of data collected by CMS during 2011. This analysis has for objective to look for new particles in the spectre of anti-top top invariant mass. Due to its big mass, close to the electroweak symmetry breaking energy, the top quark plays an important role in numerous extensions of the Standard Model. The observation of narrow resonances in the spectre could be the sign of new particles. The analysis is subdivided into three parts, the selection of top anti-top events, the reconstruction of top anti-top invariant mass and a statistical study to quantify the presence of new physics. The results of this work are limits on the cross-section production of new particles. They are presented in the part IV of this manuscript. (author)

  8. Current experiments in elementary particle physics

    International Nuclear Information System (INIS)

    Galic, H.; Dodder, D.C.; Klyukhin, V.I.; Ryabov, Yu.G.; Illarionova, N.S.; Lehar, F.; Oyanagi, Y.; Frosch, R.

    1992-06-01

    This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries

  9. A high-resolution TDC-based board for a fully digital trigger and data acquisition system in the NA62 experiment at CERN

    CERN Document Server

    Pedreschi, Elena; Angelucci, Bruno; Avanzini, Carlo; Galeotti, Stefano; Lamanna, Gianluca; Magazzù, Guido; Pinzino, Jacopo; Piandani, Roberto; Sozzi, Marco; Spinella, Franco; Venditti, Stefano

    2015-01-01

    A Time to Digital Converter (TDC) based system, to be used for most sub-detectors in the high-flux rare-decay experiment NA62 at CERN SPS, was built as part of the NA62 fully digital Trigger and Data AcQuisition system (TDAQ), in which the TDC Board (TDCB) and a general-purpose motherboard (TEL62) will play a fundamental role. While TDCBs, housing four High Performance Time to Digital Converters (HPTDC), measure hit times from sub-detectors, the motherboard processes and stores them in a buffer, produces trigger primitives from different detectors and extracts only data related to the lowest trigger level decision, once this is taken on the basis of the trigger primitives themselves. The features of the TDCB board developed by the Pisa NA62 group are extensively discussed and performance data is presented in order to show its compliance with the experiment requirements.

  10. The Level 0 Pixel Trigger system for the ALICE experiment

    International Nuclear Information System (INIS)

    Rinella, G Aglieri; Kluge, A; Krivda, M

    2007-01-01

    The ALICE Silicon Pixel Detector contains 1200 readout chips. Fast-OR signals indicate the presence of at least one hit in the 8192 pixel matrix of each chip. The 1200 bits are transmitted every 100 ns on 120 data readout optical links using the G-Link protocol. The Pixel Trigger System extracts and processes them to deliver an input signal to the Level 0 trigger processor targeting a latency of 800 ns. The system is compact, modular and based on FPGA devices. The architecture allows the user to define and implement various trigger algorithms. The system uses advanced 12-channel parallel optical fiber modules operating at 1310 nm as optical receivers and 12 deserializer chips closely packed in small area receiver boards. Alternative solutions with multi-channel G-Link deserializers implemented directly in programmable hardware devices were investigated. The design of the system and the progress of the ALICE Pixel Trigger project are described in this paper

  11. An FPGA-based trigger processor for a measurement of deeply virtual Compton scattering at the COMPASS-II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schopferer, Sebastian

    2013-12-16

    The COMPASS-II experiment at CERN is focusing on a measurement of the deeply virtual Compton scattering. Several upgrades of the experimental setup have been performed in 2012, namely the construction of a long liquid hydrogen target and a surrounding recoil proton detector called CAMERA. Based on a time-of-flight measurement between two barrels of scintillators, the CAMERA detector allows to detect protons with a kinetic energy down to 35 MeV, which leave the target under large polar angles. At the same time, protons can be distinguished from other particles resulting from background processes by means of an energy loss measurement in the scintillating material. In order to extend the existing COMPASS trigger scheme, a digital trigger system has been developed, which is detailed in the thesis at hand. The trigger system is able to select events with a recoil proton in the final state while suppressing background events, using the particle identification capabilities of the CAMERA detector. Challenging selection criteria based on both the time-of-flight and the energy loss measurement call for a powerful programmable logic board. At the same time, the integration into the existing COMPASS trigger system poses strict constraints on the latency of the trigger decision. For the implementation of the proton trigger system, a new FPGA-based trigger and DAQ hardware called TIGER has been built. The module is operated in two firmware configurations, serving two distinct purposes. Firstly, the trigger processor is responsible for the generation of a trigger signal based on recoil particles, which is included in the global first-level trigger decision. Secondly, a readout concentrator allows to multiplex the data streams of up to 18 readout modules into one link to the DAQ. The CAMERA detector and the corresponding readout and trigger electronics was commissioned during a test run in autumn 2012. This thesis contains details about the trigger concept, the development of the

  12. 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.)

  13. Body-related pride in young adults: an exploration of the triggers, contexts, outcomes and attributions.

    Science.gov (United States)

    Castonguay, Andree L; Gilchrist, Jenna D; Mack, Diane E; Sabiston, Catherine M

    2013-06-01

    This study explored body-related emotional experiences of pride in young adult males (n=138) and females (n=165). Data were collected using a relived emotion task and analyzed using inductive content analysis. Thirty-nine codes were identified and grouped into six categories (triggers, contexts, cognitive attributions, and affective, cognitive, and behavioral outcomes) for each of two themes (hubristic and authentic pride). Hubristic pride triggers included evaluating appearance/fitness as superior. Cognitions centered on feelings of superiority. Behaviors included strategies to show off. Triggers for authentic pride were personal improvements/maintenance in appearance and meeting or exceeding goals. Feeling accomplished was a cognitive outcome, and physical activity was a behavioral strategy. Contexts for the experience of both facets of pride primarily involved sports settings, swimming/beach, and clothes shopping. These findings provide theoretical support for models of pride as it applies to body image, and advances conceptual understanding of positive body image. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Triggering Artefacts

    DEFF Research Database (Denmark)

    Mogensen, Preben Holst; Robinson, Mike

    1995-01-01

    and adapting them to specific situations need not be ad hoc.Triggering artefacts are a way of systematically challenging both designers' preunderstandings and the conservatism of work practice. Experiences from the Great Belt tunnel and bridge project are used to illustrate howtriggering artefacts change...

  15. 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...

  16. Experiments in Fundamental Neutron Physics

    OpenAIRE

    Nico, J. S.; Snow, W. M.

    2006-01-01

    Experiments using slow neutrons address a growing range of scientific issues spanning nuclear physics, particle physics, astrophysics, and cosmology. The field of fundamental physics using neutrons has experienced a significant increase in activity over the last two decades. This review summarizes some of the recent developments in the field and outlines some of the prospects for future research.

  17. 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.

  18. Aesthetic Experience as an Essential Factor to Trigger Positive Environmental Consciousness

    Directory of Open Access Journals (Sweden)

    Po-Ching Wang

    2018-04-01

    Full Text Available The current environmental attitude models are primarily composed of environmental knowledge, value, and intention. However, environmental aestheticians have maintained that aesthetic experience triggered by nature is the cornerstone of promoting environmental ethics. To verify this belief, this study proposes a new framework, which integrates the rational and emotional approaches, to describe the environmental attitudes of the public. Questionnaires are used to collect data from college students in Taiwan, and a total of 275 valid responses are received. The collected data are analyzed using structural equation modeling. The results support the proposed hypotheses. In addition to reconfirming the importance of environmental knowledge in the traditional models, this study confirms that aesthetic experience is also a determining dimension. The findings show that rational cognition and aesthetic perception complement and interact with each other and can strengthen environmental ethics, thereby enhancing the intention of pro-environmental behavior. The results of this study can serve as a reference for environmental protection or environmental education practice.

  19. 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...

  20. 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...

  1. 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 ...

  2. Current experiments in elementary particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D.C. (Los Alamos National Lab., NM (USA)); Ryabov, Yu.G.; Slabospitsky, S.R. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Serpukhov (USSR). Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla

    1989-09-01

    This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  3. Current experiments in elementary particle physics

    International Nuclear Information System (INIS)

    Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P.; Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Slabospitsky, S.R.; Olin, A.; Klumov, I.A.

    1989-09-01

    This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized

  4. Particle physics experiments 1992

    International Nuclear Information System (INIS)

    Roberts, B.A.

    1993-03-01

    The research programs described here were carried out in 1992 at Rutherford Appleton Laboratory and funded by the United Kingdom Science and Engineering Research Council. The area covered in these experiments is particle physics. Unedited contributions from over forty experimental programs are included. Experiments are listed according to their current status, the accelerator used and its years of operation. (UK)

  5. Physically Triggered Morphology Changes in a Novel Acremonium Isolate Cultivated in Precisely Engineered Microfabricated Environments

    Directory of Open Access Journals (Sweden)

    Laura Catón

    2017-07-01

    Full Text Available Fungi are strongly affected by their physical environment. Microfabrication offers the possibility of creating new culture environments and ecosystems with defined characteristics. Here, we report the isolation of a novel member of the fungal genus Acremonium using a microengineered cultivation chip. This isolate was unusual in that it organizes into macroscopic structures when initially cultivated within microwells with a porous aluminum oxide (PAO base. These “templated mycelial bundles” (TMB were formed from masses of parallel hyphae with side branching suppressed. TMB were highly hydrated, facilitating the passive movement of solutes along the bundle. By using a range of culture chips, it was deduced that the critical factors in triggering the TMB were growth in microwells from 50 to 300 μm in diameter with a PAO base. Cultivation experiments, using spores and pigments as tracking agents, indicate that bulk growth of the TMB occurs at the base. TMB morphology is highly coherent and is maintained after growing out of the microwells. TMB can explore their environment by developing unbundled lateral hyphae; TMB only followed if nutrients were available. Because of the ease of fabricating numerous microstructures, we suggest this is a productive approach for exploring morphology and growth in multicellular microorganisms and microbial communities.

  6. The double Chooz hardware trigger system

    Energy Technology Data Exchange (ETDEWEB)

    Cucoanes, Andi; Beissel, Franz; Reinhold, Bernd; Roth, Stefan; Stahl, Achim; Wiebusch, Christopher [RWTH Aachen (Germany)

    2008-07-01

    The double Chooz neutrino experiment aims to improve the present knowledge on {theta}{sub 13} mixing angle using two similar detectors placed at {proportional_to}280 m and respectively 1 km from the Chooz power plant reactor cores. The detectors measure the disappearance of reactor antineutrinos. The hardware trigger has to be very efficient for antineutrinos as well as for various types of background events. The triggering condition is based on discriminated PMT sum signals and the multiplicity of groups of PMTs. The talk gives an outlook to the double Chooz experiment and explains the requirements of the trigger system. The resulting concept and its performance is shown as well as first results from a prototype system.

  7. 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...

  8. 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...

  9. 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...

  10. Level-1 trigger selection of electrons and photons with CMS for LHC Run-II.

    CERN Document Server

    AUTHOR|(CDS)2088114

    2016-01-01

    The CMS experiment has a sophisticated two-level online selection system that achieves a rejection factor of nearly $10^5$. The first, hardware-level trigger (L1) is based on coarse information coming from the calorimeters and the muon detectors while the High-Level Trigger combines fine-grain information from all subdetectors. During Run II, the LHC will increase its center of mass energy to 13 or 14 TeV, and progressively reach an instantaneous luminosity of $2\\times10^{34} \\mathrm{cm}^{-2}\\mathrm{s}^{-1}$. In order to guarantee a successful and ambitious physics programme in this intense environment, the CMS trigger and data acquisition system must be upgraded. The L1 calorimeter trigger hardware and architecture in particular has been redesigned to maintain the current thresholds even in presence of more demanding conditions (e.g., for electrons and photons) and improve the performance for the selection of $\\tau$ leptons. This design benefits from recent $\\mu$TCA technology, allowing sophisticated algorit...

  11. Luminosity, beam monitoring and triggering for the CMS experiment and measurement of the total inelastic cross-section at √s = 7 TeV

    CERN Document Server

    Bell, Alan James

    The Compact Muon Solenoid (CMS) detector, situated on the Large Hadron Collider (LHC) ring is a multi-purpose detector designed to search for new physics phenomena, make precise measurements of known processes at previously untapped energies and look for hints of physics beyond the Standard Model. During the initial low luminosity stages, the Beam Scintillation Counter (BSC) sub-detector was vital in providing accurate and efficient ( 98%) triggering of beam halo and minimum bias events and helped in the commissioning of the CMS detector. This thesis is given in three parts. The first section describes the design and implementation of the BSC and the commissioning of the system before and during the early operation of the LHC. Analysis of the technical triggers it provided, using early low pile-up data in shown to demonstrate that the goal of providing an efficient trigger for low luminosities was achieved. Demonstrations of its use beyond its intended design are also shown, which helped drive the need for an...

  12. 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.

  13. UA1 upgrade first-level calorimeter trigger processor

    International Nuclear Information System (INIS)

    Bains, N.; Charlton, D.; Ellis, N.; Garvey, J.; Gregory, J.; Jimack, M.P.; Jovanovic, P.; Kenyon, I.R.; Baird, S.A.; Campbell, D.; Cawthraw, M.; Coughlan, J.; Flynn, P.; Galagedera, S.; Grayer, G.; Halsall, R.; Shah, T.P.; Stephens, R.; Eisenhandler, E.; Fensome, I.; Landon, M.

    1989-01-01

    A new first-level trigger processor has been built for the UA1 experiment on the Cern SppS Collider. The processor exploits the fine granularity of the new UA1 uranium-TMP calorimeter to improve the selectivity of the trigger. The new electron trigger has improved hadron jet rejection, achieved by requiring low energy deposition around the electromagnetic cluster. A missing transverse energy trigger and a total energy trigger have also been implemented. (orig.)

  14. The ATLAS Trigger Menu Design for Higher Luminosities in Run-2

    CERN Document Server

    Wiglesworth, Craig; The ATLAS collaboration

    2018-01-01

    In this presentation we describe the design criteria for the trigger menu for Run-2. We discuss several aspects of the process of planning the trigger menu, starting from how ATLAS physics goals and the need for detector performance measurements enter the menu design, and how rate, bandwidth, and CPU constraints are folded in during the compilation of the menu. We present the tools that allow us to predict and optimize the trigger rates and CPU consumption for the anticipated LHC luminosities. We outline the online system that we implemented to monitor deviations from the individual trigger target rates and to quickly react to changing LHC conditions and data taking scenarios. Finally we give an overview of the updated 2E34 Trigger Menu, allowing the listener to get a taste of the vast physics program that the trigger is supporting.

  15. PHYSICS

    CERN Multimedia

    P. Sphicas

    There have been three physics meetings since the last CMS week: “physics days” on March 27-29, the Physics/ Trigger week on April 23-27 and the most recent physics days on May 22-24. The main purpose of the March physics days was to finalize the list of “2007 analyses”, i.e. the few topics that the physics groups will concentrate on for the rest of this calendar year. The idea is to carry out a full physics exercise, with CMSSW, for select physics channels which test key features of the physics objects, or represent potential “day 1” physics topics that need to be addressed in advance. The list of these analyses was indeed completed and presented in the plenary meetings. As always, a significant amount of time was also spent in reviewing the status of the physics objects (reconstruction) as well as their usage in the High-Level Trigger (HLT). The major event of the past three months was the first “Physics/Trigger week” in Apri...

  16. NaNet-10: a 10GbE network interface card for the GPU-based low-level trigger of the NA62 RICH detector

    International Nuclear Information System (INIS)

    Ammendola, R.; Biagioni, A.; Frezza, O.; Lonardo, A.; Cicero, F. Lo; Martinelli, M.; Paolucci, P.S.; Pastorelli, E.; Simula, F.; Tosoratto, L.; Vicini, P.; Fiorini, M.; Neri, I.; Lamanna, G.; Piandani, R.; Pontisso, L.; Sozzi, M.; Rossetti, D.

    2016-01-01

    A GPU-based low level (L0) trigger is currently integrated in the experimental setup of the RICH detector of the NA62 experiment to assess the feasibility of building more refined physics-related trigger primitives and thus improve the trigger discriminating power. To ensure the real-time operation of the system, a dedicated data transport mechanism has been implemented: an FPGA-based Network Interface Card (NaNet-10) receives data from detectors and forwards them with low, predictable latency to the memory of the GPU performing the trigger algorithms. Results of the ring-shaped hit patterns reconstruction will be reported and discussed

  17. Experience of Percutaneous Trigger Finger Release under Local ...

    African Journals Online (AJOL)

    New Delhi, India. ... This procedure is easy, quicker, less complications and economical with good results. ... Sahu and Gupta: Trigger finger release under local anesthesia .... the most cost-effective treatment is two trials of corticosteroid.

  18. Simulation of the ATLAS New Small Wheel trigger

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00399900; The ATLAS collaboration

    2018-01-01

    The instantaneous luminosity of the LHC will increase up to a factor of seven with respect to the original design value to explore physics at higher energy scale. The inner station of the ATLAS muon end-cap system (Small Wheel) will be replaced by the New Small Wheel (NSW) to benefit from the high luminosity. The NSW will provide precise track-segment information to the Level-1 trigger system in order to suppress the trigger rate from fake muon tracks. This article summarizes the NSW trigger decision system and track-segment finding algorithm implemented in the trigger processor, and discusses results of performance studies on the trigger system. The results demonstrate that the NSW trigger system is capable of working with good performance satisfying the requirements.

  19. 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.

  20. The VZERO detector, the present muon physics and its future with the ALICE experiment at the LHC

    International Nuclear Information System (INIS)

    Tieulent, R.

    2013-01-01

    The ALICE experiment studies the Pb-Pb or proton-Pb or proton-proton collisions at the LHC to assess the fundamental features of the quark-gluon plasma (QGP). A brief introduction to QGP and physics of heavy ions is given in the first chapter. A detector named VZERO composed of 2 hodoscopes made up of organic scintillators located on either side of the collision point has been designed. The main purpose of VZERO is to provide the triggering signal for the ALICE experiment and to provide a second triggering signal sensitive to the energy density released in the collision. VZERO is described in the second chapter. QGP can be studied through various observables. The muons is one of the most promising as the production of muons appears at any stage of the QGP evolution and the muons can be detected easily as they do interact weakly with the plasma. The muon spectrometer and its alignment system are described in the chapter 3. The vector mesons of low mass like for instance the ρ meson are sensitive to the medium effect and to the restoration of the Chiral symmetry. The Chiral symmetry is spontaneously broken in QCD at normal energy and density ranges but the restoration of the Chiral symmetry is predicted by QCD calculus at the temperatures reached by LHC. The study of low mass vector mesons is described in the fourth chapter. A new step forward for the ALICE experiment is being prepared in order to benefit fully with the increase of both luminosity and energy of the LHC in 2018. A new detector based on silicon pixels: the Muon Forward Tracker (MFT) is being designed. The experimental data of the muon spectrometer combined with those of the MFT will open a new road for muon physics. The last chapter is dedicated to the MFT

  1. Design choices and issues in fixed-target B experiments

    International Nuclear Information System (INIS)

    Camilleri, L.

    1993-01-01

    The main priority of any experiment on B physics in the years to come will be an endeavour to observe CP violation in the B sector. Such measurements imply the following requirements of the experiment. Trigger: a muon trigger will be sensitive to J/ψ reactions and muon tags; an electron trigger will double the number of lepton events; in order to include kaon tags and self-tagging reactions, the experiment must not rely entirely on lepton triggers. Secondary Vertex triggers and hadron p T triggers should be included in order to have the maximum flexibility. Detector: vertex detector; particle identification; good momentum resolution; electromagnetic and hadronic calorimeters; muon detector. In addition the following issues have to be addressed: Collider or fixed-target mode? If fixed target, extracted beam or internal target? If internal target, gas jet or wire target? If a gas jet, hydrogen or a heavy gas? Beam pipe design. Silicon microvertex design and radiation damage. K s 0 decay path. Particle identification. Momentum resolution. Order of detectors. No single method stands out as the open-quotes obvious one.close quotes An extracted beam yields better vertex resolution and an internal target easier triggering. A flexible and diverse triggering scheme is of prime importance in order to be sensitive to as many reactions as possible, the experiment should not be limited to lepton triggers only. Proposed experiments (P867, HERA B) at existing machines will be invaluable for testing new devices and strategies for the LHC and SSC experiments

  2. The second level trigger system of FAST

    CERN Document Server

    Martínez,G; Berdugo, J; Casaus, J; Casella, V; De Laere, D; Deiters, K; Dick, P; Kirkby, J; Malgeri, L; Mañá, C; Marín, J; Pohl, M; Petitjean, C; Sánchez, E; Willmott, C

    2009-01-01

    The Fibre Active Scintillator Target (FAST) experiment is a novel imaging particle detector currently operating in a high-intensity π+ beam at the Paul Scherrer Institute (PSI), Villigen, Switzerland. The detector is designed to perform a high precision measurement of the μ+ lifetime, in order to determine the Fermi constant, Gf, to 1 ppm precision. A dedicated second level (LV2) hardware trigger system has been developed for the experiment. It performs an online analysis of the π/μ decay chain by identifying the stopping position of each beam particle and detecting the subsequent appearance of the muon. The LV2 trigger then records the muon stop pixel and selectively triggers the Time-to-Digital Converters (TDCs) in the vicinity. A detailed description of the trigger system is presented in this paper.

