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Sample records for tevatron electron lenses

  1. Tevatron Electron Lenses: Design and Operation

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, Vladimir; /Fermilab; Bishofberger, Kip; /Los Alamos; Kamerdzhiev, Vsevolod; /Fermilab; Kozub, Sergei; /Serpukhov, IHEP; Kufer, Matthew; Kuznetsov, Gennady; Martinez, Alexander; Olson, Marvin; Pfeffer, Howard; Saewert, Greg; Scarpine, Vic; /Fermilab /SLAC /Fermilab /Serpukhov, IHEP /Novosibirsk, IYF /Serpukhov, IHEP /Fermilab

    2008-08-01

    The beam-beam effects have been the dominating sources of beam loss and lifetime limitations in the Tevatron proton-antiproton collider [1]. Electron lenses were originally proposed for compensation of electromagnetic long-range and head-on beam-beam interactions of proton and antiproton beams [2]. Results of successful employment of two electron lenses built and installed in the Tevatron are reported in [3,4,5]. In this paper we present design features of the Tevatron electron lenses (TELs), discuss the generation of electron beams, describe different modes of operation and outline the technical parameters of various subsystems.

  2. Tevatron Electron Lenses: Design and Operation

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, Vladimir; /Fermilab; Bishofberger, Kip; /Los Alamos; Kamerdzhiev, Vsevolod; /Fermilab; Kozub, Sergei; /Serpukhov, IHEP; Kufer, Matthew; Kuznetsov, Gennady; Martinez, Alexander; Olson, Marvin; Pfeffer, Howard; Saewert, Greg; Scarpine, Vic; /Fermilab; Seryi, Andrei; /SLAC; Solyak, Nikolai; /Fermilab; Sytnik, Veniamin; /Serpukhov, IHEP; Tiunov, Mikhail; /Novosibirsk, IYF; Tkachenko, Leonid; /Serpukhov, IHEP; Wildman, David; Wolff, Daniel; Zhang, Xiao-Long; /Fermilab

    2011-09-12

    Fermilab's Tevatron is currently the world's highest energy accelerator in which tightly focused beams of 980 GeV protons and antiprotons collide at two dedicated interaction points (IPs). Both beams share the same beam pipe and magnet aperture and, in order to avoid multiple detrimental head-on collisions, the beams are placed on separated orbits everywhere except the main IPs by using high-voltage (HV) electrostatic separators. The electromagnetic beam-beam interaction at the main IPs together with the long-range interactions between separated beams adversely affect the collider performance, reducing the luminosity integral per store (period of continuous collisions) by 10-30%. Tuning the collider operation for optimal performance becomes more and more cumbersome as the beam intensities and luminosity increase. The long-range effects which (besides being nonlinear) vary from bunch to bunch are particularly hard to mitigate. A comprehensive review of the beam-beam effects in the Tevatron Collider Run II can be found in Ref. [1]. The beam-beam effects have been the dominating sources of beam loss and lifetime limitations in the Tevatron proton-antiproton collider [1]. Electron lenses were originally proposed for compensation of electromagnetic long-range and head-on beam-beam interactions of proton and antiproton beams [2]. Results of successful employment of two electron lenses built and installed in the Tevatron are reported in [3,4,5]. In this paper we present design features of the Tevatron electron lenses (TELs), discuss the generation of electron beams, describe different modes of operation and outline the technical parameters of various subsystems.

  3. Experimental Studies of Compensation of Beam-Beam Effects with Tevatron Electron Lenses

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; /Fermilab; Alexahin, Yu.; Bishofberger, Kip; Kamerdzhiev, V.; Parkhomchuk, V.; Reva, V.; Solyak, N.; Wildman, D.; Zhang, X.-L.; Zimmermann, F.; /Fermilab /Los Alamos /Novosibirsk, IYF /CERN

    2008-02-01

    Applying the space-charge forces of a low-energy electron beam can lead to a significant improvement of the beam-particle lifetime limit arising from the beam-beam interaction in a high-energy collider [1]. In this article we present the results of various beam experiments with 'electron lenses', novel instruments developed for the beam-beam compensation at the Tevatron, which collides 980-GeV proton and antiproton beams. We study the dependencies of the particle betatron tunes on the electron beam current, energy and position; we explore the effects of electron-beam imperfections and noises; and we quantify the improvements of the high-energy beam intensity and the collider luminosity lifetime obtained by the action of the Tevatron Electron Lenses.

  4. Experimental studies of compensation of beam-beam effects with Tevatron electron lenses

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V; Alexahin, Y; Kamerdzhiev, V; Solyak, N; Wildman, D; Zhang, X-L [Fermi National Accelerator Laboratory, PO Box 500, Batavia, IL 60510 (United States); Bishofberger, K [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Parkhomchuk, V; Reva, V [Budker INP, Novosibirsk, 630090 (Russian Federation); Zimmermann, F [CERN, European Organization for Nuclear Research, CH-1211 Geneve (Switzerland)], E-mail: shiltsev@fnal.gov

    2008-04-15

    Applying the space-charge forces of a low-energy electron beam can lead to a significant improvement of the beam-particle lifetime limit arising from the beam-beam interaction in a high-energy collider. In this paper, we present the results of various beam experiments with 'electron lenses', novel instruments developed for the beam-beam compensation at the Tevatron, which collides 980 GeV proton and antiproton beams. We study the dependencies of the particle betatron tunes on the electron beam current, energy and position; we explore the effects of electron-beam imperfections and noises; and we quantify the improvements of the high-energy beam intensity and the collider luminosity lifetime obtained by the action of the Tevatron electron lenses.

  5. Generation and diagnostics of uncaptured beam in the Fermilab Tevatron and its control by electron lenses

    Directory of Open Access Journals (Sweden)

    Xiao-Long Zhang

    2008-05-01

    Full Text Available In the collider run II, the Tevatron operates with 36 high intensity bunches of 980 GeV protons and antiprotons. Particles not captured by the Tevatron rf system pose a threat since they can quench the superconducting magnets during acceleration or at beam abort. We describe the main mechanisms for the origination of this uncaptured beam, and present measurements of its main parameters by means of a newly developed diagnostics system. The Tevatron electron lens is effectively used in the collider run II operation to remove uncaptured beam and keep its intensity in the abort gaps at a safe level.

  6. Pulser for the Tevatron electron lens gun

    Energy Technology Data Exchange (ETDEWEB)

    Iouri Terechkine et al.

    2004-05-18

    To compensate for beam-beam interaction in Tevatron, an ''electron lens'' is considered to be an effective instrument. When a bunch of electrons with energy in the range (10-16) kV is overlapping with a bunch of antiprotons, the resulting focusing force for antiprotons can be adjusted by changing the electron beam current and by profiling its radial distribution. There exist several scenarios of how the system must function. According to one of them, an electron gun that supplies electrons must be fed by voltage pulses that follow with the frequency of antiproton bunches circulating in the Tevatron, which is about 2.5 MHz. To provide focusing tailored for each individual antiproton bunch, a modulator of the gun (pulser) must allow pulse-to-pulse voltage change. This report will cover main approaches to a design of a pulser for use with the gun of the Tevatron Electron Lens.

  7. Guide for 3D WARP simulations of hollow electron beam lenses. Practical explanation on basis of Tevatron electron lens test stand

    Energy Technology Data Exchange (ETDEWEB)

    Moens, Vince [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland)

    2014-06-08

    The purpose of this guide is to help successive students handle WARP. It outlines the installation of WARP on personal computers as well as super-computers and clusters. It furthermore teaches the reader how to handle the WARP environment and run basic scripts. Lastly it outlines how to execute the current Hollow Electron Beam Lens scripts.

  8. Electron lenses for super-colliders

    CERN Document Server

    Shiltsev, Vladimir D

    2016-01-01

    This book provides a comprehensive overview of the operating principles and technology of electron lenses in supercolliders.  Electron lenses are a novel instrument for high energy particle accelerators, particularly for the energy-frontier superconducting hadron colliders, including the Tevatron, RHIC, LHC and future very large hadron colliders.  After reviewing the issues surrounding beam dynamics in supercolliders, the book offers an introduction to the electron lens method and its application.  Further chapters describe the technology behind the electron lenses which have recently been proposed, built and employed for compensation of beam-beam effects and for collimation of high-energy high-intensity beams, for compensation of space-charge effects and several other applications in accelerators. The book will be an invaluable resource for those involved in the design, construction and operation of the next generation of hadron colliders.

  9. Electron lenses for the large hadron collider

    CERN Document Server

    Stancari†, G; Bruce, R; Redaelli, S; Rossi, A; Salvachua Ferrando, B

    2014-01-01

    Electron lenses are pulsed, magnetically confined electron beamswhose current-density profile is shaped to obtain the desired effect on the circulating beam. Electron lenses were used in the Fermilab Tevatron collider for bunch-bybunch compensation of long-range beam-beam tune shifts, for removal of uncaptured particles in the abort gap, for preliminary experiments on head-on beam-beamcompensation, and for the demonstration of halo scrapingwith hollow electron beams. Electron lenses for beam-beam compensation are being commissioned in RHIC at BNL. Within the US LHC Accelerator Research Program and the European HiLumi LHC Design Study, hollow electron beam collimation was studied as an option to complement the collimation system for the LHC upgrades. A conceptual design was recently completed, and the project is moving towards a technical design in 2014–2015 for construction in 2015–2017, if needed, after resuming LHC operations and re-assessing collimation needs and requirements at 6.5 TeV. Because of the...

  10. Magnetic electron lenses

    CERN Document Server

    1982-01-01

    No single volume has been entirely devoted to the properties of magnetic lenses, so far as I am aware, although of course all the numerous textbooks on electron optics devote space to them. The absence of such a volume, bringing together in­ formation about the theory and practical design of these lenses, is surprising, for their introduction some fifty years ago has created an entirely new family of commercial instruments, ranging from the now traditional transmission electron microscope, through the reflection and transmission scanning microscopes, to co­ lumns for micromachining and microlithography, not to mention the host of experi­ mental devices not available commercially. It therefore seemed useful to prepare an account of the various aspects of mag­ netic lens studies. These divide naturally into the five chapters of this book: the theoretical background, in which the optical behaviour is described and formu­ lae given for the various aberration coefficients; numerical methods for calculat­ ing...

  11. Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Stancari, Giulio [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Previtali, Valentina [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Valishev, Alexander [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Bruce, Roderik [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Redaelli, Stefano [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Rossi, Adriana [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Salvachua Ferrando, Belen [European Organization for Nuclear Research (CERN), Geneva (Switzerland)

    2014-06-26

    Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. We are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were checked to ensure that undesired effects were suppressed. Hardware specifications were based on the Tevatron devices and on preliminary engineering integration studies in the LHC machine. Required resources and a possible timeline were also outlined, together with a brief discussion of alternative halo-removal schemes and of other possible uses of electron lenses to improve the performance of the LHC.

  12. Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

    CERN Document Server

    Stancari, Giulio; Valishev, Alexander; Bruce, Roderik; Redaelli, Stefano; Rossi, Adriana; Salvachua Ferrando, Belen

    2014-01-01

    Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. Within the US LHC Accelerator Research Program (LARP) and the European FP7 HiLumi LHC Design Study, we are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were check...

  13. Simulation of Hollow Electron Beam Collimation in the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, I.A.; Stancari, G.; Valishev, A.; /Fermilab; Shatilov, D.N.; /Novosibirsk, IYF

    2012-05-01

    The concept of augmenting the conventional collimation system of high-energy storage rings with a hollow electron beam was successfully demonstrated in experiments at the Tevatron. A reliable numerical model is required for understanding particle dynamics in the presence of a hollow beam collimator. Several models were developed to describe imperfections of the electron beam profile and alignment. The features of the imperfections are estimated from electron beam profile measurements. Numerical simulations of halo removal rates are compared with experimental data taken at the Tevatron.

  14. Plans for Deployment of Hollow Electron Lenses at the LHC for Enhanced Beam Collimation

    Energy Technology Data Exchange (ETDEWEB)

    Redaelli, S. [CERN; Bertarelli, A. [CERN; Bruce, R. [CERN; Perini, D. [CERN; Rossi, A. [CERN; Salvachua, B. [CERN; Stancari, G. [Fermilab; Valishev, A. [Fermilab

    2015-06-01

    Hollow electron lenses are considered as a possible means to improve the LHC beam collimation system, providing active control of halo diffusion rates and suppressing the population of transverse halos. After a very successful experience at the Tevatron, a conceptual design of a hollow e-lens optimized for the LHC was produced. Recent further studies have led to a mature preliminary technical design. In this paper, possible scenarios for the deployment of this technology at the LHC are elaborated in the context of the scheduled LHC long shutdowns until the full implementation of the HL-LHC upgrade in 2023. Possible setups of electron beam test stands at CERN and synergies with other relevant electron beam programmes are also discussed.

  15. Biofuel cell as a power source for electronic contact lenses.

    Science.gov (United States)

    Falk, Magnus; Andoralov, Viktor; Blum, Zoltan; Sotres, Javier; Suyatin, Dmitry B; Ruzgas, Tautgirdas; Arnebrant, Thomas; Shleev, Sergey

    2012-01-01

    Here we present unequivocal experimental proof that microscale cofactor- and membrane-less, direct electron transfer based enzymatic fuel cells do produce significant amounts of electrical energy in human lachrymal liquid (tears). 100 μm diameter gold wires, covered with 17 nm gold nanoparticles, were used to fashion three-dimensional nanostructured microelectrodes, which were biomodified with Corynascus thermophilus cellobiose dehydrogenase and Myrothecium verrucaria bilirubin oxidase as anodic and cathodic bioelements, respectively. The following characteristics of miniature glucose/oxygen biodevices operating in human tears were registered: 0.57 V open-circuit voltage, about 1 μW cm(-2) maximum power density at a cell voltage of 0.5 V, and more than 20 h operational half-life. Theoretical calculations regarding the maximum recoverable electrical energy can be extracted from the biofuel and the biooxidant, glucose and molecular oxygen, each readily available in human lachrymal liquid, fully support our belief that biofuel cells can be used as electrical power sources for so called smart contact lenses. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Electron lenses for head-on beam-beam compensation in RHIC

    Science.gov (United States)

    Gu, X.; Fischer, W.; Altinbas, Z.; Anerella, M.; Bajon, E.; Bannon, M.; Bruno, D.; Costanzo, M.; Drees, A.; Gassner, D. M.; Gupta, R. C.; Hock, J.; Harvey, M.; Jain, A. K.; Jamilkowski, J. P.; Kankiya, P.; Lambiase, R.; Liu, C.; Luo, Y.; Mapes, M.; Marusic, A.; Mi, C.; Michnoff, R.; Miller, T. A.; Minty, M.; Nemesure, S.; Ng, W.; Phillips, D.; Pikin, A. I.; Rosas, P. J.; Robert-Demolaize, G.; Samms, T.; Sandberg, J.; Schoefer, V.; Shrey, T. C.; Tan, Y.; Than, R.; Theisen, C.; Thieberger, P.; Tuozzolo, J.; Wanderer, P.; Zhang, W.; White, S. M.

    2017-02-01

    Two electron lenses (e -lenses) have been in operation during the 2015 RHIC physics run as part of a head-on beam-beam compensation scheme. While the RHIC lattice was chosen to reduce the beam-beam-induced resonance-driving terms, the electron lenses reduced the beam-beam-induced tune spread. This has been demonstrated for the first time. The beam-beam compensation scheme allows for higher beam-beam parameters and therefore higher intensities and luminosity. In this paper, we detail the design considerations and verification of the electron beam parameters of the RHIC e -lenses. Longitudinal and transverse alignments with ion beams and the transverse beam transfer function measurement with head-on electron-proton beam are presented.

  17. Atomic force microscopy and scanning electron microscopy analysis of daily disposable limbal ring contact lenses

    OpenAIRE

    Lorenz, Kathrine Osborn; Kakkassery, Joseph; Boree, Danielle; Pinto, David

    2014-01-01

    Background Limbal ring (also known as ‘circle’) contact lenses are becoming increasingly popular, especially in Asian markets because of their eye-enhancing effects. The pigment particles that give the eye-enhancing effects of these lenses can be found on the front or back surface of the contact lens or ‘enclosed’ within the lens matrix. The purpose of this research was to evaluate the pigment location and surface roughness of seven types of ‘circle’ contact lenses. Methods Scanning electron ...

  18. Search for electroweak top quark production in the electron + jets channel in the D0 experiment at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Busato, Emmanuel [Paris Univ. (France)

    2005-04-01

    The top quark, whose mass approaches the electroweak symmetry breaking scale, is by far the heaviest known elementary particle. New physics is therefore expected to have its most important effect in the top sector. The Tevatron is, currently, the only collider able to produce the top quark. Among all possible production processes in the standard model, the top-antitop pair production via strong interaction, first observed in 1995, is the one with the largest cross section. The production via electroweak interaction (known as single top production), more difficult to extract from the background because of a lower cross section and of a lower signal to background ratio, has never been observed. In this thesis, we have searched for these processes by studying proton-antiproton collisions at $\\sqrt{s}$ =1.96 TeV produced by the Tevatron and detected with the DØ detector. The experimental study of the top quark is very sensitive to the quality of the data taken by the calorimeter. This detector showed, at the beginning of the Run II, rather important noise problems. Having identified the origin of the noise, new treatments at the offline level were implemented and their effects studied. It has been shown that these treatments reduce very significantly the effect of the noise in the reconstruction of physical quantities without notable degradation of the signal. Within the standard model, the top quark decays into W b with a branching ratio close to 100%. Leptonic decays of the into electron + neutrino have been used to identify the from the top decay. The main backgrounds to the single top signal ( +jets and QCD) are made essentially of light quark jets in the final state. Two ..-tagging algorithms have therefore been applied in order to improve the signal to background ratio. No evidence for electroweak top quark production has been found. Upper limits at the 95 % confidence level on the observed (expected) cross sections have be computed. They are found to be 14

  19. Effect of the electron lenses on the RHIC proton beam closed orbit

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X.; Luo, Y.; Pikin, A.; Okamura, M.; Fischer, W.; Montag, C.; Gupta, R.; Hock, J.; Jain, A.; Raparia, D.

    2011-02-01

    We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed at RHIC IR10. The transverse fields of the E-lenses bending solenoids and the fringe field of the main solenoids will shift the proton beam. We calculate the transverse kicks that the proton beam receives in the electron lens via Opera. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.

  20. Landau Damping of Beam Instabilities by Electron Lenses

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V. [Fermilab; Alexahin, Yuri; Burov, A. [Fermilab; Valishev, A. [Fermilab

    2017-06-26

    Modern and future particle accelerators employ increasingly higher intensity and brighter beams of charged particles and become operationally limited by coherent beam instabilities. Usual methods to control the instabilities, such as octupole magnets, beam feedback dampers and use of chromatic effects, become less effective and insufficient. We show that, in contrast, Lorentz forces of a low-energy, a magnetically stabilized electron beam, or "electron lens", easily introduces transverse nonlinear focusing sufficient for Landau damping of transverse beam instabilities in accelerators. It is also important that, unlike other nonlinear elements, the electron lens provides the frequency spread mainly at the beam core, thus allowing much higher frequency spread without lifetime degradation. For the parameters of the Future Circular Collider, a single conventional electron lens a few meters long would provide stabilization superior to tens of thousands of superconducting octupole magnets.

  1. Atomic force microscopy and scanning electron microscopy analysis of daily disposable limbal ring contact lenses.

    Science.gov (United States)

    Lorenz, Kathrine Osborn; Kakkassery, Joseph; Boree, Danielle; Pinto, David

    2014-09-01

    Limbal ring (also known as 'circle') contact lenses are becoming increasingly popular, especially in Asian markets because of their eye-enhancing effects. The pigment particles that give the eye-enhancing effects of these lenses can be found on the front or back surface of the contact lens or 'enclosed' within the lens matrix. The purpose of this research was to evaluate the pigment location and surface roughness of seven types of 'circle' contact lenses. Scanning electron microscopic (SEM) analysis was performed using a variable pressure Hitachi S3400N instrument to discern the placement of lens pigments. Atomic force microscopy (Dimension Icon AFM from Bruker Nano) was used to determine the surface roughness of the pigmented regions of the contact lenses. Atomic force microscopic analysis was performed in fluid phase under contact mode using a Sharp Nitride Lever probe (SNL-10) with a spring constant of 0.06 N/m. Root mean square (RMS) roughness values were analysed using a generalised linear mixed model with a log-normal distribution. Least square means and their corresponding 95% confidence intervals were estimated for each brand, location and pigment combination. SEM cross-sectional images at 500× and 2,000× magnification showed pigment on the surface of six of the seven lens types tested. The mean depth of pigment for 1-DAY ACUVUE DEFINE (1DAD) lenses was 8.1 μm below the surface of the lens, while the remaining lens types tested had pigment particles on the front or back surface. Results of the atomic force microscopic analysis indicated that 1DAD lenses had significantly lower root mean square roughness values in the pigmented area of the lens than the other lens types tested. SEM and AFM analysis revealed pigment on the surface of the lens for all types tested with the exception of 1DAD. Further research is required to determine if the difference in pigment location influences on-eye performance. © 2014 The Authors. Clinical and Experimental

  2. Celebrating the Tevatron legacy

    CERN Multimedia

    2012-01-01

    Fermilab hosted an exceptional event on 11 June: the Tevatron Impact symposium. More than 800 people attended to hear how the Tevatron advanced our understanding of fundamental physics.   A version of this "Director's Corner" by Pier Oddone first appeared in Fermilab Today on 12 June.   The development of accelerator technology for the Tevatron has influenced every subsequent major hadron accelerator. We heard reviews on the detector technologies and trigger systems developed with the Tevatron that are essential today for high-luminosity machines like the LHC. There were also talks on the superconducting-wire industry that made MRI magnets ubiquitous, and we discussed the major computational systems that use large farms of Linux-based commodity processors. Researchers who worked on the Tevatron also established multivariate analysis techniques that now allow us to squeeze the maximum information from complex data sets. One focus of the symposium was the ...

  3. Coupling in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gelfand, N.M.

    1994-12-01

    The performance of the Fermilab Tevatron Collider at the commencement of run Ib was far below expectations. After a frustrating period of several months, a low-{beta} quad downstream of the interaction point at B0 was found to be rolled. This rolled quadrupole coupled the horizontal and vertical motion of the Tevatron beams. It also made matching the beam from the Main Ring to the Tevatron impossible, resulting in emittance blow up on injection. The net result of the roll was a significant reduction in the Tevatron luminosity. When the roll in the quadrupole was corrected the performance of the Tevatron improved dramatically. This note will discuss the experimental data indicating the presence of coupling and subsequent calculations which show how coupling an affect the luminosity. It is not intended to exhaust a discussion of coupling, which hopefully will be understood well enough to be discussed in a subsequent note.

  4. Scanning Electron Microscopy Findings With Energy-Dispersive X-ray Investigations of Cosmetically Tinted Contact Lenses

    Science.gov (United States)

    Hotta, Fumika; Imai, Shoji; Miyamoto, Tatsuro; Mitamura-Aizawa, Sayaka; Mitamura, Yoshinori

    2015-01-01

    Objective: To investigate the surfaces and principal elements of the colorants of cosmetically tinted contact lenses (Cos-CLs). Methods: We analyzed the surfaces and principal elements of the colorants of five commercially available Cos-CLs using scanning electron microscopy with energy-dispersive x-ray analysis. Results: In two Cos-CLs, the anterior and posterior surfaces were smooth, and colorants were found inside the lens. One lens showed colorants located to a depth of 8 to 14 μm from the anterior side of the lens. In the other lens, colorants were found in the most superficial layer on the posterior surface, although a coated layer was observed. The colorants in the other three lenses were deposited on either lens surface. Although a print pattern was uniform in embedded type lenses, uneven patterns were apparent in dot-matrix design lenses. Colorants used in all lenses contained chlorine, iron, and titanium. In the magnified scanning electron microscopy images of a certain lens, chlorine is exuded and spread. Conclusions: Cosmetically tinted contact lenses have a wide variety of lens surfaces and colorants. Colorants may be deposited on the lens surface and consist of an element that has tissue toxicity. PMID:25799458

  5. Development of hollow electron beams for proton and ion collimation

    CERN Document Server

    Stancari, G.; Kuznetsov, G.; Shiltsev, V.; Still, D.A.; Valishev, A.; Vorobiev, L.G.; Assmann, R.; Kabantsev, A.

    2010-01-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams

  6. Development of hollow electron beams for proton and ion collimation

    CERN Document Server

    Stancari, G; Kuznetsov, G; Shiltsev, V; Still, D A; Valishev, A; Vorobiev, L G; Assmann, R; Kabantsev, A

    2012-01-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

  7. Imaging laser-wakefield-accelerated electrons using miniature magnetic quadrupole lenses

    Directory of Open Access Journals (Sweden)

    R. Weingartner

    2011-05-01

    Full Text Available The improvement of the energy spread, beam divergence, and pointing fluctuations are some of the main challenges currently facing the field of laser-wakefield acceleration of electrons. We address these issues by manipulating the electron beams after their generation using miniature magnetic quadrupole lenses with field gradients of ∼500  T/m. By imaging electron beams the spectral resolution of dipole magnet spectrometers can be significantly increased, resulting in measured energy spreads down to 1.0% rms at 190 MeV. The focusing of different electron energies demonstrates the tunability of the lens system and could be used to filter out off-target energies in order to reduce the energy spread even further. By collimating the beam, the shot-to-shot spatial stability of the beam is improved by a factor of 5 measured at a distance of 1 m from the source. Additionally, by deliberately transversely offsetting a quadrupole lens, the electron beam can be steered in any direction by several mrad. These methods can be implemented while still maintaining the ultrashort bunch duration and low emittance of the beam and, except for undesired electron energies in the energy filter, without any loss of charge. This reliable and compact control of laser-wakefield accelerated electron beams is independent of the accelerator itself, allowing immediate application of currently available beams.

  8. Physics at the Tevatron

    CERN Multimedia

    CERN. Geneva

    2006-01-01

    Physics Results from the Tevatron : The Tevatron proton-antiproton collider at Fermilab in the US is currently the world's highest energy collider. At the experiments CDF and D0 a broad physics programme is being pursued, ranging from flavour physics via electroweak precision measurements to searches for the Higgs boson and new particles beyond the Standard Model. In my lecture I will describe some of the highlight measurements in the flavour, electroweak and searches sectors, and the experimental techniques that are used.

  9. Tevatron AC dipole system

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, R.; Kopp, S.E.; /Texas U.; Jansson, A.; Syphers, M.J.; /Fermilab

    2007-06-01

    The AC dipole is an oscillating dipole magnet which can induce large amplitude oscillations without the emittance growth and decoherence. These properties make it a good tool to measure optics of a hadron synchrotron. The vertical AC dipole for the Tevatron is powered by an inexpensive high power audio amplifier since its operating frequency is approximately 20 kHz. The magnet is incorporated into a parallel resonant system to maximize the current. The use of a vertical pinger magnet which has been installed in the Tevatron made the cost relatively inexpensive. Recently, the initial system was upgraded with a more powerful amplifier and oscillation amplitudes up to 2-3{sigma} were achieved with the 980 GeV proton beam. This paper discusses details of the Tevatron AC dipole system and also shows its test results.

  10. Electron Lenses for Experiments on Nonlinear Dynamics with Wide Stable Tune Spreads in the Fermilab Integrable Optics Test Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Stancari, G. [Fermilab; Carlson, K. [Fermilab; McGee, M. W. [Fermilab; Nobrega, L. E. [Fermilab; Romanov, A. L. [Fermilab; Ruan, J. [Fermilab; Valishev, A. [Fermilab; Noll, D. [Frankfurt U.

    2015-06-01

    Recent developments in the study of integrable Hamiltonian systems have led to nonlinear accelerator lattice designs with two transverse invariants. These lattices may drastically improve the performance of high-power machines, providing wide tune spreads and Landau damping to protect the beam from instabilities, while preserving dynamic aperture. To test the feasibility of these concepts, the Integrable Optics Test Accelerator (IOTA) is being designed and built at Fermilab. One way to obtain a nonlinear integrable lattice is by using the fields generated by a magnetically confined electron beam (electron lens) overlapping with the circulating beam. The parameters of the required device are similar to the ones of existing electron lenses. We present theory, numerical simulations, and first design studies of electron lenses for nonlinear integrable optics.

  11. Analysis of nuclear fiber cell compaction in transparent and cataractous diabetic human lenses by scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Kuszak Jer R

    2003-01-01

    Full Text Available Abstract Background Compaction of human ocular lens fiber cells as a function of both aging and cataractogenesis has been demonstrated previously using scanning electron microscopy. The purpose of this investigation is to quantify morphological differences in the inner nuclear regions of cataractous and non-cataractous human lenses from individuals with diabetes. The hypothesis is that, even in the presence of the osmotic stress caused by diabetes, compaction rather than swelling occurs in the nucleus of diabetic lenses. Methods Transparent and nuclear cataractous lenses from diabetic patients were examined by scanning electron microscopy (SEM. Measurements of the fetal nuclear (FN elliptical angles (anterior and posterior, embryonic nuclear (EN anterior-posterior (A-P axial thickness, and the number of EN fiber cell membrane folds over 20 μm were compared. Results Diabetic lenses with nuclear cataract exhibited smaller FN elliptical angles, smaller EN axial thicknesses, and larger numbers of EN compaction folds than their non-cataractous diabetic counterparts. Conclusion As in non-diabetic lenses, the inner nuclei of cataractous lenses from diabetics were significantly more compacted than those of non-cataractous diabetics. Little difference between diabetic and non-diabetic compaction levels was found, suggesting that diabetes does not affect the degree of compaction. However, consistent with previous proposals, diabetes does appear to accelerate the formation of cataracts that are similar to age-related nuclear cataracts in non-diabetics. We conclude that as scattering increases in the diabetic lens with cataract formation, fiber cell compaction is significant.

  12. Tevatron physics results

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    I will summarize the physics results from the Tevatron experiments with particular emphasis on the experimental methods used in different kinds of analysis. In particular, the Tevatron is a proton-antiproton collider that has now accumulated more than 2 fb^-1 of luminosity in the two experiments, called CDF and D0. In this lecture I will review the results on inclusive productions of jets, W- and Z-bosons, the results in the flavor sector, the measurements of top production, searches for Higgs boson production and searches for physics beyond the Standard Model. In each case I will explain the basic experimental concepts and methods needed for making the measurement.

  13. Tevatron's complex collider cousins

    CERN Multimedia

    Fischer, W

    2004-01-01

    Letter referring to Schwarzschild's story "Disappointing performance and tight budgets confront Fermilab with tough decisions" and contesting that the Tevatron is not the most complex accelerator operating. They use the examples of CERN's SPS collider, HERA at DESY and the RHIC at Brookhaven (1/4 page)

  14. Beam Dynamics in an Electron Lens with the Warp Particle-in-cell Code

    CERN Document Server

    Stancari, Giulio; Redaelli, Stefano

    2014-01-01

    Electron lenses are a mature technique for beam manipulation in colliders and storage rings. In an electron lens, a pulsed, magnetically confined electron beam with a given current-density profile interacts with the circulating beam to obtain the desired effect. Electron lenses were used in the Fermilab Tevatron collider for beam-beam compensation, for abort-gap clearing, and for halo scraping. They will be used in RHIC at BNL for head-on beam-beam compensation, and their application to the Large Hadron Collider for halo control is under development. At Fermilab, electron lenses will be implemented as lattice elements for nonlinear integrable optics. The design of electron lenses requires tools to calculate the kicks and wakefields experienced by the circulating beam. We use the Warp particle-in-cell code to study generation, transport, and evolution of the electron beam. For the first time, a fully 3-dimensional code is used for this purpose.

  15. Supersymmetry at the Tevatron?

    Energy Technology Data Exchange (ETDEWEB)

    Lammel, S.

    1998-02-01

    These lectures contain an introduction to the search for supersymmetry at hadron colliders. The Tevatron is one of high-energy physics most sophisticated tools. The high center-of-mass energy of its proton-antiproton collisions makes it an ideal place to search for physics beyond the Standard Model, such as supersymmetry. Two experiments, CDF and D0, completed a long data taking period in summer of 1995, yielding over 100 pb{sup -1} of proton-antiproton interactions. The data recorded by the experiments are still being analyzed. The lectures outline the strategies in the search for supersymmetry at the Tevatron and examine the major analyses in detail. Results obtained by the two experiments are included where available.

  16. Measurement of the T quark mass in the electron-muon channel with the D0 detector at the Tevatron; Mesure de la masse du quark top dans le canal electron-muon aupres du detecteur D0 au TeVatron

    Energy Technology Data Exchange (ETDEWEB)

    Arthaud, M

    2008-06-15

    The standard model of particle physics is a theory that describes the elementary components of matter and their interactions. The top quark is the heaviest elementary particle described by this model and its mass is one of its free parameters. The measurement of this mass constrains the Higgs boson mass. At the moment of this study, it can be observed only with the 2 detectors located around the Tevatron which collides protons and antiprotons at a centre of mass energy of {radical}(s) = 1.96 TeV. In this thesis, the Run-II b data collected by the D0 detector between June 2006 and August 2007 (around 1 fb{sup -1}) have been analysed. The top quark is mainly produced by pairs and it decays in almost 100% of the time into a W boson and a bottom quark. In the final state studied here, one of the W bosons decays into an electron and a neutrino and the second one into a muon and a neutrino. Such a final state requires to control tightly the muon transverse momentum precision measurement. Events containing Z and J/{psi} decaying into 2 muons have been studied to adjust the momentum precision in simulated events to one observed in data. During the analysis, 77 top-anti-top events have been selected in the electron-muon channel to determine the top quark mass with a method based on the Monte-Carlo integration of the matrix element describing the production of a top-anti-top pair decaying into an electron and a muon. This yields a top quark mass value of m(top) equals (172 {+-} 4.2 (sta) {+-} 2.5 (syst)) GeV. (author)

  17. On the Asymmetric Focusing of Low-Emittance Electron Bunches via Active Lensing by Using Capillary Discharges

    Science.gov (United States)

    Bulanov, Stepan; Bagdasarov, Gennadiy; Bobrova, Nadezhda; Boldarev, Alexey; Olkhovskaya, Olga; Sasorov, Pavel; Gasilov, Vladimir; Barber, Samuel; Gonsalves, Anthony; Schroeder, Carl; van Tilborg, Jeroen; Esarey, Eric; Leemans, Wim; Levato, Tadzio; Margarone, Daniele; Korn, Georg; Kando, Masaki; Bulanov, Sergei

    2017-10-01

    A novel method for asymmetric focusing of electron beams is proposed. The scheme is based on the active lensing technique, which takes advantage of the strong inhomogeneous magnetic field generated inside the capillary discharge plasma to focus the ultrarelativistic electrons. The plasma and magnetic field parameters inside a capillary discharge are described theoretically and modeled with dissipative MHD simulations to enable analysis of capillaries of oblong rectangle cross-sections implying that large aspect ratio rectangular capillaries can be used to form flat electron bunches. The effect of the capillary cross-section on the electron beam focusing properties were studied using the analytical methods and simulation- derived magnetic field map showing the range of the capillary discharge parameters required for producing the high quality flat electron beams.

  18. Recent results from the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Vellidis, Costas; Bravina, L.; Foka, Y.; Kabana, S.

    2015-01-01

    The Tevatron p$\\bar{p}$ collider was shut down in 2011, after 10 years of high performance operation at a center-of-mass energy √s = 1.96 TeV in Run II. The two experiments, CDF and DZero, continue to analyze the collected data, aiming to extract all possible information regarding studies of the standard model and searches for new physics. A short review of some of the recent measurements at the Tevatron, and of the impact of the Tevatron program to high energy physics, is presented.

  19. Higgs Searches at the Tevatron

    CERN Document Server

    Evans, H G

    2000-01-01

    Higgs hunting is a world-wide sport and the Tevatron is set to become the next field of play when Run II starts in March 2001. To set the stage, we summarize results of searches for standard and non-standard Higgs bosons by CDF and Dzero in Run I at the Tevatron. Progress has been made in quantifying the requirements on the Tevatron Collider and on the upgraded experiments in Run II for extending the excellent work done at LEP. Armed with parameterizations of expected detector performance, the Tevatron Higgs Working group has made predictions of the sensitivity of CDF and Dzero to Higgs bosons in the Standard Model and in its Minimal Supersymmetric extension as a function of integrated luminosity. These predictions are presented to underscore the excitement being generated by Run II, and to highlight the need for the highest possible luminosity.

  20. Global searches at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Renkel, Peter; /Southern Methodist U.

    2009-01-01

    We present a review of global searches at the Tevatron with D0 and CDF detectors. The strategy involves splitting the data from the Tevatron into many final states and looking for signs of new physics in the high p{sub T} tails of various distributions using SLEUTH algorithm. CDF also utilizes Bump Hunter to search for narrow resonances in mass distributions. We analyzed 180 D0 final states, 9335 D0 distributions; 399 CDF final states and 19650 CDF distributions. No evidence of new physics is found.

  1. Achievements and Lessons from Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; /Fermilab

    2011-01-01

    For almost a quarter of a century, the Tevatron proton-antiproton collider was the centerpiece of the world's high energy physics program - beginning operation in December of 1985 until it was overtaken by LHC in 2011. The aim of the this unique scientific instrument was to explore the elementary particle physics reactions with center of mass collision energies of up to 1.96 TeV. The initial design luminosity of the Tevatron was 10{sup 30} cm{sup -2}s{sup -1}, however as a result of two decades of upgrades, the accelerator has been able to deliver 430 times higher luminosities to each of two high luminosity experiments, CDF and D0. Tevatron will be shut off September 30, 2011. The collider was arguably one of the most complex research instruments ever to reach the operation stage and is widely recognized for many technological breakthroughs and numerous physics discoveries. Below we briefly present the history of the Tevatron, major advances in accelerator physics, and technology implemented during the long quest for better and better performance. We also discuss some lessons learned from our experience.

  2. Hollow Electron Lens Simulation for the SPS

    CERN Document Server

    Previtali, V; Stancari, G; Valishev, A

    2013-01-01

    The hardware of the Tevatron hollow electron lens, which has been used in the past for collimation purposes, is presently available. Possible applications of similar devices in the LHC are under evaluation, but a realistic date for installation of electron lenses in the LHC would be not earlier than the machine shutdown scheduled for 2018. We investigated the possibility of beam tests with the available hardware in the meantime in the SPS. This article aims to answer this question by presenting the results of dedicated numerical simulations

  3. Electron Lenses and Cooling for the Fermilab Integrable Optics Test Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Stancari, G. [Fermilab; Burov, A. [Fermilab; Lebedev, V. [Fermilab; Nagaitsev, S. [Fermilab; Prebys, E. [Fermilab; Valishev, A. [Fermilab

    2015-11-05

    Recently, the study of integrable Hamiltonian systems has led to nonlinear accelerator lattices with one or two transverse invariants and wide stable tune spreads. These lattices may drastically improve the performance of high-intensity machines, providing Landau damping to protect the beam from instabilities, while preserving dynamic aperture. The Integrable Optics Test Accelerator (IOTA) is being built at Fermilab to study these concepts with 150-MeV pencil electron beams (single-particle dynamics) and 2.5-MeV protons (dynamics with self fields). One way to obtain a nonlinear integrable lattice is by using the fields generated by a magnetically confined electron beam (electron lens) overlapping with the circulating beam. The required parameters are similar to the ones of existing devices. In addition, the electron lens will be used in cooling mode to control the brightness of the proton beam and to measure transverse profiles through recombination. More generally, it is of great interest to investigate whether nonlinear integrable optics allows electron coolers to exceed limitations set by both coherent or incoherent instabilities excited by space charge.

  4. Head-on beam-beam compensation with electron lenses in the RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    Luo,Y.; FischW; Abreu, N.; Beebe, E.; Montag, C.; Okamura, M.; Pikin, A.; Robert-Demolaize, G.

    2008-06-23

    The working point for the polarized proton run in the Relativistic Heavy Ion Collider is constrained between 2/3 and 7/10 in order to maintain good beam lifetime and polarization. To further increase the bunch intensity to improve the luminosity, a low energy Gaussian electron beam, or an electron lens is proposed to head-on collide with the proton beam to compensate the large tune shift and tune spread generated by the proton-proton beam-beam interactions at IP6 and IP8. In this article, we outline the scheme of head-on beam-beam compensation in the RHIC and give the layout of e-lens installation and the parameters of the proton and electron beams. The involved physics and engineering issues are shortly discussed.

  5. Electroweak results from the tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Wood, D. [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    1997-01-01

    Electroweak results are presented from the CDF and DO experiments based on data collected in recent runs of the Fermilab Tevatron Collider. The measurements include the mass and width of the W boson, the production cross sections of the W and Z bosons, and the W charge asymmetry. Additional results come from studies of events with pairs of electroweak gauge bosons and include limits on anomalous couplings.

  6. Hot topics from the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Glenzinski, D.; /Fermilab

    2008-01-01

    The Tevatron Run-II began in March 2001. To date, both the CDF and D0 experiments have collected 1 fb{sup -1} of data each. The results obtained from this data set were summarized at this conference in 39 parallel session presentations covering a wide range of topics. The author summarizes the most important of those results here and comments on some of the prospects for the future.

  7. B States at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Paulini, Manfred; /Carnegie Mellon U.

    2009-06-01

    The CDF and D0 experiments have produced a wealth of heavy flavor physics results since the beginning of RunII of the Fermilab Tevatron. They review recent measurements of B hadron states including excited B states (B**, B{sub s}**) and the B{sub c}{sup +} meson. They also summarize the discoveries of the {Sigma}{sub b} baryon states and the {Xi}{sub b}{sup -} baryon.

  8. Magnifying Lenses with Weak Achromatic Bends for High-Energy Electron Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Walstrom, Peter Lowell [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-27

    This memo briefly describes bremsstrahlung background effects in GeV-range electron radiography systems and the use of weak bending magnets to deflect the image to the side of the forward bremsstrahlung spot to reduce background. The image deflection introduces first-order chromatic image blur due to dispersion. Two approaches to eliminating the dispersion effect to first order by use of magnifying lens with achromatic bends are described. Also, higher-order image blur terms caused by weak bends are also discussed, and shown to be negligibly small in most cases of interest.

  9. SUSY searches at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jaffre, Michel; /Orsay, LAL

    2012-02-01

    The Tevatron collider has provided the CDF and D0 collaborations with large datasets as input to a rich program of physics beyond the standard model. The results presented here are from recent searches for SUSY particles using up to 6 fb{sup -1} of data. Supersymmetry (SUSY) [1] is one of the most favored theories beyond the standard model (SM). Each SM particle is associated to a sparticle whose spin differs by one half unit. This boson-fermion symmetry is obviously broken by some unknown mechanism. Even in the minimal supersymmetric extension of the SM (MSSM [2]) there are a large number of free parameters. To reduce this number one can introduce new assumptions on the symmetry breaking mechanism and build models based on minimal supergravity (as mSUGRA [3]) or on a Gauge Mediated Symmetry Breaking scenario (GMSB [4]), a top-down approach. Another possibility is to make phenomenological assumptions to reduce the number of particles accessible to the experiment while keeping some of the properties of the above models (bottom-up approach). As the sparticles are heavy, to produce them one has to make collisions at the highest center of mass energy. The Tevatron was the best place for discovery until the start of LHC. In the near term, Tevatron experiments and their large datasets remain competitive in areas like production of third generation squarks and of non-coloured sparticles. I will report on recent results from the CDF and D0 collaborations, assuming R-parity is conserved, i.e the sparticles are produced in pairs, and the lightest of them (LSP) is stable, neutral, weakly interacting, and detected as missing transverse energy, E{sub T}.

  10. Jet physics at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    S. Seidel

    2002-05-29

    Recent analyses by the CDF and D0 Collaborations of jet data produced in p{bar p} collisions at the Fermilab Tevatron Collider are presented. These include new studies of the inclusive jet production cross section, a measurement of the strong coupling constant, the first measurement of subjet multiplicity of quark and gluon jets, examination of ratios of multijet cross sections and their implications for choice of renormalization scale, and a study of charged jet evolution and energy flow in the underlying event. The results are compared to theoretical predictions.

  11. Jet Physics at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Bhatti, Anwar; Lincoln, Don

    2010-02-01

    Jets have been used to verify the theory of quantum chromodynamics (QCD), measure the structure of the proton and to search for the physics beyond the Standard Model. In this article, we review the current status of jet physics at the Tevatron, a {radical}s = 1.96 TeV p{bar p} collider at the Fermi National Accelerator Laboratory. We report on recent measurements of the inclusive jet production cross section and the results of searches for physics beyond the Standard Model using jets. Dijet production measurements are also reported.

  12. Supersymmetry results at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Manca, Giulia; /Liverpool U.

    2005-05-01

    The Run II physics programme of the Tevatron is proceeding with more than 300 pb{sup -1} of analysis quality data, collected at a center-of-mass energy of 1.96 TeV. Searches for supersymmetric particles are starting to set new limits, improving over the LEP and Run I results and exploring new regions of parameter space. They present recent results in Supersymmetry with the upgraded CDF and D0 detectors and give some prospects for the future of these searches.

  13. Gravitational lensing

    CERN Document Server

    Dodelson, Scott

    2017-01-01

    Gravitational lensing is a consequence of general relativity, where the gravitational force due to a massive object bends the paths of light originating from distant objects lying behind it. Using very little general relativity and no higher level mathematics, this text presents the basics of gravitational lensing, focusing on the equations needed to understand the phenomena. It then applies them to a diverse set of topics, including multiply imaged objects, time delays, extrasolar planets, microlensing, cluster masses, galaxy shape measurements, cosmic shear, and lensing of the cosmic microwave background. This approach allows undergraduate students and others to get quickly up to speed on the basics and the important issues. The text will be especially relevant as large surveys such as LSST and Euclid begin to dominate the astronomical landscape. Designed for a one semester course, it is accessible to anyone with two years of undergraduate physics background.

  14. Ophthalmic Lenses

    CERN Document Server

    Bhootra, Ajay Kumar

    2009-01-01

    This book is uniquely meant for the ophthalmologists, optometrists and opticians to help the world see better by excellent vision through the services of technicians and clinical principle based ophthalmology so that the management of ocular problems can be done for a better vision . Informs that a wide range of material and design of ophthalmic lenses with innovative developments is available. This book presents comprehensively rich information about the ophthalmic lenses and their dispensing tips . It will be highly useful mainly for the students of optometry and opticians, ophthalmologists,

  15. Soft Lenses*

    African Journals Online (AJOL)

    Polyhema. Low water content-30 - 40% therefore less well tolerated. Impermeable to gases. Low elasticity and therefore optics not good. Subject to stress and strain especially when drying. Easily infected. A series of cases fitted with Bionite soft lenses is described. Good results were obtained in bullous kera- topathy, dry.

  16. TEVATRON Phase 1, February, 1980

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1980-02-01

    This report describes the "Tevatron Phase 1 project at the Fermi National Accelerator Laboratory. The project follows research and development efforts and the earlier Energy Saver project. The Research and Development work has led to the development and fabrication of superconducting· accelerator magnets and installation of a test string of magnets in A sector of the Main-Ring tunnel. The Energy Saver project, authorized in FY79 and now in progress, includes construction of a complete ring of superconducting magnets and their installation in the Main-Ring tunnel. The project includes refrigeration and rf equipment adequate for sustained operation of the ring at a peak energy of 500 GeV, making use of the existing experimental areas....

  17. Beam instrumentation for the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Ronald S.; Jansson, Andreas; Shiltsev, Vladimir; /Fermilab

    2009-10-01

    The Tevatron in Collider Run II (2001-present) is operating with six times more bunches and many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for future colliders.

  18. Academic Training - Tevatron: studying pp collisions at the highest energy

    CERN Multimedia

    2006-01-01

    ACADEMIC TRAINING LECTURE SERIES 15, 16, 17, 18 May Main Auditorium, bldg. 500 on 15, 16, 17 May - Council Chamber on 18 May Physics at the Tevatron B. HEINEMANN, Univ. of Liverpool, FERMILAB Physics Results from the Tevatron The Tevatron proton-antiproton collider at Fermilab in the US is currently the world's highest energy collider. At the experiments CDF and D0 a broad physics programme is being pursued, ranging from flavour physics via electroweak precision measurements to searches for the Higgs boson and new particles beyond the Standard Model. In my lecture I will describe some of the highlight measurements in the flavour, electroweak and searches sectors, and the experimental techniques that are used. ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch If you wish to participate in one of the following courses, please tell to your supervisor and apply electronically from the course description pages that can be found on the Web at: http://www.cern.ch/...

  19. Beyond the Standard Model - Searches at HERA and the Tevatron

    CERN Document Server

    Gruenendahl, Stefan

    2008-01-01

    Searches for Physics beyond the Standard Model have entered an exciting new phase: the complete HERA data samples obtained until the end of operations in the Summer of 2007 are now available for analysis. ZEUS and H1 have each collected about 0.5 fb^{-1} of lepton proton data, distributed over electron and positron running, and over different lepton beam polarisations. At the same time the Fermilab Tevatron proton-antiproton collider is accumulating data at unprecedented rates, with current analyses based on up to 3 fb^{-1}. The Tevatron experiments DZERO and CDF have each already recorded over 4 fb^{-1} (Fall 2008), and are aiming for a total of 8 fb^{-1} of antiproton-proton collisions at 2 TeV center-of-mass energy for Tevatron Run II. I am presenting recent updates (from the last 12 months) on searches, grouped loosely into three classes: well-established `traditional' searches, mostly for very specific signatures and models, more recent and/or more generalized searches for broader classes of phenomena, a...

  20. Tevatron Alignment Issues 2003-2004

    CERN Document Server

    Volk, James T; Elementi, Luciano; Gelfand, Norman M; Gollwitzer, Keith; Greenwood, John A; Martens, Michael A; Moore, Craig D; Nobrega, Alfred; Russell, Allison D; Sager, Terry; Shiltsev, Vladimir; Stefanski, Raymond; Syphers, Michael J; Wojcik, George

    2005-01-01

    It was observed during the early part of Run II that dipole corrector currents in the Tevatron were changing over time. Measurement of the roll for dipoles and quadrupoles confirmed that there was a slow and systematic movement of the magnets from their ideal position. A simple system using a digital protractor and laptop computer was developed to allow roll measurements of all dipoles and quadrupoles. These measurements showed that many magnets in the Tevatron had rolled more than 1 milli-radian. To aid in magnet alignment a new survey network was built in the Tevatron tunnel. This network is based on the use of free centering laser tracker. During the measurement of the network coordinates for all dipole, quadrupole and corrector magnets were obtained. This paper discusses roll measurement techniques and data, the old and new Tevatron alignment network.

  1. Searches for supersymmetry at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Mary R. M. Bishai

    2001-05-15

    We review current experimental results of searches for Supersymmetry (SUSY) at the Fermilab Tevatron Collider using the Run I data collected during 1992-1996. New results from the CDF detector in the jets + missing E{sub t} and lepton-photon channels are presented. Recent results from model independent searches at D0 using the SLEUTH algorithm are reviewed. We discuss the prospects for supersymmetry searches at Run II of the Tevatron, scheduled to start in March, 2001.

  2. Top physics at the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Margaroli, Fabrizio; /Purdue U.

    2007-10-01

    The top quark has been discovered in 1995 at the CDF and DO experiments located in the Tevatron ring at the Fermilab laboratory. After more than a decade the Tevatron collider, with its center-of-mass energy collisions of 1.96 TeV, is still the only machine capable of producing such exceptionally heavy particle. Here I present a selection of the most recent CDF and DO measurements performed analyzing {approx} 1 fb{sup -1} of integrated luminosity.

  3. QCD measurements at the Tevatron

    CERN Document Server

    ,

    2011-01-01

    Selected quantum chromodynamics (QCD) measurements performed at the Fermilab Run II Tevatron ppbar collider running at sqrt{s} = 1.96 TeV by CDF and D0 Collaborations are presented. The inclusive jet, dijet production and three-jet cross section measurements are used to test perturbative QCD calculations, constrain parton distribution function (PDF) determinations, and extract a precise value of the strong coupling constant, alpha_s(m_Z) = 0.1161^{+0.0041}_{-0.0048}. Inclusive photon production cross-section measurements reveal an inability of next-to-leading-order (NLO) perturbative QCD (pQCD) calculations to describe low-energy photons arising directly in the hard scatter. The diphoton production cross-sections check the validity of the NLO pQCD predictions, soft-gluon resummation methods implemented in theoretical calculations, and contributions from the parton-to-photon fragmentation diagrams. Events with W/Z+jets productions are used to measure many kinematic distributions allowing extensive tests and tu...

  4. Applying EVM principles to Tevatron Beam Position Monitor Project

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Bakul; /Fermilab

    2005-08-01

    At Fermi National Accelerator Laboratory (Fermilab), the Tevatron high energy particle collider must meet the increasing scientific demand of higher beam luminosity. To achieve this higher luminosity goal, U. S. Department of Energy (DOE) sponsored a major upgrade of capabilities of Fermilab's accelerator complex that spans five years and costs over fifty million dollars. Tevatron Beam Position Monitor (BPM) system upgrade is a part of this project, generally called RunII upgrade project. Since the purpose of the Tevatron collider is to detect the smashing of proton and anti-protons orbiting the circular accelerator in opposite directions, capability to detect positions of both protons and antiprotons at a high resolution level is a desirable functionality of the monitoring system. The original system was installed during early 1980s, along with the original construction of the Tevatron. However, electronic technology available in 1980s did not allow for the detection of significantly smaller resolution of antiprotons. The objective of the upgrade project is to replace the existing BPM system with a new system utilizing capabilities of modern electronics enhanced by a front-end software driven by a real-time operating software. The new BPM system is designed to detect both protons and antiprotons with increased resolution of up to an order of magnitude. The new system is capable of maintaining a very high-level of data integrity and system reliability. The system consists of 27 VME crates installed at 27 service buildings around the Tevatron ring servicing 236 beam position monitors placed underground, inside the accelerator tunnel. Each crate consists of a single Timing Generator Fanout module, custom made by Fermilab staff, one MVME processor card running VxWorks 5.5, multiple Echotek Digital Receiver boards complimented by custom made Filter Board. The VxWorks based front-end software communicates with the Main Accelerator Control software via a special

  5. Electron identification and application to the measurement of the production cross section of the top quark with the Ddiameter detector at Tevatron; Identification d'electrons et application a la mesure de la section efficace de production du quark top avec le detecteur Ddiametre au TeVatron

    Energy Technology Data Exchange (ETDEWEB)

    Beaudette, F

    2003-04-01

    The tagging of heavy flavour quarks is crucial for several standard model studies such as the Higgs boson identification through its decay into b quark pairs, or top quark studies. The reconstruction of electrons and muons inside jets is one of the tools used for heavy flavour tagging. In D0 at Run-1, only soft muon tagging was possible since there was no magnetic field in the central detector. The detector has been upgraded for Run-2, and heavy flavour tagging with electrons became possible thanks to a new superconducting magnet. I developed the so-called road algorithm for this purpose. It benefits from the new capability of the tracker and from the good calorimeter properties. Its performance are studied in detail with generated events as well as with real data. The identification efficiency and the mis-identification rate are determined with physics signals. The capability of the road method for b tagging is demonstrated. Heavy flavour tagging with leptons in jets can be efficiently applied to the top quark 'rediscovery'. Indeed, the leptons from semi-leptonic decays of b quarks are very hard and central. The analysis is carried out in the electron-plus-jet and muon-plus-jet channels simultaneously. For the first measurement of the cross section of top quark production in Run-2, only the tagging with muons is used. The measured value for the cross section of tt-bar production at {radical}s 1.96 TeV is 8.5 (+4.5-3.6)(stat) (+6.3-3.5)(sys) ({+-}0.8)(lumi) pb. The tagging with electrons requires a specific optimization, but once it is performed the good efficiency of the road method is confirmed. Several ways to improve it are proposed. One of the most promising is the extension of the road method to the pre-shower detectors. (author)

  6. Search for higgs, leptoquarks, and exotics at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Song Ming Wang

    2004-06-22

    This paper reviews some of the most recent results from the CDF and D0 experiments on the searches for Standard Model and Non-Standard Model Higgs bosons, and other new phenomena at the Tevatron. Both experiments examine data from proton anti-proton collision at {radical}s = 1.96 TeV, of integrated luminosity {approx} 200 pb{sup -1} (per experiment), to search for Higgs predicted in the Standard Model and beyond Standard Model, supersymmetric particles in the Gauge Mediated Symmetry Breaking scenario, leptoquarks, and excited electrons. No signal was observed, and limits on the signatures and models are derived.

