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Sample records for lhcb calorimeter monitoring

  1. LHCb calorimeters high voltage system

    NASA Astrophysics Data System (ADS)

    Gilitsky, Yu.; Golutvin, A.; Konoplyannikov, A.; Lefrancois, J.; Perret, P.; Schopper, A.; Soldatov, M.; Yakimchuk, V.

    2007-02-01

    The calorimeter system in LHCb aims to identify electrons, photons and hadrons. All calorimeters are equipped with Hamamatsu photo tubes as devices for light to signal conversion. Eight thousand R7899-20 tubes are used for electromagnetic and hadronic calorimeters and two hundred 64 channels multi-anode R7600-00-M64 for Scintillator-Pad/Preshower detectors. The calorimeter high voltage (HV) system is based on a Cockroft Walton (CW) voltage converter and a control board connected to the Experiment Control System (ECS) by serial bus. The base of each photomultiplier tube (PMT) is built with a high voltage converter and constructed on an individual printed circuit board, using compact surface mount components. The base is attached directly to the PMT. There are no HV cables in the system. A Field Programmable Gate Array (FPGA) is used on the control board as an interface between the ECS and the 200 control channels. The FPGA includes also additional functionalities allowing automated monitoring and ramp up of the high voltage values. This paper describes the HV system architecture, some technical details of the electronics implementation and summarizes the system performance. This safe and low power consumption HV electronic system for the photomultiplier tubes can be used for various biomedical apparatus too.

  2. Triggering with the LHCb calorimeters

    NASA Astrophysics Data System (ADS)

    Lefevre, Regis; LHCb Collaboration

    2009-04-01

    The LHCb experiment at the LHC has been conceived to pursue high precision studies of CP violation and rare phenomena in b hadron decays. The online selection is crucial in LHCb and relies on the calorimeters to trigger on high transverse energy electrons, photons, π0 and hadrons. In this purpose a dedicated electronic has been realized. The calorimeter trigger system has been commissioned and is used to trigger on cosmic muons before beams start circulating in the LHC. When the LHC will start, it will also provide a very useful interaction trigger.

  3. Dataflow Monitoring in LHCb

    NASA Astrophysics Data System (ADS)

    Svantesson, D.; Schwemmer, R.; Liu, G.; Neufeld, N.

    2011-12-01

    The LHCb data-flow starts from the collection of event-fragments from more than 300 read-out boards at a rate of 1 MHz. These data are moved through a large switching network consisting of more than 50 routers to an event-filter farm of up to 1500 servers. Accepted events are sent through a dedicated network to storage collection nodes which concatenate accepted events in to files and transfer them to mass-storage. At nominal conditions more than 30 million packets enter and leave the network every second. Precise monitoring of this data-flow down to the single packet counter is essential to trace rare but systematic sources of data-loss. We have developed a comprehensive monitoring framework allowing to verify the data-flow at every level using a variety of standard tools and protocols such as sFlow, SNMP and custom software based on the LHCb Experiment Control System frame-work. This paper starts from an analysis of the data-flow and the involved hardware and software layers. From this analysis it derives the architecture and finally presents the implementation of this monitoring system.

  4. Study of response nonuniformity for the LHCb calorimeter module and the prototype of the CBM calorimeter module

    SciTech Connect

    Korolko, I. E.; Prokudin, M. S.

    2009-02-15

    A spatial nonuniformity of the response to high-energy muons is studied in the modules of the LHCb electromagnetic calorimeter and the prototype of the calorimeter module with lead plates and scintillator tiles 0.5 mm thick. The nonuniformity of the response of the inner LHCb modules to 50-GeV electrons is also measured. Software is developed for a thorough simulation of light collection in scintillator plates of a shashlik calorimeter. A model is elaborated to describe light transmission from the initial scintillation to the wavelength-shifting fiber with a subsequent reradiation and propagation of light over the fiber to the photodetector. The results of the simulation are in good agreement with data.

  5. Calibration of the LHCb electromagnetic calorimeter via reconstructing the neutral-pion invariant mass

    SciTech Connect

    Belyaev, I. M. Golubkov, D. Yu. Egorychev, V. Yu. Polikarpov, S. M. Savrina, D. V.

    2015-12-15

    The calibration of the LHCb electromagnetic calorimeter is a multistep procedure aimed at reconstructing photon and electron energies to a precision not poorer than 2%. A method based on measuring the neutral-pion invariantmass is applied at the last step of this procedure. A regular application of this method makes it possible to improve substantially the resolution for particles that decay through channels featuring electrons and photons in the final state.

  6. Cesium monitoring system for ATLAS Tile Hadron Calorimeter

    NASA Astrophysics Data System (ADS)

    Starchenko, E.; Blanchot, G.; Bosman, M.; Cavalli-Sforza, M.; Karyukhin, A.; Kopikov, S.; Miagkov, A.; Nessi, M.; Shalimov, A.; Shalanda, N.; Soldatov, M.; Solodkov, A.; Soloviev, A.; Tsoupko-Sitnikov, V.; Zaitsev, A.

    2002-11-01

    A system to calibrate and monitor ATLAS Barrel Hadronic Calorimeter (TileCal) is under construction at CERN Laboratory. A movable radioactive source driven by a liquid flow travels through the calorimeter body deposing a known energy to the calorimeter cells. Extensive R&D studies have been carried out and the main system parameters are evaluated. The prototypes are currently used for quality check and inter-calibration of the TileCal modules. A distributed control system, hardware as well as corresponding on-line and off-line software is developed.

  7. Forward hadron calorimeter of European hybrid spectrometer monitoring system

    SciTech Connect

    Boratave, M.; Datsko, N.A.; David, J.; Ivanyushenkov, Y.M.; Kistenoev, E.P.; Vlasov, E.V.

    1985-11-01

    The light-monitoring system of the forward neutral-hadron calorimeter of the European hybrid spectrometer is described. A general block diagram of the system, the functional relationships of the modules, and the ideology of the mathematical support are presented. The calorimeter records neutral particles in momentum range of 10-400 MeV/c. The calorimeter consists of 200 identical counters in modules of four each in a 10 X 20 matrix. The counters are made from plastic scintillators interlayed by steel plates. Light is collected by means of a rod reemitter admitted along the counter axis.

  8. A purity monitor for the KEDR liquid krypton calorimeter

    NASA Astrophysics Data System (ADS)

    Evtushenko, P. N.; Kotov, K. Yu.; Maslennikov, A. L.; Peleganchuk, S. V.; Snopkov, R. G.; Rogozin, A. I.; Tikhonov, Yu. A.

    2016-06-01

    We present a purity monitor for the KEDR liquid krypton calorimeter. A new method is suggested based on the usage of a short pulse of a gas discharge as a source of ultraviolet radiation for the photoproduction of electrons in a drift cell of the monitor. This paper describes the design of the monitor, the results of experiments with gaseous and liquid krypton, as well as the experience of using the developed device in the process of krypton purification for the KEDR liquid krypton calorimeter.

  9. An LHCb general-purpose acquisition board for beam and background monitoring at the LHC

    NASA Astrophysics Data System (ADS)

    Alessio, F.; Guzik, Z.; Jacobsson, R.

    2011-01-01

    In this paper we will present an LHCb custom-made acquisition board which was developed for a continuous beam and background monitoring during LHC operations at CERN. The paper describes both the conceptual design and its performance, and concludes with results from the first period of beam operations at the LHC. The main purpose of the acquisition board is to process signals from a pair of beam pickups to continuously monitor the intensity of each bunch, and to monitor the phase of the arrival time of each proton bunch with respect to the LHC bunch clock. The extreme versatility of the board also allowed the LHCb experiment to build a high-speed and high-sensitivity readout system for a fast background monitor based on a pair of plastic scintillators. The board has demonstrated very good performance and proved to be conceptually valid during the first months of operations at the LHC. Connected to the beam pickups, it provides the LHCb experiment with a real-time measurement of the total intensity of each beam and of the arrival time of each beam at the LHCb Interaction Point. It also monitors the LHC filling scheme and the beam current per bunch at a continuous rate of 40 MHz, and assures a proper global timing of LHCb. The continuous readout of the scintillators at bunch clock speed provides the LHCb experiment with high-resolution information about the beam halo and fast losses during both injection and circulating beam. It has also provided valuable information to the LHC during machine commissioning with beam. Recent results also shows that it could contribute as a luminosity monitor independent from the LHCb experiment readout system. Beam, background and luminosity measurements are continuously fed back to the LHC in the data exchange framework between the experiments and the LHC machine aimed at improving efficiently the experimental conditions real-time.

  10. The LHCb Online Framework for Experiment Protection, and Global Operational Control and Monitoring

    NASA Astrophysics Data System (ADS)

    Alessio, F.; Jacobsson, R.; Schleich, S.

    2011-12-01

    The complexity and extreme parameters of the LHC, such as the stored energy, the collision frequency, the high risk of adverse background conditions and potentially damaging beam losses have demanded an unprecedented connectivity between the operation of the accelerator and the experiments at both hardware and software level. LHCb has been at the forefront of developing a software framework and hardware which connects to all of the LHC communication interfaces for timing, control and monitoring of the machine and beam parameters, in addition to its own local systems for beam and background monitoring. The framework also includes failsafe connectivity with the beam interlock system. The framework drives the global operation of the detector and is integrated into the readout control. It provides the shifters with the tools needed to take fast and well-guided decisions to run the LHCb experiment safely and efficiently. In particular, it has allowed the detector to be operated with only two shifters already at the LHC pilot run. The requirements include reliability and clarity for the shifters, and the possibility to retrieve the past conditions for offline analysis. All essential parameters are archived and an interactive analysis tool has been developed which provides overviews of the experimental performance and which allows post-analysis of any anomaly in the operation. This paper describes the architecture and the many functions, including the basis of the automation of the LHCb operational procedure and detector controls, and the information exchange between LHCb and the LHC, and finally the shifter and expert tools for monitoring the experimental conditions.

  11. Relative Gain Monitoring of the GlueX Calorimeters

    SciTech Connect

    Anassontzis, Efstratios G.; Kourkoumelis, C.; Vasileiadis, G.; Voulgaris, G.; Kappos, E.; Beattie, T.; Krueger, S.; Lolos, G. J.; Papandreou, Z.; Semenov, A. Yu.; Frye, John M.; Leckey, John P.; Shepherd, Matt; Bogart, T.; Smith, Elton S.

    2014-02-01

    The relative gain of the photodetectors for the GlueX Barrel and Forward calorimeters will be monitored using modular LED driver systems. The BCAL system consists of a global controller that feeds power, bias voltage and trigger signals to 96 local controllers situated at the ends of the 48 BCAL modules, which drive 40 LEDs associated with the 40 light guides at the end of each module. The FCAL system consists also of a global controller, a local controller for each acrylic quadrant covering the face of the FCAL, and ten 4-LED pulser boards per local controller connected in a star configuration along the edges of the acrylic panes. The respective systems are currently being installed on the detectors and their tested performance is presented herein.

  12. Potentials and limitations of miniaturized calorimeters for bioprocess monitoring.

    PubMed

    Maskow, Thomas; Schubert, Torsten; Wolf, Antje; Buchholz, Friederike; Regestein, Lars; Buechs, Jochen; Mertens, Florian; Harms, Hauke; Lerchner, Johannes

    2011-10-01

    In theory, heat production rates are very well suited for analysing and controlling bioprocesses on different scales from a few nanolitres up to many cubic metres. Any bioconversion is accompanied by a production (exothermic) or consumption (endothermic) of heat. The heat is tightly connected with the stoichiometry of the bioprocess via the law of Hess, and its rate is connected to the kinetics of the process. Heat signals provide real-time information of bioprocesses. The combination of heat measurements with respirometry is theoretically suited for the quantification of the coupling between catabolic and anabolic reactions. Heat measurements have also practical advantages. Unlike most other biochemical sensors, thermal transducers can be mounted in a protected way that prevents fouling, thereby minimizing response drifts. Finally, calorimetry works in optically opaque solutions and does not require labelling or reactants. It is surprising to see that despite all these advantages, calorimetry has rarely been applied to monitor and control bioprocesses with intact cells in the laboratory, industrial bioreactors or ecosystems. This review article analyses the reasons for this omission, discusses the additional information calorimetry can provide in comparison with respirometry and presents miniaturization as a potential way to overcome some inherent weaknesses of conventional calorimetry. It will be discussed for which sample types and scientific question miniaturized calorimeter can be advantageously applied. A few examples from different fields of microbiological and biotechnological research will illustrate the potentials and limitations of chip calorimetry. Finally, the future of chip calorimetry is addressed in an outlook. PMID:21808971

  13. LHCbDirac: distributed computing in LHCb

    NASA Astrophysics Data System (ADS)

    Stagni, F.; Charpentier, P.; Graciani, R.; Tsaregorodtsev, A.; Closier, J.; Mathe, Z.; Ubeda, M.; Zhelezov, A.; Lanciotti, E.; Romanovskiy, V.; Ciba, K. D.; Casajus, A.; Roiser, S.; Sapunov, M.; Remenska, D.; Bernardoff, V.; Santana, R.; Nandakumar, R.

    2012-12-01

    We present LHCbDirac, an extension of the DIRAC community Grid solution that handles LHCb specificities. The DIRAC software has been developed for many years within LHCb only. Nowadays it is a generic software, used by many scientific communities worldwide. Each community wanting to take advantage of DIRAC has to develop an extension, containing all the necessary code for handling their specific cases. LHCbDirac is an actively developed extension, implementing the LHCb computing model and workflows handling all the distributed computing activities of LHCb. Such activities include real data processing (reconstruction, stripping and streaming), Monte-Carlo simulation and data replication. Other activities are groups and user analysis, data management, resources management and monitoring, data provenance, accounting for user and production jobs. LHCbDirac also provides extensions of the DIRAC interfaces, including a secure web client, python APIs and CLIs. Before putting in production a new release, a number of certification tests are run in a dedicated setup. This contribution highlights the versatility of the system, also presenting the experience with real data processing, data and resources management, monitoring for activities and resources.

  14. The calibration and monitoring system for the PHENIX lead-scintillator electromagnetic calorimeter

    SciTech Connect

    David, G.; Kistenev, E.; Stoll, S.

    1997-11-01

    A system for calibrating the PHENIX lead-scintillator electromagnetic calorimeter modules with cosmic rays and monitoring the stability during operation is described. The system is based on a UV laser which delivers light to each module through a network of optical fibers and splutters and is monitored at various points with silicon and vacuum photodiodes. Results are given from a prototype system which used a nitrogen laser to set the initial phototube gains and to establish the energy calibration of calorimeter modules and monitor their stability. A description of the final system to be used in PHENIX based on a high power YAG laser, is also given.

  15. The calibration and monitoring system for the PHENIX lead-scintillator electromagnetic calorimeter

    SciTech Connect

    David, G.; Kistenev, E.; Stoll, S.; White, S.; Woody, C.; Bazilevsky, A.; Belikov, S.; Chernichenkov, S.; Denisov, A.; Gilitzky, Y.; Kochetkov, V.; Melnikov, Y.; Onuchin, V.; Semenov, A.; Shelikhov, V.; Soldatov, A.

    1998-11-01

    A system for calibrating the PHENIX lead-scintillator electromagnetic calorimeter modules with cosmic rays and monitoring the stability during operation is described. The system is based on a UV laser which delivers light to each module through a network of optical fibers and splitters and is monitored at various points with silicon and vacuum photodiodes. Results are given from a prototype system which used a nitrogen laser to set the initial phototube gains and to establish the energy calibration of calorimeter modules and monitor their stability. A description of the final system to be used in PHENIX, based on a high power YAG laser, is also given. {copyright} {ital 1998 American Institute of Physics.}

  16. A cryogenic monitor system for the Liquid Argon Calorimeter in the SLD detector

    SciTech Connect

    Fox, M.J.; Fox, J.D.

    1988-10-01

    This paper describes the monitoring electronics system design for the Liquid Argon Calorimeter (LAC) portion of the SLD detector. This system measures temperatures and liquid levels inside the LAC cryostat and transfers the results over a fiber-optic serial link to an external monitoring computer. System requirements, unique design constraints, and detailed analog, digital and software designs are presented. Fault tolerance and the requirement for a single design to work in several different operating environments are discussed. 4 refs., 3 figs., 1 tab.

  17. The monitoring and data quality assessment of the ATLAS liquid argon calorimeter

    NASA Astrophysics Data System (ADS)

    Simard, Olivier; ATLAS Liquid Argon Calorimeter Group

    2015-02-01

    The ATLAS experiment is designed to study the proton-proton (pp) collisions produced at the Large Hadron Collider (LHC) at CERN. Liquid argon (LAr) sampling calorimeters are used for all electromagnetic calorimetry in the pseudo-rapidity region |η| < 3.2, as well as for hadronic calorimetry in the range 1.5 < |η| < 4.9. The electromagnetic calorimeters use lead as passive material and are characterized by an accordion geometry that allows a fast and uniform response without azimuthal gaps. Copper and tungsten were chosen as passive material for the hadronic calorimetry; while a classic parallel-plate geometry was adopted at large polar angles, an innovative design based on cylindrical electrodes with thin liquid argon gaps is employed at low angles, where the particle flux is higher. All detectors are housed in three cryostats maintained at about 88.5 K. The 182,468 cells are read out via front-end boards housed in on-detector crates that also contain monitoring, calibration, trigger and timing boards. In the first three years of LHC operation, approximately 27 fb-1 of pp collision data were collected at centre-of-mass energies of 7-8 TeV. Throughout this period, the calorimeter consistently operated with performances very close to specifications, with high data-taking efficiency. This is in large part due to a sophisticated data monitoring procedure designed to quickly identify issues that would degrade the detector performance, to ensure that only the best quality data are used for physics analysis. After a description of the detector design, main characteristics and operation principles, this paper details the data quality assessment procedures developed during the 2011 and 2012 LHC data-taking periods, when more than 98% of the luminosity recorded by ATLAS had high quality LAr calorimeter data suitable for physics analysis.

  18. The Monitoring and Calibration Web Systems for the ATLAS Tile Calorimeter Data Quality Analysis

    NASA Astrophysics Data System (ADS)

    Sivolella, A.; Maidantchik, C.; Ferreira, F.

    2012-12-01

    The Tile Calorimeter (TileCal) is one of the ATLAS sub-detectors. The read-out is performed by about 10,000 PhotoMultiplier Tubes (PMTs). The signal of each PMT is digitized by an electronic channel. The Monitoring and Calibration Web System (MCWS) supports the data quality analysis of the electronic channels. This application was developed to assess the detector status and verify its performance. It can provide to the user the list of TileCal known problematic channels, that is stored in the ATLAS condition database (COOL DB). The bad channels list guides the data quality validator in identifying new problematic channels and is used in data reconstruction and the system allows to update the channels list directly in the COOL database. MCWS can generate summary results, such as eta-phi plots and comparative tables of the masked channels percentage. Regularly, during the LHC (Large Hadron Collider) shutdown a maintenance of the detector equipments is performed. When a channel is repaired, its calibration constants stored in the COOL database have to be updated. Additionally MCWS system manages the update of these calibration constants values in the COOL database. The MCWS has been used by the Tile community since 2008, during the commissioning phase, and was upgraded to comply with ATLAS operation specifications. Among its future developments, it is foreseen an integration of MCWS with the TileCal control Web system (DCS) in order to identify high voltage problems automatically.

  19. Distributed analysis at LHCb

    NASA Astrophysics Data System (ADS)

    Williams, Mike; Egede, Ulrik; Paterson, Stuart; LHCb Collaboration

    2011-12-01

    The distributed analysis experience to date at LHCb has been positive: job success rates are high and wait times for high-priority jobs are low. LHCb users access the grid using the GANGA job-management package, while the LHCb virtual organization manages its resources using the DIRAC package. This clear division of labor has benefitted LHCb and its users greatly; it is a major reason why distributed analysis at LHCb has been so successful. The newly formed LHCb distributed analysis support team has also proved to be a success.

  20. An LED-Based Gain Monitoring System for the PrimEx Hybrid Calorimeter at Jefferson Lab

    NASA Astrophysics Data System (ADS)

    Underwood, Jarreas

    2003-10-01

    The PrimEx Collaboration is preparing to perform a high precision ( ˜ 1.4%) measurement of the neutral pion decay width through two gamma decay mode. Knowledge of the pion decay width with such high accuracy will provide a stringent test of the fundamental symmetry breaking issue in QCD - the chiral anomaly. The theoretical prediction of the decay width is precise, and the 1.4% level measurement in PrimEx is adequate for this test. Pions will be produced in nuclear targets by the coherent photoproduction in the Coulomb field of a nucleus at small angles (Primakoff effect). The energy and coordinates of the resultant decay photons will be detected in a high resolution HYbrid CALorimeter (HYCAL) which consists of about 1200 lead tungstate crystal scintillators surrounded by ˜ 600 lead glass Cherenkov counters. HYCAL will be furnished with precise ˜ 0.1% gain monitoring system based on blue super-bright light emitting diodes. A 700-channel prototype system has been constructed for the prototype HYCAL-0 calorimeter. This system has been tested for both long-term stability and performance in the CEBAF photon beam. Additionally, fluctuations in the calorimeter high voltages were simulated during the beam test. The results of these tests will be presented. This project is being supported by NSF grants PHY-0079840 and PHY-0072466

  1. The PHENIX electromagnetic calorimeter

    SciTech Connect

    Kistenev, E.; White, S.; Belikov, S.; Kochetkov, V.

    1993-12-31

    The main features of the Phenix EM calorimeter are presented. This a Pb/scintillator calorimeter with ``shish-kebab`` fiber readout, designed for low energy electron and photon measurements. Prototype calorimeters have been built with longitudinal segmentation, {approximately} 100 psec time of flight resolution and 8% energy resolution at 1GeV/c. The laser based monitoring system which has been incorporated into large scale prototypes is described. The dependence of light yield on fiber choice and scintillator surface preparation has been studied.

  2. The LHCb Run Control

    NASA Astrophysics Data System (ADS)

    Alessio, F.; Barandela, M. C.; Callot, O.; Duval, P.-Y.; Franek, B.; Frank, M.; Galli, D.; Gaspar, C.; Herwijnen, E. v.; Jacobsson, R.; Jost, B.; Neufeld, N.; Sambade, A.; Schwemmer, R.; Somogyi, P.

    2010-04-01

    LHCb has designed and implemented an integrated Experiment Control System. The Control System uses the same concepts and the same tools to control and monitor all parts of the experiment: the Data Acquisition System, the Timing and the Trigger Systems, the High Level Trigger Farm, the Detector Control System, the Experiment's Infrastructure and the interaction with the CERN Technical Services and the Accelerator. LHCb's Run Control, the main interface used by the experiment's operator, provides access in a hierarchical, coherent and homogeneous manner to all areas of the experiment and to all its sub-detectors. It allows for automated (or manual) configuration and control, including error recovery, of the full experiment in its different running modes. Different instances of the same Run Control interface are used by the various sub-detectors for their stand-alone activities: test runs, calibration runs, etc. The architecture and the tools used to build the control system, the guidelines and components provided to the developers, as well as the first experience with the usage of the Run Control will be presented

  3. LHCb Online event processing and filtering

    NASA Astrophysics Data System (ADS)

    Alessio, F.; Barandela, C.; Brarda, L.; Frank, M.; Franek, B.; Galli, D.; Gaspar, C.; Herwijnen, E. v.; Jacobsson, R.; Jost, B.; Köstner, S.; Moine, G.; Neufeld, N.; Somogyi, P.; Stoica, R.; Suman, S.

    2008-07-01

    The first level trigger of LHCb accepts one million events per second. After preprocessing in custom FPGA-based boards these events are distributed to a large farm of PC-servers using a high-speed Gigabit Ethernet network. Synchronisation and event management is achieved by the Timing and Trigger system of LHCb. Due to the complex nature of the selection of B-events, which are the main interest of LHCb, a full event-readout is required. Event processing on the servers is parallelised on an event basis. The reduction factor is typically 1/500. The remaining events are forwarded to a formatting layer, where the raw data files are formed and temporarily stored. A small part of the events is also forwarded to a dedicated farm for calibration and monitoring. The files are subsequently shipped to the CERN Tier0 facility for permanent storage and from there to the various Tier1 sites for reconstruction. In parallel files are used by various monitoring and calibration processes running within the LHCb Online system. The entire data-flow is controlled and configured by means of a SCADA system and several databases. After an overview of the LHCb data acquisition and its design principles this paper will emphasize the LHCb event filter system, which is now implemented using the final hardware and will be ready for data-taking for the LHC startup. Control, configuration and security aspects will also be discussed.

  4. LHCb GPU acceleration project

    NASA Astrophysics Data System (ADS)

    Badalov, A.; Cámpora, D.; Neufeld, N.; Vilasís-Cardona, X.

    2016-01-01

    The LHCb detector is due to be upgraded for processing high-luminosity collisions, which will increase data bandwidth to the event filter farm from 100 GB/s to 4 TB/s, encouraging us to look for new ways of accelerating Online reconstruction. The Coprocessor Manager is a new framework for integrating LHCb's existing computation pipelines with massively parallel algorithms running on GPUs and other accelerators. This paper describes the system and analyzes its performance.

  5. The LHCb Upgrade

    NASA Astrophysics Data System (ADS)

    Jacobsson, Richard

    2013-11-01

    With the demonstration that LHCb can successfully perform forward precision measurements with event pileup, the operation and trigger strategy evolved significantly during the LHC Run 1 allowing LHCb to collect over 3fb-1 at centre-of-mass energies of 7TeV and 8TeV. Increased bandwidth opened the door for LHCb to extend the physics program. The additional statistics and well managed systematic effects together with the stable trigger and data taking conditions have led to a very large number of world-class measurements and dominance in heavy flavour physics [1], in addition to a reputation of an excellent forward general purpose detector at the LHC. Long Shutdown (LS) 1 (2013-2014) will allow LHCb to fully explore the large statistics collected and prepare LHCb for Run 2 (2015 - 2017). However, even after an additional expected integrated luminosity of 5-6 fb-1 in Run 2, many of the LHCb precision measurements will remain limited by statistics, and some exploratory physics modes will not even be accessible yet. With the need for reconstructing the event topology in order to efficiently trigger on the beauty and the charm hadrons decays, the current 1 MHz readout limit is the main bottle neck to run at higher luminosity and with higher trigger efficiencies. LHCb will therefore undergo a major upgrade in LS 2 ( 2018 - 2019) aimed at collecting an order of magnitude more data by 2028. The upgrade consists of a full readout at the LHC bunch crossing rate ( 40 MHz) with the ultimate flexibility of only a software trigger. In order to increase the instantaneous luminosity up to 2x1033cm-2s-1, several sub-detector upgrades are also underway to cope with the higher occupancies and radiation dose.

  6. Photon calorimeter

    DOEpatents

    Chow, Tze-Show

    1988-04-22

    A photon calorimeter is provided that comprises a laminar substrate that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating, that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions, are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly. 4 figs.

  7. Photon Calorimeter

    DOEpatents

    Chow, Tze-Show

    1989-01-01

    A photon calorimeter (20, 40) is provided that comprises a laminar substrate (10, 22, 42) that is uniform in density and homogeneous in atomic composition. A plasma-sprayed coating (28, 48, 52), that is generally uniform in density and homogeneous in atomic composition within the proximity of planes that are parallel to the surfaces of the substrate, is applied to either one or both sides of the laminar substrate. The plasma-sprayed coatings may be very efficiently spectrally tailored in atomic number. Thermocouple measuring junctions (30, 50, 54) are positioned within the plasma-sprayed coatings. The calorimeter is rugged, inexpensive, and equilibrates in temperature very rapidly.

  8. Isothermal Calorimeter

    NASA Technical Reports Server (NTRS)

    Rowlette, John J.

    1990-01-01

    Pressure-feedback signal indicates rate of heating. Improved isothermal calorimeter measures rate of heating in object under test. Called "isothermal" because chamber holding object and its environment maintained at or near constant temperature to minimize spurious tranfers of heat introducing errors into measurements. When item under test generates heat, rate of boiling and pressure in inner chamber increase. Servo-valve opens wider to maintain preset differential pressure. Valve-control voltage used as measure of rate of heating.

  9. Electromagnetic Calorimeter for Hades Experiment

    NASA Astrophysics Data System (ADS)

    Kugler, A.; Blume, C.; Czyžycki, W.; Epple, E.; Fabbietti, L.; Galatyuk, T.; Golubeva, M.; Guber, F.; Hlaváč, S.; Ivashkin, A.; Kajetanowic, M.; Kardan, B.; Koenig, W.; Lapidus, K.; Lisowski, E.; Pietraszko, J.; Reshetin, A.; Rost, A.; Salabura, P.; Sobolev, Y. G.; Svoboda, O.; Tlusty, P.; Traxler, M.

    2014-06-01

    Electromagnetic calorimeter (ECAL) is being developed to complement the dilepton spectrometer HADES currently operating at GSI Darmstadt, Germany. ECAL will enable the HADES@FAIR experiment to measure data on neutral meson production in heavy ion collisions at the energy range of 2-10 A GeV on the beam of future accelerator SIS100@FAIR. The calorimeter will also improve the electron-hadron separation and will as well be used for the detection of photons from strange resonances in elementary and heavy ion reactions. Calorimeter modules constructed of lead glass Cherenkov counter, photomultiplier, HV divider and optical fiber are described in the detail. Two prototypes of novel front-end electronics based on TRB3 are presented. A dedicated LED based system being developed to monitor the stability of the calorimeter during beamtime is introduced as well.

  10. The LHCb Turbo stream

    NASA Astrophysics Data System (ADS)

    Puig, A.

    2016-07-01

    The LHCb experiment will record an unprecedented dataset of beauty and charm hadron decays during Run II of the LHC, set to take place between 2015 and 2018. A key computing challenge is to store and process this data, which limits the maximum output rate of the LHCb trigger. So far, LHCb has written out a few kHz of events containing the full raw sub-detector data, which are passed through a full offline event reconstruction before being considered for physics analysis. Charm physics in particular is limited by trigger output rate constraints. A new streaming strategy includes the possibility to perform the physics analysis with candidates reconstructed in the trigger, thus bypassing the offline reconstruction. In the Turbo stream the trigger will write out a compact summary of physics objects containing all information necessary for analyses. This will allow an increased output rate and thus higher average efficiencies and smaller selection biases. This idea will be commissioned and developed during 2015 with a selection of physics analyses. It is anticipated that the turbo stream will be adopted by an increasing number of analyses during the remainder of LHC Run II (2015-2018) and ultimately in Run III (starting in 2020) with the upgraded LHCb detector.

  11. The LHCb Turbo Stream

    NASA Astrophysics Data System (ADS)

    Benson, Sean; Gligorov, Vladimir; Vesterinen, Mika Anton; Williams, John Michael

    2015-12-01

    The LHCb experiment will record an unprecedented dataset of beauty and charm hadron decays during Run II of the LHC, set to take place between 2015 and 2018. A key computing challenge is to store and process these datasets, which will limit the maximum output rate of the LHCb trigger. So far, LHCb has written out a few kHz of events containing the full raw sub-detector data, which are passed through a full offline event reconstruction before being considered for physics analysis. Charm physics in particular is limited by trigger output rate constraints. A new streaming strategy includes the possibility to perform the physics analysis with candidates reconstructed in the trigger, thus bypassing the offline reconstruction and discarding the raw event. In the Turbo stream the trigger will write out a compact summary of physics objects containing all information necessary for analyses, and this will allow an increased output rate and thus higher average efficiencies and smaller selection biases. This idea will be commissioned and developed during 2015 with a selection of physics analyses. It is anticipated that the turbo stream will be adopted by an increasing number of analyses during the remainder of LHC Run II (2015-2018) and ultimately in Run III (starting in 2020) with the upgraded LHCb detector.

  12. The LHCb Muon System

    SciTech Connect

    Baldini, W.