  3. Operation and Performance of a new microTCA-based CMS Calorimeter Trigger in LHC Run 2

    CERN Document Server

    Klabbers, Pamela Renee

    2016-01-01

    The Large Hadron Collider (LHC) at CERN is currently increasing the instantaneous luminosity for p-p collisions. In LHC Run 2, the center-of-mass energy has gone from 8 to 13 TeV and the instantaneous luminosity will approximately double for proton collisions. This will make it even more challenging to trigger on interesting events since the number of interactions per crossing (pileup) and the overall trigger rate will be significantly larger than in LHC Run 1. The Compact Muon Solenoid (CMS) experiment has installed the second stage of a two-stage upgrade to the Calorimeter Trigger to ensure that the trigger rates can be controlled and the thresholds kept low, so that physics data will not be compromised. The stage-1, which replaced the original CMS Global Calorimeter Trigger, operated successfully in 2015. The completely new stage-2 has replaced the entire calorimeter trigger in 2016 with AMC form-factor boards and optical links operating in a microTCA chassis. It required that updates to the calorimet...

  4. The CMS electron and photon trigger for the LHC Run 2

    CERN Document Server

    Beschi, Andrea

    2017-01-01

    to optimally reconstruct the electromagnetic trigger objects. The performance of the new trigger system will be presented, based on proton-proton collision data collected in Run II. The selection techniques used to trigger efficiently will be presented, along with the strategies employed to guarantee efficient triggering for new resonances and other new physics signals invo...

  5. 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...

  6. The ATLAS Muon Trigger Performance : Run 1 and initial Run 2.

    CERN Document Server

    Kasahara, Kota; The ATLAS collaboration

    2015-01-01

    The ATLAS Muon Trigger Performance: Run 1 and Initial Run 2 Performance

Events with muons in the final state are an important signature for many physics topics at the Large Hadron Collider (LHC). An efficient trigger on muons and a detailed understanding of its performance are required. In 2012, the last year of Run 1, the instantaneous luminosity of the LHC reached 7.7x10^33 cm -2s-1 and the average number of events that occur in a same bunch crossing was 25. The ATLAS Muon trigger has successfully adapted to this changing environment by making use of isolation requirements, combined trigger signatures with electron and jet trigger objects, and by using so-called full-scan triggers, which make use of the full event information to search for di-lepton signatures, seeded by single lepton objects. A stable and highly efficient muon trigger was vital in the discovery of Higgs boson in 2012 and for many searches for new physics. 
The performance of muon triggers during the LHC Run 1 data-taking campaigns i...

  7. 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...

  8. Physically based modeling of rainfall-triggered landslides: a case study in the Luquillo forest, Puerto Rico

    Science.gov (United States)

    Lepore, C.; Arnone, E.; Noto, L. V.; Sivandran, G.; Bras, R. L.

    2013-09-01

    This paper presents the development of a rainfall-triggered landslide module within an existing physically based spatially distributed ecohydrologic model. The model, tRIBS-VEGGIE (Triangulated Irregular Networks-based Real-time Integrated Basin Simulator and Vegetation Generator for Interactive Evolution), is capable of a sophisticated description of many hydrological processes; in particular, the soil moisture dynamics are resolved at a temporal and spatial resolution required to examine the triggering mechanisms of rainfall-induced landslides. The validity of the tRIBS-VEGGIE model to a tropical environment is shown with an evaluation of its performance against direct observations made within the study area of Luquillo Forest. The newly developed landslide module builds upon the previous version of the tRIBS landslide component. This new module utilizes a numerical solution to the Richards' equation (present in tRIBS-VEGGIE but not in tRIBS), which better represents the time evolution of soil moisture transport through the soil column. Moreover, the new landslide module utilizes an extended formulation of the factor of safety (FS) to correctly quantify the role of matric suction in slope stability and to account for unsaturated conditions in the evaluation of FS. The new modeling framework couples the capabilities of the detailed hydrologic model to describe soil moisture dynamics with the infinite slope model, creating a powerful tool for the assessment of rainfall-triggered landslide risk.

  9. Physically based modeling of rainfall-triggered landslides: a case study in the Luquillo forest, Puerto Rico

    Directory of Open Access Journals (Sweden)

    C. Lepore

    2013-09-01

    Full Text Available This paper presents the development of a rainfall-triggered landslide module within an existing physically based spatially distributed ecohydrologic model. The model, tRIBS-VEGGIE (Triangulated Irregular Networks-based Real-time Integrated Basin Simulator and Vegetation Generator for Interactive Evolution, is capable of a sophisticated description of many hydrological processes; in particular, the soil moisture dynamics are resolved at a temporal and spatial resolution required to examine the triggering mechanisms of rainfall-induced landslides. The validity of the tRIBS-VEGGIE model to a tropical environment is shown with an evaluation of its performance against direct observations made within the study area of Luquillo Forest. The newly developed landslide module builds upon the previous version of the tRIBS landslide component. This new module utilizes a numerical solution to the Richards' equation (present in tRIBS-VEGGIE but not in tRIBS, which better represents the time evolution of soil moisture transport through the soil column. Moreover, the new landslide module utilizes an extended formulation of the factor of safety (FS to correctly quantify the role of matric suction in slope stability and to account for unsaturated conditions in the evaluation of FS. The new modeling framework couples the capabilities of the detailed hydrologic model to describe soil moisture dynamics with the infinite slope model, creating a powerful tool for the assessment of rainfall-triggered landslide risk.

  10. Physics Experiments at the UNEDLabs Portal

    Directory of Open Access Journals (Sweden)

    Juan pedro Sánchez

    2012-01-01

    Full Text Available UNEDLabs is a web portal based on a free, modern, open source, and well-known learning management system: Moodle. This portal joins two theme networks of virtual and remote laboratories (one for Control Engineering and another one for Physics, named AutomatL@bs and FisL@bs, respectively together. AutomatL@bs has been operative for five years now. Following AutomatL@bs’ scheme, FisL@bs was created as a network of remote and virtual laboratories for physics university education via the Internet to offer students the possibility of performing hands-on experiences in different fields of physics in two ways: simulation and real remote operation. Now, both FisL@bs and AutomatL@bs join together (while maintaining their independency into an unique new web portal called UNEDLabs. This work focuses on this new web environment and gives a detailed account of a novel way in Physics to let distance learning students gain practical experience autonomously. This paper explains how the new portal works and the software tools used for creating it. In addition, it also describes the physics experiments which are already operative.

  11. A trigger card for event rejection in the RMC experiment at TRIUMF

    International Nuclear Information System (INIS)

    Bennett, P.; Chan, R.; Daviel, S.; Ko, S.; Blecher, M.; Hasinoff, M.; Sample, D.; Wright, D.; Poutissou, R.

    1990-01-01

    A trigger card has been designed and constructed to improve the trigger efficiency of a large solid angle pair spectrometer to be used for the measurement of radiative muon capture at TRIUMF. A number of these trigger cards are connected to FASTBUS pipeline TDCs via the FASTBUS auxiliary connector, to provide coarse information on the tracks of charged particles in a drift chamber. The trigger cards produce a majority OR of groups of six signals from the chamber, allowing very fast on-line event rejection. The performance of the cards and other relevant technical issues will be discussed in this article

  12. The Level-0 Muon Trigger for the LHCb experiment

    CERN Document Server

    Aslanides, E; Cogan, J; Duval, P Y; Le Gac, R; Leroy, O; Liotard, PL; Marin, F; Favard, S; Tsaregorodtsev, A

    2006-01-01

    The Level-0 Muon Trigger looks for straight tracks crossing the five muon stations of the LHCb muon detector and measures their transverse momentum. The tracking uses a road algorithm relying on the projectivity of the muon detector. The architecture of the Level-0 muon trigger is pipeline and massively parallel. Receiving 130 GBytes/s of input data, it reconstructs muon candidates for each bunch crossing (25 ns) in less than 1.2 $\\mu$S. It relies on an intensive use of high speed multigigabit serial links where high speed serializers/deserializers are embedded in Field Programmable Gate Arrays (FPGAs).

  13. Frequency-Dependent Tidal Triggering of Low Frequency Earthquakes Near Parkfield, California

    Science.gov (United States)

    Xue, L.; Burgmann, R.; Shelly, D. R.

    2017-12-01

    The effect of small periodic stress perturbations on earthquake generation is not clear, however, the rate of low-frequency earthquakes (LFEs) near Parkfield, California has been found to be strongly correlated with solid earth tides. Laboratory experiments and theoretical analyses show that the period of imposed forcing and source properties affect the sensitivity to triggering and the phase relation of the peak seismicity rate and the periodic stress, but frequency-dependent triggering has not been quantitatively explored in the field. Tidal forcing acts over a wide range of frequencies, therefore the sensitivity to tidal triggering of LFEs provides a good probe to the physical mechanisms affecting earthquake generation. In this study, we consider the tidal triggering of LFEs near Parkfield, California since 2001. We find the LFEs rate is correlated with tidal shear stress, normal stress rate and shear stress rate. The occurrence of LFEs can also be independently modulated by groups of tidal constituents at semi-diurnal, diurnal and fortnightly frequencies. The strength of the response of LFEs to the different tidal constituents varies between LFE families. Each LFE family has an optimal triggering frequency, which does not appear to be depth dependent or systematically related to other known properties. This suggests the period of the applied forcing plays an important role in the triggering process, and the interaction of periods of loading history and source region properties, such as friction, effective normal stress and pore fluid pressure, produces the observed frequency-dependent tidal triggering of LFEs.

  14. Continuously live image processor for drift chamber track segment triggering

    International Nuclear Information System (INIS)

    Berenyi, A.; Chen, H.K.; Dao, K.

    1999-01-01

    The first portion of the BaBar experiment Level 1 Drift Chamber Trigger pipeline is the Track Segment Finder (TSF). Using a novel method incorporating both occupancy and drift-time information, the TSF system continually searches for segments in the supercells of the full 7104-wire Drift Chamber hit image at 3.7 MHz. The TSF was constructed to operate in a potentially high beam-background environment while achieving high segment-finding efficiency, deadtime-free operation, a spatial resolution of 5 simulated physics events

  15. 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.

  16. Testing for the 'predictability' of dynamically triggered earthquakes in The Geysers geothermal field

    Science.gov (United States)

    Aiken, Chastity; Meng, Xiaofeng; Hardebeck, Jeanne

    2018-03-01

    The Geysers geothermal field is well known for being susceptible to dynamic triggering of earthquakes by large distant earthquakes, owing to the introduction of fluids for energy production. Yet, it is unknown if dynamic triggering of earthquakes is 'predictable' or whether dynamic triggering could lead to a potential hazard for energy production. In this paper, our goal is to investigate the characteristics of triggering and the physical conditions that promote triggering to determine whether or not triggering is in anyway foreseeable. We find that, at present, triggering in The Geysers is not easily 'predictable' in terms of when and where based on observable physical conditions. However, triggered earthquake magnitude positively correlates with peak imparted dynamic stress, and larger dynamic stresses tend to trigger sequences similar to mainshock-aftershock sequences. Thus, we may be able to 'predict' what size earthquakes to expect at The Geysers following a large distant earthquake.

  17. 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.

  18. The CMS Electromagnetic Trigger: commissioning and performance toward the start of operation

    International Nuclear Information System (INIS)

    Zabi, A.

    2009-01-01

    The CMS electromagnetic calorimeter (ECAL) has been designed to precisely measure electron and photon energy. It is made of 75848 lead tungstate (PbWO 4 ) crystals and its characteristics have been optimized for the search of the Higgs boson in its two photons decay mode. In view of the high interaction rate at the Large Hadron Collider (Lhc), CMS implements a sophisticated online selection system that achieves a rejection factor of nearly 10 6 . In the intense hadronic environment, the ECAL trigger system provides a powerful tool to select interesting physics events which may contain electrons or photons in their final states. Comic ray data recorded by the CMS experiment have been analyzed in order to estimate the ECAL trigger performance in terms of efficiency.

  19. 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...

  20. GPU-based low-level trigger system for the standalone reconstruction of the ring-shaped hit patterns in the RICH Cherenkov detector of NA62 experiment

    International Nuclear Information System (INIS)

    Ammendola, R.; Biagioni, A.; Cretaro, P.; Frezza, O.; Cicero, F. Lo; Lonardo, A.; Martinelli, M.; Paolucci, P.S.; Pastorelli, E.; Chiozzi, S.; Ramusino, A. Cotta; Fiorini, M.; Gianoli, A.; Neri, I.; Lorenzo, S. Di; Fantechi, R.; Piandani, R.; Pontisso, L.; Lamanna, G.; Piccini, M.

    2017-01-01

    This project aims to exploit the parallel computing power of a commercial Graphics Processing Unit (GPU) to implement fast pattern matching in the Ring Imaging Cherenkov (RICH) detector for the level 0 (L0) trigger of the NA62 experiment. In this approach, the ring-fitting algorithm is seedless, being fed with raw RICH data, with no previous information on the ring position from other detectors. Moreover, since the L0 trigger is provided with a more elaborated information than a simple multiplicity number, it results in a higher selection power. Two methods have been studied in order to reduce the data transfer latency from the readout boards of the detector to the GPU, i.e., the use of a dedicated NIC device driver with very low latency and a direct data transfer protocol from a custom FPGA-based NIC to the GPU. The performance of the system, developed through the FPGA approach, for multi-ring Cherenkov online reconstruction obtained during the NA62 physics runs is presented.

  1. Development of the jet Feature EXtractor (jFEX) for the ATLAS Level 1 calorimeter trigger upgrade at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00547698; The ATLAS collaboration; Brogna, Andrea Salvatore; Buescher, Volker; Degele, Reinhold; Herr, Holger; Kahra, Christian; Rave, Stefan; Rocco, Elena; Schaefer, Uli; Vieira De Souza, Julio; Tapprogge, Stefan; Bauss, Bruno

    2017-01-01

    To cope with the enhanced luminosity delivered by the Large Hadron Collider from 2021 onwards, the ATLAS experiment has planned several upgrades. The first level trigger based on calorimeter data will be upgraded to exploit fine-granularity readout using a new system of Feature EXtractors (FEXs, FPGA-based trigger boards), each optimized to trigger on different physics objects. This contribution is focused on the jet FEX. The main challenges of such a board are the input bandwidth of up to 3.1 Tbps, dense routing of high-speed signals and power consumption. The design, PCB simulations and results of integrated tests of a prototype are shown in this document.

  2. Performance of the NOνA Data Acquisition and Trigger Systems for the full 14 kT Far Detector

    International Nuclear Information System (INIS)

    Norman, A.; Ding, P.F.; Rebel, B.; Shanahan, P.; Davies, G.S.; Niner, E.; Dukes, E.C.; Frank, M.J.; Group, R.C.; Henderson, W.; Mina, R.; Oksuzian, Y.; Duyan, H.; Habig, A.; Moren, A.; Tomsen, K.; Mualem, L.; Sheshukov, A.; Tamsett, M.; Vinton, L.

    2015-01-01

    The NOvA experiment uses a continuous, free-running, dead-timeless data acquisition system to collect data from the 14 kT far detector. The DAQ system readouts the more than 344,000 detector channels and assembles the information into an raw unfiltered high bandwidth data stream. The NOvA trigger systems operate in parallel to the readout and asynchronously to the primary DAQ readout/event building chain. The data driven triggering systems for NOvA are unique in that they examine long contiguous time windows of the high resolution readout data and enable the detector to be sensitive to a wide range of physics interactions from those with fast, nanosecond scale signals up to processes with long delayed coincidences between hits which occur at the tens of milliseconds time scale. The trigger system is able to achieve a true 100% live time for the detector, making it sensitive to both beam spill related and off-spill physics. (paper)

  3. Hadronic Triggers and trigger-object level analysis at ATLAS

    CERN Document Server

    Zaripovas, Donatas Ramilas; The ATLAS collaboration

    2017-01-01

    Hadronic signatures are critical to the high energy physics analysis program, and are broadly used for both Standard Model measurements and searches for new physics. These signatures include generic quark and gluon jets, as well as jets originating from b-quarks or the decay of massive particles (such as electroweak bosons or top quarks). Additionally missing transverse momentum from non-interacting particles provides an interesting probe in the search for new physics beyond the Standard Model. Developing trigger selections that target these events is a huge challenge at the LHC due to the enormous rates associated with these signatures. This challenge is exacerbated by the amount of pile-up activity, which continues to grow. In order to address these challenges, several new techniques have been developed during the past year in order to significantly improve the potential of the 2017 dataset and overcome the limiting factors to more deeply probing for new physics, such as storage and computing requirements f...

  4. The second level trigger system of FAST

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, G. [CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain)], E-mail: gustavo.martinez@ciemat.es; Barcyzk, A. [CERN, CH-1211 Geneva 23 (Switzerland); Berdugo, J.; Casaus, J. [CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain); Casella, C.; De Laere, S. [Universite de Geneve, 30 quai Ernest-Anserment, CH-1211 Geneva 4 (Switzerland); Deiters, K.; Dick, P. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Kirkby, J.; Malgeri, L. [CERN, CH-1211 Geneva 23 (Switzerland); Mana, C.; Marin, J. [CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain); Pohl, M. [Universite de Geneve, 30 quai Ernest-Anserment, CH-1211 Geneva 4 (Switzerland); Petitjean, C. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Sanchez, E.; Willmott, C. [CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain)

    2009-10-11

    The Fibre Active Scintillator Target (FAST) experiment is a novel imaging particle detector currently operating in a high-intensity {pi}{sup +} beam at the Paul Scherrer Institute (PSI), Villigen, Switzerland. The detector is designed to perform a high precision measurement of the {mu}{sup +} lifetime, in order to determine the Fermi constant, G{sub f}, to 1 ppm precision. A dedicated second level (LV2) hardware trigger system has been developed for the experiment. It performs an online analysis of the {pi}/{mu} decay chain by identifying the stopping position of each beam particle and detecting the subsequent appearance of the muon. The LV2 trigger then records the muon stop pixel and selectively triggers the Time-to-Digital Converters (TDCs) in the vicinity. A detailed description of the trigger system is presented in this paper.

  5. ALICE High Level Trigger

    CERN Multimedia

    Alt, T

    2013-01-01

    The ALICE High Level Trigger (HLT) is a computing farm designed and build for the real-time, online processing of the raw data produced by the ALICE detectors. Events are fully reconstructed from the raw data, analyzed and compressed. The analysis summary together with the compressed data and a trigger decision is sent to the DAQ. In addition the reconstruction of the events allows for on-line monitoring of physical observables and this information is provided to the Data Quality Monitor (DQM). The HLT can process event rates of up to 2 kHz for proton-proton and 200 Hz for Pb-Pb central collisions.

  6. The Atlas pulsed power facility for high energy density physics experiments

    CERN Document Server

    Miller, R B; Barr, G W; Bowman, D W; Cochrane, J C; Davis, H A; Elizondo, J M; Gribble, R F; Griego, J R; Hicks, R D; Hinckley, W B; Hosack, K W; Nielsen, K E; Parker, J V; Parsons, M O; Rickets, R L; Salazar, H R; Sánchez, P G; Scudder, D W; Shapiro, C; Thompson, M C; Trainor, R J; Valdez, G A; Vigil, B N; Watt, R G; Wysocki, F J; Kirbie, H C

    1999-01-01

    The Atlas facility, now under construction at Los Alamos National Laboratory (LANL), will provide a unique capability for performing high-energy-density experiments in support of weapon-physics and basic-research programs. Here, the authors describe how the primary element of Atlas is a 23-MJ capacitor bank, comprised of 96 separate Marx generators housed in 12 separate oil-filled tanks, surrounding a central target chamber. Each tank will house two, independently- removable maintenance units, with each maintenance unit consisting of four Marx modules. Each Marx module has four capacitors that can each be charged to a maximum of 60 kilovolts. When railgap switches are triggered, the Marx modules erect to a maximum of 240 kV. The parallel discharge of these 96 Marx modules will deliver a 30-MA current pulse with a 4-5-ys risetime to a cylindrical, imploding liner via 24 vertical, tri-plate, oil-insulated transmission lines. An experimental program for testing and certifying all Marx and transmission line compo...