  7. From the Tevatron to Project X

    CERN Multimedia

    Pier Oddone, Fermilab director (from CERN Courier)

    2011-01-01

    In the October issue of the CERN Courier, Fermilab Director Pier Oddone will present the past, present and future of the US laboratory after the Tevatron. The Bulletin presents some early extracts from his article…   Fermilab Director, Pier Oddone. The end of September marks the end of an era at Fermilab, with the shutdown of the Tevatron after 28 years of operation at the frontiers of particle physics. The Tevatron’s far-reaching legacy spans particle physics, accelerator science and industry. The collider established Fermilab as a world leader in particle physics research, a role that will be strengthened with a new set of facilities, programmes and projects in neutrino and rare-process physics, astroparticle physics, and accelerator and detector technologies. The Tevatron exceeded every expectation ever set for it. This remarkable machine achieved luminosities with antiprotons once considered impossible, reaching more than 4x1032 cm-2s-1 instantaneous luminosity and...

  8. Contributions to the mini-workshop on beam-beam compensation in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.

    1998-02-01

    The purpose of the Workshop was to assay the current understanding of compensation of the beam-beam effects in the Tevatron with use of low-energy high-current electron beam, relevant accelerator technology, along with other novel techniques of the compensation and previous attempts. About 30 scientists representing seven institutions from four countries--FNAL, SLAC, BNL, Novosibirsk, CERN, and Dubna were in attendance. Twenty one talks were presented. The event gave firm ground for wider collaboration on experimental test of the compensation at the Tevatron collider. This report consists of vugraphs of talks given at the meeting.

  9. Exclusive e+e-, di-photon and di-jet production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Terashi, Koji; /Rockefeller U.

    2007-05-01

    Results from studies on exclusive production of electron-position pair, di-photon, and dijet production at CDF in proton-antiproton collisions at the Fermilab Tevatron are presented. THe first observation and cross section measurements of exclusive e{sup +}e{sup -} and di-jet production in hadron-hadron collisions are emphasized.

  10. Contact lenses following keratoplasty.

    Science.gov (United States)

    Beekhuis, W H; van Rij, G; Eggink, F A; Vreugdenhil, W; Schoevaart, C E

    1991-01-01

    Bandage contact lenses can be used following keratoplasty to protect the ocular surface and promote epithelial healing. Rigid gas permeable contact lenses are indicated to correct irregular astigmatism and anisometropia. The Rotterdam Eye Hospital fit 77 keratoplasty patients with contact lenses following their surgery. The methods of fitting contact lenses over the irregular or highly astigmatic surface of a graft are discussed.

  11. Top and Electroweak Measurements at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Bartos, P. [Comenius U.

    2016-01-01

    In this report, we summarize the latest results of the top-quark mass and electroweak measurements from the Tevatron. Since the world combination of top-quark mass measurements was done, CDF and D0 experiments improved the precision of several results. Some of them reach the relative precition below 1% for a single measurement. From the electroweak results, we report on the WW and WZ production cross section, measurements of the weak mixing angle and indirect measurements of W boson mass. The Tevatron results of the weak mixing angle are still the most precise ones of hadron colliders.

  12. Fitting the Luminosity Decay in the Tevatron

    CERN Document Server

    McCrory, Elliott; Slaughter, Anna Jean; Xiao, Aimin

    2005-01-01

    This paper explores the various ways in which the decay of the luminosity in the Tevatron have been fit. The standard assumptions of a fixed-lifetime exponential decay are only appropriate for very short time intervals. A "1/time" funcional form fits rather well, and is supported by analytical derivations. A more complex form, assuming a time-varying lifetime, produces excellent results. Changes in the luminosity can be factored into two phenomena: The luminosity burn-off rate, and the burn-off rate from non-luminosity effects. The luminous and the non-luminous burn rate are shown for stores in the Tevatron.

  13. The Tevatron bunch by bunch longitudinal dampers

    Energy Technology Data Exchange (ETDEWEB)

    Cheng-Yang Tan and James Steimel

    2002-09-25

    We describe in this paper the Tevatron bunch by bunch dampers. The goal of the dampers is to stop the spontaneous longitudinal beam size blowup of the protons during a store. We will go through the theory and also show the measured results during the commissioning of this system. The system is currently operational and have stopped the beam blowups during a store.

  14. WW and WZ production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Lipeles, Elliot; /UC, San Diego

    2007-01-01

    This report summarizes recent measurements of the production properties of WW and WZ pairs of bosons at the Tevatron. This includes measurements of the cross-section and triple gauge couplings in the WW process and the first evidence for WZ production.

  15. Photon final states at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Campanelli, Mario; /University Coll. London

    2008-04-01

    The authors present here several recent measurements involving associate production of photons and jets at the Tevatron. In particular, inclusive photon + met from D0, and photon + b-jets and photon + b-jet + leptons + MET from CDF are described in some detail. These measurements offer a good test of QCD predictions in rather complex final states.

  16. Tevatron sees light at end of tunnel?

    CERN Multimedia

    Seife, C

    2002-01-01

    Physicists at Fermilab are finally starting to get on top of problems with the beam luminosity of the Tevatron. After a million dollar refit last year, every single luminosity target has been missed since it went operational six months ago (1 page).

  17. Are PDFs still consistent with Tevatron data?

    Directory of Open Access Journals (Sweden)

    Sullivan Zack

    2018-01-01

    Full Text Available As active data taking has moved to the LHC at CERN, more and more LHC data have been included into fits of parton distribution functions. An anomaly has arisen where formerly excellent agreement between theoretical predictions and experiment in single-top-quark production at the Tevatron is no longer quite as good. Is this indicative of a deeper issue?

  18. Parton distributions: HERA-Tevatron-LHC

    CERN Document Server

    Watt, Graeme

    2009-01-01

    The parton distribution functions (PDFs) are a non-negotiable input to almost all theory predictions at hadron colliders. In this talk, I introduce PDF determination by global analysis and discuss selected topics concerning recent relevant data from HERA and the Tevatron, before giving some prospects for the LHC. The combination of H1 and ZEUS cross sections reduces uncertainties and will be an important input to future global PDF analyses. The theoretical description of the heavy-quark contribution to structure functions at HERA has a significant influence on predictions at the LHC. New W and Z data from the Tevatron Run II provide important PDF constraints, but there are currently problems describing the latest data on the lepton charge asymmetry from W -> l nu decays. The Tevatron Run II jet production data prefer a smaller high-x gluon than the previous Run I data, which impacts on predictions for Higgs cross sections at the Tevatron. It is now possible to consistently calculate a combined "PDF+alpha_S" u...

  19. The Physics Case for Extended Tevatron Running

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Darien R.

    2010-11-01

    Run II of the Tevatron collider at Fermilab is currently scheduled to end late in 2011. Given the current performance of the collider and of the CDF and D0 detectors, it is estimated that the current data set could be approximately doubled with a run extended into 2014. A few examples are presented of the physics potential of these additional statistics. These are discussed in the context of the expected reach of the LHC 7 TeV data and the existing Tevatron data. In particular, an extraordinary opportunity is described which could probe the existence of a standard model Higgs boson with mass in the currently preferred region between 115 GeV and 150 GeV.

  20. Electron optics

    CERN Document Server

    Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

    1972-01-01

    Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

  1. Heavy Flavor Baryons at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Kuhr, Thomas

    2011-09-01

    The Tevatron experiments CDF and D0 have filled many empty spots in the spectrum of heavy baryons over the last few years. The most recent results are described in this article: The first direct observation of the {Xi}{sub b}{sup 0}, improved measurements of {Sigma}{sub b} properties, a new measurement of the {Lambda}{sub b} {yields} J/{psi}{Lambda} branching ratio, and a high-statistics study of charm baryons.

  2. Recent QCD Studies at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Group, Robert Craig

    2008-04-01

    Since the beginning of Run II at the Fermilab Tevatron the QCD physics groups of the CDF and D0 experiments have worked to reach unprecedented levels of precision for many QCD observables. Thanks to the large dataset--over 3 fb{sup -1} of integrated luminosity recorded by each experiment--important new measurements have recently been made public and will be summarized in this paper.

  3. Higgs results from the Tevatron Run II

    Energy Technology Data Exchange (ETDEWEB)

    Tuchming, B.; /DAPNIA, Saclay

    2005-01-01

    The data taken at the Tevatron experiments have been analyzed to search for Higgs bosons. For the Standard Model Higgs searches, no excess is observed, the data are in good agreement with the expectations, so that limits are set on the production rates. For various theoretical models beyond the Standard Model, there is no excess either, which allows to derive constraints in their respective parameter spaces.

  4. Longitudinal damping in the Tevatron collider

    Energy Technology Data Exchange (ETDEWEB)

    Kerns, Q.A.; Jackson, G.; Kerns, C.R.; Miller, H.; Reid, J.; Siemann, R.; Wildman, D.

    1989-03-01

    This paper describes the damper design for 6 proton on 6 pbar bunches in the Tevatron collider. Signal pickup, transient phase detection, derivative networks, and phase correction via the high-level rf are covered. Each rf station is controlled by a slow feedback loop. In addition, global feedback loops control each set of four cavities, one set for protons and one set for antiprotons. Operational experience with these systems is discussed. 7 refs., 9 figs.

  5. $B$ mixing and lifetimes at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ceballos, G.; Piedra, J.

    2006-04-01

    The Tevatron collider at Fermilab provides a very rich environment for the study of b-hadrons. Both the D0 and CDF experiments have collected a sample of about 1 fb{sup -1}. they report results on three topics: b-hadron lifetimes, polarization amplitudes and the decay width difference in B{sub s}{sup 0} {yields} J/{psi}{phi}, and B{sub s}{sup 0} mixing.

  6. Di-boson production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    De Lentdecker, Gilles; /Rochester U.

    2005-05-01

    The authors present some precision measurements on electroweak physics performed at the Tevatron collider at Fermilab. Namely they report on the boson-pair production cross sections and on triple gauge boson couplings using proton anti-proton collisions collected by the CDF and D0 experiments at the center-of-mass energy of 1.96 TeV. The data correspond to an integrated luminosity of up to 324 pb{sup -1}.

  7. Surface analysis of hydrogel contact lenses by ESCA.

    Science.gov (United States)

    Hart, D E; DePaolis, M; Ratner, B D; Mateo, N B

    1993-07-01

    We used electron spectroscopy for chemical analysis (ESCA) to examine the surface chemistry of polymacon, tefilcon, and bufilcon hydrogel contact lenses. Worn and unworn water-cleaned and surfactant-cleaned lenses were compared. The surface chemistry of unworn lenses, which were used as controls, consisted of approximately 70% carbon, 25% oxygen, and silicon, sulfur, sodium, nitrogen, and zinc). In general, surfactant cleaning removed silicon contamination, but left a residue containing sulfur and zinc. The increase in the nitrogen/carbon (N/C) ratio for worn bufilcon and polymacon lenses was significantly greater than the N/C ratio for unworn bufilcon and polymacon lenses. As a group the worn ionic lenses (bufilcon) showed a greater N/C ratio than the worn nonionic lenses (polymacon, tefilcon). The nitrogen that appears on all worn lenses probably represents adherent as well as adsorbed surface proteins. The highest N/C ratios were found on a pair of pathologically deposited lenses and on the lens with the longest wearing time (2 years). For the bufilcon and polymacon lenses, the differences observed in the ESCA data for the unworn and worn lenses suggest that contact lenses begin interacting with the tear film within 1 minute (the shortest wearing time in this study).

  8. Fixed target issues for the Tevatron Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Stefanski, R.

    1988-08-29

    The Tevatron Upgrade poses some interesting prospects for the Fixed-Target program if an option to extract the high energy proton beam is preserved. This paper presents a summary of the advantages of increased energy for fixed target experiments, and evaluates some of the more challenging technical issues. In particular, Bottom production, muon and neutrino interactions, and polarized /bar p/ experiments would benefit substantially from a higher energy primary beam. The new Main Injector will also be important for fixed target experiments as a source for test beams and intense kaon and neutrino beams. 4 refs., 2 tabs.

  9. Baryon spectroscopy results at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Van Kooten, R.; /Indiana U.

    2010-01-01

    The Tevatron at Fermilab continues to collect data at high luminosity resulting in datasets in excess of 6 fb{sup -1} of integrated luminosity. The high collision energies allow for the observation of new heavy quark baryon states not currently accessible at any other facility. In addition to the ground state {Lambda}{sub b}, the spectroscopy and properties of the new heavy baryon states {Omega}{sub b}, {Xi}{sub b}, and {Sigma}{sub b}{sup (*)} as measured by the CDF and D0 Collaborations are presented.

  10. Recent QCD results from the Tevatron

    CERN Document Server

    Wobisch, M

    2012-01-01

    Recent QCD related results from the CDF and the D0 experiments are presented based on proton anti-proton collision data at sqrt(s)=1.96 TeV, taken in Run II of the Fermilab Tevatron Collider. Measured observables include inclusive photon and diphoton production, vector boson plus jets production, event shape variables, and inclusive multijet production. The measurement results are compared to QCD theory calculations in different approximations. A determination of the strong coupling constant from jet data is presented.

  11. Review of Physics Results from the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Bandurin, D. [Virginia U.; Bernardi, G. [Paris U., VI-VII; Gerber, C. [Chicago U., EFI; Junk, T. [Fermilab; Juste, A. [Barcelona, IFAE; Kotwal, A. [Duke U.; Lewis, J. [Fermilab; Mesropian, C. [Rockefeller U.; Schellman, H. [Northwestern U.; Sekaric, J. [Kansas U.; Toback, D. [Texas A-M; Van Kooten, R. [Indiana U.; Vellidis, C. [Fermilab; Zivkovic, L. [Clemson U.

    2015-02-27

    We present a comprehensive review of the physics results obtained by the CDF and D0 collaborations up to summer 2014, with emphasis on those achieved in the Run II of the Tevatron collider which delivered a total integrated luminosity of ~10 fb$^{-1}$ at $\\sqrt{s} = 1.96~{\\rm TeV}$. The results are presented in six main physics topics: QCD, Heavy Flavor, Electroweak, Top quark, Higgs boson and searches for New Particles and Interactions. The characteristics of the accelerator, detectors, and the techniques used to achieve these results are also briefly summarized.

  12. Search for MSSM Higgses at the Tevatron

    CERN Document Server

    Connolly, A

    2002-01-01

    We present an overview of searches for MSSM Higgs at the Tevatron, concentrating on searches probing the high tan(beta) region. We discuss the search for A/H -> tau tau which is soon to be completed in the Run I data and review the new tau triggers implemented by CDF and D0 in Run II, which will greatly impact this analysis. We also present the results of a Run I search for A/H bb -> bbbb performed by CDF and highlight expected improvements in this channel by both experiments in Run II.

  13. Emittance growth due to Tevatron flying wires

    Energy Technology Data Exchange (ETDEWEB)

    Syphers, M; Eddy, Nathan

    2004-06-01

    During Tevatron injection, Flying Wires have been used to measure the transverse beam size after each transfer from the Main Injector in order to deduce the transverse emittances of the proton and antiproton beams. This amounts to 36 + 9 = 45 flies of each of 3 wire systems, with an individual wire passing through each beam bunch twice during a single ''fly''. below they estimate the emittance growth induced by the interaction of the wires with the particles during these measurements. Changes of emittance from Flying Wire measurements conducted during three recent stores are compared with the estimations.

  14. Hard Colour Singlet Exchange at the Tevatron

    CERN Document Server

    Cox, Brian; Lonnblad, Leif; Cox, Brian; Forshaw, Jeff; Lonnblad, Leif

    1999-01-01

    We have performed a detailed phenomenological investigation of the hard colour singlet exchange process which is observed at the Tevatron in events which have a large rapidity gap between outgoing jets. We include the effects of multiple interactions to obtain a prediction for the gap survival factor. Comparing the data on the fraction of gap events with the prediction from BFKL pomeron exchange we find agreement provided that a constant value of alpha_s is used in the BFKL calculation. Moreover, the value of alpha_s is in line with that extracted from measurements made at HERA.

  15. Single Top Quarks at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Heinson, Ann P.; /UC, Riverside

    2008-09-01

    After many years searching for electroweak production of top quarks, the Tevatron collider experiments have now moved from obtaining first evidence for single top quark production to an impressive array of measurements that test the standard model in several directions. This paper describes measurements of the single top quark cross sections, limits set on the CKM matrix element |Vtb|, searches for production of single top quarks produced via flavor-changing neutral currents and from heavy W-prime and H+ boson resonances, and studies of anomalous Wtb couplings. It concludes with projections for future expected significance as the analyzed datasets grow.

  16. New diffractive results from the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gallinaro, Michele; /Rockefeller U.

    2005-05-01

    Experimental results in diffractive processes are summarized and a few notable characteristics described in terms of Quantum Chromodynamics. Exclusive dijet production is used to establish a benchmark for future experiments in the quest for diffractive Higgs production at the Large Hadron Collider. Using new data from the Tevatron and dedicated diffractive triggers, no excess over a smooth falling distribution for exclusive dijet events could be found. Stringent upper limits on the exclusive dijet production cross section are presented. The quark/gluon composition of dijet final states is used to provide additional hints on exclusive dijet production.

  17. Longitudinal dynamics and tomography in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Stogin, J. [Princeton Univ., Princeton, NJ (United States); Sen, T. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Moore, R. S. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2012-01-10

    Motivated by the desire to understand the longitudinal effects of beam-beam forces, we study the longitudinal dynamics of protons and anti-protons at injection and top energy in the Tevatron. Multi-turn data of the longitudinal profiles are captured to reveal information about frequencies of oscillation, and changes in the bunch distributions. Tomographic reconstruction is used to create phase space maps which are subsequently used to find the momentum distributions. Changes in these distributions for both proton and anti-proton beams are also followed through the operational cycle. We report too on the details of interesting dynamics and some unexpected findings.

  18. Charm (and Beauty) Production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Rademacker, Jonas; /Bristol U.

    2007-11-01

    The authors present recent results on heavy flavor production at Tevatron Run II for typically {approx} 1 fb{sup -1} of analyzed p{bar p} data at {radical}s = 1.96 TeV. This includes results on single and correlated open charm and bottom cross sections, charm pair production kinematics, J/{psi}, {psi}(2S) and {chi}{sub cJ} cross sections and polarization measurements in J/{psi}, {psi}(2S), {Upsilon}(1S), and {Upsilon}(2S).

  19. Recent Tevatron Results on CP-Violation

    Energy Technology Data Exchange (ETDEWEB)

    Garbincius, Peter H. [Fermilab

    2014-08-27

    Using their full Tevatron Run II data sets, the CDF and D0 Experiments present measurements of CP -violating asymmetries in the charmless decays of bottom baryons Λ0 → pπ-, Λ0 → pK-, and also for B0 → K-π+, B0 → K+π-, b b s Ds → φπ± , and for single muons and like-sign dimuons in pp collisions. Except for the like-sign dimuon asymmetry, these asymmetry measurements are consistent with available predictions of the standard model.

  20. Recent Tevatron Results on CP-Violation

    Energy Technology Data Exchange (ETDEWEB)

    Garbincius, Peter H. [Fermilab

    2014-08-25

    Using their full Tevatron Run II data sets, the CDF and D0 Experiments present measurements of CP-violating asymmetries in the charmless decay of bottom baryons Lambda-b => p pi-, Lambda-b => p K-, and also for Bs0 => K- pi+, B0 => K+ pi-, Ds => phi pi, and for single muons and like-sign dimuons in p-pbar collisions. Except for the like-sign dimuon asymmetry, these asymmetry measurements are consistent with available predictions of the standard model.

  1. Tevatron Results on Heavy Flavor Production and Decay

    Energy Technology Data Exchange (ETDEWEB)

    Scuri, Fabrizio [INFN, Pisa

    2014-09-02

    The most recent results on heavy flavor production and decays from the Tevatron experiments CDF and D0 are summarized and compared with some LHC experiment results. The collected data sample refers to the full Tevatron Run II operation and it corresponds to about 10 inverse fb of integrated luminosity per experiment.

  2. Electroweak, top and bottom physics at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Ukegawa, Fumihiko; /Tsukuba U.

    2004-10-01

    The Tevatron Run-II program has been in progress since 2001, and the CDF and D0 experiments have been operational with upgraded detectors. Coupled with recent improvements in the Tevatron accelerator performance, the experiments have started producing important physics results and measurements. They report these measurements as well as prospects in the near future.

  3. Contact Lenses - A Review

    OpenAIRE

    Dada V; Sharma Rajiv

    1987-01-01

    A review of recent literature on contact lenses shows increasingly more studies on soft contact lenses than PMMA hard lenses The articles on contact lens wear and ulcerative keratitis have highlighted the increased risk of microbial keratitis in contact lens wearers compared to the general population, higher virulence of pathogens isolated and special association of fungi with EWSCL This high risk is due to multiple factors, organism survival in moist lens cases and cleaning solutions, microt...

  4. Gravitational lensing and microlensing

    CERN Document Server

    Mollerach, Silvia

    2002-01-01

    This book provides a comprehensive and self-contained exposition of gravitational lensing phenomena. It presents the up-to-date status of gravitational lensing and microlensing, covering the cosmological applications of the observed lensing by galaxies, clusters and the large scale structures, as well as the microlensing searches in the Local Group and its applications to unveil the nature of the galactic dark matter, the search for planetary objects and the distribution of faint stars in our galaxy. Gravitational Lensing and Microlensing is pitched at the level of the graduate student interes

  5. Contact lenses for children.

    Science.gov (United States)

    Jurkus, J M

    1996-01-01

    Contact lenses for children are used to correct a variety of conditions. This paper reviews fitting of soft, silicone elastimer, and rigid gas-permeable contact lenses for therapeutic treatment of aphakia, anisometropia, myopia, hyperopia, esotropia, irregular astigmatism, and nystagmus. Cosmetic custom designs are described for the treatment of aniridia, albinism, amblyopia, and corneal disfigurement. Working with children and gaining their trust requires inventiveness and patience. Prescribing contact lenses for them requires developing good cooperation between the child, the parents, and the practitioner. The rewards of contact lenses wear for the appropriate pediatric patients include improving not only their vision but also their quality of life.

  6. QCD, Tevatron results and LHC prospects

    Energy Technology Data Exchange (ETDEWEB)

    Elvira, V.Daniel; /Fermilab

    2008-08-01

    We present a summary of the most recent measurements relevant to Quantum Chromodynamics (QCD) delivered by the D0 and CDF Tevatron experiments by May 2008. CDF and D0 are moving toward precision measurements of QCD based on data samples in excess of 1 fb-1. The inclusive jet cross sections have been extended to forward rapidity regions and measured with unprecedented precision following improvements in the jet energy calibration. Results on dijet mass distributions, bbbar dijet production using tracker based triggers, underlying event in dijet and Drell-Yan samples, inclusive photon and diphoton cross sections complete the list of measurements included in this paper. Good agreement with pQCD within errors is observed for jet production measurements. An improved and consistent theoretical description is needed for photon+jets processes. Collisions at the LHC are scheduled for early fall 2008, opening an era of discoveries at the new energy frontier, 5-7 times higher than that of the Tevatron.

  7. Bucket shaking stops bunch dancing in Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Burov, A.; Tan, C.Y.; /Fermilab

    2011-03-01

    Bunches in Tevatron are known to be longitudinally unstable: their collective oscillations, also called dancing bunches, persist without any signs of decay. Typically, a damper is used to stop these oscillations, but recently, it was theoretically predicted that the oscillations can be stabilized by means of small bucket shaking. Dedicated measurements in Tevatron have shown that this method does stop the dancing. According to predictions of Refs. [2,3], the flattening of the bunch distribution at low amplitudes should make the bunch more stable against LLD. An experiment has been devised to flatten the distribution by modulating the RF phase at the low-amplitude synchrotron frequency for a few degrees of amplitude. These beam studies show that stabilisation really happens. After several consecutive shakings, the dancing disappears and the resulting bunch profile becomes smoother at the top. Although not shown in this report, sometimes a little divot forms at the centre of the distribution. These experiments confirm that resonant RF shaking flattens the bunch distribution at low amplitudes, and the dancing stops.

  8. HFiTT - Higgs Factory in Tevatron Tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Weiren [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Mourou, Gerard [Ecole Polytechnique, Palaiseau (France); Solyak, Nikolay [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Tajima, Toshiki [Univ. of California, Irvine, CA (United States); Velasco, Mayda [Northwestern Univ., Evanston, IL (United States)

    2013-05-20

    Among various options for a Higgs factory [1], a photon collider has the distinct advantage of the lowest energy requirement for an electron beam. This advantage is especially important for a circular Higgs factory, in which the synchrotron radiation power increases to the fourth power of the electron energy. For an e+e- collider, the minimum required energy per beam is 120 GeV, while for a photon collider it is 80 GeV. The corresponding ratio of synchrotron radiation power is 5 to 1. This makes it possible to consider building a photon collider at Fermilab, which will be named HFiTT, or Higgs Factory in Tevatron Tunnel. The layout is shown in Figure 1. A photon collider is based on Inverse Compton Scattering (ICS) by shooting a low energy (~3.5 eV) laser beam into a high energy (10s of GeV) electron beam to generate a back-scattered high energy (10s of GeV) photon beam for collision. The cross section for γγ → H is large and comparable to e+e- → ZH (~200 fb). Since this is an s-channel resonance, the required photon energy is low (63 GeV), corresponding to 80 GeV for an electron beam. Our design goal is 10,000 Higgs per year. If we look to the far future of electron collider technology, very high gradient acceleration techniques such as plasma wakefield acceleration are asymmetric between electrons and positrons. It is therefore important to develop a technology that will allow physicists to accelerate electrons only and still access annihilation reactions with precisely understood point-like interactions. The photon collider fills this need. This project will not only carry out important measurements of the Higgs boson properties but will also demonstrate the unique technologies needed to construct photon collider experiments at higher energies.

  9. Update on scleral lenses.

    Science.gov (United States)

    Jacobs, Deborah S

    2008-07-01

    Scleral rigid gas-permeable lenses play an important and underappreciated role in the treatment of corneal disease. This review provides an update on scleral rigid gas-permeable lenses for the visual rehabilitation of ectasia and irregular astigmatism, and an update on scleral rigid gas-permeable lenses in the therapy of ocular surface disease. Several series and one case report present advances in the treatment of ocular surface disease with scleral rigid gas-permeable lenses. In addition, there are two reports describing one center's consecutive case experience using modern scleral lens design, predominantly in patients with ectasia and postkeratoplasty astigmatism. Finally, a comprehensive article reviewing the history and principles behind current scleral rigid gas-permeable lenses, with particular attention to the use of scleral rigid gas-permeable lenses in the management of ocular surface disorders was published. Clinicians who treat patients with ocular surface disease should be aware of scleral rigid gas-permeable lenses as a therapeutic option for their patients. Advances in lens design make scleral rigid gas-permeable lenses a practical option for an increasing number and variety of patients with corneal disease.

  10. Contact Lenses - A Review

    Directory of Open Access Journals (Sweden)

    Dada V

    1987-01-01

    Full Text Available A review of recent literature on contact lenses shows increasingly more studies on soft contact lenses than PMMA hard lenses The articles on contact lens wear and ulcerative keratitis have highlighted the increased risk of microbial keratitis in contact lens wearers compared to the general population, higher virulence of pathogens isolated and special association of fungi with EWSCL This high risk is due to multiple factors, organism survival in moist lens cases and cleaning solutions, microtrauma to the corneal epithelium by repeated insertion and removal, corneal hypoxia and lens deposits in soft lenses Special problems of tonometry in eyes with bandage soft lenses and contact lens sterilization have been studied and useful suggestions have come forth from the authors

  11. Diagnostics of the Fermilab Tevatron using an AC dipole

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Ryoichi [Univ. of Texas, Austin, TX (United States)

    2008-08-01

    The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of the beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.

  12. Accelerator physics at the Tevatron collider

    CERN Document Server

    Shiltsev, Vladimir

    2014-01-01

    This book presents the developments in accelerator physics and technology implemented at the Tevatron proton-antiproton collider, the world’s most powerful accelerator for almost twenty years prior to the completion of the Large Hadron Collider. The book covers the history of collider operation and upgrades, novel arrangements of beam optics and methods of orbit control, antiproton production and cooling, beam instabilities and feedback systems, halo collimation, and advanced beam instrumentation. The topics discussed show the complexity and breadth of the issues associated with modern hadron accelerators, while providing a systematic approach needed in the design and construction of next generation colliders. This book is a valuable resource for researchers in high energy physics and can serve as an introduction for students studying the beam physics of colliders.

  13. Top Quark Physics at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Andreas W. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). Particle Physics Division

    2015-05-21

    An overview of recent top quark measurements using the full Run II data set of CDF or D0 at the Tevatron is presented. Results are complementary to the ones at the LHC. Recent measurements of the production cross section of top quarks in strong and electroweak production and of top quark production asymmetries are presented. The latter includes the measurement of the tt-bar production asymmetry by D0 in the dilepton decay channel. Within their uncertainties the results from all these measurements agree with their respective Standard Model expectation. Finally latest updates on measurements of the top quark mass are discussed, which at the time of the conference are the most precise determinations.

  14. QCD at the Tevatron: Jets and fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    V. Daniel Elvira

    2001-09-27

    At the Fermilab Tevatron energies, ({radical} s=1800 GeV and {radical} s = 630 GeV), jet production is the dominant process. During the period 1992-1996, the D0 and CDF experiments accumulated almost 100 pb{sup -1} of data and performed the most accurate jet production measurements up to this date. These measurements and the NLO-QCD theoretical predictions calculated during the last decade, have improved our understanding of QCD, our knowledge of the proton structure, and pushed the limit to the scale associated with quark compositeness to 2.4-2.7 TeV. In this paper, we present the most recent published and preliminary measurements on jet production and fragmentation by the D0 and CDF collaborations.

  15. The TEVATRON Phase 1 Project, December, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1979-12-01

    This report describes the "Tevatron Phase I" project at the Fermi National Accelerator Laboratory. The project follows research and development efforts and the earlier Energy Saver project. The R & D work has led to the development and fabrication of superconducting accelerator magnets and installation of a test string of magnets in A sector of the MainRing tunnel. The Energy Saver project, authorized in FY79 and now in progress, includes construction of a complete ring of superconducting magnets and their installation in the Main-Ring tunnel. The project includes refrigeration and rf equipment adequate for sustained operation of the ring at a peak energy of 500 GeV, making use of the existing experimental areas....

  16. Scientific Opportunity: the Tevatron and the LHC

    CERN Multimedia

    2010-01-01

    The press makes much of the competition between CERN’s LHC and Fermilab’s Tevatron in the search for the Higgs boson. This competitive aspect is real, and probably adds spice to the scientific exploration, but for us such reporting often feels like spilling the entire pepper shaker over a fine meal. The media’s emphasis on competition obscures the more important substance of our long-standing collaboration in scientific discovery.   Our laboratories and our communities have worked together for decades. Europeans have contributed greatly to the Tevatron’s many successes, including the discovery of the top quark, the discovery of fast oscillations in the decay of strange B mesons and the many searches for new phenomena. Americans have contributed to many programs at CERN, notably the extraordinary precision measurements of LEP, and more recently construction of the LHC accelerator and detectors. Fermilab scientists played a vital role throughout 2009 in...

  17. Inverting Gravitational Lenses

    Science.gov (United States)

    Newbury, P. R.; Spiteri, R. J.

    2002-02-01

    Gravitational lensing provides a powerful tool to study a number of fundamental questions in astrophysics. Fortuitously, one can begin to explore some non-trivial issues associated with this phenomenon without a lot of very sophisticated mathematics, making an elementary treatment of this topic tractable even to senior undergraduates. In this paper, we give a relatively self-contained outline of the basic concepts and mathematics behind gravitational lensing as a recent and exciting topic for courses in mathematical modeling or scientific computing. To this end, we have designed and made available some interactive software to aid in the simulation and inversion of gravitational lenses in a classroom setting.

  18. Stress-Detection Lenses

    Science.gov (United States)

    1996-01-01

    An Ames Research Center scientist invented an infrared lens used in sunglasses to filter out ultraviolet rays. This product finds its origins in research for military enemy detection. Through a Space Act Agreement, Optical Sales Corporation introduced the Hawkeye Lenses not only as sunglasses but as plant stress detection lenses. The lenses enhance the stressed part of the leaf, which has less chlorophyll than healthy leaves, through dyes that filter out certain wavelengths of light. Plant stress is visible earlier, at a stage when something can be done to save the plants.

  19. Tevatron The Cinderella story or the art of collider

    CERN Document Server

    CERN. Geneva

    2007-01-01

    The Tevatron Collider at Fermilab (Batavia, IL, USA) is the world's highest energy particle collider at 1.8TeV c.m.e. The machine was a centerpiece of the US and world's High Energy Physics for many years. Currently, the Tevatron is in the last years of its operation in so-called Run II which started 2001 and is tentatively scheduled to end in 2010. In this lecture series, we'll try to learn from the exciting story of the Tevatron Collider Run II: the story of long preparations, great expectations, initial difficulties, years of "blood and sweat", continuous upgrades, exceeding its goals, high emotions, tune-up of accelerator organization for "combat fighting". The lectures will cover Introduction to the Tevatron, its history and Run II; "Plumbing" Issues; Beam Physics Issues; Luminosity Progress; Organization of Troops and Lessons for LHC.

  20. Beyond the Standard Model at the Tevatron and the LHC

    OpenAIRE

    Perelstein, Maxim

    2008-01-01

    This contribution contains a brief review of several scenarios for physics beyond the Standard Model at the energy scales accessible to experiments at the Tevatron and the LHC, focusing on their experimental signatures.

  1. Entwicklungsarbeit am Spurendetektor fur das CDF Experiment am Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Frank [Univ. of Karlsruhe (TH) (Germany)

    2000-02-01

    Silicon, the element, which revolutionized the development of electronics, is known as an important and multiusable material, dominating todays electronic technology. It's properties are well investigated and today well known. Silicon is used in solar cells, computers and telecommunications. Since the Sixties semiconductors have been used as particle detectors. Initially they were operated in fixed- target experiments as calorimeters and as detectors with a high precision track reconstruction. Since the Eighties they are widely used in collider experiments as silicon microstrip or silicon pixel detectors near the primary vertex. Silicon sensors have a very good intrinsic energy resolution: for every 3.6 eV released by a particle crossing the medium, one electron-hole pair is produced. Compared to 30 eV required to ionize a gas molecule in a gaseous detector, one gets 10 times the number of particles. The average energy loss and high ionized particle number with 390 e V / μm ~ 108 (electron - hole pairs)/ μm is effectively high due to the high density of silicon. These detectors allow a high precision reconstruction of tracks, primary and secondary vertices, which are especially important for b flavour tagging. The Tevatron and its detectors are being upgraded for the next data taking run starting in 2001 (RUN II). The Collider Detector at Fermilab (CDF) [2] for the upcoming Run II and its upgraded components are described in chapter 2. The main upgrade project is the design and construction of a completely new inner tracking system.

  2. Calculation of the transverse kicks generated by the bends of a hollow electron lens

    Energy Technology Data Exchange (ETDEWEB)

    Stancari, Giulio

    2014-03-25

    Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam in high-energy accelerators. They were used in the Fermilab Tevatron collider for abort-gap clearing, beam-beam compensation, and halo scraping. A beam-beam compensation scheme based upon electron lenses is currently being implemented in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. This work is in support of a conceptual design of hollow electron beam scraper for the Large Hadron Collider. It also applies to the implementation of nonlinear integrable optics with electron lenses in the Integrable Optics Test Accelerator at Fermilab. We consider the axial asymmetries of the electron beam caused by the bends that are used to inject electrons into the interaction region and to extract them. A distribution of electron macroparticles is deposited on a discrete grid enclosed in a conducting pipe. The electrostatic potential and electric fields are calculated using numerical Poisson solvers. The kicks experienced by the circulating beam are estimated by integrating the electric fields over straight trajectories. These kicks are also provided in the form of interpolated analytical symplectic maps for numerical tracking simulations, which are needed to estimate the effects of the electron lens imperfections on proton lifetimes, emittance growth, and dynamic aperture. We outline a general procedure to calculate the magnitude of the transverse proton kicks, which can then be generalized, if needed, to include further refinements such as the space-charge evolution of the electron beam, magnetic fields generated by the electron current, and longitudinal proton dynamics.

  3. Design Report Tevatron 1 Project (Second Printing November 1982)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1982-10-01

    This report describes the design of the Tevatron I Project, which will enable Fermilab to produce proton-antiproton collisions in the Tevatron accelerator. Center-of-mass energies near 2 TeV, by far the highest available anywhere in the world for high-energy physics research until at least the decade of the 1990's, will provide enormous opportunities for exciting new physics.

  4. Operation and physics potential of Tevatron Run 2

    Energy Technology Data Exchange (ETDEWEB)

    John Womersley

    2001-12-07

    The Tevatron Run 2 has begun. The Tevatron program in the next six years offers a real opportunity to significantly advance our understanding of the fundamental properties of the universe. It is an exciting, challenging program that goes straight to the highest priorities of high energy physics worldwide. The accelerator and detectors are being commissioned and seem to be performing well. We anticipate first physics results in the summer of 2002.

  5. Gravitational lensing of quasars

    CERN Document Server

    Eigenbrod, Alexander

    2013-01-01

    The universe, in all its richness, diversity and complexity, is populated by a myriad of intriguing celestial objects. Among the most exotic of them are gravitationally lensed quasars. A quasar is an extremely bright nucleus of a galaxy, and when such an object is gravitationally lensed, multiple images of the quasar are produced – this phenomenon of cosmic mirage can provide invaluable insights on burning questions, such as the nature of dark matter and dark energy. After presenting the basics of modern cosmology, the book describes active galactic nuclei, the theory of gravitational lensing, and presents a particular numerical technique to improve the resolution of astronomical data. The book then enters the heart of the subject with the description of important applications of gravitational lensing of quasars, such as the measurement of the famous Hubble constant, the determination of the dark matter distribution in galaxies, and the observation of the mysterious inner parts of quasars with much higher r...

  6. W mass and Triple Gauge Couplings at Tevatron

    Directory of Open Access Journals (Sweden)

    Pétroff Pierre

    2013-05-01

    Full Text Available The W mass is a crucial parameter in the Standard Model (SM of particle physics, providing constraints on the mass of the Higgs boson as well as on new physics models via quantum loop corrections. On the other hand, any deviation of the triple gauge boson couplings (TGC from their values predicted by the SM would be also an indication for new physics. We present recent measurements on W boson mass and searches for anomalous TGC (aTGC in Wγ, Zγ, WW, WZ and ZZ at Fermilab Tevatron both by CDF and DØ Collaborations. The CDF Collaboration has measured the W boson mass using data corresponding to 2.2 fb−1 of integrated luminosity. The measurement, performed using electron and muon decays of W boson, yields a mass of MW = 80387 ± 19 MeV. The DØ Collaboration has measured MW = 80367 ± 26 MeV with data corresponding to 4.3 fb−1 of integrated luminosity in the channel W → ev. The combination with an earlier DØ result, using independant data sample at 1 fb−1 of integrated luminosity, yields MW = 80375 ± 23 MeV. The limits on anomalous TGCs parameters are consistent with the SM expectations.

  7. The Effects of combined HERA and recent Tevatron W - > l $\

    CERN Document Server

    Thorne, R.S.; Stirling, W.J.; Watt, G.

    2010-01-01

    We examine the effect of including the `combined' HERA structure function data in the MSTW global fit for parton distribution functions (PDFs). The combined neutral-current HERA data have a significant, if not dramatic, effect, of up to 2--3% at NLO for Z boson and Higgs production at the Tevatron and LHC, and a generally slightly smaller effect, particularly on LHC processes, at NNLO. This is an amount comparable, or less than, the typical PDF uncertainties, and hence we do not intend to release an imminent update to the MSTW 2008 fit. We also investigate the consistency with the recent D0 data on electron and muon charge asymmetry from W decays and the direct CDF measurement of the W charge asymmetry. The D0 lepton charge asymmetry data imply a fairly large change to the down-quark distribution and/or large nuclear corrections to be applied when fitting to deuterium structure function data, while the CDF W charge asymmetry data are more consistent with the existing PDFs. However, it is difficult to reconcil...

  8. Higgs boson studies at the Tevatron

    Science.gov (United States)

    Aaltonen, T.; Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Askew, A.; Atkins, S.; Auerbach, B.; Augsten, K.; Aurisano, A.; Avila, C.; Azfar, F.; Badaud, F.; Badgett, W.; Bae, T.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barbaro-Galtieri, A.; Barberis, E.; Baringer, P.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartlett, J. F.; Bartos, P.; Bassler, U.; Bauce, M.; Bazterra, V.; Bean, A.; Bedeschi, F.; Begalli, M.; Behari, S.; Bellantoni, L.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Bhatti, A.; Bland, K. R.; Blazey, G.; Blessing, S.; Bloom, K.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brandt, A.; Brandt, O.; Brigliadori, L.; Brock, R.; Bromberg, C.; Bross, A.; Brown, D.; Brucken, E.; Budagov, J.; Bu, X. B.; Budd, H. S.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buszello, C. P.; Butti, P.; Buzatu, A.; Calamba, A.; Camacho-Pérez, E.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Casey, B. C. K.; Castilla-Valdez, H.; Castro, A.; Catastini, P.; Caughron, S.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Cho, S. W.; Choi, S.; Chokheli, D.; Choudhary, B.; Cihangir, S.; Ciocci, M. A.; Claes, D.; Clark, A.; Clarke, C.; Clutter, J.; Convery, M. E.; Conway, J.; Cooke, M.; Cooper, W. E.; Corbo, M.; Corcoran, M.; Cordelli, M.; Couderc, F.; Cousinou, M.-C.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; Cutts, D.; d'Ascenzo, N.; Das, A.; Datta, M.; Davies, G.; De Barbaro, P.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Demortier, L.; Deninno, M.; Denisov, D.; Denisov, S. P.; d'Errico, M.; Desai, S.; Deterre, C.; DeVaughan, K.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dittmann, J. R.; Dominguez, A.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Ebina, K.; Edgar, R.; Edmunds, D.; Elagin, A.; Ellison, J.; Elvira, V. D.; Enari, Y.; Erbacher, R.; Errede, S.; Esham, B.; Eusebi, R.; Evans, H.; Evdokimov, V. N.; Facini, G.; Farrington, S.; Fauré, A.; Feng, L.; Ferbel, T.; Fernández Ramos, J. P.; Fiedler, F.; Field, R.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Flanagan, G.; Forrest, R.; Fortner, M.; Fox, H.; Franklin, M.; Freeman, J. C.; Frisch, H.; Fuess, S.; Funakoshi, Y.; Garcia-Bellido, A.; García-González, J. A.; Garfinkel, A. F.; Garosi, P.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gerberich, H.; Gerchtein, E.; Gershtein, Y.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Ginther, G.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Golovanov, G.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Grinstein, S.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grosso-Pilcher, C.; Group, R. C.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Guimaraes da Costa, J.; Gutierrez, G.; Gutierrez, P.; Hahn, S. R.; Haley, J.; Han, J. Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, M.; Harel, A.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hauptman, J. M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Hong, Z.; Hopkins, W.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A. S.; Ivanov, A.; Jabeen, S.; Jaffré, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E. J.; Jeong, M. S.; Jesik, R.; Jiang, P.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K. K.; Joshi, J.; Jun, S. Y.; Jung, A. W.; Junk, T. R.; Juste, A.; Kajfasz, E.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Karmanov, D.; Kasmi, A.; Kato, Y.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Knoepfel, K.; Kohli, J. M.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kozelov, A. V.; Kraus, J.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kumar, A.; Kupco, A.; Kurata, M.; Kurča, T.; Kuzmin, V. A.; Laasanen, A. T.; Lammel, S.; Lammers, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lebrun, P.; Lee, H. S.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J. D.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Limosani, A.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipeles, E.; Lipton, R.; Lister, A.; Liu, H.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A. L.; Lys, J.; Lysak, R.; Maciel, A. K. A.; Madar, R.; Madrak, R.; Maestro, P.; Magaña-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V. L.; Manca, G.; Manousakis-Katsikakis, A.; Mansour, J.; Margaroli, F.; Marino, P.; Martínez, M.; Martínez-Ortega, J.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McGivern, C. L.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Mesropian, C.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N. K.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Nett, J.; Neu, C.; Neustroev, P.; Nguyen, H. T.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Osta, J.; Pagliarone, C.; Pal, A.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parashar, N.; Parihar, V.; Park, S. K.; Parker, W.; Partridge, R.; Parua, N.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.-A.; Podstavkov, V. M.; Pondrom, L.; Popov, A. V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Ranjan, N.; Ratoff, P. N.; Razumov, I.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodriguez, T.; Rolli, S.; Rominsky, M.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sajot, G.; Sakumoto, W. K.; Sakurai, Y.; Sánchez-Hernández, A.; Sanders, M. P.; Santi, L.; Santos, A. S.; Sato, K.; Savage, G.; Saveliev, V.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schmidt, E. E.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S. Z.; Shary, V.; Shaw, S.; Shchukin, A. A.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Sinervo, P.; Skubic, P.; Slattery, P.; Sliwa, K.; Smirnov, D.; Smith, J. R.; Snider, F. D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; Stancari, M.; St. Denis, R.; Stark, J.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Stoyanova, D. A.; Strauss, M.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V. V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.-T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Vázquez, F.; Velev, G.; Vellidis, C.; Verkheev, A. Y.; Vernieri, C.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vilanova, D.; Vilar, R.; Vizán, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wahl, H. D.; Wallny, R.; Wang, S. M.; Wang, M. H. L. S.; Wang, R.-J.; Warburton, A.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W. C., III; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Williams, M. R. J.; Wilson, G. W.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfe, H.; Wood, D. R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yeh, G. P.; Yi, K.; Yin, H.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S. W.; Yu, G. B.; Yu, I.; Yu, J. M.; Zanetti, A.; Zeng, Y.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.

    2013-09-01

    We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90-200GeV/c2 produced in the gluon-gluon fusion, WH, ZH, tt¯H, and vector boson fusion processes, and decaying in the H→bb¯, H→W+W-, H→ZZ, H→τ+τ-, and H→γγ modes. The data correspond to integrated luminosities of up to 10fb-1 and were collected at the Fermilab Tevatron in pp¯ collisions at s=1.96TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140GeV/c2. The local significance corresponds to 3.0 standard deviations at mH=125GeV/c2, consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for H→bb¯, H→W+W-, H→τ+τ-, and H→γγ. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125GeV/c2.

  9. Higgs Boson Studies at the Tevatron

    CERN Document Server

    Aaltonen, T.; Abbott, B.; Acharya, B.S.; Adams, M.; Adams, T.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Askew, A.; Atkins, S.; Auerbach, B.; Augsten, K.; Aurisano, A.; Avila, C.; Azfar, F.; Badaud, F.; Badgett, W.; Bae, T.; Bagby, L.; Baldin, B.; Bandurin, D.V.; Banerjee, S.; Barbaro-Galtieri, A.; Barberis, E.; Baringer, P.; Barnes, V.E.; Barnett, B.A.; Barria, P.; Bartlett, J.F.; Bartos, P.; Bassler, U.; Bauce, M.; Bazterra, V.; Bean, A.; Bedeschi, F.; Begalli, M.; Behari, S.; Bellantoni, L.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Beri, S.B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besancon, M.; Beuselinck, R.; Bhat, P.C.; Bhatia, S.; Bhatnagar, V.; Bhatti, A.; Bland, K.R.; Blazey, G.; Blessing, S.; Bloom, K.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boehnlein, A.; Boline, D.; Boos, E.E.; Borissov, G.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brandt, A.; Brandt, O.; Brigliadori, L.; Brock, R.; Bromberg, C.; Bross, A.; Brown, D.; Brucken, E.; Budagov, J.; Bu, X.B.; Budd, H.S.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buszello, C.P.; Butti, P.; Buzatu, A.; Calamba, A.; Camacho-Perez, E.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Casey, B.C.K.; Castilla-Valdez, H.; Castro, A.; Catastini, P.; Caughron, S.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chakrabarti, S.; Chakraborty, D.; Chan, K.M.; Chandra, A.; Chapon, E.; Chen, G.; Chen, Y.C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Cho, S.W.; Choi, S.; Chokheli, D.; Choudhary, B.; Cihangir, S.; Ciocci, M.A.; Claes, D.; Clark, A.; Clarke, C.; Clutter, J.; Convery, M.E.; Conway, J.; Cooke, M.; Cooper, W.E.; Corbo, M.; Corcoran, M.; Cordelli, M.; Couderc, F.; Cousinou, M.C.; Cox, C.A.; Cox, D.J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; Cutts, D.; d'Ascenzo, N.; Das, A.; Datta, M.; Davies, G.; de Barbaro, P.; de Jong, S.J.; De La Cruz-Burelo, E.; Deliot, F.; Demina, R.; Demortier, L.; Deninno, M.; Denisov, D.; Denisov, S.P.; d'Errico, M.; Desai, S.; Deterre, C.; DeVaughan, K.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Diehl, H.T.; Diesburg, M.; Ding, P.F.; Dittmann, J.R.; Dominguez, A.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Dubey, A.; Dudko, L.V.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Ebina, K.; Edgar, R.; Edmunds, D.; Elagin, A.; Ellison, J.; Elvira, V.D.; Enari, Y.; Erbacher, R.; Errede, S.; Esham, B.; Eusebi, R.; Evans, H.; Evdokimov, V.N.; Facini, G.; Farrington, S.; Faure, A.; Feng, L.; Ferbel, T.; Fernandez Ramos, J.P.; Fiedler, F.; Field, R.; Filthaut, F.; Fisher, W.; Fisk, H.E.; Flanagan, G.; Forrest, R.; Fortner, M.; Fox, H.; Franklin, M.; Freeman, J.C.; Frisch, H.; Fuess, S.; Funakoshi, Y.; Garcia-Bellido, A.; Garcia-Gonzalez, J.A.; Garcia-Guerra, G.A.; Garfinkel, A.F.; Garosi, P.; Gavrilov, V.; Geng, W.; Gerber, C.E.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C.M.; Ginther, G.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Golovanov, G.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; Gonzalez Lopez, O.; Gorelov, I.; Goshaw, A.T.; Goulianos, K.; Gramellini, E.; Grannis, P.D.; Greder, S.; Greenlee, H.; Grenier, G.; Grinstein, S.; Gris, Ph.; Grivaz, J.F.; Grohsjean, A.; Grosso-Pilcher, C.; Group, R.C.; Grunendahl, S.; Grunewald, M.W.; Guillemin, T.; Guimaraes da Costa, J.; Gutierrez, G.; Gutierrez, P.; Hahn, S.R.; Haley, J.; Han, J.Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, M.; Harel, A.; Harr, R.F.; Harrington-Taber, T.; Hatakeyama, K.; Hauptman, J.M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A.P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hildreth, M.D.; Hirosky, R.; Hoang, T.; Hobbs, J.D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Hong, Z.; Hopkins, W.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R.E.; Husemann, U.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A.S.; Ivanov, A.; Jabeen, S.; Jaffre, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E.J.; Jeong, M.S.; Jesik, R.; Jiang, P.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K.K.; Joshi, J.; Jun, S.Y.; Jung, A.W.; Junk, T.R.; Juste, A.; Kajfasz, E.; Kambeitz, M.; Kamon, T.; Karchin, P.E.; Karmanov, D.; Kasmi, A.; Kato, Y.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y.N.; Kilminster, B.; Kim, D.H.; Kim, H.S.; Kim, J.E.; Kim, M.J.; Kim, S.B.; Kim, S.H.; Kim, Y.J.; Kim, Y.K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Knoepfel, K.; Kohli, J.M.; Kondo, K.; Kong, D.J.; Konigsberg, J.; Kotwal, A.V.; Kozelov, A.V.; Kraus, J.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kumar, A.; Kupco, A.; Kurata, M.; Kurca, T.; Kuzmin, V.A.; Laasanen, A.T.; Lammel, S.; Lammers, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lebrun, P.; Lee, Hyeon-Seung; Lee, Hyun Su; Lee, J.S.; Lee, S.W.; Lee, W.M.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J.D.; Li, D.; Li, D.; Li, H.; Li, L.; Li, Q.Z.; Lim, J.K.; Limosani, A.; Lincoln, D.; Linnemann, J.; Lipaev, V.V.; Lipeles, E.; Lipton, R.; Lister, A.; Liu, H.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A.L.; Lys, J.; Lysak, R.; Maciel, A.K.A.; Madar, R.; Madrak, R.; Maestro, P.; Magana-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V.L.; Manca, G.; Manousakis-Katsikakis, A.; Mansour, J.; Margaroli, F.; Marino, P.; Martinez, M.; Martinez-Ortega, J.; Matera, K.; Mattson, M.E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McGivern, C.L.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M.M.; Melnitchouk, A.; Menezes, D.; Mercadante, P.G.; Merkin, M.; Mesropian, C.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N.K.; Moon, C.S.; Moore, R.; Morello, M.J.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Naimuddin, M.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H.A.; Negret, J.P.; Nett, J.; Neu, C.; Neustroev, P.; Nguyen, H.T.; Nigmanov, T.; Nodulman, L.; Noh, S.Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S.H.; Oh, Y.D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Osta, J.; Padilla, M.; Pagliarone, C.; Pal, A.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parashar, N.; Parihar, V.; Park, S.K.; Parker, W.; Partridge, R.; Parua, N.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Petroff, P.; Phillips, T.J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.A.; Podesta-Lerma, P.L.M.; Podstavkov, V.M.; Pondrom, L.; Popov, A.V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Rangel, M.S.; Ranjan, N.; Ratoff, P.N.; Razumov, I.; Redondo Fernandez, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodriguez, T.; Rolli, S.; Rominsky, M.; Ronzani, M.; Roser, R.; Rosner, J.L.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sajot, G.; Sakumoto, W.K.; Sakurai, Y.; Salcido, P.; Sanchez-Hernandez, A.; Sanders, M.P.; Santi, L.; Santos, A.S.; Sato, K.; Savage, G.; Saveliev, V.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R.D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schmidt, E.E.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S.Z.; Shary, V.; Shaw, S.; Shchukin, A.A.; Shears, T.; Shepard, P.F.; Shimojima, M.; Shivpuri, R.K.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Sinervo, P.; Skubic, P.; Slattery, P.; Sliwa, K.; Smirnov, D.; Smith, J.R.; Smith, K.J.; Snider, F.D.; Snow, G.R.; Snow, J.; Snyder, S.; Soldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; Stancari, M.; St. Denis, R.; Stark, J.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Stoyanova, D.A.; Strauss, M.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P.K.; Thom, J.; Thomson, E.; Thukral, V.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V.V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; Van Leeuwen, W.M.; Varelas, N.; Varnes, E.W.; Vasilyev, I.A.; Vazquez, F.; Velev, G.; Vellidis, C.; Verkheev, A.Y.; Vernieri, C.; Vertogradov, L.S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vilanova, D.; Vilar, R.; Vizan, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wahl, H.D.; Wallny, R.; Wang, S.M.; Wang, M.H.L.S.; Wang, R.J.; Warburton, A.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W.C., III; White, A.; Whiteson, D.; Wicke, D.; Wicklund, A.B.; Wilbur, S.; Williams, H.H.; Williams, M.R.J.; Wilson, G.W.; Wilson, J.S.; Wilson, P.; Winer, B.L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfe, H.; Wood, D.R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T.R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U.K.; Yang, Y.C.; Yao, W.M.; Yasuda, T.; Yatsunenko, Y.A.; Ye, W.; Ye, Z.; Yeh, G.P.; Yi, K.; Yin, H.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S.W.; Yu, G.B.; Yu, I.; Yu, J.M.; Zanetti, A.; Zeng, Y.; Zennamo, J.; Zhao, T.G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.