    2005-10-12

    In this paper is described the design, the construction and the performances of several Multi Wire Proportional Chamber prototypes built for the LHCb Muon system. In particular we report results for detection efficiency, time resolution, high rate performances and ageing effect measured at the CERN T11 test beam area and at the high irradiation ENEA Casaccia Calliope Facility.

  13. The LHCb Silicon Tracker

    NASA Astrophysics Data System (ADS)

    Tobin, Mark

    2013-12-01

    The LHCb experiment is designed to perform high-precision measurements of CP violation and search for new physics using the enormous flux of beauty and charm hadrons produced at the LHC. The LHCb detector is a single-arm spectrometer with excellent tracking and particle identification capabilities. The Silicon Tracker is part of the tracking system and measures very precisely the particle trajectories coming from the interaction point in the region of high occupancies around the beam axis. The LHCb Silicon Tracker covers a total sensitive area of about 12 m2 using silicon micro-strip detectors with long readout strips. It consists of one four-layer tracking station before the LHCb dipole magnet and three stations after. The detector has performed extremely well since the start of the LHC operation despite the fact that the experiment is collecting data at instantaneous luminosities well above the design value. This paper reports on the operation and performance of the Silicon Tracker during the Physics data taking at the LHC during the last two years.

  14. DSWA calorimeter bomb experiments

    SciTech Connect

    Cunningham, B

    1998-10-01

    Two experiments were performed in which 25 grams of TNT were detonated inside an expended detonation calorimeter bomb. The bomb had a contained volume of approximately 5.28 liters. In the first experiment, the bomb was charged with 3 atmospheres of nitrogen. In the second, it was charged with 2.58 atmospheres (23.1 psi gage) of oxygen. In each experiment pressure was monitored over a period of approximately 1200 microseconds after the pulse to the CDU. Monitoring was performed via two 10,000 psi 102AO3 PCB high frequency pressure transducers mounted symmetrically in the lid of the calorimeter bomb. Conditioners used were PCB 482As. The signals from the transducers were recorded in digital format on a multi channel Tektronix scope. The sampling frequency was 10 Mhz (10 samples per microsecond). After a period of cooling following detonation, gas samples were taken and were subsequently submitted for analysis using gas mass spectrometry. Due to a late request for post shot measurement, it was only possible to make a rough estimate of the weight of debris (carbon) remaining in the calorimeter bomb following the second experiment.

  15. LHCb Conditions database operation assistance systems

    NASA Astrophysics Data System (ADS)

    Clemencic, M.; Shapoval, I.; Cattaneo, M.; Degaudenzi, H.; Santinelli, R.

    2012-12-01

    The Conditions Database (CondDB) of the LHCb experiment provides versioned, time dependent geometry and conditions data for all LHCb data processing applications (simulation, high level trigger (HLT), reconstruction, analysis) in a heterogeneous computing environment ranging from user laptops to the HLT farm and the Grid. These different use cases impose front-end support for multiple database technologies (Oracle and SQLite are used). Sophisticated distribution tools are required to ensure timely and robust delivery of updates to all environments. The content of the database has to be managed to ensure that updates are internally consistent and externally compatible with multiple versions of the physics application software. In this paper we describe three systems that we have developed to address these issues. The first system is a CondDB state tracking extension to the Oracle 3D Streams replication technology, to trap cases when the CondDB replication was corrupted. Second, an automated distribution system for the SQLite-based CondDB, providing also smart backup and checkout mechanisms for the CondDB managers and LHCb users respectively. And, finally, a system to verify and monitor the internal (CondDB self-consistency) and external (LHCb physics software vs. CondDB) compatibility. The former two systems are used in production in the LHCb experiment and have achieved the desired goal of higher flexibility and robustness for the management and operation of the CondDB. The latter one has been fully designed and is passing currently to the implementation stage.

  16. Ensuring GRID resource availability with the SAM framework in LHCb

    NASA Astrophysics Data System (ADS)

    Closier, J.; Paterson, S.; Santinelli, R.

    2008-07-01

    The LHCb experiment has chosen to use the SAM framework (Service Availability Monitoring Environment from EGEE-II) [1] make extensive tests of the LHCb environment at all the accessible grid resources. The availability and the proper definition of the local Computing and Storage Elements, user interfaces as well as the WLCG software environment are checked. The SAM framework is also used to pre-install the LHCb applications in the shared software area provided by each site. The deployment of the LHCb applications is based on a python tool developed inside the experiment. It is used for software management including incremental installation of interdependent packages and clean package removal. After the application software is installed a validation test of the whole MC chain is run. According to the results of the experiment specific SAM tests, the sites are (re)integrated into the LHCb production system managed by DIRAC [2]. The possibility of automated dynamic site certification using the SAM test suite is explored. This paper will describe the various ways of the LHCb use of the SAM framework. Practical experience in the recent production runs, current limitations and future developments will be presented.

  17. The LHCb silicon tracker

    NASA Astrophysics Data System (ADS)

    Adeva, B.; Agari, M.; Bauer, C.; Baumeister, D.; Bay, A.; Bernhard, R. P.; Bernet, R.; Blouw, J.; Carron, B.; Ermoline, Y.; Esperante, D.; Frei, R.; Gassner, J.; Hofmann, W.; Jimenez-Otero, S.; Knöpfle, K. T.; Köstner, S.; Lehner, F.; Löchner, S.; Lois, C.; Needham, M.; Pugatch, V.; Schmelling, M.; Schwingenheuer, B.; Siegler, M.; Steinkamp, O.; Straumann, U.; Tran, M. T.; Vazquez, P.; Vollhardt, A.; Volyanskyy, D.; Voss, H.

    2005-07-01

    LHCb is a dedicated B-physics and CP-violation experiment for the Large Hadron Collider at CERN. Efficient track reconstruction and excellent trigger performances are essential in order to exploit fully its physics potential. Silicon strip detectors providing fast signal generation, high resolution and fine granularity are used for this purpose in the large area Trigger Tracker station in front of the spectrometer magnet and the LHCb Inner Tracker covering the area close to the beam pipe behind the magnet. Long read-out strips of up to 38 cm are used together with fast signal shaping adapted to the 25 ns LHC bunch crossing. The design of these tracking stations, the silicon sensor strip geometries and the latest test results are presented here.

  18. LHCb distributed conditions database

    NASA Astrophysics Data System (ADS)

    Clemencic, M.

    2008-07-01

    The LHCb Conditions Database project provides the necessary tools to handle non-event time-varying data. The main users of conditions are reconstruction and analysis processes, which are running on the Grid. To allow efficient access to the data, we need to use a synchronized replica of the content of the database located at the same site as the event data file, i.e. the LHCb Tier1. The replica to be accessed is selected from information stored on LFC (LCG File Catalog) and managed with the interface provided by the LCG developed library CORAL. The plan to limit the submission of jobs to those sites where the required conditions are available will also be presented. LHCb applications are using the Conditions Database framework on a production basis since March 2007. We have been able to collect statistics on the performance and effectiveness of both the LCG library COOL (the library providing conditions handling functionalities) and the distribution framework itself. Stress tests on the CNAF hosted replica of the Conditions Database have been performed and the results will be summarized here.

  19. LHCb Topological Trigger Reoptimization

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    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.

  20. The LHCb VELO upgrade

    NASA Astrophysics Data System (ADS)

    Rodríguez Pérez, Pablo

    2013-12-01

    LHCb is a forward spectrometer experiment dedicated to the study of new physics in the decays of beauty and charm hadrons produced in proton collisions at the Large Hadron Collider (LHC) at CERN. The VErtex LOcator (VELO) is the microstrip silicon detector surrounding the interaction point, providing tracking and vertexing measurements. The upgrade of the LHCb experiment, planned for 2018, will increase the luminosity up to 2×1033 cm-2 s-1 and will perform the readout as a trigger-less system with an event rate of 40 MHz. Extremely non-uniform radiation doses will reach up to 5×1015 1 MeV neq/cm2 in the innermost regions of the VELO sensors, and the output data bandwidth will be increased by a factor of 40. An upgraded detector is under development based in a pixel sensor of the Timepix/Medipix family, with 55 × 55 μm2 pixels. In addition a microstrip solution with finer pitch, higher granularity and thinner than the current detector is being developed in parallel. The current status of the VELO upgrade program will be described together with recent testbeam results.

  1. Performance of the ATLAS Tile Calorimeter

    NASA Astrophysics Data System (ADS)

    Cole, Stephe

    2013-04-01

    The Tile Calorimeter is the central section (0 < |η| < 1.7) of the ATLAS hadronic calorimeter. It is a key detector for the measurement of hadrons, jets, tau leptons decaying hadronically, and missing transverse energy. Because of its very good signal to noise ratio it is also useful for the identification and reconstruction of muons. The calorimeter consists of thin steel plates and 460,000 scintillating tiles configured into 4900 cells, each viewed by two photomultipliers. The calorimeter response is monitored to better than 1% using radioactive source, laser, and electronic charge injection systems. The calibration and performance of the calorimeter have been established through test beam measurements, cosmic ray muons and the large sample of pp collisions acquired during 2011 and 2012. Results on the calorimeter performance will be presented, including the absolute energy scale, time resolution, and associated stabilities. These results demonstrate that the Tile Calorimeter is performing well within the design requirements and is giving essential input to the physics results.

  2. The LHCb VELO upgrade

    NASA Astrophysics Data System (ADS)

    Dosil Suárez, Álvaro

    2016-07-01

    The upgrade of the LHCb experiment, planned for 2019, will transform the experiment to a trigger-less system reading out the full detector at 40 MHz event rate. All data reduction algorithms will be executed in a high-level software farm. The upgraded detector will run at luminosities of 2×1033 cm-2 s-1 and probe physics beyond the Standard Model in the heavy flavour sector with unprecedented precision. The Vertex Locator (VELO) is the silicon vertex detector surrounding the interaction region. The current detector will be replaced with a hybrid pixel system equipped with electronics capable of reading out at 40 MHz. The detector comprises silicon pixel sensors with 55×55 μm2 pitch, read out by the VeloPix ASIC, based on the TimePix/MediPix family. The hottest region will have pixel hit rates of 900 Mhits/s yielding a total data rate more than 3 Tbit/s for the upgraded VELO. The detector modules are located in a separate vacuum, separated from the beam vacuum by a thin custom made foil. The detector halves are retracted when the beams are injected and closed at stable beams, positioning the first sensitive pixel at 5.1 mm from the beams. The material budget will be minimised by the use of evaporative CO2 coolant circulating in microchannels within 400 μm thick silicon substrates.

  3. The ATLAS Forward Calorimeter

    NASA Astrophysics Data System (ADS)

    Artamonov, A.; Bailey, D.; Belanger, G.; Cadabeschi, M.; Chen, T.-Y.; Epshteyn, V.; Gorbounov, P.; Joo, K. K.; Khakzad, M.; Khovanskiy, V.; Krieger, P.; Loch, P.; Mayer, J.; Neuheimer, E.; Oakham, F. G.; O'Neill, M.; Orr, R. S.; Qi, M.; Rutherfoord, J.; Savine, A.; Schram, M.; Shatalov, P.; Shaver, L.; Shupe, M.; Stairs, G.; Strickland, V.; Tompkins, D.; Tsukerman, I.; Vincent, K.

    2008-02-01

    Forward calorimeters, located near the incident beams, complete the nearly 4π coverage for high pT particles resulting from proton-proton collisions in the ATLAS detector at the Large Hadron Collider at CERN. Both the technology and the deployment of the forward calorimeters in ATLAS are novel. The liquid argon rod/tube electrode structure for the forward calorimeters was invented specifically for applications in high rate environments. The placement of the forward calorimeters adjacent to the other calorimeters relatively close to the interaction point provides several advantages including nearly seamless calorimetry and natural shielding for the muon system. The forward calorimeter performance requirements are driven by events with missing ET and tagging jets.

  4. A heat flow calorimeter

    NASA Technical Reports Server (NTRS)

    Johnston, W. V.

    1973-01-01

    Reaction mechanism for nickel-cadmium cell is not known well enough to allow calculation of heat effects. Calorimeter can measure heat absorbed or evolved in cell, by determining amount of external heat that must be supplied to calorimeter to maintain constant flow isothermal heat sink.

  5. Calorimeter Data Acquisition and Reporting Software

    Energy Science and Technology Software Center (ESTSC)

    1998-08-27

    The calorimeter Data Acquisition and Reporting Program performs the calculations necessary to calculate the calorimetric sample results in grams and provide a printable report for up to twelve Mound Calorimeters. To determine a standard''s wattage or sample gram fill, the reporting program retrieves the output voltage from the power supply at the calorimeter and a temperature resistant resistor via a voltmeter and digital input card in a Hewlett Packard Data Acquisition Unit (DAQ). From themore » retrieved voltage data, the reporting program can calculate a standard''s wattage output and sample gram fill. The reporting program also determines equilibrium (stability) by performing a stability algorithm bassed on user defined slope an/or sigma values for the previous forty values. Once the stability is determined, the reporting program will notify the user that the calorimeter has reached equilibrium. The Calorimeter Data Acquisition and Reporting Program operates continuously as described to monitor for calorimeter equilibrium and to generate a printable report with sample results.« less

  6. Performance of the ATLAS Tile Calorimeter

    NASA Astrophysics Data System (ADS)

    Heelan, Louise; ATLAS Collaboration

    2015-06-01

    The ATLAS Tile hadronic calorimeter (TileCal) provides highly-segmented energy measurements of incoming particles. It is a key detector for the measurement of hadrons, jets, tau leptons and missing transverse energy. It is also useful for identification and reconstruction of muons due to good signal to noise ratio. The calorimeter consists of thin steel plates and 460,000 scintillating tiles configured into 5000 cells, each viewed by two photomultipliers. The calorimeter response and its readout electronics is monitored to better than 1% using radioactive source, laser and charge injection systems. The calibration and performance of the calorimeter have been established through test beam measurements, cosmic ray muons and the large sample of proton-proton collisions acquired in 2011 and 2012. Results on the calorimeter performance are presented, including the absolute energy scale, timing, noise and associated stabilities. The results demonstrate that the Tile Calorimeter has performed well within the design requirements and it has given essential contribution to reconstructed objects and physics results. In addition, the data quality procedures used during the LHC data-taking are described and the outcome of the detector consolidation in the maintenance period is also presented.

  7. Calorimeter Control Program

    Energy Science and Technology Software Center (ESTSC)

    1998-11-03

    The Calorimeter Control Software provides PID (Proportional, Integral, and Derivative) Control for up to twelve Mound Calorimeters and five Calorimeter Waterbaths. The software accepts a Voltage input, compares it to a user defined setpoint, calculates a new voltage output designed to bring the input closer to the setpoint using a PID control algorithm, then sets the analog voltage output to the calculated value. The software is designed to interface with HP 3852A Data Acquisition Unitmore » via an HP-1B PC board. All field inputs are wired into Digital Input cards and field outputs are wired from Analog Output cards.« less

  8. Calorimeter Control Program

    SciTech Connect

    Plummer, Jean R.; Levi, Gerald

    1998-11-03

    The Calorimeter Control Software provides PID (Proportional, Integral, and Derivative) Control for up to twelve Mound Calorimeters and five Calorimeter Waterbaths. The software accepts a Voltage input, compares it to a user defined setpoint, calculates a new voltage output designed to bring the input closer to the setpoint using a PID control algorithm, then sets the analog voltage output to the calculated value. The software is designed to interface with HP 3852A Data Acquisition Unit via an HP-1B PC board. All field inputs are wired into Digital Input cards and field outputs are wired from Analog Output cards.

  9. CCP. Calorimeter Control Program

    SciTech Connect

    Plummer, J.; Levi, G.

    1998-10-01

    The Calorimeter Control Software provides PID (Proportional, Integral, and Derivative) Control for up to twelve Mound Calorimeters and five Calorimeter Waterbaths. The software accepts a Voltage input, compares it to a user defined setpoint, calculates a new voltage output designed to bring the input closer to the setpoint using a PID control algorithm, then sets the analog voltage output to the calculated value. The software is designed to interface with HP 3852A Data Acquisition Unit via an HP-1B PC board. All field inputs are wired into Digital Input cards and field outputs are wired from Analog Output cards.

  10. The LHCb DIRAC-based production and data management operations systems

    NASA Astrophysics Data System (ADS)

    Stagni, F.; Charpentier, P.; LHCb Collaboration

    2012-06-01

    The LHCb computing model was designed in order to support the LHCb physics program, taking into account LHCb specificities (event sizes, processing times etc...). Within this model several key activities are defined, the most important of which are real data processing (reconstruction, stripping and streaming, group and user analysis), Monte-Carlo simulation and data replication. In this contribution we detail how these activities are managed by the LHCbDIRAC Data Transformation System. The LHCbDIRAC Data Transformation System leverages the workload and data management capabilities provided by DIRAC, a generic community grid solution, to support data-driven workflows (or DAGs). The ability to combine workload and data tasks within a single DAG allows to create highly sophisticated workflows with the individual steps linked by the availability of data. This approach also provides the advantage of a single point at which all activities can be monitored and controlled. While several interfaces are currently supported (including python API and CLI), we will present the ability to create LHCb workflows through a secure web interface, control their state in addition to creating and submitting jobs. To highlight the versatility of the system we present in more detail experience with real data of the 2010 and 2011 LHC run.

  11. LHCb Upgrade: Scintillating Fibre Tracker

    NASA Astrophysics Data System (ADS)

    Tobin, Mark

    2016-07-01

    The LHCb detector will be upgraded during the Long Shutdown 2 (LS2) of the LHC in order to cope with higher instantaneous luminosities and to read out the data at 40 MHz using a trigger-less read-out system. All front-end electronics will be replaced and several sub-detectors must be redesigned to cope with higher occupancy. The current tracking detectors downstream of the LHCb dipole magnet will be replaced by the Scintillating Fibre (SciFi) Tracker. The SciFi Tracker will use scintillating fibres read out by Silicon Photomultipliers (SiPMs). State-of-the-art multi-channel SiPM arrays are being developed to read out the fibres and a custom ASIC will be used to digitise the signals from the SiPMs. The evolution of the design since the Technical Design Report in 2014 and the latest R & D results are presented.

  12. CMS electromagnetic calorimeter readout

    SciTech Connect

    Denes, P.; Wixted, R.

    1997-12-31

    The CMS Electromagnetic Calorimeter will consist of 109,008 crystals of Lead Tungstate (PbWO{sub 4}) arranged in a barrel (92880 crystals) and 2 endcaps (8064 crystals each). The crystals will be 25 radiation lengths long and cut in tapered shapes to make a hermetic calorimeter. The scintillation light from the crystals is captured by a photodetector, amplified and digitized. The properties of PbWO4, which is a new crystal still very much under development.

  13. Current status and performance of the BESIII electromagnetic calorimeter

    NASA Astrophysics Data System (ADS)

    Fang, Jian; Wang, Zhigang

    2012-12-01

    The design and construction of the BESIII electromagnetic calorimeter is introduced briefly. Radiation dose of CsI(Tl) crystals is monitored and history graph of integral dose of crystals is showed. LED-fiber system is used for monitoring the EMC light output, and large decrease of light output of several crystals is discussed. BESIII electromagnetic calorimeter works very well and its performance reach the design value.

  14. Temperature Effects in the ATIC BGO Calorimeter

    NASA Technical Reports Server (NTRS)

    Isbert, J.; Adams, J. H.; Ahn, H.; Bashindzhagyan, G.; Batkov, K.; Chang, J.; Christl, M. J.; Fazely, A.; Ganel, O.; Gunasigha, R.

    2006-01-01

    The Advanced Thin Ionization Calorimeter (ATIC) Balloon Experiment contains a segmented calorimeter composed of 320 individual BGO crystals (18 radiation lengths deep) to determine the particle energy. Like all inorganic scintillation crystals the light output of BGO depends not only on the energy deposited by particles but also on the temperature of the crystal. ATIC had successful flights in 2000/2001 and 2002/2003 from McMurdo, Antarctica. The temperature of balloon instruments varies during their flights at altitude due to sun angle variations and differences in albedo from the ground and is monitored and recorded. In order to determine the temperature sensitivity of the ATIC calorimeter it was temperature cycled in the thermal vacuum chamber at the CSBF in Palestine, TX. The temperature dependence is derived from the pulse height response to cosmic ray muons at various temperatures.

  15. Magnetically Coupled Calorimeters

    NASA Technical Reports Server (NTRS)

    Bandler, Simon

    2011-01-01

    Calorimeters that utilize the temperature sensitivity of magnetism have been under development for over 20 years. They have targeted a variety of different applications that require very high resolution spectroscopy. I will describe the properties of this sensor technology that distinguish it from other low temperature detectors and emphasize the types of application to which they appear best suited. I will review what has been learned so far about the best materials, geometries, and read-out amplifiers and our understanding of the measured performance and theoretical limits. I will introduce some of the applications where magnetic calorimeters are being used and also where they are in development for future experiments. So far, most magnetic calorimeter research has concentrated on the use of paramagnets to provide temperature sensitivity; recent studies have also focused on magnetically coupled calorimeters that utilize the diamagnetic response of superconductors. I will present some of the highlights of this research, and contrast the properties of the two magnetically coupled calorimeter types.

  16. The ALICE Electromagnetic Calorimeter

    SciTech Connect

    Gadrat, S.

    2010-06-01

    ALICE (A Large Ion Collider Experiment) is the only LHC experiment at CERN fully dedicated to the study of the quark and gluon plasma. Driven by the RHIC results on jet quenching, the ALICE collaboration has proposed to extend the capabilities of the ALICE detector for the study of high momentum photons and jets by adding a large acceptance calorimeter. This EMCal (ElectroMagnetic Calorimeter) is designed to provide an unbiased fast high-p{sub T} trigger and to measure the neutral energy of jets and photons up to 200 GeV. Four over ten supermodules of the calorimeter have been installed and commissioned at CERN in 2009 which represents 40% of the full acceptance.

  17. The ALICE Electromagnetic Calorimeter

    SciTech Connect

    Awes, Terry C; ALICE, Collaboration

    2010-05-01

    ALICE is the general purpose experiment at the LHC dedicated to the study of heavy-ion collisions. The electromagnetic calorimeter (EMCal) is a late addition to the ALICE suite of detectors with first modules installed in ALICE this year. The EMCal is designed to trigger on high energy gamma-rays and jets, and to enhance the capabilities of ALICE for these measurements. The EMCal is a Pb/scintillator sampling shish-kebab type calorimeter. The EMCal construction, readout, and performance in beam tests at the CERN SPS and PS are described.

  18. The ALICE Electromagnetic Calorimeter

    SciTech Connect

    Awes, Terry C; ALICE, Collaboration

    2010-01-01

    ALICE is the general purpose experiment at the LHC dedicated to the study of heavy-ion collisions. The electromagnetic calorimeter (EMCal) is a late addition to the ALICE suite of detectors with first modules installed in ALICE this year. The EMCal is designed to trigger on high energy gamma-rays and jets, and to enhance the capabilities of ALICE for these measurements. The EMCal is a Pb/scintillator sampling shish-kebab type calorimeter. The EMCal construction, readout, and performance in beam tests at the CERN SPS and PS are described.

  19. Dark photons from charm mesons at LHCb

    NASA Astrophysics Data System (ADS)

    Ilten, Philip; Thaler, Jesse; Williams, Mike; Xue, Wei

    2015-12-01

    We propose a search for dark photons A' at the LHCb experiment using the charm meson decay D*(2007 )0→D0A'. At nominal luminosity, D*0→D0γ decays will be produced at about 700 kHz within the LHCb acceptance, yielding over 5 trillion such decays during Run 3 of the LHC. Replacing the photon with a kinetically mixed dark photon, LHCb is then sensitive to dark photons that decay as A'→e+e-. We pursue two search strategies in this paper. The displaced strategy takes advantage of the large Lorentz boost of the dark photon and the excellent vertex resolution of LHCb, yielding a nearly background-free search when the A' decay vertex is significantly displaced from the proton-proton primary vertex. The resonant strategy takes advantage of the large event rate for D*0→D0A' and the excellent invariant-mass resolution of LHCb, yielding a background-limited search that nevertheless covers a significant portion of the A' parameter space. Both search strategies rely on the planned upgrade to a triggerless-readout system at LHCb in Run 3, which will permit the identification of low-momentum electron-positron pairs online during data taking. For dark photon masses below about 100 MeV, LHCb can explore nearly all of the dark photon parameter space between existing prompt-A' and beam-dump limits.

  20. An Inexpensive Solution Calorimeter

    ERIC Educational Resources Information Center

    Kavanagh, Emma; Mindel, Sam; Robertson, Giles; Hughes, D. E. Peter

    2008-01-01

    We describe the construction of a simple solution calorimeter, using a miniature bead thermistor as a temperature-sensing element. This has a response time of a few seconds and made it possible to carry out a thermometric reaction in under a minute, which led to minimal heat losses. Small temperature changes of 1 K associated with enthalpies of…

  1. The CMS Electromagnetic Calorimeter

    SciTech Connect

    Paramatti, Riccardo

    2005-10-12

    The electromagnetic calorimeter of the CMS experiment at LHC will consist of about 76000 Lead Tungstate crystals. Its main purpose is the very precise energy measurement of electrons and photons produced at 14 TeV centre-of-mass energy. A review of its performances and its construction status is given. Then the calibration strategy is described in details.

  2. Rare Decays at the LHCb Experiment

    NASA Astrophysics Data System (ADS)

    Pescatore, L.

    2015-06-01

    Rare decays of beauty and charm hadrons offer a rich playground to make precise tests of the Standard Model and look for New Physics at the level of quantum corrections. A review of recent LHCb results will be presented.

  3. The LHCb Silicon Tracker Project

    NASA Astrophysics Data System (ADS)

    Agari, M.; Bauer, C.; Baumeister, D.; Blouw, J.; Hofmann, W.; Knöpfle, K. T.; Löchner, S.; Schmelling, M.; Pugatch, V.; Bay, A.; Carron, B.; Frei, R.; Jiminez-Otero, S.; Tran, M.-T.; Voss, H.; Adeva, B.; Esperante, D.; Lois, C.; Vasquez, P.; Bernhard, R. P.; Bernet, R.; Ermoline, Y.; Gassner, J.; Köstner, S.; Lehner, F.; Needham, M.; Siegler, M.; Steinkamp, O.; Straumann, U.; Vollhardt, A.; Volyanskyy, D.

    2006-01-01

    Two silicon strip detectors, the Trigger Tracker(TT) and the Inner Tracker(IT) will be constructed for the LHCb experiment. Transverse momentum information extracted from the TT will be used in the Level 1 trigger. The IT is part of the main tracking system behind the magnet. Both silicon detectors will be read out using a custom-developed chip by the ASIC lab in Heidelberg. The signal-over-noise behavior and performance of various geometrical designs of the silicon sensors, in conjunction with the Beetle read-out chip, have been extensively studied in test beam experiments. Results from those experiments are presented, and have been used in the final choice of sensor geometry.

  4. Radionuclide calorimeter system

    DOEpatents

    Donohoue, Thomas P.; Oertel, Christopher P.; Tyree, William H.; Valdez, Joe L.

    1991-11-26

    A circuit for measuring temperature differentials in a calorimeter is disclosed. The temperature differential between the reference element and sample element containing a radioactive material is measured via a wheatstone bridge arrangement of thermistors. The bridge is driven with an alternating current on a pulsed basis to maintain the thermal floor of the calorimeter at a low reference value. A lock-in amplifier connected to the bridge phase locks a signal from the bridge to the input pulsed AC signal to provide a DC voltage. The DC voltage is sampled over time and provided to a digital computer. The digital computer, using curve fitting algorithms, will derive a function for the sample data. From the function, an equilibrium value for the temperature may be calculated.

  5. Radionuclide calorimeter system

    DOEpatents

    Donohoue, T.P.; Oertel, C.P.; Tyree, W.H.; Valdez, J.L.

    1991-11-26

    A circuit for measuring temperature differentials in a calorimeter is disclosed. The temperature differential between the reference element and sample element containing a radioactive material is measured via a Wheatstone bridge arrangement of thermistors. The bridge is driven with an alternating current on a pulsed basis to maintain the thermal floor of the calorimeter at a low reference value. A lock-in amplifier connected to the bridge phase locks a signal from the bridge to the input pulsed AC signal to provide a DC voltage. The DC voltage is sampled over time and provided to a digital computer. The digital computer, using curve fitting algorithms, will derive a function for the sample data. From the function, an equilibrium value for the temperature may be calculated. 7 figures.

  6. Modeling Complex Calorimeters

    NASA Technical Reports Server (NTRS)

    Figueroa-Feliciano, Enectali

    2004-01-01

    We have developed a software suite that models complex calorimeters in the time and frequency domain. These models can reproduce all measurements that we currently do in a lab setting, like IV curves, impedance measurements, noise measurements, and pulse generation. Since all these measurements are modeled from one set of parameters, we can fully describe a detector and characterize its behavior. This leads to a model than can be used effectively for engineering and design of detectors for particular applications.

  7. Precision closed bomb calorimeter for testing flame and gas producing initiators

    NASA Technical Reports Server (NTRS)

    Carpenter, D. R., Jr.; Taylor, A. C., Jr.

    1972-01-01

    A calorimeter has been developed under this study to help meet the needs of accurate performance monitoring of electrically or mechanically actuated flame and gas producing devices, such as squib-type initiators. A ten cubic centimeter closed bomb (closed volume) calorimeter was designed to provide a standard pressure trace and to measure a nominal 50 calorie output, using the basic components of a Parr Model 1411 calorimeter. Two prototype bombs were fabricated, pressure tested to 2600 psi, and extensively evaluated.

  8. Advanced Thin Ionization Calorimeter (ATIC)

    NASA Technical Reports Server (NTRS)

    Wefel, John P.

    1998-01-01

    This is the final report for NASA grant NAGW-4577, "Advanced Thin Ionization Calorimeter (ATIC)". This grant covered a joint project between LSU and the University of Maryland for a Concept Study of a new type of fully active calorimeter to be used to measure the energy spectra of very high energy cosmic rays, particularly Hydrogen and Helium, to beyond 1014 eV. This very high energy region has been studied with emulsion chamber techniques, but never investigated with electronic calorimeters. Technology had advanced to the point that a fully active calorimeter based upon Bismuth Germanate (BGO) scintillating crystals appeared feasible for balloon flight (and eventually space) experiments.

  9. Precision luminosity measurements at LHCb

    NASA Astrophysics Data System (ADS)

    The LHCb Collaboration

    2014-12-01

    Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy √s. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for √s = 2.76, 7 and 8 TeV (proton-proton collisions) and for √sNN = 5 TeV (proton-lead collisions). Both the "van der Meer scan" and "beam-gas imaging" luminosity calibration methods were employed. It is observed that the beam density profile cannot always be described by a function that is factorizable in the two transverse coordinates. The introduction of a two-dimensional description of the beams improves significantly the consistency of the results. For proton-proton interactions at √s = 8 TeV a relative precision of the luminosity calibration of 1.47% is obtained using van der Meer scans and 1.43% using beam-gas imaging, resulting in a combined precision of 1.12%. Applying the calibration to the full data set determines the luminosity with a precision of 1.16%. This represents the most precise luminosity measurement achieved so far at a bunched-beam hadron collider.

  10. Scintillating fiber ribbon --- tungsten calorimeter

    SciTech Connect

    Bross, A.; Crisler, M.; Kross, B.; Wrbanek, J.

    1989-07-14

    We describe an ultra-high density scintillating fiber and tungsten calorimeter used as an active beam-dump for electrons. Data showing the calorimeter response to electrons with momenta between 50 and 350 GeV/c are presented. 9 figs.

  11. Improvements in a calorimeter for high-power CW lasers

    NASA Technical Reports Server (NTRS)

    Chamberlain, G. E.; Simpson, P. A.; Smith, R. L.