  7. Software trigger for the TOPAZ detector at TRISTAN

    International Nuclear Information System (INIS)

    Tsukamoto, T.; Yamauchi, M.; Enomoto, R.

    1990-01-01

    A new software trigger system was developed and installed at the TOPAZ detector to the trigger system for the TRISTAN e + e - collider to take data efficiently in the scheduled high luminosity experiment. This software trigger requires two or more charged tracks originated at the interaction point by examining the timing of signals from the time projection chamber. To execute the vertex finding very quickly, four microprocessors are used in parallel. By this new trigger the rate of the track trigger was reduced down to 30-40% with very small inefficiency. The additional dead time by this trigger is negligible. (orig.)

  8. Testing for the ‘predictability’ of dynamically triggered earthquakes in Geysers Geothermal Field

    Science.gov (United States)

    Aiken, Chastity; Meng, Xiaofeng; Hardebeck, Jeanne L.

    2018-01-01

    The Geysers geothermal field is well known for being susceptible to dynamic triggering of earthquakes by large distant earthquakes, owing to the introduction of fluids for energy production. Yet, it is unknown if dynamic triggering of earthquakes is ‘predictable’ or whether dynamic triggering could lead to a potential hazard for energy production. In this paper, our goal is to investigate the characteristics of triggering and the physical conditions that promote triggering to determine whether or not triggering is in anyway foreseeable. We find that, at present, triggering in The Geysers is not easily ‘predictable’ in terms of when and where based on observable physical conditions. However, triggered earthquake magnitude positively correlates with peak imparted dynamic stress, and larger dynamic stresses tend to trigger sequences similar to mainshock–aftershock sequences. Thus, we may be able to ‘predict’ what size earthquakes to expect at The Geysers following a large distant earthquake.

  9. DYN1: a 66 MHz front end analog memory chip with first level trigger capture for use in future high luminosity particle physics experiments

    International Nuclear Information System (INIS)

    Anghinolfi, F.; Aspell, P.; Bonino, R.; Campbell, D.; Campbell, M.; Clark, A.G.; Heijne, E.H.M.; Jarron, P.; Santiard, J.C.; Verweij, H.

    1994-01-01

    DYN1 is a 32 channel, 128 cell analog memory with continuous write and read access. The chip amplifies the detector signals and integrates the signal currents onto capacitors within the memory during each bunch crossing interval. Dense dynamic logic circuitry accepts multiple first level triggers, freezes the corresponding analog data and stores their addresses in an external FIFO. The triggered data can then be read out at leisure whilst simultaneously sampling and storing new triggered events. A first level trigger latency of up to 2 μs is accepted at the maximum LHC clock frequency of 66 MHz. The chip shows an overall gain of 48.2 mV/25 000 e - . The mean channel noise is 4.5 mV and the pedestal variation from cell to cell within one channel is 1.9 mV. The total dynamic range has been measured at 4.6 V giving a resolution of 11 bits (0.05%) for the memory itself. (orig.)

  10. Current experiments in elementary particle physics. Revised

    Energy Technology Data Exchange (ETDEWEB)

    Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)

    1992-06-01

    This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  11. 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...

  12. Fast Tracker (FTK): A Hardware Track Finder for the ATLAS Trigger

    CERN Document Server

    Mitani, Takashi; The ATLAS collaboration

    2015-01-01

    During the 2010-2012 run of Large Hadron Collider experiment, the ATLAS trigger system was successfully operated and it contributed to several important results such as observation of Higgs boson with a mass of about 125 GeV. From 2015, collision energy will increase to 13-14 TeV and its instantaneous luminosity will reach $1$-$2\\times10^{34}$cm$^{-2}$s$^{-1}$ with a 25 ns bunch crossing period. Due to the energy increase, the cross sections for SM processes are expected to get much larger. Additionally, the number of overlapping proton-proton interactions per bunch crossing, which is refereed to as pile-up, is expected to increase significantly up to about 80. Therefore it will be challenging to control trigger rates while keeping good efficiency for interesting physics events. This document summarizes the development of Fast Tracker and its tracking performance for the ATLAS experiment. The Fast Tracker is a custom electronics system that will operate at the full Level 1 accepted rate of 100 kHz and provide...

  13. The ATLAS Muon Trigger Performance : Run 1 and initial Run 2.

    CERN Document Server

    Kasahara, Kota; The ATLAS collaboration

    2015-01-01

    Events with muons in the final state are an important signature for many physics topics at the Large Hadron Collider (LHC). An efficient trigger on muons and a detailed understanding of its performance are required. In 2012, the last year of Run 1, the instantaneous luminosity of the LHC reached 7.7x10^33 cm -2s-1 and the average number of events that occur in a same bunch crossing was 25. The ATLAS Muon trigger has successfully adapted to this changing environment by making use of isolation requirements, combined trigger signatures with electron and jet trigger objects, and by using so-called full-scan triggers, which make use of the full event information to search for di-lepton signatures, seeded by single lepton objects. A stable and highly efficient muon trigger was vital in the discovery of Higgs boson in 2012 and for many searches for new physics. 
The performance of muon triggers during the LHC Run 1 data-taking campaigns is presented, together with an overview and preliminary results of the new muo...

  14. Timing calibration of the trigger system for the drift tube detector of the OPERA neutrino oscillation experiment

    International Nuclear Information System (INIS)

    Lenkeit, Jan

    2015-11-01

    The OPERA experiment searches for ν μ → ν τ oscillations in an almost pure ν μ beam. The goal is to observe the oscillations in appearance mode by using a large-scale lead/emulsion target to resolve individual ν τ interactions. Magnetic spectrometers measure the charge and momentum of beam induced muons leaving the target sections. The Precision Tracker, a drift tube detector consisting of almost 10000 drift tubes, provides the tracking information inside the spectrometers. The coordinate measurement in the drift tubes is derived from a time measurement relative to an external trigger signal. In order to reach the required momentum resolution of less than 25 % for particle momenta up to 25 GeV, the uncertainty on the trigger timing must not exceed a value of 5 ns. In this thesis, a procedure for the timing calibration of the trigger system is presented. A step-by-step calibration of the corresponding signal paths is described. Applying all calibration results, a spatial resolution of 255 μm is achieved for the Precision Tracker, meeting the specified requirements. Furthermore, a method using the calibrated trigger system for performing time of flight measurements with atmospheric muons is developed. The average error on the measured flight times is ±4.5 ns.

  15. Boosted object hardware trigger development and testing for the Phase I upgrade of the ATLAS Experiment

    CERN Document Server

    Stark, Giordon Holtsberg; The ATLAS collaboration

    2015-01-01

    The Global Feature Extraction (gFEX) module is a Level 1 jet trigger system planned for installation in ATLAS during the Phase 1 upgrade in 2018. The gFEX selects large-radius jets for capturing Lorentz-boosted objects by means of wide-area jet algorithms refined by subjet information. The architecture of the gFEX permits event-by-event local pile-up suppression for these jets using the same subtraction techniques developed for offline analyses. The gFEX architecture is also suitable for other global event algorithms such as missing transverse energy (MET), centrality for heavy ion collisions, and "jets without jets". The gFEX will use 4 processor FPGAs to perform calculations on the incoming data and a Hybrid APU-FPGA for slow control of the module. The gFEX is unique in both design and implementation and substantially enhance the selectivity of the L1 trigger and increases sensitivity to key physics channels.

  16. Test of a demonstrator of an MDT-based first-level muon Trigger for HL-LHC under realistic operating conditions

    CERN Document Server

    Kroha, Hubert; The ATLAS collaboration

    2015-01-01

    Highly selective first level triggers are essential for the physics programme of the ATLAS Experiment at the HL-LHC where the instantaneous luminosity will exceed the LHC’s instantaneous luminosity by almost an order of magnitude. The ATLAS first level muon trigger rate is dominated by low momentum sub-trigger threshold muons due to the limited momentum resolution at trigger level caused by the moderate spatial resolution of the resistive plate and thin gap trigger chambers. This limitation can be overcome by including the data of the precision muon drift tube chambers in the first level Trigger decision. This requires the implementation of a fast MDT read-out chain and a fast MDT track reconstruction. A hardware demonstrator of the fast read-out chain was successfully tested under HL-LHC operating conditions at CERN’s Gamma Irradiation Facility. It could be shown that the data provided by the demonstrator can be processed with a fast track reconstruction algorithm on an ARM CPU within the 6 microseconds ...

  17. ATLAS FTK: Fast Track Trigger

    CERN Document Server

    Volpi, Guido; The ATLAS collaboration

    2015-01-01

    An overview of the ATLAS Fast Tracker processor is presented, reporting the design of the system, its expected performance, and the integration status. The next LHC runs, with a significant increase in instantaneous luminosity, will provide a big challenge to the trigger and data acquisition systems of all the experiments. An intensive use of the tracking information at the trigger level will be important to keep high efficiency in interesting events, despite the increase in multiple p-p collisions per bunch crossing (pile-up). In order to increase the use of tracks within the High Level Trigger (HLT), the ATLAS experiment planned the installation of an hardware processor dedicated to tracking: the Fast TracKer (FTK) processor. The FTK is designed to perform full scan track reconstruction at every Level-1 accept. To achieve this goal, the FTK uses a fully parallel architecture, with algorithms designed to exploit the computing power of custom VLSI chips, the Associative Memory, as well as modern FPGAs. The FT...

  18. 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

  19. 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)

  20. CONCEPTUAL DESIGN REPORT FOR A FAST MUON TRIGGER

    Energy Technology Data Exchange (ETDEWEB)

    OBRIEN,E.; BASYE, A.; ISENHOWER, D.; JUMPER, D.; SPARKS, N.; TOWELL, R.; WATTS, C.; WOOD, J.; WRIGHT, R.; HAGGERTY, J.; LYNCH, D.; BARISH, K.; EYSER, K.O.; SETO, R.; HU, S.; LI, X.; ZHOU, S.; GLENN, A.; KINNEY, E.; KIRILUK, K.; NAGLE, J.; CHI, C.Y.; SIPPACH, W.; ZAJC. W.; BUTLER, C.; HE, X.; OAKLEY, C.; YING, J.; BLACKBURN, J.; CHIU, M.; PERDEKAMP, M.G.; KIM, Y.J.; KOSTER, J.; LAYTON, D.; MAKINS, N.; MEREDITH, B.; NORTHACKER, D.; PENG, J.-C.; SEIDL, R.; THORSLAND, E.; WADHAMS, S.; WILLIAMSON, S.; YANG, R.; HILL, J.; KEMPEL, T.; LAJOIE, J.; SLEEGE, G.; VALE, C.; WEI, F.; SAITO, N.; HONG, B.; KIM, B.; LEE, K.; LEE, K.S.; PARK, S.; SIM, K.-S.; AOKI, K.; DAIRAKU, S.; IMAI, K.; KARATSU, K.; MURAKAMI, T.; SATO, A.; SENZAKA, K.; SHOJI, K.; TANIDA, K.; BROOKS, M.; LEITCH, M.; ADAMS, J.; CARINGI, A.; FADEM, B.; IDE, J.; LICHTENWALNER, P.; FIELDS, D.; MAO, Y.; HAN, R.; BUNCE, G.; XIE, W.; FUKAO, Y.; TAKETANI, A.; KURITA, K.; MURATA, J.; (PHENIX COLLABORATION)

    2007-08-01

    This document is a Conceptual Design Report for a fast muon trigger for the PHENIX experiment that will enable the study of flavor separated quark and anti-quark spin polarizations in the proton. A powerful way of measuring these polarizations is via single spin asymmetries for W boson production in polarized proton-proton reactions. The measurement is done by tagging W{sup +} and W{sup -} via their decay into high transverse momentum leptons in the forward directions. The PHENIX experiment is capable of measuring high momentum muons at forward rapidity, but the current online trigger does not have sufficient rejection to sample the rare leptons fromW decay at the highest luminosities at the Relativistic Heavy Ion Collider (RHIC). This Report details the goals, design, R&D, and schedule for building new detectors and trigger electronics to use the full RHIC luminosity to make this critical measurement. The idea for W boson measurements in polarized proton-proton collisions at RHIC was first suggested by Jacques Soffer and Claude Bourrely in 1995. This prompted the RIKEN institute in Japan to supply funds to build a second muon arm for PHENIX (south muon arm). The existence of both a north and south muon arm makes it possible to utilize a Z{sup 0} sample to study and control systematic uncertainties which arise in the reconstruction of high momentum muons. This document has its origins in recommendations made by a NSAC Subcommittee that reviewed the U.S. Heavy Ion Physics Program in June 2004. Part of their Recommendation 1 was to 'Invest in near-term detector upgrades of the two large experiments, PHENIX and STAR'. In Recommendation 2 the subcommittee stated '- detector improvements proceed at a rate that allows a timely determination of the flavor dependence of the quark-antiquark sea polarization through W-asymmetry measurements' as we are proposing here. On September 13, 2004 DOE requested from BNL a report articulating a research plan for

  1. 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.

  2. Nuclear physics experiment at INS

    International Nuclear Information System (INIS)

    Sugimoto, Kenzo.

    1981-02-01

    Present activities at the Institute for Nuclear Study (INS) are presented. Selected topics are from recent experiments by use of the INS cyclotron, experiments at the Bevalac facility under the INS-LBL collaboration program, and preparatory works for the Numatron project, a new project for the high-energy heavy-ion physics. (author)

  3. The ATLAS Electron and Photon Trigger

    CERN Document Server

    Jones, Samuel David; The ATLAS collaboration

    2018-01-01

    ATLAS electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential to record signals for a wide variety of physics: from Standard Model processes to searches for new phenomena. To cope with ever-increasing luminosity and more challenging pile-up conditions at a centre-of-mass energy of 13 TeV, the trigger selections need to be optimized to control the rates and keep efficiencies high. The ATLAS electron and photon trigger performance in Run 2 will be presented, including both the role of the ATLAS calorimeter in electron and photon identification and details of new techniques developed to maintain high performance even in high pile-up conditions.

  4. 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...

  5. Trigger and data acquisition: The bytes start and stop here!

    International Nuclear Information System (INIS)

    Tschirhart, R.

    2010-01-01

    The modern trigger and data acquisition systems that instrument discovery experiments at the Large Hadron Collider (LHC) at CERN are very complex digital systems that select, reduce, and process enormous volumes of data in real-time to match the resources of state-of-the-art distributed computing available to researchers. Never before in particle physics have such powerful digital reconstruction and filtering systems been matched to a world-wide distributed system of computing of unprecedented scale. The goal of these massive aggregate computing systems is to extract as much physical information as possible from collision events at the LHC with well understood selection criteria and biases. Current strategies and future challenges in providing these aggregate real-time and offline computing systems are described.

  6. Performance of the ATLAS trigger system in 2015

    Energy Technology Data Exchange (ETDEWEB)

    Aaboud, M. [Univ. Mohamed Premier et LPTPM, Oujda (Morocco). Faculte des Sciences; Aad, G. [CPPM, Aix-Marseille Univ. et CNRS/IN2P3, Marseille (France); Abbott, B. [Oklahoma Univ., Norman, OK (United States). Homer L. Dodge Dept. of Physics and Astronomy; Collaboration: Atlas Collaboration; and others

    2017-05-15

    During 2015 the ATLAS experiment recorded 3.8 fb{sup -1} of proton-proton collision data at a centre-of-mass energy of 13 TeV. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton-proton collision data. (orig.)