    2013-09-17

    We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90--200 GeV/c^2 produced in the gluon-gluon fusion, WH, ZH, ttbarH, and vector boson fusion processes, and decaying in the H->bbbar, H->W^+W^-, H->ZZ, H->\\tau^+\\tau^-, and H->\\gamma \\gamma\\ modes. The data correspond to integrated luminosities of up to 10 fb^-1 and were collected at the Fermilab Tevatron in ppbar collisions at sqrt(s)=1.96 TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV/c^2. The local significance corresponds to 3.1 standard deviations at m_H=125 GeV/c^2, consistent with the mass of the Higgs boson observed at the LHC. Furthermore, we separately combine searches for H->bbbar, H->W^+W^-, H->\\tau^+\\tau^-, and H->\\gamma \\gamma. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 1...

  10. Plasma surface modification of rigid contact lenses decreases bacterial adhesion.

    Science.gov (United States)

    Wang, Yingming; Qian, Xuefeng; Zhang, Xiaofeng; Xia, Wei; Zhong, Lei; Sun, Zhengtai; Xia, Jing

    2013-11-01

    Contact lens safety is an important topic in clinical studies. Corneal infections usually occur because of the use of bacteria-carrying contact lenses. The current study investigated the impact of plasma surface modification on bacterial adherence to rigid contact lenses made of fluorosilicone acrylate materials. Boston XO and XO2 contact lenses were modified using plasma technology (XO-P and XO2-P groups). Untreated lenses were used as controls. Plasma-treated and control lenses were incubated in solutions containing Staphylococcus aureus or Pseudomonas aeruginosa. MTT colorimetry, colony-forming unit counting method, and scanning electron microscopy were used to measure bacterial adhesion. MTT colorimetry measurements showed that the optical density (OD) values of XO-P and XO2-P were significantly lower than those of XO and XO2, respectively, after incubation with S. aureus (P plasma technology in contact lens surface modification.

  11. Contact Lenses in the Laboratory.

    Science.gov (United States)

    Kingston, David W.

    1981-01-01

    Summarizes results of a three-item questionnaire returned by 43 Michigan institutions expressing views on wearing contact lenses in chemical laboratories. Questions focused on eye protection, type of protection, and use of contact lenses. (SK)

  12. Localized defects in ophthalmic lenses.

    Science.gov (United States)

    Stroud, J S

    1989-03-01

    Ophthalmic lenses made from glass, hard resin, and polycarbonate are inspected with a shadowgraph to determine the nature, frequency, and severity of localized defects, including power aberrations. The most common localized defects are scratches and pits left by incomplete polishing and localized power aberrations caused by variations in the thickness of scratch-resistant coatings. Localized defects are more likely in polycarbonate lenses than in glass or hard resin lenses. The compliance of lenses with standards that limit localized defects is discussed.

  13. Cosmology with strong lensing systems

    Science.gov (United States)

    Biesiada, Marek

    2017-08-01

    Strong gravitational lensing has now developed into a mature tool for investigating galactic structure and dynamics as well as cosmological models. In this lecture the phenomenon of strong gravitational lensing, its history and applications are reviewed with an emphasis on the recent ideas developed by the author. Expected massive discoveries of strong lensing galactic scale systems in forthcoming projects like Euclid or LSST herald the bright future of gravitational lensing in cosmology.

  14. Overview of Beam-Beam Effects in the Tevatron

    CERN Document Server

    Shiltsev, V.

    2014-01-01

    For almost a quarter of a century the Tevatron proton-antiproton collider was the centrepiece of the world's high-energy physics program, from the start of operation in December 1985 until it was overtaken by the LHC in 2011. The initial design luminosity of the Tevatron was 1030 cm-2 s-1; however, as a result of two decades of upgrades, the accelerator has been able to deliver 430-times higher luminosities to each of two high-luminosity experiments, Collider Detector at Fermilab (CDF) and D0. On the way to record high luminosities, many issues related to the electromagnetic beam-beam interaction of colliding beams have been addressed. Below we present a short overview of the beam-beam effects in the Tevatron.

  15. Tevatron-for-LHC Report of the QCD Working Group

    Energy Technology Data Exchange (ETDEWEB)

    Albrow, Michael G.; Begel, M.; Bourilkov, D.; Campanelli, M.; Chlebana, F.; De Roeck, A.; Dittmann, J.R.; Ellis, S.D.; Field, B.; Field, R.; Gallinaro, M.; /Fermilab

    2006-10-01

    The experiments at Run 2 of the Tevatron have each accumulated over 1 fb{sup -1} of high-transverse momentum data. Such a dataset allows for the first precision (i.e. comparisons between theory and experiment at the few percent level) tests of QCD at a hadron collider. While the Large Hadron Collider has been designed as a discovery machine, basic QCD analyses will still need to be performed to understand the working environment. The Tevatron-for-LHC workshop was conceived as a communication link to pass on the expertise of the Tevatron and to test new analysis ideas coming from the LHC community. The TeV4LHC QCD Working Group focused on important aspects of QCD at hadron colliders: jet definitions, extraction and use of Parton Distribution Functions, the underlying event, Monte Carlo tunes, and diffractive physics. This report summarizes some of the results achieved during this workshop.

  16. Rare b decays and CP violation at the Tevatron

    Science.gov (United States)

    Ristori, Luciano

    2012-03-01

    The experiments at the Tevatron, CDF and D0, have access to one of the world's largest samples of charm and beauty hadrons decays. These provide information competitive and complementary to that from dedicated flavor facilities. With the analysis of the full Run II data sample, this successful program has now reached its maturity. I review recent Tevatron flavor physics results, focusing on those that are specifically sensitive to departures from the Standard Model, such as searches for rare B decays, measurements of CP-violation in charm, and bottom-strange decays.

  17. Critical Speed Measurements in the Tevatron Cold Compressors

    Science.gov (United States)

    DeGraff, B.; Bossert, R.; Martinez, A.; Soyars, W. M.

    2006-04-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high energy operations. Nominal operating range for these compressors is 43,000 to 85,000 rpm. Past foil bearing failures prompted investigation to determine if critical speeds for operating compressors fall within operating range. Data acquisition hardware and software settings will be discussed for measuring liftoff, first critical and second critical speeds. Several tests provided comparisons between an optical displacement probe and accelerometer measurements. Vibration data and analysis of the 20 Tevatron ring cold compressors will be presented.

  18. Searches for the standard model Higgs boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Dorigo, Tommaso; /Padua U.

    2005-05-01

    The CDF and D0 experiments at the Tevatron have searched for the Standard Model Higgs boson in data collected between 2001 and 2004. Upper limits have been placed on the production cross section times branching ratio to b{bar b} pairs or W{sup +}W{sup -} pairs as a function of the Higgs boson mass. projections indicate that the Tevatron experiments have a chance of discovering a M{sub H} = 115 GeV Higgs with the total dataset foreseen by 2009, or excluding it at 95% C.L. up to a mass of 135 GeV.

  19. Biocompatibility of Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Pelin Özyol

    2017-08-01

    Full Text Available The performance of an intraocular lens is determined by several factors such as the surgical technique, surgical complications, intraocular lens biomaterial and design, and host reaction to the lens. The factor indicating the biocompatibility of an intraocular lens is the behavior of inflammatory and lens epithelial cells. Hence, the biocompatibility of intraocular lens materials is assessed in terms of uveal biocompatibility, based on the inflammatory foreign-body reaction of the eye against the implant, and in terms of capsular biocompatibility, determined by the relationship of the intraocular lens with residual lens epithelial cells within the capsular bag. Insufficient biocompatibility of intraocular lens materials may result in different clinical entities such as anterior capsule opacification, posterior capsule opacification, and lens epithelial cell ongrowth. Intraocular lenses are increasingly implanted much earlier in life in cases such as refractive lens exchange or pediatric intraocular lens implantation after congenital cataract surgery, and these lenses are expected to exhibit maximum performance for many decades. The materials used in intraocular lens manufacture should, therefore, ensure long-term uveal and capsular biocompatibility. In this article, we review the currently available materials used in the manufacture of intraocular lenses, especially with regard to their uveal and capsular biocompatibility, and discuss efforts to improve the biocompatibility of intraocular lenses.

  20. Glasses and Contact Lenses

    Science.gov (United States)

    ... really fun part of new glasses or contact lenses is how well you can see. They can make your whole world look better! Reviewed by: Jonathan H. Salvin, ... Abrasions Why Do Eyes Water? What It's Like to Be Color Blind Contact ...

  1. Effects of refrigeration on daily microbial bioburden of hydrogel lenses.

    Science.gov (United States)

    Lapple, W J; Snyder, A C; Tuovinen, O H

    1987-03-01

    Microbial bioburden of contact lenses was evaluated in connection with lens care by refrigeration. Subjects wore new hydrogel contact lenses for approximately 8 hours. The microbial bioburden initially and after an overnight refrigeration of the lens was evaluated with the use of viable counts on three different media. No major changes in viable counts were observed resulting from this method of storage. Scanning electron microscopy indicated the presence of foreign material on both new and worn lenses, presumed to be debris from lens manufacture and mucoid deposits from daily wear. Microbial colonization was not apparent and single bacterial cells could not be discerned on the micrographs.

  2. Measurements of beam halo diffusion and population density in the Tevatron and in the Large Hadron Collider

    CERN Document Server

    Stancari, Giulio

    Halo dynamics influences global accelerator performance: beam lifetimes, emittance growth, dynamic aperture, and collimation efficiency. Halo monitoring and control are also critical for the operation of high-power machines. For instance, in the high-luminosity upgrade of the LHC, the energy stored in the beam tails may reach several megajoules. Fast losses can result in superconducting magnet quenches, magnet damage, or even collimator deformation. The need arises to measure the beam halo and to remove it at controllable rates. In the Tevatron and in the LHC, halo population densities and diffusivities were measured with collimator scans by observing the time evolution of losses following small inward or outward collimator steps, under different experimental conditions: with single beams and in collision, and, in the case of the Tevatron, with a hollow electron lens acting on a subset of bunches. After the LHC resumes operations, it is planned to compare measured diffusivities with the known strength of tran...

  3. Searches for standard model Higgs at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Vilar Cortabitarte, Rocio; /Cantabria U., Santander

    2007-04-01

    A summary of the latest results of Standard Model Higgs boson searches from CDF and D0 presented at the DIS 2007 conference is reported in this paper. All analyses presented use 1 fb{sup -1} of Tevatron data. The strategy of the different analyses is determined by the Higgs production mechanism and decay channel.

  4. Searches for Beyond SM Higgs Boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Safonov, A.; /Texas A-M

    2006-05-01

    In the following, the authors describe preliminary results of searches for non-SM higgs bosons at the CDF and D0 experiments. Both experiments use data obtained in p{bar p} collisions at the Tevatron at {radical}s = 1.96 TeV.

  5. High pt jets and photons at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, Cecilia E.; /Illinois U., Chicago

    2005-09-01

    The authors present recent results on high p{sub T} jets and photon production in {bar p}p collisions at a center of mass energy of 1.96 TeV. The measurements were performed by the CDF and D0 collaborations using between 150 and 300 pb{sup -1} of data taken during Run II at the Tevatron.

  6. Race for the Higgs hots up as Tevatron seeks extension

    CERN Multimedia

    Banks, Michael

    2009-01-01

    "With researchers at Cern's Large Hadron Collider (LHC) having circulated protons for the first time since last year's accident, the US Department of Energy (DOE) is requesting $25m so that the Tevatron collider at the Fermi National Accelerator Laboratory in Illinois can run for an extra year until 2011" (0.25 page)

  7. Explaining Tevatron leptons photons missing- T events with ...

    Indian Academy of Sciences (India)

    model prediction, our model is in good agreement with these data because their signal to background efficiency is low at the best-fit point. However, they help to constrain the model away from the best fit point. Keywords. Gauge mediated; Tevatron. 1. Introduction. The CDF experiment has recently discovered an anomaly in ...

  8. Bs data at Tevatron and possible new physics

    Indian Academy of Sciences (India)

    2012-11-15

    Nov 15, 2012 ... Although most of the data from the Tevatron experiments of CDF and DØ, and to a smaller extent, the B factories Belle and BABAR are consistent with the Standard Model (SM), there are some measurements, which show a significant deviation from the SM expecta- tions, and hence point towards new ...

  9. Surge Recovery Techniques for the Tevatron Cold Compressors

    Science.gov (United States)

    Martinez, A.; Klebaner, A. L.; Makara, J. N.; Theilacker, J. C.

    2006-04-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, made by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations. The compressor is designed to pump 60 g/s of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/s and operating speeds between 40 and 95 krpm. Since initial commissioning in 1993, Tevatron transient conditions such as quench recovery have led to multiple-location machine trips as a result of the cold compressors entering the surge regime. Historically, compressors operating at lower inlet pressures and higher speeds have been especially susceptible to these machine trips and it was not uncommon to have multiple compressor trips during large multiple-house quenches. In order to cope with these events and limit accelerator down time, surge recovery techniques have been implemented in an attempt to prevent the compressors from tripping once the machine entered this surge regime. This paper discusses the different methods of surge recovery that have been employed. Data from tests performed at the Cryogenic Test Facility at Fermilab as well as actual Tevatron operational data were utilized. In order to aid in the determination of the surge region, a full mapping study was undertaken to characterize the entire pressure field of the cold compressor. These techniques were then implemented and tested at several locations in the Tevatron with some success.

  10. Searches for Standard Model Higgs at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Cortavitarte, Rocio Vilar; /Cantabria Inst. of Phys.

    2007-11-01

    A summary of the latest results of Standard Model Higgs boson searches from CDF and D0 presented at the DIS 2007 conference is reported in this paper. All analyses presented use 1 fb{sup -1} of Tevatron data. The strategy of the different analyses is determined by the Higgs production mechanism and decay channel.

  11. Searches for New Phenomena at the Tevatron and at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Arnd

    2006-10-01

    Recent results on searches for new physics at Run II of the Tevatron and highlights from HERA are reported. The searches cover many different final states and a wide range of models. All analyses have at this point led to negative results, but some interesting anomalies have been found.

  12. Probing top anomalous couplings at the Tevatron and the Large ...

    Indian Academy of Sciences (India)

    Limits are set on the scale of new physics that might lead to such contributions using latest Tevatron measurements of the t t ¯ cross-section. It is demonstrated that the invariant mass distribution is a sensitive probe. Prospects at the LHC are examined. It is shown that, for unitarized amplitudes, an increase in the LHC energy ...

  13. Weak lensing with GEST

    Science.gov (United States)

    Rhodes, J. D.; Bennett, D. P.; Kaiser, N.

    2001-12-01

    Weak lensing by large-scale structure (cosmic shear) provides an opportunity to directly observe the dark matter in the universe. Current ground-based and space-based surveys have demonstrated the efficacy of this technique in determining the mass distribution and thus placing constraints on cosmological parameters such as Ω m, σ 8, and the bias parameter b. Current surveys have been hampered by the comparatively low resolution of ground-based telescopes and the small field of view of HST. To make significant progress in this field, wide field space-based surveys are needed. The Galactic Exoplanet Survey Telescope (GEST) will be able to provide 500- 1000 sqare degrees with a resolution of better than 0.2 arcseconds in multiple filters. This will make it an ideal instrument for a weak lensing survey.

  14. Tolerancing panoramic lenses

    Science.gov (United States)

    Parent, Jocelyn; Thibault, Simon

    2009-08-01

    Tolerancing a lens is a basic procedure in lens design. It consists in first defining an appropriate set of tolerances for the lens, then in adding compensators with their allowable ranges and finally in selecting an appropriate quality criterion (MTF, RMS spot size, wavefront error, boresight error...) for the given application. The procedure is straightforward for standard optical systems. However, it becomes more complex when tolerancing very wide angle lenses (larger than 150 degrees). With a large field of view, issues such as severe off-axis pupil shift, considerable distortion and low relative illumination must be addressed. The pupil shift affects the raytrace as some rays can no longer be traced properly. For high resolution imagers, particularly for robotic and security applications, the image footprint is most critical in order to limit or avoid complex calibration procedures. We studied various wide angle lenses and concluded that most of the distortion comes from the front surface of the lens. Consequently, any variation of the front surface will greatly affect the image footprint. In this paper, we study the effects on the image footprint of slightly modifying the front surface of four different lenses: a simple double-gauss for comparison, a fisheye lens, a catadioptric system (omnidirectional lens) and a Panomorph lens. We also present a method to analyze variations of the image footprint. Our analysis shows that for wide angle lenses, on which the entrance pupil is much smaller than the front surface, irregularities (amplitude, slope and location) are critical on both aspherical and spherical front surfaces to predict the image footprint variation for high resolution cameras. Finally, we present how the entrance pupil varies (location, size) with the field of view for these optical systems.

  15. Resource Letter GL-1: Gravitational Lensing

    Science.gov (United States)

    Treu, Tommaso; Marshall, Philip J.; Clowe, Douglas

    2012-09-01

    This Resource Letter provides a guide to a selection of the literature on gravitational lensing and its applications. Journal articles, books, popular articles, and websites are cited for the following topics: foundations of gravitational lensing, foundations of cosmology, history of gravitational lensing, strong lensing, weak lensing, and microlensing.

  16. The search for the Higgs at the Tevatron; La recherche du Higgs au Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Lucotte, A

    2004-07-01

    The Tevatron has undergone an impressive technical renovation program whose final aim is to reach an integrated luminosity of 15 fb{sup -1} per experiment. Both CDF and DO detectors have been upgraded in the fields of detection, triggering, track reconstruction and particle identification. In the framework of the standard model, theoretical studies show that for a luminosity of only 2 fb{sup -1} (that is the first step of the renovation program) CDF and DO could barely extend the domain already excluded by LEP for the existence of the Higgs boson. On the other hand for a luminosity of 15 fb{sup -1}, a standard Higgs boson could be excluded up to 180 GeV/c{sup 2} and discovered up to 125 GeV/c{sup 2}. Moreover, a 3*{sigma} result could be obtained in the decay channels H {yields} bb-bar and H {yields} W{sup +}W{sup -} up to 180 GeV/c{sup 2}. In the framework of the minimal supersymmetric standard model (MSSM), at least 20 fb{sup -1} are required for the discovery of the Higgs boson in the energy range: 80 {<=} m{sub A} {<=} 380 GeV/c{sup 2}. (A.C.)

  17. A Study for Doubly-Charged Higgs Boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Baroiant, Sasha [Univ. of California, Davis, CA (United States)

    2006-01-01

    We search for the pair production of doubly charged Higgs particles followed by the lepton-flavor violating decay of each Higgs into electron-and-tau and muonand- tau pairs using 350 pb-1 of data collected by the CDF II experiment at the Fermilab Tevatron. Separate searches investigate cases where three or four finalstate leptons are detected, and the limits for each exclusive decay mode reflect the combined results of both searches. Assuming the H$±±\\atop{L}$ decays exclusively into likesign electron-and-tau pairs, we set a lower limit on its mass of 114 GeV/c2 at the 95 % confidence level. In the case of exclusive muon-and-tau decays, we set a lower mass limit of 112 GeV/c2 also at the 95% confidence level.

  18. A search for double-charged Higgs bosons at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Baraoiant, Sasha [Univ. of California, Davis, CA (United States)

    2006-01-01

    We search for the pair production of doubly charged Higgs particles followed by the lepton-flavor violating decay of each Higgs into electron-and-tau and muon-and-tau pairs using 350 pb-1 of data collected by the CDF II experiment at the Fermilab Tevatron. Separate searches investigate cases where three or four final state leptons are detected, and the limits for each exclusive decay mode reflect the combined results of both searches. Assuming the H$±±\\atop{L}$ decays exclusively into like sign electron-and-tau pairs, we set a lower limit on its mass of 114 GeV/c2 at the 95 % confidence level. In the case of exclusive muon-and-tau decays, we set a lower mass limit of 112 GeV/c2 also at the 95% confidence level.

  19. Cultured human ocular surface epithelium on therapeutic contact lenses.

    Science.gov (United States)

    Di Girolamo, Nick; Chui, Jeanie; Wakefield, Denis; Coroneo, Minas T

    2007-04-01

    This study was initiated after observation of some intriguing epithelial growth properties of contact lenses used as a bandage for patients after pterygium surgery. To determine the efficacy of culturing human ocular surface epithelial cells on therapeutic contact lenses in autologous serum with a view of using this system to transfer epithelial cells to patients with persistent corneal or limbal defects. Excess graft tissue resected from patients undergoing pterygium surgery (n = 3) consisting of limbal epithelium was placed on siloxane-hydrogel contact lenses (lotrafilcon A and balafilcon A). Limbal explants were cultured in media with 10% autologous serum. Morphology, proliferative capacity and cytokeratin profile were determined by phase contrast, light and electron microscopy, and immunohistochemical analysis. Lotrafilcon A contact lenses sustained proliferation and migration from limbal tissue. Cells became confluent after 10-14 days and consisted of 2-3 layers with a corneal phenotype (CK3(+)/CK12(+)/CK19(-)) and a propensity to proliferate (p63(+)). Electron microscopy showed microvilli on the apical surface with adhesive projections, indicating that these cells were stable and likely to survive for a long term. Growth was not observed from limbal explants cultured on balafilcon A contact lenses. A method for culturing human ocular surface epithelium on contact lenses that may facilitate expansion and transfer of autologous limbal epithelial cells while avoiding the risks associated with transplanting allogeneic tissue has been developed. This technique may be potentially useful for the treatment of patients with limbal stem cell deficiency.

  20. Transparent nanostructured photochromic UV-blocking soft contact lenses.

    Science.gov (United States)

    Pek, Y Shona; Wu, Hong; Chow, Edwin Py; Ying, Jackie Y

    2016-06-01

    We aim to develop transparent UV-blocking photochromic soft contact lenses via polymerization of a bicontinuous nanoemulsion. Transparent nanostructured polymers were prepared by incorporating a polymerizable surfactant and thermal initiator together with water, monomers, UV blockers and photochromic dyes. The polymers were characterized using oxygen permeometer, tensile tester, electron microscope, UV spectrophotometer, corneal cell culture and testing in rabbits. The polymers have good oxygen permeability, water content, stiffness, strength and UV-blocking ability comparable to commercial UV-blocking soft contact lenses. Their response to UV light is comparable to photochromic spectacle lenses, particularly in reverse transition from colored to colorless state. They are nontoxic and nonleaching. Our photochromic UV-blocking contact lenses provide a novel alternative to photochromic spectacles.

  1. Additive manufacturing of tunable lenses

    Science.gov (United States)

    Schlichting, Katja; Novak, Tobias; Heinrich, Andreas

    2017-02-01

    Individual additive manufacturing of optical systems based on 3D Printing offers varied possibilities in design and usage. In addition to the additive manufacturing procedure, the usage of tunable lenses allows further advantages for intelligent optical systems. Our goal is to bring the advantages of additive manufacturing together with the huge potential of tunable lenses. We produced tunable lenses as a bundle without any further processing steps, like polishing. The lenses were designed and directly printed with a 3D Printer as a package. The design contains the membrane as an optical part as well as the mechanical parts of the lens, like the attachments for the sleeves which contain the oil. The dynamic optical lenses were filled with an oil. The focal length of the lenses changes due to a change of the radius of curvature. This change is caused by changing the pressure in the inside of the lens. In addition to that, we designed lenses with special structures to obtain different areas with an individual optical power. We want to discuss the huge potential of this technology for several applications. Further, an appropriate controlling system is needed. Wéll show the possibilities to control and regulate the optical power of the lenses. The lenses could be used for illumination tasks, and in the future, for individual measurement tasks. The main advantage is the individuality and the possibility to create an individual design which completely fulfills the requirements for any specific application.

  2. The Tevatron tune tracker pll - theory, implementation and measurements

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Cheng-Yang; /Fermilab

    2004-12-01

    The Tevatron tune tracker is based on the idea that the transverse phase response of the beam can be measured quickly and accurately enough to allow us to track the betatron tune with a phase locked loop (PLL). The goal of this paper is to show the progress of the PLL project at Fermilab. We will divide this paper into three parts: theory, implementation and measurements. In the theory section, we will use a simple linear model to show that our design will track the betatron tune under conditions that occur in the Tevatron. In the implementation section we will break down and examine each part of the PLL and in some cases calculate the actual PLL parameters used in our system from beam measurements. And finally in the measurements section we will show the results of the PLL performance.

  3. Review of Physics Results from the Tevatron: Top Quark Physics

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, Cecilia E.; Vellidis, Costas

    2014-09-17

    We present results on top quark physics from the CDF and D0 collaborations at the Fermilab Tevatron proton anti-proton collider. These include legacy results from Run II that were published or submitted for publication before mid-2014, as well as a summary of Run I results. The historical perspective of the discovery of the top quark in Run I is also described.

  4. Top quark pair production cross section at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Cortiana, Giorgio; /INFN, Padua /Padua U.

    2008-04-01

    Top quark pair production cross section has been measured at the Tevatron by CDF and D0 collaborations using different channels and methods, in order to test standard model predictions, and to search for new physics hints affecting the t{bar t} production mechanism or decay. Measurements are carried out with an integrated luminosity of 1.0 to 2.0 fb{sup -1}, and are found to be consistent with standard model expectations.

  5. Top Quark Production Cross Section at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shabalina, E.; /Chicago U.

    2006-05-01

    An overview of the preliminary results of the top quark pair production cross section measurements at a center-of-mass energy of 1.96 TeV carried out by the CDF and D0 collaborations is presented. The data samples used for the analyses are collected in the current Tevatron run and correspond to an integrated luminosity from 360 pb{sup -1} up to 760 pb{sup -1}.

  6. Selected Topics from Top Mass Measurements at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Schwienhorst, Reinhard [Michigan State U.

    2016-12-07

    The most recent results of the top-quark mass measurements at the Tevatron at Fermilab are presented. Data were collected in proton-antiproton collisions at sqrt{s}=1.96 TeV by the CDF and D0 experiments. Top quark mass measurements in the lepton+jets, dilepton and alljet final states as well as their combination and the extraction of the mass from the cross-section measurement are presented.

  7. Search for supersymmetric neutral Higgs bosons at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Scanlon, Tim; /Imperial Coll., London

    2007-10-01

    Recent preliminary results obtained by the CDF and D0 Collaborations on searches for Higgs bosons beyond the Standard Model at Run II of the Tevatron are discussed. The data, corresponding to integrated luminosities of up to 1 fb{sup -1}, are compared to theoretical expectations. No significant excess of signal above the expected background is observed in any of the various final states examined, and so limits at 95% Confidence Level (CL) are presented.

  8. Tevatron-for-LHC Report: Preparations for Discoveries

    Energy Technology Data Exchange (ETDEWEB)

    Buescher, V.; Carena, Marcela S.; Dobrescu, Bogdan A.; Mrenna, S.; Rainwater, D.; Schmitt, M.

    2006-08-01

    This is the ''TeV4LHC'' report of the ''Physics Landscapes'' Working Group, focused on facilitating the start-up of physics explorations at the LHC by using the experience gained at the Tevatron. We present experimental and theoretical results that can be employed to probe various scenarios for physics beyond the Standard Model.

  9. Exclusive Photoproduction of ϒ:. from Hera to Tevatron

    Science.gov (United States)

    Rybarska, Anna; Schäfer, Wolfgang; Szczurek, Antoni

    The amplitude for photoproduction γp → ϒp is calculated in a pQCD k⊥-factorization approach. The total cross section for diffractive ϒs is compared to recent HERA data. The amplitude is used to predict the cross section for exclusive pbar p-> pΥ (1S, 2S)bar p proces in hadronic reactions at Tevatron energies. We also included absorption effects.

  10. Review of charged Higgs searches at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, Phillip; /Oklahoma U.

    2010-12-01

    Although the standard model of particle physics (SM) is remarkably successful at describing the fundamental particles and their interactions, the mechanism for the breaking of elecroweak symmetry (EWSB) has yet to be confirmed. In the SM, the EWSB sector consists of four scalar fields represented by a single SU(2) complex doublet. Following EWSB, three of the fields are responsible for the generation of the W{sup {+-}} and Z masses, while the fourth is the neutral Higgs boson. At the present time, the Tevatron experiments have set 95% CL exclusion limits on the mass of the SM Higgs boson for the ranges 100 to 109 GeV and 158 to 175 GeV. In addition to these constraints on the SM Higgs boson, the Tevatron experiments have also set limits on neutral and charged Higgs bosons (H{sup {+-}}) in the context of several models beyond the SM. In this review, we discuss searches for charged Higgs bosons performed by the CDF and D0 collaborations at the Fermilab Tevatron in the mass range of 80 to 300 GeV.

  11. Pressure field study of the Tevatron cold compressors

    Energy Technology Data Exchange (ETDEWEB)

    Klebaner, A.L.; Martinez, A.; Soyars, W.M.; Theilacker, J.C.; /Fermilab

    2003-01-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations [1]. The compressor is designed to pump 60 g/sec of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/sec. Operating speeds are between 40 and 95 krpm, with a speed of 80 krpm at the design point. Different heat loads and magnet quench performance of each of the twenty-four satellite refrigerators dictates different process pressure and flow rates of the cold compressors. Reducing the process flow rate can cause the centrifugal cold compressor to stop pumping and subsequently surge. Tests have been conducted at the Cryogenic Test Facility at Fermilab to map the pressure field and appropriate efficiency of the IHI hydrodynamic cold compressor. The information allows tuning of each of the twenty-four Tevatron satellite refrigerators to avoid cold compressor operation near the surge and choke lines. A new impeller has also been tested. The Tevatron cold compressor pressure field and efficiency data with the new impeller are presented in this paper.

  12. Pressure Field Study of the Tevatron Cold Compressors

    Science.gov (United States)

    Klebaner, A. L.; Martinez, A.; Soyars, W. M.; Theilacker, J. C.

    2004-06-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations. The compressor is designed to pump 60 g/sec of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/sec. Operating speeds are between 40,000 and 95,000 rpm, with a speed of 80,000 rpm at the design point. Different heat loads and magnet quench performance of each of the twenty-four satellite refrigerators dictates different process pressure and flow rates of the cold compressors. Reducing the process flow rate can cause the centrifugal cold compressor to stop pumping and subsequently surge. Tests have been conducted at the Cryogenic Test Facility at Fermilab to map the pressure field and appropriate efficiency of the IHI hydrodynamic cold compressor. The information allows tuning of each of the twenty-four Tevatron satellite refrigerators to avoid cold compressor operation near the surge and choke lines. A new impeller has also been tested. The Tevatron cold compressor pressure field and efficiency data with the new impeller are presented in this paper.

  13. Next-to-Leading Order {QCD} Predictions for $Z, \\gamma^*$ + 3-Jet Distributions at the Tevatron

    CERN Document Server

    Berger, C.F.; Dixon, Lance J.; Febres Cordero, F.; Forde, D.; Gleisberg, T.; Ita, H.; Kosower, D.A.; Maitre, D.

    2010-01-01

    Using BlackHat in conjunction with SHERPA, we have computed next-to-leading order QCD predictions for a variety of distributions in Z,gamma*+1,2,3-jet production at the Tevatron, where the Z boson or off-shell photon decays into an electron-positron pair. We find good agreement between the NLO results for jet p_T distributions and measurements by CDF and D0. We also present jet-production ratios, or probabilities of finding one additional jet. As a function of vector-boson p_T, the ratios have distinctive features which we describe in terms of a simple model capturing leading logarithms and phase-space and parton-distribution-function suppression.

  14. Subaru Weak Lensing Measurements of Four Strong Lensing Clusters: Are Lensing Clusters Over-Concentrated?

    Energy Technology Data Exchange (ETDEWEB)

    Oguri, Masamune; Hennawi, Joseph F.; Gladders, Michael D.; Dahle, Haakon; Natarajan, Priyamvada; Dalal, Neal; Koester, Benjamin P.; Sharon, Keren; Bayliss, Matthew

    2009-01-29

    We derive radial mass profiles of four strong lensing selected clusters which show prominent giant arcs (Abell 1703, SDSS J1446+3032, SDSS J1531+3414, and SDSS J2111-0115), by combining detailed strong lens modeling with weak lensing shear measured from deep Subaru Suprime-cam images. Weak lensing signals are detected at high significance for all four clusters, whose redshifts range from z = 0.28 to 0.64. We demonstrate that adding strong lensing information with known arc redshifts significantly improves constraints on the mass density profile, compared to those obtained from weak lensing alone. While the mass profiles are well fitted by the universal form predicted in N-body simulations of the {Lambda}-dominated cold dark matter model, all four clusters appear to be slightly more centrally concentrated (the concentration parameters c{sub vir} {approx} 8) than theoretical predictions, even after accounting for the bias toward higher concentrations inherent in lensing selected samples. Our results are consistent with previous studies which similarly detected a concentration excess, and increases the total number of clusters studied with the combined strong and weak lensing technique to ten. Combining our sample with previous work, we find that clusters with larger Einstein radii are more anomalously concentrated. We also present a detailed model of the lensing cluster Abell 1703 with constraints from multiple image families, and find the dark matter inner density profile to be cuspy with the slope consistent with -1, in agreement with expectations.

  15. Pulsar lensing geometry

    Science.gov (United States)

    Liu, Siqi; Pen, Ue-Li; Macquart, J.-P.; Brisken, Walter; Deller, Adam

    2016-05-01

    We test the inclined sheet pulsar scintillation model (Pen & Levin) against archival very long baseline interferometry (VLBI) data on PSR 0834+06 and show that its scintillation properties can be precisely reproduced by a model in which refraction occurs on two distinct lens planes. These data strongly favour a model in which grazing-incidence refraction instead of diffraction off turbulent structures is the primary source of pulsar scattering. This model can reproduce the parameters of the observed diffractive scintillation with an accuracy at the percent level. Comparison with new VLBI proper motion results in a direct measure of the ionized interstellar medium (ISM) screen transverse velocity. The results are consistent with ISM velocities local to the PSR 0834+06 sight-line (through the Galaxy). The simple 1-D structure of the lenses opens up the possibility of using interstellar lenses as precision probes for pulsar lens mapping, precision transverse motions in the ISM, and new opportunities for removing scattering to improve pulsar timing. We describe the parameters and observables of this double screen system. While relative screen distances can in principle be accurately determined, a global conformal distance degeneracy exists that allows a rescaling of the absolute distance scale. For PSR B0834+06, we present VLBI astrometry results that provide (for the first time) a direct measurement of the distance of the pulsar. For most of the recycled millisecond pulsars that are the targets of precision timing observations, the targets where independent distance measurements are not available. The degeneracy presented in the lens modelling could be broken if the pulsar resides in a binary system.

  16. Supernova forecast with strong lensing

    Science.gov (United States)

    Suwa, Yudai

    2018-02-01

    In the coming Large Synoptic Survey Telescope era, we will observe O(100) of lensed supernovae (SNe). In this paper, we investigate the possibility for predicting time and sky position of an SN using strong lensing. We find that it will be possible to predict the time and position of the fourth image of SNe which produce four images by strong lensing, with combined information from the three previous images. It is useful to perform multimessenger observations of the very early phase of SN explosions including the shock breakout.

  17. Bacterial adherence to extended wear soft contact lenses

    Energy Technology Data Exchange (ETDEWEB)

    Aswad, M.I.; John, T.; Barza, M.; Kenyon, K.; Baum, J. (New England Medical Center, Boston, MA (USA))

    1990-03-01

    The authors studied the adherence of Pseudomonas aeruginosa and Staphylococcus aureus to extended wear soft contact lenses (EWSCLs) with and without focal deposits using both a radiolabeling technique and electron microscopy. P. aeruginosa showed significant adherence to contact lenses in vitro. In contrast, S. aureus failed to show significant adherence to contact lenses in vitro (i.e., the radioactive uptake was not significantly above background). The extent of adherence of Pseudomonas was proportional to the number of focal deposits on the lenses. Results of electron microscopic examination showed the bacteria to be adherent primarily to large focal deposits (greater than or equal to 150 microns). There was no pseudomonal adherence to the small focal deposits (less than or equal to 50 microns) and little adherence to the areas in between the focal deposits. The authors hypothesize that worn lenses, especially those with large focal deposits, serve as a vehicle for the transport of P. aeruginosa to the cornea. This hypothesis could be a partial explanation for the high incidence of keratitis caused by P. aeruginosa in EWSCL patients.

  18. Planar Lenses at Visible Wavelengths

    CERN Document Server

    Khorasaninejad, Mohammadreza; Devlin, Robert C; Oh, Jaewon; Zhu, Alexander Y; Capasso, Federico

    2016-01-01

    Sub-wavelength resolution imaging requires high numerical aperture (NA) lenses, which are bulky and expensive. Metasurfaces allow the miniaturization of conventional refractive optics into planar structures. We show that high-aspect-ratio titanium dioxide metasurfaces can be fabricated and designed as meta-lenses with NA = 0.8. Diffraction-limited focusing is demonstrated at wavelengths of 405 nm, 532 nm, and 660 nm with corresponding efficiencies of 86%, 73%, and 66%. The meta-lenses can resolve nanoscale features separated by sub-wavelength distances and provide magnification as high as 170x with image qualities comparable to a state-of-the-art commercial objective. Our results firmly establish that meta-lenses can have widespread applications in laser-based microscopy, imaging, and spectroscopy.

  19. KINOFORM LENSES - TOWARD NANOMETER RESOLUTION.

    Energy Technology Data Exchange (ETDEWEB)

    STEIN, A.; EVANS-LUTTERODT, K.; TAYLOR, A.

    2004-10-23

    While hard x-rays have wavelengths in the nanometer and sub-nanometer range, the ability to focus them is limited by the quality of sources and optics, and not by the wavelength. A few options, including reflective (mirrors), diffractive (zone plates) and refractive (CRL's) are available, each with their own limitations. Here we present our work with kinoform lenses which are refractive lenses with all material causing redundant 2{pi} phase shifts removed to reduce the absorption problems inherently limiting the resolution of refractive lenses. By stacking kinoform lenses together, the effective numerical aperture, and thus the focusing resolution, can be increased. The present status of kinoform lens fabrication and testing at Brookhaven is presented as well as future plans toward achieving nanometer resolution.

  20. Measurements of top quark production and properties at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Bartos, P. [Comenius U.

    2014-09-15

    In this letter, we summarize the latest results of the top-quark production and properties at the Tevatron. We do not include results of the top-quark mass and single top-quark production as they were presented in separate talks. The results of the measurements are mostly consistent with the standard-model predictions. However, by looking at the production asymmetry measured by CDF, one can see a discrepancy in both, $t\\bar{t}$ inclusive and lepton-based measurements. D\\O\\ results of production asymmetry are compatible with the standard-model predictions as well as with the CDF results.

  1. Top Production at the Tevatron: The Antiproton Awakens

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, Kenneth [Nebraska U.

    2017-07-01

    A long time ago, at a laboratory far, far away, the Fermilab Tevatron collided protons and antiprotons at $\\sqrt{s} = 1.96$ TeV. The CDF and D0 experiments each recorded datasets of about 10 fb$^{-1}$. As such experiments may never be repeated, these are unique datasets that allow for unique measurements. This presentation describes recent results from the two experiments on top-quark production rates, spin orientations, and production asymmetries, which are all probes of the $p\\bar{p}$ initial state.

  2. Electroweak and B physics results from the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, K.T.

    2001-01-30

    This writeup is an introduction to some of the experimental issues involved in performing electroweak and b physics measurements at the Fermilab Tevatron. In the electroweak sector, we discuss W and Z boson cross section measurements as well as the measurement of the mass of the W boson. For b physics, we discuss measurements of B{sup 0}/{bar B}{sup 0} mixing and CP violation. This paper is geared towards nonexperts who are interested in understanding some of the issues and motivations for these measurements and how the measurements are carried out.

  3. Studies of top quark properties at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shary, Viatcheslav

    2012-05-01

    An overview of the recent measurements of the top quark properties in proton antiproton collisions at {radical}s = 1.96 TeV is presented. These measurements are based on 5.4-8.7 fb{sup -1} of data collected with the D0 and CDF experiments at the Fermilab Tevatron collider. The top quark mass and width measurements, studies of the spin correlation in top quark pair production, W boson helicity measurement, searches for anomalous top quark couplings and Lorentz invariance violation are discussed.

  4. $B$ physics at the Tevatron: Run II and beyond

    CERN Document Server

    Anikeev, K; Azfar, F.; Bailey, S.; Bauer, C.W.; Bell, W.; Bodwin, G.; Braaten, E.; Burdman, G.; Butler, J.N.; Byrum, K.; Cason, N.; Cerri, A.; Cheung, H.W.K.; Dighe, A.; Donati, S.; Ellis, R.K.; Falk, A.; Feild, G.; Fleming, S.; Furic, I.; Gardner, S.; Grossman, Y.; Gutierrez, G.; Hao, W; Harris, B.W.; Hewett, J.; Hiller, G.; Jesik, R.; Jones, M.; Kasper, P.A.; El-Khadra, A.; Kirk, M.; Kiselev, V.V.; Kroll, J.; Kronfeld, A.S.; Kutschke, R.; Kuznetsov, V.E.; Laenen, E.; Lee, J.; Leibovich, A.K.; Lewis, J.D.; Ligeti, Z.; Likhoded, A.K.; Logan, H.E.; Luke, M.; Maciel, A.; Majumder, G.; Maksimovic, P.; Martin, M.; Menary, S.; Nason, P.; Nierste, U.; Nir, Y.; Nogach, L.; Norrbin, E.; Oleari, C.; Papadimitriou, V.; Paulini, M.; Paus, C.; Petteni, M.; Poling, R.; Procario, M.; Punzi, G.; Quinn, H.; Rakitine, A.; Ridolfi, G.; Shestermanov, K.; Signorelli, G.; Silva, J.P.; Skwarnicki, T.; Smith, A.; Speakman, B.; Stenson, K.; Stichelbaut, F.; Stone, S.; Sumorok, K.; Tanaka, M.; Taylor, W.; Trischuk, W.; Tseng, J.; Van Kooten, R.; Vasiliev, A.; Voloshin, M.; Wang, J.C.; Wicklund, A.B.; Wurthwein, F.; Xuan, N.; Yarba, J.; Yip, K.; Zieminski, A.

    2002-01-01

    This report provides a comprehensive overview of the prospects for B physics at the Tevatron. The work was carried out during a series of workshops starting in September 1999. There were four working groups: 1) CP Violation, 2) Rare and Semileptonic Decays, 3) Mixing and Lifetimes, 4) Production, Fragmentation and Spectroscopy. The report also includes introductory chapters on theoretical and experimental tools emphasizing aspects of B physics specific to hadron colliders, as well as overviews of the CDF, D0, and BTeV detectors, and a Summary.

  5. Top quark production and properties at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Frank; /Munich U.

    2005-06-01

    The precise measurement of top quark production and properties is one of the primary goals of the Tevatron during Run II. The total t{bar t} production cross-section has been measured in a large variety of decay channels and using different selection criteria. Results from differential cross-section measurements and searches for new physics in t{bar t} production and top quark decays are available. Electroweak production of single top quarks has been searched for. The results from all these analyses, using typically 200 pb{sup -1} of data, are presented.

  6. Review of physics results from the Tevatron: QCD physics

    Energy Technology Data Exchange (ETDEWEB)

    Mesropian, Christina [Rockefeller U.; Bandurin, Dmitry [Virginia U.

    2015-02-17

    We present a summary of results from studies of quantum chromodynamics at the Fermilab Tevatron collider by the CDF and the D0 experiments. These include Run II results for the time period up to the end of Summer 2014. A brief description of Run I results is also given. This review covers a wide spectrum of topics, and includes measurements with jet and vector boson final states in the hard (perturbative) energy regime, as well as studies of soft physics such as diffractive and elastic scatterings, underlying and minimum bias events, hadron fragmentation, and multiple parton interactions.

  7. SUSY + Beyond Standard Model Higgs Searches at the Tevatron

    Directory of Open Access Journals (Sweden)

    Abid Patwa

    2012-06-01

    Full Text Available Recent results by the CDF and DØ Collaborations for non-Standard Model Higgs boson searches in pp¯ $par p$ collisions at center-of-mass energy of √s = 1.96 TeV using up to 8.2 fb−1 of Fermilab Tevatron data are discussed. Searches for neutral Higgs bosons predicted in the Minimal Supersymmetric Standard Model (MSSM, doubly-charged Higgs bosons predicted in extended models, as well as Higgs bosons within Hidden Valley and Fermiophobic models are described.

  8. Spectroscopy and Decay of $B$ Hadrons at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Paulini, Manfred

    2007-02-01

    The authors review recent results on heavy quark physics focusing on Run II measurements of B hadron spectroscopy and decay at the Tevatron. A wealth of new B physics measurements from CDF and D0 has been available. These include the spectroscopy of excited B states (B**, B**{sub s}) and the observation of the {Sigma}{sub b} baryon. The discussion of the decays of B hadrons and measurements of branching fractions focuses on charmless two-body decays of B {yields} h{sup +}h{sup -}. They report several new B{sub s}{sup 0} and {Lambda}{sub b}{sup 0} decay channels.

  9. B Lambda_b and Charm Results from the Tevatron

    CERN Document Server

    Azfar, F

    2003-01-01

    Recent results on $B_d$, $B_u^{\\pm}$, $B_s$, $\\Lambda_b$ and Charm hadrons are reported from $\\approx$ 75pb$^{-1}$ and $\\approx$ 40 pb$^{-1}$ of data accumulated at the upgraded CDF and D0 experiments at the Fermilab Tevatron $\\bar{p}-p$ collider, during Run-II. These include lifetime and mass measurements of $B$ and Charm hadrons, searches for rare decays in charm and $B$ hadrons and CP-violation in Charm decays. Results relevant to CP-violation in B-decays are also reported.

  10. B0(s) mixing studies at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Naimuddin, M.D.; /Delhi U.

    2006-05-01

    Measurement of the B{sub s}{sup 0} oscillation frequency via B{sub s}{sup 0} mixing analysis provides a powerful constraint on CKM matrix elements. This note briefly reviews the motivation behind these analyses and describes the various steps that go into a mixing measurement. Recent results on B{sub s}{sup 0} mixing obtained by the CDF and D0 collaborations using the data samples collected at Tevatron Collider in the period 2002-2005 are presented.

  11. High Mass Standard Model Higgs searches at the Tevatron

    Directory of Open Access Journals (Sweden)

    Petridis Konstantinos A.

    2012-06-01

    Full Text Available We present the results of searches for the Standard Model Higgs boson decaying predominantly to W+W− pairs, at a center-of-mass energy of √s = 1.96 TeV, using up to 8.2 fb−1 of data collected with the CDF and D0 detectors at the Fermilab Tevatron collider. The analysis techniques and the various channels considered are discussed. These searches result in exclusions across the Higgs mass range of 156.5< mH <173.7 GeV for CDF and 161< mH <170 GeV for D0.

  12. Studies of single top quark production at the Tevatron

    CERN Document Server

    Quinn, Breese

    2011-01-01

    In this paper we present several measurements of single top quark production from the CDF and D0 experiments at the Tevatron. The various analyses utilize integrated luminosity ranging from 2.1 to 4.8 fb -1. The results include the observation of single top production with a combined cross section of 2.76 +0.58 -0.47 pb for a top quark mass of 170 GeV/c2, as well as measurements of top quark polarization and first evidence for t-channel production.

  13. Resonant second generation slepton production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Autermann, Christian Tobias [RWTH Aachen Univ. (Germany)

    2006-12-01

    A search for R-parity violating supersymmetry with the D0 detector at the Fermilab Tevatron p$\\bar{p}$-collider is presented. Assuming a non-zero LQ$\\bar{d}$ coupling λ$'\\atop{2jk}$ leads to final state with two muons and jets. A total integrated luminosity of 375 pb-1 collected between April 2002 and August 2004 is utilized. The observed number of events is in agreement with the Standard Model expectation, and limits on Rp supersymmetry are derived.

  14. Record-breaking luminosity boosts discovery potential at Fermilab's Tevatron collider

    CERN Multimedia

    Fermi National Accelerator Laboratory. Batavia

    2006-01-01

    The record-breaking performance of the Tevatron colklider at the Department of Energy's Fermi National Accelerator Laboratory is pushing tje search fpr dark matter, supersymmetric particles and extra dimensions to new limits. Repeatedly smashing peak luminosity records, the Tevatron has created record numbers of proton-antiproton collisions that provide the means to unveil the secrets of the universe

  15. Review of Heavy Flavor Physics at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Giurgiu, Gavril; /Johns Hopkins U.

    2011-10-01

    The D0 and CDF detectors at the Fermilab Tevatron have each accumulated more that 9 fb{sup -1} of integrated luminosity. The corresponding large datasets enable the two experiments to perform unprecedented studies of heavy flavor hadron properties. We present recent D0 and CDF measurements, focusing on rare decays and CP violation in B-meson decays. Flavor Physics probes new phenomena by either searching for small deviations from the Standard Model (SM) based theoretical predictions or by measuring quantities which are highly suppressed within the SM. Searching for small deviations from the SM are performed using large strange, charm or bottom hadron samples, mostly by kaon experiments of B factories. Measurements of highly suppressed quantities, such as CP violation phases and asymmetries in the neutral B{sub s}-meson system or searches for rare B decays, are performed with the hope that new physics effects would be large enough to significantly affect the measured quantities and so, lead to observations of deviations from the SM expectations. The D0 and CDF detectors at the Fermilab Tevatron have each accumulated more that 9 fb{sup -1} of integrated luminosity. The corresponding large datasets enable the two experiments to perform unprecedented studies of heavy flavor hadron properties. We present recent D0 and CDF measurements, focusing on rare decays and CP violation in B-meson decays.

  16. In celebration of the fixed target program with the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey A. Appel et al.

    2001-12-28

    The Tevatron is the world's first large superconducting accelerator. With its construction, we gained the dual opportunities to advance the state of the art in accelerator technology with the machine itself and in particle physics with the experiments that became possible in a higher energy regime. There have been 43 experiments in the Tevatron fixed target program. Many of these are better described as experimental programs, each with a broad range of physics goals and results, and more than 100 collaborating physicists and engineers. The results of this program are three-fold: (1) new technologies in accelerators, beams and detectors which advanced the state of the art; (2) new experimental results published in the refereed physics journals; and (3) newly trained scientists who are both the next generation of particle physicists and an important part of the scientific, technical and educational backbone of the country as a whole. In this book they compile these results. There are sections from each experiment including what their physics goals and results were, what papers were published, and which students have received degrees. Summaries of these results from the program as a whole are quite interesting, but the physics results from this program are too broad to summarize globally. The most important of the results appear in later sections of this booklet.