    1978-01-01

    A technique for improving the measurement certainty with the BB series (Smith et al., 1972) of electrically calibrated calorimeters used in high-energy lasers is described. The technique is based on monitoring the energy which is backscattered from the meter and monitoring the overspill radiation impinging on the calorimeter at the entrance aperture. The design and performance of a second generation BB meter is discussed and compared to that of the original device in terms of number of electrical calibrations, the residual standard deviation of electrical calibration, the calibration constant for laser energy, the correcting factor for systematics, inaccuracy, imprecision, and uncertainty.

  12. Proposed Inclusive Dark Photon Search at LHCb

    NASA Astrophysics Data System (ADS)

    Ilten, Philip; Soreq, Yotam; Thaler, Jesse; Williams, Mike; Xue, Wei

    2016-06-01

    We propose an inclusive search for dark photons A' at the LHCb experiment based on both prompt and displaced dimuon resonances. Because the couplings of the dark photon are inherited from the photon via kinetic mixing, the dark photon A'→μ+μ- rate can be directly inferred from the off-shell photon γ*→μ+μ- rate, making this a fully data-driven search. For run 3 of the LHC, we estimate that LHCb will have sensitivity to large regions of the unexplored dark-photon parameter space, especially in the 210-520 MeV and 10-40 GeV mass ranges. This search leverages the excellent invariant-mass and vertex resolution of LHCb, along with its unique particle-identification and real-time data-analysis capabilities.

  13. Implications of LHCb measurements and future prospects

    NASA Astrophysics Data System (ADS)

    Bharucha, A.; Bigi, I. I.; Bobeth, C.; Bobrowski, M.; Brod, J.; Buras, A. J.; Davies, C. T. H.; Datta, A.; Delaunay, C.; Descotes-Genon, S.; Ellis, J.; Feldmann, T.; Fleischer, R.; Gedalia, O.; Girrbach, J.; Guadagnoli, D.; Hiller, G.; Hochberg, Y.; Hurth, T.; Isidori, G.; Jäger, S.; Jung, M.; Kagan, A.; Kamenik, J. F.; Lenz, A.; Ligeti, Z.; London, D.; Mahmoudi, F.; Matias, J.; Nandi, S.; Nir, Y.; Paradisi, P.; Perez, G.; Petrov, A. A.; Rattazzi, R.; Sharpe, S. R.; Silvestrini, L.; Soni, A.; Straub, D. M.; van Dyk, D.; Virto, J.; Wang, Y.-M.; Weiler, A.; Zupan, J.; Aaij, R.; Abellan Beteta, C.; Adametz, A.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Anelli, M.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Bachmann, S.; Back, J. J.; Baesso, C.; Baldini, W.; Band, H.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bates, A.; Bauer, Th.; Bay, A.; Beddow, J.; Bediaga, I.; Beigbeder-Beau, C.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Benayoun, M.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernard, F.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; van Beveren, V.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blanks, C.; Blouw, J.; Blusk, S.; Bobrov, A.; Bocci, V.; Bochin, B.; Boer Rookhuizen, H.; Bogdanova, G.; Bonaccorsi, E.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Brarda, L.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Büchler-Germann, A.; Burducea, I.; Bursche, A.; Buytaert, J.; Cacérès, T.; Cachemiche, J.-P.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casajus Ramo, A.; Casse, G.; Cattaneo, M.; Cauet, Ch.; Ceelie, L.; Chadaj, B.; Chanal, H.; Charles, M.; Charlet, D.; Charpentier, Ph.; Chebbi, M.; Chen, P.; Chiapolini, N.; Chrzaszcz, M.; Ciambrone, P.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Corajod, B.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; D'Antone, I.; David, P.; David, P. N. Y.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Groen, P.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Decreuse, G.; Degaudenzi, H.; Del Buono, L.; Deplano, C.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dickens, J.; Dijkstra, H.; Diniz Batista, P.; Dogaru, M.; Domingo Bonal, F.; Domke, M.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Drancourt, C.; Duarte, O.; Dumps, R.; Dupertuis, F.; Duval, P.-Y.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisenhardt, S.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Elsby, D.; Evangelisti, F.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Faulkner, P. J. W.; Fave, V.; Felici, G.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fitzpatrick, C.; Föhr, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Fournier, C.; Francisco, O.; Frank, M.; Frei, C.; Frei, R.; Frosini, M.; Fuchs, H.; Furcas, S.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Gets, S.; Ghez, Ph.; Giachero, A.; Gibson, V.; Gligorov, V. V.; Göbel, C.; Golovtsov, V.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gong, G.; Gong, H.; Gordon, H.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Gromov, V.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Guzik, Z.; Gys, T.; Hachon, F.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Harrison, P. F.; Hartmann, T.; He, J.; van der Heijden, B.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Hicks, E.; Hill, D.; Hoballah, M.; Hofmann, W.; Hombach, C.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Ilten, P.; Imong, J.; Jacobsson, R.; Jaeger, A.; Jamet, O.; Jans, E.; Jansen, F.; Jansen, L.; Jansweijer, P.; Jaton, P.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Jost, B.; Kaballo, M.; Kandybei, S.; Karacson, M.; Karavichev, O.; Karbach, T. M.; Kashchuk, A.; Kechadi, T.; Kenyon, I. R.; Kerzel, U.; Ketel, T.; Keune, A.; Khanji, B.; Kihm, T.; Kluit, R.; Kochebina, O.; Komarov, V.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kos, J.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Kristic, R.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudenko, Y.; Kudryavtsev, V.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Landi, L.; Lanfranchi, G.; Langenbruch, C.; Laptev, S.; Latham, T.; Lax, I.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Li, Y.; Li Gioi, L.; Likhoded, A.; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; von Loeben, J.; Lopes, J. H.; Lopez Asamar, E.; Lopez-March, N.; Lu, H.; Luisier, J.; Luo, H.; Mac Raighne, A.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Maino, M.; Malde, S.; Manca, G.; Mancinelli, G.; Mangiafave, N.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martín Sánchez, A.; Martinelli, M.; Martinez Santos, D.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Matveev, M.; Maurice, E.; Mauricio, J.; Mazurov, A.; McCarthy, J.; McNulty, R.; Meadows, B.; Meissner, M.; Mejia, H.; Mendez-Munoz, V.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Molina Rodriguez, J.; Monteil, S.; Moran, D.; Morawski, P.; Mountain, R.; Mous, I.; Muheim, F.; Mul, F.; Müller, K.; Munneke, B.; Muresan, R.; Muryn, B.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Nawrot, A.; Needham, M.; Neufeld, N.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Nikitin, N.; Nikodem, T.; Nikolaiko, Y.; Nisar, S.; Nomerotski, A.; Novoselov, A.; Oblakowska-Mucha, A.; Obraztsov, V.; Oggero, S.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Orlandea, M.; Ostankov, A.; Otalora Goicochea, J. M.; van Overbeek, M.; Owen, P.; Pal, B. K.; Palano, A.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrick, G. N.; Patrignani, C.; Pavel-Nicorescu, C.; Pazos Alvarez, A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perego, D. L.; Perez Trigo, E.; Pérez-Calero Yzquierdo, A.; Perret, P.; Perrin-Terrin, M.; Pessina, G.; Petridis, K.; Petrolini, A.; van Petten, O.; Phan, A.; Picatoste Olloqui, E.; Piedigrossi, D.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Playfer, S.; Plo Casasus, M.; Polci, F.; Polok, G.; Poluektov, A.; Polycarpo, E.; Popov, D.; Popovici, B.; Potterat, C.; Powell, A.; Prisciandaro, J.; Pugatch, M.; Pugatch, V.; Puig Navarro, A.; Qian, W.; Rademacker, J. H.; Rakotomiaramanana, B.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redford, S.; Reid, M. M.; dos Reis, A. C.; Rethore, F.; Ricciardi, S.; Richards, A.; Rinnert, K.; Rives Molina, V.; Roa Romero, D. A.; Robbe, P.; Rodrigues, E.; Rodriguez Perez, P.; Roeland, E.; Rogers, G. J.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; de Roo, K.; Rouvinet, J.; Roy, L.; Rudloff, K.; Ruf, T.; Ruiz, H.; Sabatino, G.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salzmann, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Saornil Gamarra, S.; Sapunov, M.; Saputi, A.; Sarti, A.; Satriano, C.; Satta, A.; Savidge, T.; Savrie, M.; Schaack, P.; Schiller, M.; Schimmel, A.; Schindler, H.; Schleich, S.; Schlupp, M.; Schmelling, M.; Schmidt, B.; Schneider, O.; Schneider, T.; Schopper, A.; Schuijlenburg, H.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Seco, M.; Semennikov, A.; Senderowska, K.; Sepp, I.; Serra, N.; Serrano, J.; Seyfert, P.; Shao, B.; Shapkin, M.; Shapoval, I.; Shatalov, P.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Sigurdsson, S.; Silva Coutinho, R.; Skwarnicki, T.; Slater, M. W.; Sluijk, T.; Smith, N. A.; Smith, E.; Smith, M.; Sobczak, K.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Sparkes, A.; Spradlin, P.; Squerzanti, S.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stenyakin, O.; Stoica, S.; Stone, S.; Storaci, B.; Straticiuc, M.; Straumann, U.; Subbiah, V. K.; Swientek, S.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Teodorescu, E.; Teubert, F.; Thomas, C.; Thomas, E.; Tikhonov, A.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Tocut, V.; Tolk, S.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, M. T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ubeda Garcia, M.; Ukleja, A.; Ullaland, O.; Urner, D.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vink, W.; Volkov, S.; Volkov, V.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; Vouters, G.; Waldi, R.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D. R.; Warda, K.; Watson, N. K.; Webber, A. D.; Websdale, D.; Wenerke, P.; Whitehead, M.; Wicht, J.; Wiedner, D.; Wiggers, L.; Wilkinson, G.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wishahi, J.; Witek, M.; Witzeling, W.; Wotton, S. A.; Wright, S.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Xue, T.; Yang, Z.; Young, R.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zappon, F.; Zavertyaev, M.; Zeng, M.; Zhang, F.; Zhang, L.; Zhang, W. C.; Zhang, Y.; Zhelezov, A.; Zhong, L.; Zverev, E.; Zvyagin, A.; Zwart, A.

    2013-04-01

    During 2011 the LHCb experiment at CERN collected 1.0 fb-1 of √{s} = 7 TeV pp collisions. Due to the large heavy quark production cross-sections, these data provide unprecedented samples of heavy flavoured hadrons. The first results from LHCb have made a significant impact on the flavour physics landscape and have definitively proved the concept of a dedicated experiment in the forward region at a hadron collider. This document discusses the implications of these first measurements on classes of extensions to the Standard Model, bearing in mind the interplay with the results of searches for on-shell production of new particles at ATLAS and CMS. The physics potential of an upgrade to the LHCb detector, which would allow an order of magnitude more data to be collected, is emphasised.

  14. The LHCb trigger and its upgrade

    NASA Astrophysics Data System (ADS)

    Dziurda, A.

    2016-07-01

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

  15. LHCb Physics and 2010-11 prospects

    SciTech Connect

    Perazzini, Stefano

    2011-10-24

    LHCb is one of the four major experiments operating at the Large Hadron Collider, and is specifically dedicated to the measurement of CP-violation and rare decays in the beauty and charm quark sectors. By employing data from early LHC runs it is possible to assess the performance of the detector and to better understand the potential of the LHCb flavour programme. After a brief introduction of the motivations and of the relevant physics goals, the prospects about key CP-violation and rare decay measurements will be presented. Emphasis will be given to those topics where results with particular sensitivity to New Physics are expected during the 2010-11 run.

  16. LHCb Physics and 2010-11 prospects

    NASA Astrophysics Data System (ADS)

    Perazzini, Stefano

    2011-10-01

    LHCb is one of the four major experiments operating at the Large Hadron Collider, and is specifically dedicated to the measurement of CP-violation and rare decays in the beauty and charm quark sectors. By employing data from early LHC runs it is possible to assess the performance of the detector and to better understand the potential of the LHCb flavour programme. After a brief introduction of the motivations and of the relevant physics goals, the prospects about key CP-violation and rare decay measurements will be presented. Emphasis will be given to those topics where results with particular sensitivity to New Physics are expected during the 2010-11 run.

  17. A New Nightly Build System for LHCb

    NASA Astrophysics Data System (ADS)

    Clemencic, M.; Couturier, B.

    2014-06-01

    The nightly build system used so far by LHCb has been implemented as an extension of the system developed by CERN PH/SFT group (as presented at CHEP2010). Although this version has been working for many years, it has several limitations in terms of extensibility, management and ease of use, so that it was decided to develop a new version based on a continuous integration system. In this paper we describe a new implementation of the LHCb Nightly Build System based on the open source continuous integration system Jenkins and report on the experience of configuring a complex build workflow in Jenkins.

  18. Time Structure Analysis of the LHCb DAQ Network

    NASA Astrophysics Data System (ADS)

    Antichi, G.; Bruyere, M.; Cámpora Pérez, D. H.; Liu, G.; Neufeld, N.; Giordano, S.; Owezarski, P.; Moore, A. W.

    2014-06-01

    The LHCb DAQ Network is a real time high performance network, in which 350 data sources send data over a Gigabit Ethernet LAN to more than 1500 receiving nodes. The aggregated throughput of the application, called Event Building, is more than 60 Gbps. The protocol employed by LHCb makes the sending nodes transmit simultaneously portions of events to one receiving node at a time, which is selected using a credit-token scheme. The resulting traffic is very bursty and sensitive to irregularities in the temporal distribution of packet-bursts to the same destination or region of the network. In order to study the relevant properties of such a dataflow, a non-disruptive monitoring setup based on a networking capable FPGA (Netfpga) has been deployed. The Netfpga allows order of hundred nano-second precise time-stamping of packets. We study in detail the timing structure of the Event Building communication, and we identify potential effects of micro-bursts like buffer packet drops or jitter.

  19. LHCb experience with running jobs in virtual machines

    NASA Astrophysics Data System (ADS)

    McNab, A.; Stagni, F.; Luzzi, C.

    2015-12-01

    The LHCb experiment has been running production jobs in virtual machines since 2013 as part of its DIRAC-based infrastructure. We describe the architecture of these virtual machines and the steps taken to replicate the WLCG worker node environment expected by user and production jobs. This relies on the uCernVM system for providing root images for virtual machines. We use the CernVM-FS distributed filesystem to supply the root partition files, the LHCb software stack, and the bootstrapping scripts necessary to configure the virtual machines for us. Using this approach, we have been able to minimise the amount of contextualisation which must be provided by the virtual machine managers. We explain the process by which the virtual machine is able to receive payload jobs submitted to DIRAC by users and production managers, and how this differs from payloads executed within conventional DIRAC pilot jobs on batch queue based sites. We describe our operational experiences in running production on VM based sites managed using Vcycle/OpenStack, Vac, and HTCondor Vacuum. Finally we show how our use of these resources is monitored using Ganglia and DIRAC.

  20. Installation and operation of recording calorimeters

    SciTech Connect

    Kersey, A.F.

    1984-04-01

    The Cutler-Hammer recording calorimeter is illustrated in this paper. This calorimeter measures the total calorific value of combustible gas, and continuously samples, indicates, and records BTU per cubic foot. The paper emphasizes the importance of calorimeter accuracy. It is suggested that the calorimeter manufacturer be consulted for advice and assistance in developing a sound service program for trouble shooting and for service.

  1. The ATLAS tile calorimeter performance at the LHC

    SciTech Connect

    Calkins, R.

    2011-07-01

    The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, is a key detector component to detect hadrons, jets and taus and to measure the missing transverse energy. Due to the very good muon signal to noise ratio it assists the spectrometer in the identification and reconstruction of muons. TileCal is built of steel and scintillating tiles coupled to optical fibers and read out by photomultipliers. The calorimeter is equipped with systems that allow to monitor and to calibrate each stage of the read out system exploiting different signal sources: laser light, charge injection and a radioactive source. The performance of the calorimeter has been measured and monitored using calibration data, random triggered data, cosmic muons and more importantly LHC collision events. The results presented here assess the absolute energy scale calibration precision, the energy and timing uniformity and the synchronization precision. The ensemble of the results demonstrates a very good understanding of the performance of the Tile Calorimeter that is proved to be well within the design expectations. (authors)

  2. The LHCb Detector at the LHC

    NASA Astrophysics Data System (ADS)

    LHCb Collaboration; Alves, A. Augusto, Jr.; Filho, L. M. Andrade; Barbosa, A. F.; Bediaga, I.; Cernicchiaro, G.; Guerrer, G.; Lima, H. P., Jr.; Machado, A. A.; Magnin, J.; Marujo, F.; de Miranda, J. M.; Reis, A.; Santos, A.; Toledo, A.; Akiba, K.; Amato, S.; de Paula, B.; de Paula, L.; da Silva, T.; Gandelman, M.; Lopes, J. H.; Maréchal, B.; Moraes, D.; Polycarpo, E.; Rodrigues, F.; Ballansat, J.; Bastian, Y.; Boget, D.; DeBonis, I.; Coco, V.; David, P. Y.; Decamp, D.; Delebecque, P.; Drancourt, C.; Dumont-Dayot, N.; Girard, C.; Lieunard, B.; Minard, M. N.; Pietrzyk, B.; Rambure, T.; Rospabe, G.; T'Jampens, S.; Ajaltouni, Z.; Bohner, G.; Bonnefoy, R.; Borras, D.; Carloganu, C.; Chanal, H.; Conte, E.; Cornat, R.; Crouau, M.; Delage, E.; Deschamps, O.; Henrard, P.; Jacquet, P.; Lacan, C.; Laubser, J.; Lecoq, J.; Lefèvre, R.; Magne, M.; Martemiyanov, M.; Mercier, M.-L.; Monteil, S.; Niess, V.; Perret, P.; Reinmuth, G.; Robert, A.; Suchorski, S.; Arnaud, K.; Aslanides, E.; Babel, J.; Benchouk, C.; Cachemiche, J.-P.; Cogan, J.; Derue, F.; Dinkespiler, B.; Duval, P.-Y.; Garonne, V.; Favard, S.; LeGac, R.; Leon, F.; Leroy, O.; Liotard, P.-L.; Marin, F.; Menouni, M.; Ollive, P.; Poss, S.; Roche, A.; Sapunov, M.; Tocco, L.; Viaud, B.; Tsaregorodtsev, A.; Amhis, Y.; Barrand, G.; Barsuk, S.; Beigbeder, C.; Beneyton, R.; Breton, D.; Callot, O.; Charlet, D.; D'Almagne, B.; Duarte, O.; Fulda-Quenzer, F.; Jacholkowska, A.; Jean-Marie, B.; Lefrancois, J.; Machefert, F.; Robbe, P.; Schune, M.-H.; Tocut, V.; Videau, I.; Benayoun, M.; David, P.; DelBuono, L.; Gilles, G.; Domke, M.; Futterschneider, H.; Ilgner, Ch; Kapusta, P.; Kolander, M.; Krause, R.; Lieng, M.; Nedos, M.; Rudloff, K.; Schleich, S.; Schwierz, R.; Spaan, B.; Wacker, K.; Warda, K.; Agari, M.; Bauer, C.; Baumeister, D.; Bulian, N.; Fuchs, H. P.; Fallot-Burghardt, W.; Glebe, T.; Hofmann, W.; Knöpfle, K. T.; Löchner, S.; Ludwig, A.; Maciuc, F.; Sanchez Nieto, F.; Schmelling, M.; Schwingenheuer, B.; Sexauer, E.; Smale, N. J.; Trunk, U.; Voss, H.; Albrecht, J.; Bachmann, S.; Blouw, J.; Deissenroth, M.; Deppe, H.; Dreis, H. B.; Eisele, F.; Haas, T.; Hansmann-Menzemer, S.; Hennenberger, S.; Knopf, J.; Moch, M.; Perieanu, A.; Rabenecker, S.; Rausch, A.; Rummel, C.; Rusnyak, R.; Schiller, M.; Stange, U.; Uwer, U.; Walter, M.; Ziegler, R.; Avoni, G.; Balbi, G.; Bonifazi, F.; Bortolotti, D.; Carbone, A.; D'Antone, I.; Galli, D.; Gregori, D.; Lax, I.; Marconi, U.; Peco, G.; Vagnoni, V.; Valenti, G.; Vecchi, S.; Bonivento, W.; Cardini, A.; Cadeddu, S.; DeLeo, V.; Deplano, C.; Furcas, S.; Lai, A.; Oldeman, R.; Raspino, D.; Saitta, B.; Serra, N.; Baldini, W.; Brusa, S.; Chiozzi, S.; Cotta Ramusino, A.; Evangelisti, F.; Franconieri, A.; Germani, S.; Gianoli, A.; Guoming, L.; Landi, L.; Malaguti, R.; Padoan, C.; Pennini, C.; Savriè, M.; Squerzanti, S.; Zhao, T.; Zhu, M.; Bizzeti, A.; Graziani, G.; Lenti, M.; Lenzi, M.; Maletta, F.; Pennazzi, S.; Passaleva, G.; Veltri, M.; Alfonsi, M.; Anelli, M.; Balla, A.; Battisti, A.; Bencivenni, G.; Campana, P.; Carletti, M.; Ciambrone, P.; Corradi, G.; Dané, E.; Di Virgilio, A.; DeSimone, P.; Felici, G.; Forti, C.; Gatta, M.; Lanfranchi, G.; Murtas, F.; Pistilli, M.; Poli Lener, M.; Rosellini, R.; Santoni, M.; Saputi, A.; Sarti, A.; Sciubba, A.; Zossi, A.; Ameri, M.; Cuneo, S.; Fontanelli, F.; Gracco, V.; Miní, G.; Parodi, M.; Petrolini, A.; Sannino, M.; Vinci, A.; Alemi, M.; Arnaboldi, C.; Bellunato, T.; Calvi, M.; Chignoli, F.; DeLucia, A.; Galotta, G.; Mazza, R.; Matteuzzi, C.; Musy, M.; Negri, P.; Perego, D.; Pessina, G.; Auriemma, G.; Bocci, V.; Buccheri, A.; Chiodi, G.; Di Marco, S.; Iacoangeli, F.; Martellotti, G.; Nobrega, R.; Pelosi, A.; Penso, G.; Pinci, D.; Rinaldi, W.; Rossi, A.; Santacesaria, R.; Satriano, C.; Carboni, G.; Iannilli, M.; Massafferri Rodrigues, A.; Messi, R.; Paoluzzi, G.; Sabatino, G.; Santovetti, E.; Satta, A.; Amoraal, J.; van Apeldoorn, G.; Arink, R.; van Bakel, N.; Band, H.; Bauer, Th; Berkien, A.; van Beuzekom, M.; Bos, E.; Bron, Ch; Ceelie, L.; Doets, M.; van der Eijk, R.; Fransen, J.-P.; de Groen, P.; Gromov, V.; Hierck, R.; Homma, J.; Hommels, B.; Hoogland, W.; Jans, E.; Jansen, F.; Jansen, L.; Jaspers, M.; Kaan, B.; Koene, B.; Koopstra, J.; Kroes, F.; Kraan, M.; Langedijk, J.; Merk, M.; Mos, S.; Munneke, B.; Palacios, J.; Papadelis, A.; Pellegrino, A.; van Petten, O.; du Pree, T.; Roeland, E.; Ruckstuhl, W.; Schimmel, A.; Schuijlenburg, H.; Sluijk, T.; Spelt, J.; Stolte, J.; Terrier, H.; Tuning, N.; Van Lysebetten, A.; Vankov, P.; Verkooijen, J.; Verlaat, B.; Vink, W.; de Vries, H.; Wiggers, L.; Ybeles Smit, G.; Zaitsev, N.; Zupan, M.; Zwart, A.; van den Brand, J.; Bulten, H. J.; de Jong, M.; Ketel, T.; Klous, S.; Kos, J.; M'charek, B.; Mul, F.; Raven, G.; Simioni, E.; Cheng, J.; Dai, G.; Deng, Z.; Gao, Y.; Gong, G.; Gong, H.; He, J.; Hou, L.; Li, J.; Qian, W.; Shao, B.; Xue, T.; Yang, Z.; Zeng, M.; Muryn, B.; Ciba, K.; Oblakowska-Mucha, A.; Blocki, J.; Galuszka, K.; Hajduk, L.; Michalowski, J.; Natkaniec, Z.; Polok, G.; Stodulski, M.; Witek, M.; Brzozowski, K.; Chlopik, A.; Gawor, P.; Guzik, Z.; Nawrot, A.; Srednicki, A.; Syryczynski, K.; Szczekowski, M.; Anghel, D. V.; Cimpean, A.; Coca, C.; Constantin, F.; Cristian, P.; Dumitru, D. D.; Dumitru, D. T.; Giolu, G.; Kusko, C.; Magureanu, C.; Mihon, Gh; Orlandea, M.; Pavel, C.; Petrescu, R.; Popescu, S.; Preda, T.; Rosca, A.; Rusu, V. L.; Stoica, R.; Stoica, S.; Tarta, P. D.; Filippov, S.; Gavrilov, Yu; Golyshkin, L.; Gushchin, E.; Karavichev, O.; Klubakov, V.; Kravchuk, L.; Kutuzov, V.; Laptev, S.; Popov, S.; Aref'ev, A.; Bobchenko, B.; Dolgoshein, V.; Egorychev, V.; Golutvin, A.; Gushchin, O.; Konoplyannikov, A.; Korolko, I.; Kvaratskheliya, T.; Machikhiliyan, I.; Malyshev, S.; Mayatskaya, E.; Prokudin, M.; Rusinov, D.; Rusinov, V.; Shatalov, P.; Shchutska, L.; Tarkovskiy, E.; Tayduganov, A.; Voronchev, K.; Zhiryakova, O.; Bobrov, A.; Bondar, A.; Eidelman, S.; Kozlinsky, A.; Shekhtman, L.; Beloous, K. S.; Dzhelyadin, R. I.; Gelitsky, Yu V.; Gouz, Yu P.; Kachnov, K. G.; Kobelev, A. S.; Matveev, V. D.; Novikov, V. P.; Obraztsov, V. F.; Ostankov, A. P.; Romanovsky, V. I.; Rykalin, V. I.; Soldatov, A. P.; Soldatov, M. M.; Tchernov, E. N.; Yushchenko, O. P.; Bochin, B.; Bondar, N.; Fedorov, O.; Golovtsov, V.; Guets, S.; Kashchuk, A.; Lazarev, V.; Maev, O.; Neustroev, P.; Sagidova, N.; Spiridenkov, E.; Volkov, S.; Vorobyev, An; Vorobyov, A.; Aguilo, E.; Bota, S.; Calvo, M.; Comerma, A.; Cano, X.; Dieguez, A.; Herms, A.; Lopez, E.; Luengo, S.; Garra, J.; Garrido, Ll; Gascon, D.; Gaspar de Valenzuela, A.; Gonzalez, C.; Graciani, R.; Grauges, E.; Perez Calero, A.; Picatoste, E.; Riera, J.; Rosello, M.; Ruiz, H.; Vilasis, X.; Xirgu, X.; Adeva, B.; Cid Vidal, X.; MartÉnez Santos, D.; Esperante Pereira, D.; Fungueiriño Pazos, J. L.; Gallas Torreira, A.; Gómez, C. Lois; Pazos Alvarez, A.; Pérez Trigo, E.; Pló Casasús, M.; Rodriguez Cobo, C.; Rodríguez Pérez, P.; Saborido, J. J.; Seco, M.; Vazquez Regueiro, P.; Bartalini, P.; Bay, A.; Bettler, M.-O.; Blanc, F.; Borel, J.; Carron, B.; Currat, C.; Conti, G.; Dormond, O.; Ermoline, Y.; Fauland, P.; Fernandez, L.; Frei, R.; Gagliardi, G.; Gueissaz, N.; Haefeli, G.; Hicheur, A.; Jacoby, C.; Jalocha, P.; Jimenez-Otero, S.; Hertig, J.-P.; Knecht, M.; Legger, F.; Locatelli, L.; Moser, J.-R.; Needham, M.; Nicolas, L.; Perrin-Giacomin, A.; Perroud, J.-P.; Potterat, C.; Ronga, F.; Schneider, O.; Schietinger, T.; Steele, D.; Studer, L.; Tareb, M.; Tran, M. T.; van Hunen, J.; Vervink, K.; Villa, S.; Zwahlen, N.; Bernet, R.; Büchler, A.; Gassner, J.; Lehner, F.; Sakhelashvili, T.; Salzmann, C.; Sievers, P.; Steiner, S.; Steinkamp, O.; Straumann, U.; van Tilburg, J.; Vollhardt, A.; Volyanskyy, D.; Ziegler, M.; Dovbnya, A.; Ranyuk, Yu; Shapoval, I.; Borisova, M.; Iakovenko, V.; Kyva, V.; Kovalchuk, O.; Okhrimenko, O.; Pugatch, V.; Pylypchenko, Yu; Adinolfi, M.; Brook, N. H.; Head, R. D.; Imong, J. P.; Lessnoff, K. A.; Metlica, F. C. D.; Muir, A. J.; Rademacker, J. H.; Solomin, A.; Szczypka, P. M.; Barham, C.; Buszello, C.; Dickens, J.; Gibson, V.; Haines, S.; Harrison, K.; Jones, C. R.; Katvars, S.; Kerzel, U.; Lazzeroni, C.; Li, Y. Y.; Rogers, G.; Storey, J.; Skottowe, H.; Wotton, S. A.; Adye, T. J.; Densham, C. J.; Easo, S.; Franek, B.; Loveridge, P.; Morrow, D.; Morris, J. V.; Nandakumar, R.; Nardulli, J.; Papanestis, A.; Patrick, G. N.; Ricciardi, S.; Woodward, M. L.; Zhang, Z.; Chamonal, R. J. U.; Clark, P. J.; Clarke, P.; Eisenhardt, S.; Gilardi, N.; Khan, A.; Kim, Y. M.; Lambert, R.; Lawrence, J.; Main, A.; McCarron, J.; Mclean, C.; Muheim, F.; Osorio-Oliveros, A. F.; Playfer, S.; Styles, N.; Xie, Y.; Bates, A.; Carson, L.; da Cunha Marinho, F.; Doherty, F.; Eklund, L.; Gersabeck, M.; Haddad, L.; Macgregor, A. A.; Melone, J.; McEwan, F.; Petrie, D. M.; Paterson, S. K.; Parkes, C.; Pickford, A.; Rakotomiaramanana, B.; Rodrigues, E.; Saavedra, A. F.; Soler, F. J. P.; Szumlak, T.; Viret, S.; Allebone, L.; Awunor, O.; Back, J.; Barber, G.; Barnes, C.; Cameron, B.; Clark, D.; Clark, I.; Dornan, P.; Duane, A.; Eames, C.; Egede, U.; Girone, M.; Greenwood, S.; Hallam, R.; Hare, R.; Howard, A.; Jolly, S.; Kasey, V.; Khaleeq, M.; Koppenburg, P.; Miller, D.; Plackett, R.; Price, D.; Reece, W.; Savage, P.; Savidge, T.; Simmons, B.; Vidal-Sitjes, G.; Websdale, D.; Affolder, A.; Anderson, J. S.; Biagi, S. F.; Bowcock, T. J. V.; Carroll, J. L.; Casse, G.; Cooke, P.; Donleavy, S.; Dwyer, L.; Hennessy, K.; Huse, T.; Hutchcroft, D.; Jones, D.; Lockwood, M.; McCubbin, M.; McNulty, R.; Muskett, D.; Noor, A.; Patel, G. D.; Rinnert, K.; Shears, T.; Smith, N. A.; Southern, G.; Stavitski, I.; Sutcliffe, P.; Tobin, M.; Traynor, S. M.; Turner, P.; Whitley, M.; Wormald, M.; Wright, V.; Bibby, J. H.; Brisbane, S.; Brock, M.; Charles, M.; Cioffi, C.; Gligorov, V. V.; Handford, T.; Harnew, N.; Harris, F.; John, M. J. J.; Jones, M.; Libby, J.; Martin, L.; McArthur, I. A.; Muresan, R.; Newby, C.; Ottewell, B.; Powell, A.; Rotolo, N.; Senanayake, R. S.; Somerville, L.; Soroko, A.; Spradlin, P.; Sullivan, P.; Stokes-Rees, I.; Topp-Jorgensen, S.; Xing, F.; Wilkinson, G.; Artuso, M.; Belyaev, I.; Blusk, S.; Lefeuvre, G.; Menaa, N.; Menaa-Sia, R.; Mountain, R.; Skwarnicki, T.; Stone, S.; Wang, J. C.; Abadie, L.; Aglieri-Rinella, G.; Albrecht, E.; André, J.; Anelli, G.; Arnaud, N.; Augustinus, A.; Bal, F.; Barandela Pazos, M. C.; Barczyk, A.; Bargiotti, M.; Batista Lopes, J.; Behrendt, O.; Berni, S.; Binko, P.; Bobillier, V.; Braem, A.; Brarda, L.; Buytaert, J.; Camilleri, L.; Cambpell, M.; Castellani, G.; Cataneo, F.; Cattaneo, M.; Chadaj, B.; Charpentier, P.; Cherukuwada, S.; Chesi, E.; Christiansen, J.; Chytracek, R.; Clemencic, M.; Closier, J.; Collins, P.; Colrain, P.; Cooke, O.; Corajod, B.; Corti, G.; D'Ambrosio, C.; Damodaran, B.; David, C.; de Capua, S.; Decreuse, G.; Degaudenzi, H.; Dijkstra, H.; Droulez, J.-P.; Duarte Ramos, D.; Dufey, J. P.; Dumps, R.; Eckstein, D.; Ferro-Luzzi, M.; Fiedler, F.; Filthaut, F.; Flegel, W.; Forty, R.; Fournier, C.; Frank, M.; Frei, C.; Gaidioz, B.; Gaspar, C.; Gayde, J.-C.; Gavillet, P.; Go, A.; Gracia Abril, G.; Graulich, J.-S.; Giudici, P.-A.; Guirao Elias, A.; Guglielmini, P.; Gys, T.; Hahn, F.; Haider, S.; Harvey, J.; Hay, B.; Hernando Morata, J.-A.; Herranz Alvarez, J.; van Herwijnen, E.; Hilke, H. J.; von Holtey, G.; Hulsbergen, W.; Jacobsson, R.; Jamet, O.; Joram, C.; Jost, B.; Kanaya, N.; Knaster Refolio, J.; Koestner, S.; Koratzinos, M.; Kristic, R.; Lacarrère, D.; Lasseur, C.; Lastovicka, T.; Laub, M.; Liko, D.; Lippmann, C.; Lindner, R.; Losasso, M.; Maier, A.; Mair, K.; Maley, P.; Mato Vila, P.; Moine, G.; Morant, J.; Moritz, M.; Moscicki, J.; Muecke, M.; Mueller, H.; Nakada, T.; Neufeld, N.; Ocariz, J.; Padilla Aranda, C.; Parzefall, U.; Patel, M.; Pepe-Altarelli, M.; Piedigrossi, D.; Pivk, M.; Pokorski, W.; Ponce, S.; Ranjard, F.; Riegler, W.; Renaud, J.; Roiser, S.; Rossi, A.; Roy, L.; Ruf, T.; Ruffinoni, D.; Saladino, S.; Sambade Varela, A.; Santinelli, R.; Schmelling, S.; Schmidt, B.; Schneider, T.; Schöning, A.; Schopper, A.; Seguinot, J.; Snoeys, W.; Smith, A.; Smith, A. C.; Somogyi, P.; Stoica, R.; Tejessy, W.; Teubert, F.; Thomas, E.; Toledo Alarcon, J.; Ullaland, O.; Valassi, A.; Vannerem, P.; Veness, R.; Wicht, P.; Wiedner, D.; Witzeling, W.; Wright, A.; Wyllie, K.; Ypsilantis, T.