  7. Performance of the ATLAS Trigger System in 2015

    CERN Document Server

    Aaboud, Morad; Abbott, Brad; Abdallah, Jalal; Abdinov, Ovsat; Abeloos, Baptiste; Aben, Rosemarie; AbouZeid, Ossama; Abraham, Nicola; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adachi, Shunsuke; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Affolder, Tony; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexopoulos, Theodoros; Alhroob, Muhammad; Ali, Babar; Aliev, Malik; Alimonti, Gianluca; Alison, John; Alkire, Steven Patrick; Allbrooke, Benedict; Allen, Benjamin William; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Alshehri, Azzah Aziz; Alstaty, Mahmoud; Alvarez Gonzalez, Barbara; Άlvarez Piqueras, Damián; Alviggi, Mariagrazia; Amadio, Brian Thomas; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anders, John Kenneth; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Angelidakis, Stylianos; Angelozzi, Ivan; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antel, Claire; Antonelli, Mario; Antonov, Alexey; Antrim, Daniel Joseph; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Armitage, Lewis James; Arnaez, Olivier; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Artz, Sebastian; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Augsten, Kamil; Avolio, Giuseppe; Axen, Bradley; Ayoub, Mohamad Kassem; Azuelos, Georges; Baak, Max; Baas, Alessandra; Baca, Matthew John; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Baines, John; Bajic, Milena; Baker, Oliver Keith; Baldin, Evgenii; Balek, Petr; Balestri, Thomas; Balli, Fabrice; Balunas, William Keaton; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Barak, Liron; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisits, Martin-Stefan; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska-Blenessy, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barranco Navarro, Laura; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Basalaev, Artem; Bassalat, Ahmed; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Bauce, Matteo; Bauer, Florian; Bawa, Harinder Singh; Beacham, James; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Bechtle, Philip; Beck, Hans~Peter; Becker, Kathrin; Becker, Maurice; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bedognetti, Matteo; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Janna Katharina; Bell, Andrew Stuart; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Belyaev, Nikita; Benary, Odette; Benchekroun, Driss; Bender, Michael; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez, Jose; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Beresford, Lydia; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Beringer, Jürg; Berlendis, Simon; Bernard, Nathan Rogers; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertram, Iain Alexander; Bertsche, Carolyn; Bertsche, David; Besjes, Geert-Jan; Bessidskaia Bylund, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethani, Agni; Bethke, Siegfried; Bevan, Adrian John; Bianchi, Riccardo-Maria; Bianco, Michele; Biebel, Otmar; Biedermann, Dustin; Bielski, Rafal; Biesuz, Nicolo Vladi; Biglietti, Michela; Bilbao De Mendizabal, Javier; Billoud, Thomas Remy Victor; Bilokon, Halina; Bindi, Marcello; Bingul, Ahmet; Bini, Cesare; Biondi, Silvia; Bisanz, Tobias; Bjergaard, David Martin; Black, Curtis; Black, James; Black, Kevin; Blackburn, Daniel; Blair, Robert; Blazek, Tomas; Bloch, Ingo; Blocker, Craig; Blue, Andrew; Blum, Walter; Blumenschein, Ulrike; Blunier, Sylvain; Bobbink, Gerjan; Bobrovnikov, Victor; Bocchetta, Simona Serena; Bocci, Andrea; Bock, Christopher; Boehler, Michael; Boerner, Daniela; Bogaerts, Joannes Andreas; Bogavac, Danijela; Bogdanchikov, Alexander; Bohm, Christian; Boisvert, Veronique; Bokan, Petar; Bold, Tomasz; Boldyrev, Alexey; Bomben, Marco; Bona, Marcella; Boonekamp, Maarten; Borisov, Anatoly; Borissov, Guennadi; Bortfeldt, Jonathan; Bortoletto, Daniela; Bortolotto, Valerio; Bos, Kors; Boscherini, Davide; Bosman, Martine; Bossio Sola, Jonathan David; Boudreau, Joseph; Bouffard, Julian; Bouhova-Thacker, Evelina Vassileva; Boumediene, Djamel Eddine; Bourdarios, Claire; Boutle, Sarah Kate; Boveia, Antonio; Boyd, James; Boyko, Igor; Bracinik, Juraj; Brandt, Andrew; Brandt, Gerhard; Brandt, Oleg; Bratzler, Uwe; Brau, Benjamin; Brau, James; Breaden Madden, William Dmitri; Brendlinger, Kurt; Brennan, Amelia Jean; Brenner, Lydia; Brenner, Richard; Bressler, Shikma; Bristow, Timothy Michael; Britton, Dave; Britzger, Daniel; Brochu, Frederic; Brock, Ian; Brock, Raymond; Brooijmans, Gustaaf; Brooks, Timothy; Brooks, William; Brosamer, Jacquelyn; Brost, Elizabeth; Broughton, James; Bruckman de Renstrom, Pawel; Bruncko, Dusan; Bruneliere, Renaud; Bruni, Alessia; Bruni, Graziano; Bruni, Lucrezia Stella; Brunt, Benjamin; Bruschi, Marco; Bruscino, Nello; Bryant, Patrick; Bryngemark, Lene; Buanes, Trygve; Buat, Quentin; Buchholz, Peter; Buckley, Andrew; Budagov, Ioulian; Buehrer, Felix; Bugge, Magnar Kopangen; Bulekov, Oleg; Bullock, Daniel; Burckhart, Helfried; Burdin, Sergey; Burgard, Carsten Daniel; Burger, Angela Maria; Burghgrave, Blake; Burka, Klaudia; Burke, Stephen; Burmeister, Ingo; Burr, Jonathan Thomas Peter; Busato, Emmanuel; Büscher, Daniel; Büscher, Volker; Bussey, Peter; Butler, John; Buttar, Craig; Butterworth, Jonathan; Butti, Pierfrancesco; Buttinger, William; Buzatu, Adrian; Buzykaev, Aleksey; Cabrera Urbán, Susana; Caforio, Davide; Cairo, Valentina; Cakir, Orhan; Calace, Noemi; Calafiura, Paolo; Calandri, Alessandro; Calderini, Giovanni; Calfayan, Philippe; Callea, Giuseppe; Caloba, Luiz; Calvente Lopez, Sergio; Calvet, David; Calvet, Samuel; Calvet, Thomas Philippe; Camacho Toro, Reina; Camarda, Stefano; Camarri, Paolo; Cameron, David; Caminal Armadans, Roger; Camincher, Clement; Campana, Simone; Campanelli, Mario; Camplani, Alessandra; Campoverde, Angel; Canale, Vincenzo; Canepa, Anadi; Cano Bret, Marc; Cantero, Josu; Cao, Tingting; Capeans Garrido, Maria Del Mar; Caprini, Irinel; Caprini, Mihai; Capua, Marcella; Carbone, Ryne Michael; Cardarelli, Roberto; Cardillo, Fabio; Carli, Ina; Carli, Tancredi; Carlino, Gianpaolo; Carlson, Benjamin Taylor; Carminati, Leonardo; Carney, Rebecca; Caron, Sascha; Carquin, Edson; Carrillo-Montoya, German D; Carter, Janet; Carvalho, João; Casadei, Diego; Casado, Maria Pilar; Casolino, Mirkoantonio; Casper, David William; Castaneda-Miranda, Elizabeth; Castelijn, Remco; Castelli, Angelantonio; Castillo Gimenez, Victoria; Castro, Nuno Filipe; Catinaccio, Andrea; Catmore, James; Cattai, Ariella; Caudron, Julien; Cavaliere, Viviana; Cavallaro, Emanuele; Cavalli, Donatella; Cavalli-Sforza, Matteo; Cavasinni, Vincenzo; Ceradini, Filippo; Cerda Alberich, Leonor; Santiago Cerqueira, Augusto; Cerri, Alessandro; Cerrito, Lucio; Cerutti, Fabio; Cervelli, Alberto; Cetin, Serkant Ali; Chafaq, Aziz; Chakraborty, Dhiman; Chan, Stephen Kam-wah; Chan, Yat Long; Chang, Philip; Chapman, John Derek; Charlton, Dave; Chatterjee, Avishek; Chau, Chav Chhiv; Chavez Barajas, Carlos Alberto; Che, Siinn; Cheatham, Susan; Chegwidden, Andrew; Chekanov, Sergei; Chekulaev, Sergey; Chelkov, Gueorgui; Chelstowska, Magda Anna; Chen, Chunhui; Chen, Hucheng; Chen, Karen; Chen, Shenjian; Chen, Shion; Chen, Xin; Chen, Ye; Cheng, Hok Chuen; Cheng, Huajie; Cheng, Yangyang; Cheplakov, Alexander; Cheremushkina, Evgenia; Cherkaoui El Moursli, Rajaa; Chernyatin, Valeriy; Cheu, Elliott; Chevalier, Laurent; Chiarella, Vitaliano; Chiarelli, Giorgio; Chiodini, Gabriele; Chisholm, Andrew; Chitan, Adrian; Chizhov, Mihail; Choi, Kyungeon; Chomont, Arthur Rene; Chouridou, Sofia; Chow, Bonnie Kar Bo; Christodoulou, Valentinos; Chromek-Burckhart, Doris; Chudoba, Jiri; Chuinard, Annabelle Julia; Chwastowski, Janusz; Chytka, Ladislav; Ciapetti, Guido; Ciftci, Abbas Kenan; Cinca, Diane; Cindro, Vladimir; Cioara, Irina Antonela; Ciocca, Claudia; Ciocio, Alessandra; Cirotto, Francesco; Citron, Zvi Hirsh; Citterio, Mauro; Ciubancan, Mihai; Clark, Allan G; Clark, Brian Lee; Clark, Michael; Clark, Philip James; Clarke, Robert; Clement, Christophe; Coadou, Yann; Cobal, Marina; Coccaro, Andrea; Cochran, James H; Colasurdo, Luca; Cole, Brian; Colijn, Auke-Pieter; Collot, Johann; Colombo, Tommaso; Compostella, Gabriele; Conde Muiño, Patricia; Coniavitis, Elias; Connell, Simon Henry; Connelly, Ian; Consorti, Valerio; Constantinescu, Serban; Conti, Geraldine; Conventi, Francesco; Cooke, Mark; Cooper, Ben; Cooper-Sarkar, Amanda; Cormier, Felix; Cormier, Kyle James Read; Cornelissen, Thijs; Corradi, Massimo; Corriveau, Francois; Cortes-Gonzalez, Arely; Cortiana, Giorgio; Costa, Giuseppe; Costa, María José; Costanzo, Davide; Cottin, Giovanna; Cowan, Glen; Cox, Brian; Cranmer, Kyle; Crawley, Samuel Joseph; Cree, Graham; Crépé-Renaudin, Sabine; Crescioli, Francesco; Cribbs, Wayne Allen; Crispin Ortuzar, Mireia; Cristinziani, Markus; Croft, Vince; Crosetti, Giovanni; Cueto, Ana; Cuhadar Donszelmann, Tulay; Cummings, Jane; Curatolo, Maria; Cúth, Jakub; Czirr, Hendrik; Czodrowski, Patrick; D'amen, Gabriele; D'Auria, Saverio; D'Onofrio, Monica; Da Cunha Sargedas De Sousa, Mario Jose; Da Via, Cinzia; Dabrowski, Wladyslaw; Dado, Tomas; Dai, Tiesheng; Dale, Orjan; Dallaire, Frederick; Dallapiccola, Carlo; Dam, Mogens; Dandoy, Jeffrey; Dang, Nguyen Phuong; Daniells, Andrew Christopher; Dann, Nicholas Stuart; Danninger, Matthias; Dano Hoffmann, Maria; Dao, Valerio; Darbo, Giovanni; Darmora, Smita; Dassoulas, James; Dattagupta, Aparajita; Davey, Will; David, Claire; Davidek, Tomas; Davies, Merlin; Davison, Peter; Dawe, Edmund; Dawson, Ian; De, Kaushik; de Asmundis, Riccardo; De Benedetti, Abraham; De Castro, Stefano; De Cecco, Sandro; De Groot, Nicolo; de Jong, Paul; De la Torre, Hector; De Lorenzi, Francesco; De Maria, Antonio; De Pedis, Daniele; De Salvo, Alessandro; De Sanctis, Umberto; De Santo, Antonella; De Vivie De Regie, Jean-Baptiste; Dearnaley, William James; Debbe, Ramiro; Debenedetti, Chiara; Dedovich, Dmitri; Dehghanian, Nooshin; Deigaard, Ingrid; Del Gaudio, Michela; Del Peso, Jose; Del Prete, Tarcisio; Delgove, David; Deliot, Frederic; Delitzsch, Chris Malena; Dell'Acqua, Andrea; Dell'Asta, Lidia; Dell'Orso, Mauro; Della Pietra, Massimo; della Volpe, Domenico; Delmastro, Marco; Delsart, Pierre-Antoine; DeMarco, David; Demers, Sarah; Demichev, Mikhail; Demilly, Aurelien; Denisov, Sergey; Denysiuk, Denys; Derendarz, Dominik; Derkaoui, Jamal Eddine; Derue, Frederic; Dervan, Paul; Desch, Klaus Kurt; Deterre, Cecile; Dette, Karola; Deviveiros, Pier-Olivier; Dewhurst, Alastair; Dhaliwal, Saminder; Di Ciaccio, Anna; Di Ciaccio, Lucia; Di Clemente, William Kennedy; Di Donato, Camilla; Di Girolamo, Alessandro; Di Girolamo, Beniamino; Di Micco, Biagio; Di Nardo, Roberto; Di Simone, Andrea; Di Sipio, Riccardo; Di Valentino, David; Diaconu, Cristinel; Diamond, Miriam; Dias, Flavia; Diaz, Marco Aurelio; Diehl, Edward; Dietrich, Janet; Díez Cornell, Sergio; Dimitrievska, Aleksandra; Dingfelder, Jochen; Dita, Petre; Dita, Sanda; Dittus, Fridolin; Djama, Fares; Djobava, Tamar; Djuvsland, Julia Isabell; Barros do Vale, Maria Aline; Dobos, Daniel; Dobre, Monica; Doglioni, Caterina; Dolejsi, Jiri; Dolezal, Zdenek; Donadelli, Marisilvia; Donati, Simone; Dondero, Paolo; Donini, Julien; Dopke, Jens; Doria, Alessandra; Dova, Maria-Teresa; Doyle, Tony; Drechsler, Eric; Dris, Manolis; Du, Yanyan; Duarte-Campderros, Jorge; Duchovni, Ehud; Duckeck, Guenter; Ducu, Otilia Anamaria; Duda, Dominik; Dudarev, Alexey; Dudder, Andreas Christian; Duffield, Emily Marie; Duflot, Laurent; Dührssen, Michael; Dumancic, Mirta; Duncan, Anna Kathryn; Dunford, Monica; Duran Yildiz, Hatice; Düren, Michael; Durglishvili, Archil; Duschinger, Dirk; Dutta, Baishali; Dyndal, Mateusz; Eckardt, Christoph; Ecker, Katharina Maria; Edgar, Ryan Christopher; Edwards, Nicholas Charles; Eifert, Till; Eigen, Gerald; Einsweiler, Kevin; Ekelof, Tord; El Kacimi, Mohamed; Ellajosyula, Venugopal; Ellert, Mattias; Elles, Sabine; Ellinghaus, Frank; Elliot, Alison; Ellis, Nicolas; Elmsheuser, Johannes; Elsing, Markus; Emeliyanov, Dmitry; Enari, Yuji; Endner, Oliver Chris; Ennis, Joseph Stanford; Erdmann, Johannes; Ereditato, Antonio; Ernis, Gunar; Ernst, Jesse; Ernst, Michael; Errede, Steven; Ertel, Eugen; Escalier, Marc; Esch, Hendrik; Escobar, Carlos; Esposito, Bellisario; Etienvre, Anne-Isabelle; Etzion, Erez; Evans, Hal; Ezhilov, Alexey; Ezzi, Mohammed; Fabbri, Federica; Fabbri, Laura; Facini, Gabriel; Fakhrutdinov, Rinat; Falciano, Speranza; Falla, Rebecca Jane; Faltova, Jana; Fang, Yaquan; Fanti, Marcello; Farbin, Amir; Farilla, Addolorata; Farina, Christian; Farina, Edoardo Maria; Farooque, Trisha; Farrell, Steven; Farrington, Sinead; Farthouat, Philippe; Fassi, Farida; Fassnacht, Patrick; Fassouliotis, Dimitrios; Faucci Giannelli, Michele; Favareto, Andrea; Fawcett, William James; Fayard, Louis; Fedin, Oleg; Fedorko, Wojciech; Feigl, Simon; Feligioni, Lorenzo; Feng, Cunfeng; Feng, Eric; Feng, Haolu; Fenyuk, Alexander; Feremenga, Last; Fernandez Martinez, Patricia; Fernandez Perez, Sonia; Ferrando, James; Ferrari, Arnaud; Ferrari, Pamela; Ferrari, Roberto; Ferreira de Lima, Danilo Enoque; Ferrer, Antonio; Ferrere, Didier; Ferretti, Claudio; Fiedler, Frank; Filipčič, Andrej; Filipuzzi, Marco; Filthaut, Frank; Fincke-Keeler, Margret; Finelli, Kevin Daniel; Fiolhais, Miguel; Fiorini, Luca; Fischer, Adam; Fischer, Cora; Fischer, Julia; Fisher, Wade Cameron; Flaschel, Nils; Fleck, Ivor; Fleischmann, Philipp; Fletcher, Gareth Thomas; Fletcher, Rob Roy MacGregor; Flick, Tobias; Flierl, Bernhard Matthias; Flores Castillo, Luis; Flowerdew, Michael; Forcolin, Giulio Tiziano; Formica, Andrea; Forti, Alessandra; Foster, Andrew Geoffrey; Fournier, Daniel; Fox, Harald; Fracchia, Silvia; Francavilla, Paolo; Franchini, Matteo; Francis, David; Franconi, Laura; Franklin, Melissa; Frate, Meghan; Fraternali, Marco; Freeborn, David; Fressard-Batraneanu, Silvia; Friedrich, Felix; Froidevaux, Daniel; Frost, James; Fukunaga, Chikara; Fullana Torregrosa, Esteban; Fusayasu, Takahiro; Fuster, Juan; Gabaldon, Carolina; Gabizon, Ofir; Gabrielli, Alessandro; Gabrielli, Andrea; Gach, Grzegorz; Gadatsch, Stefan; Gagliardi, Guido; Gagnon, Louis Guillaume; Gagnon, Pauline; Galea, Cristina; Galhardo, Bruno; Gallas, Elizabeth; Gallop, Bruce; Gallus, Petr; Galster, Gorm Aske Gram Krohn; Gan, KK; Ganguly, Sanmay; Gao, Jun; Gao, Yanyan; Gao, Yongsheng; Garay Walls, Francisca; García, Carmen; García Navarro, José Enrique; Garcia-Sciveres, Maurice; Gardner, Robert; Garelli, Nicoletta; Garonne, Vincent; Gascon Bravo, Alberto; Gasnikova, Ksenia; Gatti, Claudio; Gaudiello, Andrea; Gaudio, Gabriella; Gauthier, Lea; Gavrilenko, Igor; Gay, Colin; Gaycken, Goetz; Gazis, Evangelos; Gecse, Zoltan; Gee, Norman; Geich-Gimbel, Christoph; Geisen, Marc; Geisler, Manuel Patrice; Gellerstedt, Karl; Gemme, Claudia; Genest, Marie-Hélène; Geng, Cong; Gentile, Simonetta; Gentsos, Christos; George, Simon; Gerbaudo, Davide; Gershon, Avi; Ghasemi, Sara; Ghneimat, Mazuza; Giacobbe, Benedetto; Giagu, Stefano; Giannetti, Paola; Gibson, Stephen; Gignac, Matthew; Gilchriese, Murdock; Gillam, Thomas; Gillberg, Dag; Gilles, Geoffrey; Gingrich, Douglas; Giokaris, Nikos; Giordani, MarioPaolo; Giorgi, Filippo Maria; Giraud, Pierre-Francois; Giromini, Paolo; Giugni, Danilo; Giuli, Francesco; Giuliani, Claudia; Giulini, Maddalena; Gjelsten, Børge Kile; Gkaitatzis, Stamatios; Gkialas, Ioannis; Gkougkousis, Evangelos Leonidas; Gladilin, Leonid; Glasman, Claudia; Glatzer, Julian; Glaysher, Paul; Glazov, Alexandre; Goblirsch-Kolb, Maximilian; Godlewski, Jan; Goldfarb, Steven; Golling, Tobias; Golubkov, Dmitry; Gomes, Agostinho; Gonçalo, Ricardo; Goncalves Pinto Firmino Da Costa, Joao; Gonella, Giulia; Gonella, Laura; Gongadze, Alexi; González de la Hoz, Santiago; Gonzalez-Sevilla, Sergio; Goossens, Luc; Gorbounov, Petr Andreevich; Gordon, Howard; Gorelov, Igor; Gorini, Benedetto; Gorini, Edoardo; Gorišek, Andrej; Gornicki, Edward; Goshaw, Alfred; Gössling, Claus; Gostkin, Mikhail Ivanovitch; Goudet, Christophe Raymond; Goujdami, Driss; Goussiou, Anna; Govender, Nicolin; Gozani, Eitan; Graber, Lars; Grabowska-Bold, Iwona; Gradin, Per Olov Joakim; Grafström, Per; Gramling, Johanna; Gramstad, Eirik; Grancagnolo, Sergio; Gratchev, Vadim; Gravila, Paul Mircea; Gray, Heather; Graziani, Enrico; Greenwood, Zeno Dixon; Grefe, Christian; Gregersen, Kristian; Gregor, Ingrid-Maria; Grenier, Philippe; Grevtsov, Kirill; Griffiths, Justin; Grillo, Alexander; Grimm, Kathryn; Grinstein, Sebastian; Gris, Philippe Luc Yves; Grivaz, Jean-Francois; Groh, Sabrina; Gross, Eilam; Grosse-Knetter, Joern; Grossi, Giulio Cornelio; Grout, Zara Jane; Guan, Liang; Guan, Wen; Guenther, Jaroslav; Guescini, Francesco; Guest, Daniel; Gueta, Orel; Gui, Bin; Guido, Elisa; Guillemin, Thibault; Guindon, Stefan; Gul, Umar; Gumpert, Christian; Guo, Jun; Guo, Yicheng; Gupta, Ruchi; Gupta, Shaun; Gustavino, Giuliano; Gutierrez, Phillip; Gutierrez