  17. Evaluation of pigment location in tinted soft contact lenses.

    Science.gov (United States)

    Jung, Ji Won; Han, Sun Hyup; Kim, Sang Ah; Kim, Eung Kweon; Seo, Kyoung Yul; Kim, Tae-Im

    2016-06-01

    The purpose of this study was to investigate efficient methods to evaluate the pigment layer location of tinted soft contact lenses and to assess various lens products on the market using those methods. Two types of tinted soft contact lenses with known pigment location embedded or back surface were manufactured and examined. Light microscopy (LM), focused ion beam milling and scanning electron microscopy (FIB-SEM), and Fourier-domain optical coherence tomography (FD-OCT) were used to examine the pigment layer. Lens surface roughness was also measured using atomic force microscopy. In the second part of the experiment, pigment location and surface roughness of a clear lens (Lens A) and eight commercially-available tinted soft contact lenses (Lens B-I) were evaluated using FIB-SEM and FD-OCT. Pigment location could be reliably determined with FIB-SEM and FD-OCT. With LM, 40% of the lens sections were broken or deformed during slide preparation. The pigment particles in Lens B were buried below the front surface and there were no significant differences of roughness between the front and back surfaces. However, all tinted lenses with surface pigment had significant difference of roughness between front and back surfaces at the pigmented area. The FIB-SEM and FD-OCT could reliably locate the pigment layer of tinted soft contact lenses. In addition, lens surface roughness was influenced by pigment layer location. Copyright © 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  18. Experimental and Numerical Studies on the Proposed Application of Hollow Electron Beam Collimation for the LHC at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Moens, Vince [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-01-01

    This thesis work was carried out in the framework of the U.S. LHC Accelerator Research Program (USLARP), a collaboration between the European Organization for Nuclear Research (CERN) and the U.S. Department of Energy. The first half of the work was completed at Fermilab (USA), the location of the Tevatron, a proton-antiproton collider and the second largest particle collider in the world. The second half was completed at CERN (Switzerland), the location of the largest proton collider in the world (Large Hadron Collider (LHC)). This thesis characterizes a Hollow Electron Beam (HEB) for possible usage at the LHC to enhance its collimation through Hollow Electron Beam Lenses (HEBLs). Collimation is a long established principle in high energy particle accelerators. Hollow Electron Beam Collimation (HEBC) aims to enhance current collimation systems by controlling diffusion of primary halo particles into the limiting aperture. It works on the principle of a transverse radial electric field that kicks the primary halo particles outwards upon each pass in a multi-pass system. The transverse field is produced by a HEB that is coaxially aligned with the accelerator beam, producing a negligible electric field in the center and a strong transverse electric field at amplitudes higher than the inner radius of the electron beam. Ideally, halo particles are affected without perturbation of the beam core. One of the main advantages of this system is to decrease the dependence on instantaneous loss spikes and beam jitter. A solid experimental basis of HEBC was accumulated at the Tevatron. The application of this technique at the LHC is now under investigation. The aim of this thesis is to present a preliminary report to support a future optimal conceptual design report. It characterizes the available hardware in order to facilitate the design of a Hollow Electron Gun (HEG) for the LHC, characterizes the effect on beam diffusion by determining the transverse electric fields of the

  19. Thermal lensing in ocular media

    Science.gov (United States)

    Vincelette, Rebecca Lee

    2009-12-01

    This research was a collaborative effort between the Air Force Research Laboratory (AFRL) and the University of Texas to examine the laser-tissue interaction of thermal lensing induced by continuous-wave, CW, near-infrared, NIR, laser radiation in the eye and its influence on the formation of a retinal lesion from said radiation. CW NIR laser radiation can lead to a thermal lesion induced on the retina given sufficient power and exposure duration as related to three basic parameters; the percent of transmitted energy to, the optical absorption of, and the size of the laser-beam created at the retina. Thermal lensing is a well-known phenomenon arising from the optical absorption, and subsequent temperature rise, along the path of the propagating beam through a medium. Thermal lensing causes the laser-beam profile delivered to the retina to be time dependent. Analysis of a dual-beam, multidimensional, high-frame rate, confocal imaging system in an artificial eye determined the rate of thermal lensing in aqueous media exposed to 1110, 1130, 1150 and 1318-nm wavelengths was related to the power density created along the optical axis and linear absorption coefficient of the medium. An adaptive optics imaging system was used to record the aberrations induced by the thermal lens at the retina in an artificial eye during steady-state. Though the laser-beam profiles changed over the exposure time, the CW NIR retinal damage thresholds between 1110--1319-nm were determined to follow conventional fitting algorithms which neglected thermal lensing. A first-order mathematical model of thermal lensing was developed by conjoining an ABCD beam propagation method, Beer's law of attenuation, and a solution to the heat-equation with respect to radial diffusion. The model predicted that thermal lensing would be strongest for small (retina. The model predicted thermal lensing would cause the retinal damage threshold for wavelengths above 1300-nm to increase with decreasing beam

  20. Use of Scleral Lenses and Miniscleral Lenses After Penetrating Keratoplasty.

    Science.gov (United States)

    Barnett, Melissa; Lien, Vivian; Li, Jennifer Y; Durbin-Johnson, Blythe; Mannis, Mark J

    2016-05-01

    To examine the clinical outcomes of scleral lenses for visual rehabilitation after penetrating keratoplasty (PK). A retrospective review was conducted for 34 patients (48 eyes) who had a history of prior PK and were fit with scleral lenses between October 2009 and December 2013 at the UC Davis Eye Center. The most common initial indication for PK was keratoconus in 27 eyes (56%). Thirty-three eyes (69%) had previously been fit with other types of contact lenses, with small-diameter rigid gas-permeable lenses being the most common. The improvement in best-corrected visual acuity with a scleral lens compared with prior spectacle refraction or other contact lens was a mean of two best-corrected visual acuity lines. Forty-four eyes (91.7%) achieved functional vision with best scleral lens-corrected visual acuities of 20/40 or better. Patients who continued wearing scleral lenses were significantly more likely to report "good" subjective vision compared with patients who abandoned scleral lens wear (P=0.009), although change in objective best-corrected visual acuity did not differ significantly. There were no cases of infectious keratitis. Six eyes (12.5%) developed graft rejection; 3 were able to resume scleral lens wear. Nineteen eyes (39.5%) discontinued scleral lens wear for various reasons, the most common reason for discontinuation of lens wear was difficulty with scleral lens insertion or removal (8 eyes, 42.1%). Scleral lenses are effective and safe in patients who have had PK. There was a mean gain in visual acuity, with the majority of patients achieving 20/40 vision or better. The patient's subjective perception of vision was a significant factor in determining whether scleral lens wear was continued or abandoned.

  1. Surface gravity-wave lensing

    Science.gov (United States)

    Elandt, Ryan B.; Shakeri, Mostafa; Alam, Mohammad-Reza

    2014-02-01

    Here we show that a nonlinear resonance between oceanic surface waves caused by small seabed features (the so-called Bragg resonance) can be utilized to create the equivalent of lenses and curved mirrors for surface gravity waves. Such gravity wave lenses, which are merely small changes to the seafloor topography and therefore are surface noninvasive, can focus or defocus the energy of incident waves toward or away from any desired focal point. We further show that for a broadband incident wave spectrum (i.e., a wave group composed of a multitude of different-frequency waves), a polychromatic topography (occupying no more than the area required for a monochromatic lens) can achieve a broadband lensing effect. Gravity wave lenses can be utilized to create localized high-energy wave zones (e.g., for wave energy harvesting or creating artificial surf zones) as well as to disperse waves in order to create protected areas (e.g., harbors or areas near important offshore facilities). In reverse, lensing of oceanic waves may be caused by natural seabed features and may explain the frequent appearance of very high amplitude waves in certain bodies of water.

  2. The M31 pixel lensing plan campaign: MACHO lensing and self-lensing signals

    Energy Technology Data Exchange (ETDEWEB)

    Calchi Novati, S.; Scarpetta, G. [Istituto Internazionale per gli Alti Studi Scientifici (IIASS), Via Pellegrino 19, I-84019 Vietri Sul Mare (Italy); Bozza, V. [Dipartimento di Fisica E. R. Caianiello, Università di Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano (Italy); Bruni, I.; Gualandi, R. [INAF, Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Dall' Ora, M. [INAF, Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); De Paolis, F.; Ingrosso, G.; Nucita, A.; Strafella, F. [Dipartimento di Matematica e Fisica E. De Giorgi, Università del Salento, CP 193, I-73100 Lecce (Italy); Dominik, M. [SUPA, University of St Andrews, School of Physics and Astronomy, North Haugh, St Andrews, KY16 9SS (United Kingdom); Jetzer, Ph. [Institute for Theoretical Physics, University of Zürich, Winterthurerstrasse 190, 8057 Zürich (Switzerland); Mancini, L. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Safonova, M.; Subramaniam, A. [Indian Institute of Astrophysics, Bangalore 560 034 (India); Sereno, M. [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Gould, A. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Collaboration: PLAN Collaboration

    2014-03-10

    We present the final analysis of the observational campaign carried out by the PLAN (Pixel Lensing Andromeda) collaboration to detect a dark matter signal in form of MACHOs through the microlensing effect. The campaign consists of about 1 month/year observations carried out over 4 years (2007-2010) at the 1.5 m Cassini telescope in Loiano (Astronomical Observatory of BOLOGNA, OAB) plus 10 days of data taken in 2010 at the 2 m Himalayan Chandra Telescope monitoring the central part of M31 (two fields of about 13' × 12.'6). We establish a fully automated pipeline for the search and the characterization of microlensing flux variations. As a result, we detect three microlensing candidates. We evaluate the expected signal through a full Monte Carlo simulation of the experiment completed by an analysis of the detection efficiency of our pipeline. We consider both 'self lensing' and 'MACHO lensing' lens populations, given by M31 stars and dark matter halo MACHOs, in M31 and the Milky Way, respectively. The total number of events is consistent with the expected self-lensing rate. Specifically, we evaluate an expected signal of about two self-lensing events. As for MACHO lensing, for full 0.5(10{sup –2}) M {sub ☉} MACHO halos, our prediction is for about four (seven) events. The comparatively small number of expected MACHO versus self-lensing events, together with the small number statistics at our disposal, do not enable us to put strong constraints on that population. Rather, the hypothesis, suggested by a previous analysis, on the MACHO nature of OAB-07-N2, one of the microlensing candidates, translates into a sizeable lower limit for the halo mass fraction in form of the would-be MACHO population, f, of about 15% for 0.5 M {sub ☉} MACHOs.

  3. Multifocal intraocular lenses: An overview.

    Science.gov (United States)

    Alio, Jorge L; Plaza-Puche, Ana B; Férnandez-Buenaga, Roberto; Pikkel, Joseph; Maldonado, Miguel

    Multifocal intraocular lenses are increasingly used in the management of pseudophakic presbyopia. After multifocal intraocular lens implantation, most patients do not need spectacles or contact lenses and are pleased with the result. Complications, however, may affect the patient's quality of life and level of satisfaction. Common problems with multifocal lenses are blurred vision and photic phenomena associated with residual ametropia, posterior capsule opacification, large pupil size, wavefront anomalies, dry eye, and lens decentration. The main reasons for these are failure to neuroadapt, lens dislocation, residual refractive error, and lens opacification. To avoid patient dissatisfaction after multifocal intraocular lens implantation, it is important to consider preoperatively the patient's lifestyle; perform an exhaustive examination including biometry, topography, and pupil reactivity; and explain the visual expectations and possible postoperative complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Tuning Gravitationally Lensed Standard Sirens

    Science.gov (United States)

    Jönsson, J.; Goobar, A.; Mörtsell, E.

    2007-03-01

    Gravitational waves emitted by chirping supermassive black hole binaries could in principle be used to obtain very accurate distance determinations. Provided they have an electromagnetic counterpart from which the redshift can be determined, these standard sirens could be used to build a high-redshift Hubble diagram. Errors in the distance measurements will most likely be dominated by gravitational lensing. We show that the (de)magnification due to inhomogeneous foreground matter will increase the scatter in the measured distances by a factor of ~10. We propose to use optical and IR data of the foreground galaxies to minimize the degradation from weak lensing. We find that the net effect of correcting the estimated distances for lensing is comparable to increasing the sample size by a factor of 3 when using the data to constrain cosmological parameters.

  5. Gravitational lensing by exotic objects

    Science.gov (United States)

    Asada, Hideki

    2017-11-01

    This paper reviews a phenomenological approach to the gravitational lensing by exotic objects such as the Ellis wormhole lens, where the exotic lens objects may follow a non-standard form of the equation of state or may obey a modified gravity theory. A gravitational lens model is proposed in the inverse powers of the distance, such that the Schwarzschild lens and exotic lenses can be described in a unified manner as a one parameter family. As observational implications, the magnification, shear, photo-centroid motion and time delay in this lens model are discussed.

  6. Searches for New Physics in Top Events at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jung, A.W.; /Fermilab

    2012-06-01

    Recent results of searches for new physics in top events at the Tevatron are presented. In case of CDF three searches are discussed using 6 to 8.7 fb{sup -1} of data, with the latter being the final CDF data sample available for this kind of analysis. CDF carried out a search for Top + jet resonance production, dark matter production in association with single top and boosted tops. No signs of new physics are observed and instead upper limits are derived. D0 used 5.3 fb{sup -1} of data and searched for a narrow resonance in t{bar t} production and a time dependent t{bar t} cross section, which would reveal a violation of Lorentz invariance. However, no signs for deviations from standard model are seen and instead upper limits for non-standard model contributions are calculated.

  7. Correlations in bottom quark pair production at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Galyardt, Jason Edward [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2009-01-01

    I present an analysis of b$\\bar{b}$ pair production correlations, using dimuon-triggered data collected with the Collider Detector at Fermilab (CDF) in p$\\bar{p}$ collisions at √s = 1.96 TeV during Run II of the TeVatron. The leading order (LO) and next-to-leading order (NLO) b quark production processes are discriminated by the angular and momentum correlations between the b{bar b} pair. Track-level jets containing a muon are classified by b quark content and used to estimate the momentum vector of the progenitor b quark. The theoretical distributions given by the MC@NLO event generator are tested against the data.

  8. Search for quirks at the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Augustana Coll., Sioux Falls /Michigan U.; Alverson, G.; /Northeastern U.; Alves, G.A.; /Rio de Janeiro, CBPF /NIKHEF, Amsterdam

    2010-08-01

    We report results of a search for particles with anomalously high ionization in events with a high transverse energy jet and large missing transverse energy in 2.4 fb{sup -1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron p{bar p} collider. Production of such particles (quirks) is expected in scenarios with extra QCD-like SU(N) sectors, and this study is the first dedicated search for such signatures. We find no evidence of a signal and set a lower mass limit of 107 GeV for the mass of a charged quirk with strong dynamics scale {Lambda} in the range from 10 keV to 1 MeV.

  9. The PAX Toolkit and its Applications at Tevatron and LHC

    CERN Document Server

    Kappler, S; Felzmann, U; Hirschbuehl, D; Kirsch, M; Quast, G; Schmidt, A; Weng, J; Kappler, Steffen; Erdmann, Martin; Felzmann, Ulrich; Hirschbuehl, Dominic; Kirsch, Matthias; Quast, Guenter; Schmidt, Alexander; Weng, Joanna

    2006-01-01

    At the CHEP03 conference we launched the Physics Analysis eXpert (PAX), a C++ toolkit released for the use in advanced high energy physics (HEP) analyses. This toolkit allows to define a level of abstraction beyond detector reconstruction by providing a general, persistent container model for HEP events. Physics objects such as particles, vertices and collisions can easily be stored, accessed and manipulated. Bookkeeping of relations between these objects (like decay trees, vertex and collision separation, etc.) including deep copies is fully provided by the relation management. Event container and associated objects represent a uniform interface for algorithms and facilitate the parallel development and evaluation of different physics interpretations of individual events. So-called analysis factories, which actively identify and distinguish different physics processes and study systematic uncertainties, can easily be realized with the PAX toolkit. PAX is officially released to experiments at Tevatron and LHC...

  10. Beam-beam effects at the Fermilab Tevatron: Theory

    Directory of Open Access Journals (Sweden)

    T. Sen

    2004-04-01

    Full Text Available The Tevatron in Run II is operating with three trains of 12 bunches each. Long-range beam-beam interactions have been significant sources of beam loss and lifetime limitations of antiprotons. The dynamics due to the long-range beam-beam interactions depends on several beam parameters such as tunes, coupling, chromaticities, beam separations, intensities, and emittances. We have developed analytical tools to calculate, for example, amplitude dependent tune shifts and chromaticities, beam-beam induced coupling, and resonance driving terms. We report on these calculations and estimates of dynamic aperture and diffusion coefficients with long-term tracking. These theoretical results are compared with observations and used to predict performance at design values of beam parameters.

  11. Review of top quark production at LHC and Tevatron

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00419409; The ATLAS collaboration

    2016-01-01

    A summary of recent results on top quark production at LHC and Tevatron are presented in this paper. The measurements of top quark production were performed in various energies ($\\sqrt s$ = 1.96, 7, 8, 13 TeV) and initial states ($p \\bar{p}$ and $p p$) by the ATLAS, CDF, CMS, DØ and LHCb ex- periments. The measured top quark pair production cross-section is in good agreement with the standard model predictions in each energy region. Differential cross-sections were also measured and compared with several theoretical predictions. Most of the higher order QCD models reproduce the experimental data well, while a slight discrepancy in a certain phase space such as higher top quark $p_{T}$ region is observed. Electroweak single top quark production was also measured and the results are consistent with theoretical predictions at the various energies.

  12. Initial tests of an AC dipole for the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, R.; /Texas U.; Jansson, A.; /Fermilab; Kopp, S.; /Texas U.; Syphers, M.; /Fermilab

    2006-06-01

    The AC dipole is a device to diagnose transverse motions of a beam. It can achieve large-amplitude oscillations without two inevitable problems of conventional kicker/pinger magnets: decoherence and emittance growth. While not the first synchrotron to operate with an AC dipole, the Tevatron can now make use of its recently upgraded BPM system, providing unprecedented resolution for use with an AC dipole, to measure both linear and nonlinear properties of the accelerator. Plans are to provide AC dipole systems for both transverse degrees of freedom. Preliminary tests have been done using an audio power amplifier with an existing vertical pinger magnet, producing oscillation amplitudes up to 2{sigma} at 150 GeV. In this paper, we will present the configuration of this system. We also show the analysis of a first few data sets, including the direct measurement of beta functions at BPM locations.

  13. QCD analysis of W- and Z-boson production at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Camarda, S. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Belov, P. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Department of Physics, St. Petersburg State University, Ulyanovskaya 1, 198504, St. Petersburg (Russian Federation); Cooper-Sarkar, A. M. [Department of Physics, University of Oxford, Oxford (United Kingdom); Diaconu, C. [CPPM, IN2P3-CNRS, Univ. Mediterranee, Marseille (France); Glazov, A. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Guffanti, A. [Niels Bohr International Academy and Discovery Center, Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100, Copenhagen (Denmark); Jung, A. [FERMILAB, 60510, Batavia, IL (United States); Kolesnikov, V. [Joint Institute for Nuclear Research (JINR), Joliot-Curie 6, 141980, Dubna, Moscow Region (Russian Federation); Lohwasser, K. [Deutsches Elektronen-Synchrotron (DESY), Platanenallee 6, 15738, Zeuthen (Germany); Myronenko, V. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Olness, F. [Southern Methodist University, Dallas, TX (United States); Pirumov, H.; Plačakytė, R. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Radescu, V. [Physikalisches Institut, Universität Heidelberg, Heidelberg (Germany); Sapronov, A. [Joint Institute for Nuclear Research (JINR), Joliot-Curie 6, 141980, Dubna, Moscow Region (Russian Federation); Slominski, W. [M. Smoluchowski Institute of Physics, Jagiellonian University, Cracow (Poland); Starovoitov, P. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607, Hamburg (Germany); Sutton, M. [Department of Physics and Astronomy, University of Sussex, Sussex House, BN1 9RH, Brighton (United Kingdom)

    2015-09-28

    Recent measurements of the W-boson charge asymmetry and of the Z-boson production cross sections, performed at the Tevatron collider in Run II by the D0 and CDF collaborations, are studied using the HERAFitter framework to assess their impact on the proton parton distribution functions (PDFs). The Tevatron measurements, together with deep-inelastic scattering data from HERA, are included in a QCD analysis performed at next-to-leading order, and compared to the predictions obtained using other PDF sets from different groups. Good agreement between measurements and theoretical predictions is observed. The Tevatron data provide significant constraints on the d-valence quark distribution.

  14. QCD analysis of W- and Z-boson production at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Camarda, S.; Glazov, A.; Myronenko, V.; Pirumov, H.; Placakyte, R.; Starovoitov, P. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Belov, P. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); St. Petersburg State University, Department of Physics, St. Petersburg (Russian Federation); Cooper-Sarkar, A.M. [University of Oxford, Department of Physics, Oxford (United Kingdom); Diaconu, C. [Univ. Mediterranee, CPPM, IN2P3-CNRS, Marseille (France); Guffanti, A. [University of Copenhagen, Niels Bohr International Academy and Discovery Center, Niels Bohr Institute, Copenhagen (Denmark); Jung, A. [Fermilab, Batavia, IL (United States); Kolesnikov, V.; Sapronov, A. [Joint Institute for Nuclear Research (JINR), Dubna, Moscow Region (Russian Federation); Lohwasser, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Olness, F. [Southern Methodist University, Dallas, TX (United States); Radescu, V. [Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Slominski, W. [Jagiellonian University, M. Smoluchowski Institute of Physics, Cracow (Poland); Sutton, M. [University of Sussex, Department of Physics and Astronomy, Brighton (United Kingdom); Collaboration: HERAFitter developers' team

    2015-09-15

    Recent measurements of the W-boson charge asymmetry and of the Z-boson production cross sections, performed at the Tevatron collider in Run II by the D0 and CDF collaborations, are studied using the HERAFitter framework to assess their impact on the proton parton distribution functions (PDFs). The Tevatron measurements, together with deep-inelastic scattering data from HERA, are included in a QCD analysis performed at next-to-leading order, and compared to the predictions obtained using other PDF sets from different groups. Good agreement between measurements and theoretical predictions is observed. The Tevatron data provide significant constraints on the d-valence quark distribution. (orig.)

  15. Phase modulation of the bucket stops bunch oscillations at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Tan, C.Y.; Burov, A.; /Fermilab

    2012-04-02

    Bunches in the Tevatron are known to exhibit longitudinal oscillations which persist indefinitely. These oscillations are colloquially called 'dancing bunches.' Although the dancing proton bunches do not cause single bunch emittance growth or beam loss at injection, they lead to bunch lengthening at collisions. In Tevatron operations, a longitudinal damper has been built which stops this dance and damps out coupled bunch modes. Recent theoretical work predicts that the dance can also be stopped by an appropriate change in the bunch distribution. This paper describes the Tevatron experiments which support this theory.

  16. New results on the b^-+c meson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Rahaman, M.A.; /Pittsburgh U.

    2006-09-01

    The authors present recent results on B{sub c}{sup -} meson from the Tevatron. The B{sub c}{sup -} meson has been observed in semileptonic decays, B{sub c}{sup -} {yields} J/{psi}{ell}{sup -} {nu}X, both by CDF and D0 experiments at a significance larger than 5{sigma}. The D0 experiment has used the candidates in B{sub c}{sup -} {yields} J/{psi}{mu}{sup -} {nu}X decay to extract the mass and lifetime of B{sub c}{sup -} meson. The CDF experiment has used both electron and muon channel candidates in B{sub c}{sup -} {yields} J/{psi}{ell}{sup -} {nu}X decays to measure the relative production times branching ratio with respect to B{sup -} {yields} J/{psi}K{sup -} decay and also measured the lifetime of B{sub c}{sup -} meson in electron channel as {tau}(B{sub c}{sup -}) = 0.463{sub -0.055}{sup +0.073} {+-} 0.036 ps. The CDF experiment has also observed B{sub c}{sup -} {yields} J/{psi}{pi}{sup -} decay with a significance exceeding 6.5{sigma} and has measured the mass of B{sub c}{sup -} meson as M(B{sub c}{sup -}) = 6276.5 {+-} 4.0 {+-} 2.7 MeV/c{sup 2}.

  17. Precise measurements of the $W$ mass at the Tevatron and indirect constraints on the Higgs mass

    Energy Technology Data Exchange (ETDEWEB)

    Lopes de Sa, Rafael

    2012-04-01

    I describe the latest D0 and CDF W boson mass measurements. The D0 measurement is performed with 4.3 fb{sup -1} of integrated luminosity in the electron decay channel with a data set of 1.68 x 10{sup 8} W candidates. The value of the W boson mass measured by D0 is M{sub W} = 80.375 {+-} 0.023 GeV when combined with the previously analyzed 1 fb{sup -1} of integrated luminosity. The CDF measurement uses 2.2 fb{sup -1} of integrated luminosity in both electron and muon decay channels with a total of 1.1 x 10{sup 8} W candidates. The value of the W boson mass measured by CDF is M{sub W} = 80.387 {+-} 0.019 GeV. I report the combination of these two measurements with previous Tevatron measurements and with the LEP measurements of the W boson mass. The new world average is M{sub W} = 80.385 {+-} 0.015GeV. I discuss the implications of the new measurement to the indirect measurement of the Standard Model Higgs boson mass.

  18. Optics Demonstrations Using Cylindrical Lenses

    Science.gov (United States)

    Ivanov, Dragia; Nikolov, Stefan

    2015-01-01

    In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

  19. Weak lensing and cosmological investigation

    CERN Document Server

    Acquaviva, V

    2005-01-01

    In the last few years the scientific community has been dealing with the challenging issue of identifying the dark energy component. We regard weak gravitational lensing as a brand new, and extremely important, tool for cosmological investigation in this field. In fact, the features imprinted on the cosmic microwave background radiation by the lensing from the intervening distribution of matter represent a pretty unbiased estimator, and can thus be used for putting constraints on different dark energy models. This is true in particular for the magnetic-type B-modes of CMB polarization, whose unlensed spectrum at large multipoles (l approximately=1000) is very small even in presence of an amount of gravitational waves as large as currently allowed by the experiments: therefore, on these scales the lensing phenomenon is the only responsible for the observed power, and this signal turns out to be a faithful tracer of the dark energy dynamics. We first recall the formal apparatus of the weak lensing in extended t...

  20. Military Research with Contact Lenses

    Science.gov (United States)

    1993-03-01

    glass scleral lenses. In his study, he subjected 10 volunteers to various simulated altitudes in a hypobaric chamber and examined the subjects with a...Avenue Harry Diamond Laboratories Alexandria, VA 22333 ATTN: Technical Information Branch 2800 Powder Mill Road Commandant Adelphi, MD 20783-1197 U.S

  1. Gravitational Lensing of Supernova Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Mena, Olga; /Fermilab /Rome U.; Mocioiu, Irina; /Penn State U.; Quigg, Chris; /Fermilab

    2006-10-01

    The black hole at the center of the galaxy is a powerful lens for supernova neutrinos. In the very special circumstance of a supernova near the extended line of sight from Earth to the galactic center, lensing could dramatically enhance the neutrino flux at Earth and stretch the neutrino pulse.

  2. The Optical Gravitational Lensing Experiment

    Science.gov (United States)

    Udalski, A.; Szymanski, M.; Kaluzny, J.; Kubiak, M.; Mateo, Mario

    1992-01-01

    The technical features are described of the Optical Gravitational Lensing Experiment, which aims to detect a statistically significant number of microlensing events toward the Galactic bulge. Clusters of galaxies observed during the 1992 season are listed and discussed and the reduction methods are described. Future plans are addressed.

  3. Measurement of the top quark properties at the Tevatron and the LHC

    CERN Document Server

    INSPIRE-00040958

    2014-01-01

    Almost two decades after its discovery at Fermilab's Tevatron collider experiments, the top quark is still under the spotlight due to its connections to some of the most interesting puzzles in the Standard Model. The Tevatron has been shut down two years ago, yet some interesting results are coming out of the CDF and D0 collaborations. The LHC collider at CERN produced two orders of magnitude more top quarks than Tevatron's, thus giving birth to a new era for top quark physics. While the LHC is also down at the time of this writing, many top quark physics results are being extracted out of the 7\\,TeV and 8\\,TeV proton proton collisions by the ATLAS and CMS collaborations, and many more are expected to appear before the LHC will be turned on again sometime in 2015. These proceedings cover a selection of recent results produced by the Tevatron and LHC experiments.

  4. Design Report Tevatron 1 Project, Second Printing November 1982 (Revised April 1983)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1982-10-01

    This report describes the design of the Tevatron I Project, which will enable Fermilab to produce proton-antiproton collsions in the Tevatron accelerator. Center-of-mass energies near 2 TeV, by far the highest available anywhere in the world for high-energy physics research until at least the decade of the 1990's, will provide enormous opportunities for exciting new physics.

  5. EDITORIAL: Focus on Gravitational Lensing

    Science.gov (United States)

    Jain, Bhuvnesh

    2007-11-01

    Gravitational lensing emerged as an observational field following the 1979 discovery of a doubly imaged quasar lensed by a foreground galaxy. In the 1980s and '90s dozens of other multiply imaged systems were observed, as well as time delay measurements, weak and strong lensing by galaxies and galaxy clusters, and the discovery of microlensing in our galaxy. The rapid pace of advances has continued into the new century. Lensing is currently one of best techniques for finding and mapping dark matter over a wide range of scales, and also addresses broader cosmological questions such as understanding the nature of dark energy. This focus issue of New Journal of Physics presents a snapshot of current research in some of the exciting areas of lensing. It provides an occasion to look back at the advances of the last decade and ahead to the potential of the coming years. Just about a decade ago, microlensing was discovered through the magnification of stars in our galaxy by invisible objects with masses between that of Jupiter and a tenth the mass of the Sun. Thus a new component of the mass of our galaxy, dubbed MACHOs, was established (though a diffuse, cold dark matter-like component is still needed to make up most of the galaxy mass). More recently, microlensing led to another exciting discovery—of extra-solar planets with masses ranging from about five times that of Earth to that of Neptune. We can expect many more planets to be discovered through ongoing surveys. Microlensing is the best technique for finding Earth mass planets, though it is not as productive overall as other methods and does not allow for follow up observations. Beyond planet hunting, microlensing has enabled us to observe previously inaccessible systems, ranging from the surfaces of other stars to the accretion disks around the black holes powering distant quasars. Galaxies and galaxy clusters at cosmological distances can produce dramatic lensing effects: multiple images of background galaxies

  6. An alternative approach to bandage contact lenses.

    Science.gov (United States)

    Gupta, S; Arora, R; Dass Sota, L; Kumar, M

    1998-04-01

    Therapeutic bandage contact lenses have been used in the management of a variety of corneal and anterior segment disorders. However, clinical experience with the therapeutic use of disposable contact lenses is limited. The present study was designed to evaluate the efficacy of disposable contact lenses as bandage lenses in anterior segment disorders. We fit 45 patients who had various corneal and anterior segment disorders with disposable contact lenses (42% etafilcon A and 58% water content). We used this lens as a healing and surgical adjunct and for structural support and symptomatic relief. Patients were followed for a minimum period of 3 months. Therapeutic efficacy and complications were evaluated. Eighty-two percent of patients were fit successfully. Ninety-one percent of the successfully fit patients were therapeutic successes. Disposable lenses were found to be very useful in the management of epithelial abnormalities and as surgical adjuncts. Dry eye was the most frequent cause of contact lens associated therapeutic failure. Complications included contact lens deposits, lens loss, and corneal neovascularization. The use of disposable lenses was most effective in conditions requiring short-term lens use where one to two lens applications were sufficient to allow healing, making disposable lenses a very convenient and cost-effective alternative to conventional therapeutic bandage contact lenses. For reasons of cost, disposable lenses were not a viable alternative in conditions requiring therapeutic lens use for long periods of time.

  7. Durability of coated CR-39 industrial lenses.

    Science.gov (United States)

    Chou, B Ralph; Hovis, Jeffery K

    2003-10-01

    To study the effect of coatings on the resistance of CR-39 industrial plano lenses to ballistic impacts and abrasion from fine particles. Twelve groups of CR-39 lenses with various scratch-resistant (SR) or combinations of scratch-resistant and antireflective (SR-AR) coatings were mounted in metal industrial spectacle frames. The ZEST protocol was used to determine the mean impact speed for breakage of each lens group using the Canadian Standards Association ballistic test protocol. One pair of lenses from each group was tested for abrasion resistance using the falling sand method. Abrasion resistance was ranked by the degree of haze observed by three independent observers. Uncoated lenses had the best impact resistance and worst abrasion resistance. SR-coated lenses showed mild to moderate reductions in impact resistance, with no correlation between impact and abrasion resistance. SR-AR-coated lenses had very good abrasion resistance, but severely reduced impact resistance. Most SR-coated CR-39 lenses have a high probability of meeting the high-velocity impact resistance requirement of industrial lenses, whereas CR-39 lenses with SR-AR coats are too fragile to be used in industrial spectacles. As a group, the SR-AR coating tended to be more resistant to abrasion by fine particles and less resistant to ballistic impacts, but the abrasion resistance of the SR-coated lenses was more variable, and, thus, overall there was no significant correlation between impact resistance and abrasion resistance.

  8. Effects of multipurpose solutions on the adhesion of Acanthamoeba to rigid gas permeable contact lenses.

    Science.gov (United States)

    Lee, Ga-Hyun; Yu, Hak-Sun; Lee, Ji-Eun

    2016-03-01

    To evaluate the effect of multipurpose contact lens care solutions (MPSs) on the adhesion of Acanthamoeba to rigid gas permeable (RGP) contact lenses. Acanthamoeba castellanii (AC) trophozoites were inoculated onto untreated RGP contact lenses (FP, Extra, or Menicon Z), and numbers of trophozoites adhering to lenses were counted under a phase contrast microscope at 18 h post-inoculation (controls). Similarly, adhering trophozoites were counted at 6 h post-inoculation on each of the three RGP lens types with one of three MPSs (Boston Simplus, Menicare Plus, and O2 Care). Scanning electron microscopic examinations were performed to compare lens surfaces. Adhesion of AC trophozoites to untreated FP was greater than to untreated Extra or Menicon Z. Surfaces of Extra and Menicon Z lenses were waxier, smoother, and more homogeneous than those of FP lenses. After treatment with Boston Simplus, adhesion of AC trophozoites was significantly reduced for all lens types as compared with controls (p lenses only as compared with controls (p lenses depended on lens surfaces. Boston Simplus reduced the adhesion rate of AC trophozoites more than Menicare Plus or O2 Care. Appropriate RGP lens and MPS selection could decrease the prevalence of Acanthamoeba keratitis. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

  9. Gravitational lensing by rotating wormholes

    Science.gov (United States)

    Jusufi, Kimet; Ã-vgün, Ali

    2018-01-01

    In this paper the deflection angle of light by a rotating Teo wormhole spacetime is calculated in the weak limit approximation. We mainly focus on the weak deflection angle by revealing the gravitational lensing as a partially global topological effect. We apply the Gauss-Bonnet theorem (GBT) to the optical geometry osculating the Teo-Randers wormhole optical geometry to calculate the deflection angle. Furthermore we find the same result using the standard geodesic method. We have found that the deflection angle can be written as a sum of two terms, namely the first term is proportional to the throat of the wormhole and depends entirely on the geometry, while the second term is proportional to the spin angular momentum parameter of the wormhole. A direct observation using lensing can shed light and potentially test the nature of rotating wormholes by comparing with the black holes systems.

  10. Measurements of top-quark properties at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Andreas Werner [Fermilab

    2013-07-30

    Recent measurements of top-quark properties at the Tevatron are presented. CDF uses data corresponding up to 9.0 fb-1 to measure the ratio R of the branching fractions , the branching fraction for top-quarks decaying into τ leptons and the cross section for the production of an additional γ in t production. The results from all these measurements agree well with their respective Standard Model expectation. DØ uses 5.3 fb-1 of data to measure the t cross section as a function of the time. A time dependency would imply Lorentz invariance violation as implemented by the Standard Model extension. No time dependency is observed and DØ sets first limits in the top-quark sector for Lorentz invariance violation. DØ also determines indirectly the top quark width using the results of earlier measurements at DØ. The measured top quark width is in agreement with the SM expectation and does not show any hints for new physics contributions.

  11. Charmed meson and onium production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    T. Nakaya

    2000-12-20

    The authors report recent results of D*{sup {+-}} meson, J/{psi} and {Upsilon} production at the Fermilab Tevatron. They observe about 8,000 D*{sup {+-}} mesons reconstructed in the decay chain of D* {r_arrow} D{sub {pi}}{sup 0}, D{sup 0} {r_arrow} K{mu}+X. They measure the integrated D*{sup +} production cross section to be 347 {+-} 65(stat.) {+-} 58(sys.) nb for the rapidity range {vert_bar}{eta}(D*{sup +}){vert_bar} < 1.0 and the transverse momentum range p{sub T} (D*{sup +}) > 10 GeV/c. The measurement is slightly higher than the theoretical prediction, especially at lower pT range. We also measure the polarization of J/{psi} at production and find that the measured transverse polarization is not well explained by the color-octet model proposed to explain the anomalously high J/{psi} production cross section. We also present a new result on {Upsilon} production and polarization. Production of the {Upsilon} is consistent with being unpolarized.

  12. Neutrino Production of Same Sign Dimuons at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Sandler, Pamela Helen [Univ. of Wisconsin, Madison, WI (United States)

    1992-01-01

    The rate of neutrino and antineutrino induced same-sign dimuon production was measured using a sample of 220 μ-μ- events and 15 μ+μ+ events, normalized to 1.5 million neutrino-induced charged-current events and 0.3 million antineutrino-induced events with energies between 30 GeV and 600 GeV. The data was obtained with the Chicago-Columbia- Fermilab-Rochester neutrino detector at the Fermilab Tevatron during two experiments, E744 and E770. The CCFR detector is a combined steel target and calorimeter which is followed by a muon-momentum spectrometer. After background subtraction, the prompt rate of same-sign dimuon production is (0.53±0.24)x$10^{-4}$ per charged-current event for neutrinos and (0.52±0.33)x $10^{-4}$ per charged-current events for antineutrinos. These rates are consistent with Standard Model predictions for cc gluon bremsstrahlung and with zero. The kinematic distributions of the same-sign dimuon signal are consistent with those of the nonprompt background due to meson decays in the hadron shower of a charged-current events and cc gluon bremsstrahlung.

  13. Optimal Weak Lensing Skewness Measurements

    OpenAIRE

    Zhang, Tong-Jie; Pen, Ue-Li; Zhang, Pengjie; Dubinski, John

    2003-01-01

    Weak lensing measurements are entering a precision era to statistically map the distribution of matter in the universe. The most common measurement has been of the variance of the projected surface density of matter, which corresponds to the induced correlation in alignments of background galaxies. This measurement of the fluctuations is insensitive to the total mass content, like using waves on the ocean to measure its depths. But when the depth is shallow as happens near a beach, waves beco...

  14. [Contact lenses: indications and limits].

    Science.gov (United States)

    Neuhann, T

    1979-10-04

    Contact lens wear may be indicated for cosmetic, professional, optical or therapeutic reasons. For each of these indications the arguments are given, why and when contact lenses are better than spectacle correction and which possibilities there are. Contact lens wear is contraindicated in certain eye diseases and in the case of problems of handling and hygiene. The author's preferences concerning the different contact lens materials are summarized briefly.

  15. Uncontrolled Selling of Contact Lenses

    Directory of Open Access Journals (Sweden)

    Cem Sundu

    2015-05-01

    Full Text Available Objectives: To evaluate the opticians’ perspective about selling and applying contact lenses (CL in the provincial centre of Mersin. Materials and Methods: Twenty opticians who work in the 4 main districts in the provincial centre of Mersin were included in the study. A questionnaire form which was prepared before was filled out by the participants. Results: Seventy-eight percent of the opticians were selling CL without prescription, whereas 25% also carried out its fitting. Seventyfive percent of the participants did not get any education about contact lenses, while 65% of them were feeling themselves disqualified about CLs. Furthermore, half of the participants did not have enough knowledge about the complications associated with CL usage and 75% of them wanted to receive information about CLs. Conclusion: As a result of the questionnaire, we found out that a significant part of the participants were both selling and fitting contact lenses without prescription. We believe that auditing the opticians is as important as educating the contact lens users. (Turk J Ophthalmol 2015; 45: 102-104

  16. 30 CFR 18.30 - Windows and lenses.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Windows and lenses. 18.30 Section 18.30 Mineral... § 18.30 Windows and lenses. (a) MSHA may waive testing of materials for windows or lenses except headlight lenses. When tested, material for windows or lenses shall meet the test requirements prescribed in...

  17. Mechanically triggered solute uptake in soft contact lenses.

    Science.gov (United States)

    Tavazzi, Silvia; Ferraro, Lorenzo; Fagnola, Matteo; Cozza, Federica; Farris, Stefano; Bonetti, Simone; Simonutti, Roberto; Borghesi, Alessandro

    2015-06-01

    Molecular arrangement plays a role in the diffusion of water and solutes across soft contact lenses. In particular, the uptake of solutes in hydrated contact lenses can occur as long as free water is available for diffusion. In this work, we investigated the effect of mechanical vibrations of low frequency (200 Hz) on the solute uptake. Hyaluronan, a polysaccharide of ophthalmic use, was taken as example of solute of interest. For a specific water-hydrated hydrogel material, differential scanning calorimetry experiments showed that a large fraction of the hydration water accounted for loosely-bound water, both before and after one week of daily-wear of the lenses. The size (of the order of magnitude of few hundreds of nanometers) of hyaluronan in aqueous solution was found to be less than the size of the pores of the lens observed by scanning electron microscopy. However, solute uptake in already-hydrated lenses was negligible by simple immersion, while a significant increase occurred under mechanical vibrations of 200 Hz, thus providing experimental evidence of mechanically triggered enhanced solute uptake, which is attributed to the release of interfacial loosely-bound water. Also other materials were taken into consideration. However, the effectiveness of mechanical vibrations for hyaluronan uptake is restricted to lenses containing interfacial loosely-bound water. Indeed, loosely-bound water is expected to be bound to the polymer with bonding energies of the order of magnitude of 10-100 J/g, which are compatible with the energy input supplied by the vibrations. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Disposable and frequent replacement contact lenses.

    Science.gov (United States)

    Ehlers, William H; Donshik, Peter C; Suchecki, Jeanine K

    2003-09-01

    Disposable and frequent replacement contact lenses dominate the marketplace. They are available in a wide variety of parameters for use in refractive errors, including myopia, hyperopia, astigmatism, and presbyopia. They are convenient and affordable and lend themselves to most wearing modalities, including daily wear, flexible wear, and extended wear for up to 30 days. In addition, they have been shown to be the most trouble-free contact lens wear modality for daily wear or extended wear. They are an appropriate choice for patients who desire occasional contact lens wear and have gained wide acceptance as therapeutic bandage contact lenses. Disposable and frequent replacement lenses will remain important modalities for some time to come as the variety of contact lenses and contact lens parameters that are offered continue to expand. New contact lens varieties, such as the high-Dk silicone hydrogel lenses, will further expand the role of these contact lenses in vision correction.

  19. Characterization of sand lenses embedded in tills

    DEFF Research Database (Denmark)

    Kessler, Timo Christian; Klint, K.E.S.; Nilsson, B.

    2012-01-01

    Tills dominate large parts of the superficial sediments on the Northern hemisphere. These glacial diamictons are extremely heterogeneous and riddled with fractures and lenses of sand or gravel. The frequency and geometry of sand lenses within tills are strongly linked to glaciodynamic processes...... occurring in various glacial environments. This study specifically focuses on the appearance and spatial distribution of sand lenses in tills. It introduces a methodology on how to measure and characterize sand lenses in the field with regard to size, shape and degree of deformation. A set of geometric...... parameters is defined to allow characterization of sand lenses. The proposed classification scheme uses a stringent terminology to distinguish several types of sand lenses based on the geometry. It includes sand layers, sand sheets, sand bodies, sand pockets and sand stringers. The methodology has been...

  20. Planck 2015 results. XV. Gravitational lensing

    CERN Document Server

    Ade, P.A.R.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A.J.; Barreiro, R.B.; Bartlett, J.G.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J.J.; Bonaldi, A.; Bonavera, L.; Bond, J.R.; Borrill, J.; Bouchet, F.R.; Boulanger, F.; Bucher, M.; Burigana, C.; Butler, R.C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H.C.; Christensen, P.R.; Church, S.; Clements, D.L.; Colombi, S.; Colombo, L.P.L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B.P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R.D.; Davis, R.J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J.M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T.A.; Eriksen, H.K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A.A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K.M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J.E.; Hansen, F.K.; Hanson, D.; Harrison, D.L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S.R.; Hivon, E.; Hobson, M.; Holmes, W.A.; Hornstrup, A.; Hovest, W.; Huffenberger, K.M.; Hurier, G.; Jaffe, A.H.; Jaffe, T.R.; Jones, W.C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T.S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C.R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P.B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P.M.; Macías-Pérez, J.F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P.G.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P.R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J.A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C.B.; Nørgaard-Nielsen, H.U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C.A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G.W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J.P.; Reach, W.T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J.A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Seiffert, M.D.; Shellard, E.P.S.; Spencer, L.D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J.A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L.A.; Wandelt, B.D.; Wehus, I.K.; White, M.; Yvon, D.; Zacchei, A.

    2016-01-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40 sigma), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator we detect lensing at a significance of 5 sigma. We cross-check the accuracy of our measurement using the wide frequency coverage and complementarity of the temperature and polarization measurements. Public products based on this measurement include an estimate of the lensing potential over approximately 70% of the sky, an estimate of the lensing potential power spectrum in bandpowers for the multipole range 40lensing potential power spectrum and that found in the best-fitting LCDM model based on the Planck temperature and polarization power spectra. Using the lensing likelihood alone we obtain a percent-level measurement of ...

  1. Nanofocusing Refractive X-Ray Lenses

    OpenAIRE

    Boye, Pit

    2010-01-01

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive x-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution x-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. ...

  2. Search for the single top quarks produced in s-channel via electroweak interactions at √s = 1.96 at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Jabeen, Shabnam [Univ. of Kansas, Lawrence, KS (United States)

    2006-01-01

    The authors present a search for single top quarks produced in the s-channel electroweak production mode. The search is performed in the electron+jets decay channels, with one or more secondary-vertex tagged jets to indicate the presence of a b-jet and hence improving the signal:background ratio. Separation between signal and background is further enhanced by the use of Feed Forward Neural networks. 360 pb-1 of Run II data used for this analysis was delivered by the Tevatron, and collected by D0 between August 2002 and August 2004. The resulting 95% confidence level upper limit is 4 pb.

  3. 2007 2008 ACADEMIC TRAINING PROGRAMME: Tevatron: The Cinderella Story or The Art Of Collider Commissioning

    CERN Multimedia

    2007-01-01

    LECTURE SERIES 01, 03, 04, 05 October 2007 Main Auditorium, bldg. 500 Tevatron: The Cinderella Story or The Art Of Collider Commissioning V. SHILTSEV / Fermi National Accelerator Laboraty, Batavia IL, USA The Tevatron Collider at Fermilab (Batavia, IL, USA) is the world’s highest energy particle collider at 1.8TeV c.m.e. The machine was a centerpiece of the US and world’s High Energy Physics for many years. Currently, the Tevatron is in the last years of its operation in so-called Run II which started 2001 and is tentatively scheduled to end in 2010. In this lecture series, we’ll try to learn from the exciting story of the Tevatron Collider Run II: the story of long preparations, great expectations, initial difficulties, years of "blood and sweat", continuous upgrades, exceeding its goals, high emotions, tune-up of accelerator organization for "combat fighting". The lectures will cover Introduction to the Tevatron, its history and Run II; "Plumbing"...

  4. Studies of the Chromaticity, Tune, and Coupling Drift in the Tevatron

    CERN Document Server

    Martens, Michael A; Bauer, Pierre; Shiltsev, Vladimir; Velev, Gueorgui

    2005-01-01

    Chromaticity drift is a well-known and more or less well-understood phenomenon in superconducting colliders such as the Tevatron. Less known is the effect of tune and coupling drift, also observed in the Tevatron during injection. These effects are caused by field drifts in the superconducting magnets. Understanding of the behavior of the tune, coupling, and chromaticity at the start of the ramp is an important part of understanding the observed 5-10% loss in beam intensity at the start of the Tevatron ramp. In addition modifications in the Tevatron shot set-up procedure are being implemented to allow for a gain in integrated luminosity. In this context we conducted several beam-studies, during the period of April to August 2004, in which we measured the drift in the Tevatron chromaticity, tune and coupling during the injection porch. In some case we also measured the snapback at the start of the ramp. We will present the results of these studies data and put them into context of the results of off-line magne...

  5. Measuring the top anti-t Production Cross-Section in the Electron + Jets Channel in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV with the D0 Detector at the Tevatron: A Monte Carlo Study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Su-Jung; /Bonn U.

    2004-02-01

    The measurement of the t{bar t} production cross section at {radical}s = 1.96 TeV using the final state with an electron and jets is studied with Monte Carlo event samples. All methods used in the real data analysis to measure efficiencies and to estimate the background contributions are examined. The studies focus on measuring the electron reconstruction efficiencies as well as on improving the electron identification and background suppression. With a generated input cross section of 7 pb the following result is obtained: {sigma}{sub t{bar t}} = (7 {+-} 1.63(stat){sub -1.14}{sup +0.94} (syst)) pb.

  6. Observation of Central Exclusive Diphoton Production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Brucken, Jens Erik [Univ. of Helsinki (Finland); Helsinki Inst. of Physics (Finland)

    2013-01-01

    We have observed exclusive γγ production in proton-antiproton collisions at the Tevatron at √ s = 1.96 TeV. We use data corresponding to 1.11 ± 0.07 fb-1 integrated luminosity taken by the Run II Collider Detector at Fermilab, with a trigger requiring two electromagnetic showers, each with transverse energy ET > 2 GeV, and vetoing on hits in the forward beam shower counters. We select events with two electromagnetic showers, each with transverse energy ET > 2.5 GeV and pseudorapidity |η| < 1.0, with no other particles detected in -7.4 < η < +7.4. The two showers have similar ET and an azimuthal angle separation Δφ ~ π; we find 34 events with exactly two matching charged particle tracks, agreeing with expectations for the QED process p¯p → p+e+e- + ¯p by two photon exchange; and we find 43 events with no tracks. The latter are candidates for the exclusive process p¯p → p + γγ + ¯p by double pomeron exchange. We use the strip and wire chambers at the longitudinal shower maximum position within the calorimeter to measure a possible exclusive background from IP + IP → π0π0, and conclude that it is consistent with zero and is < 15 events at 95% C.L. The measured cross section is σγγ,excl(|η| < 1, ET (γ) > 2.5 GeV) = 2.48 +0.40 -0.35(stat) +0.40 -0.51(syst) pb and in agreement with the theoretical predictions. This process is closely related to exclusive Higgs boson production pp → p + H + p at the Large Hadron Collider. The observation of the exclusive production of diphotons shows that exclusive Higgs production can happen and could be observed with a proper experimental setup.

  7. Age-related compaction of lens fibers affects the structure and optical properties of rabbit lenses

    Directory of Open Access Journals (Sweden)

    Al-Ghoul Walid M

    2007-12-01

    Full Text Available Abstract Background The goal of this investigation was to correlate particular age-related structural changes (compaction to the amount of scatter in rabbit lenses and to determine if significant fiber compaction occurred in the nuclear and inner cortical regions. Methods New Zealand White rabbits at 16–20 months old (adult; n = 10 and at 3.5–4 years old (aged; n = 10 were utilized for this study. Immediately after euthanising, scatter was assessed in fresh lenses by low power helium-neon laser scan analysis. Scatter data was analyzed both for whole lenses and regionally, to facilitate correlation with morphometric data. After functional analysis, lenses were fixed and processed for scanning electron microcopy (SEM; right eyes and light microscopy (LM; left eyes. Morphometric analysis of SEM images was utilized to evaluate compaction of nuclear fibers. Similarly, measurements from LM images were used to assess compaction of inner cortical fibers. Results Scatter was significantly greater in aged lenses as compared to adult lenses in all regions analyzed, however the difference in the mean was slightly more pronounced in the inner cortical region. The anterior and posterior elliptical angles at 1 mm (inner fetal nucleus were significantly decreased in aged vs. adult lenses (anterior, p = 0.040; posterior, p = 0.036. However, the average elliptical angles at 2.5 mm (outer fetal nucleus were not significantly different in adult and aged lenses since all lenses examined had comparable angles to inner fetal fibers of aged lenses, i.e. they were all compacted. In cortical fibers, measures of average cross-sectional fiber area were significantly different at diameters of both 6 and 7 mm as a function of age (p = 0.011 and p = 0.005, respectively. Accordingly, the estimated fiber volume was significantly decreased in aged as compared to adult lenses at both 6 mm diameter (p = 0.016 and 7 mm diameter (p = 0.010. Conclusion Morphometric data indicates

  8. The Scales of Gravitational Lensing

    Directory of Open Access Journals (Sweden)

    Francesco De Paolis

    2016-03-01

    Full Text Available After exactly a century since the formulation of the general theory of relativity, the phenomenon of gravitational lensing is still an extremely powerful method for investigating in astrophysics and cosmology. Indeed, it is adopted to study the distribution of the stellar component in the Milky Way, to study dark matter and dark energy on very large scales and even to discover exoplanets. Moreover, thanks to technological developments, it will allow the measure of the physical parameters (mass, angular momentum and electric charge of supermassive black holes in the center of ours and nearby galaxies.

  9. Comparison of spectacle classical progressive and office progressive lenses.

    Science.gov (United States)

    Kozlík, Marek; Knollová, Libuse Nováková

    2013-04-01

    This paper elaborates on analysis of progressive spectacle lenses, to correct presbyopia, which are nowadays offered at the market. The paper describes different types of progressive lenses, their parameters, length and width of their progressive segments. It also describes degressive spectacles lenses--progressive lenses on middle and near distance. The main part of the paper is a comparison of functional differences among different types of progressive spectacles lenses. The paper also addresses correctness of choice of progressive lenses for different works and professions. Lastly, it elaborates on differences of centration of different types of progressive lenses and parameters for correct choice of glasses frame for progressive spectacles lenses.

  10. CERN scientists take part in the Tevatron Run II performance review committee

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Tevatron Run II is under way at Fermilab, exploring the high-energy frontier with upgraded detectors that will address some of the biggest questions in particle physics.Until CERN's LHC switches on, the Tevatron proton-antiproton collider is the world's only source of top quarks. It is the only place where we can search for supersymmetry, for the Higgs boson, and for signatures of additional dimensions of space-time. The US Department of Energy (DOE) recently convened a high-level international review committee to examine Fermilab experts' first-phase plans for the accelerator complex. Pictured here with a dipole magnet in CERN's LHC magnet test facility are the four CERN scientists who took part in the DOE's Tevatron review. Left to right: Francesco Ruggiero, Massimo Placidi, Flemming Pedersen, and Karlheinz Schindl. Further information: CERN Courier 43 (1)

  11. Phakic intraocular lenses and their special indications

    Directory of Open Access Journals (Sweden)

    Roberto Pineda

    2016-01-01

    Full Text Available Phakic intraocular lenses revolutionize refractive surgery and continue to serve as an excellent option for vision correction in patients who are not ideal candidates for laser vision correction. This article will review special indications of phakic intraocular lenses in the clinical practice.

  12. Planck 2015 results: XV. Gravitational lensing

    DEFF Research Database (Denmark)

    Ade, P. A R; Aghanim, N.; Arnaud, M.

    2016-01-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40σ), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator, we detect lensing at a significance of 5σ. We...

  13. Modern scleral lenses part I: clinical features.

    NARCIS (Netherlands)

    Visser, E.S.; Visser, R.; Lier, H.J.J. van; Otten, H.M.