    2008-08-01

    The LHCb experiment is dedicated to precision measurements of CP violation and rare decays of B hadrons at the Large Hadron Collider (LHC) at CERN (Geneva). The initial configuration and expected performance of the detector and associated systems, as established by test beam measurements and simulation studies, is described.

  3. Cerenkov fiber sampling calorimeters

    SciTech Connect

    Arrington, K.; Kefford, D.; Kennedy, J.; Pisani, R.; Sanzeni, C.; Segall, K.; Wall, D.; Winn, D.R. ); Carey, R.; Dye, S.; Miller, J.; Sulak, L.; Worstell, W. ); Efremenko, Y.; Kamyshkov, Y.; Savin, A.; Shmakov, K.; Tarkovsky, E. )

    1994-08-01

    Clear optical fibers were used as a Cerenkov sampling media in Pb (electromagnetic) and Cu (hadron) absorbers in spaghetti calorimeters, for high rate and high radiation dose experiments, such as the forward region of high energy colliders. The fiber axes were aligned close to the direction of the incident particles (1[degree]--7[degree]). The 7 [lambda] deep hadron tower contained 2.8% by volume 1.5 mm diameter core clear plastic fibers. The 27 radiation length deep electromagnetic towers had packing fractions of 6.8% and 7.2% of 1 mm diameter core quartz fibers as the active Cerenkov sampling medium. The energy resolution on electrons and pions, energy response, pulse shapes and angular studies are presented.

  4. The CDF miniplug calorimeters

    SciTech Connect

    Lami, Stefano

    2002-06-28

    Two MiniPlug calorimeters, designed to measure the energy and lateral position of particles in the (forward) pseudorapidity region of 3.6 < |{nu}| < 5.2 of the CDF detector, have been recently installed as part of the Run II CDF upgrade at the Tevatron {bar p}p collider. They consist of lead/liquid scintillator read out by wavelength shifting fibers arranged in a pixel-type towerless geometry suitable for ''calorimetric tracking''. The design concept, the prototype performance and the final design of the MiniPlugs are here described. A recent cosmic ray test resulted in a light yield of approximately 100 pe/MIP, which exceeds our design requirements.

  5. The CMS central hadron calorimeter

    SciTech Connect

    Freeman, J.

    1998-11-01

    The CMS central hadron calorimeter is a brass absorber/scintillator sampling structure. We describe details of the mechanical and optical structure. We also discuss calibration techniques, and finally the anticipated construction schedule. {copyright} {ital 1998 American Institute of Physics.}

  6. Containerless high temperature calorimeter apparatus

    NASA Technical Reports Server (NTRS)

    Lacy, L. L.; Nisen, D. B. (Inventor)

    1981-01-01

    A calorimeter apparatus for measuring high temperature thermophysical properties of materials is disclosed which includes a containerless heating apparatus in which the specimen is suspended and heated by electron bombardment.

  7. Muon g-2 Calorimeter Prototypes

    SciTech Connect

    Polly, Chris; /Fermilab

    2010-05-03

    The proposed design is a tungsten-scintillating fiber calorimeter with 35 segments, each read out by a separate PMT. Tungsten, which is significantly denser than lead, produces compact showers. This is necessary, in order to improve shower separation in analysis and to fully contain the showers within a calorimeter that satisfies the strict space constraints of the experiment. A single calorimeter segment (4 x 6 x 15 cm{sup 3}) has been constructed in order establish the feasibility of the new design and study its properties. Initial tests of the detector segment at the Paul Scherrer Institute were conducted with a low energy < 400 MeV/c electron beam. A higher-energy test with electrons up to a few GeV/c was performed at the Test Beam Facility under the experimental number T-967. All data from that test have been analyzed and published, and the tungsten-scintillating fiber calorimeter still appears to be a viable candidate. For this test beam run, a larger calorimeter (15 x 15 x 11 cm{sup 3}) has been constructed and an emphasis will be placed on understanding shower leakage and the ability to separate pileup events with a more granular readout. The experimenters will measure the energy resolution, linearity, and shower size of the calorimeter segment. This will provide important information for finalizing decisions on the angle of the fibers relative to the incoming electrons and the optimal granularity of the readout.

  8. Performance of the DELPHI small angle tile calorimeter

    SciTech Connect

    Alvsvaag, S.J.; Maeland, O.A.; Klovning, A.

    1996-06-01

    The DELPHI STIC detector is a lead-scintillator sampling calorimeter with wave length shifting optical fibers used for light collection. The main goal of the calorimeter at LEP100 is to measure the luminosity with an accuracy better than 0.1%. The detector has been in operation since the 1994 LEP run. Presented here is the performance measured during the 1994--1995 LEP runs, with the emphasis on the achieved energy and space resolution, the long-term stability and the efficiency of the detector. The new bunchtrains mode of LEP requires a rather sophisticated trigger and timing scheme which is also presented. To control the trigger efficiency and stability of the calorimeter channels, a LED-based monitoring system has been developed.

  9. The LHCb DAQ interface board TELL1

    NASA Astrophysics Data System (ADS)

    Haefeli, G.; Bay, A.; Gong, A.; Gong, H.; Muecke, M.; Neufeld, N.; Schneider, O.

    2006-05-01

    We have developed an electronic board (TELL1) to interface the DAQ system of the LHCb experiment at CERN. 289 TELL1 boards are needed to read out the different subdetectors. Each board can handle either 64 analog or 24 digital optical links. The TELL1 mother board provides common mode correction, zero suppression, data formatting, and a large network interface buffer. To satisfy the different requirements we have adopted a flexible FPGA design and made use of mezzanine cards. Mezzanines are used for data input from digital optical and analog copper links as well as for the Gigabit Ethernet interface to DAQ. The LHCb timing and trigger control signals are transported by a dedicated optical link, while the board slow-control is provided by an embedded PC running a Linux kernel.

  10. Performance of the LHCb Vertex Locator

    NASA Astrophysics Data System (ADS)

    Leflat, Alexander

    2012-08-01

    LHCb is a dedicated experiment to study new physics in the decays of beauty and charm hadrons at the Large Hadron Collider (LHC) at CERN. The VELO is the silicon detector surrounding the LHCb interaction point, and is located only 7 mm from the LHC beam during normal operation. The VELD is moved into position for each fill of the LHC, once stable beams are obtained. The VELO consists of two retractable detector halves with 21 silicon micro-strip tracking modules each. A module is composed of two n+-on-n 300 micron thick half disc sensors with R-measuring and Phi-measuring micro-strip geometry, mounted on a carbon fiber support. The VELO has been successfully operated for the first LHC physics run. Operational results show a signal to noise ratio of around 20:1 and a cluster finding efficiency relative to the design of 99.5%.

  11. The LHCb silicon tracker: running experience

    NASA Astrophysics Data System (ADS)

    Saornil Gamarra, S.

    2013-02-01

    The LHCb Silicon Tracker is part of the main tracking system of the LHCb detector at the LHC. It measures very precisely the particle trajectories coming from the interaction point in the region of high occupancies around the beam axis. It covers the full acceptance angle in front of the dipole magnet in the Tracker Turicensis station and the innermost part around the beam axis in the three Inner Tracker stations downstream of the magnet. The Silicon Tracker covers a sensitive area of 12 m2 using silicon micro-strip sensors with very long readout strips. We report on running experience for the experiment. Focussing on electronic and hardware issues we describe some of the lessons learned and pitfalls encountered after three years of successful operation.

  12. Upgrade of the Upstream Tracker at LHCb

    NASA Astrophysics Data System (ADS)

    Andrews, Jason; LHCb Collaboration

    2015-04-01

    The LHCb detector will be upgraded to allow it operate at higher collider luminosity without the need for a hardware trigger stage. Flavor enriched events will be selected in a software based, high level trigger, using fully reconstructed events. This presentation will describe the design, optimization and the expected performance of the Upstream Tracker (UT), which has a critical role in high level trigger scheme.

  13. LHCb results from proton ion collisions

    NASA Astrophysics Data System (ADS)

    Massacrier, Laure

    2016-07-01

    Proton-lead and lead-proton data taking during 2013 has allowed LHCb to expand its physics program to heavy ion physics. Results include the first forward measurement of Z production in proton-lead collisions as well as a measurement of the nuclear modification factor and forward-backward production of prompt and displaced J/ψ, ψ(2S) and ϒ. Angular particle correlations have also been measured for events of varying charged particle activity.

  14. CKM angle γ measurements at LHCb

    NASA Astrophysics Data System (ADS)

    Vallier, Alexis

    2014-11-01

    The CKM angle γ remains the least known parameter of the CKM mixing matrix. The precise measurement of this angle, as a Standard Model benchmark, is a key goal of the LHCb experiment. We present four recent CP violation studies related to the measurement of γ, including amplitude analysis of B± → DK± decays, the ADS/GLW analysis of B± → DK*0 decays and the time-dependent analysis of B± → DK±sK± decays.

  15. Performance of the LHCb silicon tracker

    NASA Astrophysics Data System (ADS)

    Cowan, G. A.; the LHCb Silicon Tracker Group

    2013-01-01

    The LHCb detector has been optimised for the search for New Physics in CP violating observables and rare heavy-quark decays at the Large Hadron Collider (LHC). The detector is a single arm forward spectrometer with excellent tracking and particle identification capabilities. The LHCb silicon tracker is constructed from silicon micro-strip detectors with long readout strips. It consists of one four-layer tracking station upstream of the LHCb spectrometer magnet and three stations downstream of the magnet. The detectors have performed extremely well right from the start of LHC operation, permitting the experiment to collect data at instantaneous luminosities well exceeding the design value. In this presentation, an overview of the operational experience from the first two years of data taking at the LHC will be given, with special emphasis on problems encountered. Calibration procedures will be discussed as well as studies of the intrinsic detector efficiency and resolution. First measurements of the observed radiation damage will also be shown.

  16. Optimization of the LHCb track reconstruction

    NASA Astrophysics Data System (ADS)

    Storaci, Barbara

    2015-12-01

    The LHCb track reconstruction uses sophisticated pattern recognition algorithms to reconstruct trajectories of charged particles. Their main feature is the use of a Hough- transform like approach to connect track segments from different sub-detectors, allowing for having no tracking stations in the magnet of LHCb. While yielding a high efficiency, the track reconstruction is a major contributor to the overall timing budget of the software trigger of LHCb, and will continue to be so in the light of the higher track multiplicity expected from Run II of the LHC. In view of this fact, key parts of the pattern recognition have been revised and redesigned. In this document the main features which were studied are presented. A staged approach strategy for the track reconstruction in the software trigger was investigated: it allows unifying complementary sets of tracks coming from the different stages of the high level trigger, resulting in a more flexible trigger strategy and a better overlap between online and offline reconstructed tracks. Furthermore the use of parallelism was investigated, using SIMD instructions for time-critical parts of the software.

  17. DAQ Architecture for the LHCb Upgrade

    NASA Astrophysics Data System (ADS)

    Liu, Guoming; Neufeld, Niko

    2014-06-01

    LHCb will have an upgrade of its detector in 2018. After the upgrade, the LHCb experiment will run at a high luminosity of 2 × 1033 cm-2s-1. The upgraded detector will be read out at 40 MHz with a highly flexible software-based triggering strategy. The Data Acquisition (DAQ) system of LHCb reads out the data fragments from the Front-End Electronics and transports them to the High-Lever Trigger farm at an aggregate throughput of ~ 32 Tbit/s. The DAQ system will be based on high speed network technologies such as InfiniBand and/or 10/40/100 Gigabit Ethernet. Independent of the network technology, there are different possible architectures for the DAQ system. In this paper, we present our studies on the DAQ architecture, where we analyze size, complexity and relative cost. We evaluate and compare several data-flow schemes for a network-based DAQ: push, pull and push with barrel-shifter traffic shaping. We also discuss the requirements and overall implications of the data-flow schemes on the DAQ system.

  18. Flow Type Bio-Chemical Calorimeter with Micro Differential Thermopile Sensor.

    PubMed

    Saito, Masataka; Nakabeppu, Osamu

    2015-04-01

    Bio-chemical calorimeters with a MEMS (Micro-Electro-Mechanical Systems) thermopile sensor have been studied for monitoring detailed processes of the biochemical reactions of a minute sample with a high temporal resolution. The bio-calorimeters are generally divided into a batch-type and a flow-type. We developed a highly sensitive batch-type calorimeter which can detect a 100 nW level thermal reaction. However it shows a long settling time of 2 hours because of the heat capacity of a whole calorimeter. Thus, the flow-type calorimeters in passive and active mode have been studied for measuring the thermal reactions in an early stage after starting an analysis. The flow-type calorimeter consists of the MEMS differential thermopile sensor, a pair of micro channel reactor in a PDMS (polydimethylsiloxane) sheet in a three-fold thermostat chamber. The calorimeter in the passive mode was tested with dilution reactions of ethanol to water and NaCl aqueous solution to water. It was shown that the calorimeter detects exo- and endothermic reaction over 250 nW at solution flow rate of 0.05 ~ 1 µl/min with a settling time of about 4 minutes. In the active mode, a response test was conducted by using heat removal by water flow from the reactor channel. The active calorimetry enhances the response time about three to four times faster. PMID:26353514

  19. Improvements to the User Interface for LHCb's Software continuous integration system.

    NASA Astrophysics Data System (ADS)

    Clemencic, M.; Couturier, B.; Kyriazi, S.

    2015-12-01

    The purpose of this paper is to identify a set of steps leading to an improved interface for LHCb's Nightly Builds Dashboard. The goal is to have an efficient application that meets the needs of both the project developers, by providing them with a user friendly interface, as well as those of the computing team supporting the system, by providing them with a dashboard allowing for better monitoring of the build job themselves. In line with what is already used by LHCb, the web interface has been implemented with the Flask Python framework for future maintainability and code clarity. The Database chosen to host the data is the schema-less CouchDB[7], serving the purpose of flexibility in document form changes. To improve the user experience, we use JavaScript libraries such as JQuery[11].

  20. Thermal dynamics of bomb calorimeters

    NASA Astrophysics Data System (ADS)

    Lyon, Richard E.

    2015-12-01

    The thermal dynamics of bomb calorimeters are modeled using a lumped heat transfer analysis in which heat is released in a pressure vessel/bomb immersed in a stirred water bath that is surrounded by a static air space bounded by an insulated (static) jacket, a constant/controlled temperature jacket (isoperibol), or a changing temperature (adiabatic) jacket. The temperature history of the water bath for each of these boundary conditions (methods) is well described by the two-term solution for the calorimeter response to a heat impulse (combustion), allowing the heat transfer coefficients and thermal capacities of the bomb and water bath to be determined parametrically. The validated heat transfer model provides an expression for direct calculation of the heat released in an arbitrary process inside a bomb calorimeter using the temperature history of the water bath for each of the boundary conditions (methods). This result makes possible the direct calculation of the heat of combustion of a sample in an isoperibol calorimeter from the recorded temperature history without the need for semi-empirical temperature corrections to account for non-adiabatic behavior. Another useful result is that the maximum temperature rise of the water bath in the static jacket method is proportional to the total heat generated, and the empirical proportionality constant, which is determined by calibration, accounts for all of the heat losses and thermal lags of the calorimeter.

  1. Thermal dynamics of bomb calorimeters.

    PubMed

    Lyon, Richard E

    2015-12-01

    The thermal dynamics of bomb calorimeters are modeled using a lumped heat transfer analysis in which heat is released in a pressure vessel/bomb immersed in a stirred water bath that is surrounded by a static air space bounded by an insulated (static) jacket, a constant/controlled temperature jacket (isoperibol), or a changing temperature (adiabatic) jacket. The temperature history of the water bath for each of these boundary conditions (methods) is well described by the two-term solution for the calorimeter response to a heat impulse (combustion), allowing the heat transfer coefficients and thermal capacities of the bomb and water bath to be determined parametrically. The validated heat transfer model provides an expression for direct calculation of the heat released in an arbitrary process inside a bomb calorimeter using the temperature history of the water bath for each of the boundary conditions (methods). This result makes possible the direct calculation of the heat of combustion of a sample in an isoperibol calorimeter from the recorded temperature history without the need for semi-empirical temperature corrections to account for non-adiabatic behavior. Another useful result is that the maximum temperature rise of the water bath in the static jacket method is proportional to the total heat generated, and the empirical proportionality constant, which is determined by calibration, accounts for all of the heat losses and thermal lags of the calorimeter. PMID:26724069

  2. Precision Timing Calorimeter for High Energy Physics

    DOE PAGESBeta

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; Duarte, Javier; Pena, Cristian; Ronzhin, Anatoly; Spiropulu, Maria; Trevor, Jason; Xie, Si

    2016-04-01

    Here, we present studies on the performance and characterization of the time resolution of LYSO-based calorimeters. Results for an LYSO sampling calorimeter and an LYSO-tungsten Shashlik calorimeter are presented. We also demonstrate that a time resolution of 30 ps is achievable for the LYSO sampling calorimeter. Timing calorimetry is described as a tool for mitigating the effects due to the large number of simultaneous interactions in the high luminosity environment foreseen for the Large Hadron Collider.

  3. ARIADNE: a Tracking System for Relationships in LHCb Metadata

    NASA Astrophysics Data System (ADS)

    Shapoval, I.; Clemencic, M.; Cattaneo, M.

    2014-06-01

    The data processing model of the LHCb experiment implies handling of an evolving set of heterogeneous metadata entities and relationships between them. The entities range from software and databases states to architecture specificators and software/data deployment locations. For instance, there is an important relationship between the LHCb Conditions Database (CondDB), which provides versioned, time dependent geometry and conditions data, and the LHCb software, which is the data processing applications (used for simulation, high level triggering, reconstruction and analysis of physics data). The evolution of CondDB and of the LHCb applications is a weakly-homomorphic process. It means that relationships between a CondDB state and LHCb application state may not be preserved across different database and application generations. These issues may lead to various kinds of problems in the LHCb production, varying from unexpected application crashes to incorrect data processing results. In this paper we present Ariadne - a generic metadata relationships tracking system based on the novel NoSQL Neo4j graph database. Its aim is to track and analyze many thousands of evolving relationships for cases such as the one described above, and several others, which would otherwise remain unmanaged and potentially harmful. The highlights of the paper include the system's implementation and management details, infrastructure needed for running it, security issues, first experience of usage in the LHCb production and potential of the system to be applied to a wider set of LHCb tasks.

  4. Job prioritization and fair share in the LHCb experiment

    NASA Astrophysics Data System (ADS)

    Castellani, G.; Santinelli, R.

    2008-07-01

    The high demanding computing needs of the LHCb experiment are fulfilled by an extensive use of the Grid resources. Although these are wide and growing, they still remain finite. This paper addresses how all LHCb users can fairly access these resources and execute their tasks in an order determined by identity, group, job type and accounting information.

  5. Calorimeters for pulsed lasers: calibration.

    PubMed

    Thacher, P D

    1976-07-01

    A calibration technique is developed and tested in which a calorimeter used for single-shot laser pulse energy measurements is calibrated with reference to a cw power standard using a chopped cw laser beam. A pulsed laser is required only to obtain the relative time response of the calorimeter to a pulse. With precautions as to beam alignment and wavelength, the principal error of the technique is that of the cw standard. Calibration of two thermopiles with cone receivers showed -2.5% and -3.5% agreement with previous calibrations made by the National Bureau of Standards. PMID:20165270

  6. D-Zero Calorimeter Multiplan

    SciTech Connect

    Wintercorn, S.J.; /Fermilab

    1987-06-15

    This short report explains the parameters, and their basis, of the D-Zero calorimeter multiplan spread sheet Macintosh Multiplan worksheets have been found to be a valuable asset to the D-Zero design effort. The spread sheet contains parameters (constants) and results that come from the parameters. The full effect of changes in D-Zero calorimeter parameters can be calculated quite easily with Multiplan. When a change in a parameter is made, any results that pertain to that parameter automatically change also. This report will explain how some of the unobvious results were obtained.

  7. COE1 Calorimeter Operations Manual

    SciTech Connect

    Santi, Peter Angelo

    2015-12-15

    The purpose of this manual is to describe the operations of the COE1 calorimeter which is used to measure the thermal power generated by the radioactive decay of plutonium-bearing materials for the purposes of assaying the amount of plutonium within the material.

  8. Calorimeter Optimization for Jet Identification

    SciTech Connect

    Bower, G.

    2004-10-11

    During LCWS 1999 at Sitges, Spain, we presented a set of discriminators for reconstructing jets in high energy lepton colliders. We have extended that study by adding new event types, by adding new discriminators, and by using a neural net rather than cuts to identify jets. We apply these techniques to detector simulations to begin a study of calorimeter optimization.

  9. The CMS central hadron calorimeter

    SciTech Connect

    Freeman, J.; E892 Collaboration

    1996-12-31

    The CMS central hadron calorimeter is a copper absorber/ scintillator sampling structure. We describe design choices that led us to this concept, details of the mechanical and optical structure, and test beam results. We discuss calibration techniques, and finally the anticipated construction schedule.

  10. Barrel calorimeter of the CMD-3 detector

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  11. Barrel calorimeter of the CMD-3 detector

    SciTech Connect

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

    2015-12-15

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

  12. A GPU offloading mechanism for LHCb

    NASA Astrophysics Data System (ADS)

    Badalov, Alexey; Campora Perez, Daniel Hugo; Zvyagin, Alexander; Neufeld, Niko; Vilasis Cardona, Xavier

    2014-06-01

    The current computational infrastructure at LHCb is designed for sequential execution. It is possible to make use of modern multi-core machines by using multi-threaded algorithms and running multiple instances in parallel, but there is no way to make efficient use of specialized massively parallel hardware, such as graphical processing units and Intel Xeon/Phi. We extend the current infrastructure with an out-of-process computational server able to gather data from multiple instances and process them in large batches.

  13. SIMD studies in the LHCb reconstruction software

    NASA Astrophysics Data System (ADS)

    Cámpora Pérez, Daniel Hugo; Couturier, Ben

    2015-12-01

    During the data taking process in the LHC at CERN, millions of collisions are recorded every second by the LHCb Detector. The LHCb Online computing farm, counting around 15000 cores, is dedicated to the reconstruction of the events in real-time, in order to filter those with interesting Physics. The ones kept are later analysed Offline in a more precise fashion on the Grid. This imposes very stringent requirements on the reconstruction software, which has to be as efficient as possible. Modern CPUs support so-called vector-extensions, which extend their Instruction Sets, allowing for concurrent execution across functional units. Several libraries expose the Single Instruction Multiple Data programming paradigm to issue these instructions. The use of vectorisation in our codebase can provide performance boosts, leading ultimately to Physics reconstruction enhancements. In this paper, we present vectorisation studies of significant reconstruction algorithms. A variety of vectorisation libraries are analysed and compared in terms of design, maintainability and performance. We also present the steps taken to systematically measure the performance of the released software, to ensure the consistency of the run-time of the vectorised software.

  14. The CLAS Forward Electromagnetic Calorimeter

    SciTech Connect

    M. Amarian; Geram Asryan; Kevin Beard; Will Brooks; Volker Burkert; Tom Carstens; Alan Coleman; Raphael Demirchyan; Yuri Efremenko; Hovanes Egiyan; Kim Egiyan; Herb Funsten; Vladimir Gavrilov; Kevin L. Giovanetti; R.M. Marshall; Berhard Mecking; R.C. Minehart; H. Mkrtchan; Mavrik Ohandjanyan; Youri Sharabian; L.C. Smith; Stepan Stepanyan; W.A. Stephens; T.Y. Tung; Carl Zorn

    2001-05-01

    The CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab utilizes six iron-free superconducting coils to provide an approximately toroidal magnetic field. The six sectors are instrumented individually to form six independent spectrometers. The forward region (8deg < (theta) < 45deg) of each sector is equipped with a lead-scintillator electromagnetic sampling calorimeter (EC), 16 radiation lengths thick, using a novel triangular geometry with stereo readout. With its good energy and position resolution, the EC is used to provide the primary electron trigger for CLAS. It is also used to reject pions, reconstruct pi-0 and eta decays and detect neutrons, This paper treats the design, construction and performance of the calorimeter.

  15. Containerless high-temperature calorimeter

    NASA Technical Reports Server (NTRS)

    Lacy, L. L.; Nisen, D. B.; Robinson, M. B.

    1979-01-01

    Samples are heated by electron bombardment in high-temperature calorimeter that operates from 1,000 to 3,600 C yet consumes less that 100 watts at temperatures less than 2,500 C. Contamination of samples is kept to minimum by suspending them from wire in vacuum chamber. Various sample slopes such as wires, dishs, spheres, rods, or irregular bodies can be accommodated and only about 100 nq of samples are needed for accurate measurements.

  16. Electromagnetic Calorimeter for HADES Experiment

    NASA Astrophysics Data System (ADS)

    Rodríguez-Ramos, P.; Chlad, L.; Epple, E.; Fabbietti, L.; Galatyuk, T.; Golubeva, M.; Guber, F.; Hlaváč, S.; Ivashkin, A.; Kajetanowic, M.; Kardan, B.; Koenig, W.; Korcyl, G.; Kugler, A.; Lapidus, K.; Linev, S.; Lisowski, E.; Neiser, A.; Ott, O.; Otte, O.; Pethukov, O.; Pietraszko, J.; Reshetin, A.; Rost, A.; Salabura, P.; Sobolev, Y. G.; Svoboda, O.; Thomas, A.; Tlusty, P.; Traxler, M.

    2014-11-01

    Electromagnetic calorimeter (ECAL) is being developed to complement dilepton spectrometer HADES. ECAL will enable the HADES@FAIR experiment to measure data on neutral meson production in heavy ion collisions at the energy range of 2-10 AGeV on the beam of future accelerator SIS100@FAIR. We will report results of the last beam test with quasi-monoenergetic photons carried out in MAMI facility at Johannes Gutenberg Universität Mainz.

  17. Rugged calorimeter with a fast rise time

    SciTech Connect

    McMurtry, W.M.; Dolce, S.R.

    1980-01-01

    An intrinsic 1-mil-thick gold foil calorimeter has been developed which rises to 95% of the energy deposited in less than 2 microseconds. This calorimeter is very rugged, and can withstand rough handling without damage. The time constant is long, in the millisecond range, because of its unique construction. Use of this calorimeter has produced 100% data recovery, and agreement with true deposition to less than 10%.

  18. Upgrade of the LHCb Vertex Locator

    NASA Astrophysics Data System (ADS)

    Leflat, A.

    2014-08-01

    The upgrade of the LHCb experiment, planned for 2018, will transform the entire readout to a trigger-less system operating at 40 MHz. All data reduction algorithms will be executed in a high-level software farm, with access to all event information. This will enable the detector to run at luminosities of 1-2 × 1033/cm2/s and probe physics beyond the Standard Model in the heavy sector with unprecedented precision. The upgraded VELO must be low mass, radiation hard and vacuum compatible. It must be capable of fast pattern recognition and track reconstruction and will be required to drive data to the outside world at speeds of up to 2.5 Tbit/s. This challenge is being met with a new Vertex Locator (VELO) design based on hybrid pixel detectors positioned to within 5 mm of the LHC colliding beams. The sensors have 55 × 55 μm square pixels and the VELOPix ASIC which is being developed for the readout is based on the Timepix/Medipix family of chips. The hottest ASIC will have to cope with pixel hit rates of up to 900 MHz. The material budget will be optimised with the use of evaporative CO2 coolant circulating in microchannels within a thin silicon substrate. Microchannel cooling brings many advantages: very efficient heat transfer with almost no temperature gradients across the module, no CTE mismatch with silicon components, and low material contribution. This is a breakthrough technology being developed for LHCb. LHCb is also focussing effort on the construction of a lightweight foil to separate the primary and secondary LHC vacua, the development of high speed cables and radiation qualification of the module. The 40 MHz readout will also bring significant conceptual changes to the way in which the upgrade trigger is operated. Work is in progress to incorporate momentum and impact parameter information into the trigger at the earliest possible stage, using the fast pattern recognition capabilities of the upgraded detector. The current status of the VELO upgrade will

  19. Secondary Emission Calorimeter Sensor Development

    NASA Astrophysics Data System (ADS)

    Winn, David R.; Onel, Yasar

    2012-12-01

    In a Secondary Emission electron(SEe) detector module, Secondary Emission electrons (SEe) are generated from an SE surface/cathode, when charged hadronic or electromagnetic particles, particularly shower particles, penetrate an SE sampling module placed between absorber materials (Fe, Cu, Pb, W etc) in calorimeters. The SE cathode is a thin (10-50 nm thick) film (simple metal-oxides, or other higher yield materials) on the surface of a metal plate, which serves as the entrance “window” to a compact vacuum vessel (metal or metal-ceramic); this SE film cathode is analogous to a photocathode, and the SEe are similar to p.e., which are then amplified by dynodes, also is in a PMT. SE sensor modules can make use of electrochemically etched/machined or laser-cut metal mesh dynode sheets, as large as ~30 cm square, to amplify the Secondary Emission Electrons (SEe), much like those that compact metal mesh or mesh dynode PMT's use to amplify p.e.'s. The construction requirements easier than a PMT, since the entire final assembly can be done in air; there are no critical controlled thin film depositions, cesiation or other oxygen-excluded processes or other required vacuum activation, and consequently bake-out can be a refractory temperatures; the module is sealed by normal vacuum techniques (welding or brazing or other high temperature joinings), with a simple final heated vacuum pump-out and tip-off. The modules envisioned are compact, high gain, high speed, exceptionally radiation damage resistant, rugged, and cost effective, and can be fabricated in arbitrary tileable shapes. The SE sensor module anodes can be segmented transversely to sizes appropriate to reconstruct electromagnetic cores with high precision. The GEANT4 and existing calorimeter data estimated calorimeter response performance is between 35-50 Secondary Emission electrons per GeV, in a 1 cm thick Cu absorber calorimeter, with a gain per SEe > 105 per SEe, and an e/pi<1.2. The calorimeter pulse width is

  20. Calibration and data quality systems of the ATLAS Tile Calorimeter during the LHC Run-I operations

    NASA Astrophysics Data System (ADS)

    Ženiš, T.