Ortiz, Nicolas Gilberto; Gutschow, Christian; Guyot, Claude; Gwenlan, Claire; Gwilliam, Carl; Haas, Andy; Haber, Carl; Hadavand, Haleh Khani; Haddad, Nacim; Hadef, Asma; Hageböck, Stephan; Hagihara, Mutsuto; Hajduk, Zbigniew; Hakobyan, Hrachya; Haleem, Mahsana; Haley, Joseph; Halladjian, Garabed; Hallewell, Gregory David; Hamacher, Klaus; Hamal, Petr; Hamano, Kenji; Hamilton, Andrew; Hamity, Guillermo Nicolas; Hamnett, Phillip George; Han, Liang; Hanagaki, Kazunori; Hanawa, Keita; Hance, Michael; Haney, Bijan; Hanke, Paul; Hanna, Remie; Hansen, Jørgen Beck; Hansen, Jorn Dines; Hansen, Maike Christina; Hansen, Peter Henrik; Hara, Kazuhiko; Hard, Andrew; Harenberg, Torsten; Hariri, Faten; Harkusha, Siarhei; Harrington, Robert; Harrison, Paul Fraser; Hartjes, Fred; Hartmann, Nikolai Marcel; Hasegawa, Makoto; Hasegawa, Yoji; Hasib, Ahmed; Hassani, Samira; Haug, Sigve; Hauser, Reiner; Hauswald, Lorenz; Havranek, Miroslav; Hawkes, Christopher; Hawkings, Richard John; Hayakawa, Daiki; Hayden, Daniel; Hays, Chris; Hays, Jonathan Michael; Hayward, Helen; Haywood, Stephen; Head, Simon; Heck, Tobias; Hedberg, Vincent; Heelan, Louise; Heim, Sarah; Heim, Timon; Heinemann, Beate; Heinrich, Jochen Jens; Heinrich, Lukas; Heinz, Christian; Hejbal, Jiri; Helary, Louis; Hellman, Sten; Helsens, Clement; Henderson, James; Henderson, Robert; Heng, Yang; Henkelmann, Steffen; Henriques Correia, Ana Maria; Henrot-Versille, Sophie; Herbert, Geoffrey Henry; Herde, Hannah; Herget, Verena; Hernández Jiménez, Yesenia; Herten, Gregor; Hertenberger, Ralf; Hervas, Luis; Hesketh, Gavin Grant; Hessey, Nigel; Hetherly, Jeffrey Wayne; Higón-Rodriguez, Emilio; Hill, Ewan; Hill, John; Hiller, Karl Heinz; Hillier, Stephen; Hinchliffe, Ian; Hines, Elizabeth; Hirose, Minoru; Hirschbuehl, Dominic; Hoad, Xanthe; Hobbs, John; Hod, Noam; Hodgkinson, Mark; Hodgson, Paul; Hoecker, Andreas; Hoeferkamp, Martin; Hoenig, Friedrich; Hohn, David; Holmes, Tova Ray; Homann, Michael; Honda, Takuya; Hong, Tae Min; Hooberman, Benjamin Henry; Hopkins, Walter; Horii, Yasuyuki; Horton, Arthur James; Hostachy, Jean-Yves; Hou, Suen; Hoummada, Abdeslam; Howarth, James; Hoya, Joaquin; Hrabovsky, Miroslav; Hristova, Ivana; Hrivnac, Julius; Hryn'ova, Tetiana; Hrynevich, Aliaksei; Hsu, Pai-hsien Jennifer; Hsu, Shih-Chieh; Hu, Qipeng; Hu, Shuyang; Huang, Yanping; Hubacek, Zdenek; Hubaut, Fabrice; Huegging, Fabian; Huffman, Todd Brian; Hughes, Emlyn; Hughes, Gareth; Huhtinen, Mika; Huo, Peng; Huseynov, Nazim; Huston, Joey; Huth, John; Iacobucci, Giuseppe; Iakovidis, Georgios; Ibragimov, Iskander; Iconomidou-Fayard, Lydia; Ideal, Emma; Idrissi, Zineb; Iengo, Paolo; Igonkina, Olga; Iizawa, Tomoya; Ikai, Takashi; Ikegami, Yoichi; Ikeno, Masahiro; Ilchenko, Yuriy; Iliadis, Dimitrios; Ilic, Nikolina; Introzzi, Gianluca; Ioannou, Pavlos; Iodice, Mauro; Iordanidou, Kalliopi; Ippolito, Valerio; Ishijima, Naoki; Ishino, Masaya; Ishitsuka, Masaki; Ishmukhametov, Renat; Issever, Cigdem; Istin, Serhat; Ito, Fumiaki; Iturbe Ponce, Julia Mariana; Iuppa, Roberto; Iwanski, Wieslaw; Iwasaki, Hiroyuki; Izen, Joseph; Izzo, Vincenzo; Jabbar, Samina; Jackson, Brett; Jackson, Paul; Jain, Vivek; Jakobi, Katharina Bianca; Jakobs, Karl; Jakobsen, Sune; Jakoubek, Tomas; Jamin, David Olivier; Jana, Dilip; Jansky, Roland; Janssen, Jens; Janus, Michel; Janus, Piotr Andrzej; Jarlskog, Göran; Javadov, Namig; Javůrek, Tomáš; Jeanneau, Fabien; Jeanty, Laura; Jejelava, Juansher; Jeng, Geng-yuan; Jennens, David; Jenni, Peter; Jeske, Carl; Jézéquel, Stéphane; Ji, Haoshuang; Jia, Jiangyong; Jiang, Hai; Jiang, Yi; Jiang, Zihao; Jiggins, Stephen; Jimenez Pena, Javier; Jin, Shan; Jinaru, Adam; Jinnouchi, Osamu; Jivan, Harshna; Johansson, Per; Johns, Kenneth; Johnson, William Joseph; Jon-And, Kerstin; Jones, Graham; Jones, Roger; Jones, Sarah; Jones, Tim; Jongmanns, Jan; Jorge, Pedro; Jovicevic, Jelena; Ju, Xiangyang; Juste Rozas, Aurelio; Köhler, Markus Konrad; Kaczmarska, Anna; Kado, Marumi; Kagan, Harris; Kagan, Michael; Kahn, Sebastien Jonathan; Kaji, Toshiaki; Kajomovitz, Enrique; Kalderon, Charles William; Kaluza, Adam; Kama, Sami; Kamenshchikov, Andrey; Kanaya, Naoko; Kaneti, Steven; Kanjir, Luka; Kantserov, Vadim; Kanzaki, Junichi; Kaplan, Benjamin; Kaplan, Laser Seymour; Kapliy, Anton; Kar, Deepak; Karakostas, Konstantinos; Karamaoun, Andrew; Karastathis, Nikolaos; Kareem, Mohammad Jawad; Karentzos, Efstathios; Karnevskiy, Mikhail; Karpov, Sergey; Karpova, Zoya; Karthik, Krishnaiyengar; Kartvelishvili, Vakhtang; Karyukhin, Andrey; Kasahara, Kota; Kashif, Lashkar; Kass, Richard; Kastanas, Alex; Kataoka, Yousuke; Kato, Chikuma; Katre, Akshay; Katzy, Judith; Kawade, Kentaro; Kawagoe, Kiyotomo; Kawamoto, Tatsuo; Kawamura, Gen; Kazanin, Vassili; Keeler, Richard; Kehoe, Robert; Keller, John; Kempster, Jacob Julian; Keoshkerian, Houry; Kepka, Oldrich; Kerševan, Borut Paul; Kersten, Susanne; Keyes, Robert; Khader, Mazin; Khalil-zada, Farkhad; Khanov, Alexander; Kharlamov, Alexey; Kharlamova, Tatyana; Khoo, Teng Jian; Khovanskiy, Valery; Khramov, Evgeniy; Khubua, Jemal; Kido, Shogo; Kilby, Callum; Kim, Hee Yeun; Kim, Shinhong; Kim, Young-Kee; Kimura, Naoki; Kind, Oliver Maria; King, Barry; King, Matthew; Kirk, Julie; Kiryunin, Andrey; Kishimoto, Tomoe; Kisielewska, Danuta; Kiss, Florian; Kiuchi, Kenji; Kivernyk, Oleh; Kladiva, Eduard; Klein, Matthew Henry; Klein, Max; Klein, Uta; Kleinknecht, Konrad; Klimek, Pawel; Klimentov, Alexei; Klingenberg, Reiner; Klioutchnikova, Tatiana; Kluge, Eike-Erik; Kluit, Peter; Kluth, Stefan; Knapik, Joanna; Kneringer, Emmerich; Knoops, Edith; Knue, Andrea; Kobayashi, Aine; Kobayashi, Dai; Kobayashi, Tomio; Kobel, Michael; Kocian, Martin; Kodys, Peter; Koffas, Thomas; Koffeman, Els; Köhler, Nicolas Maximilian; Koi, Tatsumi; Kolanoski, Hermann; Kolb, Mathis; Koletsou, Iro; Komar, Aston; Komori, Yuto; Kondo, Takahiko; Kondrashova, Nataliia; Köneke, Karsten; König, Adriaan; Kono, Takanori; Konoplich, Rostislav; Konstantinidis, Nikolaos; Kopeliansky, Revital; Koperny, Stefan; Köpke, Lutz; Kopp, Anna Katharina; Korcyl, Krzysztof; Kordas, Kostantinos; Korn, Andreas; Korol, Aleksandr; Korolkov, Ilya; Korolkova, Elena; Kortner, Oliver; Kortner, Sandra; Kosek, Tomas; Kostyukhin, Vadim; Kotwal, Ashutosh; Koulouris, Aimilianos; Kourkoumeli-Charalampidi, Athina; Kourkoumelis, Christine; Kouskoura, Vasiliki; Kowalewska, Anna Bozena; Kowalewski, Robert Victor; Kowalski, Tadeusz; Kozakai, Chihiro; Kozanecki, Witold; Kozhin, Anatoly; Kramarenko, Viktor; Kramberger, Gregor; Krasnopevtsev, Dimitriy; Krasny, Mieczyslaw Witold; Krasznahorkay, Attila; Kravchenko, Anton; Kretz, Moritz; Kretzschmar, Jan; Kreutzfeldt, Kristof; Krieger, Peter; Krizka, Karol; Kroeninger, Kevin; Kroha, Hubert; Kroll, Joe; Kroseberg, Juergen; Krstic, Jelena; Kruchonak, Uladzimir; Krüger, Hans; Krumnack, Nils; Kruse, Mark; Kruskal, Michael; Kubota, Takashi; Kucuk, Hilal; Kuday, Sinan; Kuechler, Jan Thomas; Kuehn, Susanne; Kugel, Andreas; Kuger, Fabian; Kuhl, Thorsten; Kukhtin, Victor; Kukla, Romain; Kulchitsky, Yuri; Kuleshov, Sergey; Kuna, Marine; Kunigo, Takuto; Kupco, Alexander; Kurashige, Hisaya; Kurchaninov, Leonid; Kurochkin, Yurii; Kurth, Matthew Glenn; Kus, Vlastimil; Kuwertz, Emma Sian; Kuze, Masahiro; Kvita, Jiri; Kwan, Tony; Kyriazopoulos, Dimitrios; La Rosa, Alessandro; La Rosa Navarro, Jose Luis; La Rotonda, Laura; Lacasta, Carlos; Lacava, Francesco; Lacey, James; Lacker, Heiko; Lacour, Didier; Lacuesta, Vicente Ramón; Ladygin, Evgueni; Lafaye, Remi; Laforge, Bertrand; Lagouri, Theodota; Lai, Stanley; Lammers, Sabine; Lampl, Walter; Lançon, Eric; Landgraf, Ulrich; Landon, Murrough; Lanfermann, Marie Christine; Lang, Valerie Susanne; Lange, J örn Christian; Lankford, Andrew; Lanni, Francesco; Lantzsch, Kerstin; Lanza, Agostino; Laplace, Sandrine; Lapoire, Cecile; Laporte, Jean-Francois; Lari, Tommaso; Lasagni Manghi, Federico; Lassnig, Mario; Laurelli, Paolo; Lavrijsen, Wim; Law, Alexander; Laycock, Paul; Lazovich, Tomo; Lazzaroni, Massimo; Le, Brian; Le Dortz, Olivier; Le Guirriec, Emmanuel; Le Quilleuc, Eloi; LeBlanc, Matthew Edgar; LeCompte, Thomas; Ledroit-Guillon, Fabienne Agnes Marie; Lee, Claire Alexandra; Lee, Shih-Chang; Lee, Lawrence; Lefebvre, Benoit; Lefebvre, Guillaume; Lefebvre, Michel; Legger, Federica; Leggett, Charles; Lehan, Allan; Lehmann Miotto, Giovanna; Lei, Xiaowen; Leight, William Axel; Leister, Andrew Gerard; Leite, Marco Aurelio Lisboa; Leitner, Rupert; Lellouch, Daniel; Lemmer, Boris; Leney, Katharine; Lenz, Tatjana; Lenzi, Bruno; Leone, Robert; Leone, Sandra; Leonidopoulos, Christos; Leontsinis, Stefanos; Lerner, Giuseppe; Leroy, Claude; Lesage, Arthur; Lester, Christopher; Levchenko, Mikhail; Levêque, Jessica; Levin, Daniel; Levinson, Lorne; Levy, Mark; Lewis, Dave; Leyton, Michael; Li, Bing; Li, Changqiao; Li, Haifeng; Li, Lei; Li, Liang; Li, Qi; Li, Shu; Li, Xingguo; Li, Yichen; Liang, Zhijun; Liberti, Barbara; Liblong, Aaron; Lichard, Peter; Lie, Ki; Liebal, Jessica; Liebig, Wolfgang; Limosani, Antonio; Lin, Simon; Lin, Tai-Hua; Lindquist, Brian Edward; Lionti, Anthony Eric; Lipeles, Elliot; Lipniacka, Anna; Lisovyi, Mykhailo; Liss, Tony; Lister, Alison; Litke, Alan; Liu, Bo; Liu, Dong; Liu, Hao; Liu, Hongbin; Liu, Jian; Liu, Jianbei; Liu, Kun; Liu, Lulu; Liu, Minghui; Liu, Yanlin; Liu, Yanwen; Livan, Michele; Lleres, Annick; Llorente Merino, Javier; Lloyd, Stephen; Lo Sterzo, Francesco; Lobodzinska, Ewelina Maria; Loch, Peter; Loebinger, Fred; Loew, Kevin Michael; Loginov, Andrey; Lohse, Thomas; Lohwasser, Kristin; Lokajicek, Milos; Long, Brian Alexander; Long, Jonathan David; Long, Robin Eamonn; Longo, Luigi; Looper, Kristina Anne; Lopez Lopez, Jorge Andres; Lopez Mateos, David; Lopez Paredes, Brais; Lopez Paz, Ivan; Lopez Solis, Alvaro; Lorenz, Jeanette; Lorenzo Martinez, Narei; Losada, Marta; Lösel, Philipp Jonathan; Lou, XinChou; Lounis, Abdenour; Love, Jeremy; Love, Peter; Lu, Haonan; Lu, Nan; Lubatti, Henry; Luci, Claudio; Lucotte, Arnaud; Luedtke, Christian; Luehring, Frederick; Lukas, Wolfgang; Luminari, Lamberto; Lundberg, Olof; Lund-Jensen, Bengt; Luzi, Pierre Marc; Lynn, David; Lysak, Roman; Lytken, Else; Lyubushkin, Vladimir; Ma, Hong; Ma, Lian Liang; Ma, Yanhui; Maccarrone, Giovanni; Macchiolo, Anna; Macdonald, Calum Michael; Maček, Boštjan; Machado Miguens, Joana; Madaffari, Daniele; Madar, Romain; Maddocks, Harvey Jonathan; Mader, Wolfgang; Madsen, Alexander; Maeda, Junpei; Maeland, Steffen; Maeno, Tadashi; Maevskiy, Artem; Magradze, Erekle; Mahlstedt, Joern; Maiani, Camilla; Maidantchik, Carmen; Maier, Andreas Alexander; Maier, Thomas; Maio, Amélia; Majewski, Stephanie; Makida, Yasuhiro; Makovec, Nikola; Malaescu, Bogdan; Malecki, Pawel; Maleev, Victor; Malek, Fairouz; Mallik, Usha; Malon, David; Malone, Caitlin; Malone, Claire; Maltezos, Stavros; Malyukov, Sergei; Mamuzic, Judita; Mancini, Giada; Mandelli, Luciano; Mandić, Igor; Maneira, José; Manhaes de Andrade Filho, Luciano; Manjarres Ramos, Joany; Mann, Alexander; Manousos, Athanasios; Mansoulie, Bruno; Mansour, Jason Dhia; Mantifel, Rodger; Mantoani, Matteo; Manzoni, Stefano; Mapelli, Livio; Marceca, Gino; March, Luis; Marchiori, Giovanni; Marcisovsky, Michal; Marjanovic, Marija; Marley, Daniel; Marroquim, Fernando; Marsden, Stephen Philip; Marshall, Zach; Marti-Garcia, Salvador; Martin, Brian Thomas; Martin, Tim; Martin, Victoria Jane; Martin dit Latour, Bertrand; Martinez, Mario; Martinez Outschoorn, Verena; Martin-Haugh, Stewart; Martoiu, Victor Sorin; Martyniuk, Alex; Marzin, Antoine; Masetti, Lucia; Mashimo, Tetsuro; Mashinistov, Ruslan; Masik, Jiri; Maslennikov, Alexey; Massa, Ignazio; Massa, Lorenzo; Mastrandrea, Paolo; Mastroberardino, Anna; Masubuchi, Tatsuya; Mättig, Peter; Mattmann, Johannes; Maurer, Julien; Maxfield, Stephen; Maximov, Dmitriy; Mazini, Rachid; Maznas, Ioannis; Mazza, Simone Michele; Mc Fadden, Neil Christopher; Mc Goldrick, Garrin; Mc Kee, Shawn Patrick; McCarn, Allison; McCarthy, Robert; McCarthy, Tom; McClymont, Laurie; McDonald, Emily; Mcfayden, Josh; Mchedlidze, Gvantsa; McMahon, Steve; McNamara, Peter Charles; McPherson, Robert; Medinnis, Michael; Meehan, Samuel; Mehlhase, Sascha; Mehta, Andrew; Meier, Karlheinz; Meineck, Christian; Meirose, Bernhard; Melini, Davide; Mellado Garcia, Bruce Rafael; Melo, Matej; Meloni, Federico; Menary, Stephen Burns; Meng, Lingxin; Meng, Xiangting; Mengarelli, Alberto; Menke, Sven; Meoni, Evelin; Mergelmeyer, Sebastian; Mermod, Philippe; Merola, Leonardo; Meroni, Chiara; Merritt, Frank; Messina, Andrea; Metcalfe, Jessica; Mete, Alaettin Serhan; Meyer, Carsten; Meyer, Christopher; Meyer, Jean-Pierre; Meyer, Jochen; Meyer Zu Theenhausen, Hanno; Miano, Fabrizio; Middleton, Robin; Miglioranzi, Silvia; Mijović, Liza; Mikenberg, Giora; Mikestikova, Marcela; Mikuž, Marko; Milesi, Marco; Milic, Adriana; Miller, David; Mills, Corrinne; Milov, Alexander; Milstead, David; Minaenko, Andrey; Minami, Yuto; Minashvili, Irakli; Mincer, Allen; Mindur, Bartosz; Mineev, Mikhail; Minegishi, Yuji; Ming, Yao; Mir, Lluisa-Maria; Mistry, Khilesh; Mitani, Takashi; Mitrevski, Jovan; Mitsou, Vasiliki A; Miucci, Antonio; Miyagawa, Paul; Mizukami, Atsushi; Mjörnmark, Jan-Ulf; Mlynarikova, Michaela; Moa, Torbjoern; Mochizuki, Kazuya; Mogg, Philipp; Mohapatra, Soumya; Molander, Simon; Moles-Valls, Regina; Monden, Ryutaro; Mondragon, Matthew Craig; Mönig, Klaus; Monk, James; Monnier, Emmanuel; Montalbano, Alyssa; Montejo Berlingen, Javier; Monticelli, Fernando; Monzani, Simone; Moore, Roger; Morange, Nicolas; Moreno, Deywis; Moreno Llácer, María; Morettini, Paolo; Morgenstern, Stefanie; Mori, Daniel; Mori, Tatsuya; Morii, Masahiro; Morinaga, Masahiro; Morisbak, Vanja; Moritz, Sebastian; Morley, Anthony Keith; Mornacchi, Giuseppe; Morris, John; Mortensen, Simon Stark; Morvaj, Ljiljana; Moschovakos, Paris; Mosidze, Maia; Moss, Harry James; Moss, Josh; Motohashi, Kazuki; Mount, Richard; Mountricha, Eleni; Moyse, Edward; Muanza, Steve; Mudd, Richard; Mueller, Felix; Mueller, James; Mueller, Ralph Soeren Peter; Mueller, Thibaut; Muenstermann, Daniel; Mullen, Paul; Mullier, Geoffrey; Munoz Sanchez, Francisca Javiela; Murillo Quijada, Javier Alberto; Murray, Bill; Musheghyan, Haykuhi; Muškinja, Miha; Myagkov, Alexey; Myska, Miroslav; Nachman, Benjamin Philip; Nackenhorst, Olaf; Nagai, Koichi; Nagai, Ryo; Nagano, Kunihiro; Nagasaka, Yasushi; Nagata, Kazuki; Nagel, Martin; Nagy, Elemer; Nairz, Armin Michael; Nakahama, Yu; Nakamura, Koji; Nakamura, Tomoaki; Nakano, Itsuo; Naranjo Garcia, Roger Felipe; Narayan, Rohin; Narrias Villar, Daniel Isaac; Naryshkin, Iouri; Naumann, Thomas; Navarro, Gabriela; Nayyar, Ruchika; Neal, Homer; Nechaeva, Polina; Neep, Thomas James; Negri, Andrea; Negrini, Matteo; Nektarijevic, Snezana; Nellist, Clara; Nelson, Andrew; Nemecek, Stanislav; Nemethy, Peter; Nepomuceno, Andre Asevedo; Nessi, Marzio; Neubauer, Mark; Neumann, Manuel; Neves, Ricardo; Nevski, Pavel; Newman, Paul; Nguyen, Duong Hai; Nguyen Manh, Tuan; Nickerson, Richard; Nicolaidou, Rosy; Nielsen, Jason; Nikiforov, Andriy; Nikolaenko, Vladimir; Nikolic-Audit, Irena; Nikolopoulos, Konstantinos; Nilsen, Jon Kerr; Nilsson, Paul; Ninomiya, Yoichi; Nisati, Aleandro; Nisius, Richard; Nobe, Takuya; Nomachi, Masaharu; Nomidis, Ioannis; Nooney, Tamsin; Norberg, Scarlet; Nordberg, Markus; Norjoharuddeen, Nurfikri; Novgorodova, Olga; Nowak, Sebastian; Nozaki, Mitsuaki; Nozka, Libor; Ntekas, Konstantinos; Nurse, Emily; Nuti, Francesco; O'grady, Fionnbarr; O'Neil, Dugan; O'Rourke, Abigail Alexandra; O'Shea, Val; Oakham, Gerald; Oberlack, Horst; Obermann, Theresa; Ocariz, Jose; Ochi, Atsuhiko; Ochoa, Ines; Ochoa-Ricoux, Juan Pedro; Oda, Susumu; Odaka, Shigeru; Ogren, Harold; Oh, Alexander; Oh, Seog; Ohm, Christian; Ohman, Henrik; Oide, Hideyuki; Okawa, Hideki; Okumura, Yasuyuki; Okuyama, Toyonobu; Olariu, Albert; Oleiro Seabra, Luis Filipe; Olivares Pino, Sebastian Andres; Oliveira Damazio, Denis; Olszewski, Andrzej; Olszowska, Jolanta; Onofre, António; Onogi, Kouta; Onyisi, Peter; Oreglia, Mark; Oren, Yona; Orestano, Domizia; Orlando, Nicola; Orr, Robert; Osculati, Bianca; Ospanov, Rustem; Otero y Garzon, Gustavo; Otono, Hidetoshi; Ouchrif, Mohamed; Ould-Saada, Farid; Ouraou, Ahmimed; Oussoren, Koen Pieter; Ouyang, Qun; Owen, Mark; Owen, Rhys Edward; Ozcan, Veysi Erkcan; Ozturk, Nurcan; Pachal, Katherine; Pacheco Pages, Andres; Pacheco Rodriguez, Laura; Padilla Aranda, Cristobal; Pagáčová, Martina; Pagan Griso, Simone; Paganini, Michela; Paige, Frank; Pais, Preema; Pajchel, Katarina; Palacino, Gabriel; Palazzo, Serena; Palestini, Sandro; Palka, Marek; Pallin, Dominique; Panagiotopoulou, Evgenia; Panagoulias, Ilias; Pandini, Carlo Enrico; Panduro Vazquez, William; Pani, Priscilla; Panitkin, Sergey; Pantea, Dan; Paolozzi, Lorenzo; Papadopoulou, Theodora; Papageorgiou, Konstantinos; Paramonov, Alexander; Paredes Hernandez, Daniela; Parker, Adam Jackson; Parker, Michael Andrew; Parker, Kerry