    2007-01-01

    PURPOSE: To evaluate the indications for modern scleral lenses and their clinical performance in patients who were fitted with scleral lenses at the authors' practices. METHODS: In this cross-sectional survey, all the necessary data were obtained at the first follow-up visit during the 5-month study

  14. Ocular Straylight with Different Multifocal Contact Lenses

    NARCIS (Netherlands)

    Łabuz, Grzegorz; López-Gil, Norberto; van den Berg, Thomas J T P; Vargas-Martín, Fernando

    2017-01-01

    PURPOSE: Multifocal contact lenses have been growing in popularity as a modality to correct presbyopic eyes, although visual side effects such as disability glare have been reported. The objective of this study was to investigate the effect of multifocal contact lenses on disability glare by means

  15. Soft Lenses | Kuming | South African Medical Journal

    African Journals Online (AJOL)

    A series of cases fitted with Bionite soft lenses is described. Good results were obtained in bullous keratopathy, dry eyes, early and moderately advanced Stevens-Johnson syndrome and pemphigoid, and some cases of indolent corneal ulcers. The lenses appear to be a most effective replacement for tarsorrhaphy, haptic ...

  16. Electron and photon identification in the D0 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Borysova, M.; Brandt, A.; Brandt, O.; Brock, R.; Bross, A.; Brown, D.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M. -C.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duperrina, A.; Dutt, S.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, V. N.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J. -F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jeong, M. S.; Jesik, R.; Jiang, P.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kajfasz, E.; Karmanov, D.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Lammers, S.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nguyen, H. T.; Nunnemann, T.; Orduna, J.; Osman, N.; Osta, J.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M. -A.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Raja, R.; Ratoff, P. N.; Razumov, I.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santos, A. S.; Savage, G.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Simak, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stoyanova, D. A.; Strauss, M.; Suter, L.; Svoisky, P.; Titov, M.; Tokmenin, V. V.; Tsai, Y. -T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verkheev, A. Y.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Williams, M. R. J.; Wilson, G. W.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yang, S.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yin, H.; Yip, K.; Youn, S. W.; Yu, J. M.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.

    2014-06-01

    The electron and photon reconstruction and identification algorithms used by the D0 Collaboration at the Fermilab Tevatron collider are described. The determination of the electron energy scale and resolution is presented. Studies of the performance of the electron and photon reconstruction and identification are summarized.

  17. Acanthamoeba keratitis related to cosmetic contact lenses.

    Science.gov (United States)

    Lee, Jong Soo; Hahn, Tae Won; Choi, Si Hwan; Yu, Hak Sun; Lee, Ji-Eun

    2007-11-01

    We report a rare case of Acanthamoeba keratitis related to cosmetic contact lenses in both eyes. A 17-year-old girl with a history of wearing cosmetic contact lenses presented with keratitis. She purchased cosmetic contact lenses via the Internet, and followed a contact lens care system irregularly, occasionally using tap water. Cell culture was performed on samples collected from a corneal scraping, the contact lenses and the storage cases. The isolated organism was Acanthamoeba. The patient was treated with polyhexamethylene biguanide and chlorhexidine for 3 months, and recovered with normal visual acuity. Poor hygiene and insufficient disinfection may be major risk factors for Acanthameoba keratitis in cosmetic contact lens wearers. The cosmetic contact lens user should receive professional advice before accessing the lenses, and this must be communicated to the public.

  18. Cosmological applications of strong gravitational lensing

    DEFF Research Database (Denmark)

    Paraficz, Danuta

    by Refsdal (1964), H0, !m and !! can be measured based on the time delay ("t) between multiply lensed images of QSOs, because "t depends on H0 and on the distances to lens and source, hence!m and !!. Determination of cosmological parameters using gravitational lensing suffers from some degeneracies......, but it is based on well understood physics and unlike distance ladder methods there are no calibration issues. Moreover, it has an advantage over some of the leading methods (such as Type Ia SNe) in that it is a purely cosmological approach. In this thesis, the property of strong gravitational lensing - time...... delay - is extensively explored. Strong gravitational lensing, and in particular time delays, are investigated here both theoretically and observationally. The focus is on the time delay as a cosmological and astrophysical tool to constrain H0, !m, !!, and to measure the masses of lensing galaxies...

  19. Medical uses of cosmetic colored contact lenses.

    Science.gov (United States)

    Cole, C J; Vogt, U

    2006-07-01

    To explore the clinical issues surrounding the use of hand-painted contact lenses for medical indications and to assess patient satisfaction with the use of these lenses for an unsightly eye. A questionnaire was sent to all patients visiting the contact lens department of Western Eye Hospital for a colored contact lens fitting during a 1-year period. The questionnaire related to patient satisfaction with the lenses and aspects of wear. Replies were received from 25 of a total of 33 patients. The average wearing time was 11.3 hours per day. Most (88%) patients wore lenses for cosmetic reasons, and 12% wore lenses for cosmetic and refractive purposes. Satisfaction was 76% regarding lens comfort and 88% regarding lens color. Provided lens care is satisfactory and the patient does not have unreasonable expectations, a tinted contact lens can be a useful device. In view of the cost implication, this is a valuable service provided by the hospital.

  20. Developments in Accommodating Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Zeki Tunç

    2012-07-01

    Full Text Available Technical progress in cataract surgery has decreased the incidence of severe complications in this type of surgery. The introduction of micro incision cataract surgery (MICS (sub- 2.0 mm incision allow the surgeon to achieve better postoperative control of astigmatism and higherorder aberration (HOAs with minimum induction of both. It is believed that multifocal lenses provide very successful results, however, there are limitations to these. Implantation of accommodating intraocular lenses (IOLs is an option to treat presbyopia. The IOLs work by using the continued functionality of the ciliary muscle after cataract removal. Accommodating IOLs were designed to avoid the optical side effects of multifocal IOLs. Two main design concepts exist. First, axial shift concepts rely on anterior axial movement of one or two optics creating accommodative ability. Second, curvature change designs are designed to provide significant amplitudes of accommodation with little physical displacement. Accommodative IOLs to correct astigmatism and HOAs in the future are needed. (Turk J Ophthalmol 2012; 42: 288-93

  1. Using Time Separation of Signals to Obtain Independent Proton and Antiproton Beam Position Measurements Around the Tevatron

    CERN Document Server

    Webber, Robert C

    2005-01-01

    Independent position measurement of the counter-circulating proton and antiproton beams in the Tevatron presents a challenge to upgrading the Tevatron Beam Position Monitor (BPM) system. The inherent directionality of the Tevatron BPM pickup design provides 26dB isolation between signals from the two beams. At the present typical 10:1 proton-to-antiproton bunch intensity ratio, this isolation alone is insufficient to support millimeter accuracy antiproton beam position measurements due to interfering proton signals. An accurate and manageable solution to the interfering signal problem is required for antiproton measurements now and, as machine improvements lead to increased antiproton intensity, will facilitate future elimination of antiproton bias on proton beam position measurements. This paper discusses the possibilities and complications of using time separation of the two beam signals at the numerous Tevatron BPM locations and given the dynamic longitudinal conditions of Tevatron operation. Results of me...

  2. Planck 2015 results. XV. Gravitational lensing

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; White, M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2016-09-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40σ), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator, we detect lensing at a significance of 5σ. We cross-check the accuracy of our measurement using the wide frequency coverage and complementarity of the temperature and polarization measurements. Public products based on this measurement include an estimate of the lensing potential over approximately 70% of the sky, an estimate of the lensing potential power spectrum in bandpowers for the multipole range 40 ≤ L ≤ 400, and an associated likelihood for cosmological parameter constraints. We find good agreement between our measurement of the lensing potential power spectrum and that found in the ΛCDM model that best fits the Planck temperature and polarization power spectra. Using the lensing likelihood alone we obtain a percent-level measurement of the parameter combination σ8Ω0.25m = 0.591 ± 0.021. We combine our determination of the lensing potential with the E-mode polarization, also measured by Planck, to generate an estimate of the lensing B-mode. We show that this lensing B-mode estimate is correlated with the B-modes observed directly by Planck at the expected level and with a statistical significance of 10σ, confirming Planck's sensitivity to this known sky signal. We also correlate our lensing potential estimate with the large-scale temperature anisotropies, detecting a cross-correlation at the 3σ level, as expected because of dark energy in the concordance ΛCDM model.

  3. Contact lenses to slow progression of myopia.

    Science.gov (United States)

    Sankaridurg, Padmaja

    2017-09-01

    The prevalence of myopia has been steadily rising, with 28 per cent of the global population said to be affected in 2010 and to rise to affect nearly 50 per cent by 2050. Increasing levels of myopia increase the risk of vision impairment and in particular, high myopia is associated with the risk of serious and permanent visual disability due to associated sight-threatening complications. To stem the burden associated with higher levels of myopia, there are efforts to slow the progression of myopia, and several optical and pharmaceutical strategies have been found useful in slowing myopia to varying degrees. More recently, numerous multifocal soft contact lenses and extended depth of focus soft contact lenses (collectively referred to as myopia control contact lenses) were found effective in slowing myopia. As opposed to overnight orthokeratology, myopia control contact lenses are worn during the day and the hypotheses proposed to explain the efficacy of these lenses are generally based on the premise that the stimulus for eye growth is a defocused retinal image with hyperopic blur either centrally or peripherally. Although the individual power profiles of the lenses vary, the contact lens generally incorporates 'positive power' to reduce the hyperopic blur and/or impose myopic defocus or in the case of the extended depth of focus lens, has a power profile designed to optimise retinal image quality for points on or in front of the retina. The use of soft contact lenses as a platform for myopia control offers an exciting and effective avenue to manage myopia but there is a need for further research on issues such as the mechanism underlying control of myopia, improving efficacy with lenses, and understanding rebound on discontinuation. More significantly, although contact lenses are generally safe and improve quality of life in older children, one of the major challenges for improved uptake and acceptance of contact lenses centres on the perceived risk of

  4. Bacterial and fungal biofilm formation on contact lenses and their susceptibility to lens care solutions.

    Science.gov (United States)

    Kackar, Siddharth; Suman, Ethel; Kotian, M Shashidhar

    2017-01-01

    Microbial biofilm formation on contact lenses and lens storage cases may be a risk factor for contact lens-associated corneal infections. Various types of contact lens care solutions are used to reduce microbial growths on lenses. The present study aimed at comparing the growths of biofilms on the different contact lenses and lens cases. The study also aimed at determining the effect of lens care solutions and bacteriophage on these biofilms. One type of hard lens and two types of soft lenses were used for the study. The organisms used were Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 60193 and Escherichia coli ATCC 25922. Biofilm production was performed by modified O'Toole and Kolter method and effect of lens cleaning solutions and a crude coliphage on biofilms was also studied. Results were visualised using scanning electron microscopy and quantitated by colony counting method and spectrophotometric measurement of optical density (OD). Statistical analysis was done by SPSS 11.5, Kruskal-Wallis test and Chi-square test. Soft lens cleaning solutions had a significant inhibitory effect (P = 0.020) on biofilm formation on soft lenses and also lens cases (P contact lenses.

  5. lenses

    African Journals Online (AJOL)

    The prevalence of iron deficiency is reported to affect up to 50% of both women of childbearing age and infants.13 Before implementation of iron-fortified foods by national governments, iron supplementation was used as strategy to combat iron deficiency.14 In the South. African fortification programme, electrolytic iron was.

  6. [Ultrastructural changes in various cataractous lenses in rats].

    Science.gov (United States)

    Li, G; Chen, C

    1996-03-01

    To study the ultrastructural changes of lenses aged 50 days from normal rats and rats with three kinds of cataract. Transmission electron microscope (TEM) was used to investigate the ultrastructural changes of normal lens, selenium, galactosemic and congenital cataracts in the rat. In the normal group, the structure of cell membrane in cortex is not changed obviously, but in the lens nucleus there are slight cellular degeneration, low cytoplasmic density and the destruction of intercellular junctional complexes. In the selenium cataratous lens, in the lens cortex and nucleus the cellular junctional complexes are damaged severely, the cystic degeneration of mitochondria in the cytoplasm is obvious, the cytoplasmic density becomes lower and slight liquefaction can be observed in some parts of cytoplasm. In the galactosemic cataractous lens, in the cortex obvious liquefaction, vesicles and globular structures can be found within the cytoplasm, intercellular spaces are enlarged and liquified markedly, and in the lens nuclear area the cytoplasm appears as fine sands. In congenital cataractous lens, the cellular structure in cortex is essentially normal, but there are marked destruction of junctional complexes, obvious cystic degeneration of mitochondria and cytoplasmic aggregation with uneven distribution in the lens nuclear area. The ultrastructural changes in different kinds of cataractous lenses depend on the extent and location of opacification in lenses.

  7. Large Scale Cleaning Telescope Mirrors with Electron Beams Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Cleaning Lenses and Mirrored Surfaces with Electrons tasks include: Development of Fractal Wand Geometries; Vacuum Chamber testing for Fractal Wand Prototypes;...

  8. Investigations of Galaxy Clusters Using Gravitational Lensing

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Matthew P. [Northern Illinois Univ., DeKalb, IL (United States)

    2014-08-01

    In this dissertation, we discuss the properties of galaxy clusters that have been determined using strong and weak gravitational lensing. A galaxy cluster is a collection of galaxies that are bound together by the force of gravity, while gravitational lensing is the bending of light by gravity. Strong lensing is the formation of arcs or rings of light surrounding clusters and weak lensing is a change in the apparent shapes of many galaxies. In this work we examine the properties of several samples of galaxy clusters using gravitational lensing. In Chapter 1 we introduce astrophysical theory of galaxy clusters and gravitational lensing. In Chapter 2 we examine evidence from our data that galaxy clusters are more concentrated than cosmology would predict. In Chapter 3 we investigate whether our assumptions about the number of galaxies in our clusters was valid by examining new data. In Chapter 4 we describe a determination of a relationship between mass and number of galaxies in a cluster at higher redshift than has been found before. In Chapter 5 we describe a model of the mass distribution in one of the ten lensing systems discovered by our group at Fermilab. Finally in Chapter 6 we summarize our conclusions.

  9. Contrast visual acuity with bifocal contact lenses.

    Science.gov (United States)

    Ueda, Kiichi; Inagaki, Yasuko

    2007-03-01

    To compare the quality of vision of a bifocal rigid gas-permeable contact lens versus a bifocal soft contact lens in subjects with presbyopia. Sixteen healthy presbyopic subjects with no ocular disease but experienced with contact lens wear were enrolled in the study. Subjects randomly wore both types of bifocal lenses for 30 minutes with a washout period of 30 minutes each in a crossover manner. The primary outcome measure was the difference in contrast visual acuity. Distance and near contrast visual acuities with the two bifocal lens types were measured in different lighting environments and at multiple contrast levels. After the measurement, subjects were asked to rate their subjective vision by using the four categories with both lens types throughout the study. At the end of the study, subjects were also asked which of the two lens types they preferred. Under photopic conditions, distance and near visual acuities decreased at the 25% and 10% contrast levels, respectively, in subjects wearing bifocal soft contact lenses (Pcontact lenses (P0.05), but bifocal rigid gas-permeable lenses were clearer than bifocal soft contact lenses for near vision (Pcontact lenses showed better visual performance than bifocal soft contact lenses did.

  10. Observation and studies of double J/psi production at the Tevatron

    Czech Academy of Sciences Publication Activity Database

    Abazov, V. M.; Abbott, B.; Acharya, B.S.; Kupčo, Alexander; Lokajíček, Miloš

    2014-01-01

    Roč. 90, č. 11 (2014), "111101-1"-"111101-8" ISSN 1550-7998 R&D Projects: GA MŠk(CZ) LG12006 Institutional support: RVO:68378271 Keywords : Batavia TEVATRON Coll * parton * density * nucleon * model * anti-p p * inclusive reaction Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 4.643, year: 2014

  11. Combination of measurements of the top-quark pair production cross section from the Tevatron Collider

    Czech Academy of Sciences Publication Activity Database

    Aaltonen, T.; Abazov, V. M.; Abbott, B.; Kupčo, Alexander; Lokajíček, Miloš; Lysák, Roman

    2014-01-01

    Roč. 89, č. 7 (2014), "072001-1"-"072001-16" ISSN 1550-7998 R&D Projects: GA MŠk(CZ) LG12006 Institutional support: RVO:68378271 Keywords : Batavia TEVATRON Coll * quantum chromodynamics * perturbation theory * statistical analysis * CDF * DZERO Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 4.643, year: 2014

  12. B_s oscillation and prospects for delta m_s at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Menzemer, Stephanie; /MIT

    2005-07-01

    Till the start of the LHC, the Tevatron is the only running accelerator which produces enough B{sub s} mesons to perform {Delta}m{sub s} measurements. The status--as it was at the time of the conference--of two different {Delta}m{sub s} analysis performed both by the CDF and D0 collaboration will be presented.

  13. Search for fourth generation quarks and leptons at the Fermilab Tevatron and CERN Large Hadron Collider

    CERN Document Server

    Ginzburg, I F; Schiller, A

    1999-01-01

    If the next generations of heavy quarks and leptons exist within the standard model (SM), they can manifest themselves in Higgs boson production at the Fermilab Tevatron and the CERN LHC, before being actually observed. This generation leads to an increase of the Higgs boson production cross section via gluon fusion at hadron colliders by a factor 6-9. So, the study of this process at the Tevatron and LHC can finally fix the number of generations in the SM. Using the WW* Higgs boson decay channel, the studies at the upgraded Tevatron will answer the question about the next generation for mass values 135 GeV Tevatron, studies in this channel could explore the mass range 110-140 GeV. (15 refs).

  14. Accelerator Science and Technology Breakthroughs, Achievements and Lessons from the Tevatron

    CERN Document Server

    Shiltsev, Vladimir

    2011-01-01

    For almost a quarter of a century, the Tevatron proton-antiproton collider was the centerpiece of the world's high energy physics program - beginning operation in December of 1985 until it was overtaken by LHC in 2011. The aim of this unique scientific instrument was to explore the elementary particle physics reactions with center of mass collision energies of up to 1.96 TeV. The initial design luminosity of the Tevatron was 1030cm-2s-1, however as a result of two decades of upgrades, the accelerator has been able to deliver 430 times higher luminosities to each of two high luminosity experiments, CDF and D0. The Tevatron will be shut off September 30, 2011. The collider was arguably one of the most complex research instruments ever to reach the operation stage and is widely recognized for many technological breakthroughs and numerous physics discoveries. In this John Adams lecture, I briefly present the history of the Tevatron, major advances in accelerator physics, and technology implemented during the long...

  15. Electroweak radiative effects in the single $W$-production at Tevatron and LHC

    OpenAIRE

    Akushevich, I.; Ilyichev, A.; Shumeiko, N.; Zykunov, V.

    2003-01-01

    An alternative calculation of the lowest order electroweak radiative corrections to the single W-boson production in hadron-hadron collision in the framework of the quark parton model without any absorption of the collinear quark singularity into the parton distributions is carried out. Numerical analysis under Tevatron and LHC kinematic conditions is performed.

  16. Nanofocusing refractive X-ray lenses

    Energy Technology Data Exchange (ETDEWEB)

    Boye, Pit

    2010-02-05

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is required. This is achieved in refractive lenses by moving to a compact lens design where several single lenses are stacked behind each other. The, so-called nanofocusing refractive lenses (NFLs) have a parabolic cylindrical shape with lateral structure sizes in the micrometer range. NFLs are produced by using micro-machining techniques. These micro-fabrication processes and technologies are introduced. The results of the optimization and the final fabrication process for silicon lenses are presented. Subsequently, two experiments that are exemplary for the use of NFLs, are introduced. The rst one employs a high-resolution scanning fluorescence mapping of a geological sample, and the second one is a coherent x-ray diffraction imaging (CXDI) experiment. CXDI is able to reconstruct the illuminated object from recorded coherent diffraction patterns. In a scanning mode, referred to as ptychography, this method is even able to reconstruct the illumination and the object simultaneously. Especially the reconstructed illumination and the possibility of computed propagation of the wave field along the

  17. Comparative study of two silicone hydrogel contact lenses used as bandage contact lenses after photorefractive keratectomy

    OpenAIRE

    Hasan Razmjoo; Elham Abdi; Sayna Atashkadi; Reza, Akhlaghi M; Peyman A Reza; Mojtaba Akbari

    2012-01-01

    Background: Silicon hydrogel bandage contact lenses are used to enhance epithelial healing, control surface-generated pain, and prevent epithelial erosions after refractive surgery. Considering the importance of faster reepithelialization in preventing complications of photorefractive keratectomy (PRK) and the fact that the features and specifications of these commercially-available lenses are different and their performance as a postoperative bandage lenses would be different also, the aim o...

  18. Comparative Study of Two Silicone Hydrogel Contact Lenses used as Bandage Contact Lenses after Photorefractive Keratectomy

    OpenAIRE

    Razmjoo, Hasan; Abdi, Elham; Atashkadi, Sayna; Reza, Akhlaghi M; Peyman A Reza; Akbari, Mojtaba

    2012-01-01

    Background: Silicon hydrogel bandage contact lenses are used to enhance epithelial healing, control surface-generated pain, and prevent epithelial erosions after refractive surgery. Considering the importance of faster reepithelialization in preventing complications of photorefractive keratectomy (PRK) and the fact that the features and specifications of these commercially-available lenses are different and their performance as a postoperative bandage lenses would be different also, the aim o...

  19. Search for WH Associated Production in the l upsilon b-bbar Final State Using the DØ Detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Jonathan [Paris Diderot Univ. (France)

    2011-09-15

    The Standard Model is the framework which allows to describe interactions between particles and their dynamics. The Higgs mechanism is a solution to naturally introduce a mass term in the theoretical description of this model. After electroweak spontaneous symmetry breaking, a new massive scalar particle is introduced, the Higgs boson. Since it hasn’t been discovered yet, the search for the Higgs boson is carried at the Tevatron, which is a p$\\bar{p}$ collider at a center-of-mass of 1.96 TeV. For MH <115 GeV, the dominant decay mode is H → b$\\bar{b}$ . The analysis presented in this document is focused on the 100< MH <150 GeV mass range, in the channel where the Higgs boson is produced in assocation with a W boson which decays either to an electron or muon and a neutrino. The study of this final state relies on informations collected from all parts of the DØ detector. A result based on 5.3 fb-1 of RunII Tevatron collisions is presented here. In order to increase the sensitivity to the signal, the analysis is separated in different sub-channels according to the lepton flavour, number of jets in the final state, number of jets identified as originated from b quarks and data taking periods. After selecting events, a multivariate analysis technique is used to separate signal-like events from the expected physics and instrumental backgrounds. A good agreement between data and simulation is observed. As no signal excess is observed in data, an observed (expected) upper limit of 4.5 (4.8) for MH = 115 GeV is set on the ratio of the WH cross section multiplied by the H → b$\\bar{b}$ branching fraction to its standard model prediction, at 95% confidence level. Since the final Tevatron dataset is soon to be analyzed, an effort is brought to achieve the maximum sensitivity. A preliminary analysis updated in Summer 2011 is presented as well as future improvements to be considered in the final publication for the search in

  20. Characterisation of adaptive fluidic silicone membrane lenses

    CSIR Research Space (South Africa)

    Schneider, F

    2009-09-01

    Full Text Available In this paper the auhtors compare the performance and optical quality of two types of adaptive fluidic silicone-membrane lenses. The membranes feature either a homogeneous thickness, or they are shaped resulting in an inhomogeneous cross...

  1. Weak Gravitational Lensing of Finite Beams

    Science.gov (United States)

    Fleury, Pierre; Larena, Julien; Uzan, Jean-Philippe

    2017-11-01

    The standard theory of weak gravitational lensing relies on the infinitesimal light beam approximation. In this context, images are distorted by convergence and shear, the respective sources of which unphysically depend on the resolution of the distribution of matter—the so-called Ricci-Weyl problem. In this Letter, we propose a strong-lensing-inspired formalism to describe the lensing of finite beams. We address the Ricci-Weyl problem by showing explicitly that convergence is caused by the matter enclosed by the beam, regardless of its distribution. Furthermore, shear turns out to be systematically enhanced by the finiteness of the beam. This implies, in particular, that the Kaiser-Squires relation between shear and convergence is violated, which could have profound consequences on the interpretation of weak-lensing surveys.

  2. Disposable contact lenses in penetrating keratoplasty.

    Science.gov (United States)

    Arora, R; Gupta, S; Taneja, M; Raina, U K; Mehta, D K

    2000-07-01

    To evaluate the therapeutic efficacy of disposable contact lenses in management of complications after keratoplasty. Twenty-eight patients with various post keratoplasty complications were fit with disposable contact lenses (45% Vifilcon A and 55% water content). Indications for lens use included persistent epithelial defects, wound leak, graft edema, dry eye and protection of normal corneal epithelium. Success was obtained with the therapeutic use of disposable lenses in 20 of the 28 cases. The best results were seen in maintenance and restoration of healthy ocular surface and small wound leaks. Stromal graft edema with no epithelial involvement was the major area of therapeutic failure. Disposable contact lenses are an attractive low cost option in the management of complications after keratoplasty. They are particularly useful in maintaining a healthy ocular surface, providing symptomatic relief and avoiding resurgery in patients with small wound leaks.

  3. Terrestrial freshwater lenses: Unexplored subterranean oases

    Science.gov (United States)

    Laattoe, Tariq; Werner, Adrian D.; Woods, Juliette A.; Cartwright, Ian

    2017-10-01

    Freshwater lenses are lenticular bodies of fresh (TDS lenses in coastal aquifers, the formation, location and persistence of freshwater lenses in terrestrial settings are poorly understood. This is despite inland aquifers commonly containing saline groundwater, particularly in arid and semi-arid climates, and the local occurrences of freshwater being critical for ecosystems and human endeavour. We identify and classify known terrestrial freshwater lenses (TFLs) using four formation categories, namely topography, geology, groundwater-surface water interaction and recharge mechanisms. The resulting typology highlights the importance of buoyancy in the formation of TFLs in otherwise unlikely situations, implying that TFLs may be more prevalent than previously thought. TFLs represent some of the most vulnerable and precious freshwater resources on Earth that require considerably more research into mechanisms of formation and threats to their existence.

  4. Raman imaging of layered soft contact lenses.

    Science.gov (United States)

    Krysztofiak, Katarzyna; Ciężar, Kamila; Kościński, Mikołaj

    2017-04-26

    Daily disposable contact lenses are gaining in popularity among practitioners and wearers for the improved ocular health and subjective outcomes they offer. Recently a novel daily disposable contact lens material with water gradient technology was introduced. Delefilcon A lenses consist of a 33% water content silicone hydrogel core and an outer hydrogel layer which is totally free of silicone and contains 80% water. The aim of the present study was to confirm the layered structure of delefilcon A contact lenses. Thickness of hydrogel coating on the silicone hydrogel core was assessed using Raman spectroscopy. To investigate the layered structure of the material, depth spectra of the lenses were recorded. The results obtained suggest that at about 6 μm a boundary between the hydrogel layer and silicone hydrogel core exists, which is in good agreement with the manufacturer's data. Data collected in this experiment confirm a water gradient at the delefilcon A lens surface.

  5. Gravitational Lensing Mass Mapping with Gaussian Processes

    Science.gov (United States)

    Schneider, Michael; Ng, Karen; Dawson, William; Marshall, Phil; Meyers, Joshua; Bard, Deborah

    2018-01-01

    We infer gravitational lensing shear and convergence fields from galaxy ellipticity catalogs under a Gaussian Process prior for the lensing potential. We demonstrate the performance of our algorithm with simulated Gaussian-distributed cosmological lensing shear maps and a reconstruction of the mass distribution of the merging galaxy cluster Abell 781 using galaxy ellipticities measured with the Deep Lens Survey. Given interim posterior samples of lensing shear or convergence fields on the sky, we describe an algorithm to infer cosmological parameters via lens field marginalization. In the most general formulation of our algorithm we make no assumptions about weak shear orGaussian-distributed shape noise or shears. Because we require solutions and matrix determinants of a linear system of dimension that scales with the number of galaxies, we present computational performance metrics with approximate algorithms that introduce sparsity in the Gaussian Process kernel.

  6. Microbial adherence to cosmetic contact lenses.

    Science.gov (United States)

    Chan, Ka Yin; Cho, Pauline; Boost, Maureen

    2014-08-01

    To investigate whether cosmetic contact lenses (CCL) with surface pigments affect microbial adherence. Fifteen brands of CCL were purchased from optical, non-optical retail outlets, and via the Internet. A standardized rub-off test was performed on each CCL (five lenses per brand) to confirm the location of the pigments. The rub-off test comprised gentle rubbing on the surfaces of each CCL with wetted cotton buds for a maximum of 20 rubs per surface. A new set of CCL (five lenses per brand) were incubated in Pseudomonas aeruginosa overnight. Viable counts of adhered bacteria were determined by the number of colony-forming units (CFU) on agar media on each lens. The adherence of P. aeruginosa as well as Staphylococcus aureus and Serratia marcescens to three brands of CCL (A-C) (five lenses per brand) were also compared to their adherences on their clear counterparts. Only two of the 15 brands of CCL tested (brands B and C) had pigments that did not detach with the rub-off test. The remaining 13 brands of CCL all failed the rub-off test and these lenses showed higher P. aeruginosa adherence (8.7 × 10(5)-1.9 × 10(6) CFU/lens). Brands B and C lenses showed at least six times less bacterial adhesion than the other 13 brands. Compared to their clear counterparts, bacterial adherence to brands B and C lenses did not differ significantly, whereas brand A lenses showed significantly higher adherence. Surface pigments on CCL resulted in significantly higher bacterial adherence. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  7. Measurement of cross section of quark pair production top with the D0 experiment at the Tevatron and determination the top quark mass using this measure

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier-Thery, Solene [Univ. Pierre et Marie Curie, Paris (France)

    2010-06-01

    The top quark has been discovered by CDF and D0 experiments in 1995 at the proton-antiproton collider Tevatron. The amount of data recorded by both experiments makes it possible to accurately study the properties of this quark: its mass is now known to better than 1% accuracy. This thesis describes the measurement of the top pair cross section in the electron muon channel with 4, 3 fb -1 recorded data between 2006 and 2009 by the D0 experiment. Since the final state included a muon, improvements of some aspects of its identification have been performed : a study of the contamination of the cosmic muons and a study of the quality of the muon tracks. The cross section measurement is in good agreement with the theoretical calculations and the other experimental measurements. This measurement has been used to extract a value for the top quark mass. This method allows for the extraction of a better defined top mass than direct measurements as it depends less on Monte Carlo simulations. The uncertainty on this extracted mass, dominated by the experimental one, is however larger than for direct measurements. In order to decrease this uncertainty, the ratio of the Z boson and the top pair production cross sections has been studied to look for some possible theoretical correlations. At the Tevatron, the two cross sections are not theoretically correlated: no decrease of the uncertainty on the extracted top mass is therefore possible.

  8. Factors influencing bacterial adhesion to contact lenses

    Science.gov (United States)

    Dutta, Debarun; Willcox, Mark

    2012-01-01

    The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria. PMID:22259220

  9. Maximum a posteriori CMB lensing reconstruction

    Science.gov (United States)

    Carron, Julien; Lewis, Antony

    2017-09-01

    Gravitational lensing of the cosmic microwave background (CMB) is a valuable cosmological signal that correlates to tracers of large-scale structure and acts as a important source of confusion for primordial B -mode polarization. State-of-the-art lensing reconstruction analyses use quadratic estimators, which are easily applicable to data. However, these estimators are known to be suboptimal, in particular for polarization, and large improvements are expected to be possible for high signal-to-noise polarization experiments. We develop a method and numerical code, lensit, that is able to find efficiently the most probable lensing map, introducing no significant approximations to the lensed CMB likelihood, and applicable to beamed and masked data with inhomogeneous noise. It works by iteratively reconstructing the primordial unlensed CMB using a deflection estimate and its inverse, and removing residual lensing from these maps with quadratic estimator techniques. Roughly linear computational cost is maintained due to fast convergence of iterative searches, combined with the local nature of lensing. The method achieves the maximal improvement in signal to noise expected from analytical considerations on the unmasked parts of the sky. Delensing with this optimal map leads to forecast tensor-to-scalar ratio parameter errors improved by a factor ≃2 compared to the quadratic estimator in a CMB stage IV configuration.

  10. Disability glare in soft multifocal contact lenses.

    Science.gov (United States)

    Wahl, Siegfried; Fornoff, Luise; Ochakovski, G Alex; Ohlendorf, Arne

    2017-10-07

    The study investigated the effect of the design of multifocal contact lenses on the sensitivity to contrast and disability glare. Contrast sensitivity was measured in 16 young adults (mean age: 25.5±2.5years) at a distance of 2m under two conditions: no-glare and glare. Two designs (Center Near and Center Distance) of the Biofinity soft contact lens were used to simulate correction for presbyopes, while a correction with single vision trial lenses and contact lenses acted as controls. The design of the used multifocal contact lenses had a significant influence on the log area under the curve of the contrast sensitivity function (AUC-CSF). Compared to the spectacle lens correction, the AUC-CSF was significantly reduced, in case CS was measured with the Center Near design lens, under the no-glare (pCenter Distance design contact lens, the AUC-CSF was significantly smaller in case CS was tested under glare (p=0.001). Disability glare (DG) was depending on the spatial frequency and the design of the multifocal lens, while the Center Distance design produced higher amounts of DG (pcontact lenses has a significant impact on the contrast sensitivity as well as the disability glare. In order to dispense the best correction in terms of contact lenses, the sensitivity to contrast under no-glare and glare conditions should be tested a medium spatial frequencies. Copyright © 2017. Published by Elsevier Ltd.

  11. Factors influencing bacterial adhesion to contact lenses.

    Science.gov (United States)

    Dutta, Debarun; Cole, Nerida; Willcox, Mark

    2012-01-01

    The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria.

  12. Cosmological test using strong gravitational lensing systems

    Science.gov (United States)

    Yuan, C. C.; Wang, F. Y.

    2015-09-01

    As one of the probes of universe, strong gravitational lensing systems allow us to compare different cosmological models and constrain vital cosmological parameters. This purpose can be reached from the dynamic and geometry properties of strong gravitational lensing systems, for instance, time-delay Δτ of images, the velocity dispersion σ of the lensing galaxies and the combination of these two effects, Δτ/σ2. In this paper, in order to carry out one-on-one comparisons between ΛCDM universe and Rh = ct universe, we use a sample containing 36 strong lensing systems with the measurement of velocity dispersion from the Sloan Lens Advanced Camera for Surveys (SLACS) and Lens Structure and Dynamic survey (LSD) survey. Concerning the time-delay effect, 12 two-image lensing systems with Δτ are also used. In addition, Monte Carlo simulations are used to compare the efficiency of the three methods as mentioned above. From simulations, we estimate the number of lenses required to rule out one model at the 99.7 per cent confidence level. Comparing with constraints from Δτ and the velocity dispersion σ, we find that using Δτ/σ2 can improve the discrimination between cosmological models. Despite the independence tests of these methods reveal a correlation between Δτ/σ2 and σ, Δτ/σ2 could be considered as an improved method of σ if more data samples are available.

  13. Transport of intense proton beams in an induction linac by solenoid lenses

    Science.gov (United States)

    Namkung, W.; Choe, J. Y.; Uhm, H. S.

    1986-01-01

    In the proposed proton induction linac at NSWC, a 100 A and 3 μs proton beam is accelerated to 5 MeV through a series of accelerating gaps. This beam can be effectively focused by solenoid lenses in this low energy regime and can be transported by adjusting the focusing strength in each period. For the transport channel design to reduce the number of independently controlled lenses, a theory of matched beams in the space-charge dominated regime has been developed. This study can be applied to cost efficient designs of induction accelerators for heavy ion fusion and free electron lasers.

  14. Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation)

    Energy Technology Data Exchange (ETDEWEB)

    Massey, Richard [Durham Univ., Durham (United Kingdom); Hoekstra, Henk [Leiden Univ., Leiden (Netherlands); Kitching, Thomas [Univ. of Edinburg, Edinburg (United Kingdom); Rhodes, Jason [California Institute of Technology, Pasadena, CA (United States); Cropper, Mark [Univ. College London, Surrey (United Kingdom); Amiaux, Jerome [CEA Saclay, Gif sur Yvette (France); Harvey, David [Univ. of Edinburg, Edinburg (United Kingdom); Mellier, Yannick [Univ. Pierre et Marie Curie, Paris (France); CEA Saclay, Gif sur Yvette (France); Meneghetti, Massimo [Istituto Nazionale di Astrofisica (INAF), Bologna (Italy); Miller, Lance [Univ. of Oxford, Oxford (United Kingdom); Paulin-Henriksson, Stephane [CEA Saclay, Gif sur Yvette (France); Pires, Sandrine [CEA Saclay, Gif sur Yvette (France); Scaramella, Roberto [Istituto Nazionale di Astrofisica (INAF), Monteporzio Catone (Italy); Schrabback, Tim [Stanford Univ., Stanford, CA (United States); Argelander-Institut fur Astronomie, Bonn (Germany)

    2012-12-13

    The first half of this paper explores the origin of systematic biases in the measurement of weak gravitational lensing. Compared to previous work, we expand the investigation of point spread function instability and fold in for the first time the effects of non-idealities in electronic imaging detectors and imperfect galaxy shape measurement algorithms. In addition, these now explain the additive A(ℓ) and multiplicative M(ℓ) systematics typically reported in current lensing measurements. We find that overall performance is driven by a product of a telescope/camera's absolute performance, and our knowledge about its performance.

  15. Thin lenses of asymmetric power

    Directory of Open Access Journals (Sweden)

    W. F. Harris

    2009-12-01

    Full Text Available It is generally supposed that thin systems, including refracting surfaces and thin lenses, have powers that are necessarily symmetric.  In other words they have powers which can be represented assymmetric dioptric power matrices and in the familar spherocylindrical form used in optometry and ophthalmology.  This paper shows that this is not correct and that it is indeed possible for a thin system to have a power that is not symmetric and which cannot be expressed in spherocylindrical form.  Thin systems of asymmetric power are illustratedby means of a thin lens that is modelled with small prisms and is chosen to have a dioptric power ma-trix that is antisymmetric.  Similar models can be devised for a thin system whose dioptric power matrix is any  2 2 ×  matrix.  Thus any power, symmetric, asymmetric or antisymmetric, is possible for a thin system.  In this sense our understanding of the power of thin systems is now complete.

  16. Implications of direct dark matter constraints for minimal supersymmetric standard model Higgs boson searches at the Tevatron.

    Science.gov (United States)

    Carena, Marcela; Hooper, Dan; Skands, Peter

    2006-08-04

    In regions of large tanbeta and small mAlpha, searches for heavy neutral minimal supersymmetric standard model (MSSM) Higgs bosons at the Tevatron are promising. At the same time, rates in direct dark matter experiments, such as CDMS, are enhanced in the case of large tanbeta and small mAlpha. As a result, there is a natural interplay between the heavy, neutral Higgs searches at the Tevatron and the region of parameter space explored by CDMS. We show that if the lightest neutralino makes up the dark matter of our universe, current limits from CDMS strongly constrain the prospects of heavy, neutral MSSM Higgs discovery at the Tevatron unless |mu| greater or approximately 400 GeV. The limits of CDMS projected for 2007 will increase this constraint to |mu| greater or approximately 800 GeV. If CDMS does observe neutralinos in the near future, however, it will make the discovery of Higgs bosons at the Tevatron far more likely.

  17. An End of Service Life Assessment of PMMA Lenses from Veteran Concentrator Photovoltaic Systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Khonkar, Hussameldin I.; Herrero, Rebecca; Anton, Ignacio; Johnson, David K.; Vinzant, Todd B.; Deutch, Steve; To, Bobby; Sala, Gabriel; Kurtz, Sarah R.

    2017-03-21

    The optical performance of poly(methyl methacrylate) lenses from veteran concentrator photovoltaic modules was examined after the end of their service life. Lenses from the Martin-Marietta and Intersol module designs were examined from the 'Solar Village' site near Riyadh, Saudi Arabia, as well as the Phoenix Sky Harbor airport, followed by the Arizona Public Service Solar Test and Research (APS-STaR) center in Tempe, Arizona. The various lens specimens were deployed for 20, 27, and 22 years, respectively. Optical characterizations included lens efficiency (Solar Simulator instrument), material transmittance and haze (of coupons cut from veteran lenses, then measured again after their faceted back surface was polished, and then measured again after the incident front surface was polished), and direct transmittance (as a function of detector's acceptance angle, using the Very Low Angular Beam Spread ('VLABS') instrument). Lens efficiency measurements compared the central region to the entire lens, also using hot and cold mirror measurements to diagnose differences in performance. A series of subsequent characterizations was performed because a decrease in performance of greater than 10% was observed for some of the veteran lenses. Surface roughness was examined using atomic force microscopy and scanning electron microscopy. Facet geometry (tip and valley radius) was quantified on cross-sectioned specimens. Molecular weight was compared between the incident and faceted surfaces of the lenses.

  18. Forward-Backward Asymmetry of Top Quark Pair Productionn at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Ziqing [Texas A & M Univ., College Station, TX (United States)

    2015-12-01

    This dissertation presents the final measurements of the forward-backward asymmetry (AFB) of top quark-antiquark pair events (t t-) at the Collider Detector at Fermilab (CDF) experiment. The t t- events are produced in proton{anti-proton collisions with a center of mass energy of 1:96 TeV during the Run II of the Fermilab Tevatron. The measurements are performed with the full CDF Run II data (9.1 fb-1) in the final state that contain two charged leptons (electrons or muons, the dilepton final state), and are designed to con rm or deny the evidence-level excess in the AFB measurements in the final state with a single lepton and hadronic jets (lepton+jets final state) as well as the excess in the preliminary measurements in the dilepton final state with the first half of the CDF Run II data. New measurements include the leptonic AFB (AlFB), the lepton-pair AFB (All FB) and the reconstructed top AFB (At t FB). Each are combined with the previous results from the lepton+jets final state measured at the CDF experiment. The inclusive Al FB, All FB, and At t FB measured in the dilepton final state are 0.072 ± 0.060, 0.076 ± 0.081, and 0.12 ± 0.13, to be compared with the Standard Model (SM) predictions of 0.038 ± 0.003, 0.048 ± 0.004, and 0.010 ± 0.006, respectively. The CDF combination of AlFB and At t FB are 0.090+0:028 -0.026, and 0.160 ± 0.045, respectively. The overall results are consistent with the SM predictions.

  19. Role of silicon contamination on calcification of hydrophilic acrylic intraocular lenses.

    Science.gov (United States)

    Werner, Liliana; Hunter, Brian; Stevens, Scott; Chew, Jesse J L; Mamalis, Nick

    2006-01-01

    To verify the presence of the element silicon on hydrophilic acrylic intraocular lenses (IOLs) explanted because of calcification. Interventional case series with clinicopathological correlation. Twenty explanted IOLs with surface deposits (MemoryLens), and 20 with deposits mostly within their optic substance (SC60B-OUV and Aqua-Sense; 10 each) were used. After gross, microscopic, and histochemical analyses to confirm the presence of deposits, the lenses underwent scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS) for elemental composition, on the external surface of MemoryLens IOLs, and on the surface and internal substance of SC60B-OUV and Aqua-Sense IOLs. The weight percentage of the element silicon was obtained at the level of deposits, and at adjacent deposit-free areas in all lenses. Scanning electron microscopy (SEM) coupled with EDS confirmed that the composition of the deposits was calcium/phosphate in all cases. The element silicon was found in all 40 lenses, on all areas analyzed. The silicon weight percentage was higher at the level of the deposits. The presence of aluminum on five MemoryLens IOLs, and in most of the SC60B-OUV and Aqua-Sense lenses might be related to scattering from the aluminum mounting stubs used for surface analyses. Silicone compounds have been implicated in the calcification of another hydrophilic acrylic design (Hydroview). They may also have a role in the calcification of other hydrophilic acrylic IOLs. Further investigation on the relationship between the presence of the element silicon and the silicone compounds found on calcified hydrophilic acrylic lenses is necessary.

  20. Studies of top quark properties and search for electroweak single top quark production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Mousumi; /Fermilab

    2007-10-01

    The top quark was discovered in 1995 by the CDF and D0 experiments at the Fermilab Tevatron during the Run I operation. Since the start of the Tevatron Run II in 2001, both experiments have collected {approx}2 fb{sup -1} data samples, which are over twenty times larger than that used in the Run 1 discovery. This larger data sample allows more precise studies of top-quark properties; differences between observed top-quark properties and the Standard Model (SM) prediction may give hints to possible physics beyond the SM. Here we present the latest results on the measurements of top-quark properties and the search for electroweak (EW) single top quark production from the CDF and D0 collaborations. The integrated luminosity used for the measurements corresponds to about 1 fb{sup -1}.

  1. Search for Resonant Second Generation Slepton Production at the Fermilab Tevatron

    Science.gov (United States)

    Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Andeen, T.; Anderson, S.; Andrieu, B.; Anzelc, M. S.; Arnoud, Y.; Arov, M.; Askew, A.; Åsman, B.; Jesus, A. C. S. Assis; Atramentov, O.; Autermann, C.; Avila, C.; Ay, C.; Badaud, F.; Baden, A.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, P.; Banerjee, S.; Barberis, E.; Bargassa, P.; Baringer, P.; Barnes, C.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Bellavance, A.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Berntzon, L.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Binder, M.; Biscarat, C.; Black, K. M.; Blackler, I.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Bloom, K.; Blumenschein, U.; Boehnlein, A.; Boeriu, O.; Bolton, T. A.; Borcherding, F.; Borissov, G.; Bos, K.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Busato, E.; Buszello, C. P.; Butler, J. M.; Calfayan, P.; Calvet, S.; Cammin, J.; Caron, S.; Carvalho, W.; Casey, B. C. K.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapin, D.; Charles, F.; Cheu, E.; Chevallier, F.; Cho, D. K.; Choi, S.; Choudhary, B.; Christofek, L.; Claes, D.; Clément, B.; Clément, C.; Coadou, Y.; Cooke, M.; Cooper, W. E.; Coppage, D.; Corcoran, M.; Cousinou, M.-C.; Cox, B.; Crépé-Renaudin, S.; Cutts, D.; Ćwiok, M.; da Motta, H.; Das, A.; Das, M.; Davies, B.; Davies, G.; Davis, G. A.; de, K.; de Jong, P.; de Jong, S. J.; de La Cruz-Burelo, E.; de Oliveira Martins, C.; Degenhardt, J. D.; Déliot, F.; Demarteau, M.; Demina, R.; Demine, P.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Doidge, M.; Dominguez, A.; Dong, H.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duperrin, A.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Edwards, T.; Ellison, J.; Elmsheuser, J.; Elvira, V. D.; Eno, S.; Ermolov, P.; Estrada, J.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Fatakia, S. N.; Feligioni, L.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fleck, I.; Ford, M.; Fortner, M.; Fox, H.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Garcia, C.; Garcia-Bellido, A.; Gardner, J.; Gavrilov, V.; Gay, A.; Gay, P.; Gelé, D.; Gelhaus, R.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Gollub, N.; Gómez, B.; Gounder, K.; Goussiou, A.; Grannis, P. D.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grünendahl, S.; Grünewald, M. W.; Guo, F.; Guo, J.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hadley, N. J.; Haefner, P.; Hagopian, S.; Haley, J.; Hall, I.; Hall, R. E.; Han, L.; Hanagaki, K.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegeman, J. G.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hoeth, H.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Houben, P.; Hu, Y.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jakobs, K.; Jarvis, C.; Jenkins, A.; Jesik, R.; Johns, K.; Johnson, C.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Juste, A.; Käfer, D.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Kalk, J. M.; Kalk, J. R.; Kappler, S.; Karmanov, D.; Kasper, J.; Kasper, P.; Katsanos, I.; Kau, D.; Kaur, R.; Kehoe, R.; Kermiche, S.; Kesisoglou, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. M.; Khatidze, D.; Kim, H.; Kim, T. J.; Kirby, M. H.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kopal, M.; Korablev, V. M.; Kotcher, J.; Kothari, B.; Koubarovsky, A.; Kozelov, A. V.; Kozminski, J.; Kryemadhi, A.; Krzywdzinski, S.; Kuhl, T.; Kumar, A.; Kunori, S.; Kupco, A.; Kurča, T.; Kvita, J.; Lager, S.; Lammers, S.; Landsberg, G.; Lazoflores, J.; Bihan, A.-C. Le; Lebrun, P.; Lee, W. M.; Leflat, A.; Lehner, F.; Lesne, V.; Leveque, J.; Lewis, P.; Li, J.; Li, Q. Z.; Lima, J. G. R.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Z.; Lobo, L.; Lobodenko, A.; Lokajicek, M.; Lounis, A.; Love, P.; Lubatti, H. J.; Lynker, M.; Lyon, A. L.; Maciel, A. K. A.; Madaras, R. J.; Mättig, P.; Magass, C.; Magerkurth, A.; Magnan, A.-M.; Makovec, N.; Mal, P. K.; Malbouisson, H. B.; Malik, S.; Malyshev, V. L.; Mao, H. S.; Maravin, Y.; Martens, M.; Mattingly, S. E. K.; McCarthy, R.; McCroskey, R.; Meder, D.; Melnitchouk, A.; Mendes, A.; Mendoza, L.; Merkin, M.; Merritt, K. W.

    2006-09-01

    We present a search for supersymmetry in the R-parity violating resonant production and decay of smuons and muon sneutrinos in the channels μ˜→χ˜10μ, μ˜→χ˜2,3,40μ, and ν˜μ→χ˜1,2±μ. We analyzed 0.38fb-1 of integrated luminosity collected between April 2002 and August 2004 with the D0 detector at the Fermilab Tevatron Collider. The observed number of events is in agreement with the standard model expectation, and we calculate 95% C.L. limits on the slepton production cross section times branching fraction to gaugino plus muon, as a function of slepton and gaugino masses. In the framework of minimal supergravity, we set limits on the coupling parameter λ211', extending significantly previous results obtained in Run I of the Tevatron and at the CERN LEP collider.

  2. Search for resonant second generation slepton production at the Fermilab Tevatron.

    Science.gov (United States)

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Askew, A; Asman, B; Jesus, A C S Assis; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cousinou, M-C; Cox, B; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Estrada, J; Evans, H; Evdokimov, A; Evdokimov, V N; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jenkins, A; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Kesisoglou, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Krzywdzinski, S; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lager, S; Lammers, S; Landsberg, G; Lazoflores, J; Bihan, A-C Le; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; McCarthy, R; McCroskey, R; Meder, D; Melnitchouk, A; Mendes, A; Mendoza, L; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Millet, T; Mitrevski, J; Molina, J; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; O'dell, V; O'neil, D C; Obrant, G; Oguri, V; Oliveira, N; Oshima, N; Otec, R; Y Garzón, G J Otero; Owen, M; Padley, P; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Perez, E; Peters, K; Pétroff, P; Petteni, M; Piegaia, R; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Pompos, A; Pope, B G; Popov, A V; da Silva, W L Prado; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rani, K J; Ranjan, K; Rapidis, P A; Ratoff, P N; Renkel, P; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Rud, V I; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sengupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shephard, W D; Shivpuri, R K; Shpakov, D; Siccardi, V; Sidwell, R A; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smith, R P; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stevenson, K; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Sznajder, A; Talby, M; Tamburello, P; Taylor, W; Telford, P; Temple, J; Tiller, B; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; van den Berg, P J; Kooten, R Van; van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Seguier, F; Vint, P; Vlimant, J-R; Toerne, E Von; Voutilainen, M; Vreeswijk, M; Wahl, H D; Wang, L; Warchol, J; Watts, G; Wayne, M; Weber, M; Weerts, H; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Xie, Y; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, C; Yu, J; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhao, Z; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G

    2006-09-15

    We present a search for supersymmetry in the R-parity violating resonant production and decay of smuons and muon sneutrinos in the channels mu-->chi(1)(0)mu, mu-->chi(2,3,4)(0)mu, and nu(mu)-->chi(1,2)(+/-)mu. We analyzed 0.38 fb(-1) of integrated luminosity collected between April 2002 and August 2004 with the D0 detector at the Fermilab Tevatron Collider. The observed number of events is in agreement with the standard model expectation, and we calculate 95% C.L. limits on the slepton production cross section times branching fraction to gaugino plus muon, as a function of slepton and gaugino masses. In the framework of minimal supergravity, we set limits on the coupling parameter lambda(211)('), extending significantly previous results obtained in Run I of the Tevatron and at the CERN LEP collider.

  3. Measurement of Beam Tunes in the Tevatron Using the BBQ System

    Energy Technology Data Exchange (ETDEWEB)

    Edstrom, Dean R.; /Indiana U.

    2009-04-01

    Measuring the betatron tunes in any synchrotron is of critical importance to ensuring the stability of beam in the synchrotron. The Base Band Tune, or BBQ, measurement system was developed by Marek Gasior of CERN and has been installed at Brookhaven and Fermilab as a part of the LHC Accelerator Research Program, or LARP. The BBQ was installed in the Tevatron to evaluate its effectiveness at reading proton and antiproton tunes at its flattop energy of 980 GeV. The primary objectives of this thesis are to examine the methods used to measure the tune using the BBQ tune measurement system, to incorporate the system into the Fermilab accelerator controls system, ACNET, and to compare the BBQ to existing tune measurement systems in the Tevatron.

  4. The like-sign dimuon charge asymmetry at the Tevatron: corrections from B meson fragmentation

    CERN Document Server

    Mitov, Alexander

    2011-01-01

    The existing predictions for the like-sign dimuon charge asymmetry at the Tevatron are expressed in terms of parameters related to B mesons' mixing and inclusive production fractions. We show that in the realistic case when phase-space cuts are applied, the asymmetry depends also on the details of the production mechanism for the B mesons. In particular, it is sensitive to the difference in the fragmentation functions of B^0_d and B^0_s mesons. We estimate these fragmentation effects and find that they shift the theory prediction for this observable by approximately 10%. We also point out the approximately 20% sensitivity of the asymmetry depending on which set of values for the B meson production fractions is used: as measured at the Z pole or at the Tevatron. The impact of these effects on the extraction of A^s_{SL} from the D\\O measurement is presented.

  5. LHC and Tevatron results on the $t\\bar{t}$ differential cross sections

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00213443; The ATLAS collaboration

    2017-01-01

    This note describes a review of the most recent $t\\bar{t}$ differential cross sections measurement per- formed by LHC and Tevatron experiments. I will describe the measurements of fiducial and full phase-space differential cross sections based on events with exactly two, one or zero charged leptons in the final state. These results are compared to predictions made with next-to-leading order or next-to-next-to leading order numerical calculations.