    2016-07-01

    The Tile Calorimeter is the hadronic calorimeter covering the central region of the ATLAS detector at the LHC. It consists of thin steel plates and scintillating tiles. Wavelength shifting fibers coupled to the tiles collect the produced light and are read out by photomultiplier tubes. The calibration scheme of the Tile Calorimeter comprises Cs radioactive source, laser and charge injection systems. Each stage of the signal production of the calorimeter from scintillation light to digitization is monitored and equalized. Description of the different TileCal calibration systems as well as the results on their performance in terms of calibration factors, linearity and stability is given. The data quality procedures and efficiency of the Tile Calorimeter during the LHC Run-1 data-taking period are presented as well.

  1. A Universal Logging System for LHCb Online

    NASA Astrophysics Data System (ADS)

    Nikolaidis, Fotis; Brarda, Loic; Garnier, Jean-Christophe; Neufeld, Niko

    2011-12-01

    A log is recording of system's activity, aimed to help system administrator to traceback an attack, find the causes of a malfunction and generally with troubleshooting. The fact that logs are the only information an administrator may have for an incident, makes logging system a crucial part of an IT infrastructure. In large scale infrastructures, such as LHCb Online, where quite a few GB of logs are produced daily, it is impossible for a human to review all of these logs. Moreover, a great percentage of them as just "noise". That makes clear that a more automated and sophisticated approach is needed. In this paper, we present a low-cost centralized logging system which allow us to do in-depth analysis of every log.

  2. Tracking system of the upgraded LHCb

    NASA Astrophysics Data System (ADS)

    Obłąkowska-Mucha, A.; Szumlak, T.

    2016-07-01

    The upgrade of the LHCb experiment will run at an instantaneous luminosity up to 2 ×1033cm-2s-1 with a fully software based trigger, allowing us to read out the detector at a rate of 40 MHz. For this purpose, the full tracking system will be newly developed: the vertex locator (VELO) will be replaced by a pixel-based detector providing an excellent track reconstruction with an efficiency of above 99%. Upstream of the magnet, a silicon micro-strip detector with a high granularity and an improved acceptance, called the Upstream Tracker (UT) will be placed. The tracking system downstream of the magnet will be replaced by the Scintillating Fibre tracker (SciFi), which will consist of 12 layers using 2.5 m long scintillating fibres read out by silicon photo-multipliers.

  3. Spaghetti calorimeter results and prospects

    SciTech Connect

    Desalvo, R.

    1992-12-31

    In the guidelines of the SPACAL-LAA project the authors have built and beam-tested a prototype of spaghetti calorimeter with full hadronic shower containment. The results proved that the spaghetti technology (lead and scintillating fibers) can perform very accurate calorimetric measurements at the 15 ns LHC or SSC crossing rate and can compete with advantage over the other calorimetric technologies. In this paper they present the experimental results obtained so far and some future development foreseen in view of a hermetic supercollider detector.

  4. Calorimeter in the ARIES recovery system

    SciTech Connect

    Wetzel, J.R.; Sampson, T.E.; Cremers, T.L.

    1997-11-01

    The Advanced Recovery and Integrated Extraction System is an automated weapons component recovery system that includes four state-of-the-art nondestructive assay (NDA) instruments to analyze all outputs and the final product. The instruments are integrated with robotics sample handling to provide the analytical data and are controlled by a central computer. The NDA instruments are a plutonium isotopic composition system, neutron coincidence counter, segmented gamma scanner, and a calorimeter. This paper will describe the calorimeter system which uses the new Windows environment software package to communicate between the calorimeter and the control computer. Storage, retrieval, database, and operations with other software packages, such as Excel, are provided to allow the operator to analyze the calorimeter system. The host computer assumes control of all functions of the calorimeter system in the remote operations and retrieves the data upon completion of the calorimeter sample run allowing the robotics system to change samples at the earliest possible time for maximum sample throughput. The calorimeter Windows operating system allows viewing of the calorimeter, room, and bath data during the sample run. 1 ref., 2 figs., 1 tab.

  5. Status of the CDF II Calorimeters

    SciTech Connect

    Mattson, Mark

    2006-10-27

    The status of the CDF calorimeters was reported at the CALOR2002 conference, about a year after Run II started at the Tevatron Collider. I will review upgrades to the system since that conference, as well as the operation and performance of the calorimeters.

  6. Evaluation of the Argonne National Laboratory servo-controlled calorimeter system

    SciTech Connect

    Foster, L.A.

    1997-01-01

    The control system of a replacement mode, twin-bridge, water-bath calorimeter originally built by Mound EG&G Applied Technologies was modified by Argonne National Laboratory. The calorimeter was upgraded with a PC-based computer control and data acquisition system. The system was redesigned to operate in a servo-control mode, and a preheater was constructed to allow pre-equilibration of samples. The instrument was sent to the Plutonium Facility at Los Alamos National Laboratory for testing and evaluation of its performance in the field using heat source standards and plutonium process materials. The important parameters for calorimeter operation necessary to satisfy the nuclear materials control and accountability requirements of the Plutonium Facility were evaluated over a period of several months. These parameters include calorimeter stability, measurement precision and accuracy, and average measurement time. The observed measurement precision and accuracy were found to be acceptable for most accountability measurements, although they were slightly larger than the values for calorimeters in routine use at the Plutonium Facility. Average measurement times were significantly shorter than measurement times for identical items in the Plutonium Facility calorimeters. Unexplained shifts in the baseline measurements were observed on numerous occasions. These shifts could lead to substantial measurement errors if they are not very carefully monitored by the operating facility. Detailed results of the experimental evaluation are presented in this report.

  7. 5.8 X-ray Calorimeters

    NASA Technical Reports Server (NTRS)

    Porter, F. Scott

    2008-01-01

    X-ray calorimeter instruments for astrophysics have seen rapid development since they were invented in 1984. The prime instrument on all currently planned X-ray spectroscopic observatories is based on calorimeter technology. This relatively simple detection concept that senses the energy of an incident photon by measuring the temperature rise of an absorber material at very low temperatures, can form the basis of a very high performance, non-dispersive spectrometer. State-of-the-art calorimeter instruments have resolving powers of over 3000, large simultaneous band-passes, and near unit efficiency. This coupled with the intrinsic imaging capability of a pixilated x-ray calorimeter array, allows true spectral-spatial instruments to be constructed. In this chapter I briefly review the detection scheme, the state-of-the-art in X-ray calorimeter instruments and the future outlook for this technology.

  8. Radiation tolerance tests of SRAM-based FPGAs for the potential usage in the readout electronics for the LHCb experiment

    NASA Astrophysics Data System (ADS)

    Färber, C.; Uwer, U.; Wiedner, D.; Leverington, B.; Ekelhof, R.

    2014-02-01

    This paper describes radiation studies of a SRAM-based FPGA as a central component for a upgrade of the LHCb Outer Tracker front-end electronics to a readout frequency of 40 MHz. Two Arria GX FPGAs were irradiated with 20 MeV protons to radiation doses of up to 7 Mrad. During and between the irradiation periods the different FPGA currents, the package temperature, the firmware error rate, the PLL stability, and the stability of a 32 channel TDC implemented on the FPGA were monitored. Results on the radiation tolerance of the FPGA and the measured firmware error rates will be presented. The Arria GX FPGA fulfills the radiation tolerance required for the LHCb upgrade (30 krad) and an expected firmware error rate of roughly 10-6 Hz makes the chip a possible component for the upgraded front-end electronics.

  9. High-temperature containerless calorimeter

    NASA Technical Reports Server (NTRS)

    Robinson, M. B.; Lacy, L. L.

    1985-01-01

    A high-temperature (greater than 1500 K) containerless calorimeter is described and its usefulness demonstrated. The calorimeter uses the technique of omnidirectional electron bombardment of pendant drops to achieve an isothermal test environment. The small heat input into the sample (i.e., 15-50 W) can be controlled and measured. The apparatus can be used to determine the total hemispherical emissivity, specific heat, heat of fusion, surface tension, and equilibrium melting temperature of small molten drops in the temperature range of 1500 to 3500 K. The total hemispherical emissivity and specific heat of pure niobium and two alloys of niobium-germanium have been measured in the temperature range of 1700 to 2400 K. As reported in the literature, the total hemispherical emissivity varied as a function of temperature. However, specific heat values for both the pure metal and alloys seem to be independent of temperature. Specific heat for the liquid alloy phase was also measured and compared to the solid phase.

  10. ALICE electromagnetic calorimeter prototype test

    SciTech Connect

    Awes, Terry; /Oak Ridge

    2005-09-01

    This Memorandum of Understanding between the Test Beam collaborators and Fermilab is for the use of beam time at Fermilab during the Fall, 2005 Meson Test Beam Run. The experimenters plan to measure the energy, position, and time resolution of prototype modules of a large electromagnetic calorimeter proposed to be installed in the ALICE experiment at the LHC. The ALICE experiment is one of the three large approved LHC experiments, with ALICE placing special emphasis on the LHC heavy-ion program. The large electromagnetic calorimeter (EMCal) is a US initiative that is endorsed by the ALICE collaboration and is currently in the early stages of review by the Nuclear Physics Division of the DOE. The installation in the test beam at FNAL and test beam measurements will be carried out by the US members of the ALICE collaboration (ALICE-USA). The overall design of the ALICE EMCal is heavily influenced by its location within the ALICE L3 magnet. The EMCal is to be located inside the large room temperature magnet within a cylindrical integration volume approximately l12cm deep, by 5.6m in length, sandwiched between the ALICE TPC space frame and the L3 magnet coils. The chosen technology is a layered Pb-scintillator sampling calorimeter with a longitudinal pitch of 1.6mm Pb and 1.6mm scintillator. The full detector spans {eta} = -0.7 to {eta} = 0.7 with an azimuthal acceptance of {Delta}{phi} = 120{sup o}. The EMCal readout is of a ''Shish-Kabob'' type similar to the PHENIX Pb-scintillator sampling calorimeter in which the scintillation light is collected via wavelength shifting fibers running through the Pb-scintillator tiles perpendicular to the front surface. The detector is segmented into {approx}14000 towers. The basic structural units of the calorimeter are supermodules, each subtending approximately {approx}20{sup o} in {Delta}{phi} and 0.7 units in {Delta}{eta}. Supermodules are assembled from individual modules. The modules are further segmented into 2 x 2

  11. The light-harvesting chlorophyll a/b binding proteins Lhcb1 and Lhcb2 play complementary roles during state transitions in Arabidopsis.

    PubMed

    Pietrzykowska, Malgorzata; Suorsa, Marjaana; Semchonok, Dmitry A; Tikkanen, Mikko; Boekema, Egbert J; Aro, Eva-Mari; Jansson, Stefan

    2014-09-01

    Photosynthetic light harvesting in plants is regulated by phosphorylation-driven state transitions: functional redistributions of the major trimeric light-harvesting complex II (LHCII) to balance the relative excitation of photosystem I and photosystem II. State transitions are driven by reversible LHCII phosphorylation by the STN7 kinase and PPH1/TAP38 phosphatase. LHCII trimers are composed of Lhcb1, Lhcb2, and Lhcb3 proteins in various trimeric configurations. Here, we show that despite their nearly identical amino acid composition, the functional roles of Lhcb1 and Lhcb2 are different but complementary. Arabidopsis thaliana plants lacking only Lhcb2 contain thylakoid protein complexes similar to wild-type plants, where Lhcb2 has been replaced by Lhcb1. However, these do not perform state transitions, so phosphorylation of Lhcb2 seems to be a critical step. In contrast, plants lacking Lhcb1 had a more profound antenna remodeling due to a decrease in the amount of LHCII trimers influencing thylakoid membrane structure and, more indirectly, state transitions. Although state transitions are also found in green algae, the detailed architecture of the extant seed plant light-harvesting antenna can now be dated back to a time after the divergence of the bryophyte and spermatophyte lineages, but before the split of the angiosperm and gymnosperm lineages more than 300 million years ago. PMID:25194026

  12. Calibration of the Tile Hadronic Calorimeter of ATLAS at LHC

    NASA Astrophysics Data System (ADS)

    Boumediene, Djamel; ATLAS Collaboration

    2015-02-01

    The Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment. The TileCal provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses iron plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by means of wavelength shifting fibers to photomultiplier tubes (PMTs). The TileCal readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read by two PMTs. A brief description of the individual calibration systems (Cs radioactive source, laser, charge injection, minimum bias) is provided. Their combination allows to calibrate each part of the data acquisition chain (optical part, photomultiplier, readout electronics) and to monitor its stability to better than 1%. The procedure for setting and preserving the electromagnetic energy scale during Run 1 data taking is discussed. The issues of linearity and stability of the response, as well as the timing adjustment are also shown.

  13. Upgrade fo the CMS Hadron Outer Calorimeter with SIPMs

    SciTech Connect

    Anderson, Jacob; Freeman, James; Los, Sergey; Whitmore, Juliana; /Fermilab

    2011-09-14

    The CMS Hadron Outer Calorimeter (HO) is undergoing an upgrade to replace the existing photodetectors (HPDs) with SIPMs. The chosen device is the Hamamatsu 3 x 3mm 50 {mu}m pitch MPPC. The system has been developed to be a 'drop-in' replacement of the HPDs. A complete control system of bias voltage generation, leakage current monitoring, temperature monitoring, and temperature control using solid state Peltier coolers has been developed and tested. 108 channels of the system have been installed into CMS and operated for more than 2 years. The complete system of about 2200 channels is in production and will be installed in the next LHC long shutdown scheduled for 2013. The CMS central calorimeter consists of a detector inside the solenoidal magnet, HB, and a component outside the magnet, the Outer Hadron Calorimeter, HO [1]. The HO is installed inside the magnet flux return yoke and provides for typically 3{lambda} of additional absorber to the calorimetric measurement. The outer calorimeter is composed of one or more layers of scintillator with wavelength shifting fiber readout into photodetectors. Figure 1 (a) shows the schematic layout of the calorimeters in CMS and shows the location of the HO scintillator layers. The front end electronics are placed inside the CMS detector, close to the scintillators. Figure 1(b) shows a photograph of the scintillators. Note the four wavelength shifting fibers per tile. The tile size creates a projective tower with the HB. Currently the photodetector used is the HPD but for performance and operational reasons it is desired to upgrade these with SIPMs. The CMS HCAL group has developed a drop-in replacement for the HPD using SIPMs. SIPMs are very suitable for this application because of several factors: The radiation levels are modest with a lifetime expected fluence of less than 5*10{sup 11} neutrons (E > 100 KeV) per cm{sup 2}. The energy flux into HO is small, the rate of larger energy depositions is low, and the required

  14. Performance and upgrade plans of the LHCb trigger system

    NASA Astrophysics Data System (ADS)

    Gligorov, V. V.; LHCb Collaboration

    2013-08-01

    The trigger of the LHCb experiment consists of two stages: an initial hardware trigger, and a high-level trigger implemented in a farm of parallel-processing CPUs. It reduces the event rate from an input of 15 MHz to an output rate of around 4 kHz. In order to maximize efficiencies and minimize biases, the trigger is designed around inclusive selection algorithms, culminating in a novel boosted decision tree which enables the efficient selection of beauty hadron decays based on a robust partial reconstruction of their decay products. In order to improve performance, the LHCb upgrade aims to significantly increase the rate at which the detector will be read out, and hence shift more of the workload onto the high-level trigger. It is demonstrated that the current high-level trigger architecture will be able to meet this challenge, and the expected efficiencies in several key channels are discussed in context of the LHCb upgrade.

  15. B-physics prospects with the LHCb experiment

    SciTech Connect

    Harnew, N.

    2008-04-15

    This paper summarizes the B-physics prospects of the LHCb experiment. Firstly, a brief introduction to the CKM matrix and the mechanism of CP violation in the Standard Model is given. The advantages of the LHCb experiment for B-physics exploitation will then be described, together with a short description of the detector components. Finally, the LHCb physics aims and prospects will be summarized, focusing on the measurements of sin(2{beta}) in tree and gluonic penguin diagrams, sin(2{alpha}) in B{sub d}{sup 0} {sup {yields}} {pi}{sup +}{pi}{sup -} and {pi}{sup +}{pi}{sup -}{pi}{sup 0}, neutral B-meson oscillations and the B{sub s}{sup 0} mixing phase, and the measurement of {gamma} using a variety of complementary methods.

  16. LHCb Build and Deployment Infrastructure for run 2

    NASA Astrophysics Data System (ADS)

    Clemencic, M.; Couturier, B.

    2015-12-01

    After the successful run 1 of the LHC, the LHCb Core software team has taken advantage of the long shutdown to consolidate and improve its build and deployment infrastructure. Several of the related projects have already been presented like the build system using Jenkins, as well as the LHCb Performance and Regression testing infrastructure. Some components are completely new, like the Software Configuration Database (using the Graph DB Neo4j), or the new packaging installation using RPM packages. Furthermore all those parts are integrated to allow easier and quicker releases of the LHCb Software stack, therefore reducing the risk of operational errors. Integration and Regression tests are also now easier to implement, allowing to improve further the software checks.

  17. Searching supersymmetry at the LHCb with displaced vertices

    SciTech Connect

    Campos, F. de; Eboli, O. J. P.; Magro, M. B.; Restrepo, D.

    2009-03-01

    Supersymmetric theories with bilinear R-parity violation can give rise to the observed neutrino masses and mixings. One important feature of such models is that the lightest supersymmetric particle might have a sufficiently large lifetime to produce detached vertices. Working in the framework of supergravity models, we analyze the potential of the LHCb experiment to search for supersymmetric models exhibiting bilinear R-parity violation. We show that the LHCb experiment can probe a large fraction of the m{sub 0} x m{sub 1/2}, being able to explore gluino masses up to 1.3 TeV. The LHCb discover potential for these kinds of models is similar to the ATLAS and CMS ones in the low luminosity phase of operation of the LHC.

  18. The upgraded LHCb RICH detector: Status and perspectives

    NASA Astrophysics Data System (ADS)

    Cardinale, R.

    2016-07-01

    The LHCb upgrade will take place during the second long shutdown of the LHC (LS2). The upgrade will enable the experiment to run at an instantaneous luminosity of 2 ×1033cm-2s-1 and will read out data at a rate of 40 MHz into a flexible software-based trigger. The two Ring Imaging Cherenkov detectors (RICH), installed in the LHCb experiment, will be re-designed to comply with these new operating conditions. The status and perspective of the RICH upgrade project will be presented.

  19. First LHC beam induced tracks reconstructed in the LHCb VELO

    NASA Astrophysics Data System (ADS)

    Parkes, C.; Borghi, S.; Bates, A.; Eklund, L.; Gersabeck, M.; Marinho, F.; Rakotomiaramanana, B.; Rodrigues, E.; Szumlak, T.; Affolder, A.; Bowcock, T.; Casse, G.; Donleavy, S.; Hennessy, K.; Huse, T.; Hutchcroft, D.; Mylroie-Smith, J.; Noor, A.; Patel, G.; Rinnert, K.; Smith, N. A.; Shears, T.; Tobin, M.; John, M.; Bay, A.; Frei, R.; Haefeli, G.; Keune, A.; Anderson, J.; McNulty, R.; Traynor, S.; Basiladze, S.; Leflat, A.; Artuso, M.; Borgia, A.; Lefeuvre, G.; Mountain, R.; Wang, J.; Akiba, K.; van Beuzekom, M.; Jans, E.; Ketel, T.; Mous, I.; Papadelis, A.; Van Lysebetten, A.; Verlaat, B.; de Vries, H.; Behrendt, O.; Buytaert, J.; de Capua, S.; Collins, P.; Ferro-Luzzi, M.

    2009-06-01

    The Vertex Locator of the LHCb experiment has been used to fully reconstruct beam induced tracks at the LHC. A beam of protons was collided with a beam absorber during the LHC synchronisation test of the anti-clockwise beam on the weekend 22nd-24th August 2008. The resulting particles have been observed by the Vertex Locator. The LHCb Vertex Locator is a silicon micro-strip detector containing 21 planes of modules. Tracks were observed passing through up to 19 modules (38 silicon sensors). A total of over 700 tracks were reconstructed, and are being used to study the calibration and alignment of the detector.

  20. High-Density, Scintillating, Fluoride Glass Calorimeters

    NASA Astrophysics Data System (ADS)

    Akgun, Ugur; Xie, Qiuchen

    2014-03-01

    The unprecedented radiation levels in current Large Hadron Collider runs, and plans to even increase the luminosity creates a need for new detector technologies to be investigated. Here, we propose to use high density, scintillating, fluoride glasses as active media in calorimeters. CHG3 is a special example of this glass family, which has been developed specifically for hadron collider experiments, and is known for fast response time, in addition to high light yield. In this presentation, the results from a computational study on the performances of the two different designs of CHG3 glass calorimeters are reported. First design reads the signal directly from the edge of the glass plate; the second design utilizes wavelength-shifting fibers to carry the signal out of the glass plate. Each simulation model is a sampling calorimeter with 20 alternating layers of glass and iron absorber. By changing the absorber thickness we tested hadronic as well as electromagnetic capabilities of the calorimeter models.

  1. Uranium scintillator calorimeter at the CERN ISR

    SciTech Connect

    Gordon, H; Killian, T; Ludlam, T

    1980-01-01

    The design, Monte Carlo studies and test beam results of a uranium/scintillator calorimeter to be installed in the Intersecting Storage Ring (ISR) at CERN are described. In its final stage the calorimeter will cover the full azimuth over a polar region of 45/sup 0/ < theta < 135/sup 0/. The full calorimeter is built in a modular way from 128 stacks, with each stack internally subdivided into six cells of 20 x 20 cm/sup 2/ cross section. The readout is by wavelength shifting (WLS) plates with a separate readout of the front part of the calorimeter (first ten plates) to allow electromagnetic/hadronic separation. Since the readout plates are on both sides of the cells, position information is obtained from the left/right ratio.

  2. Barrel Calorimeter for the Hall D Spectrometer

    SciTech Connect

    David Urner

    1998-06-01

    The barrel calorimeter for the hall D spectrometer is discussed for standard pointing geometry and a parallel geometry using Lead Scintillating fibres as active material. A comparison with a CSI spectrometer is shown.

  3. CDF End Plug calorimeter Upgrade Project

    SciTech Connect

    Apollinari, G.; de Barbaro, P.; Mishina, M.

    1994-01-01

    We report on the status of the CDF End Plug Upgrade Project. In this project, the CDF calorimeters in the end plug and the forward regions will be replaced by a single scintillator based calorimeter. After an extensive R&D effort on the tile/fiber calorimetry, we have now advanced to a construction phase. We review the results of the R&D leading to the final design of the calorimeters and the development of tooling devised for this project. The quality control program of the production of the electromagnetic and hadronic calorimeters is described. A shower maximum detector for the measurement of the shower centroid and the shower profile of electrons, {gamma} and {pi}{sup 0} has been designed. Its performance requirements, R&D results and mechanical design are discussed.

  4. The CMS central hadron calorimeter: Update

    SciTech Connect

    Freeman, J.

    1998-06-01

    The CMS central hadron calorimeter is a brass absorber/ scintillator sampling structure. We describe details of the mechanical and optical structure. We also discuss calibration techniques, and finally the anticipated construction schedule.

  5. The BaBar electromagnetic calorimeter

    SciTech Connect

    Stahl, A.

    1997-07-01

    The progress on the design and construction of the BaBar electromagnetic calorimeter including its mechanical structure, the readout system, the mechanical and optical properties of the crystals, and the schedule for the final assembly and testing is summarized.

  6. The DELPHI small angle tile calorimeter

    SciTech Connect

    Alvsvaag, S.J.; Maeland, O.A.; Klovning, A.

    1995-08-01

    The Small angle TIle Calorimeter (STIC) provides calorimetric coverage in the very forward region for the DELPHI experiment at the CERN LEP collider. A veto system composed of two scintillator layers allows to trigger on single photon events and provides e{minus}{gamma} separation. The authors present here some results of extensive measurements performed on part of the calorimeter and the veto system in the CERN test beams prior to installation and report on the performance achieved during the 1994 LEP run.

  7. Accelerator Test of an Imaging Calorimeter

    NASA Technical Reports Server (NTRS)

    Christl, Mark J.; Adams, James H., Jr.; Binns, R. W.; Derrickson, J. H.; Fountain, W. F.; Howell, L. W.; Gregory, J. C.; Hink, P. L.; Israel, M. H.; Kippen, R. M.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The Imaging Calorimeter for ACCESS (ICA) utilizes a thin sampling calorimeter concept for direct measurements of high-energy cosmic rays. The ICA design uses arrays of small scintillating fibers to measure the energy and trajectory of the produced cascades. A test instrument has been developed to study the performance of this concept at accelerator energies and for comparison with simulations. Two test exposures have been completed using a CERN test beam. Some results from the accelerator tests are presented.

  8. Commissioning and calibration of the Zero Degree Calorimeters for the ALICE experiment

    NASA Astrophysics Data System (ADS)

    Gemme, R.; Arnaldi, R.; Chiavassa, E.; Cicalò, C.; Cortese, P.; De Falco, A.; Dellacasa, G.; De Marco, N.; Ferretti, A.; Floris, M.; Gagliardi, M.; Gallio, M.; Luparello, G.; Masoni, A.; Mereu, P.; Musso, A.; Oppedisano, C.; Piccotti, A.; Poggio, F.; Puddu, G.; Scomparin, E.; Serci, S.; Siddi, E.; Stocco, D.; Usai, G.; Vercellin, E.

    2009-12-01

    The ALICE experiment at the CERN LHC will study the properties of matter at the extreme temperature and energy density conditions produced in heavy ion collisions. The impact parameter of the collision will be estimated by means of the Zero Degree Calorimeters (ZDC), that measure the energy carried away by the non-interacting (spectator) nucleons. All the spectator nucleons have the same energy, therefore the calorimeter response is proportional to their number, providing a direct information on the centrality of the collision. Two identical sets of hadronic calorimeters are located at opposite sides with respect to the interaction point, 116 m away from it, where the two LHC beams circulate in two different pipes. Each set of detectors consists of a neutron (ZN) calorimeter, placed between the two beam pipes and a proton (ZP) calorimeter, positioned externally to the outgoing beam pipe. The ZDC are spaghetti calorimeters, which detect the Cherenkov light produced by the charged particles of the shower in the quartz fibers, acting as the active material embedded in a dense absorber matrix. In summer 2007 the ZN and ZP calorimeters have been placed on a movable platform and then installed in the LHC tunnel. The results of the commissioning studies are shown. The monitoring systems adopted to control the stability of the PMT responses, i.e. light injection with a laser diode and cosmic rays, are described in detail. The foreseen calibration with e.m. dissociation events in Pb-Pb collisions will also be discussed. Finally the first measurements carried out during the commissioning in the LHC tunnel will be presented.

  9. Performance of the LHCb Vertex Locator

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Affolder, A.; Akiba, K.; Alexander, M.; Ali, S.; Appleby, R. B.; Artuso, M.; Bates, A.; Bay, A.; Behrendt, O.; Benton, J.; van Beuzekom, M.; Bjørnstad, P. M.; Bogdanova, G.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; van den Brand, J.; Brown, H.; Buytaert, J.; Callot, O.; Carroll, J.; Casse, G.; Collins, P.; De Capua, S.; Doets, M.; Donleavy, S.; Dossett, D.; Dumps, R.; Eckstein, D.; Eklund, L.; Farinelli, C.; Farry, S.; Ferro-Luzzi, M.; Frei, R.; Garofoli, J.; Gersabeck, M.; Gershon, T.; Gong, A.; Gong, H.; Gordon, H.; Haefeli, G.; Harrison, J.; Heijne, V.; Hennessy, K.; Hulsbergen, W.; Huse, T.; Hutchcroft, D.; Jaeger, A.; Jalocha, P.; Jans, E.; John, M.; Keaveney, J.; Ketel, T.; Korolev, M.; Kraan, M.; Laštovička, T.; Lafferty, G.; Latham, T.; Lefeuvre, G.; Leflat, A.; Liles, M.; van Lysebetten, A.; MacGregor, G.; Marinho, F.; McNulty, R.; Merkin, M.; Moran, D.; Mountain, R.; Mous, I.; Mylroie-Smith, J.; Needham, M.; Nikitin, N.; Noor, A.; Oblakowska-Mucha, A.; Papadelis, A.; Pappagallo, M.; Parkes, C.; Patel, G. D.; Rakotomiaramanana, B.; Redford, S.; Reid, M.; Rinnert, K.; Rodrigues, E.; Saavedra, A. F.; Schiller, M.; Schneider, O.; Shears, T.; Silva Coutinho, R.; Smith, N. A.; Szumlak, T.; Thomas, C.; van Tilburg, J.; Tobin, M.; Velthuis, J.; Verlaat, B.; Viret, S.; Volkov, V.; Wallace, C.; Wang, J.; Webber, A.; Whitehead, M.; Zverev, E.

    2014-09-01

    The Vertex Locator (VELO) is a silicon microstrip detector that surrounds the proton-proton interaction region in the LHCb experiment. The performance of the detector during the first years of its physics operation is reviewed. The system is operated in vacuum, uses a bi-phase CO2 cooling system, and the sensors are moved to 7 mm from the LHC beam for physics data taking. The performance and stability of these characteristic features of the detector are described, and details of the material budget are given. The calibration of the timing and the data processing algorithms that are implemented in FPGAs are described. The system performance is fully characterised. The sensors have a signal to noise ratio of approximately 20 and a best hit resolution of 4 μm is achieved at the optimal track angle. The typical detector occupancy for minimum bias events in standard operating conditions in 2011 is around 0.5%, and the detector has less than 1% of faulty strips. The proximity of the detector to the beam means that the inner regions of the n+-on-n sensors have undergone space-charge sign inversion due to radiation damage. The VELO performance parameters that drive the experiment's physics sensitivity are also given. The track finding efficiency of the VELO is typically above 98% and the modules have been aligned to a precision of 1 μm for translations in the plane transverse to the beam. A primary vertex resolution of 13 μm in the transverse plane and 71 μm along the beam axis is achieved for vertices with 25 tracks. An impact parameter resolution of less than 35 μm is achieved for particles with transverse momentum greater than 1 GeV/c.