Ann; Parodi, Fabrizio; Parsons, John; Parzefall, Ulrich; Pascuzzi, Vincent; Pasqualucci, Enrico; Passaggio, Stefano; Pastore, Francesca; Pásztor, Gabriella; Pataraia, Sophio; Pater, Joleen; Pauly, Thilo; Pearce, James; Pearson, Benjamin; Pedersen, Lars Egholm; Pedersen, Maiken; Pedraza Lopez, Sebastian; Pedro, Rute; Peleganchuk, Sergey; Penc, Ondrej; Peng, Cong; Peng, Haiping; Penwell, John; Peralva, Bernardo; Perego, Marta Maria; Perepelitsa, Dennis; Perez Codina, Estel; Perini, Laura; Pernegger, Heinz; Perrella, Sabrina; Peschke, Richard; Peshekhonov, Vladimir; Peters, Krisztian; Peters, Yvonne; Petersen, Brian; Petersen, Troels; Petit, Elisabeth; Petridis, Andreas; Petridou, Chariclia; Petroff, Pierre; Petrolo, Emilio; Petrov, Mariyan; Petrucci, Fabrizio; Pettersson, Nora Emilia; Peyaud, Alan; Pezoa, Raquel; Phillips, Peter William; Piacquadio, Giacinto; Pianori, Elisabetta; Picazio, Attilio; Piccaro, Elisa; Piccinini, Maurizio; Pickering, Mark Andrew; Piegaia, Ricardo; Pilcher, James; Pilkington, Andrew; Pin, Arnaud Willy J; Pinamonti, Michele; Pinfold, James; Pingel, Almut; Pires, Sylvestre; Pirumov, Hayk; Pitt, Michael; Plazak, Lukas; Pleier, Marc-Andre; Pleskot, Vojtech; Plotnikova, Elena; Pluth, Daniel; Poettgen, Ruth; Poggioli, Luc; Pohl, David-leon; Polesello, Giacomo; Poley, Anne-luise; Policicchio, Antonio; Polifka, Richard; Polini, Alessandro; Pollard, Christopher Samuel; Polychronakos, Venetios; Pommès, Kathy; Pontecorvo, Ludovico; Pope, Bernard; Popeneciu, Gabriel Alexandru; Poppleton, Alan; Pospisil, Stanislav; Potamianos, Karolos; Potrap, Igor; Potter, Christina; Potter, Christopher; Poulard, Gilbert; Poveda, Joaquin; Pozdnyakov, Valery; Pozo Astigarraga, Mikel Eukeni; Pralavorio, Pascal; Pranko, Aliaksandr; Prell, Soeren; Price, Darren; Price, Lawrence; Primavera, Margherita; Prince, Sebastien; Prokofiev, Kirill; Prokoshin, Fedor; Protopopescu, Serban; Proudfoot, James; Przybycien, Mariusz; Puddu, Daniele; Purohit, Milind; Puzo, Patrick; Qian, Jianming; Qin, Gang; Qin, Yang; Quadt, Arnulf; Quayle, William; Queitsch-Maitland, Michaela; Quilty, Donnchadha; Raddum, Silje; Radeka, Veljko; Radescu, Voica; Radhakrishnan, Sooraj Krishnan; Radloff, Peter; Rados, Pere; Ragusa, Francesco; Rahal, Ghita; Raine, John Andrew; Rajagopalan, Srinivasan; Rammensee, Michael; Rangel-Smith, Camila; Ratti, Maria Giulia; Rauch, Daniel; Rauscher, Felix; Rave, Stefan; Ravenscroft, Thomas; Ravinovich, Ilia; Raymond, Michel; Read, Alexander Lincoln; Readioff, Nathan Peter; Reale, Marilea; Rebuzzi, Daniela; Redelbach, Andreas; Redlinger, George; Reece, Ryan; Reed, Robert; Reeves, Kendall; Rehnisch, Laura; Reichert, Joseph; Reiss, Andreas; Rembser, Christoph; Ren, Huan; Rescigno, Marco; Resconi, Silvia; Rezanova, Olga; Reznicek, Pavel; Rezvani, Reyhaneh; Richter, Robert; Richter, Stefan; Richter-Was, Elzbieta; Ricken, Oliver; Ridel, Melissa; Rieck, Patrick; Riegel, Christian Johann; Rieger, Julia; Rifki, Othmane; Rijssenbeek, Michael; Rimoldi, Adele; Rimoldi, Marco; Rinaldi, Lorenzo; Ristić, Branislav; Ritsch, Elmar; Riu, Imma; Rizatdinova, Flera; Rizvi, Eram; Rizzi, Chiara; Robertson, Steven; Robichaud-Veronneau, Andree; Robinson, Dave; Robinson, James; Robson, Aidan; Roda, Chiara; Rodina, Yulia; Rodriguez Perez, Andrea; Rodriguez Rodriguez, Daniel; Roe, Shaun; Rogan, Christopher Sean; Røhne, Ole; Roloff, Jennifer; Romaniouk, Anatoli; Romano, Marino; Romano Saez, Silvestre Marino; Romero Adam, Elena; Rompotis, Nikolaos; Ronzani, Manfredi; Roos, Lydia; Ros, Eduardo; Rosati, Stefano; Rosbach, Kilian; Rose, Peyton; Rosien, Nils-Arne; Rossetti, Valerio; Rossi, Elvira; Rossi, Leonardo Paolo; Rosten, Jonatan; Rosten, Rachel; Rotaru, Marina; Roth, Itamar; Rothberg, Joseph; Rousseau, David; Rozanov, Alexandre; Rozen, Yoram; Ruan, Xifeng; Rubbo, Francesco; Rudolph, Matthew Scott; Rühr, Frederik; Ruiz-Martinez, Aranzazu; Rurikova, Zuzana; Rusakovich, Nikolai; Ruschke, Alexander; Russell, Heather; Rutherfoord, John; Ruthmann, Nils; Ryabov, Yury; Rybar, Martin; Rybkin, Grigori; Ryu, Soo; Ryzhov, Andrey; Rzehorz, Gerhard Ferdinand; Saavedra, Aldo; Sabato, Gabriele; Sacerdoti, Sabrina; Sadrozinski, Hartmut; Sadykov, Renat; Safai Tehrani, Francesco; Saha, Puja; Sahinsoy, Merve; Saimpert, Matthias; Saito, Tomoyuki; Sakamoto, Hiroshi; Sakurai, Yuki; Salamanna, Giuseppe; Salamon, Andrea; Salazar Loyola, Javier Esteban; Salek, David; Sales De Bruin, Pedro Henrique; Salihagic, Denis; Salnikov, Andrei; Salt, José; Salvatore, Daniela; Salvatore, Pasquale Fabrizio; Salvucci, Antonio; Salzburger, Andreas; Sammel, Dirk; Sampsonidis, Dimitrios; Sánchez, Javier; Sanchez Martinez, Victoria; Sanchez Pineda, Arturo; Sandaker, Heidi; Sandbach, Ruth Laura; Sandhoff, Marisa; Sandoval, Carlos; Sankey, Dave; Sannino, Mario; Sansoni, Andrea; Santoni, Claudio; Santonico, Rinaldo; Santos, Helena; Santoyo Castillo, Itzebelt; Sapp, Kevin; Sapronov, Andrey; Saraiva, João; Sarrazin, Bjorn; Sasaki, Osamu; Sato, Koji; Sauvan, Emmanuel; Savage, Graham; Savard, Pierre; Savic, Natascha; Sawyer, Craig; Sawyer, Lee; Saxon, James; Sbarra, Carla; Sbrizzi, Antonio; Scanlon, Tim; Scannicchio, Diana; Scarcella, Mark; Scarfone, Valerio; Schaarschmidt, Jana; Schacht, Peter; Schachtner, Balthasar Maria; Schaefer, Douglas; Schaefer, Leigh; Schaefer, Ralph; Schaeffer, Jan; Schaepe, Steffen; Schaetzel, Sebastian; Schäfer, Uli; Schaffer, Arthur; Schaile, Dorothee; Schamberger, R Dean; Scharf, Veit; Schegelsky, Valery; Scheirich, Daniel; Schernau, Michael; Schiavi, Carlo; Schier, Sheena; Schillo, Christian; Schioppa, Marco; Schlenker, Stefan; Schmidt-Sommerfeld, Korbinian Ralf; Schmieden, Kristof; Schmitt, Christian; Schmitt, Stefan; Schmitz, Simon; Schneider, Basil; Schnoor, Ulrike; Schoeffel, Laurent; Schoening, Andre; Schoenrock, Bradley Daniel; Schopf, Elisabeth; Schott, Matthias; Schouwenberg, Jeroen; Schovancova, Jaroslava; Schramm, Steven; Schreyer, Manuel; Schuh, Natascha; Schulte, Alexandra; Schultens, Martin Johannes; Schultz-Coulon, Hans-Christian; Schulz, Holger; Schumacher, Markus; Schumm, Bruce; Schune, Philippe; Schwartzman, Ariel; Schwarz, Thomas Andrew; Schweiger, Hansdieter; Schwemling, Philippe; Schwienhorst, Reinhard; Schwindling, Jerome; Schwindt, Thomas; Sciolla, Gabriella; Scuri, Fabrizio; Scutti, Federico; Searcy, Jacob; Seema, Pienpen; Seidel, Sally; Seiden, Abraham; Seifert, Frank; Seixas, José; Sekhniaidze, Givi; Sekhon, Karishma; Sekula, Stephen; Seliverstov, Dmitry; Semprini-Cesari, Nicola; Serfon, Cedric; Serin, Laurent; Serkin, Leonid; Sessa, Marco; Seuster, Rolf; Severini, Horst; Sfiligoj, Tina; Sforza, Federico; Sfyrla, Anna; Shabalina, Elizaveta; Shaikh, Nabila Wahab; Shan, Lianyou; Shang, Ruo-yu; Shank, James; Shapiro, Marjorie; Shatalov, Pavel; Shaw, Kate; Shaw, Savanna Marie; Shcherbakova, Anna; Shehu, Ciwake Yusufu; Sherwood, Peter; Shi, Liaoshan; Shimizu, Shima; Shimmin, Chase Owen; Shimojima, Makoto; Shirabe, Shohei; Shiyakova, Mariya; Shmeleva, Alevtina; Shoaleh Saadi, Diane; Shochet, Mel; Shojaii, Seyed Ruhollah; Shope, David Richard; Shrestha, Suyog; Shulga, Evgeny; Shupe, Michael; Sicho, Petr; Sickles, Anne Marie; Sidebo, Per Edvin; Sideras Haddad, Elias; Sidiropoulou, Ourania; Sidorov, Dmitri; Sidoti, Antonio; Siegert, Frank; Sijacki, Djordje; Silva, José; Silverstein, Samuel; Simak, Vladislav; Simic, Ljiljana; Simion, Stefan; Simioni, Eduard; Simmons, Brinick; Simon, Dorian; Simon, Manuel; Sinervo, Pekka; Sinev, Nikolai; Sioli, Maximiliano; Siragusa, Giovanni; Sivoklokov, Serguei; Sjölin, Jörgen; Skinner, Malcolm Bruce; Skottowe, Hugh Philip; Skubic, Patrick; Slater, Mark; Slavicek, Tomas; Slawinska, Magdalena; Sliwa, Krzysztof; Slovak, Radim; Smakhtin, Vladimir; Smart, Ben; Smestad, Lillian; Smiesko, Juraj; Smirnov, Sergei; Smirnov, Yury; Smirnova, Lidia; Smirnova, Oxana; Smith, Joshua Wyatt; Smith, Matthew; Smith, Russell; Smizanska, Maria; Smolek, Karel; Snesarev, Andrei; Snyder, Ian Michael; Snyder, Scott; Sobie, Randall; Socher, Felix; Soffer, Abner; Soh, Dart-yin; Sokhrannyi, Grygorii; Solans Sanchez, Carlos; Solar, Michael; Soldatov, Evgeny; Soldevila, Urmila; Solodkov, Alexander; Soloshenko, Alexei; Solovyanov, Oleg; Solovyev, Victor; Sommer, Philip; Son, Hyungsuk; Song, Hong Ye; Sood, Alexander; Sopczak, Andre; Sopko, Vit; Sorin, Veronica; Sosa, David; Sotiropoulou, Calliope Louisa; Soualah, Rachik; Soukharev, Andrey; South, David; Sowden, Benjamin; Spagnolo, Stefania; Spalla, Margherita; Spangenberg, Martin; Spanò, Francesco; Sperlich, Dennis; Spettel, Fabian; Spieker, Thomas Malte; Spighi, Roberto; Spigo, Giancarlo; Spiller, Laurence Anthony; Spousta, Martin; St Denis, Richard Dante; Stabile, Alberto; Stamen, Rainer; Stamm, Soren; Stanecka, Ewa; Stanek, Robert; Stanescu, Cristian; Stanescu-Bellu, Madalina; Stanitzki, Marcel Michael; Stapnes, Steinar; Starchenko, Evgeny; Stark, Giordon; Stark, Jan; Staroba, Pavel; Starovoitov, Pavel; Stärz, Steffen; Staszewski, Rafal; Steinberg, Peter; Stelzer, Bernd; Stelzer, Harald Joerg; Stelzer-Chilton, Oliver; Stenzel, Hasko; Stewart, Graeme; Stillings, Jan Andre; Stockton, Mark; Stoebe, Michael; Stoicea, Gabriel; Stolte, Philipp; Stonjek, Stefan; Stradling, Alden; Straessner, Arno; Stramaglia, Maria Elena; Strandberg, Jonas; Strandberg, Sara; Strandlie, Are; Strauss, Michael; Strizenec, Pavol; Ströhmer, Raimund; Strom, David; Stroynowski, Ryszard; Strubig, Antonia; Stucci, Stefania Antonia; Stugu, Bjarne; Styles, Nicholas Adam; Su, Dong; Su, Jun; Suchek, Stanislav; Sugaya, Yorihito; Suk, Michal; Sulin, Vladimir; Sultansoy, Saleh; Sumida, Toshi; Sun, Siyuan; Sun, Xiaohu; Sundermann, Jan Erik; Suruliz, Kerim; Suster, Carl; Sutton, Mark; Suzuki, Shota; Svatos, Michal; Swiatlowski, Maximilian; Swift, Stewart Patrick; Sykora, Ivan; Sykora, Tomas; Ta, Duc; Taccini, Cecilia; Tackmann, Kerstin; Taenzer, Joe; Taffard, Anyes; Tafirout, Reda; Taiblum, Nimrod; Takai, Helio; Takashima, Ryuichi; Takeshita, Tohru; Takubo, Yosuke; Talby, Mossadek; Talyshev, Alexey; Tan, Kong Guan; Tanaka, Junichi; Tanaka, Masahiro; Tanaka, Reisaburo; Tanaka, Shuji; Tanioka, Ryo; Tannenwald, Benjamin Bordy; Tapia Araya, Sebastian; Tapprogge, Stefan; Tarem, Shlomit; Tartarelli, Giuseppe Francesco; Tas, Petr; Tasevsky, Marek; Tashiro, Takuya; Tassi, Enrico; Tavares Delgado, Ademar; Tayalati, Yahya; Taylor, Aaron; Taylor, Geoffrey; Taylor, Pierre Thor Elliot; Taylor, Wendy; Teischinger, Florian Alfred; Teixeira-Dias, Pedro; Temming, Kim Katrin; Temple, Darren; Ten Kate, Herman; Teng, Ping-Kun; Teoh, Jia Jian; Tepel, Fabian-Phillipp; Terada, Susumu; Terashi, Koji; Terron, Juan; Terzo, Stefano; Testa, Marianna; Teuscher, Richard; Theveneaux-Pelzer, Timothée; Thomas, Juergen; Thomas-Wilsker, Joshuha; Thompson, Paul; Thompson, Stan; Thomsen, Lotte Ansgaard; Thomson, Evelyn; Tibbetts, Mark James; Ticse Torres, Royer Edson; Tikhomirov, Vladimir; Tikhonov, Yury; Timoshenko, Sergey; Tipton, Paul; Tisserant, Sylvain; Todome, Kazuki; Todorov, Theodore; Todorova-Nova, Sharka; Tojo, Junji; Tokár, Stanislav; Tokushuku, Katsuo; Tolley, Emma; Tomlinson, Lee; Tomoto, Makoto; Tompkins, Lauren; Toms, Konstantin; Tong, Baojia(Tony); Tornambe, Peter; Torrence, Eric; Torres, Heberth; Torró Pastor, Emma; Toth, Jozsef; Touchard, Francois; Tovey, Daniel; Trefzger, Thomas; Tricoli, Alessandro; Trigger, Isabel Marian; Trincaz-Duvoid, Sophie; Tripiana, Martin; Trischuk, William; Trocmé, Benjamin; Trofymov, Artur; Troncon, Clara; Trottier-McDonald, Michel; Trovatelli, Monica; Truong, Loan; Trzebinski, Maciej; Trzupek, Adam; Tseng, Jeffrey; Tsiareshka, Pavel; Tsipolitis, Georgios; Tsirintanis, Nikolaos; Tsiskaridze, Shota; Tsiskaridze, Vakhtang; Tskhadadze, Edisher; Tsui, Ka Ming; Tsukerman, Ilya; Tsulaia, Vakhtang; Tsuno, Soshi; Tsybychev, Dmitri; Tu, Yanjun; Tudorache, Alexandra; Tudorache, Valentina; Tulbure, Traian Tiberiu; Tuna, Alexander Naip; Tupputi, Salvatore; Turchikhin, Semen; Turgeman, Daniel; Turk Cakir, Ilkay; Turra, Ruggero; Tuts, Michael; Ucchielli, Giulia; Ueda, Ikuo; Ughetto, Michael; Ukegawa, Fumihiko; Unal, Guillaume; Undrus, Alexander; Unel, Gokhan; Ungaro, Francesca; Unno, Yoshinobu; Unverdorben, Christopher; Urban, Jozef; Urquijo, Phillip; Urrejola, Pedro; Usai, Giulio; Usui, Junya; Vacavant, Laurent; Vacek, Vaclav; Vachon, Brigitte; Valderanis, Chrysostomos; Valdes Santurio, Eduardo; Valencic, Nika; Valentinetti, Sara; Valero, Alberto; Valery, Loic; Valkar, Stefan; Valls Ferrer, Juan Antonio; Van Den Wollenberg, Wouter; Van Der Deijl, Pieter; van der Graaf, Harry; van Eldik, Niels; van Gemmeren, Peter; Van Nieuwkoop, Jacobus; van Vulpen, Ivo; van Woerden, Marius Cornelis; Vanadia, Marco; Vandelli, Wainer; Vanguri, Rami; Vaniachine, Alexandre; Vankov, Peter; Vardanyan, Gagik; Vari, Riccardo; Varnes, Erich; Varol, Tulin; Varouchas, Dimitris; Vartapetian, Armen; Varvell, Kevin; Vasquez, Jared Gregory; Vasquez, Gerardo; Vazeille, Francois; Vazquez Schroeder, Tamara; Veatch, Jason; Veeraraghavan, Venkatesh; Veloce, Laurelle Maria; Veloso, Filipe; Veneziano, Stefano; Ventura, Andrea; Venturi, Manuela; Venturi, Nicola; Venturini, Alessio; Vercesi, Valerio; Verducci, Monica; Verkerke, Wouter; Vermeulen, Jos; Vest, Anja; Vetterli, Michel; Viazlo, Oleksandr; Vichou, Irene; Vickey, Trevor; Vickey Boeriu, Oana Elena; Viehhauser, Georg; Viel, Simon; Vigani, Luigi; Villa, Mauro; Villaplana Perez, Miguel; Vilucchi, Elisabetta; Vincter, Manuella; Vinogradov, Vladimir; Vittori, Camilla; Vivarelli, Iacopo; Vlachos, Sotirios; Vlasak, Michal; Vogel, Marcelo; Vokac, Petr; Volpi, Guido; Volpi, Matteo; von der Schmitt, Hans; von Toerne, Eckhard; Vorobel, Vit; Vorobev, Konstantin; Vos, Marcel; Voss, Rudiger; Vossebeld, Joost; Vranjes, Nenad; Vranjes Milosavljevic, Marija; Vrba, Vaclav; Vreeswijk, Marcel; Vuillermet, Raphael; Vukotic, Ilija; Wagner, Peter; Wagner, Wolfgang; Wahlberg, Hernan; Wahrmund, Sebastian; Wakabayashi, Jun; Walder, James; Walker, Rodney; Walkowiak, Wolfgang; Wallangen, Veronica; Wang, Chao; Wang, Chao; Wang, Fuquan; Wang, Haichen; Wang, Hulin; Wang, Jike; Wang, Jin; Wang, Kuhan; Wang, Rui; Wang, Song-Ming; Wang, Tingting; Wang, Wenxiao; Wanotayaroj, Chaowaroj; Warburton, Andreas; Ward, Patricia; Wardrope, David Robert; Washbrook, Andrew; Watkins, Peter; Watson, Alan; Watson, Miriam; Watts, Gordon; Watts, Stephen; Waugh, Ben; Webb, Samuel; Weber, Michele; Weber, Stefan Wolf; Weber, Stephen; Webster, Jordan S; Weidberg, Anthony; Weinert, Benjamin; Weingarten, Jens; Weiser, Christian; Weits, Hartger; Wells, Phillippa; Wenaus, Torre; Wengler, Thorsten; Wenig, Siegfried; Wermes, Norbert; Werner, Michael David; Werner, Per; Wessels, Martin; Wetter, Jeffrey; Whalen, Kathleen; Whallon, Nikola Lazar; Wharton, Andrew Mark; White, Andrew; White, Martin; White, Ryan; Whiteson, Daniel; Wickens, Fred; Wiedenmann, Werner; Wielers, Monika; Wiglesworth, Craig; Wiik-Fuchs, Liv Antje Mari; Wildauer, Andreas; Wilk, Fabian; Wilkens, Henric George; Williams, Hugh; Williams, Sarah; Willis, Christopher; Willocq, Stephane; Wilson, John; Wingerter-Seez, Isabelle; Winklmeier, Frank; Winston, Oliver James; Winter, Benedict Tobias; Wittgen, Matthias; Wolf, Tim Michael Heinz; Wolff, Robert; Wolter, Marcin Wladyslaw; Wolters, Helmut; Worm, Steven D; Wosiek, Barbara; Wotschack, Jorg; Woudstra, Martin; Wozniak, Krzysztof; Wu, Mengqing; Wu, Miles; Wu, Sau Lan; Wu, Xin; Wu, Yusheng; Wyatt, Terry Richard; Wynne, Benjamin; Xella, Stefania; Xi, Zhaoxu; Xu, Da; Xu, Lailin; Yabsley, Bruce; Yacoob, Sahal; Yamaguchi, Daiki; Yamaguchi, Yohei; Yamamoto, Akira; Yamamoto, Shimpei; Yamanaka, Takashi; Yamauchi, Katsuya; Yamazaki, Yuji; Yan, Zhen; Yang, Haijun; Yang, Hongtao; Yang, Yi; Yang, Zongchang; Yao, Weiming; Yap, Yee Chinn; Yasu, Yoshiji; Yatsenko, Elena; Yau Wong, Kaven Henry; Ye, Jingbo; Ye, Shuwei; Yeletskikh, Ivan; Yildirim, Eda; Yorita, Kohei; Yoshida, Rikutaro; Yoshihara, Keisuke; Young, Charles; Young, Christopher John; Youssef, Saul; Yu, David Ren-Hwa; Yu, Jaehoon; Yu, Jiaming; Yu, Jie; Yuan, Li; Yuen, Stephanie P; Yusuff, Imran; Zabinski, Bartlomiej; Zacharis, George; Zaidan, Remi; Zaitsev, Alexander; Zakharchuk, Nataliia; Zalieckas, Justas; Zaman, Aungshuman; Zambito, Stefano; Zanello, Lucia; Zanzi, Daniele; Zeitnitz, Christian; Zeman, Martin; Zemla, Andrzej; Zeng, Jian Cong; Zeng, Qi; Zenin, Oleg; Ženiš, Tibor; Zerwas, Dirk; Zhang, Dongliang; Zhang, Fangzhou; Zhang, Guangyi; Zhang, Huijun; Zhang, Jinlong; Zhang, Lei; Zhang, Liqing; Zhang, Matt; Zhang, Rui; Zhang, Ruiqi; Zhang, Xueyao; Zhang, Zhiqing; Zhao, Xiandong; Zhao, Yongke; Zhao, Zhengguo; Zhemchugov, Alexey; Zhong, Jiahang; Zhou, Bing; Zhou, Chen; Zhou, Lei; Zhou, Li; Zhou, Mingliang; Zhou, Ning; Zhu, Cheng Guang; Zhu, Hongbo; Zhu, Junjie; Zhu, Yingchun; Zhuang, Xuai; Zhukov, Konstantin; Zibell, Andre; Zieminska, Daria; Zimine, Nikolai; Zimmermann, Christoph; Zimmermann, Stephanie; Zinonos, Zinonas; Zinser, Markus; Ziolkowski, Michael; Živković, Lidija; Zobernig, Georg; Zoccoli, Antonio; zur Nedden, Martin; Zwalinski, Lukasz