  6. Long-Term Simulation of Beam-Beam Effects in the Tevatron at Collision Energy

    Energy Technology Data Exchange (ETDEWEB)

    Kabel, A.C.; Cai, Y.; /SLAC; Sen, T.; /Fermilab

    2006-02-10

    The beam-beam effect is a significant source of nonlinearities in the Tevatron. We have developed a code which allows us to estimate its contribution to the finite lifetime of the anti-proton beam, both at collision and injection energy, by tracking realistic particle distribution for a high number of terms and extrapolating from the particle loss rate. We describe the physical modeling underlying the code and give benchmarking results.

  7. Limits on Z' production at the Tevatron using CDF and D0 data

    CERN Document Server

    Pillai, M K

    1996-01-01

    A search for a neutral heavy vector gauge boson, $\\zp$, was conducted in CDF and $\\approx$ 90pb$^{-1}$ dielectron data obtained at D0 using the Tevatron accelerator at Fermilab. We obtain the 95\\% Confidence Limits on the cross-section $\\times$ branching ratio for a $\\zp$ decaying to dileptons based on the combined data from CDF and D0. Of interest is the excluded mass region from E$_6$ based models.

  8. Tevatron Beam Halo Collimation System: Design, Operational Experience and New Methods

    OpenAIRE

    Mokhov, Nikolai; Annala, Jerry; Carrigan, Richard; Church, Michael; Drozhdin, Alexander; Johnson, Todd; Robert, Reilly; Shiltsev, Vladimir; Stancari, Guilio; Still, Dean; Valishev, Alexander; Zhang, Xiao-Long; Zvoda, Viktoriya

    2012-01-01

    Collimation of proton and antiproton beams in the Tevatron collider is required to protect CDF and D0 detectors and minimize their background rates, to keep irradiation of superconducting magnets under control, to maintain long-term operational reliability, and to reduce the impact of beam-induced radiation on the environment. In this article we briefly describe the design, practical implementation and performance of the collider collimation system, methods to control transverse and longitudi...

  9. Phenomenological study of the atypical heavy flavor production observed at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Apollinari, G.; Barone, M.; Fiori, I.; Giromini, P.; Happacher, F.; Miscetti, S.; Parri, A.; Ptohos, F.; /Frascati /Fermilab /INFN, Pisa /Cyprus U.

    2005-11-01

    The authors address known discrepancies between the heavy flavor properties of jets produced at the Tevatron collider and the prediction of conventional-QCD simulations. In this study, they entertain the possibility that these effects are real and due to new physics. They show that all anomalies can be simultaneously fitted by postulating the additional pair production of light bottom squarks with a 100% semileptonic branching fraction.

  10. Consequences of the extra SM families on the Higgs boson production at Fermilab Tevatron and LHC

    CERN Document Server

    Arik, E; Cetin, S A; Sultansoy, S F

    2002-01-01

    The latest electroweak precission data allow the existence of additional chiral generations in the standard model. We study the influence of extra generations on the production of SM Higgs boson at hadron colliders. Due to the enhancement of the gluon fusion channel, the ``golden mode'' becomes more promising even at upgraded Tevatron. Furthermore, the formation of the fourth family quarkonia with the subsequent $\\eta_{4}\\to ZH$ decay introduces additional tool for the investigation of the Higgs boson properties.

  11. Di-J/psi production at the Tevatron and the LHC

    CERN Document Server

    Lansberg, Jean-Philippe

    2016-01-01

    We briefly review recent results which we have obtained in the study of J/psi-pair production at the Tevatron and the LHC. We claim that the existing data set from CMS and D0 point at a significant double-parton-scattering contribution with an effective cross section smaller than that for jet-related observables. We have also derived simple relations involving feed-down fractions from excited states which can help in disentangling the single from the double scatterings.

  12. Development of 3D beam-beam simulation for the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Stern, E.; Amundson, J.; Spentzouris, P.; Valishev, A.; /Fermilab; Qiang, J.; Ryne, R.; /LBL, Berkeley

    2007-06-01

    We present status of development of a 3D Beam-Beam simulation code for simulating the Fermilab Tevatron collider. The essential features of the code are 3D particle-in-cell Poisson solver for calculating the Beam-Beam electromagnetic interactions with additional modules for linear optics, machine impedance and chromaticity, and multiple bunch tracking. The simulations match synchrobetatron oscillations measured at the VEPP-2M collider. The impedance calculations show beam instability development consistent with analytic expressions.

  13. DESIGN OF THE MULTIORDER INTRAOCULAR LENSES

    Directory of Open Access Journals (Sweden)

    V. G. Kolobrodov

    2015-01-01

    Full Text Available Intraocular lenses (IOLs are used to replace the natural crystalline lens of the eye. Just few basic designs of IOLs are used clinically. Multiorder diffractive lenses (MODL which operate simultaneously in several diffractive orders were proposed to decrease the chromatic aberration. Properties analysis of MODL showed a possibility to use them to develop new designs of IOLs. The purpose of this paper was to develop a new method of designing of multiorder intraocular lenses with decreased chromatic aberration. The theoretical research of the lens properties was carried out. The diffraction efficiency dependence with the change of wavelength was studied. A computer simulation of MODL in a schematic model of the human eye was carried out. It is found the capability of the multiorder diffractive lenses to focus polychromatic light into a segment on the optical axis with high diffraction efficiency. At each point of the segment is present each component of the spectral range, which will build a color image in combination. The paper describes the new design method of intraocular lenses with reduced chromaticism and with endless adaptation. An optical system of an eye with an intraocular lens that provides sharp vision of objects located at a distance of 700 mm to infinity is modeled.

  14. Therapeutic contact lenses: a patent review.

    Science.gov (United States)

    Dixon, Phillip; Shafor, Chancellor; Gause, Samuel; Hsu, Kuan-Hui; Powell, Kristin Conrad; Chauhan, Anuj

    2015-01-01

    Ophthalmic drugs are almost exclusively delivered via eye drops in spite of several deficiencies, including low bioavailability and poor compliance. Contact lenses have the potential to increase bioavailability by an order of magnitude, while also improving compliance. In this review, the authors summarize advances in therapeutic contact lenses. The major focus of the review is on patents on drug-eluting contact lenses, but non-drug-eluting contacts that offer a therapeutic benefit are also included. The content is divided based on the broad technology of the patent, including novel materials, molecular imprinting, diffusion barriers, colloid encapsulation, surface modification, layering, and other novel approaches. In addition to patents, research publications are also included to facilitate the understanding of the mechanisms and challenges. Among all non-invasive alternatives, contact lenses offer the highest bioavailability to the cornea due to the location of the lens in the immediate vicinity of the cornea. Several approaches have been patented to improve contact lens design for an extended release duration of drugs. Many technologies have successfully integrated suitable drug release profiles into contact lenses, but drug-eluting contacts are not yet commercialized likely due to regulatory challenges, including the high costs of clinical trials.

  15. Multifocal versus monofocal intraocular lenses after cataract extraction

    Directory of Open Access Journals (Sweden)

    Daniel Calladine

    Full Text Available BACKGROUND: Good unaided distance visual acuity is now a realistic expectation following cataract surgery and intraocular lens (IOL implantation. Near vision, however, still requires additional refractive power, usually in the form of reading glasses. Multiple optic (multifocal IOLs are available which claim to allow good vision at a range of distances. It is unclear whether this benefit outweighs the optical compromises inherent in multifocal IOLs. OBJECTIVES: The objective of this review was to assess the effects of multifocal IOLs, including effects on visual acuity, subjective visual satisfaction, spectacle dependence, glare and contrast sensitivity, compared to standard monofocal lenses in people undergoing cataract surgery. METHODS: Search methods: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register, The Cochrane Library 2012, Issue 2, MEDLINE (January 1946 to March 2012, EMBASE (January 1980 to March 2012, the metaRegister of Controlled Trials (mRCT (www.controlled-trials.com, ClinicalTrials.gov (www.clinicaltrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP (www.who.int/ictrp/search/en. We did not use any date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 6 March 2012. We searched the reference lists of relevant articles and contacted investigators of included studies and manufacturers of multifocal IOLs for information about additional published and unpublished studies. Selection criteria: All randomised controlled trials comparing a multifocal IOL of any type with a monofocal IOL as control were included. Both unilateral and bilateral implantation trials were included. Data collection and analysis: Two authors collected data and assessed trial quality. Where possible, we pooled data from the individual studies using a random-effects model, otherwise we tabulated data. MAIN RESULTS: Sixteen completed trials

  16. Hyphal penetration of worn hydrogel contact lenses by Fusarium.

    Science.gov (United States)

    Ahearn, Donald G; Zhang, Shangtong; Ward, Michael A; Simmons, Robert B; Stulting, R Doyle

    2009-09-01

    To determine the relative susceptibility of worn and unworn hydrogel contact lenses to penetration by hyphae of the Fusarium solani-Fusarium oxysporum species complex. Hydrogel contact lenses (lotrafilcon A, balafilcon A, senofilcon A, galyfilcon A, and etafilcon A) were removed from their original packages and placed directly on the eyes of 24 experienced contact lens wearers for 8-9 hours. Lenses were removed, each placed in 3.0 mL sterile phosphate buffered saline (PBS), and inoculated with 10 conidia of fusaria. Similar sets of unworn lenses were soaked in Sabouraud's dextrose broth for 2 hours prior to exposure to fusaria conidia in PBS. The entire surface of lenses was examined with microscopy for 14 days for the development of coiled hyphae in the lens matrix (ie, penetration pegs [PP]). A total of 21 of 54 worn hydrogel lenses representing 4 types of silicone hydrogel and one type of hydroxyethylmethacrylate lens were penetrated by the fusaria. Compared to unworn lenses, 9 of the 21 PP-positive worn lenses showed earlier and more extensive penetration than seen with the unworn lenses. Several worn lenses compared to their unworn counterparts showed negligible or delayed penetration. Worn hydrogel contact lenses without a history of exposure to disinfection solutions compared to unworn lenses of similar status may show enhanced or decreased susceptibilities to penetration by Fusarium. This suggests that tear characteristics are an additional factor in the invasive contamination of hydrogel contact lenses by Fusarium.

  17. PDF dependence of Higgs cross sections at the Tevatron and LHC: response to recent criticism

    CERN Document Server

    Thorne, R S

    2011-01-01

    We respond to some criticism questioning the validity of the current Standard Model Higgs exclusion limits at the Tevatron, due to the significant dependence of the dominant production cross section from gluon-gluon fusion on the choice of parton distribution functions (PDFs) and the strong coupling (alpha_S). We demonstrate the ability of the Tevatron jet data to discriminate between different high-x gluon distributions, performing a detailed quantitative comparison to show that fits not explicitly including these data fail to give a good description. In this context we emphasise the importance of the consistent treatment of luminosity uncertainties. We comment on the values of alpha_S obtained from fitting deep-inelastic scattering data, particularly the fixed-target NMC data, and we show that jet data are needed for stability. We conclude that the Higgs cross-section uncertainties due to PDFs and alpha_S currently used by the Tevatron and LHC experiments are not significantly underestimated, contrary to so...

  18. Di-boson production and SM SUSY Higgs searches at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Elvira, V.Daniel; /Fermilab

    2005-07-01

    The discovery of the Higgs boson would be a major success for the Standard Model (SM) and would provide further insights into the electroweak symmetry breaking mechanism. This report contains the latest results from the D0 and CDF Tevatron experiments on searches for the SM Higgs produced from gluon fusion with H {yields} WW, and in association with a W boson. It also includes searches for a supersymmetric Higgs in the b{bar b} and {tau}{sup +}{tau}{sup -} decay channels. The study of di-boson production at the Tevatron is important to understand backgrounds in high mass Higgs searches. It also provides a test of the SM through the measurement of the production cross section and the gauge boson self couplings. This paper includes measurements of the WW, W{gamma}, and WZ production cross sections, as well as limits on the anomalous couplings associated with the WW{gamma} and WWZ interactions. The results are based on sets of up to 320 pb{sup -1} of data collected by the D0 and CDF experiments at the {bar p}p Tevatron collider, running at a center-of-mass energy of 1.96 TeV.

  19. Calcification of different designs of silicone intraocular lenses in eyes with asteroid hyalosis.

    Science.gov (United States)

    Stringham, Jack; Werner, Liliana; Monson, Bryan; Theodosis, Raymond; Mamalis, Nick

    2010-08-01

    To describe the association between calcification of older and newer designs of silicone intraocular lenses (IOLs) and asteroid hyalosis. Case series with clinicopathologic correlation. Sixteen silicone IOLs explanted because of decreased visual acuity associated with opacifying deposits on the posterior optic surface. All 16 lenses underwent gross and light microscopic analyses. Selected lenses underwent alizarin red staining or scanning electron microscopy coupled with energy dispersive x-ray spectroscopy for elemental composition. Clinical data in each case were obtained by a questionnaire sent to the explanting surgeons. Clinical data in relation to 111 hydrophilic acrylic lenses explanted because of calcification also were assessed for comparison. Deposit morphologic features and location were evaluated under gross and light microscopy. The calcified nature of the deposits was assessed by histochemical staining and surface analyses. Clinical data obtained included age at IOL implantation, gender, implantation and explantation dates, as well as history of neodymium:yttrium-aluminum-garnet laser treatment. The presence of asteroid hyalosis in the affected eye was investigated for the explanted silicone and hydrophilic acrylic lenses. The 16 lenses were of 8 designs manufactured from different silicone materials, which were explanted 9.21+/-3.66 years after implantation. Neodymium:yttrium-aluminum-garnet laser applications performed in 12 cases partially removed deposits from the lens, followed by a gradual increase in their density after the procedures. The presence of asteroid hyalosis was confirmed in 13 cases; no notes regarding this condition were found in patient charts in the other 3 cases. The deposits were only on the posterior optic surface of the silicone lenses and were composed of calcium and phosphate. A history of asteroid hyalosis was not found in relation to any of the 111 cases of postoperative calcification of hydrophilic acrylic lenses

  20. Soft Contact Lenses Safe for Kids and Teens, Review Finds

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_167037.html Soft Contact Lenses Safe for Kids and Teens, Review Finds Infection ... 2017 WEDNESDAY, July 5, 2017 (HealthDay News) -- Soft contact lenses are as safe for children and teens as ...

  1. Soft-contact-lenses-induced complications

    Directory of Open Access Journals (Sweden)

    Suvajac Gordana

    2008-01-01

    Full Text Available Background/Aim. Soft contact lenses occupy significant place in ophthalmology, both in the correction of refraction anomalies and in the treatment of many eye diseases. The number of patients that wear soft contact lenses for the purpose of correcting ametropia is constantly increasing. Due to the increasing number of wearers, the percentage of complications that can lead to serious eye damage and serious vision loss is also increasing. The aim of this study was to point out the most common complications related to soft contact lens use. Methods. In the period from 1995−2004 this prospective study included 510 patients wearing soft contact lenses for correcting ametropia. None of the patients wore contact lenses before and none suffered from any system or local diseases that could affected the development of eventual complications. The study took seven years with the patients who wore conventional lenses and three years with those who wore replacement contact lenses. All the necessary ophthalmologic examinations were done (visual acuity, refractokeratometry, the quantity of tear film, biomicroscopic examination of anterior eye segment. All the complications were filmed by video camera. Results. Of all the patients, 19 had blepharitis, 73 suffered from “dry eye”, 57 had conjunctival hyperemia, 12 had conjunctivitis, 34 had gigantopapillary conjunctivitis (GPC, 93 had punctiform epitheliopathy, 20 had corneal infiltration, one patient had keratitis, 91 had corneal vascularisation, and 95 patients had corneal deposits. Conclusion. Both the type and frequency of complications related to soft contact lens use in our group of patients, proved to be significant. Some of this complications (keratitis can significantly damage vision and lead to loss of vision and sometimes can require operative treatment.

  2. SARCS strong-lensing galaxy groups. II. Mass-concentration relation and strong-lensing bias

    Science.gov (United States)

    Foëx, G.; Motta, V.; Jullo, E.; Limousin, M.; Verdugo, T.

    2014-12-01

    Aims: Various studies have shown a lensing bias in the mass-concentration relation of cluster-scale structures that is the result of an alignment of the major axis and the line of sight. In this paper, we aim to study this lensing bias through the mass-concentration relation of galaxy groups, thus extending observational constraints to dark matter haloes of mass ~1013-1014 M⊙. Methods: Our work is based on the stacked weak-lensing analysis of a sample of 80 strong-lensing galaxy groups. By combining several lenses, we significantly increase the signal-to-noise ratio of the lensing signal, thus providing constraints on the mass profile that cannot be obtained for individual objects. The resulting shear profiles were fitted with various mass models, among them the Navarro-Frank-White (NFW) profile, which provides an estimate of the total mass and of the concentration of the composite galaxy groups. Results: The main results of our analysis are the following: (i) the lensing signal does not allow us to firmly distinguish between a simple singular isothermal sphere mass distribution and the expected NFW mass profile; (ii) we obtain an average concentration c200 = 8.6-1.3+2.1 that is much higher than the value expected from numerical simulations for the corresponding average mass M200 = 0.73-0.10+0.11 × 1014 M⊙; (iii) the combination of our results with those at larger mass scales gives a mass-concentration relation c(M) of more than two decades in mass, whose slope disagrees with predictions from numerical simulations using unbiased populations of dark matter haloes; (iv) our combined c(M) relation matches results from simulations that only used haloes with a large strong-lensing cross-section, that is, elongated with a major axis close to the line of sight; (v) for the simplest case of prolate haloes, we estimate a lower limit on the minor-to-major axis ratio a/c = 0.5 for the average SARCS galaxy group with a toy model. Conclusions: Our analysis based on galaxy

  3. High-speed optical signal processing using time lenses

    DEFF Research Database (Denmark)

    Galili, Michael; Hu, Hao; Guan, Pengyu

    2015-01-01

    This paper will discuss time lenses and their broad range of applications. A number of recent demonstrations of complex high-speed optical signal processing using time lenses will be outlined with focus on the operating principle.......This paper will discuss time lenses and their broad range of applications. A number of recent demonstrations of complex high-speed optical signal processing using time lenses will be outlined with focus on the operating principle....

  4. Achromatic Cooling Channel with Li Lenses

    Energy Technology Data Exchange (ETDEWEB)

    Balbekov, V. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2002-04-29

    A linear cooling channel with Li lenses, solenoids, and 201 MHz RF cavities is considered. A special lattice design is used to minimize chromatic aberrations by suppression of several betatron resonances. Transverse emittance of muon beam decreases from 2 mm to 0.5 mm at the channel of about 110 m length. Longitudinal heating is modest, therefore transmission of the channel is rather high: 96% without decay and 90% with decay. Minimal beam emittance achievable by similar channel estimated as about 0.25 mm at surface field of Li lenses 10 T.

  5. Rigid gas permeable lenses and patient management.

    Science.gov (United States)

    Terry, R; Schnider, C; Holden, B A

    1989-01-01

    The introduction of new rigid gas permeable (RGP) contact lens materials provides the practitioner with a number of alternatives for patient management. But whatever the lens materials used, problems related to the lenses, care and maintenance solutions, and patients may arise. This paper examines concerns such as parameter instability, durability of lenses, compatibility of materials and solutions, patient education and compliance, 3 and 9 o'clock staining, corneal distortion, and lid changes. Suggestions are made on ways to avoid or minimize problems related to RGP lens wear.

  6. Robotic Monitoring of Gravitationally Lensed Quasars

    Directory of Open Access Journals (Sweden)

    Luis J. Goicoechea

    2010-01-01

    Full Text Available We report on the first observational phase of the Liverpool Quasar Lens Monitoring (LQLM project. This mainly consisted of the optical follow-up of three lensed quasars using the 2 m Liverpool Robotic Telescope. The observational subprogram started in January 2005 and was completed in July 2007. We also describe our photometric approaches (including two pipelines to extract accurate and reliable fluxes of images of lensed quasars, the performance of the telescope when taking modest nightly exposures of lens systems, and the main scientific results from the observed light curves. The LQLM archive and the current status of the project (second phase are also outlined.

  7. Abrasion Testing Of Coated Plastic Lenses

    Science.gov (United States)

    Thiebaud, F.; Wegelin, H. P.

    1988-07-01

    The tumble abrasion test proposed by J.M. Young and J.D.Masso has been modified in order to produce uniform scratching of the lens surface under test and in order to simulate closely damage which occurs during normal wear in the field. The uniformity of the abrasion enables a quantitative measurement of the abrasion resistance by a simple determination of the scattered light. The test has been applied to coated and uncoated plastic ophthalmic lenses. The results show that the scratch resistance of the coated lenses depends strongly on the composition and on the thickness of the coating.

  8. Successful monovision contact lens wearers refitted with bifocal contact lenses.

    Science.gov (United States)

    Situ, Ping; Du Toit, Rènée; Fonn, Desmond; Simpson, Trefford

    2003-07-01

    Should successful monovision contact lens wearers be refitted with bifocal lenses? Fifty current monovision lens wearers were fitted with ACUVUE Bifocal contact lenses (Johnson & Johnson Vision Care, Jacksonville, FL). Visual function and subjective vision ratings were assessed with habitual monovision lenses at the first visit and then were repeated at the end of 6 months while wearing bifocal lenses. Lens preference was determined at the end of the 6-month study, and the subjects were called 1 year later to repeat the lens preference questionnaire. Forty (80%) subjects completed the 6-month study; nine discontinued for visual reasons. At the end of 6 months of wear, 68% preferred bifocal lenses and 25% preferred monovision. Of the subjects who were contacted a year later, 53% were still wearing bifocal lenses. High-contrast visual acuity and letter contrast sensitivity at distance was the same for monovision and bifocal lenses, but low-contrast acuity was better with monovision. Intermediate low- and high-contrast acuity and 3-meter and near stereoscopic acuity were better with bifocal lenses. Near high- and low-contrast acuity were better with monovision. All subjective ratings, except near vision in poor lighting, were significantly greater with bifocal lenses. It is possible to refit successful monovision lens wearers with simultaneous vision bifocal lenses, and these lenses should be considered as an alternative method for the correction of presbyopia. In addition, subjective responses to bifocal lenses may not be reflective of visual function measurements.

  9. Bacterial and fungal biofilm formation on contact lenses and their susceptibility to lens care solutions

    Directory of Open Access Journals (Sweden)

    Siddharth Kackar

    2017-01-01

    Full Text Available Background: Microbial biofilm formation on contact lenses and lens storage cases may be a risk factor for contact lens-associated corneal infections. Various types of contact lens care solutions are used to reduce microbial growths on lenses. Objectives: The present study aimed at comparing the growths of biofilms on the different contact lenses and lens cases. The study also aimed at determining the effect of lens care solutions and bacteriophage on these biofilms. Materials and Methods: One type of hard lens and two types of soft lenses were used for the study. The organisms used were Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 60193 and Escherichia coli ATCC 25922. Biofilm production was performed by modified O'Toole and Kolter method and effect of lens cleaning solutions and a crude coliphage on biofilms was also studied. Results were visualised using scanning electron microscopy and quantitated by colony counting method and spectrophotometric measurement of optical density (OD. Statistical analysis was done by SPSS 11.5, Kruskal–Wallis test and Chi-square test. Results: Soft lens cleaning solutions had a significant inhibitory effect (P = 0.020 on biofilm formation on soft lenses and also lens cases (P < 0.001. Soft lens cleaning solution 2 was more efficient than solution 1. However, no such inhibitory effect was observed with regard to hard lens cleaning solution, but for a significant reduction in the OD values (P < 0.001. There was no significant inhibitory effect by bacteriophages. Conclusion: This study showed the importance of selecting the appropriate lens cleaning solution to prevent biofilm production on contact lenses.

  10. W boson production and mass at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Stelzer-Chilton, Oliver; /Toronto U.

    2005-06-01

    The CDF and D0 collaborations have analyzed up to {approx} 200 pb{sup -1} of Run 2 physics data to measure W production properties such as the W cross section, the W width, lepton universality and the W charge asymmetry. From the cross section measurements, CDF obtains a lepton universality of g{sub {mu}}/g{sub e} = 0.998 {+-} 0.012 and g{sub {tau}}/g{sub e} = 0.99 {+-} 0.04 and an indirect W width of {Lambda}{sub W} = 2079 {+-} 41 MeV. D0 measured the W width directly and finds {Lambda}{sub W} = 2011 {+-} 142 MeV. CDF has estimated the uncertainties on the W boson mass measurements in the electron and muon decay channels and obtains an overall uncertainty of 76 MeV.

  11. Analysis of luminosity distributions of strong lensing galaxies: subtraction of diffuse lensed signal

    Science.gov (United States)

    Biernaux, J.; Magain, P.; Hauret, C.

    2017-08-01

    Context. Strong gravitational lensing gives access to the total mass distribution of galaxies. It can unveil a great deal of information about the lenses' dark matter content when combined with the study of the lenses' light profile. However, gravitational lensing galaxies, by definition, appear surrounded by lensed signal, both point-like and diffuse, that is irrelevant to the lens flux. Therefore, the observer is most often restricted to studying the innermost portions of the galaxy, where classical fitting methods show some instabilities. Aims: We aim at subtracting that lensed signal and at characterising some lenses' light profile by computing their shape parameters (half-light radius, ellipticity, and position angle). Our objective is to evaluate the total integrated flux in an aperture the size of the Einstein ring in order to obtain a robust estimate of the quantity of ordinary (luminous) matter in each system. Methods: We are expanding the work we started in a previous paper that consisted in subtracting point-like lensed images and in independently measuring each shape parameter. We improve it by designing a subtraction of the diffuse lensed signal, based only on one simple hypothesis of symmetry. We apply it to the cases where it proves to be necessary. This extra step improves our study of the shape parameters and we refine it even more by upgrading our half-light radius measurement method. We also calculate the impact of our specific image processing on the error bars. Results: The diffuse lensed signal subtraction makes it possible to study a larger portion of relevant galactic flux, as the radius of the fitting region increases by on average 17%. We retrieve new half-light radii values that are on average 11% smaller than in our previous work, although the uncertainties overlap in most cases. This shows that not taking the diffuse lensed signal into account may lead to a significant overestimate of the half-light radius. We are also able to measure

  12. Strong lensing interferometry for compact binaries

    NARCIS (Netherlands)

    Pen, U.L.; Yang, I.S.

    2015-01-01

    We propose a possibility to improve the current precision measurements on compact binaries. When the orbital axis is almost perpendicular to our line of sight, a pulsar behind its companion can form two strong lensing images. These images cannot be resolved, but we can use multiwavelength

  13. Studying dark matter haloes with weak lensing

    NARCIS (Netherlands)

    Velander, Malin Barbro Margareta

    2012-01-01

    Our Universe is comprised not only of normal matter but also of unknown components: dark matter and dark energy. This Thesis recounts studies of dark matter haloes, using a technique known as weak gravitational lensing, in order to learn more about the nature of these dark components. The haloes

  14. Zoom microscope objective using electrowetting lenses.

    Science.gov (United States)

    Li, Lei; Wang, Di; Liu, Chao; Wang, Qiong-Hua

    2016-02-08

    We report a zoom microscope objective which can achieve continuous zoom change and correct the aberrations dynamically. The objective consists of three electrowetting liquid lenses and two glass lenses. The magnification is changed by applying voltages on the three electrowetting lenses. Besides, the three electrowetting liquid lenses can play a role to correct the aberrations. A digital microscope based on the proposed objective is demonstrated. We analyzed the properties of the proposed objective. In contrast to the conventional objectives, the proposed objective can be tuned from ~7.8 × to ~13.2 × continuously. For our objective, the working distance is fixed, which means no movement parts are needed to refocus or change its magnification. Moreover, the zoom objective can be dynamically optimized for a wide range of wavelength. Using such an objective, the fabrication tolerance of the optical system is larger than that of a conventional system, which can decrease the fabrication cost. The proposed zoom microscope objective cannot only take place of the conventional objective, but also has potential application in the 3D microscopy.

  15. Quantum Spin Lenses in Atomic Arrays

    Directory of Open Access Journals (Sweden)

    A. W. Glaetzle

    2017-09-01

    Full Text Available We propose and discuss quantum spin lenses, where quantum states of delocalized spin excitations in an atomic medium are focused in space in a coherent quantum process down to (essentially single atoms. These can be employed to create controlled interactions in a quantum light-matter interface, where photonic qubits stored in an atomic ensemble are mapped to a quantum register represented by single atoms. We propose Hamiltonians for quantum spin lenses as inhomogeneous spin models on lattices, which can be realized with Rydberg atoms in 1D, 2D, and 3D, and with strings of trapped ions. We discuss both linear and nonlinear quantum spin lenses: in a nonlinear lens, repulsive spin-spin interactions lead to focusing dynamics conditional to the number of spin excitations. This allows the mapping of quantum superpositions of delocalized spin excitations to superpositions of spatial spin patterns, which can be addressed by light fields and manipulated. Finally, we propose multifocal quantum spin lenses as a way to generate and distribute entanglement between distant atoms in an atomic lattice array.

  16. Cosmology with Strong-lensing Systems

    Science.gov (United States)

    Cao, Shuo; Biesiada, Marek; Gavazzi, Raphaël; Piórkowska, Aleksandra; Zhu, Zong-Hong

    2015-06-01

    In this paper, we assemble a catalog of 118 strong gravitational lensing systems from the Sloan Lens ACS Survey, BOSS emission-line lens survey, Lens Structure and Dynamics, and Strong Lensing Legacy Survey and use them to constrain the cosmic equation of state. In particular, we consider two cases of dark energy phenomenology: the XCDM model, where dark energy is modeled by a fluid with constant w equation-of-state parameter, and in the Chevalier-Polarski-Linder (CPL) parameterization, where w is allowed to evolve with redshift, w(z)={{w}0}+{{w}1}\\frac{z}{1 + z} . We assume spherically symmetric mass distribution in lensing galaxies, but we relax the rigid assumption of the SIS model in favor of a more general power-law index γ, also allowing it to evolve with redshifts γ (z). Our results for the XCDM cosmology show agreement with values (concerning both w and γ parameters) obtained by other authors. We go further and constrain the CPL parameters jointly with γ (z). The resulting confidence regions for the parameters are much better than those obtained with a similar method in the past. They are also showing a trend of being complementary to the Type Ia supernova data. Our analysis demonstrates that strong gravitational lensing systems can be used to probe cosmological parameters like the cosmic equation of state for dark energy. Moreover, they have a potential to judge whether the cosmic equation of state evolved with time or not.

  17. Ocular Straylight with Different Multifocal Contact Lenses.

    Science.gov (United States)

    Łabuz, Grzegorz; López-Gil, Norberto; van den Berg, Thomas J T P; Vargas-Martín, Fernando

    2017-04-01

    Multifocal contact lenses have been growing in popularity as a modality to correct presbyopic eyes, although visual side effects such as disability glare have been reported. The objective of this study was to investigate the effect of multifocal contact lenses on disability glare by means of ocular straylight. A prospective randomized, comparative study was performed that included 16 subjects free of ocular pathology. Straylight was measured using a commercial straylight meter with the natural and dilated pupil. Participants were fitted with Proclear Multifocal (Distance/Near), ACUVUE Oasys for Presbyopia, and Air Optix Aqua Multifocal randomized to the left or right eye. Straylight measurements were repeated with the contact lens in situ after the pupil dilation. Results obtained with the dilated pupil without contact lens acted as a control. Diameter of the natural and dilated pupil was 2.87 ± 0.40 mm and 7.45 ± 0.86 mm, respectively (P lenses, a significant difference was only found between Air Optix and the control group (P = .006). The latter showed also slightly increased light scatter. A difference in measured straylight was found between the studied multifocal lenses. The observed variability and the straylight-pupil size dependency should be taken into account to avoid elevated straylight in multifocal contact lens wearers. The reason for the observed differences in straylight must be the subject of future studies.

  18. [Compensation for presbyopia using contact lenses].

    Science.gov (United States)

    Bischoff, G

    2006-08-01

    Contact lens fitting for presbyotic patients needs more than simple fitting shill; patients need additional psychological support. The wearer has to accept optical quality reduction due to the multifocality of the lens design. In general, the technical fitting of presbyotic contact lenses is comparable to monofocal systems. They work with the same rules of performance. The difference lies in the principles of correction by the lens itself. Simple presbyotic systems use uncorrected optical aberration to widen depth perception. These lenses are suitable for young presbyopes, up to a need of 1 diopter plus power for near vision. Uncorrected aspherical designs have a multifocal effect which can be used for presbyotic lenses. There are contact lenses on the market with simultaneous imaging, which is based on concentric rings around the near or distance centre. Another principles are based on segmented reading portions in the lower part of the lens, also called alternating systems. These very few design variations are the basis for the various specific models which are sold on the market today. The results of the fitting can never be foreseen as subjective and psychological aspects of the wearer overlay the objective results. Thus, the fitter needs experience and patient understanding, combined with fundamental knowledge of the specific lens type used.

  19. Chromagen lenses and abnormal colour perception

    Directory of Open Access Journals (Sweden)

    O. Matthew Oriowo

    2011-12-01

    Full Text Available Background: The Chromagen lens system comprises of tinted spectacle or contact lenses, each with a specific colour wavelength filter which controls the spectra of the light entering the eye. This study investigated whether spectacle-mounted Chromagen lenses would enhance colour perception in individuals with abnormal colour vision.Methods: The Ishihara colour test was used to test for colour vision deficiency (CVD and also to evaluate the effect of the Chromagen spectacle lens on colour perception in 13 subjects. An Oculus Anomaloscope was used to confirm and sub-classify the types of CVD. Subjects comprised of school age children from the Riyadh area in Saudi Arabia.Results: The distribution amongst the male participants comprised two subjects with protanomaly, two with protanopia, five with deuteranomaly, and two with deuteranopia. Amongst the two female participants, one subject showed deuteranomaly, and one showed protanomaly. Different types of Chromagen spectacle lenses displayed some levels of colour vision enhancement depending on type of CVD.Conclusion: The findings support the notion that chromagen lenses could enhance colour vision perception in some cases of red-green colour vision defects. Clients with CVD should be managed on an individual case basis. (S Afr Optom 2011 70(2 69-74 

  20. Ocean Freshwater Lenses: Prevalence and Persistence

    Science.gov (United States)

    Schanze, Julian; Lagerloef, Gary; Schmitt, Raymond

    2017-04-01

    During the Salinity Processes in the Upper Ocean Regional Study II (SPURS-II), a novel dataset was collected from an underway system sampling seawater at the surface, 2m, 3m and 5m. The surface measurements are performed using a boom-mounted suction hose and a peristaltic pump, as well as a shipboard apparatus with multiple de-bubbling stages. The data collected during this cruise reveal approximately fifty freshwater lenses in the Intertropical Convergence Zone (ITCZ), sampled between August 15 and September 20 under several different wind- and precipitation-regimes. Preliminary analysis shows that that the persistence of oceanic freshwater lenses is strongly dependent on the evolution of wind speed as well as the total amount of precipitated water. The results are analyzed in a number of case studies of different types of freshwater lenses, in which the balance between precipitation and wind-driven mixing is elucidated. While the limited sample size restricts the validity of the findings to the SPURS-II region, centered around 125°W, 10°N, during the late boreal summer of 2016, it has important consequences for modelling of freshwater lenses and their impact on satellite retrievals of salinity.

  1. GRAVITATIONAL LENSES AND UNCONVENTIONAL GRAVITY THEORIES

    NARCIS (Netherlands)

    BEKENSTEIN, JD; SANDERS, RH

    1994-01-01

    We study gravitational lensing by clusters of galaxies in the context of the generic class of unconventional gravity theories which describe gravity in terms of a metric and one or more scalar fields (called here scalar-tensor theories). We conclude that, if the scalar fields have positive energy,

  2. Coatings and Tints of Spectacle Lenses

    Directory of Open Access Journals (Sweden)

    H. Zeki Büyükyıldız

    2012-10-01

    Full Text Available Spectacle lenses are made of mineral or organic (plastic materials. Various coatings and tints are applied to the spectacle lenses according to the characteristic of the lens material, and for the personal needs and cosmetic purpose. The coatings may be classified in seven groups: 1 Anti-reflection coatings, 2 Hard coatings, 3 Clean coat, 4 Mirror coatings, 5 Color tint coating (one of coloring processes, 6 Photochromic coating (one of photochromic processes, and 7 Anti-fog coatings. Anti-reflection coatings reduce unwanted reflections from the lens surfaces and increase light transmission. Hard coatings are applied for preventing the plastic lens surface from scratches and abrasion. Hard coatings are not required for the mineral lenses due to their hardness. Clean coat makes the lens surface smooth and hydrophobic. Thus, it prevents the adherence of dust, tarnish, and dirt particles on the lens surface. Mirror coatings are applied onto the sunglasses for cosmetic purpose. Color tinted and photochromic lenses are used for sun protection and absorption of the harmful UV radiations. Anti-fog coatings make the lens surface hydrophilic and prevent the coalescence of tiny water droplets on the lens surface that reduces light transmission. (Turk J Ophthalmol 2012; 42: 359-69

  3. Tear exchange and contact lenses: a review.

    Science.gov (United States)

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  4. Software for Fermat's Principle and Lenses

    Science.gov (United States)

    Mihas, Pavlos

    2012-01-01

    Fermat's principle is considered as a unifying concept. It is usually presented erroneously as a "least time principle". In this paper we present some software that shows cases of maxima and minima and the application of Fermat's principle to the problem of focusing in lenses. (Contains 12 figures.)

  5. Gourami lenses convert tryptophan into 3-hydroxykynurenine.

    Science.gov (United States)

    Truscott, R J; Wood, A M

    1994-01-01

    Although free tryptophan was found in the lens of both the kissing gourami (Helostoma temmincki) and the 3-spot gourami (Trichogaster trichopterus), only the lens of the latter species contained 3-hydroxykynurenine. Radiolabel experiments carried out on 3-spot gourami lenses in culture demonstrated that, as in humans, lenticular tryptophan is converted to 3-hydroxykynurenine probably via the intermediate kynurenine.

  6. Processes for manufacturing multifocal diffractive-refractive intraocular lenses

    Science.gov (United States)

    Iskakov, I. A.

    2017-09-01

    Manufacturing methods and design features of modern diffractive-refractive intraocular lenses are discussed. The implantation of multifocal intraocular lenses is the most optimal method of restoring the accommodative ability of the eye after removal of the natural lens. Diffractive-refractive intraocular lenses are the most widely used implantable multifocal lenses worldwide. Existing methods for manufacturing such lenses implement various design solutions to provide the best vision function after surgery. The wide variety of available diffractive-refractive intraocular lens designs reflects the demand for this method of vision correction in clinical practice and the importance of further applied research and development of new technologies for designing improved lens models.

  7. Gravitationally lensed quasars in Gaia: I. Resolving small-separation lenses

    Science.gov (United States)

    Lemon, Cameron A.; Auger, Matthew W.; McMahon, Richard G.; Koposov, Sergey E.

    2017-12-01

    Gaia's exceptional resolution (FWHM $\\sim$ 0.1$^{\\prime\\prime}$) allows identification and cataloguing of the multiple images of gravitationally lensed quasars. We investigate a sample of 49 known lensed quasars in the SDSS footprint, with image separations less than 2$^{\\prime\\prime}$, and find that 8 are detected with multiple components in the first Gaia data release. In the case of the 41 single Gaia detections, we generally are able to distinguish these lensed quasars from single quasars when comparing Gaia flux and position measurements to those of Pan-STARRS and SDSS. This is because the multiple images of these lensed quasars are typically blended in ground-based imaging and therefore the total flux and a flux-weighted centroid are measured, which can differ significantly from the fluxes and centroids of the individual components detected by Gaia. We compare the fluxes through an empirical fit of Pan-STARRS griz photometry to the wide optical Gaia bandpass values using a sample of isolated quasars. The positional offsets are calculated from a recalibrated astrometric SDSS catalogue. Applying flux and centroid difference criteria to spectroscopically confirmed quasars, we discover 4 new sub-arcsecond-separation lensed quasar candidates which have two distinct components of similar colour in archival CFHT or HSC data. Our method based on single Gaia detections can be used to identify the $\\sim$ 1400 lensed quasars with image separation above 0.5$^{\\prime\\prime}$, expected to have only one image bright enough to be detected by Gaia.

  8. Identification of $\\tau$ leptons and Higgs boson search in the $\\mu+\\tau$ final state at the D0 experiment at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Madar, Romain [Univ. of Paris, Orsay (France)

    2011-01-01

    The gauge symmetry is the heart of our understanding of the electroweak interaction and describes all the current experimental results. However, the intrinsic incompatibility between the gauge invariance and the mass of particles leads to the introduction of a new particle, the Higgs boson, for which we have no experimental evidence as of today. This thesis describes the Higgs boson search in the μ + τ final state in 7.3 fb-1 of pp collisions at √s = 1.96 TeV collected by the DØ detector at the Tevatron. This analysis completes the golden channels (dimuons, electron-muon, dielectrons) exploiting the decay chain H → WW → ℓvℓv , which is the main Higgs boson decay mode in the mass window accessible to the Tevatron. Since the final state includes a lepton, work was done to improve their identification among jets. An increase of 15% was achieved thanks to the the following : changing tuning parameters for the identification neural network, use of the kinematical dependence of the algorithm performances, incorporation of the τ lepton life time information and full study of the additionnal information coming from the central preshower measurements. Then, since the dominant background of the μ + τ Higgs boson search is W+jets (where one jet fakes a τ ), a method was developed to obtain good modeling of this background, not provided by the default simulation. This method is based, among other things, on the charge correlation between the muon and the τ candidate which allows for calibration of this background in the data excluding the signal region. Finally, all the kinematic and/or topological differences between the signal and the background were exploited to optimize this search, reaching an (observed) expected sensitivity of 7.8 (6.6) times the Standard Model for mH = 165 GeV=c2. In addition, this result was also interpreted in a fourth fermion generation scenario. For the first time, this analysis is included in the D

  9. Bias to CMB lensing reconstruction from temperature anisotropies due to large-scale galaxy motions

    Science.gov (United States)

    Ferraro, Simone; Hill, J. Colin

    2018-01-01

    Gravitational lensing of the cosmic microwave background (CMB) is expected to be amongst the most powerful cosmological tools for ongoing and upcoming CMB experiments. In this work, we investigate a bias to CMB lensing reconstruction from temperature anisotropies due to the kinematic Sunyaev-Zel'dovich (kSZ) effect, that is, the Doppler shift of CMB photons induced by Compton scattering off moving electrons. The kSZ signal yields biases due to both its own intrinsic non-Gaussianity and its nonzero cross-correlation with the CMB lensing field (and other fields that trace the large-scale structure). This kSZ-induced bias affects both the CMB lensing autopower spectrum and its cross-correlation with low-redshift tracers. Furthermore, it cannot be removed by multifrequency foreground separation techniques because the kSZ effect preserves the blackbody spectrum of the CMB. While statistically negligible for current data sets, we show that it will be important for upcoming surveys, and failure to account for it can lead to large biases in constraints on neutrino masses or the properties of dark energy. For a stage 4 CMB experiment, the bias can be as large as ≈15 % or 12% in cross-correlation with LSST galaxy lensing convergence or galaxy overdensity maps, respectively, when the maximum temperature multipole used in the reconstruction is ℓmax=4000 , and about half of that when ℓmax=3000 . Similarly, we find that the CMB lensing autopower spectrum can be biased by up to several percent. These biases are many times larger than the expected statistical errors. We validate our analytical predictions with cosmological simulations and present the first complete estimate of secondary-induced CMB lensing biases. The predicted bias is sensitive to the small-scale gas distribution, which is affected by pressure and feedback mechanisms, thus making removal via "bias-hardened" estimators challenging. Reducing ℓmax can significantly mitigate the bias at the cost of a decrease

  10. Soft contact lenses for keratoconus: case report.

    Science.gov (United States)

    González-Méijome, José M; Jorge, Jorge; de Almeida, José B; Parafita, Manuel A

    2006-05-01

    Contact lenses have assisted the refractive correction of keratoconus since the 19th century. In these case reports, the authors describe their experience with a new soft contact lens design. The Soft K is a new soft lens comprising a thick fenestrated design to fit in patients with mild to moderate corneal distortion and fitting problems or physical intolerance to rigid gas-permeable (RGP) contact lenses. Three eyes with mild keratoconus from two 25-year-old patients (one man and one woman) were fitted with the Soft K contact lens. Both patients had previously worn other contact lens types. Improvements in comfort and quality of vision compared with previously worn RGP or soft toric contact lenses were the most remarkable advantages objectively observed and subjectively described by both patients. For one patient, a professional soccer player, the benefits were also important in terms of compatibility with the dynamic environment of his activity, satisfying the need for stable correction and constant full field-of-view demand without spectacles. No physiologic complications such as edema or neovascularization were observed during the follow-up period. This new soft lens design for irregular corneas is especially indicated for those with intolerance to RGP or other contact lenses and for patients for whom RGP lenses do not satisfy the dynamic environment inherent to some professional or leisure activities, particularly sport activity. This is a good option to consider in patients with mild to moderate keratoconus and good correction of slight or moderate irregular corneal astigmatism with good tolerance. Aftercare implications are also discussed.

  11. KeraSoft 3 contact lenses in corneal ectasia.

    Science.gov (United States)

    Uçakhan, Omür O; Bayraktutar, Betül

    2014-11-01

    To evaluate the safety, efficacy, and on-eye performance of KeraSoft 3 contact lenses (UltraVision) in ectatic corneal diseases. The charts of patients who were fit with KeraSoft 3 were reviewed. The reason for KeraSoft 3 lens fit, the number of trial lenses required for ideal fit, centration, movement, and stabilization of the contact lens, uncorrected, spectacle-corrected, and contact lens-corrected visual acuities, slitlamp biomicroscopy findings, patient comfort, and daily duration of contact lens wear were evaluated. Seventy eyes of 40 patients were fit with the KeraSoft 3 lens. Indications included rigid gas permeable (RGP) lens intolerance in 41 eyes of 24 patients (58.5%), patients' desire to use soft contact lenses in 26 eyes of 14 patients (37.1%), and proud nebula in 3 eyes of 2 patients (4.4%). The number of trial lenses required for ideal fit was 1.2±0.4 lenses. Eleven patients (20 eyes, 29%) never purchased the contact lens, 15 patients (26 eyes, 37%) discontinued after purchasing, and 14 patients (24 eyes, 34%) continued successfully wearing their lenses. In the latter group, the visual acuity improved significantly (Pcontact lenses as "very good" to "excellent," with a desire to continue wearing them. In refractive correction of corneal ectasia, KeraSoft 3 contact lenses seem to be a good alternative to RGP lenses before more sophisticated lenses such as hybrid or scleral lenses are tried.

  12. Laboratory analyses of two explanted hydrophobic acrylic intraocular lenses

    Directory of Open Access Journals (Sweden)

    Yunhai Dai

    2014-01-01

    Full Text Available Two three-piece hydrophobic acrylic intraocular lenses (IOLs were explanted from two patients at 7 and 9 years, respectively, after implantation, because of poor fundus visualisation and/or a clinically significant decrease in visual acuity related to their opacified IOLs. In addition to light microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, confocal laser scanning microscopy was used for the first time to observe the explanted IOLs. The clinical aspect seemed to correspond to the phenomenon of surface light scattering, while laboratory analyses showed dense glistenings in the central layer of the IOL optic, which had no change next to the surface. Further studies on these phenomena are needed.

  13. Electroweak corrections to monojet production at the Tevatron and the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Denner, Ansgar [Universitaet Wuerzburg, Institut fuer Theoretische Physik und Astrophysik, Wuerzburg (Germany); Dittmaier, Stefan [Albert-Ludwigs-Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Kasprzik, Tobias [Karlsruhe Institute of Technology (KIT), Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); Mueck, Alexander [RWTH Aachen University, Institut fuer Theoretische Teilchenphysik und Kosmologie, Aachen (Germany)

    2013-02-15

    Single-jet production with missing transverse momentum is one of the most promising discovery channels for new physics at the LHC. In the Standard Model, Z+jet production with a Z-boson decay into neutrinos leads to this monojet signature. To improve the corresponding Standard Model predictions, we present the calculation of the full next-to-leading-order (NLO) electroweak corrections and a recalculation of the NLO QCD corrections to monojet production at the Tevatron and the LHC. We discuss the phenomenological impact on the total cross sections as well as on relevant differential distributions. (orig.)

  14. From Tevatron's top and lepton-based asymmetries to the LHC

    CERN Document Server

    Carmona, Adrian; Falkowski, Adam; Khatibi, Sara; Najafabadi, Mojtaba Mohammadi; Perez, Gilad; Santiago, Jose

    2014-01-01

    We define a lepton-based asymmetry in semi-leptonic ttbar production at the LHC. We show that the ratio of this lepton-based asymmetry and the ttbar charge asymmetry, measured as a function of the lepton transverse momentum or the ttbar invariant mass is a robust observable in the Standard Model. It is stable against higher order corrections and mis-modeling effects. We show that this ratio can also be a powerful discriminant among different new physics models and between them and the Standard Model. Finally, we show that a related ratio defined at the Tevatron is also robust as a function of the ttbar invariant mass.

  15. QCD corrections to W boson plus heavy quark production at the Tevatron

    CERN Document Server

    Giele, W T; Laenen, Eric; Giele, Walter T; Keller, Stephane; Laenen, Eric

    1996-01-01

    The next-to-leading order QCD corrections to the production of a W-boson in association with a jet containing a heavy quark are presented. The calculation is fully differential in the final state particle momenta and includes the mass of the heavy quark. We study for the case of the Tevatron the sensitivity of the cross section to the strange quark distribution function, the dependence of the cross section on the heavy quark mass, the transverse momentum distribution of the jet containing the heavy quark, and the momentum distribution of the heavy quark in the jet.

  16. Search for chargino and neutralino at Run II of the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Canepa, Anadi [Purdue Univ., West Lafayette, IN (United States)

    2006-08-01

    In this dissertation we present a search for the associated production of charginos and neutralinos, the supersymmetric partners of the Standard Model bosons. We analyze a data sample representing 745 pb-1 of integrated luminosity collected by the CDF experiment at the p$\\bar{p}$ Tevatron collider. We compare the Standard Model predictions with the observed data selecting events with three leptons and missing transverse energy. Finding no excess, we combine the results of our search with similar analyses carried out at CDF and set an upper limit on the chargino mass in SUSY scenarios.

  17. B(s) Mixing, Delta Gamma(s) and CP Violation at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Di Giovanni, Gian Piero; /Paris U., VI-VII

    2008-05-01

    The authors discuss the results from the Tevatron experiments on mixing and CP violation in the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} system, with particular emphasis to the updated measurements of the decay-width difference {Delta}{Lambda}{sub s} and the first measurement of the CP-violating phase {beta}{sub s} using flavor tagging information. They also briefly review the charge asymmetry measurements in semileptonic B{sub s}{sup 0} decays and in B{sup {+-}} {yields} J/{psi}K{sup {+-}} decays.

  18. Microwave Schottky diagnostic systems for the Fermilab Tevatron, Recycler, and CERN LHC

    CERN Document Server

    Pasquinelli, Ralph J

    2011-01-01

    A means for non-invasive measurement of transverse and longitudinal characteristics of bunched beams in synchrotrons has been developed based on high sensitivity slotted waveguide pickups. The pickups allow for bandwidths exceeding hundreds of MHz while maintaining good beam sensitivity characteristics. Wide bandwidth is essential to allow bunch-by-bunch measurements by means of a fast gate. The Schottky detector system is installed and successfully commissioned in the Fermilab Tevatron, Recycler and CERN LHC synchrotrons. Measurement capabilities include tune, chromaticity, and momentum spread of single or multiple beam bunches in any combination. With appropriate calibrations, emittance can also be measured by integrating the area under the incoherent tune sidebands.

  19. Model Independent Searches for New Physics at the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Piper, Joel

    2009-06-01

    The standard model is a successful but limited theory. There is significant theoretical motivation to believe that new physics may appear at the energy scale of a few TeV, the lower end of which is currently probed by the Fermilab Tevatron Collider. The methods used to search for physics beyond the standard model in a model independent way and the results of theses searches based on 1.0 fb{sup -1} of data collected with the D0 detector and 2.0 fb{sup -1} at the CDF detector are presented.

  20. J/{sub psi} production: Tevatron and fixed-target collisions

    Energy Technology Data Exchange (ETDEWEB)

    Petrelli, A.

    2000-06-01

    In this talk the author shows the results of a fit of the NRQCD matrix elements to the CDF data for direct J/{psi} production, by including the radiative corrections to the g g {r_arrow} {sup 3} S {sub 1}{sup [1]} channel and the effect of the k{sub T}-smearing. Furthermore he performs the NLO NRQCD analysis of J/{psi} production in fixed-target proton-nucleon collisions and he fits the colour-octet matrix elements to the available experimental data. The results are compared to the Tevatron ones.

  1. E710, $p\\bar{p}$ Elastic Scattering at Tevatron Energies

    Energy Technology Data Exchange (ETDEWEB)

    Sadr, Sasan [Northwestern Univ., Evanston, IL (United States)

    1993-11-01

    Experiment E710, located at site EO of the Tevatron collider at Fermilab, was conceived in order to measure $p\\bar{p}$ elastic scattering. The measured parameters were: the total cross section $\\sigma_t$, the ratio of the real to the imaginary part of the forward scattering amplitude $p$, the nuclear slope parameter B, the nuclear curvature parameter C, the total elastic cross section $\\sigma_{el}$, and the single diffractive cross section $\\sigma_{sd}$. These measurements were taken at center-of-mass energies of $\\sqrt{s}$= 1.02 and 1.8 TeV.

  2. Review of Physics Results from the Tevatron: Searches for New Particles and Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Toback, David [Texas A-M; ŽIvković, Lidija [Belgrade U.

    2015-02-17

    We present a summary of results for searches for new particles and interactions at the Fermilab Tevatron collider by the CDF and the D0 experiments. These include results from Run I as well as Run II for the time period up to July 2014. We focus on searches for supersymmetry, as well as other models of new physics such as new fermions and bosons, various models of excited fermions, leptoquarks, technicolor, hidden-valley model particles, long-lived particles, extra dimensions, dark matter particles, and signature-based searches.

  3. Measurements of the masses, lifetimes and decay modes of hadrons at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Dorigo, Mirco; /Trieste U. /INFN, Trieste

    2010-05-01

    The Tevatron provides 1.96 TeV p{bar p} collisions and allows for collection of rich b-hadron samples to the two experiments CDF and D0. The study of heavy flavor properties represents a fruitful opportunity to investigate the flavor sector of the Standard Model (SM) and to look for hints of New Physics (NP). Here we report the first measurement of polarization amplitudes in B{sub s}{sup 0} charmless decays, world leading results on b-hadron lifetimes, and measurements of several other properties of b-hadrons.