  10. Virtualization for the LHCb Online system

    NASA Astrophysics Data System (ADS)

    Bonaccorsi, Enrico; Brarda, Loic; Moine, Gary; Neufeld, Niko

    2011-12-01

    Virtualization has long been advertised by the IT-industry as a way to cut down cost, optimise resource usage and manage the complexity in large data-centers. The great number and the huge heterogeneity of hardware, both industrial and custom-made, has up to now led to reluctance in the adoption of virtualization in the IT infrastructure of large experiment installations. Our experience in the LHCb experiment has shown that virtualization improves the availability and the manageability of the whole system. We have done an evaluation of available hypervisors / virtualization solutions and find that the Microsoft HV technology provides a high level of maturity and flexibility for our purpose. We present the results of these comparison tests, describing in detail, the architecture of our virtualization infrastructure with a special emphasis on the security for services visible to the outside world. Security is achieved by a sophisticated combination of VLANs, firewalls and virtual routing - the cost and benefits of this solution are analysed. We have adapted our cluster management tools, notably Quattor, for the needs of virtual machines and this allows us to migrate smoothly services on physical machines to the virtualized infrastructure. The procedures for migration will also be described. In the final part of the document we describe our recent R&D activities aiming to replacing the SAN-backend for the virtualization by a cheaper iSCSI solution - this will allow to move all servers and related services to the virtualized infrastructure, excepting the ones doing hardware control via non-commodity PCI plugin cards.

  11. An imaging calorimeter for ACCESS concept study

    NASA Astrophysics Data System (ADS)

    Parnell, T. A.; Adams, J. H.; Binns, R. W.; Christl, M. J.; Derrickson, J. H.; Fountain, W. F.; Howell, L. W.; Gregory, J. C.; Hink, P. L.; Israel, M. H.; Kippen, R. M.; Lee, J.; Pendleton, G. N.; Takahashi, Y.; Watts, J. W.

    2001-08-01

    A mission concept study to define the "Advanced Cosmic-ray Composition Experiment for Space Station (ACCESS)" was sponsored by the National Aeronautics and Space Administration (NASA). The ACCESS instrument complement contains a transition radiation detector and an ionization calorimeter to measure the spectrum of protons, helium, and heavier nuclei up to ~1015 eV to search for the limit of S/N shock wave acceleration, or evidence for other explanations of the spectra. Several calorimeter configurations have been studied, including the "baseline" totally active bismuth germanate instrument and sampling calorimeters utilizing various detectors. The Imaging Calorimeter for ACCESS (ICA) concept comprises a carbon target and a calorimeter using a high atomic number absorber sampled approximately each radiation length (rl) by thin scintillating fiber (SCIFI) detectors. The main features and options of the ICA instrument configuration are described in this paper. Since direct calibration is not possible over most of the energy range, the best approach must be decided from simulations of calorimeter performance extrapolated from CERN calibrations at 0.375 TeV. This paper presents results from the ICA simulations study.

  12. On the anomalies in the latest LHCb data

    NASA Astrophysics Data System (ADS)

    Hurth, T.; Mahmoudi, F.; Neshatpour, S.

    2016-08-01

    Depending on the assumptions on the power corrections to the exclusive b → sℓ+ℓ- decays, the latest data of the LHCb Collaboration - based on the 3 fb-1 data set and on two different experimental analysis methods - still shows some tensions with the Standard Model predictions. We present a detailed analysis of the theoretical inputs and various global fits to all the available b → sℓ+ℓ- data. This constitutes the first global analysis of the new data of the LHCb Collaboration based on the hypothesis that these tensions can be at least partially explained by new physics contributions. In our model-independent analysis we present one-, two-, four-, and also five-dimensional global fits in the space of Wilson coefficients to all available b → sℓ+ℓ- data. We also compare the two different experimental LHCb analyses of the angular observables in B →K*μ+μ-. We explicitly analyse the dependence of our results on the assumptions about power corrections, but also on the errors present in the form factor calculations. Moreover, based on our new global fits we present predictions for ratios of observables which may show a sign of lepton non-universality. Their measurements would crosscheck the LHCb result on the ratio RK = BR (B+ →K+μ+μ-) / BR (B+ →K+e+e-) in the low-q2 region which deviates from the SM prediction by 2.6σ.

  13. Tritium calorimeter setup and operation

    SciTech Connect

    Rodgers, David E.

    2002-12-17

    The LBNL tritium calorimeter is a stable instrument capable of measuring tritium with a sensitivity of 25 Ci. Measurement times range from 8-hr to 7-days depending on the thermal conductivity and mass of the material being measured. The instrument allows accurate tritium measurements without requiring that the sample be opened and subsampled, thus reducing personnel exposure and radioactive waste generation. The sensitivity limit is primarily due to response shifts caused by temperature fluctuation in the water bath. The fluctuations are most likely a combination of insufficient insulation from ambient air and precision limitations in the temperature controller. The sensitivity could probably be reduced to below 5 Ci if the following improvements were made: (1) Extend the external insulation to cover the entire bath and increase the top insulation. (2) Improve the seal between the air space above the bath and the outside air to reduce evaporation. This will limit the response drift as the water level drops. (3) Install an improved temperature controller, preferably with a built in chiller, capable of temperature control to {+-}0.001 C.

  14. Calorimeter Timing System at CDF

    SciTech Connect

    Goncharov, Max

    2006-10-27

    We report on the design and performance of the electromagnetic calorimeter timing readout system (EMTiming) for the Collider Detector at Fermilab (CDF). The system is used in searches for rare events with high-energy photons to verify that the photon is in time with the event collision, and to reject cosmic-ray and beam-halo backgrounds. The installation and commissioning of all 862 channels was completed in Fall 2004 as part of an upgrade to the Run II version of the detector. Using in-situ data, we measure the energy threshold for a time to be recorded to be 3.8{+-}0.3 GeV and 1.9{+-}0.1 GeV in the central (CEM) and plug (PEM) portions of the detector. Similarly, for the central and plug portions we measure a timing resolution of 600{+-}10 ps and 610{+-}10 ps for electrons above 10 GeV (6 GeV). Pathologies such as noise and non-Gaussian tails are virtually non-existent.

  15. Recent and planned changes to the LHCb computing model

    NASA Astrophysics Data System (ADS)

    Cattaneo, M.; Charpentier, P.; Clarke, P.; Roiser, S.

    2014-06-01

    The LHCb experiment [1] has taken data between December 2009 and February 2013. The data taking conditions and trigger rate were adjusted several times during this period to make optimal use of the luminosity delivered by the LHC and to extend the physics potential of the experiment. By 2012, LHCb was taking data at twice the instantaneous luminosity and 2.5 times the high level trigger rate than originally foreseen. This represents a considerable increase in the amount of data which had to be handled compared to the original Computing Model from 2005, both in terms of compute power and in terms of storage. In this paper we describe the changes that have taken place in the LHCb computing model during the last 2 years of data taking to process and analyse the increased data rates within limited computing resources. In particular a quite original change was introduced at the end of 2011 when LHCb started to use for reprocessing compute power that was not co-located with the RAW data, namely using Tier2 sites and private resources. The flexibility of the LHCbDirac Grid interware allowed easy inclusion of these additional resources that in 2012 provided 45% of the compute power for the end-of-year reprocessing. Several changes were also implemented in the Data Management model in order to limit the need for accessing data from tape, as well as in the data placement policy in order to cope with a large imbalance in storage resources at Tier1 sites. We also discuss changes that are being implemented during the LHC Long Shutdown 1 (LS1) to prepare for a further doubling of the data rate when the LHC restarts at a higher energy in 2015.

  16. Evolutionary loss of light-harvesting proteins Lhcb6 and Lhcb3 in major land plant groups - break-up of current dogma.

    PubMed

    Kouřil, Roman; Nosek, Lukáš; Bartoš, Jan; Boekema, Egbert J; Ilík, Petr

    2016-05-01

    Photosynthesis in plants and algae relies on the coordinated function of photosystems (PS) I and II. Their efficiency is augmented by finely-tuned light-harvesting proteins (Lhcs) connected to them. The most recent Lhcs (in evolutionary terms), Lhcb6 and Lhcb3, evolved during the transition of plants from water to land and have so far been considered to be an essential characteristic of land plants. We used single particle electron microscopy and sequence analysis to study architecture and composition of PSII supercomplex from Norway spruce and related species. We have found that there are major land plant families that lack functional lhcb6 and lhcb3 genes, which notably changes the organization of PSII supercomplexes. The Lhcb6 and Lhcb3 proteins have been lost in the gymnosperm genera Picea and Pinus (family Pinaceae) and Gnetum (Gnetales). We also revealed that the absence of these proteins in Norway spruce modifies the PSII supercomplex in such a way that it resembles its counterpart in the alga Chlamydomonas reinhardtii, an evolutionarily older organism. Our results break a deep-rooted concept of Lhcb6 and Lhcb3 proteins being the essential characteristic of land plants, and beg the question of what the evolutionary benefit of their loss could be. PMID:27001142

  17. Description of an ionization calorimeter complemented with proportional counters

    NASA Technical Reports Server (NTRS)

    Babayan, K. P.; Boyadzhyan, N. G.; Vasiltsov, V. V.; Grigorov, N. L.; Sobinyakov, V. A.; Shestoperov, V. Y.

    1975-01-01

    An ionization calorimeter is described with a system of proportional counters which are used to determine the charge of the particles incident to the calorimeter and to estimate the number of the secondary charged particles.

  18. The Imaging Calorimeter for ACCESS (ICA)

    NASA Astrophysics Data System (ADS)

    Parnell, Thomas

    A mission concept study to define the "Advanced Cosmic-ray Composition Experiment for Space Station (ACCESS)" is being sponsored by the National Aeronautics and Space Administration (NASA). The ACCESS instrument complement contains an ionization calorimeter to measure the spectrum of protons, helium, and heavier nuclei up to ~1015 eV to search for the limit of S/N shock wave acceleration. Several calorimeters are under study, including the "baseline" totally active bismuth germanate instrument and sampling calorimeters utilizing various detectors. The ICA comprises a carbon target and a high atomic number absorber sampled approximately each radiation length (rl) by thin scintillating fiber (SCIFI) detectors. The main features of the ICA instrument concept are described in this paper.

  19. Vacuum-jacketed hydrofluoric acid solution calorimeter

    USGS Publications Warehouse

    Robie, R.A.

    1965-01-01

    A vacuum-jacketed metal calorimeter for determining heats of solution in aqueous HF was constructed. The reaction vessel was made of copper and was heavily gold plated. The calorimeter has a cooling constant of 0.6 cal-deg -1-min-1, approximately 1/4 that of the air-jacketed calorimeters most commonly used with HF. It reaches equilibrium within 10 min after turning off the heater current. Measurements of the heat of solution of reagent grade KCl(-100 mesh dried 2 h at 200??C) at a mole ratio of 1 KCl to 200 H2O gave ??H = 4198??11 cal at 25??C. ?? 1965 The American Institute of Physics.

  20. Calibration of the CDF tile-fiber endplug calorimeters using moving radioactive sources

    SciTech Connect

    Barnes, V.; Laasanen, A.; Pompos, A.; Wilson, M.

    1998-11-01

    The use of moving radioactive gamma sources to assess, calibrate and monitor scintillating tile calorimeters is discussed, and the techniques and equipment are described. The capabilities of the technique are illustrated using Cs{sup 137} sources with the CDF Endplug Upgrade EM and Hadron calorimeters at testbeams and at a cosmic ray test stand. Source measurements of all the tiles in testbeam modules which are exact replicas of the calorimeters, predict the relative responses of EM towers to 50 GeV positrons and muons, and of Hadron towers to 50 GeV pions, with RMS accuracies of 1.3{percent}, 1.8{percent} and 2.0{percent}, respectively. Source measurements will be used in lieu of testbeam measurements for the initial calibration of all towers in the final calorimeters. Source measurements of single tiles are reproducible to 0.4{percent} and will be used to monitor gain changes of the photomultiplier tubes. {copyright} {ital 1998 American Institute of Physics.}

  1. Precision Crystal Calorimeters in High Energy Physics

    ScienceCinema

    Ren-Yuan Zhu

    2010-01-08

    Precision crystal calorimeters traditionally play an important role in high energy physics experiments. In the last two decades, it faces a challenge to maintain its precision in a hostile radiation environment. This paper reviews the performance of crystal calorimeters constructed for high energy physics experiments and the progress achieved in understanding crystal?s radiation damage as well as in developing high quality scintillating crystals for particle physics. Potential applications of new generation scintillating crystals of high density and high light yield, such as LSO and LYSO, in particle physics experiments is also discussed.

  2. Floating data acquisition system for microwave calorimeter measurements on MTX

    SciTech Connect

    Sewall, N.R.; Meassick, S. )

    1989-09-13

    A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles are located inside the tokamak about 1 cm outside of the limiter radius at machine potential. The success of this measurement depends on our ability to float the data acquisition system near machine potential and isolate it from the rest of the vault ground system. Our data acquisition system has 48 channels of thermistor signal conditioning, a multiplexer and digitizer section, a serial data formatter, and a fiber-optic transmitter to send the data out. Additionally, we bring timing signals to the interface through optical fibers to tell it when to begin measurement, while maintaining isolation. The receiver is an HP 200 series computer with a serial data interface; the computer provides storage and local display for the shot temperature profile. Additionally, the computer provides temporary storage of the data until it can be passed to a shared resource management system for archiving. 2 refs., 6 figs.

  3. A PCIe Gen3 based readout for the LHCb upgrade

    NASA Astrophysics Data System (ADS)

    Bellato, M.; Collazuol, G.; D'Antone, I.; Durante, P.; Galli, D.; Jost, B.; Lax, I.; Liu, G.; Marconi, U.; Neufeld, N.; Schwemmer, R.; Vagnoni, V.

    2014-06-01

    The architecture of the data acquisition system foreseen for the LHCb upgrade, to be installed by 2018, is devised to readout events trigger-less, synchronously with the LHC bunch crossing rate at 40 MHz. Within this approach the readout boards act as a bridge between the front-end electronics and the High Level Trigger (HLT) computing farm. The baseline design for the LHCb readout is an ATCA board requiring dedicated crates. A local area standard network protocol is implemented in the on-board FPGAs to read out the data. The alternative solution proposed here consists in building the readout boards as PCIe peripherals of the event-builder servers. The main architectural advantage is that protocol and link-technology of the event-builder can be left open until very late, to profit from the most cost-effective industry technology available at the time of the LHC LS2.

  4. Z' models for the LHCb and g -2 muon anomalies

    NASA Astrophysics Data System (ADS)

    Allanach, Ben; Queiroz, Farinaldo S.; Strumia, Alessandro; Sun, Sichun

    2016-03-01

    We revisit a class of Z' explanations of the anomalies found by the LHCb collaboration in B decays, and show that the scenario is tightly constrained by a combination of constraints: (i) LHC searches for dimuon resonances, (ii) perturbativity of the Z' couplings; (iii) the Bs mass difference, and (iv) electroweak precision data. Solutions are found by suppressing the Z' coupling to electrons and to light quarks and/or by allowing for a Z' decay width into dark matter. We also present a simplified framework where a TeV-scale Z' gauge boson that couples to standard leptons as well as to new heavy vectorlike leptons, can simultaneously accommodate the LHCb anomalies and the muon g -2 anomaly.

  5. Event Index — an LHCb Event Search System

    NASA Astrophysics Data System (ADS)

    Ustyuzhanin, A.; Artemov, A.; Kazeev, N.; Redkin, A.

    2015-12-01

    During LHC Run 1, the LHCb experiment recorded around 1011 collision events. This paper describes Event Index — an event search system. Its primary function is to quickly select subsets of events from a combination of conditions, such as the estimated decay channel or number of hits in a subdetector. Event Index is essentially Apache Lucene [1] optimized for read-only indexes distributed over independent shards on independent nodes.

  6. Tracking with the LHCb spectrometer: Detector performance and track reconstruction

    NASA Astrophysics Data System (ADS)

    Tuning, N.; LHCb Collaboration

    2007-10-01

    The LHCb experiment aims to measure CP violation and rare B-decays. For this, a tracking system is constructed consisting of a silicon micro-strip vertex locator close to the interaction point, and tracking detectors around a dipole magnet. The resulting tracking performance is estimated from simulation to yield 95% efficiency. The momentum and impact parameter resolutions vary between 0.35% and 0.5%, and 20 and 160 μm, respectively.

  7. The LHCb VERTEX LOCATOR performance and VERTEX LOCATOR upgrade

    NASA Astrophysics Data System (ADS)

    Rodríguez Pérez, P.

    2012-12-01

    LHCb is an experiment dedicated to the study of new physics in the decays of beauty and charm hadrons at the Large Hadron Collider (LHC) at CERN. The Vertex Locator (VELO) is the silicon detector surrounding the LHCb interaction point. The detector operates in a severe and highly non-uniform radiation environment. The small pitch and analogue readout result in a best single hit precision of 4 μm. The upgrade of the LHCb experiment, planned for 2018, will transform the entire readout to a trigger-less system operating at 40 MHz event rate. The vertex detector will have to cope with radiation levels up to 1016 1 MeVneq/cm2, more than an order of magnitude higher than those expected at the current experiment. A solution is under development with a pixel detector, based on the Timepix/Medipix family of chips with 55 x 55 μm pixels. In addition a micro-strip solution is also under development, with finer pitch, higher granularity and lower mass than the current detector. The current status of the VELO will be described together with recent testbeam results.

  8. Status and upgrade of the LHCb Vertex Locator

    NASA Astrophysics Data System (ADS)

    Gersabeck, M.

    2014-06-01

    The LHCb Vertex Locator (VELO) is the detector responsible for the detection of heavy hadrons through their flight distance. The performance of the VELO during its three years of operation during the LHC physics runs is presented, focussing on the latest studies. The primary results presented are the first observation of type-inversion at the LHC; a comparison of n-type and p-type silicon in operation; and the observation of a radiation-induced charge loss effect due to the presence of a second metal layer. The upgrade of the LHCb experiment, planned for 2018, will transform the entire readout to a trigger-less system operating at 40 MHz. The upgraded VELO must be light weight, radiation hard, and compatible with LHC vacuum requirements. The material budget will be optimised with the use of evaporative CO2 coolant circulating in micro-channels within a thin silicon substrate. The current status of the VELO upgrade will be described together with a presentation of recent test results, and a discussion of the R&D on alternative solutions which has been carried out within the LHCb VELO upgrade programme.

  9. Comparative Investigation of Shared Filesystems for the LHCb Online Cluster

    NASA Astrophysics Data System (ADS)

    Vijay Kartik, S.; Neufeld, Niko

    2012-12-01

    This paper describes the investigative study undertaken to evaluate shared filesystem performance and suitability in the LHCb Online environment. Particular focus is given to the measurements and field tests designed and performed on an in-house OpenAFS setup; related comparisons with NFSv4 and GPFS (a clustered filesystem from IBM) are presented. The motivation for the investigation and the test setup arises from the need to serve common user-space like home directories, experiment software and control areas, and clustered log areas. Since the operational requirements on such user-space are stringent in terms of read-write operations (in frequency and access speed) and unobtrusive data relocation, test results are presented with emphasis on file-level performance, stability and “high-availability” of the shared filesystems. Use cases specific to the experiment operation in LHCb, including the specific handling of shared filesystems served to a cluster of 1500 diskless nodes, are described. Issues of prematurely expiring authenticated sessions are explicitly addressed, keeping in mind long-running analysis jobs on the Online cluster. In addition, quantitative test results are also presented with alternatives including NFSv4. Comparative measurements of filesystem performance benchmarks are presented, which are seen to be used as reference for decisions on potential migration of the current storage solution deployed in the LHCb online cluster.

  10. Performance of the GEM electromagnetic calorimeter

    SciTech Connect

    Hong Ma

    1993-06-25

    The GEM EM calorimeter is optimized for the best energy, position, angular resolution and jet rejection. The detailed simulation results are presented. In the barrel with LKr, an energy resolution of about 6%/{radical}{direct_sum}0.4%, pointing resolution of 40mrad/{radical}E + 0.5mrad, and jet rejection of a factor of 5 are expected.

  11. Grout Analysis for EC and CC Calorimeters

    SciTech Connect

    Engstrom, L.L.; /Fermilab

    1987-01-06

    The EC and CC calorimeters roll on Two parallel hardened steel ways which reside on the top of the D0 platform's center beam. The ways will be grouted to the center beam once their correct elevation has been established. The purpose of this report is to evaluate and compare three different epoxy grouts and their properties for this application.

  12. SLD liquid argon calorimeter prototype test results

    SciTech Connect

    Dubois, R.; Eigen, G.; Au, Y.; Sleeman, J.; Breidenbach, M.; Brau, J.; Ludgate, G.A.; Oram, C.J.; Cook, V.; Johnson, J.

    1985-10-01

    The results of the SLD test beam program for the selection of a calorimeter radiator composition within a liquid argon system are described, with emphasis on the study of the use of uranium to obtain equalization of pion and electron responses.

  13. Jobs masonry in LHCb with elastic Grid Jobs

    NASA Astrophysics Data System (ADS)

    Stagni, F.; Charpentier, Ph

    2015-12-01

    In any distributed computing infrastructure, a job is normally forbidden to run for an indefinite amount of time. This limitation is implemented using different technologies, the most common one being the CPU time limit implemented by batch queues. It is therefore important to have a good estimate of how much CPU work a job will require: otherwise, it might be killed by the batch system, or by whatever system is controlling the jobs’ execution. In many modern interwares, the jobs are actually executed by pilot jobs, that can use the whole available time in running multiple consecutive jobs. If at some point the available time in a pilot is too short for the execution of any job, it should be released, while it could have been used efficiently by a shorter job. Within LHCbDIRAC, the LHCb extension of the DIRAC interware, we developed a simple way to fully exploit computing capabilities available to a pilot, even for resources with limited time capabilities, by adding elasticity to production MonteCarlo (MC) simulation jobs. With our approach, independently of the time available, LHCbDIRAC will always have the possibility to execute a MC job, whose length will be adapted to the available amount of time: therefore the same job, running on different computing resources with different time limits, will produce different amounts of events. The decision on the number of events to be produced is made just in time at the start of the job, when the capabilities of the resource are known. In order to know how many events a MC job will be instructed to produce, LHCbDIRAC simply requires three values: the CPU-work per event for that type of job, the power of the machine it is running on, and the time left for the job before being killed. Knowing these values, we can estimate the number of events the job will be able to simulate with the available CPU time. This paper will demonstrate that, using this simple but effective solution, LHCb manages to make a more efficient use of

  14. X-Ray Calorimeter Arrays for Astrophysics

    NASA Technical Reports Server (NTRS)

    Kilbourne, Caroline A.

    2009-01-01

    High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. The grating spectrometers on the XMM and Chandra satellites started a new era in x-ray astronomy, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and can enable imaging spectroscopy of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can distinguish tens of thousands of x-ray colors. The potential benefits to astrophysics of using a low-temperature calorimeter to determine the energy of an incident x-ray photon via measurement of a small change in temperature was first articulated by S. H. Moseley over two decades ago. In the time since, technological progress has been steady, though full realization in an orbiting x-ray telescope is still awaited. A low-temperature calorimeter can be characterized by the type of thermometer it uses, and three types presently dominate the field. The first two types are temperature-sensitive resistors - semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a paramagnetic thermometer. These types can be considered the three generations of x-ray calorimeters; by now each has demonstrated a resolving power of 2000 at 6 keV, but only a semiconductor calorimeter system has been developed to spaceflight readiness. The Soft X-ray Spectrometer on Astro-H, expected to launch in 2013, will use an array of silicon thermistors with I-IgTe x-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays, kilo-pixel arrays of the superconducting calorimeters are just now being produced, and it is anticipated that much larger arrays will require the non-dissipative advantage of magnetic thermometers.

  15. Optimization of operation of a three-electrode gyrotron with the use of a flow-type calorimeter

    SciTech Connect

    Kharchev, Nikolay K.; Batanov, German M.; Kolik, Leonid V.; Malakhov, Dmitrii V.; Petrov, Aleksandr Ye.; Sarksyan, Karen A.; Skvortsova, Nina N.; Stepakhin, Vladimir D.; Belousov, Vladimir I.; Malygin, Sergei A.; Tai, Yevgenii M.

    2013-01-15

    Results are presented for measurements of microwave power of the Borets-75/0.8 gyrotron with recovery of residual electron energy, which were performed by a flow-type calorimeter. This gyrotron is a part of the ECR plasma heating complex put into operation in 2010 at the L-2M stellarator. The new calorimeter is capable of measuring microwave power up to 0.5 MW. Monitoring of the microwave power makes it possible to control the parameters of the gyrotron power supply unit (its voltage and current) and the magnetic field of the cryomagnet in order to optimize the gyrotron operation and arrive at maximum efficiency.

  16. Optimization of operation of a three-electrode gyrotron with the use of a flow-type calorimeter.

    PubMed

    Kharchev, Nikolay K; Batanov, German M; Kolik, Leonid V; Malakhov, Dmitrii V; Petrov, Aleksandr Ye; Sarksyan, Karen A; Skvortsova, Nina N; Stepakhin, Vladimir D; Belousov, Vladimir I; Malygin, Sergei A; Tai, Yevgenii M

    2013-01-01

    Results are presented for measurements of microwave power of the Borets-75/0.8 gyrotron with recovery of residual electron energy, which were performed by a flow-type calorimeter. This gyrotron is a part of the ECR plasma heating complex put into operation in 2010 at the L-2M stellarator. The new calorimeter is capable of measuring microwave power up to 0.5 MW. Monitoring of the microwave power makes it possible to control the parameters of the gyrotron power supply unit (its voltage and current) and the magnetic field of the cryomagnet in order to optimize the gyrotron operation and arrive at maximum efficiency. PMID:23387650

  17. Effect of dead material in a calorimeter

    SciTech Connect

    Green, D.

    1995-10-01

    The existence of dead material in any practical calorimeter system is simply a fact of life. The task for the designer, then, is to understand the impact on the Physics in question, and strive to minimize it. The aim of this note is to use the ``Hanging File`` test data, which has fined grained individual readout of about 100 depth segments, to explore impact of dead material on the mean and r.m.s. of the hadronic distribution. The amount and location of the dead material is varied. It important to remember that the Hanging File data was calibrated, EM to HCAL compartment, so as to minimize the electron to pion energy dependence. In practical terms e/pie was made = 1.0 at an incident energy of about 100 GeV. Note that the PB(EM) + FE(HCAL) calorimeter was not a compensating device.

  18. Advanced Thin Ionization Calorimeter (ATIC) Update

    NASA Technical Reports Server (NTRS)

    Ahn, H. S.; Ganel, O.; Kim, K. C.; Seo, E. S.; Sina, R.; Wang, J. Z.; Wu, J.; Case, G.; Ellison, S. B.; Gould, R.; Six, N. Frank (Technical Monitor)

    2002-01-01

    The Advanced Thin Ionization Calorimeter (ATIC) experiment is designed to measure the composition and energy spectra of Z = 1 to 28 cosmic rays over the energy range of approximately 10 GeV - 100 TeV. ATIC is comprised of an eight-layer, 18 radiation length deep Bismuth Germanate (BGO) calorimeter, downstream of a 0.75 nuclear interaction length graphite target and an approximately 1 sq m finely segmented silicon charge detector. Interleaved with the graphite layers are three scintillator strip hodoscopes for pre-triggering and tracking. ATIC flew for the first time on a Long Duration Balloon (LDB) launched from McMurdo, Antarctica in January 2001. During its 16-day flight ATIC collected more than 30 million science events, along with housekeeping, calibration, and rate data. This presentation will describe the ATIC data processing, including calibration and efficiency corrections, and show results from analysis of this dataset. The next launch is planned for December 2002.

  19. Level-2 Calorimeter Trigger Upgrade at CDF

    SciTech Connect

    Flanagan, G.U.; /Purdue U.

    2007-04-01

    The CDF Run II Level-2 calorimeter trigger is implemented in hardware and is based on an algorithm used in Run I. This system insured good performance at low luminosity obtained during the Tevatron Run II. However, as the Tevatron instantaneous luminosity increases, the limitations of the current system due to the algorithm start to become clear. In this paper, we will present an upgrade of the Level-2 calorimeter trigger system at CDF. The upgrade is based on the Pulsar board, a general purpose VME board developed at CDF and used for upgrading both the Level-2 tracking and the Level-2 global decision crate. This paper will describe the design, hardware and software implementation, as well as the advantages of this approach over the existing system.

  20. Nose-cone calorimeter: PHENIX forward upgrade

    NASA Astrophysics Data System (ADS)

    Chvala, Ondrej

    2009-07-01

    PHENIX is a high rate experiment efficient at measuring rare processes, but has limited acceptance in azimuth and pseudorapidity ( η). The Nose Cone Calorimeter (NCC), a W-Si sampling calorimeter in the region of 0.9< η<3, is one of the upgrades which will significantly increase coverage in both azimuth and pseudorapidity. The NCC will expand PHENIX’s precision measurements of electromagnetic probes in η, reconstruct jets, perform a wide scope of correlation measurements, and enhance triggering capabilities. The detector will significantly contribute to measurements of γ-jet correlations, quarkonia production, and low- x nuclear structure functions. This report discusses details of the detector design and its performance concerning a sample of the physics topics which will benefit from the NCC. In view of recent funding difficulties, outlook of the activities is discussed.

  1. Shashlik calorimeter Beam-test results

    NASA Astrophysics Data System (ADS)

    Badier, J.; Busson, Ph.; Charlot, C.; Dobrzynski, L.; Tanaka, R.; Bordalo, P.; Ramos, S.; Bityukov, S.; Obraztsov, V.; Ostankov, A.; Zaitchenko, A.; Gninenko, S.; Guschin, E.; Issakov, V.; Mussienko, Y.; Semenjuk, I.

    1994-08-01

    Results from an extensive study of nonprojective Shashlik calorimeter prototypes are reported. Nine (47 × 47 mm 2) towers were exposed to a high energy electron beam at CERN SPS and read out by silicon photodiodes followed by low noise preamplifiers. The main results are the measurements of the energy and shower position resolution and the angular resolution of the electron shower direction. The shower direction measurement is encouraging being in agreement at the tower center with a resolution of σθ(mrad) = 70/√ E (10 mrad for 50 GeV electrons). The uniformity of the calorimeter response is found to be better than ± 1%. The mean light yield measured in Shashlik towers equipped with Kuraray Y7 WLS fibres and aluminized at the front end of the tower is of the order of 13 photons/MeV.

  2. A FOrward CALorimeter Upgrade For PHENIX

    SciTech Connect

    Hollis, Richard S.

    2011-06-01

    Over the past few years, the PHENIX detector has undergone several upgrades in the forward region (1<|{eta}|<4), initially covered only by the muon arms. The focus of these upgrades is toward a better understanding of the Color-Glass Condensate and the interplay between the different components of the proton's spin valence/sea quark and gluon contributions. This paper highlights the newly proposed forward calorimeter detector, FOCAL. FOCAL is a tungsten-silicon sampling calorimeter with high position and energy resolution, covering a pseudorapidity of 1.6<{eta}<2.5. This future detector aims to constrain the current view of gluon saturation at small x in the Color-Glass Condensate framework, through isolation of direct photons at high-p{sub T} over a broad range of pseudorapidity.

  3. Performance of the HPC calorimeter in DELPHI

    SciTech Connect

    Chan, A.; Crawley, H.B.; Edsall, D.M. |

    1995-08-01

    The performance of the High-density Projection Chamber (HPC), the barrel electromagnetic calorimeter of the DELPHI experiment, is described. The detector adopts the time projection technique in order to obtain exceptionally fine spatial granularity in the three coordinates ({approximately}2{times}20 mrad{sup 2} in {theta}{times}{phi} with nine samplings along the shower axes), using a limited number of readout channels (18,432). Among the various topics concerning the HPC construction and operation, major emphasis is given to the aspects related to the calibration in energy of the calorimeter, based mainly on the analysis of the detector response to {sup 83m}Kr decays, and to the treatment of aging in the readout proportional counters.