    2017-05-18

    During 2015 the ATLAS experiment recorded $3.8 \\mathrm{fb}^{-1}$ of proton--proton collision data at a centre-of-mass energy of $13 \\mathrm{TeV}$. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton--proton collision data.

  8. Overview of Experiments for Physics of Fast Reactors from the International Handbooks of Evaluated Criticality Safety Benchmark Experiments and Evaluated Reactor Physics Benchmark Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bess, J. D.; Briggs, J. B.; Gulliford, J.; Ivanova, T.; Rozhikhin, E. V.; Semenov, M. Yu.; Tsibulya, A. M.; Koscheev, V. N.

    2017-07-01

    Overview of Experiments to Study the Physics of Fast Reactors Represented in the International Directories of Critical and Reactor Experiments John D. Bess Idaho National Laboratory Jim Gulliford, Tatiana Ivanova Nuclear Energy Agency of the Organisation for Economic Cooperation and Development E.V.Rozhikhin, M.Yu.Sem?nov, A.M.Tsibulya Institute of Physics and Power Engineering The study the physics of fast reactors traditionally used the experiments presented in the manual labor of the Working Group on Evaluation of sections CSEWG (ENDF-202) issued by the Brookhaven National Laboratory in 1974. This handbook presents simplified homogeneous model experiments with relevant experimental data, as amended. The Nuclear Energy Agency of the Organization for Economic Cooperation and Development coordinates the activities of two international projects on the collection, evaluation and documentation of experimental data - the International Project on the assessment of critical experiments (1994) and the International Project on the assessment of reactor experiments (since 2005). The result of the activities of these projects are replenished every year, an international directory of critical (ICSBEP Handbook) and reactor (IRPhEP Handbook) experiments. The handbooks present detailed models of experiments with minimal amendments. Such models are of particular interest in terms of the settlements modern programs. The directories contain a large number of experiments which are suitable for the study of physics of fast reactors. Many of these experiments were performed at specialized critical stands, such as BFS (Russia), ZPR and ZPPR (USA), the ZEBRA (UK) and the experimental reactor JOYO (Japan), FFTF (USA). Other experiments, such as compact metal assembly, is also of interest in terms of the physics of fast reactors, they have been carried out on the universal critical stands in Russian institutes (VNIITF and VNIIEF) and the US (LANL, LLNL, and others.). Also worth mentioning

  9. 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...

  10. Receiver ASIC for timing, trigger and control distribution in LHC experiments

    International Nuclear Information System (INIS)

    Christiansen, J.; Marchioro, A.; Moreira, P.; Sancho, A.

    1996-01-01

    An ASIC receiver has been developed for the optical timing, trigger and control distribution system for LHC detectors. It is capable of recovering the LHC reference clock and the first-level trigger decisions and making them available to the front-end electronics properly deskewed in time. The timing receiver is also capable of recognizing individually addressed commands to provide some slow control capability. Its main functions include post-amplification of the signal received from a photodetector-preamplifier, automatic gain control, data/clock separation, demultiplexing of the trigger and data channels and programmable coarse/fine deskewing functions. The design has been mapped into a standard 1microm CMOS process with all the analogue and timing critical functions implemented in full custom. The jitter measured on the recovered clock is less than 100 ps for input optical powers down to -25 dBm. The time deskewing functions allow the commands and the first level trigger accept signal to be phase shifted up to a maximum of sixteen clock cycles in steps of 0.1 ns

  11. The design and simulated performance of a fast Level 1 track trigger for the ATLAS High Luminosity Upgrade

    CERN Document Server

    Martensson, Mikael; The ATLAS collaboration

    2017-01-01

    The ATLAS experiment at the High Luminosity LHC will face a fivefold increase in the number of interactions per bunch crossing relative to the ongoing Run 2. This will require a proportional improvement in rejection power at the earliest levels of the detector trigger system, while preserving good signal efficiency. One critical aspect of this improvement will be the implementation of precise track reconstruction, through which sharper trigger turn-on curves can be achieved, and b-tagging and tau-tagging techniques can in principle be implemented. The challenge of such a project comes in the development of a fast, custom electronic device integrated in the hardware based first trigger level of the experiment. This article will discuss the requirements, architecture and projected performance of the system in terms of tracking, timing and physics, based on detailed simulations. Studies are carried out using data from the strip subsystem only or both strip and pixel subsystems.

  12. The design and simulated performance of a fast Level 1 track trigger for the ATLAS High Luminosity Upgrade

    CERN Document Server

    Martensson, Mikael; The ATLAS collaboration

    2017-01-01

    The ATLAS experiment at the high-luminosity LHC will face a five-fold increase in the number of interactions per collision relative to the ongoing Run 2. This will require a proportional improvement in rejection power at the earliest levels of the detector trigger system, while preserving good signal efficiency. One critical aspect of this improvement will be the implementation of precise track reconstruction, through which sharper trigger turn-on curves can be achieved, and b-tagging and tau-tagging techniques can in principle be implemented. The challenge of such a project comes in the development of a fast, custom electronic device integrated in the hardware-based first trigger level of the experiment, with repercussions propagating as far as the detector read-out philosophy. This talk will discuss the requirements, architecture and projected performance of the system in terms of tracking, timing and physics, based on detailed simulations. Studies are carried out comparing two detector geometries and using...

  13. Studies of ATM for ATLAS high-level triggers

    CERN Document Server

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

    2001-01-01

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

  14. 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.

  15. 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...

  16. 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...

  17. Role of Laboratory Plasma Experiments in exploring the Physics of Solar Eruptions

    Science.gov (United States)

    Tripathi, S.

    2017-12-01

    Solar eruptive events are triggered over a broad range of spatio-temporal scales by a variety of fundamental processes (e.g., force-imbalance, magnetic-reconnection, electrical-current driven instabilities) associated with arched magnetoplasma structures in the solar atmosphere. Contemporary research on solar eruptive events is at the forefront of solar and heliospheric physics due to its relevance to space weather. Details on the formation of magnetized plasma structures on the Sun, storage of magnetic energy in such structures over a long period (several Alfven transit times), and their impulsive eruptions have been recorded in numerous observations and simulated in computer models. Inherent limitations of space observations and uncontrolled nature of solar eruptions pose significant challenges in testing theoretical models and developing the predictive capability for space-weather. The pace of scientific progress in this area can be significantly boosted by tapping the potential of appropriately scaled laboratory plasma experiments to compliment solar observations, theoretical models, and computer simulations. To give an example, recent results from a laboratory plasma experiment on arched magnetic flux ropes will be presented and future challenges will be discussed. (Work supported by National Science Foundation, USA under award number 1619551)

  18. Physical modeling of the boiling crisis: theory and experiment

    International Nuclear Information System (INIS)

    Nikolayev, Vadim; Beysens, Daniel; Chatain, Denis

    2008-01-01

    Full text of publication follows: In this presentation we describe a physical approach to the boiling crisis called also the critical heat flux (CHF) phenomenon. This approach is based on the hypothesis that the boiling crisis is triggered by spreading of individual vapor bubbles over the heater or equivalently by the growth of individual dry spots under the bubbles. The role of bubble coalescence is assumed to be secondary. The spreading is due to forces acting at the microscopic scale, in the neighborhood of the line of triple contact of liquid, vapor and heater where the local heat fluxes are the strongest. This picture is supposed to be independent on boiling conditions. It is confirmed by the pool boiling experiments carried out at extremely high pressures close to the gas-liquid critical point. Such unusual conditions are chosen to slow down the bubble growth sufficiently to be able to observe the dryout dynamics. In the above experiments it lasted during about a minute. To keep the usual bubble geometry, it is necessary to perform such experiments under reduced gravity. The numerical simulations are carried out for high pressures. They show two regimes of bubble growth. When the heat flux is smaller than a threshold value associated with the CHF, a vapor bubble grows and then leaves the heater by buoyancy. When the heat flux is larger than the CHF, the bubble spreads over the heater without leaving it in agreement with the experimental data. This occurs because the vapor recoil force causes both bubble spreading and strong adhesion to the heater. The CHF variation with system parameters predicted by simulations is briefly discussed. (authors) [fr

  19. The design of the ZEUS tracking trigger and studies of b quark fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Silvester, I M

    1989-01-01

    This thesis consists of two parts, describing two very different aspects of experimental elementary particle physics. The first part describes, in detail, the design and estimated performance of a hardware track finding trigger processor. This processor is being built as part of the trigger for the ZEUS experiment, one of the two experiments being built to take data at the HERA electron-proton collider, currently under construction at the DESY laboratories in Hamburg. By using information from the main tracking chamber, the CTD, to reject data from events taking place outside the interaction region, this processor should be able to reduce the event rate from a beam crossing rate of 10{sup 6} s{sup -1} to approximately 9500 s{sup -1}. Used in conjunction with a trigger processor processing calorimeter data it should be able to achieve the desired first level trigger rate of 1 kHz. The second part describes two measurements of the fragmentation variable z for b quarks, made using a b enriched sample of 381 jets taken from the 31000 hadronic events with a centre of mass energy of 35 GeV observed with the TASSO detector during 1986. These measurements, obtained from the mean charged multiplicity and the rapidity distribution, have largely independent systematic uncertainties. The values obtained for (z{sub b}) were combined to give a value of 0.87{+-}0.02{+-}0.04. (author).

  20. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-07-01

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

  2. Triggering and data acquisition general considerations

    International Nuclear Information System (INIS)

    Butler, Joel N.

    2003-01-01

    We provide a general introduction to trigger and data acquisition systems in High Energy Physics. We emphasize the new possibilities and new approaches that have been made possible by developments in computer technology and networking

  3. On the granular fingering instability: controlled triggering in laboratory experiments and numerical simulations

    Science.gov (United States)

    Vriend, Nathalie; Tsang, Jonny; Arran, Matthew; Jin, Binbin; Johnsen, Alexander

    2017-11-01

    When a mixture of small, smooth particles and larger, coarse particles is released on a rough inclined plane, the initial uniform front may break up in distinct fingers which elongate over time. This fingering instability is sensitive to the unique arrangement of individual particles and is driven by granular segregation (Pouliquen et al., 1997). Variability in initial conditions create significant limitations for consistent experimental and numerical validation of newly developed theoretical models (Baker et al., 2016) for finger formation. We present an experimental study using a novel tool that sets the initial fingering width of the instability. By changing this trigger width between experiments, we explore the response of the avalanche breakup to perturbations of different widths. Discrete particle simulations (using MercuryDPM, Thornton et al., 2012) are conducted under a similar setting, reproducing the variable finger width, allowing validation between experiments and numerical simulations. A good agreement between simulations and experiments is obtained, and ongoing theoretical work is briefly introduced. NMV acknowledges the Royal Society Dorothy Hodgkin Research Fellowship.

  4. The LHCb vertex locator and level-1 trigger

    CERN Document Server

    Dijkstra, H

    2000-01-01

    LHCb will study CP violation and other rare phenomena in B-decays with a forward detector at the LHC. One of the challenges is to design a fast and efficient trigger. The design of the silicon Vertex Locator (VELO) has been driven by the requirements of one of the most selective triggers of the experiment. The VELO trigger is designed to work at an input rate of 1 MHz. The requirements and implementation of the VELO and the associated trigger are summarised, followed by a description of an upgrade which improves the trigger performance significantly. (3 refs).

  5. First order error corrections in common introductory physics experiments

    Science.gov (United States)

    Beckey, Jacob; Baker, Andrew; Aravind, Vasudeva; Clarion Team

    As a part of introductory physics courses, students perform different standard lab experiments. Almost all of these experiments are prone to errors owing to factors like friction, misalignment of equipment, air drag, etc. Usually these types of errors are ignored by students and not much thought is paid to the source of these errors. However, paying attention to these factors that give rise to errors help students make better physics models and understand physical phenomena behind experiments in more detail. In this work, we explore common causes of errors in introductory physics experiment and suggest changes that will mitigate the errors, or suggest models that take the sources of these errors into consideration. This work helps students build better and refined physical models and understand physics concepts in greater detail. We thank Clarion University undergraduate student grant for financial support involving this project.

  6. Pyranometer offsets triggered by ambient meteorology: insights from laboratory and field experiments

    Science.gov (United States)

    Oswald, Sandro M.; Pietsch, Helga; Baumgartner, Dietmar J.; Weihs, Philipp; Rieder, Harald E.

    2017-03-01

    This study investigates the effects of ambient meteorology on the accuracy of radiation (R) measurements performed with pyranometers contained in various heating and ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spray tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analyses of laboratory experiments showed that precipitation triggers zero offsets of -4 W m-2 or more, independent of the HV-system. Similar offsets were observed in field experiments under ambient environmental conditions, indicating a clear exceedance of BSRN (Baseline Surface Radiation Network) targets following precipitation events. All pyranometers required substantial time to return to their initial signal states after the simulated precipitation events. Therefore, for BSRN-class measurements, the recommendation would be to flag the radiation measurements during a natural precipitation event and 90 min after it in nighttime conditions. Further daytime experiments show pyranometer offsets of 50 W m-2 or more in comparison to the reference system. As they show a substantially faster recovery, the recommendation would be to flag the radiation measurements within a natural precipitation event and 10 min after it in daytime conditions.

  7. The development for the particle physics experiments platform in university

    International Nuclear Information System (INIS)

    Liang Futian; Yao Yuan; Wang Zhaoqi; Liu Yuzhe; Sang Ziru; Chen Lian; Wen Fei; Jin Ge; Liu Hongbin

    2012-01-01

    Nuclear science and particle physics is an important subject in physics, and it is important to launch particle physics experiments in university to training students. We design an experiments platform based on particle physics experiments in university. By employing digitalization and reconfiguration techniques in our design, we achieve all kinds of device functions with only one device. With the customized software for particular experiments and a website for teaching assistance, the platform is easy to be employed in universities. Students can accomplish a classical particle physics experiment in a modern way with the help of the platform, and they can also try new ideals. The experiments platform is ready to be used, and some of the lab sessions in USTC have already begin to use our experiments platform. (authors)

  8. Current Experiments in Particle Physics (September 1996)

    Energy Technology Data Exchange (ETDEWEB)

    Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.