  4. Tevatron Beam Lifetimes at Injection Using the Shot Data Analysis System

    CERN Document Server

    Xiao, Aimin; Lebrun, Paul; McCrory, Elliott; Papadimitriou, Vaia; Slaughter, Anna Jean

    2005-01-01

    The purpose of the Shot Data Acquisition and Analysis (SDA) system is to provide summary data on the Fermilab RunII accelerator complex and provide related software for detailed analyses. In this paper, we discuss such a specific analysis on Tevatron beam lifetimes at injection. These results are based on SDA data, tools and methodology. Beam lifetime is one of our most important diagnostics. An analysis of it can give information on intra beam scattering, aperture limitations, instabilities and most importantly beam-beam effects. Such an analysis gives us a better understanding of our machine, and will lead to an improved performance in the future.

  5. Fragmentation contributions to J/ψ production at the Tevatron and the LHC.

    Science.gov (United States)

    Bodwin, Geoffrey T; Chung, Hee Sok; Kim, U-Rae; Lee, Jungil

    2014-07-11

    We compute leading-power fragmentation corrections to J/ψ production at the Tevatron and the LHC. We find that, when these corrections are combined with perturbative corrections through next-to-leading order in the strong coupling constant α(s), we obtain a good fit to high-p(T) cross section data from the CDF and CMS Collaborations. The fitted long-distance matrix elements lead to predictions of near-zero J/ψ polarization in the helicity frame at large p(T).

  6. Factorization breaking in high-transverse-momentum charged-hadron production at the Tevatron?

    Science.gov (United States)

    Albino, S; Kniehl, B A; Kramer, G

    2010-06-18

    We compare the transverse-momentum (pT) distribution of inclusive light-charged-particle production measured by the CDF Collaboration at the Fermilab Tevatron with the theoretical prediction evaluated at next-to-leading order in quantum chromodynamics using fragmentation functions recently determined through a global data fit. While in the lower pT range the data agree with the prediction within the theoretical error or slightly undershoot it, they significantly exceed it in the upper pT range, by several orders of magnitude at the largest values of pT, potentially challenging the factorization theorem.

  7. First measurement of the W boson mass in run II of the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, T.; Abulencia, A.; /Helsinki Inst. of Phys.; Adelman, J.; /Illinois U., Urbana; Affolder, Anthony Allen; /Chicago U., EFI; Akimoto, T.; /UC, Santa Barbara; Albrow, Michael G.; /Tsukuba U.; Amerio, S.; /Fermilab; Amidei, Dante E.; /Padua U.; Anastassov, A.; /Michigan U.; Anikeev, K.; /Rutgers U., Piscataway; Annovi, A.; /Fermilab /Frascati /Comenius U.

    2007-07-01

    We present a measurement of the W boson mass using 200 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV by the CDF II detector at Run II of the Fermilab Tevatron. With a sample of 63964 W {yields} ev candidates and 51128 W W {yields} {mu}v candidates, we measure M{sub W} = (80413 {+-} 34{sub stat} {+-}34{sub syst} = 80413 {+-} 48) MeV/c{sup 2}. This is the most precise single measurement of the W boson mass to date.

  8. Jet Substructure at the Tevatron and LHC: New results, new tools, new benchmarks

    CERN Document Server

    Altheimer, A; Asquith, L; Brooijmans, G; Butterworth, J; Campanelli, M; Chapleau, B; Cholakian, A E; Chou, J P; Dasgupta, M; Davison, A; Dolen, J; Ellis, S D; Essig, R; Fan, J J; Field, R; Fregoso, A; Gallicchio, J; Gershtein, Y; Gomes, A; Haas, A; Halkiadakis, E; Halyo, V; Hoeche, S; Hook, A; Hornig, A; Huang, P; Izaguirre, E; Jankowiak, M; Kribs, G; Krohn, D; Larkoski, A J; Lath, A; Lee, C; Lee, S J; Loch, P; Maksimovic, P; Martinez, M; Miller, D W; Plehn, T; Prokofiev, K; Rahmat, R; Rappoccio, S; Safonov, A; Salam, G P; Schumann, S; Schwartz, M D; Schwartzman, A; Seymour, M; Shao, J; Sinervo, P; Son, M; Soper, D E; Spannowsky, M; Stewart, I W; Strassler, M; Strauss, E; Takeuchi, M; Thaler, J; Thomas, S; Tweedie, B; Vasquez Sierra, R; Vermilion, C K; Villaplana, M; Vos, M; Wacker, J; Walker, D; Walsh, J R; Wang, L-T; Wilbur, S; Yavin, I; Zhu, W

    2012-01-01

    In this report we review recent theoretical progress and the latest experimental results in jet substructure from the Tevatron and the LHC. We review the status of and outlook for calculation and simulation tools for studying jet substructure. Following up on the report of the Boost 2010 workshop, we present a new set of benchmark comparisons of substructure techniques, focusing on the set of variables and grooming methods that are collectively known as "top taggers". To facilitate further exploration, we have attempted to collect, harmonise, and publish software implementations of these techniques.

  9. Microwave Schottky diagnostic systems for the Fermilab Tevatron, Recycler, and CERN Large Hadron Collider

    Directory of Open Access Journals (Sweden)

    Ralph J. Pasquinelli

    2011-07-01

    Full Text Available A means for noninvasive measurement of transverse and longitudinal characteristics of bunched beams in synchrotrons has been developed based on high sensitivity slotted waveguide pickups. The pickups allow for bandwidths exceeding hundreds of MHz while maintaining good beam sensitivity characteristics. Wide bandwidth is essential to allow bunch-by-bunch measurements by means of a fast gate. The Schottky detector system is installed and successfully commissioned in the Fermilab Tevatron, Recycler and CERN LHC synchrotrons. Measurement capabilities include tune, chromaticity, and momentum spread of single or multiple beam bunches in any combination. With appropriate calibrations, emittance can also be measured by integrating the area under the incoherent tune sidebands.

  10. Measurement of the leptonic angular distribution in $W$ boson decay as a function of the $W$ transverse momentum using the CDF detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Cerrito, Lucio [Univ. College London, Bloomsbury (United Kingdom)

    2002-04-01

    A measurement of the angular distribution of leptons from the analysis of W-boson decay data is presented. Although the properties of the leptonic angular distribution from W decays have been studied extensively in the past decades, the amount of data collected at the Tevatron is sufficient to observe Quantum Chromo Dynamics (QCD) corrections. When QCD is included, the lepton polar-angle distribution is best described by two parameters, $\\alpha_1$ and $\\alpha_2$, functions of $p^W_T$: $\\frac{{\\rm d}\\sigma}{{\\rm d}\\cos\\theta^*} \\propto (1\\pm\\alpha_1 \\cos\\theta^* +\\alpha_2 \\cos^2\\theta^*),$ where $\\theta^*$ is measured in the W rest-frame with respect to the proton beam. Both the W asymmetry measurement and the W mass precision measurement at CDF rely on the accurate understanding and simulation of the leptonic angular distribution. The data analysed in this thesis, which include both the electron and the muon channels, were collected with the CDF detector at the Tevatron proton-antiproton collider during Run Ib (1994$-$1996). The coefficient $\\alpha_2$ of the polar-angle distribution is measured as a function of the W-boson transverse-momentum up to 100 GeV. The measurement strategy consists of fitting the transverse-mass distribution to a set of templates from a Monte Carlo event and detector simulation. A log-likelihood method is used to determine $\\alpha_2$. The measured values of $\\alpha_2$ confirm the Standard Model expectation for the W-polarisation at high transverse-momentum. A study for a measurement of $\\alpha_1$ is also presented. However, there is insufficient sensitivity for the measurement of $\\alpha_1$ with the CDF Run I detector.

  11. A Monitor of the Focusing Strength of Plasma Lenses Using MeV Synchrotron Radiation

    CERN Document Server

    Field, C; Ng, J S T; Field, Clive; Mazaheri, Gholam; Ng, Johnny S.T.

    2002-01-01

    The focusing strength of plasma lenses used with high energy electron or positron beams can give rise to synchrotron radiation with critical energies in the MeV range. A method is described for measuring the characteristic energy of this radiation as a way of monitoring the strength of the focus. The principle has been implemented in a plasma lens experiment with a 28.5 GeV positron beam.

  12. Multiple Parton Interactions in p$bar{p}$ Collisions in D0 Experiment at the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Golovanov, Georgy [Joint Inst. for Nuclear Research (JINR), Dubna (Russia)

    2016-01-01

    The thesis is devoted to the study of processes with multiple parton interactions (MPI) in a ppbar collision collected by D0 detector at the Fermilab Tevatron collider at sqrt(s) = 1.96 TeV. The study includes measurements of MPI event fraction and effective cross section, a process-independent parameter related to the effective interaction region inside the nucleon. The measurements are done using events with a photon and three hadronic jets in the final state. The measured effective cross section is used to estimate background from MPI for WH production at the Tevatron energy

  13. Irregular Corneas: Improve Visual Function With Scleral Contact Lenses.

    Science.gov (United States)

    de Luis Eguileor, Beatriz; Etxebarria Ecenarro, Jaime; Santamaria Carro, Alaitz; Feijoo Lera, Raquel

    2016-10-20

    To assess visual function in patients with irregular cornea who do not tolerate gas permeable (GP) corneal contact lenses and are fitted with GP scleral contact lenses (Rose K2 XL). In this prospective study, we analyzed 15 eyes of 15 patients who did not tolerate GP corneal contact lenses and were fitted with scleral contact lenses (Rose K2 XL). We assessed visual function using visual acuity and the visual function index (VF-14); we used the VF-14 as an indicator of patient satisfaction. The measurements were taken with the optical correction used before and 1 month after the fitting of the Rose K2 XL contact lenses. We also recorded the number of hours lenses had been worn over the first month. Using Rose K2 XL contact lenses, visual acuity was 0.06±0.07 logMAR. In all cases, visual acuity had improved compared with the measurement before fitting the lenses (0.31±0.18 logMAR; P=0.001). VF-14 scores were 72.74±12.38 before fitting of the scleral lenses, and 89.31±10.87 after 1 month of lens use (P=0.003). Patients used these scleral lenses for 9.33±2.99 comfortable hours of wear. Both visual acuity and VF-14 may improve after fitting Rose K2 XL contact lenses in patients with irregular corneas. In addition, in our patients, these lenses can be worn for a longer period than GP corneal contact lenses.

  14. Regular Magnetic Black Hole Gravitational Lensing

    Science.gov (United States)

    Liang, Jun

    2017-05-01

    The Bronnikov regular magnetic black hole as a gravitational lens is studied. In nonlinear electrodynamics, photons do not follow null geodesics of background geometry, but move along null geodesics of a corresponding effective geometry. To study the Bronnikov regular magnetic black hole gravitational lensing in the strong deflection limit, the corresponding effective geometry should be obtained firstly. This is the most important and key step. We obtain the deflection angle in the strong deflection limit, and further calculate the angular positions and magnifications of relativistic images as well as the time delay between different relativistic images. The influence of the magnetic charge on the black hole gravitational lensing is also discussed. Supported by the Natural Science Foundation of Education Department of Shannxi Province under Grant No 15JK1077, and the Doctorial Scientific Research Starting Fund of Shannxi University of Science and Technology under Grant No BJ12-02.

  15. Design considerations for liquid crystal contact lenses

    Science.gov (United States)

    Bailey, J.; Kaur, S.; Morgan, P. B.; Gleeson, H. F.; Clamp, J. H.; Jones, J. C.

    2017-12-01

    Switchable liquid crystal contact lenses with electrically controllable focal powers have previously been investigated as an alternative to bifocal contact lenses and spectacles for the correction of presbyopia. The simplest lens design uses a meniscus shaped cavity within the lens to contain the liquid crystal. The design of such a lens is considered in detail, including the nematic alignment and electrodes materials. The organic transparent conductor PEDOT:PSS was used as both electrode and planar alignment. Four different configurations are considered, using both planar and homeotropic orientations with either homogenous or axial alignment. Controllable switching of the focal power was demonstrated for each mode and focal power changes of up to ΔP  =  3.3  ±  0.2 D achieved. Such lens designs offer significant potential for a novel form of correction for this common visual problem.

  16. Gravitational lensing by a Horndeski black hole

    Science.gov (United States)

    Badía, Javier; Eiroa, Ernesto F.

    2017-11-01

    In this article we study gravitational lensing by non-rotating and asymptotically flat black holes in Horndeski theory. By adopting the strong deflection limit, we calculate the deflection angle, from which we obtain the positions and the magnifications of the relativistic images. We compare our results with those corresponding to black holes in General Relativity. We analyze the astrophysical consequences in the case of the nearest supermassive black holes.

  17. Fitting gravitational lenses: truth or delusion

    Science.gov (United States)

    Evans, N. Wyn; Witt, Hans J.

    2003-11-01

    The observables in a strong gravitational lens are usually just the image positions and sometimes the flux ratios. We develop a new and simple algorithm which allows a set of models to be fitted exactly to the observations. Taking our cue from the strong body of evidence that early-type galaxies are close to isothermal, we assume that the lens is scale-free with a flat rotation curve. External shear can be easily included. Our algorithm allows full flexibility regarding the angular structure of the lensing potential. Importantly, all the free parameters enter linearly into the model and so the lens and flux ratio equations can always be solved by straightforward matrix inversion. The models are only restricted by the fact that the surface mass density must be positive. We use this new algorithm to examine some of the claims made for anomalous flux ratios. It has been argued that such anomalies betray the presence of substantial amounts of substructure in the lensing galaxy. We demonstrate by explicit construction that some of the lens systems for which substructure has been claimed can be well fitted by smooth lens models. This is especially the case when the systematic errors in the flux ratios (caused by microlensing or differential extinction) are taken into account. However, there is certainly one system (B1422+231) for which the existing smooth models are definitely inadequate and for which substructure may be implicated. Within a few tens of kpc of the lensing galaxy centre, dynamical friction and tidal disruption are known to be very efficient at dissolving any substructure. Very little substructure is projected within the Einstein radius. The numbers of strong lenses for which substructure is currently being claimed may be so large that this contradicts rather than supports cold dark matter theories.

  18. Motivation and detectability of an invisibly-decaying Higgs boson at the Fermilab Tevatron

    CERN Document Server

    Martin, S P; Martin, Stephen P.; Wells, James D.

    1999-01-01

    A Higgs boson with mass below 150 GeV has a total decay width of less than 20 MeV into accessible Standard Model states. This narrow width means that the usual branching fractions for such a light Higgs boson are highly susceptible to any new particles to which it has unsuppressed couplings. In particular, there are many reasonable and interesting theoretical ideas that naturally imply an invisibly-decaying Higgs boson. The motivations include models with light supersymmetric neutralinos, spontaneously broken lepton number, radiatively generated neutrino masses, additional singlet scalar(s), or right-handed neutrinos in the extra dimensions of TeV gravity. We discuss these approaches to model building and their implications for Higgs boson phenomenology in future Tevatron runs. We find, for example, that the Tevatron with 30 fb^{-1} integrated luminosity can make a 3\\sigma observation in the l+ l- plus missing transverse energy channel for a 125 GeV Higgs boson that is produced with the same strength as the S...

  19. MSTW PDFs and impact of PDFs on cross sections at Tevatron and LHC

    CERN Document Server

    Watt, Graeme

    2012-01-01

    We briefly summarise the "MSTW 2008" determination of parton distribution functions (PDFs), and subsequent follow-up studies, before reviewing some topical issues concerning the PDF dependence of cross sections at the Tevatron and LHC. We update a recently published study of benchmark Standard Model total cross sections (W, Z, gg->H and t-tbar production) at the 7 TeV LHC, where we account for all publicly available PDF sets and we compare to LHC data for W, Z, and t-tbar production. We show the sensitivity of the Higgs cross sections to the gluon distribution, then we demonstrate the ability of the Tevatron jet data, and also the LHC t-tbar data, to discriminate between PDF sets with different high-x gluon distributions. We discuss the related problem of attempts to extract the strong coupling alpha_S from only deep-inelastic scattering data, and we conclude that a direct data constraint on the high-x gluon distribution is required to obtain a meaningful result. We therefore discourage the use of PDF sets ob...

  20. Search for the Standard Model Higgs boson in final states with $b$ quarks at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Potamianos, Karolos

    2011-11-01

    We present the result of searches for a low mass Standard Model Higgs boson produced in association with a W or a Z boson at a center-of-mass energy of {radical}s = 1.96 TeV with the CDF and D0 detectors at the Fermilab Tevatron collider. The search is performed in events containing one or two b tagged jets in association with either two leptons, or one lepton and an imbalance in transverse energy, or simply a large imbalance in transverse energy. Datasets corresponding to up to 8.5 fb{sup -1} of integrated luminosity are considered in the analyses. These are the most powerful channels in the search for a low mass Higgs boson at the Tevatron. Recent sensitivity improvements are discussed. For a Higgs mass of 115 GeV/c{sup 2}, the expected sensitivity for the most sensitive individual analyses reaches 2.3 times the SM prediction at 95% confidence level (C.L.), with all limits below 5 times the SM. Additionally, a WZ/ZZ cross-section measurement is performed to validate the analysis techniques deployed for searching for the Higgs.

  1. The Reach of the Fermilab Tevatron and CERN LHC for Gaugino Mediated SUSY Breaking Models

    CERN Document Server

    Baer, Howard W; Krupovnickas, T; Tata, Xerxes; Baer, Howard; Belyaev, Alexander; Krupovnickas, Tadas; Tata, Xerxes

    2002-01-01

    In supersymmetric models with gaugino mediated SUSY breaking (inoMSB), it is assumed that SUSY breaking on a hidden brane is communicated to the visible brane via gauge superfields which propagate in the bulk. This leads to GUT models where the common gaugino mass $m_{1/2}$ is the only soft SUSY breaking term to receive contributions at tree level. To obtain a viable phenomenology, it is assumed that the gaugino mass is induced at some scale $M_c$ beyond the GUT scale, and that additional renormalization group running takes place between $M_c$ and $M_{GUT}$ as in a SUSY GUT. We assume an SU(5) SUSY GUT above the GUT scale, and compute the SUSY particle spectrum expected in models with inoMSB. We use the Monte Carlo program ISAJET to simulate signals within the inoMSB model, and compute the SUSY reach including cuts and triggers approriate to Fermilab Tevatron and CERN LHC experiments. We find no reach for SUSY by the Tevatron collider in the trilepton channel. %either with or without %identified tau leptons. ...

  2. Reach of the Fermilab Tevatron and CERN LHC for gaugino mediated SUSY breaking models

    CERN Document Server

    Baer, Howard W; Krupovnickas, T; Tata, Xerxes; 10.1103/PhysRevD.65.075024

    2002-01-01

    In supersymmetric models with gaugino mediated SUSY breaking (gMSB), it is assumed that SUSY breaking on a hidden brane is communicated to the visible brane via gauge superfields which propagate in the bulk. This leads to GUT models where the common gaugino mass m/sub 1/2/ is the only soft SUSY breaking term to receive contributions at the tree level. To obtain a viable phenomenology, it is assumed that the gaugino mass is induced at some scale M/sub c/ beyond the GUT scale, and that additional renormalization group running takes place between M/sub c/ and M/sub GUT/ as in a SUSY GUT. We assume an SU(5) SUSY GUT above the GUT scale, and compute the SUSY particle spectrum expected in models with gMSB. We use the Monte Carlo program ISAJET to simulate signals within the gMSB model, and compute the SUSY reach including cuts and triggers appropriate to Fermilab Tevatron and CERN LHC experiments. We find no reach for SUSY by the Tevatron collider in the trilepton channel. At the CERN LHC, values of m/sub 1/2/=1000...

  3. Channeling and Volume Reflection Based Crystal Collimation of Tevatron Circulating Beam Halo

    CERN Document Server

    Shiltsev, V.; Drozhdin, A.; Johnson, T.; Legan, A.; Mokhov, N.; Reilly, R.; Still, D.; Tesarek, R.; Zagel, J.; Peggs, S.; Assmann, R.; Previtali, V.; Scandale, W.; Chesnokov, Y.; Yazynin, I.; Guidi, V.; Ivanov, Y.

    2010-01-01

    The T980 crystal collimation experiment is underway at the Tevatron to determine if this technique could increase 980 GeV beam-halo collimation efficiency at high-energy hadron colliders such as the Tevatron and the LHC. T980 also studies various crystal types and parameters. The setup has been substantially enhanced during the Summer 2009 shutdown by installing a new O-shaped crystal in the horizontal goniometer, as well as adding a vertical goniometer with two alternating crystals (O-shaped and multi-strip) and additional beam diagnostics. First measurements with the new system are quite encouraging, with channeled and volume-reflected beams observed on the secondary collimators as predicted. Investigation of crystal collimation efficiencies with crystals in volume reflection and channeling modes are described in comparison with an amorphous primary collimator. Results on the system performance are presented for the end-of-store studies and for entire collider stores. The first investigation of colliding be...

  4. Non-perturbative QCD Effects and the Top Mass at the Tevatron

    CERN Document Server

    Wicke, Daniel

    2008-01-01

    The modelling of non-perturbative effects is an important part of modern collider physics simulations. In hadron collisions there is some indication that the modelling of the interactions of the beam remnants, the underlying event, may require non-trivial colour reconnection effects to be present. We recently introduced a universally applicable toy model of such reconnections, based on hadronising strings. This model, which has one free parameter, has been implemented in the Pythia event generator. We then considered several parameter sets (`tunes'), constrained by fits to Tevatron minimum-bias data, and determined the sensitivity of a simplified top mass analysis to these effects, in exclusive semi-leptonic top events at the Tevatron. A first attempt at isolating the genuine non-perturbative effects gave an estimate of order +-0.5GeV from non-perturbative uncertainties. The results presented here are an update to the original study and include recent bug fixes of Pythia that influenced the tunings investigat...

  5. Study of Long-range Collisions and Wire Compensation for Tevatron Run-II

    CERN Document Server

    Zimmermann, Frank; Erdelyi, B; Boocha, V

    2004-01-01

    This report summarizes studies of long-range collisions and their compensation by current carrying wires for the Tevatron Run-II, which were performed during a two-week stay at Fermilab, February 22 to March 8, 2004. The weak-strong code WSDIFF was significantly extended to simulate the actual long-range encounters at the Tevatron for different antiproton bunches in the train at injection and in collision. Tune footprints and diffusive apertures simulated by this code are presented for various cases, differing in the bunch position, the energy, the number of long-range and head-on collisions, the presence of additional compensating wires and the momentum deviation. It is confirmed that the solution of 4 wires for injection, previously found by B. Erdelyi, raises the dynamic aperture, by about 1.0-1.5sigma. For both injection and collision an ideal compensation of the 6 or 3 closest long-range encounters was modeled, by removing these collisions altogether. At collision, an improvement in the dynamic aperture ...

  6. Turning Gravitationally Lensed Supernovae into Cosmological Probes

    Science.gov (United States)

    Roberts-Pierel, Justin

    2017-08-01

    Recent HST observations have been critically important for twolandmark discoveries of gravitationally lensed supernovae: the firstmultiply-imaged SN, Refsdal, and the first Type Ia SN resolved intomultiple images, SN iPTF16geu. Fitting the multiple light curves ofsuch objects can deliver measurements of the lensing time delays,which in turn provide precise tests of lens models or uniqueconstraints on the Hubble constant and other cosmological parameters.For both of these SNe, initial constraints on the time delays havebeen limited by the need to account for subtle microlensingeffects. We will perform a complete reanalysis of both SN Refsdal andSN iPTF16geu, in order to refine estimates of their lensingmagnifications and time delays. Our work will improve upon previousefforts by revising the data processing and photometry, and includingthe significant yet previously ignored effects ofmicrolensing. Additionally, we will develop a publicly availablesoftware package in the course of this work, optimized specificallyfor multiply-imaged SNe. This software will be an important tool inthe next decade, supporting precise time delay measurements of tens tohundreds of lensed SNe to be found with LSST and WFIRST.

  7. Automation Enhancement of Multilayer Laue Lenses

    Energy Technology Data Exchange (ETDEWEB)

    Lauer K. R.; Conley R.

    2010-12-01

    X-ray optics fabrication at Brookhaven National Laboratory has been facilitated by a new, state of the art magnetron sputtering physical deposition system. With its nine magnetron sputtering cathodes and substrate carrier that moves on a linear rail via a UHV brushless linear servo motor, the system is capable of accurately depositing the many thousands of layers necessary for multilayer Laue lenses. I have engineered a versatile and automated control program from scratch for the base system and many subsystems. Its main features include a custom scripting language, a fully customizable graphical user interface, wireless and remote control, and a terminal-based interface. This control system has already been successfully used in the creation of many types of x-ray optics, including several thousand layer multilayer Laue lenses.Before reaching the point at which a deposition can be run, stencil-like masks for the sputtering cathodes must be created to ensure the proper distribution of sputtered atoms. Quality of multilayer Laue lenses can also be difficult to measure, given the size of the thin film layers. I employ my knowledge of software and algorithms to further ease these previously painstaking processes with custom programs. Additionally, I will give an overview of an x-ray optic simulator package I helped develop during the summer of 2010. In the interest of keeping my software free and open, I have worked mostly with the multiplatform Python and the PyQt application framework, utilizing C and C++ where necessary.

  8. 21 CFR 801.410 - Use of impact-resistant lenses in eyeglasses and sunglasses.

    Science.gov (United States)

    2010-04-01

    ... frequency of eye injuries resulting from the shattering of ordinary crown glass lenses indicates that the... thereof to the patient. (2) The physician or optometrist shall have the option of ordering glass lenses, plastic lenses, or laminated glass lenses made impact resistant by any method; however, all such lenses...

  9. Electronic liquid crystal contact lenses for the correction of presbyopia

    National Research Council Canada - National Science Library

    Milton, Harry E; Morgan, Philip B; Clamp, John H; Gleeson, Helen F

    2014-01-01

    Presbyopia, the age-related reduction in near vision acuity, is one of the leading issues facing the contact lens industry due to an increasingly ageing population and limitations associated with existing designs...

  10. Experimental Study of W Z Intermediate Bosons Associated Production with the CDF Experiment at the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Pozzobon, Nicola; /Pisa U.

    2007-09-01

    Studying WZ associated production at the Fermilab Tevatron Collider is of great importance for two main reasons. On the one hand, this process would be sensitive to anomalies in the triple gauge couplings such that any deviation from the value predicted by the Standard Model would be indicative of new physics. In addition, by choosing to focus on the final state where the Z boson decays to b{bar b} pairs, the event topology would be the same as expected for associated production of a W and a Standard Model light Higgs boson (m{sub H} {approx}< 135 GeV) which decays into b{bar b} pairs most of times. The process WH {yields} W b{bar b} has an expected {sigma} {center_dot} B about five times lower than WZ {yields} Wb{bar b} for m{sub H} {approx_equal} 120 GeV. Therefore, observing this process would be a benchmark for an even more difficult search aiming at discovering the light Higgs in the WH {yields} Wb{bar b} process. After so many years of Tevatron operation only a weak WZ signal was recently observed in the full leptonic decay channel, which suffers from much less competition from background. Searching for the Z in the b{bar b} decay channel in this process is clearly a very challenging endeavour. In the work described in this thesis, WZ production is searched for in a final state where the W decays leptonically to an electron-neutrino pair or a muon-neutrino pair, with associated production of a jet pair consistent with Z decays. A set of candidate events is obtained by applying appropriate cuts to the parameters of events collected by wide acceptance leptonic triggers. To improve the signal fraction of the selected events, an algorithm was used to tag b-flavored jets by means of their content of long lived b-hadrons and corrections were developed to the jet algorithm to improve the b-jet energy resolution for a better reconstruction of the Z mass. In order to sense the presence of a signal one needs to estimate the amount of background. The relative content of

  11. [Current care and maintenance systems for contact lenses].

    Science.gov (United States)

    Lipener, César; Ray, Camila Baracat Mendina

    2008-01-01

    The proper maintenance of contact lenses is crucial for their success and to maintain the continuity of their use. Many patients abandon the use of their lenses due to problems that could be solved with relatively simple treatments. The misuse of lenses, coupled with poor adjustment, contamination, eye disease and environmental factors may increase the number of corneal infections through the proliferation of microorganisms. This article aims to provide contact lens care and maintenance updates.

  12. AEROMEDICAL ASPECTS OF CONTACT LENSES (SOFT AND SEMISOFT)

    OpenAIRE

    PRASAD, GKG; VYAWAHARE, MK; KAPUR, R; SACHDEV, VS

    1995-01-01

    A comprehensive clinical study on the effects of various aviation stresses on soft and semisoft contact lenses was carried out to find out their compatibility in aviation environment. Twenty subjects (11 aircrew and 9 non air-crew) participated in the study. Twelve of them were given soft lenses of water contents of 38%, 50% and 78% and rest 8 were given semisoft lenses of daily wear and extended wear type. The environmental trial consisted of exposure to hypoxia, rapid decompression, acceler...

  13. Do swimming goggles limit microbial contamination of contact lenses?

    Science.gov (United States)

    Wu, Yvonne T; Tran, Jess; Truong, Michelle; Harmis, Najat; Zhu, Hua; Stapleton, Fiona

    2011-04-01

    Wearing goggles over contact lenses while swimming is often recommended by eye care professionals. Limited data are available to assess this recommendation. The purpose of this study was to examine whether wearing goggles while swimming limits bacterial colonization on contact lenses and whether the type of lens worn affects contamination rates. Twenty-three subjects underwent two swimming sessions at an ocean (salt water) pool (Maroubra beach Rock Pool, Sydney, Australia). Silicone hydrogel (Ciba Focus Night and Day) or hydrogel lenses (Ciba Focus Daily) were inserted into subjects' eyes before 30 min of swimming sessions, and subjects used modified goggles to mimic goggled and non-goggled conditions. At the end of each session, lenses were collected for microbial investigation. Viable bacterial colonies were classified as gram positive and gram negative and enumerated. The level of bacterial colonization on contact lenses between goggled and non-goggled conditions and between the two lens materials were compared. The range of colony forming units recovered from goggled lenses were 0 to 930 compared with 0 to 1210 on non-goggled lenses. The majority of subjects (16/23) had more microorganisms in the non-goggled condition than when wearing goggles (p = 0.03). Gram negative organisms were found in three non-goggled lenses. No significant difference was shown in the number of bacteria isolated from silicone hydrogel and hydrogel lenses (p > 0.6) irrespective of wearing goggles. Water samples had consistently higher numbers of bacterial counts than those adhered to the lenses; however, no association was found between the number of bacteria in the water sample and those found on the contact lenses. Consistently, fewer bacterial colonies were found on the goggled contact lens, thus suggesting goggles offer some protection against bacterial colonization of contact lenses while swimming. These data would support the recommendation encouraging lens wearers to use goggles

  14. Phosphorylcholine and phosphorylethanolamine in human and rhesus monkey lenses.

    Science.gov (United States)

    Jernigan, H M; Zigler, J S

    1989-11-01

    Phosphorylcholine (P-choline) and phosphorylethanolamine (P-ethanolamine) are important precursors of phospholipids. The metabolism and concentration of P-choline has been shown to change in animal models of cataract, especially in oxidatively or osmotically stressed rat lenses. The concentrations of P-choline and P-ethanolamine were determined in monkey lenses and in normal and cataractous human lenses, and the rate of synthesis of P-choline was determined in human and monkey lenses. The concentration of P-choline in 53 clear human lenses was 0.94 mM (+/- 0.31 S.D.) and was relatively unaffected by age, eye bank storage, or freezing. There was a 70% decrease in P-choline in brown cataracts but no significant change from normal in non-brown cataracts. The concentration of P-ethanolamine in human lenses was 0.45 mM (+/- 0.26 S.D.), and it appeared to decrease during frozen storage of lenses and in cataracts. The concentrations of P-choline and P-ethanolamine in 12 rhesus monkey lenses were 1.51 mM (+/- 0.27 S.D.) and 0.75 mM (+/- 0.14 S.D.), respectively. The rate of synthesis of P-choline in monkey lenses incubated with [3H]choline was 8 nmol hr-1 g-1 wet weight in 1 mM choline. Adult human lenses incubated in 1 mM choline synthesized P-choline at a rate of 23 nmol hr-1 g-1 (+/- 6 S.D.). This limited capacity for P-choline synthesis in primate lenses may contribute to the lower P-choline concentration relative to rat lenses, which contain 11 mM P-choline and can synthesize P-choline at an apparent maximum rate of 130 nmol hr-1 g-1.

  15. Use of SoftPerm contact lenses when rigid gas permeable lenses fail.

    Science.gov (United States)

    Chung, C W; Santim, R; Heng, W J; Cohen, E J

    2001-10-01

    We evaluated the performance of the SoftPerm contact lens (Wesley Jessen) in patients with irregular astigmatism, usually due to keratoconus or after penetrating keratoplasty (PK), who were unable to befitwith, or intolerant of, rigid gas permeable (RGP) contact lenses. A retrospective study of patients fit with SoftPerm lenses in the Cornea Department at Wills Eye Hospital between March 1985 and March 2000 was performed. Thirty-five cases were reviewed, with follow-up available in 33 cases. Most of the eyes had irregular astigmatism secondary to keratoconus (22/35,62.9%) or PK (10/35,28.6%) and had failed a trial of RGP lenses. The mean logMAR visual acuity with SoftPerm lenses was 0.13+/-0.18 (range -0.12 to 0.6). In 25 cases in which comparison with glasses or RGP lenses was possible, SoftPerm lenses provided better visual acuity than glasses in 17/25 cases (68%) with a mean difference of -0.24 (P = 0.001, paired t-test); visual acuity with SoftPerm lenses was better than RGP visual acuity in 13/25 cases (52%), with a mean difference of -0.06 (P = 0.07, paired t-test). Complications included broken lenses (16/33,48.5%), giant papillary conjunctivitis (GPC) (9/33, 27.3%), and peripheral corneal neovascularization (9/33, 27.3%). The GPC and peripheral corneal neovascularization were often delayed in presentation. The major subjective complaint was discomfort (13/33, 39.4%). At the last follow-up, the SoftPerm lens was still in use in 22/33 cases (66.7%). Discomfort was the most common reason for discontinuation. The mean duration of lens wear was 52.5+/-31.7 months, range 3 to 110 months. The SoftPerm lens can provide satisfactory visual correction in many cases of irregular astigmatism with RGP failure. However, problems such as frequent breakage, GPC, peripheral corneal neovascularization, and discomfort necessitate close follow-up.

  16. UV solid state laser ablation of intraocular lenses

    Science.gov (United States)

    Apostolopoulos, A.; Lagiou, D. P.; Evangelatos, Ch.; Spyratou, E.; Bacharis, C.; Makropoulou, M.; Serafetinides, A. A.

    2013-06-01

    Commercially available intraocular lenses (IOLs) are manufactured from silicone and acrylic, both rigid (e.g. PMMA) and foldable (hydrophobic or hydrophilic acrylic biomaterials), behaving different mechanical and optical properties. Recently, the use of apodizing technology to design new diffractive-refractive multifocals improved the refractive outcome of these intraocular lenses, providing good distant and near vision. There is also a major ongoing effort to refine laser refractive surgery to correct other defects besides conventional refractive errors. Using phakic IOLs to treat high myopia potentially provides better predictability and optical quality than corneal-based refractive surgery. The aim of this work was to investigate the effect of laser ablation on IOL surface shaping, by drilling circular arrays of holes, with a homemade motorized rotation stage, and scattered holes on the polymer surface. In material science, the most popular lasers used for polymer machining are the UV lasers, and, therefore, we tried in this work the 3rd and the 5th harmonic of a Q-switched Nd:YAG laser (λ=355 nm and λ=213 nm respectively). The morphology of the ablated IOL surface was examined with a scanning electron microscope (SEM, Fei - Innova Nanoscope) at various laser parameters. Quantitative measurements were performed with a contact profilometer (Dektak-150), in which a mechanical stylus scanned across the surface of gold-coated IOLs (after SEM imaging) to measure variations in surface height and, finally, the ablation rates were also mathematically simulated for depicting the possible laser ablation mechanism(s). The experimental results and the theoretical modelling of UV laser interaction with polymeric IOLs are discussed in relation with the physical (optical, mechanical and thermal) properties of the material, in addition to laser radiation parameters (laser energy fluence, number of pulses). The qualitative aspects of laser ablation at λ=213 nm reveal a

  17. Quantitative evaluation of performance of three-dimensional printed lenses

    Science.gov (United States)

    Gawedzinski, John; Pawlowski, Michal E.; Tkaczyk, Tomasz S.

    2017-08-01

    We present an analysis of the shape, surface quality, and imaging capabilities of custom three-dimensional (3-D) printed lenses. 3-D printing technology enables lens prototypes to be fabricated without restrictions on surface geometry. Thus, spherical, aspherical, and rotationally nonsymmetric lenses can be manufactured in an integrated production process. This technique serves as a noteworthy alternative to multistage, labor-intensive, abrasive processes, such as grinding, polishing, and diamond turning. Here, we evaluate the quality of lenses fabricated by Luxexcel using patented Printoptical©; technology that is based on an inkjet printing technique by comparing them to lenses made with traditional glass processing technologies (grinding, polishing, etc.). The surface geometry and roughness of the lenses were evaluated using white-light and Fizeau interferometers. We have compared peak-to-valley wavefront deviation, root mean square (RMS) wavefront error, radii of curvature, and the arithmetic roughness average (Ra) profile of plastic and glass lenses. In addition, the imaging performance of selected pairs of lenses was tested using 1951 USAF resolution target. The results indicate performance of 3-D printed optics that could be manufactured with surface roughness comparable to that of injection molded lenses (Ra<20 nm). The RMS wavefront error of 3-D printed prototypes was at a minimum 18.8 times larger than equivalent glass prototypes for a lens with a 12.7 mm clear aperture, but, when measured within 63% of its clear aperture, the 3-D printed components' RMS wavefront error was comparable to glass lenses.

  18. Contact lenses fitting after intracorneal ring segments implantation in keratoconus.

    Science.gov (United States)

    Moreira, Luciane Bugmann; Bardal, Ricardo Augustho Canto; Crisigiovanni, Leila Roberta

    2013-01-01

    Evaluate contact lenses fitting after intracorneal ring implantation for keratoconus, its visual acuity and comfort. Retrospective study of patients undergoing contact lenses fitting, after intracorneal ring for keratoconus. The criterion for contact lens fitting was unsatisfactory visual acuity with spectacle correction as referred by the patients. All patients were intolerants to contact lenses prior to intracorneal implantation. Visual acuity analysis was done by conversion of Snellen to logMAR scales. The comfort was evaluated according subjective questioning of good, medium or poor comfort. Nineteen patients were included in the study. Two patients (10.5%) did not achieved good comfort with contact lenses and underwent penetrating keratoplasties. All the others 17 patients showed good or medium comfort. Four rigid gas-permeable contact lenses were fitted, one piggyback approach, 3 toric soft contact lenses, 2 soft lenses specially design for keratoconus and 7 disposable soft lenses. The average visual acuity improved from 0.77 ± 0.37 to 0.19 ± 0.13 logMAR units after contact lenses fitting. Contact lens fitting after intracorneal ring is possible, provides good comfort, improves visual acuity, and therefore, may postpone the need for penetrating keratoplasty.

  19. Search for supersymmetric Higgs bosons in the D0 experiment at the Tevatron; Recherche de bosons de Higgs supersymetriques au Tevatron dans l'experience D0

    Energy Technology Data Exchange (ETDEWEB)

    Michaut, M

    2006-09-15

    A search for the neutral Higgs bosons of the minimal supersymmetric extension of the standard model is performed in the 3 or 4 jets channels, pp-bar {yields} {phi}({yields} bb-bar)b(b-bar) with {phi} = h, H or A. For this purpose, the data collected with the D0 detector from 2002 to 2006 at the Tevatron hadronic collider with a center of mass energy of 1.96 TeV are analyzed. A complete study of the triggering is first done. The triggering conditions are optimized in order to keep the more signal fraction possible. Furthermore, a method is developed to predict the triggering efficiencies on our signal and backgrounds using only the data. Then an analysis method that allows the prediction of our background without the help of simulations is studied. No excess in events is observed in the data sample analyzed, corresponding to an integrated luminosity of 0.9 fb{sup -1}, so limits are set in the minimal supersymmetric extension of the standard model. At 95% confidence level, the following limits are found: tan({beta}) < 46 - 121 for m{sub {phi}} equals 100 - 170 GeV. (author)

  20. DeepLensing: The Use of Deep Machine Learning to Find Strong Gravitational Lenses in Astronomical Surveys

    Science.gov (United States)

    Nord, Brian

    2017-01-01

    Strong gravitational lenses have potential as very powerful probes of dark energy and cosmic structure. However, efficiently finding lenses poses a significant challenge—especially in the era of large-scale cosmological surveys. I will present a new application of deep machine learning algorithms to find strong lenses, as well as the strong lens discovery program of the Dark Energy Survey (DES).Strong lenses provide unique information about the evolution of distant galaxies, the nature of dark energy, and the shapes of dark matter haloes. Current and future surveys, like DES and the Large Synoptic Survey Telescope, present an opportunity to find many thousands of strong lenses, far more than have ever been discovered. By and large, searches have heretofore relied on the time-consuming effort of human scanners. Deep machine learning frameworks, like convolutional neural nets, have revolutionized the task of image recognition, and have a natural place in the processing of astronomical images, including the search for strong lenses.Over five observing seasons, which started in August 2013, DES will carry out a wide-field survey of 5000 square degrees of the Southern Galactic Cap. DES has identified nearly 200 strong lensing candidates in the first two seasons of data. We have performed spectroscopic follow-up on a subsample of these candidates at Gemini South, confirming over a dozen new strong lenses. I will present this DES discovery program, including searches and spectroscopic follow-up of galaxy-scale, cluster-scale and time-delay lensing systems.I will focus, however, on a discussion of the successful search for strong lenses using deep learning methods. In particular, we show that convolutional neural nets present a new set of tools for efficiently finding lenses, and accelerating advancements in strong lensing science.

  1. File list: DNS.Oth.05.AllAg.Lenses,_Intraocular [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.05.AllAg.Lenses,_Intraocular mm9 DNase-seq Others Lenses, Intraocular http:...//dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Oth.05.AllAg.Lenses,_Intraocular.bed ...

  2. File list: DNS.Oth.50.AllAg.Lenses,_Intraocular [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.50.AllAg.Lenses,_Intraocular mm9 DNase-seq Others Lenses, Intraocular http:...//dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Oth.50.AllAg.Lenses,_Intraocular.bed ...

  3. File list: DNS.Oth.20.AllAg.Lenses,_Intraocular [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.20.AllAg.Lenses,_Intraocular mm9 DNase-seq Others Lenses, Intraocular http:...//dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Oth.20.AllAg.Lenses,_Intraocular.bed ...

  4. File list: DNS.Oth.10.AllAg.Lenses,_Intraocular [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.10.AllAg.Lenses,_Intraocular mm9 DNase-seq Others Lenses, Intraocular http:...//dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Oth.10.AllAg.Lenses,_Intraocular.bed ...

  5. Multi-crystallin complexes exist in the water-soluble high molecular weight protein fractions of aging normal and cataractous human lenses.

    Science.gov (United States)

    Srivastava, K; Chaves, J M; Srivastava, O P; Kirk, M

    2008-10-01

    lacked beaded filament proteins. Protein complexes, held mostly via non-covalent bonding, were seen in the WS-HMW proteins of 20-year-old normal, 60- to 70-year-old normal, and 60- to 70-year-old cataractous lenses. The complexes in the normal lenses were made of alpha-, beta-, and gamma-crystallin species, beaded filament proteins (filensin and/or phakinin), and aldehyde dehydrogenase. The complexes in the age-matched cataractous lenses also contained these crystallins, and aldehyde dehydrogenase, but not the beaded filament proteins. Further, the crystallin fragments were greater in number in the cataractous lenses compared to the age-matched normal lenses. During multi-angle light scattering (MALS), the HMW proteins from cataractous lenses exhibited species with lower molecular weight range than age-matched normal lenses. The HMW protein preparations from both normal and cataractous lenses showed spherical structures on electron microscopic analysis.

  6. Wearable smart sensor systems integrated on soft contact lenses for wireless ocular diagnostics

    Science.gov (United States)

    Kim, Joohee; Kim, Minji; Lee, Mi-Sun; Kim, Kukjoo; Ji, Sangyoon; Kim, Yun-Tae; Park, Jihun; Na, Kyungmin; Bae, Kwi-Hyun; Kyun Kim, Hong; Bien, Franklin; Young Lee, Chang; Park, Jang-Ung

    2017-01-01

    Wearable contact lenses which can monitor physiological parameters have attracted substantial interests due to the capability of direct detection of biomarkers contained in body fluids. However, previously reported contact lens sensors can only monitor a single analyte at a time. Furthermore, such ocular contact lenses generally obstruct the field of vision of the subject. Here, we developed a multifunctional contact lens sensor that alleviates some of these limitations since it was developed on an actual ocular contact lens. It was also designed to monitor glucose within tears, as well as intraocular pressure using the resistance and capacitance of the electronic device. Furthermore, in-vivo and in-vitro tests using a live rabbit and bovine eyeball demonstrated its reliable operation. Our developed contact lens sensor can measure the glucose level in tear fluid and intraocular pressure simultaneously but yet independently based on different electrical responses. PMID:28447604

  7. Wearable smart sensor systems integrated on soft contact lenses for wireless ocular diagnostics

    Science.gov (United States)

    Kim, Joohee; Kim, Minji; Lee, Mi-Sun; Kim, Kukjoo; Ji, Sangyoon; Kim, Yun-Tae; Park, Jihun; Na, Kyungmin; Bae, Kwi-Hyun; Kyun Kim, Hong; Bien, Franklin; Young Lee, Chang; Park, Jang-Ung

    2017-04-01

    Wearable contact lenses which can monitor physiological parameters have attracted substantial interests due to the capability of direct detection of biomarkers contained in body fluids. However, previously reported contact lens sensors can only monitor a single analyte at a time. Furthermore, such ocular contact lenses generally obstruct the field of vision of the subject. Here, we developed a multifunctional contact lens sensor that alleviates some of these limitations since it was developed on an actual ocular contact lens. It was also designed to monitor glucose within tears, as well as intraocular pressure using the resistance and capacitance of the electronic device. Furthermore, in-vivo and in-vitro tests using a live rabbit and bovine eyeball demonstrated its reliable operation. Our developed contact lens sensor can measure the glucose level in tear fluid and intraocular pressure simultaneously but yet independently based on different electrical responses.

  8. Optical and vibrational properties of phosphorylcholine-based contact lenses-Experimental and theoretical investigations

    Science.gov (United States)

    Filipecka, Katarzyna; Miedziński, Rafał; Sitarz, Maciej; Filipecki, Jacek; Makowska-Janusik, Małgorzata

    2017-04-01

    The Raman, MIR and UV-vis spectroscopy have been used to characterize Omafilcon A material constructing the one of the Proclear family contact lenses. The Omafilcon A is hydrogel material composed of 2-hydroxyethyl methacrylate (HEMA) and 2-methacryloyloxyethyl phosphorylcholine (PC) polymers crosslinked with ethyleneglycol dimethacrylate (EGDMA). Vibrational and electronic properties of the Omafilcon A material were also investigated by quantum chemical calculations. Experimentally obtained Raman, MIR and optical spectra were compared to the theoretical ones calculated applying RHF and DFT methodology. The quantum chemical calculations were performed for isolated monomers of lenses compounds as well as for their dimers and trimers to elucidate the effect of Omafilcon A polymerization and the role of an individual components.

  9. Search for the Standard Model Higgs Boson associated with a W Boson using Matrix Element Technique in the CDF detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Barbara Alvarez [Univ. of Oviedo (Spain)

    2010-05-01

    In this thesis a direct search for the Standard Model Higgs boson production in association with a W boson at the CDF detector in the Tevatron is presented. This search contributes predominantly in the region of low mass Higgs region, when the mass of Higgs boson is less than about 135 GeV. The search is performed in a final state where the Higgs boson decays into two b quarks, and the W boson decays leptonically, to a charged lepton (it can be an electron or a muon) and a neutrino. This work is organized as follows. Chapter 2 gives an overview of the Standard Model theory of particle physics and presents the SM Higgs boson search results at LEP, and the Tevatron colliders, as well as the prospects for the SM Higgs boson searches at the LHC. The dataset used in this analysis corresponds to 4.8 fb-1 of integrated luminosity of p$\\bar{p}$ collisions at a center of mass energy of 1.96 TeV. That is the luminosity acquired between the beginning of the CDF Run II experiment, February 2002, and May 2009. The relevant aspects, for this analysis, of the Tevatron accelerator and the CDF detector are shown in Chapter 3. In Chapter 4 the particles and observables that make up the WH final state, electrons, muons, ET, and jets are presented. The CDF standard b-tagging algorithms to identify b jets, and the neural network flavor separator to distinguish them from other flavor jets are also described in Chapter 4. The main background contributions are those coming from heavy flavor production processes, such as those coming from Wbb, Wcc or Wc and tt. The signal and background signatures are discussed in Chapter 5 together with the Monte CArlo generators that have been used to simulate almost all the events used in this thesis. WH candidate events have a high-pT lepton (electron or muon), high missing transverse energy, and two or more than two jets in the final state. Chapter 6 describes the event selection applied in this analysis and the

  10. Comparative Study of Two Silicone Hydrogel Contact Lenses used as Bandage Contact Lenses after Photorefractive Keratectomy.

    Science.gov (United States)

    Razmjoo, Hasan; Abdi, Elham; Atashkadi, Sayna; Reza, Akhlaghi M; Reza, Peyman A; Akbari, Mojtaba

    2012-10-01

    Silicon hydrogel bandage contact lenses are used to enhance epithelial healing, control surface-generated pain, and prevent epithelial erosions after refractive surgery. Considering the importance of faster reepithelialization in preventing complications of photorefractive keratectomy (PRK) and the fact that the features and specifications of these commercially-available lenses are different and their performance as a postoperative bandage lenses would be different also, the aim of this study was comparison the efficacy of senofilcon A and lotrafilcon A after PRK. In this prospective study, 44 patients with PRK in both eyes randomly received a silicon hydrogel contact lens of senofilcon A in one eye and lotrafilcon A in other eye. Then the epithelial defect size, visual acuity and subjective level of pain and discomfort were measured for both eyes and compared on day 1, 3 and 5 postoperatively. There was no statistical difference in rate of reepithelialization between senofilcon A and lotrafilcon A (P > 0.05). The mean pain and discomfort index was significantly lower in eyes with senofilcon A (P contact lenses (BCLs) (P > 0.05). Silicon hydrogel BCLs are safe and effective for corneal reepithelialization and have great therapeutic outcome on visual outcomes after PRK. But, senofilcon A had better effect on postoperative pain and discomfort which made it superior than lotrafilcon A. However for more conclusive results, it is recommended to study larger sample size with evaluation the possible factors responsible for the obtained findings regarding postoperative pain and discomfort.

  11. Roulettes: A weak lensing formalism for strong lensing - II. Derivation and analysis

    CERN Document Server

    Clarkson, Chris

    2016-01-01

    We present a new extension of the weak lensing formalism capable of describing strongly lensed images. This paper accompanies Paper I, where we provided a condensed overview of the approach and illustrated how it works. Here we give all the necessary details, together with some more explicit examples. We solve the non-linear geodesic deviation equation order-by-order, keeping the leading derivatives of the optical tidal matrix, giving rise to a series of maps from which a complete strongly lensed image is formed. The family of maps are decomposed by separating the trace and trace-free parts of each map. Each trace-free tensor represents an independent spin mode, which distort circles into a variety of roulettes in the screen-space. It is shown how summing this series expansion allows us to create large strongly lensed images in regions where convergence, shear and flexion are not sufficient. This paper is a detailed exposition of Paper I which presents the key elements of the subject matter in a wider context...

  12. Detailed cluster lensing profiles at large radii and the impact on cluster weak lensing studies

    Science.gov (United States)

    Oguri, Masamune; Hamana, Takashi

    2011-07-01

    Using a large set of ray tracing in N-body simulations, we examine lensing profiles around massive dark haloes in detail, with a particular emphasis on the profile at around the virial radii. We compare radial convergence profiles, which are measured accurately in the ray-tracing simulations by stacking many dark haloes, with our simple analytic model predictions. Our analytic models consist of a main halo, which is modelled by the Navarro-Frenk-White (NFW) density profile with three different forms of the truncation, plus the correlated matter (two-halo term) around the main halo. We find that the smoothly truncated NFW profile best reproduces the simulated lensing profiles, out to more than 10 times the virial radius. We then use this analytic model to investigate potential biases in cluster weak lensing studies in which a single, untruncated NFW component is usually assumed in interpreting observed signals. We find that cluster masses, inferred by fitting reduced tangential shear profiles with the NFW profile, tend to be underestimated by ˜5-10 per cent if fitting is performed out to ˜10-30 arcmin. In contrast, the concentration parameter is overestimated typically by ˜20 per cent for the same fitting range. We also investigate biases in computing the signal-to-noise ratio of weak lensing mass peaks, finding them to be ≲4 per cent for significant mass peaks. In the appendices, we provide useful formulae for the smoothly truncated NFW profile.

  13. Contact Lenses for Keratoconus- Current Practice

    Science.gov (United States)

    Moschos, Marilita M.; Nitoda, Eirini; Georgoudis, Panagiotis; Balidis, Miltos; Karageorgiadis, Eleftherios; Kozeis, Nikos

    2017-01-01

    Background: Keratoconus is a chronic, bilateral, usuallly asymmetrical, non-inflammatory, ectatic disorder, being characterized by progressive steepening, thinning and apical scarring of the cornea. Initially, the patient is asymptomatic, but the visual acuity gradually decreases, resulting in significant vision loss due to the development of irregular astigmatism, myopia, corneal thinning and scarring. The classic treatment of visual rehabilitation in keratoconus is based on spectacles and contact lenses (CLs). Objective: To summarize the types of CLs used in the treatment of keratoconus. This is literature review of several important published articles focusing on the visual rehabilitation in keratoconus with CLs. Method: Gas permeable (GP) CLs have been found to achieve better best corrected visual acuity than spectacles, eliminating 3rd-order coma root-mean-square (RMS) error, 3rd-order RMS, and higher-order RMS. However, they have implicated in reduction of corneal basal epithelial cell and anterior stromal keratocyte densities. Soft CLs seem to provide greater comfort and lower cost, but the low oxygen permeability (if the lens is not a silicone hydrogel), and the inability to mask moderate to severe irregular astigmatism are the main disadvantages of them. On the other hand, scleral CLs ensure stable platforms, which eliminate high-order aberrations and provide good centration and visual acuity. Their main disadvantages include the difficulties in application and removal of these lenses along with corneal flattening and swelling. Result: The modern hybrid CLs are indicated in cases of poor centration, poor stability or intolerance with GP lenses. Finally, piggyback CL systems effectively ameliorate visual acuity, but they have been related to corneal neovascularization and giant papillary conjunctivitis. Conclusion: CLs seem to rehabilitate visual performance, diminishing the power of the cylinder and the high-order aberrations. The final choice of CLs is

  14. Spurious Shear in Weak Lensing with LSST

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C.; Kahn, S.M.; Jernigan, J.G.; Peterson, J.R.; AlSayyad, Y.; Ahmad, Z.; Bankert, J.; Bard, D.; Connolly, A.; Gibson, R.R.; Gilmore, K.; Grace, E.; Hannel, M.; Hodge, M.A.; Jee, M.J.; Jones, L.; Krughoff, S.; Lorenz, S.; Marshall, P.J.; Marshall, S.; Meert, A.