  4. The dry heat exchanger calorimeter system

    SciTech Connect

    Renz, D.P.; Wetzel, J.R.; James, S.J.; Kasperski, P.W.; Duff, M.F.

    1991-01-01

    A radiometric isothermal heat flow calorimeter and preconditioner system that uses air instead of water as the heat exchange medium has been developed at Mound. The dry heat exchanger calorimeter is 42 inches high by 18 inches in diameter and the preconditioner is a 22 inch cube, making it extremely compact compared to existing units. The new system is ideally suited for transportable, stand-alone, or glovebox applications. Preliminary tests of the system have produced sample measurements with standard deviations less than 0.25% and sample errors less than 0.50%. These tests have shown that the dry heat exchanger system will yield acceptance data with an accuracy comparable to those of Mound water bath systems now in use. 4 figs., 1 tab.

  5. LYSO crystal calorimeter readout with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Berra, A.; Bonvicini, V.; Cecchi, C.; Germani, S.; Guffanti, D.; Lietti, D.; Lubrano, P.; Manoni, E.; Prest, M.; Rossi, A.; Vallazza, E.

    2014-11-01

    Large area Silicon PhotoMultipliers (SiPMs) are the new frontier of the development of readout systems for scintillating detectors. A SiPM consists of a matrix of parallel-connected silicon micropixels operating in limited Geiger-Muller avalanche mode, and thus working as independent photon counters with a very high gain (~106). This contribution presents the performance in terms of linearity and energy resolution of an electromagnetic homogeneous calorimeter composed of 9 ~ 18X0 LYSO crystals. The crystals were readout by 36 4×4 mm2 SiPMs (4 for each crystal) produced by FBK-irst. This calorimeter was tested at the Beam Test Facility at the INFN laboratories in Frascati with a single- and multi-particle electron beam in the 100-500 MeV energy range.

  6. Phosphorylation of the Light-Harvesting Complex II Isoform Lhcb2 Is Central to State Transitions1[OPEN

    PubMed Central

    Cariti, Federica; Fucile, Geoffrey; Goldschmidt-Clermont, Michel

    2015-01-01

    Light-harvesting complex II (LHCII) is a crucial component of the photosynthetic machinery, with central roles in light capture and acclimation to changing light. The association of an LHCII trimer with PSI in the PSI-LHCII supercomplex is strictly dependent on LHCII phosphorylation mediated by the kinase STATE TRANSITION7, and is directly related to the light acclimation process called state transitions. In Arabidopsis (Arabidopsis thaliana), the LHCII trimers contain isoforms that belong to three classes: Lhcb1, Lhcb2, and Lhcb3. Only Lhcb1 and Lhcb2 can be phosphorylated in the N-terminal region. Here, we present an improved Phos-tag-based method to determine the absolute extent of phosphorylation of Lhcb1 and Lhcb2. Both classes show very similar phosphorylation kinetics during state transition. Nevertheless, only Lhcb2 is extensively phosphorylated (>98%) in PSI-LHCII, whereas phosphorylated Lhcb1 is largely excluded from this supercomplex. Both isoforms are phosphorylated to different extents in other photosystem supercomplexes and in different domains of the thylakoid membranes. The data imply that, despite their high sequence similarity, differential phosphorylation of Lhcb1 and Lhcb2 plays contrasting roles in light acclimation of photosynthesis. PMID:26438789

  7. Performance of the ATLAS Tile Hadronic Calorimeter at LHC in Run 1 and planned upgrades

    NASA Astrophysics Data System (ADS)

    Solovyanov, O.

    2014-10-01

    The Tile Calorimeter (TileCal) is the central section of the ATLAS hadronic calorimeter at the Large Hadron Collider, a key detector for the measurements of hadrons, jets, tau leptons and missing transverse energy. Scintillation light produced in the tiles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs). The resulting electronic signals from approximately 10000 PMTs are digitized before being transferred to off-detector data-acquisition systems. The data quality procedures used during the LHC data-taking and the evolution of the detector status are explained in the presentation. The energy and the time reconstruction performance of the digitized signals is presented and the noise behaviour and its improvement during the detector consolidation in maintenance periods are shown. A set of calibration systems allow monitoring and equalization of the calorimeter channels responses via signal sources that act at every stage of the signal path, from scintillation light to digitized signal. These partially overlapping systems are described in detail, their individual performance is discussed as well as the comparative results from measurements of the evolution of the calorimeter response with time during the full LHC data-taking period. The TileCal upgrade aims at replacing the majority of the on- and off-detector electronics so that all calorimeter signals will be directly digitized and sent to the off-detector electronics in the counting room. To achieve the required reliability, redundancy has been introduced at different levels. For the off-detector electronics a special pre-processor board is being developed, which will take care of the initial trigger processing, while the main data are temporarily stored in the pipeline and de-randomiser memories.

  8. VeloPix: the pixel ASIC for the LHCb upgrade

    NASA Astrophysics Data System (ADS)

    Poikela, T.; De Gaspari, M.; Plosila, J.; Westerlund, T.; Ballabriga, R.; Buytaert, J.; Campbell, M.; Llopart, X.; Wyllie, K.; Gromov, V.; van Beuzekom, M.; Zivkovic, V.

    2015-01-01

    The LHCb Vertex Detector (VELO) will be upgraded in 2018 along with the other subsystems of LHCb in order to enable full readout at 40 MHz, with the data fed directly to the software triggering algorithms. The upgraded VELO is a lightweight hybrid pixel detector operating in vacuum in close proximity to the LHC beams. The readout will be provided by a dedicated front-end ASIC, dubbed VeloPix, matched to the LHCb readout requirements and the 55 × 55 μm VELO pixel dimensions. The chip is closely related to the Timepix3, from the Medipix family of ASICs. The principal challenge that the chip has to meet is a hit rate of up to 900 Mhits/s, resulting in a required output bandwidth of more than 16 Gbit/s. The occupancy across the chip is also very non-uniform, and the radiation levels reach an integrated 400 Mrad over the lifetime of the detector.VeloPix is a binary pixel readout chip with a data driven readout, designed in 130 nm CMOS technology. The pixels are combined into groups of 2 × 4 super pixels, enabling a shared logic and a reduction of bandwidth due to combined address and time stamp information. The pixel hits are combined with other simultaneous hits in the same super pixel, time stamped, and immediately driven off-chip. The analog front-end must be sufficiently fast to accurately time stamp the data, with a small enough dead time to minimize data loss in the most occupied regions of the chip. The data is driven off chip with a custom designed high speed serialiser. The current status of the ASIC design, the chip architecture and the simulations will be described.

  9. The ATLAS Liquid Argon Electromagnetic Calorimeter

    SciTech Connect

    Carminati, L.

    2005-10-12

    The construction of the ATLAS Liquid Argon Electromagnetic calorimeter has been completed and commissioning is in progress. After a brief description of the detector layout, readout electronics and calibration, a review of the present status of the integration and the detector qualification is reported. Finally a selection of performance results obtained during several test beams will be presented with particular attention to linearity, uniformity, position reconstruction and {gamma}/{pi}0 separation.

  10. Metallic Magnetic Calorimeters for Absolute Activity Measurement

    NASA Astrophysics Data System (ADS)

    Loidl, M.; Leblanc, E.; Rodrigues, M.; Bouchard, J.; Censier, B.; Branger, T.; Lacour, D.

    2008-05-01

    We present a prototype of metallic magnetic calorimeters that we are developing for absolute activity measurements of low energy emitting radionuclides. We give a detailed description of the realization of the prototype, containing an 55Fe source inside the detector absorber. We present the analysis of first data taken with this detector and compare the result of activity measurement with liquid scintillation counting. We also propose some ways for reducing the uncertainty on the activity determination with this new technique.

  11. A no-load RF calorimeter

    NASA Technical Reports Server (NTRS)

    Chernoff, R. C.

    1975-01-01

    The described device can be used to measure the output of any dc powered RF source. No dummy load is required for the measurements. The device is, therefore, called the 'no-load calorimeter' (NLC). The NLC measures the power actually fed to the antenna or another useful load. It is believed that the NLC can compete successfully with directional coupler type systems in measuring the output of high-power RF sources.

  12. An absorbed dose calorimeter for IMRT dosimetry

    NASA Astrophysics Data System (ADS)

    Duane, S.; Aldehaybes, M.; Bailey, M.; Lee, N. D.; Thomas, C. G.; Palmans, H.

    2012-10-01

    A new calorimeter for dosimetry in small and complex fields has been built. The device is intended for the direct determination of absorbed dose to water in moderately small fields and in composite fields such as IMRT treatments, and as a transfer instrument calibrated against existing absorbed dose standards in conventional reference conditions. The geometry, materials and mode of operation have been chosen to minimize detector perturbations when used in a water phantom, to give a reasonably isotropic response and to minimize the effects of heat transfer when the calorimeter is used in non-reference conditions in a water phantom. The size of the core is meant to meet the needs of measurement in IMRT treatments and is comparable to the size of the air cavity in a type NE2611 ionization chamber. The calorimeter may also be used for small field dosimetry. Initial measurements in reference conditions and in an IMRT head and neck plan, collapsed to gantry angle zero, have been made to estimate the thermal characteristics of the device, and to assess its performance in use. The standard deviation (estimated repeatability) of the reference absorbed dose measurements was 0.02 Gy (0.6%).

  13. An improved single crystal adsorption calorimeter

    NASA Astrophysics Data System (ADS)

    Stuck, A.; Wartnaby, C. E.; Yeo, Y. Y.; Stuckless, J. T.; Al-Sarraf, N.; King, D. A.

    1996-04-01

    Significant improvements to the single crystal adsorption calorimeter (SCAC) of Borroni-Bird and King are described. The calorimeter comprises a pulsed molecular beam source, an ultrathin single crystal and an infrared detector. It is calibrated using a chopped laser beam, and the amount of gas adsorbed or reacted per pulse is measured using the King and Wells reflection detector technique. Refinements in the molecular beam system, the optical calibration system, flux calibration system and sticking probability measurement technique have been made. The calorimeter response is accurately linear over a useful energy range; the detection limit is estimated as 10 kJ mol -1; and the accuracy in heats of adsorption for heats above ˜ 80 kJ mol -1 is estimated as ˜ 6%. Comparisons of calorimetric heats with isosteric heats and with desorption energies obtained for reversible systems, such as CO on Ni and Pt single crystal surfaces, generally yield good agreement and give support to the estimate for the absolute accuracy of the instrument.

  14. Fast Shower Simulation in the ATLAS Calorimeter

    SciTech Connect

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

    2011-11-08

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

  15. Precision timing calorimeter for high energy physics

    NASA Astrophysics Data System (ADS)

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; Duarte, Javier; Peña, Cristián; Spiropulu, Maria; Trevor, Jason; Xie, Si; Ronzhin, Anatoly

    2016-07-01

    Scintillator based calorimeter technology is studied with the aim to achieve particle detection with a time resolution on the order of a few 10 ps for photons and electrons at energies of a few GeV and above. We present results from a prototype of a 1.4×1.4×11.4 cm3 sampling calorimeter cell consisting of tungsten absorber plates and Cerium-doped Lutetium Yttrium Orthosilicate (LYSO) crystal scintillator plates. The LYSO plates are read out with wave lengths shifting fibers which are optically coupled to fast photo detectors on both ends of the fibers. The measurements with electrons were performed at the Fermilab Test Beam Facility (FTBF) and the CERN SPS H2 test beam. In addition to the baseline setup plastic scintillation counter and a MCP-PMT were used as trigger and as a reference for a time of flight measurement (TOF). We also present measurements with a fast laser to further characterize the response of the prototype and the photo sensors. All data were recorded using a DRS4 fast sampling digitizer. These measurements are part of an R&D program whose aim is to demonstrate the feasibility of building a large scale electromagnetic calorimeter with a time resolution on the order of 10 ps, to be used in high energy physics experiments.

  16. The Zeus calorimeter first level trigger

    SciTech Connect

    Smith, W.J.

    1989-04-01

    The design of the Zeus Detector Calorimeter Level Trigger is presented. The Zeus detector is being built for operation at HERA, a new storage ring that will provide collisions between 820 GeV protons and 30 GeV electrons in 1990. The calorimeter is made of depleted uranium plates and plastic scintillator read out by wavelength shifter bars into 12,864 photomultiplier tubes. These signals are combined into 974 trigger towers with separate electromagnetic and hadronic sums. The calorimeter first level trigger is pipelined with a decision provided 5 {mu}sec after each beam crossing, occurring every 96 nsec. The trigger determines the total energy, the total transverse energy, the missing energy, and the energy and number of isolated electrons and muons. It also provides information on the number and energy of clusters. The trigger rate needs to be held to 1 kHz against a rate of proton-beam gas interactions of approximately 500 kHz. The summed trigger tower pulseheights are digitized by flash ADC`s. The digital values are linearized, stored and used for sums and pattern tests.

  17. 100 Gbps PCI-Express readout for the LHCb upgrade

    NASA Astrophysics Data System (ADS)

    Durante, P.; Neufeld, N.; Schwemmer, R.; Balbi, G.; Marconi, U.

    2015-04-01

    We present a new data acquisition system under development for the next upgrade of the LHCb experiment at CERN. We focus in particular on the design of a new generation of readout boards, the PCIe40, and on the viability of PCI-Express as an interconnect technology for high speed readout. We show throughput measurements across the PCI-Express bus, on Altera Stratix 5 devices, using a DMA mechanism and different synchronization schemes between the FPGA and the readout unit. Finally we discuss hardware and software design considerations necessary to achieve a data throughput of 100 Gbps in the final readout board.

  18. Prospects for studying penguin decays in LHCb experiments

    SciTech Connect

    Barsuk, S. Ya. Pakhlova, G. V. Belyaev, I. M.

    2006-04-15

    Investigation of loop penguin decays of beauty hadrons seems promising in testing the predictions of the Standard Model of electroweak and strong interactions and in seeking new phenomena beyond the Standard Model. The possibility of studying the radiative penguin decays B{sup 0} {sup {yields}} K*{sup 0}{gamma}, B{sup 0}{sub s} {sup {yields}} {phi}{gamma}, and B{sup 0} {sup {yields}} {omega}{gamma} and the gluonic penguin decays B{sup 0} {sup {yields}} {phi}K{sup 0}{sub S} and B{sup 0}{sub s} {sup {yields}} {phi}{phi} in LHCb experiments is discussed.

  19. Measurements of the LHCb software stack on the ARM architecture

    NASA Astrophysics Data System (ADS)

    Vijay Kartik, S.; Couturier, Ben; Clemencic, Marco; Neufeld, Niko

    2014-06-01

    The ARM architecture is a power-efficient design that is used in most processors in mobile devices all around the world today since they provide reasonable compute performance per watt. The current LHCb software stack is designed (and thus expected) to build and run on machines with the x86/x86_64 architecture. This paper outlines the process of measuring the performance of the LHCb software stack on the ARM architecture - specifically, the ARMv7 architecture on Cortex-A9 processors from NVIDIA and on full-fledged ARM servers with chipsets from Calxeda - and makes comparisons with the performance on x86_64 architectures on the Intel Xeon L5520/X5650 and AMD Opteron 6272. The paper emphasises the aspects of performance per core with respect to the power drawn by the compute nodes for the given performance - this ensures a fair real-world comparison with much more 'powerful' Intel/AMD processors. The comparisons of these real workloads in the context of LHCb are also complemented with the standard synthetic benchmarks HEPSPEC and Coremark. The pitfalls and solutions for the non-trivial task of porting the source code to build for the ARMv7 instruction set are presented. The specific changes in the build process needed for ARM-specific portions of the software stack are described, to serve as pointers for further attempts taken up by other groups in this direction. Cases where architecture-specific tweaks at the assembler lever (both in ROOT and the LHCb software stack) were needed for a successful compile are detailed - these cases are good indicators of where/how the software stack as well as the build system can be made more portable and multi-arch friendly. The experience gained from the tasks described in this paper are intended to i) assist in making an informed choice about ARM-based server solutions as a feasible low-power alternative to the current compute nodes, and ii) revisit the software design and build system for portability and generic improvements.

  20. Measurement of the CP-violating phase γ at LHCb

    NASA Astrophysics Data System (ADS)

    Koopman, R. F.; LHCb Collaboration

    2016-07-01

    The CKM phase γ is the angle of the unitarity triangle which is least well known. To reach the highest sensitivity to its value, all currently available measurements using hadronic tree decays by LHCb are combined, resulting in γ=(73 ^{+9}_{-10})°. The combination includes results from measurements of time-integrated CP violation in B^{±}→ Dh^{±} and B0→ DK^{*0} decays, with h a pion or kaon, and from a time-dependent measurement of CP violation using Bs0→ Ds^{±}K^{∓} decays.

  1. Performance of CDF calorimeter simulation for Tevatron Run II

    SciTech Connect

    C. Currat

    2002-09-19

    The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.

  2. Test beam performance of the CDF plug upgrade hadron calorimeter

    SciTech Connect

    de Barbaro, P.; CDF Plug Upgrade Group

    1998-01-13

    We report on the performance of the CDF End Plug Hadron Calorimeter in a test beam. The sampling calorimeter is constructed using 2 inch iron absorber plates and scintillator planes with wavelength shifting fibers for readout. The linearity and energy resolution of the calorimeter response to pions, and the transverse uniformity of the response to muons and pions are presented. The parameter e/h, representing the ratio of the electromagnetic to hadronic response, is extracted from the data.

  3. Heat flow calorimeter. [measures output of Ni-Cd batteries

    NASA Technical Reports Server (NTRS)

    Fletcher, J. C.; Johnston, W. V. (Inventor)

    1974-01-01

    Heat flow calorimeter devices are used to measure heat liberated from or absorbed by an object. This device is capable of measuring the thermal output of sealed nickel-cadmium batteries or cells during charge-discharge cycles. An elongated metal heat conducting rod is coupled between the calorimeter vessel and a heat sink, thus providing the only heat exchange path from the calorimeter vessel itself.

  4. Monitors.

    ERIC Educational Resources Information Center

    Powell, David

    1984-01-01

    Provides guidelines for selecting a monitor to suit specific applications, explains the process by which graphics images are produced on a CRT monitor, and describes four types of flat-panel displays being used in the newest lap-sized portable computers. A comparison chart provides prices and specifications for over 80 monitors. (MBR)

  5. Test beam performance of CDF plug upgrade EM calorimeter

    SciTech Connect

    Fukui, Y.; CDF Upgrade Group

    1998-01-01

    CDF Plug Upgrade(tile-fiber) EM Calorimeter performed resolution of 15%/{radical}E{circle_plus}0.7% with non-linearity less than 1% in a energy range of 5-180 GeV at Fermilab Test Beam. Transverse uniformity of inside-tower-response of the EM Calorimeter was 2.2% with 56 GeV positron, which was reduced to 1.0% with response map correction. We observed 300 photo electron/GeV in the EM Calorimeter. Ratios of EM Calorimeter response to positron beam to that to {sup 137}Cs Source was stable within 1% in the period of 8 months.

  6. Performance of the SLD Warm Iron Calorimeter prototype

    SciTech Connect

    Callegari, G.; Piemontese, L.; De Sangro, R.; Peruzzi, I., Piccolo, M.; Busza, W.; Friedman, J.; Johnson, A.; Kendall, H.; Kistiakowsky, V.

    1986-03-01

    A prototype hadron calorimeter, of similar design to the Warm Iron Calorimeter (WIC) planned for the SLD experiment, has been built and its performance has been studied in a test beam. The WIC is an iron sampling calorimeter whose active elements are plastic streamer tubes similar to those used for the Mont-Blanc proton decay experiment. The construction and operation of the tubes will be briefly described together with their use in an iron calorimeter - muon tracker. Efficiency, resolution and linearity have been measured in a hadron/muon beam up to 11 GeV. The measured values correspond to the SLD design goals.

  7. CALET: a calorimeter for cosmic-ray measurements in space

    NASA Astrophysics Data System (ADS)

    Mori, Nicola

    2013-06-01

    The CALorimetric Electron Telescope (CALET) instrument is scheduled for a launch in 2014 and attached to the Exposed Facility of the Japanese Experimental Module (JEM-EF) on the International Space Station. Its main objective is to perform precise measurements of the electron+positron spectrum in cosmic rays at energies up to some TeV, searching for signals from dark matter and/or contributions from nearby astrophysical sources like pulsars. Other scientific goals include the investigation of heavy ions spectra up to Fe, elemental abundance of trans-iron nuclei and a measurement of the diffuse γ ray emission with high energy resolution. The instrument is now under construction, and consists of a charge detection device (CHD) composed of two layers of plastic scintillators, a finely-segmented sampling calorimeter (IMC) and a deep, homogeneous calorimeter (TASC) made of PbWO scintillating bars. The good containment of electromagnetic showers (total depth ˜3X0(IMC)+27X0(TASC)=30X0) together with the homogeneity of TASC give an energy resolution for electrons and γ rays about 2%. CHD can discriminate the charge of primary particles with a resolution between 15% and 30% up to Fe. The finely-segmented IMC, made by tungsten layers and 1mm-wide scintillating fibers, can provide detailed information about the start and early development of particle showers. Lateral and longitudinal shower-development information from TASC, together with informations from IMC, can be used to achieve an electron/proton rejection power about 105. High-statistics for collected data will be achieved by means of the planned 5-years exposure time together with a geometrical factor of 0.12 m sr. Furthermore, a Gamma-Ray Burst monitor will complement the main detector. In this paper the status of the mission, the design and expected performance of the instrument will be detailed.

  8. New mechanisms for double charmed meson production at the LHCb

    NASA Astrophysics Data System (ADS)

    Maciuła, Rafał; Saleev, Vladimir A.; Shipilova, Alexandra V.; Szczurek, Antoni

    2016-07-01

    We discuss production of D0D0 (and Dbar0Dbar0) pairs related to the LHCb Collaboration results for √{ s} = 7 TeV in proton-proton scattering. We consider double-parton scattering (DPS) mechanisms of double c c bar production and subsequent cc →D0D0 hadronization as well as double g and mixed gc c bar production with gg →D0D0 and gc →D0D0 hadronization calculated with the help of the scale-dependent hadronization functions of Kniehl et al. Single-parton scattering (SPS) mechanism of digluon production is also taken into account. We compare our results with several correlation observables in azimuthal angle φD0D0 between D0 mesons or in dimeson invariant mass MD0D0. The inclusion of new mechanisms with g →D0 fragmentation leads to larger cross sections, than when including only DPS mechanism cc →D0D0 with standard scale-independent fragmentation functions. Some consequences of the presence of the new mechanisms are discussed. In particular a larger σeff is needed to describe the LHCb data. There is a signature that σeff may depend on transverse momentum of c quarks and/or c bar antiquarks.

  9. VeloPix ASIC development for LHCb VELO upgrade

    NASA Astrophysics Data System (ADS)

    van Beuzekom, M.; Buytaert, J.; Campbell, M.; Collins, P.; Gromov, V.; Kluit, R.; Llopart, X.; Poikela, T.; Wyllie, K.; Zivkovic, V.

    2013-12-01

    The upgrade of the LHCb experiment, planned for 2018, will transform the readout of the entire experiment to a triggerless system operating at 40 MHz. All data reduction algorithms will be run in a high level software farm, and will have access to event information from all subdetectors. This approach will give great power and flexibility in accessing the physics channels of interest in the future, in particular the identification of flavour tagged events with displaced vertices. The data acquisition and front end electronics systems require significant modification to cope with the enormous throughput of data. For the silicon vertex locator (VELO) a dedicated development is underway for a new ASIC, VeloPix, which will be a derivative of the Timepix/Medipix family of chips. The chip will be radiation hard and be able to cope with pixel hit rates of above 500 MHz, highly non-uniformly distributed over the 2 cm2 chip area. The chip will incorporate local intelligence in the pixels for time-over-threshold measurements, time-stamping and sparse readout. It must in addition be low power, radiation hard, and immune to single event upsets. In order to cope with the datarates and use the pixel area most effectively, an on-chip data compression scheme will integrated. This paper will describe the requirements of the LHCb VELO upgrade, and give an overview of the digital architecture being developed specifically for the readout chip.

  10. More lepton flavor violating observables for LHCb's run 2

    NASA Astrophysics Data System (ADS)

    Guadagnoli, Diego; Melikhov, Dmitri; Reboud, Méril

    2016-09-01

    The RK measurement by LHCb suggests non-standard lepton non-universality (LNU) to occur in b → sℓ+ℓ- transitions, with effects in muons rather than electrons. A number of other measurements of b → sℓ+ℓ- transitions by LHCb and B-factories display disagreement with the SM predictions and, remarkably, these discrepancies are consistent in magnitude and sign with the RK effect. Non-standard LNU suggests non-standard lepton flavor violation (LFV) as well, for example in B → Kℓℓ‧ and Bs → ℓℓ‧. There are good reasons to expect that the new effects may be larger for generations closer to the third one. In this case, the Bs → μe decay may be the most difficult to reach experimentally. We propose and study in detail the radiative counterpart of this decay, namely Bs → μeγ, whereby the chiral-suppression factor is replaced by a factor of order α / π. A measurement of this mode would be sensitive to the same physics as the purely leptonic LFV decay and, depending on experimental efficiencies, it may be more accessible. A realistic expectation is a factor of two improvement in statistics for either of the Bd,s modes.

  11. The LHCb Data Acquisition and High Level Trigger Processing Architecture

    NASA Astrophysics Data System (ADS)

    Frank, M.; Gaspar, C.; Jost, B.; Neufeld, N.

    2015-12-01

    The LHCb experiment at the LHC accelerator at CERN collects collisions of particle bunches at 40 MHz. After a first level of hardware trigger with an output rate of 1 MHz, the physically interesting collisions are selected by running dedicated trigger algorithms in the High Level Trigger (HLT) computing farm. This farm consists of up to roughly 25000 CPU cores in roughly 1750 physical nodes each equipped with up to 4 TB local storage space. This work describes the LHCb online system with an emphasis on the developments implemented during the current long shutdown (LS1). We will elaborate the architecture to treble the available CPU power of the HLT farm and the technicalities to determine and verify precise calibration and alignment constants which are fed to the HLT event selection procedure. We will describe how the constants are fed into a two stage HLT event selection facility using extensively the local disk buffering capabilities on the worker nodes. With the installed disk buffers, the CPU resources can be used during periods of up to ten days without beams. These periods in the past accounted to more than 70% of the total time.

  12. Disk storage management for LHCb based on Data Popularity estimator

    NASA Astrophysics Data System (ADS)

    Hushchyn, Mikhail; Charpentier, Philippe; Ustyuzhanin, Andrey

    2015-12-01

    This paper presents an algorithm providing recommendations for optimizing the LHCb data storage. The LHCb data storage system is a hybrid system. All datasets are kept as archives on magnetic tapes. The most popular datasets are kept on disks. The algorithm takes the dataset usage history and metadata (size, type, configuration etc.) to generate a recommendation report. This article presents how we use machine learning algorithms to predict future data popularity. Using these predictions it is possible to estimate which datasets should be removed from disk. We use regression algorithms and time series analysis to find the optimal number of replicas for datasets that are kept on disk. Based on the data popularity and the number of replicas optimization, the algorithm minimizes a loss function to find the optimal data distribution. The loss function represents all requirements for data distribution in the data storage system. We demonstrate how our algorithm helps to save disk space and to reduce waiting times for jobs using this data.

  13. Absolute luminosity measurements with the LHCb detector at the LHC

    NASA Astrophysics Data System (ADS)

    LHCb Collaboration

    2012-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented.

  14. Performance of the Tile PreProcessor Demonstrator for the ATLAS Tile Calorimeter Phase II Upgrade

    NASA Astrophysics Data System (ADS)

    Carrió, F.; Moreno, P.; Valero, A.

    2016-03-01

    The Tile Calorimeter PreProcessor demonstrator is a high performance double AMC board based on FPGA resources and QSFP modules. This board has been designed in the framework of the ATLAS Tile Calorimeter Demonstrator project for the Phase II Upgrade as the first stage of the back-end electronics. The TilePPr demonstrator has been conceived to receive and process the data coming from the front-end electronics of the TileCal Demonstrator module, as well as to configure it. Moreover, the TilePPr demonstrator handles the communication with the Detector Control System to monitor and control the front-end electronics. The TilePPr demonstrator represents 1/8 of the final TilePPr that will be designed and installed into the detector for the ATLAS Phase II Upgrade.

  15. Summary talk on fiber tower calorimeter for the scintillation calorimeter subgroups

    SciTech Connect

    White, A.P.; Walker, J.K.; Johnson, C.; Wahl, H.; Gabriel, T.

    1989-01-01

    We present here a new calorimeter design based on small scintillator tiles, lead absorber and wavelength shifting fiber readout. We have addressed all the major issues in SSC calorimetry and have developed a design with many advantageous features. It has been well demonstrated that the best resolution is obtained for a 'compensated' calorimeter. It is also well known how such compensation may be achieved by a suitable choice of active and passive materials and their relative thickness. One such choice is that of lead and scintillator for which the best thickness ratio is 4:1. This selection has been used in the development of the so-called spaghetti calorimeter (SPACAL) discussed at this workshop. The relative merits of this and many other designs have been the subject of much discussion at SSC workshops from which a number of critical issues have emerged for each design. In the present paper, we have addressed the issues raised in the SPACAL design and proposed an alternative, improved design. The SPACAL represents a significant step forward in calorimeter design, but there are always areas which can be improved in any design when it is subjected to detailed study. Specifically we have considered the areas of energy resolution, channeling, projective towers/calibration, longitudinal segmentation, and radiation sensitivity. We will now discuss each of these areas in turn. 5 refs., 9 figs.

  16. T-1018 UCLA Spacordion Tungsten Powder Calorimeter

    SciTech Connect

    Trentalange, Stephen; Tsai, Oleg; Igo, George; Huang, Huan; Pan, Yu Xi; Dunkelberger, Jay; Xu, Wen Qin; Soha, Aria; Heppelmann, Steven; Gagliardi, Carl; /Texas A-M

    2011-11-16

    The present experiments at the BNL-RHIC facility are evolving towards physics goals which require the detection of medium energy electromagnetic particles (photons, electrons, neutral pions, eta mesons, etc.), especially at forward angles. New detectors will place increasing demands on energy resolution, hadron rejection and two-photon resolution and will require large area, high performance electromagnetic calorimeters in a variety of geometries. In the immediate future, either RHIC or JLAB will propose a facility upgrade (Electron-Ion Collider, or EIC) with physics goals such as electron-heavy ion collisions (or p-A collisions) with a wide range of calorimeter requirements. An R and D program based at Brookhaven National Laboratory has awarded the group funding of approximately $110,000 to develop new types of calorimeters for EIC experiments. The UCLA group is developing a method to manufacture very flexible and cost-effective, yet high quality calorimeters based on scintillating fibers and tungsten powder. The design and features of the calorimeter can be briefly stated as follows: an arbitrarily large number of small diameter fibers (< 0.5 mm) are assembled as a matrix and held rigidly in place by a set of precision screens inside an empty container. The container is then back-filled with tungsten powder, compacted on a vibrating table and infused with epoxy under vacuum. The container is then removed. The resulting sub-modules are extremely uniform and achieve roughly the density of pure Lead. The sub-modules are stacked together to achieve a final detector of the desired shape. There is no dead space between sub-modules and the fibers can be in an accordion geometry bent to prevent 'channeling' of the particles due to accidental alignment of their track with the module axis. This technology has the advantage of being modular and inexpensive to the point where the construction work may be divided among groups the size of typical university physics departments

  17. Shashlik calorimeter response to high energy electrons

    NASA Astrophysics Data System (ADS)

    Dobrzynski, L.