    1996-09-01

    This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.

  9. Flavour Physics with High-Luminosity Experiments

    CERN Document Server

    2016-01-01

    With the first dedicated B-factory experiments BaBar (USA) and BELLE (Japan) Flavour Physics has entered the phase of precision physics. LHCb (CERN) and the high luminosity extension of KEK-B together with the state of the art BELLE II detector will further push this precision frontier. Progress in this field always relied on close cooperation between experiment and theory, as extraction of fundamental parameters often is very indirect. To extract the full physics information from existing and future data, this cooperation must be further intensified. This MIAPP programme aims in particular to prepare for this task by joining experimentalists and theorists in the various relevant fields, with the goal to build the necessary tools in face of the challenge of new large data sets. The programme will begin with a focus on physics with non-leptonic final states, continued by semileptonic B meson decays and Tau decays, and on various aspects of CP symmetry violation closer to the end. In addition, in the final ...

  10. 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.

  11. Fast simulation of the trigger system of the ATLAS detector at LHC

    International Nuclear Information System (INIS)

    Epp, B.; Ghete, V.M.; Kuhn, D.; Zhang, Y.J.

    2004-01-01

    The trigger system of the ATLAS detector aims to maximize the physics coverage and to be open to new and possibly unforeseen physics signatures. It is a multi-level system, composed from a hardware trigger at level-1, followed by the high-level-trigger (level-2 and event-filter). In order to understand its performance, to optimize it and to reduce its total cost, the trigger system requires a detailed simulation which is time- and resource-consuming. An alternative to the full detector simulation is a so-called 'fast simulation' which starts the analysis from particle level and replaces the full detector simulation and the detailed particle tracking with parametrized distributions obtained from the full simulation and/or a simplified detector geometry. The fast simulation offers a less precise description of trigger performance, but it is faster and less resource-consuming. (author)

  12. Unfolding methods in high-energy physics experiments

    International Nuclear Information System (INIS)

    Blobel, V.

    1985-01-01

    Distributions measured in high-energy physics experiments are often distorted or transformed by limited acceptance and finite resolution of the detectors. The unfolding of measured distributions is an important, but due to inherent instabilities a very difficult problem. Methods for unfolding, applicable for the analysis of high-energy physics experiments, and their properties are discussed. An introduction is given to the method of regularization. (orig.)

  13. Unfolding methods in high-energy physics experiments

    International Nuclear Information System (INIS)

    Blobel, V.

    1984-12-01

    Distributions measured in high-energy physics experiments are often distorted or transformed by limited acceptance and finite resolution of the detectors. The unfolding of measured distributions is an important, but due to inherent instabilities a very difficult problem. Methods for unfolding, applicable for the analysis of high-energy physics experiments, and their properties are discussed. An introduction is given to the method of regularization. (orig.)

  14. Hadronic triggers and trigger object-level analysis at ATLAS

    CERN Document Server

    Zaripovas, Donatas Ramilas; The ATLAS collaboration

    2017-01-01

    Hadronic signatures are critical to the high energy physics analysis program at the Large Hadron Collider (LHC), and are broadly used for both Standard Model measurements and searches for new physics. These signatures include generic quark and gluon jets, as well as jets originating from b-quarks or the decay of massive particles (such as electroweak bosons or top quarks). Additionally missing transverse momentum from non-interacting particles provides an interesting probe in the search for new physics beyond the Standard Model. Developing trigger selections that target these events is a huge challenge at the LHC due to the enormous event rates associated with these signatures. This challenge is exacerbated by the amount of pile-up activity, which continues to grow. In order to address these challenges, several new techniques have been developed during the past year in order to significantly improve the potential of the 2017 dataset and overcome the limiting factors, such as storage and computing requirements...

  15. Performance of a First-Level Muon Trigger with High Momentum Resolution Based on the ATLAS MDT Chambers for HL-LHC

    CERN Document Server

    Gadow, P.; Kortner, S.; Kroha, H.; Müller, F.; Richter, R.

    2016-01-01

    Highly selective first-level triggers are essential to exploit the full physics potential of the ATLAS experiment at High-Luminosity LHC (HL-LHC). The concept for a new muon trigger stage using the precision monitored drift tube (MDT) chambers to significantly improve the selectivity of the first-level muon trigger is presented. It is based on fast track reconstruction in all three layers of the existing MDT chambers, made possible by an extension of the first-level trigger latency to six microseconds and a new MDT read-out electronics required for the higher overall trigger rates at the HL-LHC. Data from $pp$-collisions at $\\sqrt{s} = 8\\,\\mathrm{TeV}$ is used to study the minimal muon transverse momentum resolution that can be obtained using the MDT precision chambers, and to estimate the resolution and efficiency of the MDT-based trigger. A resolution of better than $4.1\\%$ is found in all sectors under study. With this resolution, a first-level trigger with a threshold of $18\\,\\mathrm{GeV}$ becomes fully e...

  16. Efficient, reliable and fast high-level triggering using a bonsai boosted decision tree

    International Nuclear Information System (INIS)

    Gligorov, V V; Williams, M

    2013-01-01

    High-level triggering is a vital component of many modern particle physics experiments. This paper describes a modification to the standard boosted decision tree (BDT) classifier, the so-called bonsai BDT, that has the following important properties: it is more efficient than traditional cut-based approaches; it is robust against detector instabilities, and it is very fast. Thus, it is fit-for-purpose for the online running conditions faced by any large-scale data acquisition system.

  17. 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 ...

  18. 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...

  19. 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...

  20. AGS experiments in nuclear/QCD physics at medium energies

    Energy Technology Data Exchange (ETDEWEB)

    Lo Presti, P.

    1998-07-01

    This report contains a diagram of the experimental setup for each experiment as well as giving a brief discussion of its purpose and list of collaborators for the experiment. Thirty-one experiments in the areas of nuclear physics and particle physics are covered. It concludes with a list of publications of the AGS experiments.

  1. AGS experiments in nuclear/QCD physics at medium energies

    International Nuclear Information System (INIS)

    Lo Presti, P.

    1998-07-01

    This report contains a diagram of the experimental setup for each experiment as well as giving a brief discussion of its purpose and list of collaborators for the experiment. Thirty-one experiments in the areas of nuclear physics and particle physics are covered. It concludes with a list of publications of the AGS experiments

  2. Laboratory Experiments in Physics for Modern Astronomy With Comprehensive Development of the Physical Principles

    CERN Document Server

    Golden, Leslie

    2013-01-01

    This book presents experiments which will teach physics relevant to astronomy. The astronomer, as instructor, frequently faces this need when his college or university has no astronomy department and any astronomy course is taught in the physics department. The physicist, as instructor, will find this intellectually appealing when faced with teaching an introductory astronomy course. From these experiments, the student will acquire important analytical tools, learn physics appropriate to astronomy, and experience instrument calibration and the direct gathering and analysis of data. Experiments that can be performed in one laboratory session as well as semester-long observation projects are included. This textbook is aimed at undergraduate astronomy students.

  3. Current experiments in elementary particle physics. Revision 1-85

    International Nuclear Information System (INIS)

    Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.

    1985-01-01

    This report contains summaries of 551 approved experiments in elementary particle physics (experiments that finished taking data before 1 January 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Properties of the fixed-target beams at most of the laboratories are summarized. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries

  4. The PRad experiment and the proton radius puzzle

    Directory of Open Access Journals (Sweden)

    Gasparian Ashot

    2014-06-01

    Full Text Available New results from the recent muonic hydrogen experiments seriously questioned our knowledge of the proton charge radius, rp. The new value, with its unprecedented less than sub-percent precision, is currently up to eight standard deviation smaller than the average value from all previous experiments, triggering the well-known “proton charge radius puzzle” in nuclear and atomic physics. The PRad collaboration is currently preparing a novel, magnetic-spectrometer-free ep scattering experiment in Hall B at JLab for a new independent rp measurement to address this growing “puzzle” in physics.

  5. Sustained Spheromak Physics Experiment, SSPX

    International Nuclear Information System (INIS)

    Hooper, E.B.

    1997-01-01

    The Sustained Spheromak Physics Experiment is proposed for experimental studies of spheromak confinement issues in a controlled way: in steady state relative to the confinement timescale and at low collisionality. Experiments in a flux - conserver will provide data on transport in the presence of resistive modes in shear-stabilized systems and establish operating regimes which pave the way for true steady-state experiments with the equilibrium field supplied by external coils. The proposal is based on analysis of past experiments, including the achievement of T e = 400 eV in a decaying spheromak in CTX. Electrostatic helicity injection from a coaxial ''''gun'''' into a shaped flux conserver will form and sustain the plasma for several milliseconds. The flux conserver minimizes fluxline intersection with the walls and provides MHD stability. Improvements from previous experiments include modem wall conditioning (especially boronization), a divertor for density and impurity control, and a bias magnetic flux for configurational flexibility. The bias flux will provide innovative experimental opportunities, including testing helicity drive on the large-radius plasma boundary. Diagnostics include Thomson scattering for T e measurements and ultra-short pulse reflectrometry to measure density and magnetic field profiles and turbulence. We expect to operate at T e of several hundred eV, allowing improved understanding of energy and current transport due to resistive MHD turbulence during sustained operation. This will provide an exciting advance in spheromak physics and a firm basis for future experiments in the fusion regime

  6. The D0 run II trigger system

    International Nuclear Information System (INIS)

    Schwienhorst, Reinhard; Michigan State U.

    2004-01-01

    The D0 detector at the Fermilab Tevatron was upgraded for Run II. This upgrade included improvements to the trigger system in order to be able to handle the increased Tevatron luminosity and higher bunch crossing rates compared to Run I. The D0 Run II trigger is a highly exible system to select events to be written to tape from an initial interaction rate of about 2.5 MHz. This is done in a three-tier pipelined, buffered system. The first tier (level 1) processes fast detector pick-off signals in a hardware/firmware based system to reduce the event rate to about 1. 5kHz. The second tier (level 2) uses information from level 1 and forms simple Physics objects to reduce the rate to about 850 Hz. The third tier (level 3) uses full detector readout and event reconstruction on a filter farm to reduce the rate to 20-30 Hz. The D0 trigger menu contains a wide variety of triggers. While the emphasis is on triggering on generic lepton and jet final states, there are also trigger terms for specific final state signatures. In this document we describe the D0 trigger system as it was implemented and is currently operating in Run II

  7. 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.

  8. 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...

  9. 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 ...

  10. Challenges and Performance of the Frontier Technology Applied to an ATLAS Phase-I Calorimeter Trigger Board Dedicated to the Jet Identification

    CERN Document Server

    Kahra, Christian; The ATLAS collaboration

    2017-01-01

    The '{Phase-I}' upgrade of the Large Hadron Collider (LHC), scheduled to be completed in 2021, will lead to an enhanced collision luminosity of $2.5 \\times 10^{34} \\, \\mathrm{cm}^{-2} \\, \\mathrm{s}^{-1}$. To cope with the new and challenging accelerator conditions, all the CERN experiments have planned a major detector upgrade to be installed during the associated experimental shutdown period. One of the physics goals of the ATLAS experiment is to maintain sensitivity to electroweak processes despite the increased number of interactions per LHC bunch crossing. To this end, the component of the first level hardware trigger based on calorimeter data will be upgraded to exploit fine-granularity readout using a new system of Feature EXtractors (FEXs), which each uses different physics objects for trigger selection. There will be three FEX systems in total, with this contribution focusing on the first prototype of the jet FEX (jFEX). This system identifies jets and large area tau candidates while also calculating ...

  11. 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.

  12. Triggering on electrons and photons with CMS

    Directory of Open Access Journals (Sweden)

    Zabi Alexandre

    2012-06-01

    Full Text Available Throughout the year 2011, the Large Hadron Collider (LHC has operated with an instantaneous luminosity that has risen continually to around 4 × 1033cm−2s−1. With this prodigious high-energy proton collisions rate, efficient triggering on electrons and photons has become a major challenge for the LHC experiments. The Compact Muon Solenoid (CMS experiment implements a sophisticated two-level online selection system that achieves a rejection factor of nearly 106. The first level (L1 is based on coarse information coming from the calorimeters and the muon detectors while the High-Level Trigger (HLT combines fine-grain information from all sub-detectors. In this intense hadronic environment, the L1 electron/photon trigger provides a powerful tool to select interesting events. It is based upon information from the Electromagnetic Calorimeter (ECAL, a high-resolution detector comprising 75848 lead tungstate (PbWO4 crystals in a “barrel” and two “endcaps”. The performance as well as the optimization of the electron/photon trigger are presented.

  13. KATANA – A charge-sensitive triggering system for the SπRIT experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lasko, P. [Institute of Nuclear Physics, Polish Academy of Sciences,Kraków (Poland); Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University,Kraków (Poland); Adamczyk, M.; Brzychczyk, J. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University,Kraków (Poland); Hirnyk, P.; Łukasik, J. [Institute of Nuclear Physics, Polish Academy of Sciences,Kraków (Poland); Pawłowski, P., E-mail: piotr.pawlowski@ifj.edu.pl [Institute of Nuclear Physics, Polish Academy of Sciences,Kraków (Poland); Pelczar, K. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University,Kraków (Poland); Snoch, A. [University of Wroclaw, Wrocław (Poland); Sochocka, A.; Sosin, Z. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University,Kraków (Poland); Barney, J. [Department of Physics and Astronomy, Michigan State University, East Lansing (United States); National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing (United States); Cerizza, G. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing (United States); Estee, J. [Department of Physics and Astronomy, Michigan State University, East Lansing (United States); National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing (United States); Isobe, T. [RIKEN Nishina Center, Wako, Saitama (Japan); Jhang, G. [Department of Physics, Korea University, Seoul (Korea, Republic of); Kaneko, M. [Department of Physics, Kyoto University, Kita-shirakawa, Kyoto (Japan); Kurata-Nishimura, M. [RIKEN Nishina Center, Wako, Saitama (Japan); and others

    2017-06-01

    KATANA - the Krakow Array for Triggering with Amplitude discrimiNAtion - has been built and used as a trigger and veto detector for the SπRIT TPC at RIKEN. Its construction allows operating in magnetic field and providing fast response for ionizing particles, giving an approximate forward multiplicity and charge information. Depending on this information, trigger and veto signals are generated. The article presents performance of the detector and details of its construction. A simple phenomenological parametrization of the number of emitted scintillation photons in plastic scintillator is proposed. The effect of the light output deterioration in the plastic scintillator due to the in-beam irradiation is discussed.

  14. The Terabit/s Super-Fragment Builder and Trigger Throttling System for the Compact Muon Solenoid Experiment at CERN

    CERN Document Server

    Bauer, Gerry; Boyer, Vincent; Branson, James; Brett, Angela; Cano, Eric; Carboni, Andrea; Ciganek, Marek; Cittolin, Sergio; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gómez-Reino, Robert; Gulmini, Michele; Gutíerrez-Mlot, Esteban; Gutleber, Johannes; Jacobs, Claude; Kim, Jin Cheol; Klute, Markus; Lipeles, Elliot; Lopez-Perez, Juan Antonio; Maron, Gaetano; Meijers, Frans; Meschi, Emilio; Moser, Roland; Murray, Steven; Oh, Alexander; Orsini, Luciano; Paus, Christoph; Petrucci, Andrea; Pieri, Marco; Pollet, Lucien; Rácz, Attila; Sakulin, Hannes; Sani, Matteo; Schieferdecker, Philipp; Schwick, Christoph; Sumorok, Konstanty; Suzuki, Ichiro; Tsirigkas, Dimitrios

    2007-01-01

    The Data Acquisition System of the Compact Muon Solenoid experiment at the Large Hadron Collider reads out event fragments of an average size of 2 kilobytes from around 650 detector front-ends at a rate of up to 100 kHz. The first stage of event-building is performed by the Super-Fragment Builder employing custom-built electronics and a Myrinet optical network. It reduces the number of fragments by one order of magnitude, thereby greatly decreasing the requirements for the subsequent event-assembly stage. By providing fast feedback from any of the front-ends to the trigger, the Trigger Throttling System prevents buffer overflows in the front-end electronics due to variations in the size and rate of events or due to back-pressure from the down-stream event-building and processing. This paper reports on new performance measurements and on the recent successful integration of a scaled-down setup of the described system with the trigger and with front-ends of all major sub-detectors. The on-going commissioning of...

  15. 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.

  16. Beam-plasma coupling physics in support of active experiments

    Science.gov (United States)

    Yakymenko, K.; Delzanno, G. L.; Roytershteyn, V.

    2017-12-01

    The recent development of compact relativistic accelerators might open up a new era of active experiments in space, driven by important scientific and national security applications. Examples include using electron beams to trace magnetic field lines and establish causality between physical processes occurring in the magnetosphere and those in the ionosphere. Another example is the use of electron beams to trigger waves in the near-Earth environment. Waves could induce pitch-angle scattering and precipitation of energetic electrons, acting as an effective radiation belt remediation scheme. In this work, we revisit the coupling between an electron beam and a magnetized plasma in the framework of linear cold-plasma theory. We show that coupling can occur through two different regimes. In the first, a non-relativistic beam radiates through whistler waves. This is well known, and was in fact the focus of many rockets and space-shuttle campaigns aimed at demonstrating whistler emissions in the eighties. In the second regime, the beam radiates through extraordinary (R-X) modes. Nonlinear simulations with a highly-accurate Vlasov code support the theoretical results qualitatively and demonstrate that the radiated power through R-X modes can be much larger than in the whistler regime. Test-particle simulations in the wave electromagnetic field will also be presented to assess the efficiency of these waves in inducing pitch-angle scattering via wave-particle interactions. Finally, the implications of these results for a rocket active experiment in the ionosphere and for a radiation belt remediation scheme will be discussed.

  17. Current experiments in elementary-particle physics

    International Nuclear Information System (INIS)

    Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.

    1983-03-01

    Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (BNL); CERN; CESR; DESY; Fermilab (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMF. Also, summaries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated

  18. Department of High Energy Physics - Overview

    International Nuclear Information System (INIS)

    Bialkowska, H.

    2009-01-01

    Full text: The main activities of the Department can be grouped into four parts: I. An ongoing analysis of data from large accelerator facilities At CERN SPS: The Compass experiment, ' a flagship of the CERN fixed target program ', studies the structure of the nucleon. Gluon polarization analysis was the main subject this year. Compass is an active experiment, and there is an ongoing effort in data taking and detector development. Two heavy ion experiments, WA98 and NA49, have finished data taking, but continue analysis. In 2008, important results on transverse momentum spectra were published. At COSY: The WASA experiment works with low energy (up to 3.7 GeV) beams of protons and deuterons, studying rare decays of eta mesons. New limits on branching ratios for such decays have been determined. This information is important for the theory of C and CP symmetry, and chiral perturbation theory. II. Preparations for soon-to-be-operating experiments at the LHC Three teams work on LHC experiments: CMS, LHCb and ALICE. The CMS experiment is ready for data taking. The muon trigger system, based on resistive plate chambers RPC, has been installed and tested using cosmic ray muons. Simulations of physical processes predicted by some extensions of the Standard Model were performed. The LHCb experiment team has worked on the system of the Inner Detector positioning station Rasnik, and the beam phase and intensity monitor (together with a P-III team). Simulations of the B decays into vector mesons, for the High Level Trigger, were performed. The ALICE team has worked on the installation of the photon detector PHOS and tests with cosmic muons. Simulations of neutral pion reconstruction were performed. Preparation of the computing base for future large experiments - work within the Worldwide LHC Computing Grid was actively pursued by a dedicated team. In 2008, many activities were directed at information and popularization of LHC physics. Our department members actively

  19. 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.

  20. Networked event-triggered control: an introduction and research trends

    Science.gov (United States)

    Mahmoud, Magdi S.; Sabih, Muhammad

    2014-11-01

    A physical system can be studied as either continuous time or discrete-time system depending upon the control objectives. Discrete-time control systems can be further classified into two categories based on the sampling: (1) time-triggered control systems and (2) event-triggered control systems. Time-triggered systems sample states and calculate controls at every sampling instant in a periodic fashion, even in cases when states and calculated control do not change much. This indicates unnecessary and useless data transmission and computation efforts of a time-triggered system, thus inefficiency. For networked systems, the transmission of measurement and control signals, thus, cause unnecessary network traffic. Event-triggered systems, on the other hand, have potential to reduce the communication burden in addition to reducing the computation of control signals. This paper provides an up-to-date survey on the event-triggered methods for control systems and highlights the potential research directions.