    1994-04-01

    We report the results coming from an extensive study of a Shashlik calorimeter prototype for CMS. Nine (47 × 47 mm 2) towers were exposed to a high energy electron beam at CERN SPS and read out by silicon photodiodes followed by low noise preamplifiers. The main results are the measurements of: -|the energy resolution: {σ}/{E}(%)= {(8.4±0.1)}/{E}⊕ {(0.37±0.03)}/{E}⊕(0.8±0.2) ; -|the shower resolution: σ x,y(mm)= {9.1±0.3 stat±0.7 syst}/{E}⊕ {27±1.4 stat±2.1 syst}/{E}. -|We also give the angular resolution of the direction of an electron shower. It is estimated by using one point from a preshower detector located at 3 X0 and the second point on a barycenter in the calorimeter mosaic. The result is encouraging being in agreement with a resolution of σ θ( mrad) = {70}/{√E}, which gives for an electron of 50 GeV an angular resolution of 10 mrad. -|The uniformity of the calorimeter response is found to be better than ± 1%. -|The mean light yield measured in Shashlik towers equipped with Y7 WLS fibres from Kuraray and aluminized at the front side of the tower is of the order of 12300 γ/ GeV assuming a quantum efficiency of 62.5% for the Si photodiode.

  18. Calorimeter measurements of low wattage items

    SciTech Connect

    Cremers, T.L.; Camp, K.L.; Hildner, S.S.; Sedlacek, W.A.

    1993-08-01

    The transition of DOE facilities from production to decontamination and decommissioning has led to more measurements of waste, scrap, and other less attractive materials. The difficulty that these materials pose for segmented gamma scanning and neutron counting has increased the use of calorimetric assay for very low wattage items (< 250 millwatts). We have measured well characterized {sup 238}Pu oxide ranging in wattage from 25 to 500 milliwatts in the calorimeters at the Los Alamos Plutonium Facility and report the error and the precision of the measurements.

  19. Ac loss calorimeter for three-phase cable

    SciTech Connect

    Daney, D.E.; Boenig, H.J.; Maley, M.P.; McMurry, D.E.; DeBlanc, B.G.

    1996-10-01

    A calorimeter for measuring ac losses in meter-long lengths of HTS superconducting power transmission line cables is described. The calorimeter, which is based on a temperature difference technique, has a precision of 1 mW and measures single, two-phase (coupling), and three-phase losses. The measurements show significant coupling losses between phases.

  20. The ATLAS Liquid Argon Calorimeter: Construction, Integration, Commissioning

    SciTech Connect

    Aleksa, Martin

    2006-10-27

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

  1. First results with charmless two-body B-decays at LHCb, and future prospects

    ScienceCinema

    None

    2011-04-25

    LHCb is an experiment which is designed to perform flavour physics measurements at the LHC. Charged two-body charmless B decays (e.g. B^0 -> Kpi, pipi, B_s->KK, etc) receive significant contributions from loop diagrams and are thus sensitive probes of New Physics. Study of these modes is therefore an important physics goal of LHCb. First results will be presented, using around 37 pb^{-1} of data collected at \\sqrt{s}=7 TeV in 2010. These results illustrate the power of the LHCb trigger system and particle identification capabilities of the RICH detectors in isolating clean samples of each final state, and include preliminary measurements of direct CP-violation in certain key modes. The prospects for these measurements in the coming run will be presented. A brief survey will also be given of results and prospect in other areas of the LHCb physics programme.

  2. First results with charmless two-body B-decays at LHCb, and future prospects

    SciTech Connect

    2011-02-22

    LHCb is an experiment which is designed to perform flavour physics measurements at the LHC. Charged two-body charmless B decays (e.g. B^0 -> Kpi, pipi, B_s->KK, etc) receive significant contributions from loop diagrams and are thus sensitive probes of New Physics. Study of these modes is therefore an important physics goal of LHCb. First results will be presented, using around 37 pb^{-1} of data collected at \\sqrt{s}=7 TeV in 2010. These results illustrate the power of the LHCb trigger system and particle identification capabilities of the RICH detectors in isolating clean samples of each final state, and include preliminary measurements of direct CP-violation in certain key modes. The prospects for these measurements in the coming run will be presented. A brief survey will also be given of results and prospect in other areas of the LHCb physics programme.

  3. Electromagnetic and Hadron Calorimeters in the MIPP Experiment

    SciTech Connect

    T. S. Nigmanov; H. R. Gustafson; M. J. Longo; D. Rajaram

    2006-10-01

    The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons, and nucleons produced in π, K, and p interactions on various targets using beams from the Main Injector at Fermilab. The purpose of the calorimeters is to measure the production of forward-going photons and neutrons. The electromagnetic calorimeter consists of 10 lead plates interspersed with proportional chambers followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. We collected data with a variety of targets with beam energies from 5 GeV/c up to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons and protons is discussed. The performance of the calorimeters was tested on a neutron sample.

  4. Electromagnetic and Hadron Calorimeters in the MIPP Experiment

    SciTech Connect

    Nigmanov, T. S.; Gustafson, H. R.; Longo, M. J.; Rajaram, D.

    2006-10-27

    The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons, and nucleons produced in {pi}, K, and p interactions on various targets using beams from the Main Injector at Fermilab. The purpose of the calorimeters is to measure the production of forward-going photons and neutrons. The electromagnetic calorimeter consists of 10 lead plates interspersed with proportional chambers followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. We collected data with a variety of targets with beam energies from 5 GeV/c up to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons and protons is discussed. The performance of the calorimeters was tested on a neutron sample.

  5. Electromagnetic and hadron calorimeters in the MIPP experiment

    SciTech Connect

    Nigmanov, T.S.; Gustafson, H.R.; Longo, M.J.; Park, H.K.; Rajaram, D.; Dukes, C.; Lu, L.C.; Materniak, C.; Nelson, K.; Norman, A.; Meyer, H.; /Fermilab /Harvard U. /Indiana U. /Iowa U. /Purdue U.

    2008-10-01

    The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons, and nucleons in {pi}, K, and p interactions on various targets using beams from the Main Injector at Fermilab. The function of the calorimeters is to measure the production of forward-going neutrons and photons. The electromagnetic calorimeter consists of 10 lead plates interspersed with proportional chambers. It was followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. The data presented were collected with a variety of targets and beam momenta from 5 to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons, and protons is discussed. The resolution for electrons was found to be 0.27/{radical}E, and for hadrons the resolution was 0.554/{radical}E with a constant term of 2.6%. The performance of the calorimeters was tested on a neutron sample.

  6. Electromagnetic and Hadron Calorimeters in the MIPP Experiment

    SciTech Connect

    T. S. Nigmanov; H. R. Gustafson; M. J. Longo; H. K. Park; D. Rajaram; and 13 others

    2008-10-15

    The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons, and nucleons in π, K, and p interactions on various targets using beams from the Main Injector at Fermilab. The function of the calorimeters is to measure the production of forward-going neutrons and photons. The electromagnetic calorimeter consists of 10 lead plates interspersed with proportional chambers. It was followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. The data presented were collected with a variety of targets and beam momenta from 5 GeV/c to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons, and protons is discussed. The resolution for electrons was found to be 0.27/sqrt(E), and for hadrons the resolution was 0.554/sqrt(E) with a constant term of 2.6%. The performance of the calorimeters was tested on a neutron sample.

  7. Development of a forward calorimeter system for the STAR experiment

    NASA Astrophysics Data System (ADS)

    Tsai, O. D.; Aschenauer, E.; Christie, W.; Dunkelberger, L. E.; Fazio, S.; Gagliardi, C. A.; Heppelmann, S.; Huang, H. Z.; Jacobs, W. W.; Igo, G.; Kisilev, A.; Landry, K.; Liu, X.; Mondal, M. M.; Pan, Y. X.; Sergeeva, M.; Shah, N.; Sichtermann, E.; Trentalange, S.; Visser, G.; Wissink, S.

    2015-02-01

    We present results of an R&D program to develop a forward calorimeter system (FCS) for the STAR experiment at the Relativistic Heavy Ion Collider at BNL. The FCS is a very compact, compensated, finely granulated, high resolution calorimeter system being developed for p+p and p+A program at RHIC. The FCS prototype consists of both electromagnetic and hadron calorimeters. The electromagnetic portion of the detector is constructed with W powder and scintillation fibers. The hadronic calorimeter is a traditional Pb/Sc-plate sandwich design. Both calorimeters were readout with Hamamatsu MPPCs. A full- scale prototype of the FCS was tested with a beam at FNAL in March 2014. We present details of the design, construction technique and performance of the FCS prototype during the test run at FNAL.

  8. Charge Detector for the Imaging Calorimeter for ACCESS (ICA)

    NASA Technical Reports Server (NTRS)

    Lee, Jeongin; Adams, J. H., Jr.

    2000-01-01

    NASA's Advanced Cosmic Ray Experiment for the Space Station (ACCESS) Mission is planned to consist of a transition radiation detector (TRD) and a thin ionization calorimeter. In order to measure the charge of the primary cosmic ray, it is necessary for the calorimeter to have its own charge detector. Silicon detectors are chosen for the charge detector because of their excellent resolution, small size and nearly square shape. Monte Carlo simulations are performed to find the probability of misidentifying protons as alpha particles due to backscattered radiation from the calorimeter. Simulations were also used to investigate identifying primary cosmic rays that fragmented in the TRD before reaching the calorimeter. For this study algorithms have been developed for determining a direction of the core shower in the calorimeter. These algorithms are used to find the approximate location of the primary particle in the silicon detectors. Results show the probability to misidentify the charge depends upon the energy and direction of the primary particles.

  9. Closed Gap Slug Calorimeter for Plasma Stream Characterization

    NASA Technical Reports Server (NTRS)

    Nawaz, Anuscheh; Gorbunov, Sergey; Terrazas-Salinas, Imelda; Jones, Steven M.

    2012-01-01

    Slug calorimeters are used in sheer and stagnation mode to characterize heat flux levels for high enthalpy streams. The traditional design features a gap between slug and holder, which can be of concern in these convective heat flux environments. The challenge is to develop a calorimeter that closes the gap to gas flow, but largely maintains thermal insulation of the slug. The work presented herein introduces two new slug calorimeter designs featuring a closed gap. This is done using either aerogel as a filler or press fitting the slug with a disk. The designs were verified and compared to the baseline calorimeter design under radiative heat flux. Building on this, the calorimeters were exposed to convective heat flux in the arc-jet facilities. Results from the new designs and conclusions on the impact of the gap in convective heat flux will be shown.

  10. The GlueX Barrel Electromagnetic Calorimeter

    NASA Astrophysics Data System (ADS)

    Papandreou, Zisis; Lolos, George; Semenov, Andrei; GlueX Collaboration

    2011-04-01

    The goal of the GLUEX experiment at Jefferson Lab is to search for exotic hybrid mesons as evidence of gluonic excitations, in an effort to understand confinement in QCD. A key subsystem of the GLUEX detector is the electromagnetic barrel calorimeter (BCAL) located inside a 2-Tesla superconducting solenoid. BCAL is a ``spaghetti calorimeter,'' consisting of layers of corrugated lead sheets, interleaved with planes of 1-mm-diameter, double-clad, Kuraray SCSF-78MJ scintillating fibres, bonded in the lead grooves using optical epoxy. The detector will consist of 48 modules and will be readout using nearly 4,000 large-area (1.26 cm2 each) silicon photomultiplier arrays. BCAL construction is well under way at the University of Regina and test results will be shown. Supported by NSERC grant SAPJ-326516, DOE grant DE-FG02-0SER41374 and Jefferson Science Associates, LLC. under U.S. DOE Contract No. DE-AC05-06OR23177.

  11. Polarization effects in double open-charm production at LHCb

    NASA Astrophysics Data System (ADS)

    Echevarría, Miguel G.; Kasemets, Tomas; Mulders, Piet J.; Pisano, Cristian

    2015-04-01

    Double open-charm production is one of the most promising channels to disentangle single from double parton scattering (DPS) and study different properties of DPS. Several studies of the DPS contributions have been made. A missing ingredient so far has been the study of polarization effects, arising from spin correlations between the two partons inside an unpolarized proton. We investigate the impact polarization has on the double open-charm cross section. We show that the longitudinally polarized gluons can give significant contributions to the cross section, but for most of the considered kinematic region only have a moderate effect on the shape. We compare our findings to the LHCb data in the D 0 D 0 final state, identify observables where polarization does have an impact on the distribution of the final state particles, and suggest measurements which could lead to first experimental indications of, or limits on, polarization in DPS.

  12. Central Exclusive Production in pp collisions at LHCb

    NASA Astrophysics Data System (ADS)

    McNulty, Ronan

    2016-03-01

    Central Exclusive Production (CEP) is a unique process at hadron machines in which particles are produced via colourless propagators, and several measurements at the LHC are directly comparable with past and future electron-ion colliders. LHCb have measured the cross-sections for the CEP of vector mesons, J/ψ,ψ (2S),ϒ(1S), ϒ(2S) and ϒ(3S), which are photo-produced. In the double Pomeron exchange process, preliminary measurements have been made of χc0, χc1, χc2 meson production while the first observations of the CEP of pairs of charmonia, J/ψJ/ψ and J/ψψ (2S), have been made and limits obtained on the pair production of other charmonia.

  13. Identification of beauty and charm quark jets at LHCb

    NASA Astrophysics Data System (ADS)

    The LHCb Collaboration

    2015-06-01

    Identification of jets originating from beauty and charm quarks is important for measuring Standard Model processes and for searching for new physics. The performance of algorithms developed to select b- and c-quark jets is measured using data recorded by LHCb from proton-proton collisions at √s = 7 TeV in 2011 and at √s = 8 TeV in 2012. The efficiency for identifying a b(c) jet is about 65%(25%) with a probability for misidentifying a light-parton jet of 0.3% for jets with transverse momentum pT > 20GeV and pseudorapidity 2.2 < η < 4.2. The dependence of the performance on the pT and η of the jet is also measured.

  14. A History-based Estimation for LHCb job requirements

    NASA Astrophysics Data System (ADS)

    Rauschmayr, Nathalie

    2015-12-01

    The main goal of a Workload Management System (WMS) is to find and allocate resources for the given tasks. The more and better job information the WMS receives, the easier will be to accomplish its task, which directly translates into higher utilization of resources. Traditionally, the information associated with each job, like expected runtime, is defined beforehand by the Production Manager in best case and fixed arbitrary values by default. In the case of LHCb's Workload Management System no mechanisms are provided which automate the estimation of job requirements. As a result, much more CPU time is normally requested than actually needed. Particularly, in the context of multicore jobs this presents a major problem, since single- and multicore jobs shall share the same resources. Consequently, grid sites need to rely on estimations given by the VOs in order to not decrease the utilization of their worker nodes when making multicore job slots available. The main reason for going to multicore jobs is the reduction of the overall memory footprint. Therefore, it also needs to be studied how memory consumption of jobs can be estimated. A detailed workload analysis of past LHCb jobs is presented. It includes a study of job features and their correlation with runtime and memory consumption. Following the features, a supervised learning algorithm is developed based on a history based prediction. The aim is to learn over time how jobs’ runtime and memory evolve influenced due to changes in experiment conditions and software versions. It will be shown that estimation can be notably improved if experiment conditions are taken into account.

  15. An automated flow calorimeter for heat capacity and enthalpy measurements at elevated temperatures and pressures

    SciTech Connect

    Yesavage, V.F.

    1990-08-31

    The need for highly accurate thermal property data for a broad range of new application fluids is well documented. To facilitate expansion of the current thermophysical database, an automated flow calorimeter was developed for the measurement of highly accurate isobaric heat capacities and enthalpies of fluids at elevated temperatures and pressures. The experimental technique utilizes traditional electrical power input, adiabatic flow calorimetry with a precision metering pump that eliminates the need for on-line flow rate monitoring. In addition, a complete automation system, greatly simplifies the operation of the apparatus and increases the rapidity of the measurement process. The range over which the instrument was tested, was 300--600 K and 0--12 Mpa, although the calorimeter should perform up to the original design goals of 700 K and 30 MPa. The new flow calorimeter was evaluated by measuring the mean, isobaric, specific heat capacities of liquid water and n-pentane. These experiments yielded an average deviation from the standard literature data of +0.02% and a total variation of 0.05%. Additional data analysis indicated that the overall measurement uncertainty was conservatively estimated as 0.2% with an anticipated precision of 0.1--0.15% at all operating conditions. 44 refs., 27 figs., 2 tabs.

  16. An automated flow calorimeter for heat capacity and enthalpy measurements at elevated temperatures and pressures

    NASA Astrophysics Data System (ADS)

    Yesavage, Victor F.

    1990-08-01

    The need for highly accurate thermal property data for a broad range of new application fluids is well documented. To facilitate expansion of the current thermophysical database, an automated flow calorimeter was developed for the measurement of highly accurate isobaric heat capacities and enthalpies of fluids at elevated temperatures and pressures. The experimental technique utilizes traditional electrical power input, adiabatic flow calorimetry with a precision metering pump that eliminates the need for on-line flow rate monitoring. In addition, a complete automation system greatly simplifies the operation of the apparatus and increases the rapidity of the measurement process. The range over which the instrument was tested was 300 to 600 K and 0 to 12 Mpa, although the calorimeter should perform up to the original design goals of 700 K and 30 MPa. The new flow calorimeter was evaluated by measuring the mean, isobaric, specific heat capacities of liquid water and n-pentane. These experiments yielded an average deviation from the standard literature data of +0.02 percent and a total variation of 0.05 percent. Additional data analysis indicated that the overall measurement uncertainty was conservatively estimated as 0.2 percent with an anticipated precision of 0.1 to 0.15 percent at all operating conditions.

  17. Arabidopsis Mutants Deleted in the Light-Harvesting Protein Lhcb4 Have a Disrupted Photosystem II Macrostructure and Are Defective in Photoprotection[C][W

    PubMed Central

    de Bianchi, Silvia; Betterle, Nico; Kouril, Roman; Cazzaniga, Stefano; Boekema, Egbert; Bassi, Roberto; Dall’Osto, Luca

    2011-01-01

    The role of the light-harvesting complex Lhcb4 (CP29) in photosynthesis was investigated in Arabidopsis thaliana by characterizing knockout lines for each of the three Lhcb4 isoforms (Lhcb4.1/4.2/4.3). Plants lacking all isoforms (koLhcb4) showed a compensatory increase of Lhcb1 and a slightly reduced photosystem II/I ratio with respect to the wild type. The absence of Lhcb4 did not result in alteration in electron transport rates. However, the kinetic of state transition was faster in the mutant, and nonphotochemical quenching activity was lower in koLhcb4 plants with respect to either wild type or mutants retaining a single Lhcb4 isoform. KoLhcb4 plants were more sensitive to photoinhibition, while this effect was not observed in knockout lines for any other photosystem II antenna subunit. Ultrastructural analysis of thylakoid grana membranes showed a lower density of photosystem II complexes in koLhcb4. Moreover, analysis of isolated supercomplexes showed a different overall shape of the C2S2 particles due to a different binding mode of the S-trimer to the core complex. An empty space was observed within the photosystem II supercomplex at the Lhcb4 position, implying that the missing Lhcb4 was not replaced by other Lhc subunits. This suggests that Lhcb4 is unique among photosystem II antenna proteins and determinant for photosystem II macro-organization and photoprotection. PMID:21803939

  18. Arabidopsis mutants deleted in the light-harvesting protein Lhcb4 have a disrupted photosystem II macrostructure and are defective in photoprotection.

    PubMed

    de Bianchi, Silvia; Betterle, Nico; Kouril, Roman; Cazzaniga, Stefano; Boekema, Egbert; Bassi, Roberto; Dall'Osto, Luca

    2011-07-01

    The role of the light-harvesting complex Lhcb4 (CP29) in photosynthesis was investigated in Arabidopsis thaliana by characterizing knockout lines for each of the three Lhcb4 isoforms (Lhcb4.1/4.2/4.3). Plants lacking all isoforms (koLhcb4) showed a compensatory increase of Lhcb1 and a slightly reduced photosystem II/I ratio with respect to the wild type. The absence of Lhcb4 did not result in alteration in electron transport rates. However, the kinetic of state transition was faster in the mutant, and nonphotochemical quenching activity was lower in koLhcb4 plants with respect to either wild type or mutants retaining a single Lhcb4 isoform. KoLhcb4 plants were more sensitive to photoinhibition, while this effect was not observed in knockout lines for any other photosystem II antenna subunit. Ultrastructural analysis of thylakoid grana membranes showed a lower density of photosystem II complexes in koLhcb4. Moreover, analysis of isolated supercomplexes showed a different overall shape of the C₂S₂ particles due to a different binding mode of the S-trimer to the core complex. An empty space was observed within the photosystem II supercomplex at the Lhcb4 position, implying that the missing Lhcb4 was not replaced by other Lhc subunits. This suggests that Lhcb4 is unique among photosystem II antenna proteins and determinant for photosystem II macro-organization and photoprotection. PMID:21803939

  19. High-sensitivity microfluidic calorimeters for biological and chemical applications

    PubMed Central

    Lee, Wonhee; Fon, Warren; Axelrod, Blake W.; Roukes, Michael L.

    2009-01-01

    High-sensitivity microfluidic calorimeters raise the prospect of achieving high-throughput biochemical measurements with minimal sample consumption. However, it has been challenging to realize microchip-based calorimeters possessing both high sensitivity and precise sample-manipulation capabilities. Here, we report chip-based microfluidic calorimeters capable of characterizing the heat of reaction of 3.5-nL samples with 4.2-nW resolution. Our approach, based on a combination of hard- and soft-polymer microfluidics, provides both exceptional thermal response and the physical strength necessary to construct high-sensitivity calorimeters that can be scaled to automated, highly multiplexed array architectures. Polydimethylsiloxane microfluidic valves and pumps are interfaced to parylene channels and reaction chambers to automate the injection of analyte at 1 nL and below. We attained excellent thermal resolution via on-chip vacuum encapsulation, which provides unprecedented thermal isolation of the minute microfluidic reaction chambers. We demonstrate performance of these calorimeters by resolving measurements of the heat of reaction of urea hydrolysis and the enthalpy of mixing of water with methanol. The device structure can be adapted easily to enable a wide variety of other standard calorimeter operations; one example, a flow calorimeter, is described. PMID:19706406

  20. Monitoring

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore

    2004-11-23

    The invention provides apparatus and methods which facilitate movement of an instrument relative to an item or location being monitored and/or the item or location relative to the instrument, whilst successfully excluding extraneous ions from the detection location. Thus, ions generated by emissions from the item or location can successfully be monitored during movement. The technique employs sealing to exclude such ions, for instance, through an electro-field which attracts and discharges the ions prior to their entering the detecting location and/or using a magnetic field configured to repel the ions away from the detecting location.

  1. Method and system for improved resolution of a compensated calorimeter detector

    DOEpatents

    Dawson, John W.

    1991-01-01

    An improved method and system for a depleted uranium calorimeter detector used in high energy physics experiments. In a depleted uranium calorimeter detector, the energy of a particle entering the calorimeter detector is determined and the output response of the calorimeter detector is compensated so that the ratio of the integrated response of the calorimeter detector from a lepton to the integrated response of the calorimeter detector from a hadron of the same energy as the lepton is approximately equal to 1. In the present invention, the energy of a particle entering the calorimeter detector is determined as a function of time and the hadron content of the response of the calorimeter detector is inferred based upon the time structure of the energy pulse measured by the calorimeter detector. The energy measurement can be corrected based on the inference of the hadron content whereby the resolution of the calorimeter can be improved.

  2. Radioactively induced noise in gas-sampling uranium calorimeters

    SciTech Connect

    Gordon, H.A.; Rehak, P.

    1982-01-01

    The signal induced by radioactivity of a U/sup 238/ absorber in a cell of a gas-sampling uranium calorimeter was studied. By means of Campbell's theorem, the levels of the radioactively induced noise in uranium gas-sampling calorimeters was calculated. It was shown that in order to obtain similar radioactive noise performance as U-liquid argon or U-scintillator combinations, the ..cap alpha..-particles from the uranium must be stopped before entering the sensing volume of gas-uranium calorimeters.

  3. Data Analysis for the Scintillating Optical Fiber Calorimeter (SOFCAL)

    NASA Technical Reports Server (NTRS)

    Christl, Mark J.

    1997-01-01

    The scintillating optical fiber calorimeter is a hybrid instrument with both active and passive components for measuring the proton and helium cosmic ray spectra from 0.2 to IO TeV kinetic energy. A thin emulsion/x-ray film chamber is situated between a cerenkov counter and an imaging calorimeter. Scintillating optical fibers sample the electromagnetic showers that develop in the calorimeter and identify the trajectory of cosmic rays that interact in SOFCAL. The emulsion/x-ray film data provide an in flight calibration for SOFCAL. The data reduction techniques used will be discussed and interim results of the analysis from a 20 hour balloon flight will be presented.

  4. D0 Silicon Upgrade: End Calorimeter Transfer Bridge Modification

    SciTech Connect

    Stredde, H.J.; /Fermilab

    1996-07-10

    During the assembly of major components into the D0 Detector, a transfer bridge was required to move the North-End Calorimeter from the clean room,over the cable bridge and onto the north sidewalk of the assembly hall. This experiment is now at the beginning stages of the next phase, namely the upgrade of this Detector for future physics research. A major piece of this upgrade is the installation of a solenoid magnet into the Central Calorimeter. In order to accomplish this, the South End Calorimeter has to be removed from the detector and the North End Calorimeter must be moved an additional 20-inch from its nominal open position (total 60-inch movement). The South End Calorimeter will be removed from the detector using the equipment designed for its installation. The calorimeter will be staged on the south sidewalk during the installation of the solenoid magnet and the central tracking systems. The North End Calorimeter is moved 60-inch to give more space between calorimeters during magnet, tracker and cable installation work. This movement will allow the calorimeter to remain coupled to the cryo system. However, this movement requires an extension be added to the center beam. This extension will support the rear wheels of the calorimeter and in the case of the end calorimeters, carry the majority of the weight. The extension is to be a modification of the transfer bridge. This modification, basically has T1 steel blocks added to one end and legs to the sidewalk supports at the other. The T1 steel blocks are notched to fit into the center beam porches and are welded to bridge rails. This design is the same as that for the installation bridge (3740.312-ME-273456), including the welds and weld procedures which are identical in both cases. Since load testing is impractical, the critical welds will be non-destructive tested by ultrasonic means. The laboratory, through the FESS Department, has a contract with M.Q.S. Inspection Inc. The results of this testing will be

  5. New tools for the simulation and design of calorimeters

    SciTech Connect

    Womersley, W.J.

    1989-07-10

    Two new approaches to the simulation and design of large hermetic calorimeters are presented. Firstly, the Shower Library scheme used in the fast generation of showers in the Monte Carlo of the calorimeter for the D-Zero experiment at the Fermilab Tevatron is described. Secondly, a tool for the design future calorimeters is described, which can be integrated with a computer aided design system to give engineering designers an immediate idea of the relative physics capabilities of different geometries. 9 refs., 6 figs., 1 tab.

  6. D0-EC RTD Wiring Layout (North Calorimeter)

    SciTech Connect

    Primdahl, K.; /Fermilab

    1991-06-04

    The temperature of the North End-Calorimeter of the D-Zero detector is to be monitored by several RTD temperature sensors. The location and other important information pertaining to each individual RTD is included in the following tables, which are grouped by bundle number. There are mne 60 pIll port connectors. Each connector corresponds to a bundle of twisted pairs. Twisted pairs, of one of eight colors along with either a black or white wire, run to 10-pin connectors which have a mate on the module or cryostat wall. In general, all 60 pins, or all 10 pins are not used. The color scheme of the wires was designed so that all the twisted pairs with white run West from the instrumentation port, and twisted pairs with black run East. This scheme proved to be very successful and efficient during the installation process. After being installed, every RTD connection was checked and their corresponding resistances were recorded by Jerry Blazey. All the RTD's tested successfully, except for 2. The 2 dead RTD's were: Channel 17 on bundle 4, which is located on the front of MH module 8L; and Channel 13 on bundle 5, which is located on the Bottom of the Middle Coarse Plate of the IH.

  7. Development of cryogenic alpha spectrometers using metallic magnetic calorimeters

    NASA Astrophysics Data System (ADS)

    Ranitzsch, P. C.; Kempf, S.; Pabinger, A.; Pies, C.; Porst, J.-P.; Schäfer, S.; Fleischmann, A.; Gastaldo, L.; Enss, C.; Jang, Y. S.; Kim, I. H.; Kim, M. S.; Kim, Y. H.; Lee, J. S.; Lee, K. B.; Lee, M. K.; Lee, S. J.; Yoon, W. S.; Yuryev, Y. N.

    2011-10-01

    Cryogenic particle detectors have recently been adopted in radiation detection and measurement because of their high energy resolution. Many of these detectors have demonstrated energy resolutions better than the theoretical limit of semiconductor detectors. We report the development of a micro-fabricated magnetic calorimeter coupled to a large-area particle absorber. It is based on a planar, 1 mm 2 large paramagnetic temperature sensor made of sputtered Au:Er, which covers a superconducting meander-shaped pickup coil coupled to a low-noise dc-SQUID to monitor the magnetization of the sensor. A piece of gold foil of 2.5×2.5×0.07 mm 3 was glued to the Au:Er film to serve as an absorber for incident alpha particles. The detector performance was investigated with an 241Am source. The signal size comparison for alpha and gamma peaks with a large difference in energy demonstrated that the detector had good linear behavior. An energy resolution of 2.83±0.05 keV in FWHM was obtained for 5.5 MeV alpha particles.

  8. Trigger circuits for the PHENIX electromagnetic calorimeter

    SciTech Connect

    Frank, S.S.; Britton, C.L. Jr.; Winterberg, A.L.; Young, G.R.

    1997-11-01

    Monolithic and discrete circuits have been developed to provide trigger signals for the PHENIX electromagnetic calorimeter detector. These trigger circuits are deadtimeless and create overlapping 4 by 4 energy sums, a cosmic muon trigger, and a 144 channel energy sum. The front end electronics of the PHENIX system sample the energy and timing channels at each bunch crossing (BC) but it is not known immediately if this data is of interest. The information from the trigger circuits is used to determine if the data collected is of interest and should be digitized and stored or discarded. This paper presents details of the design, issues affecting circuit performance, characterization of prototypes fabricated in 1.2 {micro}m Orbit CMOS, and integration of the circuits into the EMCal electronics system.

  9. Calorimeter Simulation with Hadrons in CMS

    SciTech Connect

    Piperov, Stefan; /Sofiya, Inst. Nucl. Res. /Fermilab

    2008-11-01

    CMS is using Geant4 to simulate the detector setup for the forthcoming data from the LHC. Validation of physics processes inside Geant4 is a major concern in view of getting a proper description of jets and missing energy for signal and background events. This is done by carrying out an extensive studies with test beam using the prototypes or real detector modules of the CMS calorimeter. These data are matched with Geant4 predictions using the same framework that is used for the entire CMS detector. Tuning of the Geant4 models is carried out and steps to be used in reproducing detector signals are defined in view of measurements of energy response, energy resolution, transverse and longitudinal shower profiles for a variety of hadron beams over a broad energy spectrum between 2 to 300 GeV/c. The tuned Monte Carlo predictions match many of these measurements within systematic uncertainties.

  10. A particle counting EM calorimeter using MAPS

    NASA Astrophysics Data System (ADS)

    Nooren, G.; Rocco, E.

    2015-02-01

    The availability of full size MAPS sensors makes it possible to construct a calorimeter with pixelsize of a few tens of micrometers. This would be small enough to count individual shower particles and would allow a shower shape analysis on an unprecedented, small scale. Interesting features would be tracking capability for particle flow algorithms and a superior discrimination of single photons from neutral and charged pions at high momenta. A small Molière radius together with high transverse resolution would allow to separate close showers, induced by photons from neutral pion decay. A full scale (4 RM, 28 X0) prototype was constructed to demonstrate this. It features 30 micron pixelsize and a longitudinal sampling at 1 radiation length. We will show results from beam tests of this prototype at electron energies of 2 to 200 GeV.