    2012-09-19

    The complete 10-year survey from the Large Synoptic Survey Telescope (LSST) will image {approx} 20,000 square degrees of sky in six filter bands every few nights, bringing the final survey depth to r {approx} 27.5, with over 4 billion well measured galaxies. To take full advantage of this unprecedented statistical power, the systematic errors associated with weak lensing measurements need to be controlled to a level similar to the statistical errors. This work is the first attempt to quantitatively estimate the absolute level and statistical properties of the systematic errors on weak lensing shear measurements due to the most important physical effects in the LSST system via high fidelity ray-tracing simulations. We identify and isolate the different sources of algorithm-independent, additive systematic errors on shear measurements for LSST and predict their impact on the final cosmic shear measurements using conventional weak lensing analysis techniques. We find that the main source of the errors comes from an inability to adequately characterise the atmospheric point spread function (PSF) due to its high frequency spatial variation on angular scales smaller than {approx} 10{prime} in the single short exposures, which propagates into a spurious shear correlation function at the 10{sup -4}-10{sup -3} level on these scales. With the large multi-epoch dataset that will be acquired by LSST, the stochastic errors average out, bringing the final spurious shear correlation function to a level very close to the statistical errors. Our results imply that the cosmological constraints from LSST will not be severely limited by these algorithm-independent, additive systematic effects.

  15. Combination of measurements of the top-quark pair production cross section from the Tevatron Collider

    CERN Document Server

    Aaltonen, Timo Antero; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Agnew, James P; Alexeev, Guennadi D; Alkhazov, Georgiy D; Alton, Andrew K; Amerio, Silvia; Amidei, Dante E; Anastassov, Anton Iankov; Annovi, Alberto; Antos, Jaroslav; Apollinari, Giorgio; Appel, Jeffrey A; Arisawa, Tetsuo; Artikov, Akram Muzafarovich; Asaadi, Jonathan A; Ashmanskas, William Joseph; Askew, Andrew Warren; Atkins, Scott; Auerbach, Benjamin; Augsten, Kamil; Aurisano, Adam J; Avila, Carlos A; Azfar, Farrukh A; Badaud, Frederique; Badgett, William Farris; Bae, Taegil; Bagby, Linda F; Baldin, Boris; Bandurin, Dmitry V; Banerjee, Sunanda; Barbaro-Galtieri, Angela; Barberis, Emanuela; Baringer, Philip S; Barnes, Virgil E; Barnett, Bruce Arnold; Barria, Patrizia; Bartlett, JFrederick; Bartos, Pavol; Bassler, Ursula Rita; Bauce, Matteo; Bazterra, Victor; Bean, Alice L; Bedeschi, Franco; Begalli, Marcia; Behari, Satyajit; Bellantoni, Leo; Bellettini, Giorgio; Bellinger, James Nugent; Benjamin, Douglas P; Beretvas, Andrew F; Beri, Suman B; Bernardi, Gregorio; Bernhard, Ralf Patrick; Bertram, Iain A; Besancon, Marc; Beuselinck, Raymond; Bhat, Pushpalatha C; Bhatia, Sudeep; Bhatnagar, Vipin; Bhatti, Anwar Ahmad; Bland, Karen Renee; Blazey, Gerald Charles; Blessing, Susan K; Bloom, Kenneth A; Blumenfeld, Barry J; Bocci, Andrea; Bodek, Arie; Boehnlein, Amber S; Boline, Daniel Dooley; Boos, Edward E; Borissov, Guennadi; Bortoletto, Daniela; Boudreau, Joseph Francis; Boveia, Antonio; Brandt, Andrew; Brandt, Oleg; Brigliadori, Luca; Brock, Raymond L; Bromberg, Carl Michael; Bross, Alan D; Brown, Duncan Paul; Brucken, Erik; Bu, Xue-Bing; Budagov, Ioulian A; Budd, Howard Scott; Buehler, Marc; Buescher, Volker; Bunichev, Viacheslav Yevgenyevich; Burdin, Sergey; Burkett, Kevin Alan; Busetto, Giovanni; Bussey, Peter John; Buszello, Claus Peter; Butti, Pierfrancesco; Buzatu, Adrian; Calamba, Aristotle; Camacho-Perez, Enrique; Camarda, Stefano; Campanelli, Mario; Canelli, Florencia; Carls, Benjamin; Carlsmith, Duncan L; Carosi, Roberto; Carrillo Moreno, Salvador; Casal Larana, Bruno; Casarsa, Massimo; Casey, Brendan Cameron Kieran; Castilla-Valdez, Heriberto; Castro, Andrea; Catastini, Pierluigi; Caughron, Seth Aaron; Cauz, Diego; Cavaliere, Viviana; Cavalli-Sforza, Matteo; Cerri, Alessandro; Cerrito, Lucio; Chakrabarti, Subhendu; Chan, Kwok Ming Leo; Chandra, Avdhesh; Chapon, Emilien; Chen, Guo; Chen, Yen-Chu; Chertok, Maxwell Benjamin; Chiarelli, Giorgio; Chlachidze, Gouram; Cho, Kihyeon; Cho, Sung-Woong; Choi, Suyong; Chokheli, Davit; Choudhary, Brajesh C; Cihangir, Selcuk; Claes, Daniel R; Clark, Allan Geoffrey; Clarke, Christopher Joseph; Clutter, Justace Randall; Convery, Mary Elizabeth; Conway, John Stephen; Cooke, Michael P; Cooper, William Edward; Corbo, Matteo; Corcoran, Marjorie D; Cordelli, Marco; Couderc, Fabrice; Cousinou, Marie-Claude; Cox, Charles Alexander; Cox, David Jeremy; Cremonesi, Matteo; Cruz Alonso, Daniel; Cuevas Maestro, Javier; Culbertson, Raymond Lloyd; Cutts, David; Das, Amitabha; D'Ascenzo, Nicola; Datta, Mousumi; Davies, Gavin John; de Barbaro, Pawel; de Jong, Sijbrand Jan; De La Cruz-Burelo, Eduard; Deliot, Frederic; Demina, Regina; Demortier, Luc M; Deninno, Maria Maddalena; Denisov, Dmitri S; Denisov, Sergei P; D'Errico, Maria; Desai, Satish Vijay; Deterre, Cecile; DeVaughan, Kayle Otis; Devoto, Francesco; Di Canto, Angelo; Di Ruzza, Benedetto; Diehl, HThomas; Diesburg, Michael; Ding, Pengfei; Dittmann, Jay Richard; Dominguez, D. Aaron M.; Donati, Simone; D'Onofrio, Monica; Dorigo, Mirco; Driutti, Anna; Dubey, Abhinav Kumar; Dudko, Lev V; Duperrin, Arnaud; Dutt, Suneel; Eads, Michael T; Ebina, Koji; Edgar, Ryan Christopher; Edmunds, Daniel L; Elagin, Andrey L; Ellison, John A; Elvira, VDaniel; Enari, Yuji; Erbacher, Robin D; Errede, Steven Michael; Esham, Benjamin; Evans, Harold G; Evdokimov, Valeri N; Farrington, Sinead Marie; Feng, Lei; Ferbel, Thomas; Fernández Ramos, Juan Pablo; Fiedler, Frank; Field, Richard D; Filthaut, Frank; Fisher, Wade Cameron; Fisk, HEugene; Flanagan, Gene U; Forrest, Robert David; Fortner, Michael R; Fox, Harald; Franklin, Melissa EB; Freeman, John Christian; Frisch, Henry J; Fuess, Stuart C; Funakoshi, Yujiro; Galloni, Camilla; Garbincius, Peter H; Garcia-Bellido, Aran; Garcia-Gonzalez, Jose Andres; Garfinkel, Arthur F; Garosi, Paola; Gavrilov, Vladimir B; Geng, Weigang; Gerber, Cecilia Elena; Gerberich, Heather Kay; Gerchtein, Elena A; Gershtein, Yuri S; Giagu, Stefano; Giakoumopoulou, Viktoria Athina; Gibson, Karen Ruth; Ginsburg, Camille Marie; Ginther, George E; Giokaris, Nikos D; Giromini, Paolo; Giurgiu, Gavril A; Glagolev, Vladimir; Glenzinski, Douglas Andrew; Gold, Michael S; Goldin, Daniel; Golossanov, Alexander; Golovanov, Georgy Anatolievich; Gomez, Gervasio; Gomez-Ceballos, Guillelmo; Goncharov, Maxim T; González López, Oscar; Gorelov, Igor V; Goshaw, Alfred T; Goulianos, Konstantin A; Gramellini, Elena; Grannis, Paul D; Greder, Sebastien; Greenlee, Herbert B; Grenier, Gerald Jean; Grinstein, Sebastian; Gris, Phillipe Luc; Grivaz, Jean-Francois; Grohsjean, Alexander; Grosso-Pilcher, Carla; Group, Robert Craig; Gruenendahl, Stefan; Gruenewald, Martin Werner; Guillemin, Thibault; Guimaraes da Costa, Joao; Gutierrez, Gaston R; Gutierrez, Phillip; Hahn, Stephen R; Haley, Joseph Glenn Biddle; Han, Ji-Yeon; Han, Liang; Happacher, Fabio; Hara, Kazuhiko; Harder, Kristian; Hare, Matthew Frederick; Harel, Amnon; Harr, Robert Francis; Harrington-Taber, Timothy; Hatakeyama, Kenichi; Hauptman, John Michael; Hays, Christopher Paul; Hays, Jonathan M; Head, Tim; Hebbeker, Thomas; Hedin, David R; Hegab, Hatim; Heinrich, Joel G; Heinson, Ann; Heintz, Ulrich; Hensel, Carsten; Heredia-De La Cruz, Ivan; Herndon, Matthew Fairbanks; Herner, Kenneth Richard; Hesketh, Gavin G; Hildreth, Michael D; Hirosky, Robert James; Hoang, Trang; Hobbs, John D; Hocker, James Andrew; Hoeneisen, Bruce; Hogan, Julie; Hohlfeld, Mark; Holzbauer, Jenny Lyn; Hong, Ziqing; Hopkins, Walter Howard; Hou, Suen Ray; Howley, Ian James; Hubacek, Zdenek; Hughes, Richard Edward; Husemann, Ulrich; Hussein, Mohammad; Huston, Joey Walter; Hynek, Vlastislav; Iashvili, Ia; Ilchenko, Yuriy; Illingworth, Robert A; Introzzi, Gianluca; Iori, Maurizio; Ito, Albert S; Ivanov, Andrew Gennadievich; Jabeen, Shabnam; Jaffre, Michel J; James, Eric B; Jang, Dongwook; Jayasinghe, Ayesh; Jayatilaka, Bodhitha Anjalike; Jeon, Eun-Ju; Jeong, Min-Soo; Jesik, Richard L; Jiang, Peng; Jindariani, Sergo Robert; Johns, Kenneth Arthur; Johnson, Emily; Johnson, Marvin E; Jonckheere, Alan M; Jones, Matthew T; Jonsson, Per Martin; Joo, Kyung Kwang; Joshi, Jyoti; Jun, Soon Yung; Jung, Andreas Werner; Junk, Thomas R; Juste, Aurelio; Kajfasz, Eric; Kambeitz, Manuel; Kamon, Teruki; Karchin, Paul Edmund; Karmanov, Dmitriy Y; Kasmi, Azeddine; Kato, Yukihiro; Katsanos, Ioannis; Kehoe, Robert Leo Patrick; Kermiche, Smain; Ketchum, Wesley Robert; Keung, Justin Kien; Khalatyan, Norayr; Khanov, Alexander; Kharchilava, Avto; Kharzheev, Yuri N; Kilminster, Benjamin John; Kim, DongHee; Kim, Hyunsoo; Kim, Jieun; Kim, Min Jeong; Kim, Shin-Hong; Kim, Soo Bong; Kim, Young-Jin; Kim, Young-Kee; Kimura, Naoki; Kirby, Michael H; Kiselevich, Ivan Lvovich; Knoepfel, Kyle James; Kohli, Jatinder M; Kondo, Kunitaka; Kong, Dae Jung; Konigsberg, Jacobo; Kotwal, Ashutosh Vijay; Kozelov, Alexander V; Kraus, James Alexander; Kreps, Michal; Kroll, IJoseph; Kruse, Mark Charles; Kuhr, Thomas; Kumar, Ashish; Kupco, Alexander; Kurata, Masakazu; Kurca, Tibor; Kuzmin, Valentin Alexandrovich; Laasanen, Alvin Toivo; Lammel, Stephan; Lammers, Sabine Wedam; Lancaster, Mark; Lannon, Kevin Patrick; Latino, Giuseppe; Lebrun, Patrice; Lee, Hyeon-Seung; Lee, Hyun Su; Lee, Jaison; Lee, Seh-Wook; Lee, William M; Lei, Xiaowen; Lellouch, Jeremie; Leo, Sabato; Leone, Sandra; Lewis, Jonathan D; Li, Dikai; Li, Hengne; Li, Liang; Li, Qi-Zhong; Lim, Jeong Ku; Limosani, Antonio; Lincoln, Donald W; Linnemann, James Thomas; Lipaev, Vladimir V; Lipeles, Elliot David; Lipton, Ronald J; Lister, Alison; Liu, Hao; Liu, Huanzhao; Liu, Qiuguang; Liu, Tiehui Ted; Liu, Yanwen; Lobodenko, Alexandre; Lockwitz, Sarah E; Loginov, Andrey Borisovich; Lokajicek, Milos; Lopes de Sa, Rafael; Lucchesi, Donatella; Lucà, Alessandra; Lueck, Jan; Lujan, Paul Joseph; Lukens, Patrick Thomas; Luna-Garcia, Rene; Lungu, Gheorghe; Lyon, Adam Leonard; Lys, Jeremy E; Lysak, Roman; Maciel, Arthur KA; Madar, Romain; Madrak, Robyn Leigh; Maestro, Paolo; Magana-Villalba, Ricardo; Malik, Sarah Alam; Malik, Sudhir; Malyshev, Vladimir L; Manca, Giulia; Manousakis-Katsikakis, Arkadios; Mansour, Jason; Marchese, Luigi; Margaroli, Fabrizio; Marino, Christopher Phillip; Martinez-Ortega, Jorge; Martínez-Perez, Mario; Matera, Keith; Mattson, Mark Edward; Mazzacane, Anna; Mazzanti, Paolo; McCarthy, Robert L; Mcgivern, Carrie Lynne; McNulty, Ronan; Mehta, Andrew; Mehtala, Petteri; Meijer, Melvin M; Melnitchouk, Alexander S; Menezes, Diego D; Mercadante, Pedro Galli; Merkin, Mikhail M; Mesropian, Christina; Meyer, Arnd; Meyer, Jorg Manfred; Miao, Ting; Miconi, Florian; Mietlicki, David John; Mitra, Ankush; Miyake, Hideki; Moed, Shulamit; Moggi, Niccolo; Mondal, Naba K; Moon, Chang-Seong; Moore, Ronald Scott; Morello, Michael Joseph; Mukherjee, Aseet; Mulhearn, Michael James; Muller, Thomas; Murat, Pavel A; Mussini, Manuel; Nachtman, Jane Marie; Nagai, Yoshikazu; Naganoma, Junji; Nagy, Elemer; Nakano, Itsuo; Napier, Austin; Narain, Meenakshi; Nayyar, Ruchika; Neal, Homer A; Negret, Juan Pablo; Nett, Jason Michael; Neu, Christopher Carl; Neustroev, Petr V; Nguyen, Huong Thi; Nigmanov, Turgun S; Nodulman, Lawrence J; Noh, Seoyoung; Norniella Francisco, Olga; Nunnemann, Thomas P; Oakes, Louise Beth; Oh, Seog Hwan; Oh, Young-do; Oksuzian, Iuri Artur; Okusawa, Toru; Orava, Risto Olavi; Hernandez Orduna, Jose de Jesus; Ortolan, Lorenzo; Osman, Nicolas Ahmed; Osta, Jyotsna; Pagliarone, Carmine Elvezio; Pal, Arnab; Palencia, Jose Enrique; Palni, Prabhakar; Papadimitriou, Vaia; Parashar, Neeti; Parihar, Vivek; Park, Sung Keun; Parker, William Chesluk; Partridge, Richard A; Parua, Nirmalya; Patwa, Abid; Pauletta, Giovanni; Paulini, Manfred; Paus, Christoph Maria Ernst; Penning, Bjoern; Perfilov, Maxim Anatolyevich; Peters, Reinhild Yvonne Fatima; Petridis, Konstantinos; Petrillo, Gianluca; Petroff, Pierre; Phillips, Thomas J; Piacentino, Giovanni M; Pianori, Elisabetta; Pilot, Justin Robert; Pitts, Kevin T; Plager, Charles; Pleier, Marc-Andre; Podstavkov, Vladimir M; Pondrom, Lee G; Popov, Alexey V; Poprocki, Stephen; Potamianos, Karolos Jozef; Pranko, Aliaksandr Pavlovich; Prewitt, Michelle; Price, Darren; Prokopenko, Nikolay N; Prokoshin, Fedor; Ptohos, Fotios K; Punzi, Giovanni; Qian, Jianming; Quadt, Arnulf; Quinn, Breese; Ranjan, Niharika; Ratoff, Peter N; Razumov, Ivan A; Redondo Fernández, Ignacio; Renton, Peter B; Rescigno, Marco; Rimondi, Franco; Ripp-Baudot, Isabelle; Ristori, Luciano; Rizatdinova, Flera; Robson, Aidan; Rodriguez, Tatiana Isabel; Rolli, Simona; Rominsky, Mandy Kathleen; Ronzani, Manfredi; Roser, Robert Martin; Rosner, Jonathan L; Ross, Anthony; Royon, Christophe; Rubinov, Paul Michael; Ruchti, Randal C; Ruffini, Fabrizio; Ruiz Jimeno, Alberto; Russ, James S; Rusu, Vadim Liviu; Sajot, Gerard; Sakumoto, Willis Kazuo; Sakurai, Yuki; Sanchez-Hernandez, Alberto; Sanders, Michiel P; Santi, Lorenzo; Santos, Angelo Souza; Sato, Koji; Savage, David G; Saveliev, Valeri; Savoy-Navarro, Aurore; Sawyer, HLee; Scanlon, Timothy P; Schamberger, RDean; Scheglov, Yury A; Schellman, Heidi M; Schlabach, Philip; Schmidt, Eugene E; Schwanenberger, Christian; Schwarz, Thomas A; Schwienhorst, Reinhard H; Scodellaro, Luca; Scuri, Fabrizio; Seidel, Sally C; Seiya, Yoshihiro; Sekaric, Jadranka; Semenov, Alexei; Severini, Horst; Sforza, Federico; Shabalina, Elizaveta K; Shalhout, Shalhout Zaki; Shary, Viacheslav V; Shaw, Savanna; Shchukin, Andrey A; Shears, Tara G; Shepard, Paul F; Shimojima, Makoto; Shochet, Melvyn J; Shreyber-Tecker, Irina; Simak, Vladislav J; Simonenko, Alexander V; Skubic, Patrick Louis; Slattery, Paul F; Sliwa, Krzysztof Jan; Smirnov, Dmitri V; Smith, John Rodgers; Snider, Frederick Douglas; Snow, Gregory R; Snow, Joel Mark; Snyder, Scott Stuart; Soldner-Rembold, Stefan; Song, Hao; Sonnenschein, Lars; Sorin, Maria Veronica; Soustruznik, Karel; St Denis, Richard Dante; Stancari, Michelle Dawn; Stark, Jan; Stentz, Dale James; Stoyanova, Dina A; Strauss, Michael G; Strologas, John; Sudo, Yuji; Sukhanov, Alexander I; Suslov, Igor M; Suter, Louise; Svoisky, Peter V; Takemasa, Ken-ichi; Takeuchi, Yuji; Tang, Jian; Tecchio, Monica; Teng, Ping-Kun; Thom, Julia; Thomson, Evelyn Jean; Thukral, Vaikunth; Titov, Maxim; Toback, David A; Tokar, Stanislav; Tokmenin, Valeriy V; Tollefson, Kirsten Anne; Tomura, Tomonobu; Tonelli, Diego; Torre, Stefano; Torretta, Donatella; Totaro, Pierluigi; Trovato, Marco; Tsai, Yun-Tse; Tsybychev, Dmitri; Tuchming, Boris; Tully, Christopher George T; Ukegawa, Fumihiko; Uozumi, Satoru; Uvarov, Lev; Uvarov, Sergey L; Uzunyan, Sergey A; Van Kooten, Richard J; van Leeuwen, Willem M; Varelas, Nikos; Varnes, Erich W; Vasilyev, Igor A; Vázquez-Valencia, Elsa Fabiola; Velev, Gueorgui; Vellidis, Konstantinos; Verkheev, Alexander Yurievich; Vernieri, Caterina; Vertogradov, Leonid S; Verzocchi, Marco; Vesterinen, Mika; Vidal Marono, Miguel; Vilanova, Didier; Vilar Cortabitarte, Rocio; Vizán Garcia, Jesus Manuel; Vogel, Marcelo; Vokac, Petr; Volpi, Guido; Wagner, Peter; Wahl, Horst D; Wallny, Rainer S; Wang, Michael HLS; Wang, Song-Ming; Warchol, Jadwiga; Waters, David S; Watts, Gordon Thomas; Wayne, Mitchell R; Weichert, Jonas; Welty-Rieger, Leah Christine; Wester, William Carl; Whiteson, Daniel O; Wicklund, Arthur Barry; Wilbur, Scott; Williams, Hugh H; Williams, Mark Richard James; Wilson, Graham Wallace; Wilson, Jonathan Samuel; Wilson, Peter James; Winer, Brian L; Wittich, Peter; Wobisch, Markus; Wolbers, Stephen A; Wolfe, Homer; Wood, Darien Robert; Wright, Thomas Roland; Wu, Xin; Wu, Zhenbin; Wyatt, Terence R; Xie, Yunhe; Yamada, Ryuji; Yamamoto, Kazuhiro; Yamato, Daisuke; Yang, Siqi; Yang, Tingjun; Yang, Un-Ki; Yang, Yu Chul; Yao, Wei-Ming; Yasuda, Takahiro; Yatsunenko, Yuriy A; Ye, Wanyu; Ye, Zhenyu; Yeh, Gong Ping; Yi, Kai; Yin, Hang; Yip, Kin; Yoh, John; Yorita, Kohei; Yoshida, Takuo; Youn, Sungwoo; Yu, Geum Bong; Yu, Intae; Yu, Jiaming; Zanetti, Anna Maria; Zeng, Yu; Zennamo, Joseph; Zhao, Tianqi Gilbert; Zhou, Bing; Zhou, Chen; Zhu, Junjie; Zielinski, Marek; Zieminska, Daria; Zivkovic, Lidija; Zucchelli, Stefano

    2014-04-01

    We combine six measurements of the inclusive top-quark pair (ttbar) production cross section (sigma_ttbar) from data collected with the CDF and D0 detectors at the Fermilab Tevatron with proton anti-proton collisions at sqrt{s} = 1.96 TeV. The data correspond to integrated luminosities of up to 8.8 fb^{-1}. We obtain a value of sigma_ttbar = 7.60 \\pm 0.41 pb for a top-quark mass of m_t=172.5 GeV. The contributions to the uncertainty are 0.20 pb from statistical sources, 0.29 pb from systematic sources, and 0.21 pb from the uncertainty on the integrated luminosity. The result is in good agreement with the standard model expectation of 7.35^{+0.28}_{-0.33} pb at NNLO+NNLL in pertubative QCD.

  16. Single top quarks at the Tevatron and observation of the s-channel production mode

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The presentation gives an overview of single-top-quark production at the Tevatron proton-antiproton collider. The talk covers measurements of the total s+t channel production cross section and the extraction of the CKM matrix element |V_tb|. Furthermore, separate analyses of the s-channel and t-channel production modes are discussed. The data correspond to total integrated luminosities of up to 9.7 fb-1 per experiment and represent in most cases the full Run-II dataset. Through a combination of the CDF and D0 measurements the first observation of single-top-quark production in the s-channel is claimed. This is particularly highlighted in the seminar.

  17. NNLO QCD predictions for fully-differential top-quark pair production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Czakon, Michał; Fiedler, Paul [Institut für Theoretische Teilchenphysik und Kosmologie,RWTH Aachen University, D-52056 Aachen (Germany); Heymes, David; Mitov, Alexander [Cavendish Laboratory, University of Cambridge,Cambridge CB3 0HE (United Kingdom)

    2016-05-05

    We present a comprehensive study of differential distributions for Tevatron top-pair events at the level of stable top quarks. All calculations are performed in NNLO QCD with the help of a fully differential partonic Monte-Carlo and are exact at this order in perturbation theory. We present predictions for all kinematic distributions for which data exists. Particular attention is paid on the top-quark forward-backward asymmetry which we study in detail. We compare the NNLO results with existing approximate NNLO predictions as well as differential distributions computed with different parton distribution sets. Theory errors are significantly smaller than current experimental ones with overall agreement between theory and data.

  18. Status of the observed and predicted b anti-b production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Happacher, F.; Giromini, P.; /Frascati; Ptohos, F.; /Cyprus U.

    2005-09-01

    The authors review the experimental status of the b-quark production at the Fermilab Tevatron. They compare all available measurements to perturbative QCD predictions (NLO and FONLL) and also to the parton-level cross section evaluated with parton-shower Monte Carlo generators. They examine both the single b cross section and the so called b{bar b} correlations. The review shows that the experimental situation is quite complicated because the measurements appear to be inconsistent among themselves. In this situation, there is no solid basis to either claim that perturbative QCD is challenged by these measurements or, in contrast, that long-standing discrepancies between data and theory have been resolved by incrementally improving the measurements and the theoretical prediction.

  19. Search for Neutral Higgs Bosons in Events with Multiple Bottom Quarks at the Tevatron

    CERN Document Server

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Fernandez, J.P.; Fiedler, F.; Field, R.; Filthaut, F.; Fisher, W.; Fisk, H.E.; Flanagan, G.; Forrest, R.; Fortner, M.; Fox, H.; Frank, M.J.; Franklin, M.; Freeman, J.C.; Fuess, S.; Funakoshi, Y.; Furic, I.; Gallinaro, M.; Garcia-Bellido, A.; Garcia, J.E.; Garcia-Gonzalez, J.A.; Garcia-Guerra, G.A.; Garfinkel, A.F.; Garosi, P.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C.E.; Gerberich, H.; Gerchtein, E.; Gershtein, Y.; Giagu, S.; Giakoumopoulou, V.; Giannetti, P.; Gibson, K.; Ginsburg, C.M.; Ginther, G.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Goldschmidt, N.; Golossanov, A.; Golovanov, G.; Gomez-Ceballos, G.; Gomez, G.; Goncharov, M.; Gonzalez, O.; Gorelov, I.; Goshaw, A.T.; Goulianos, K.; Goussiou, A.; Grannis, P.D.; Greder, S.; Greenlee, H.; Grenier, G.; Grinstein, S.; Gris, Ph.; Grivaz, J.F.; Grohsjean, A.; Grosso-Pilcher, C.; Group, R.C.; Grunendahl, S.; Grunewald, M.W.; Guillemin, T.; Guimaraes da Costa, J.; Gutierrez, G.; Gutierrez, P.; Hagopian, S.; Hahn, S.R.; Haley, J.; Halkiadakis, E.; Hamaguchi, A.; Han, J.Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, D.; Hare, M.; Harel, A.; Harr, R.F.; Hatakeyama, K.; Hauptman, J.M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Heck, M.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A.P.; Heintz, U.; Hensel, C.; Heredia-de La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hewamanage, S.; Hildreth, M.D.; Hirosky, R.; Hoang, T.; Hobbs, J.D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Hopkins, W.; Horn, D.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R.E.; Hurwitz, M.; Husemann, U.; Hussain, N.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A.S.; Ivanov, A.; Jabeen, S.; Jaffre, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E.J.; Jeong, M.S.; Jesik, R.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K.K.; Joshi, J.; Jun, S.Y.; Jung, A.W.; Junk, T.R.; Juste, A.; Kaadze, K.; Kajfasz, E.; Kamon, T.; Karchin, P.E.; Karmanov, D.; Kasmi, A.; Kasper, P.A.; Kato, Y.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y.N.; Khotilovich, V.; Kilminster, B.; Kim, D.H.; Kim, H.S.; Kim, J.E.; Kim, M.J.; Kim, S.B.; Kim, S.H.; Kim, Y.J.; Kim, Y.K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Klimenko, S.; Knoepfel, K.; Kohli, J.M.; Kondo, K.; Kong, D.J.; Konigsberg, J.; Kotwal, A.V.; Kozelov, A.V.; Kraus, J.; Kreps, M.; Kroll, J.; Krop, D.; Kruse, M.; Krutelyov, V.; Kuhr, T.; Kulikov, S.; Kumar, A.; Kupco, A.; Kurata, M.; Kurca, T.; Kuzmin, V.A.; Kwang, S.; Laasanen, A.T.; Lami, S.; Lammel, S.; Lammers, S.; Lancaster, M.; Lander, R.L.; Landsberg, G.; Lannon, K.; Lath, A.; Latino, G.; Lebrun, P.; LeCompte, T.; Lee, E.; Lee, H.S.; Lee, H.S.; Lee, J.S.; Lee, S.W.; Lee, S.W.; Lee, W.M.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J.D.; Li, H.; Li, L.; Li, Q.Z.; Lim, J.K.; Limosani, A.; Lincoln, D.; Lin, C.J.; Lindgren, M.; Linnemann, J.; Lipaev, V.V.; Lipeles, E.; Lipton, R.; Lister, A.; Litvintsev, D.O.; Liu, C.; Liu, H.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lubatti, H.J.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A.L.; Lysak, R.; Lys, J.; Maciel, A.K.A.; Madar, R.; Madrak, R.; Maeshima, K.; Maestro, P.; Magana-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V.L.; Manca, G.; Manousakis-Katsikakis, A.; Maravin, Y.; Margaroli, F.; Marino, C.; Martinez, M.; Martinez-Ortega, J.; Mastrandrea, P.; Matera, K.; Mattson, M.E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McFarland, K.S.; McGivern, C.L.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M.M.; Melnitchouk, A.; Menezes, D.; Mercadante, P.G.; Merkin, M.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N.K.; Mondragon, M.N.; Moon, C.S.; Moore, R.; Morello, M.J.; Morlock, J.; Movilla Fernandez, P.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Naimuddin, M.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H.A.; Negret, J.P.; Nett, J.; Neubauer, M.S.; Neu, C.; Neustroev, P.; Nielsen, J.; Nodulman, L.; Noh, S.Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S.H.; Oh, Y.D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Osta, J.; Padilla, M.; Pagan Griso, S.; Pagliarone, C.; Pal, A.; Palencia, E.; Papadimitriou, V.; Paramonov, A.A.; Parashar, N.; Parihar, V.; Park, S.K.; Partridge, R.; Parua, N.; Patrick, J.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Pellett, D.E.; Penning, B.; Penzo, A.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Petroff, P.; Phillips, T.J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.A.; Podesta-Lerma, P.L.M.; Podstavkov, V.M.; Pondrom, L.; Popov, A.V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Rahaman, A.; Ramakrishnan, V.; Rangel, M.S.; Ranjan, K.; Ranjan, N.; Ratoff, P.N.; Razumov, I.; Redondo, I.; Renkel, P.; Renton, P.; Rescigno, M.; Riddick, T.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodrigo, T.; Rodriguez, T.; Rogers, E.; Rolli, S.; Rominsky, M.; Roser, R.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Safonov, A.; Sajot, G.; Sakumoto, W.K.; Sakurai, Y.; Salcido, P.; Sanchez-Hernandez, A.; Sanders, M.P.; Santi, L.; Santos, A.S.; Sato, K.; Savage, G.; Saveliev, V.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R.D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schlobohm, S.; Schmidt, A.; Schmidt, E.E.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scribano, A.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S.Z.; Shary, V.; Shaw, S.; Shchukin, A.A.; Shears, T.; Shepard, P.F.; Shimojima, M.; Shivpuri, R.K.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Sinervo, P.; Skubic, P.; Slattery, P.; Sliwa, K.; Smirnov, D.; Smith, J.R.; Smith, K.J.; Snider, F.D.; Snow, G.R.; Snow, J.; Snyder, S.; Soha, A.; Soldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; Squillacioti, P.; St. Denis, R.; Stancari, M.; Stark, J.; Stelzer-Chilton, O.; Stelzer, B.; Stentz, D.; Stoyanova, D.A.; Strauss, M.; Strologas, J.; Strycker, G.L.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takahashi, M.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P.K.; Thom, J.; Thome, J.; Thompson, G.A.; Thomson, E.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V.V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.T.; Tschann-Grimm, K.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; W.van Leeuwen, M.; Varelas, N.; Varganov, A.; Varnes, E.W.; Vasilyev, I.A.; Vazquez, F.; Velev, G.; Vellidis, C.; Verdier, P.; Verkheev, A.Y.; Vertogradov, L.S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vila, I.; Vilanova, D.; Vilar, R.; Vizan, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wagner, R.L.; Wahl, H.D.; Wakisaka, T.; Wallny, R.; Wang, S.M.; Wang, M.H.L.S.; Warburton, A.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W.C., III; White, A.; Whiteson, D.; Wick, F.; Wicke, D.; Wicklund, A.B.; Wicklund, E.; Wilbur, S.; Williams, H.H.; Williams, M.R.J.; Wilson, G.W.; Wilson, J.S.; Wilson, P.; Winer, B.L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfe, H.; Wood, D.R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T.R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U.K.; Yang, W.C.; Yang, Y.C.; Yao, W.M.; Yasuda, T.; Yatsunenko, Y.A.; Ye, W.; Ye, Z.; Yeh, G.P.; Yi, K.; Yin, H.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S.W.; Yu, G.B.; Yu, I.; Yu, J.M.; Yu, S.S.; Yun, J.C.; Zanetti, A.; Zeng, Y.; Zennamo, J.; Zhao, T.; Zhao, T.G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.

    2012-01-01

    The combination of searches performed by the CDF and D0 collaborations at the Fermilab Tevatron Collider for neutral Higgs bosons produced in association with b quarks is reported. The data, corresponding to 2.6 fb-1 of integrated luminosity at CDF and 5.2 fb-1 at D0, have been collected in final states containing three or more b jets. Upper limits are set on the cross section multiplied by the branching ratio varying between 44 pb and 0.7 pb in the Higgs boson mass range 90 to 300 GeV, assuming production of a narrow scalar boson. Significant enhancements to the production of Higgs bosons can be found in theories beyond the standard model, for example in supersymmetry. The results are interpreted as upper limits in the parameter space of the minimal supersymmetric standard model in a benchmark scenario favoring this decay mode.

  20. Search for the Higgs-Boson with the CDF experiment at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Hennecke, Martin [Univ. of Karlsruhe (Germany)

    2005-06-10

    A search for a low-mass SM Higgs-Boson in the channel WH → lvb$\\bar{b}$ has been performed using neural networks. The data were taken by the CDF experiment at the p-$\\bar{p}$ collider Tevatron from 2000-2003, corresponding to in integrated luminosity of Lint = 162 pb-1 at a CMS-energy of √s = 1.96 TeV. 95% confidence level upper limits are set on σ × BR, the product of the production cross section times the Branching ratio, as a function of the Higgs boson mass. Cross sections above 8 pb are excluded for six different Higgs masses between 110 GeV/c2 and 150 GeV/c2. The required integrated luminosities for a 95% C.L. exclusion, 3σ evidence and 5σ discovery are calculated.

  1. Polarization for prompt J/ψ and ψ(2s) production at the Tevatron and LHC.

    Science.gov (United States)

    Gong, Bin; Wan, Lu-Ping; Wang, Jian-Xiong; Zhang, Hong-Fei

    2013-01-25

    With nonrelativistic QCD factorization, we present the first complete next-to-leading order study on the polarization of prompt J/ψ hadroproduction by including feeddown from χ(c)((3)P(J)(1),(3)S(1)(8)) and ψ(2s) which turn out to be very important parts. By using the color-octet long-distance matrix elements obtained from a combined fit of the measurements at the Tevatron and LHC for J/ψ, ψ(2s) and χ(c), the prompt J/ψ polarization predictions are presented, and the results are in agreement with the CDF run I data (except two points), but in conflict with the CDF run II data, while they are close to the ALICE data (inclusive J/ψ). The measurements at the LHC are expected to clarify the situation.

  2. Model-independent analysis of the Fermilab Tevatron turn-by-turn beam position monitor measurements

    Energy Technology Data Exchange (ETDEWEB)

    Petrenko, A.V.; /Novosibirsk, IYF; Valishev, A.A.; Lebedev, V.A.; /Fermilab

    2011-09-01

    Coherent transverse beam oscillations in the Tevatron were analyzed with the model-independent analysis (MIA) technique. This allowed one to obtain the model-independent values of coupled betatron amplitudes, phase advances, and dispersion function around the ring from a single dipole kick measurement. In order to solve the MIA mode mixing problem which limits the accuracy of determination of the optical functions, we have developed a new technique of rotational MIA mode untangling. The basic idea is to treat each beam position monitor (BPM) as two BPMs separated in a ring by exactly one turn. This leads to a simple criterion of MIA mode separation: the betatron phase advance between any BPM and its counterpart shifted by one turn should be equal to the betatron tune and therefore should not depend on the BPM position in the ring. Furthermore, we describe a MIA-based technique to locate vibrating magnets in a storage ring.

  3. Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

    Science.gov (United States)

    Aaltonen, T.; Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Askew, A.; Atkins, S.; Auerbach, B.; Augsten, K.; Aurisano, A.; Aushev, V.; Aushev, Y.; Avila, C.; Azfar, F.; Badaud, F.; Badgett, W.; Bae, T.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barbaro-Galtieri, A.; Barberis, E.; Baringer, P.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartlett, J. F.; Bartos, P.; Bassler, U.; Bauce, M.; Bazterra, V.; Bean, A.; Bedeschi, F.; Begalli, M.; Behari, S.; Bellantoni, L.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Bhatti, A.; Bland, K. R.; Blazey, G.; Blessing, S.; Bloom, K.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bortoletto, D.; Borysova, M.; Boudreau, J.; Boveia, A.; Brandt, A.; Brandt, O.; Brigliadori, L.; Brochmann, M.; Brock, R.; Bromberg, C.; Bross, A.; Brown, D.; Brucken, E.; Bu, X. B.; Budagov, J.; Budd, H. S.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buszello, C. P.; Butti, P.; Buzatu, A.; Calamba, A.; Camacho-Pérez, E.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Casey, B. C. K.; Castilla-Valdez, H.; Castro, A.; Catastini, P.; Caughron, S.; Cauz, D.; Cavaliere, V.; Cerri, A.; Cerrito, L.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapelain, A.; Chapon, E.; Chen, G.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Cho, S. W.; Choi, S.; Chokheli, D.; Choudhary, B.; Cihangir, S.; Claes, D.; Clark, A.; Clarke, C.; Clutter, J.; Convery, M. E.; Conway, J.; Cooke, M.; Cooper, W. E.; Corbo, M.; Corcoran, M.; Cordelli, M.; Couderc, F.; Cousinou, M.-C.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; Cuth, J.; Cutts, D.; Das, A.; d'Ascenzo, N.; Datta, M.; Davies, G.; de Barbaro, P.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Demortier, L.; Deninno, M.; Denisov, D.; Denisov, S. P.; D'Errico, M.; Desai, S.; Deterre, C.; DeVaughan, K.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dittmann, J. R.; Dominguez, A.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Drutskoy, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Ebina, K.; Edgar, R.; Edmunds, D.; Elagin, A.; Ellison, J.; Elvira, V. D.; Enari, Y.; Erbacher, R.; Errede, S.; Esham, B.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Farrington, S.; Fauré, A.; Feng, L.; Ferbel, T.; Fernández Ramos, J. P.; Fiedler, F.; Field, R.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Flanagan, G.; Forrest, R.; Fortner, M.; Fox, H.; Franc, J.; Franklin, M.; Freeman, J. C.; Frisch, H.; Fuess, S.; Funakoshi, Y.; Galloni, C.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Garfinkel, A. F.; Garosi, P.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gerberich, H.; Gerchtein, E.; Gershtein, Y.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Ginther, G.; Giokaris, N.; Giromini, P.; Glagolev, V.; Glenzinski, D.; Gogota, O.; Gold, M.; Goldin, D.; Golossanov, A.; Golovanov, G.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grosso-Pilcher, C.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Guimaraes da Costa, J.; Gutierrez, G.; Gutierrez, P.; Hahn, S. R.; Haley, J.; Han, J. Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, M.; Harel, A.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hauptman, J. M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Hong, Z.; Hopkins, W.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A. S.; Ivanov, A.; Jabeen, S.; Jaffré, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E. J.; Jeong, M. S.; Jesik, R.; Jiang, P.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K. K.; Joshi, J.; Jun, S. Y.; Jung, A. W.; Junk, T. R.; Juste, A.; Kajfasz, E.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Karmanov, D.; Kasmi, A.; Kato, Y.; Katsanos, I.; Kaur, M.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. H.; Kim, S. B.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Kohli, J. M.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kozelov, A. V.; Kraus, J.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kumar, A.; Kupco, A.; Kurata, M.; Kurča, T.; Kuzmin, V. A.; Laasanen, A. T.; Lammel, S.; Lammers, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lebrun, P.; Lee, H. S.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J. D.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Limosani, A.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipeles, E.; Lipton, R.; Lister, A.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lucchesi, D.; Lucà, A.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A. L.; Lys, J.; Lysak, R.; Maciel, A. K. A.; Madar, R.; Madrak, R.; Maestro, P.; Magaña-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V. L.; Manca, G.; Manousakis-Katsikakis, A.; Mansour, J.; Marchese, L.; Margaroli, F.; Marino, P.; Martínez-Ortega, J.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McGivern, C. L.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Mesropian, C.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N. K.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Nett, J.; Neustroev, P.; Nguyen, H. T.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Pagliarone, C.; Pal, A.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parashar, N.; Parihar, V.; Park, S. K.; Parker, W.; Partridge, R.; Parua, N.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.-A.; Podstavkov, V. M.; Pondrom, L.; Popov, A. V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Ratoff, P. N.; Razumov, I.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodriguez, T.; Rolli, S.; Rominsky, M.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sajot, G.; Sakumoto, W. K.; Sakurai, Y.; Sánchez-Hernández, A.; Sanders, M. P.; Santi, L.; Santos, A. S.; Sato, K.; Savage, G.; Saveliev, V.; Savitskyi, M.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schmidt, E. E.; Schott, M.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S. Z.; Shary, V.; Shaw, S.; Shchukin, A. A.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shkola, O.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Skubic, P.; Slattery, P.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; St. Denis, R.; Stancari, M.; Stark, J.; Stefaniuk, N.; Stentz, D.; Stoyanova, D. A.; Strauss, M.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V. V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.-T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Vázquez, F.; Velev, G.; Vellidis, C.; Verkheev, A. Y.; Vernieri, C.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vilanova, D.; Vilar, R.; Vizán, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wahl, H. D.; Wallny, R.; Wang, M. H. L. S.; Wang, S. M.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W. C.; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Williams, M. R. J.; Wilson, G. W.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfmeister, H.; Wood, D. R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yeh, G. P.; Yi, K.; Yin, H.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S. W.; Yu, G. B.; Yu, I.; Yu, J. M.; Zanetti, A. M.; Zeng, Y.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.; CDF Collaboration

    2018-01-01

    The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of √{s }=1.96 TeV . We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is AFBt t ¯=0.128 ±0.025 . The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

  4. Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, Timo Antero; et al.

    2017-09-14

    The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of $\\sqrt s =1.96$ TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is $A_{\\mathrm{FB}}^{t\\bar{t}} = 0.128 \\pm 0.025$. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

  5. Top anti-top Asymmetries at the Tevatron and the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Yvonne Reinhild [DESY

    2012-11-01

    The heaviest known elementary particle today, the top quark, has been discovered in 1995 by the CDF and D0 collaborations at the Tevatron proton antiproton collider at Fermilab. Recently, the CDF and D0 collaborations have studied the forward-backward asymmetry in ttbar events, resulting in measured values larger than the standard model prediction. With the start of the LHC at CERN in 2010, a new top quark factory has opened and asymmetry measurements in ttbar have also been performed in a proton proton environment with higher collision energy. No deviations from the standard model have been noticed so far in the measurements of ATLAS and CMS. This article discusses recent results of asymmetry measurements in ttbar events of the ATLAS, CDF, CMS and D0 collaborations.

  6. Magnified Weak Lensing Cross Correlation Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ulmer, Melville P., Clowe, Douglas I.

    2010-11-30

    This project carried out a weak lensing tomography (WLT) measurement around rich clusters of galaxies. This project used ground based photometric redshift data combined with HST archived cluster images that provide the WLT and cluster mass modeling. The technique has already produced interesting results (Guennou et al, 2010,Astronomy & Astrophysics Vol 523, page 21, and Clowe et al, 2011 to be submitted). Guennou et al have validated that the necessary accuracy can be achieved with photometric redshifts for our purposes. Clowe et al titled "The DAFT/FADA survey. II. Tomographic weak lensing signal from 10 high redshift clusters," have shown that for the **first time** via this purely geometrical technique, which does not assume a standard rod or candle, that a cosmological constant is **required** for flat cosmologies. The intent of this project is not to produce the best constraint on the value of the dark energy equation of state, w. Rather, this project is to carry out a sustained effort of weak lensing tomography that will naturally feed into the near term Dark Energy Survey (DES) and to provide invaluable mass calibration for that project. These results will greatly advance a key cosmological method which will be applied to the top-rated ground-based project in the Astro2020 decadal survey, LSST. Weak lensing tomography is one of the key science drivers behind LSST. CO-I Clowe is on the weak lensing LSST committee, and senior scientist on this project, at FNAL James Annis, plays a leading role in the DES. This project has built on successful proposals to obtain ground-based imaging for the cluster sample. By 1 Jan, it is anticipated the project will have accumulated complete 5-color photometry on 30 (or about 1/3) of the targeted cluster sample (public webpage for the survey is available at http://cencos.oamp.fr/DAFT/ and has a current summary of the observational status of various clusters). In all, the project has now been awarded the equivalent of over 60

  7. Contact lenses in pediatrics study in Singapore.

    Science.gov (United States)

    Li, Lim; Moody, Kurt; Tan, Donald T H; Yew, Khoo Chong; Ming, Por Yong; Long, Quah Boon

    2009-07-01

    Previous studies in the United States have evaluated the benefits of soft contact lenses (CLs) in 8- to 12-year-old children and 13- to 17-year-old teens. This study was undertaken in Singapore and evaluated the safety, efficacy, and physiologic performance of daily disposable soft lenses in a population of children. In this open-label, bilateral, 3-month dispensing study, 59 children (8-11 years) were fit with etafilcon A spherical or toric daily disposable lenses (1-DAY ACUVUE or 1-DAY ACUVUE for ASTIGMATISM, Vistakon, Jacksonville, FL). All subjects were neophytes requiring visual correction in both eyes. The refractive inclusion criteria were plano to -9.00 diopter (D) with astigmatism of < or =2.00DC in both eyes, or hyperopia of +0.50 to +6.00D with astigmatism of 0.75D or less. The subjects underwent follow-up evaluations, which included a questionnaire for parents and subjects, at 1 week, 1 month, and 3 months. Of the 59 subjects enrolled, 53 (90%) completed the study successfully. Six subjects were discontinued because of lens handling difficulties (four), unacceptable lens fit (one), and an adverse event (one). Adverse events were reported in three subjects, including the discontinuation, and in each case were due to a chalazion. Overall vision quality, overall comfort, and end-of-day comfort were graded significantly better at each of the follow-up visits compared with baseline with spectacles (P< or =0.0001). Both handling and reported symptoms improved during the course of the study. The questionnaire results indicated that most of both parents and subjects preferred CLs to spectacles across a wide variety of aspects including vision, comfort, handling, and appearance. Significantly, more limbal and bulbar hyperemia was noted at follow-up visits than at baseline (P=0.0001); however, no instances of hyperemia greater than grade 2 were noted at any visit. Significantly, more corneal staining was also noted at the 1- and 3-month follow-up visits than at

  8. Optimizing outcomes with multifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Gitansha Shreyas Sachdev

    2017-01-01

    Full Text Available Modern day cataract surgery is evolving from a visual restorative to a refractive procedure. The advent of multifocal intraocular lenses (MFIOLs allows greater spectacle independence and increased quality of life postoperatively. Since the inception in 1980s, MFIOLs have undergone various technical advancements including trifocal and extended depth of vision implants more recently. A thorough preoperative workup including the patients' visual needs and inherent ocular anatomy allows us to achieve superior outcomes. This review offers a comprehensive overview of the various types of MFIOLs and principles of optimizing outcomes through a comprehensive preoperative screening and management of postoperative complications.

  9. Vibrational microspectroscopy analysis of human lenses

    Science.gov (United States)

    Paluszkiewicz, C.; Piergies, N.; Sozańska, A.; Chaniecki, P.; Rękas, M.; Miszczyk, J.; Gajda, M.; Kwiatek, W. M.

    2018-01-01

    In this study we present vibrational analysis of healthy (non-affected by cataract) and cataractous human lenses by means of Raman and FTIR spectroscopy methods. The performed analysis provides complex information about the secondary structure of the proteins and conformational changes of the amino acid residues due to the formation of opacification of human lens. Briefly, the changes in the conformation of the Tyr and Trp residues and the protein secondary structure between the healthy and cataractous samples, were recognized. Moreover, the observed spectral pattern suggests that the process of cataract development does not occur uniformly over the entire volume of the lens.

  10. Ambient beam motion and its excitation by ghost lines in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; /Fermilab

    2011-03-01

    Transverse betatron motion of the Tevatron proton beam is measured and analyzed. It is shown that the motion is coherent and excited by external sources of unknown origins. Observations of the time-varying 'ghost lines' in the betatron spectrum are reported. The direct measurement of the rms betatron oscillations amplitude estimates it at about 110 nm at {beta}{sub y} {approx} 900 m. Correspondingly, at the amplitudes at the average beta function location with {beta}{sub y} {approx} 50 m is about 25 nm. Given that such direct measurements with clearly observable betatron peak were not repeatedly reproducible, one can conclude that well know 'ghost lines' are the reason for that - as they are come and go without any obvious regularity. Our analysis of these 'ghost lines' shows that (a) besides slow motion across frequencies, they also exhibit oscillatory movements with period varying from 15-20 min to few hours; (b) for the stores analysed, the lines add about factor of 2 to average - over colliding store duration - Schottky power in the betatron bands. The latter allows to estimate that they contribute about half to the previously determined the rms normalized emittance growth rate of some 0.06 {pi} mm mrad/hr. The Tevatron 'ghost lines' look very similar to infamous 'humps' recently observed in the LHC. Those 'humps' are unwanted oscillations seen repeatedly in the LHC beams (mostly in the vertical plane) and also believed to be caused by external excitations.

  11. Comparative study of two silicone hydrogel contact lenses used as bandage contact lenses after LASEK.

    Science.gov (United States)

    Gil-Cazorla, Raquel; Teus, Miguel A; Hernández-Verdejo, Jose L; De Benito-Llopis, Laura; García-González, Monsterrat

    2008-09-01

    To evaluate two silicone hydrogel contact lens materials as continuous-wear bandage contact lenses after laser-assisted subepithelial keratomileusis (LASEK). The inclusion criteria were myopia of -6.00 diopters (D) or less, astigmatism lower than -1.5 D, bilateral best-corrected visual acuity of 20/20 or better, and candidates for bilateral LASEK. The patients were randomized to be fitted with a Balafilcon A (PureVision) lens in one eye and Galyfilcon A (Acuvue Advance) in the fellow eye. Uncorrected visual acuity, corneal epithelial status, conjunctival and limbal hyperemia, lens movement, contact lens debris, and the responses to a subjective-comfort questionnaire were assessed postoperatively. The parameters were evaluated before and 1 and 5 days after the procedure. A paired Student's t-test and chi-square tests were used when appropriate. We analyzed 44 eyes of 22 consecutive patients who underwent LASEK to correct low-to-moderate myopia. The mean spherical equivalent was -3.25 +/- 2.36 D. There was no difference in conjunctival or limbal hyperemia, lens movement, uncorrected visual acuity, or epithelial healing between the two lenses at any visit. A significant difference was found in lens deposition and discomfort, which were greater with the PureVision lens 5 days postoperatively (p = 0.01 for both comparisons). PureVision and Acuvue Advance contact lenses seem to be useful as continuous wear bandage contact lenses. There is no major clinical difference between the lenses, although patients report greater comfort with Acuvue Advance.

  12. From Spheric to Aspheric Solid Polymer Lenses: A Review

    Directory of Open Access Journals (Sweden)

    Kuo-Yung Hung

    2011-01-01

    Full Text Available This paper presents a new approach in the use of MEMS technology to fabricate micro-optofluidic polymer solid lenses in order to achieve the desired profile, focal length, numerical aperture, and spot size. The resulting polymer solid lenses can be applied in optical data storage systems, imaging systems, and automated optical inspection systems. In order to meet the various needs of different applications, polymer solid lenses may have a spherical or aspherical shape. The method of fabricating polymer solid lenses is different from methods used to fabricate tunable lenses with variable focal length or needing an external control system to change the lens geometry. The current trend in polymer solid lenses is toward the fabrication of microlenses with a high numerical aperture, small clear aperture (<2 mm, and high transmittance. In this paper we focus on the use of thermal energy and electrostatic force in shaping the lens profile, including both spherical and aspherical lenses. In addition, the paper discusses how to fabricate a lens with a high numerical aperture of 0.6 using MEMS and also compares the optical characteristics of polymer lens materials, including SU-8, Norland Optical Adhesive (NOA, and cyclic olefin copolymer (COC. Finally, new concepts and applications related to micro-optofluidic lenses and polymer materials are also discussed.

  13. Investigation of biofilm formation on contact eye lenses caused by ...

    African Journals Online (AJOL)

    2014-04-20

    Apr 20, 2014 ... Objective: The objective was to investigate the biofilm-forming capacity of methicillin resistantStaphylococcus aureus (MRSA) isolated from eye lenses of infected patients. Materials and Methods: A total of 32 MRSA isolated from contact lenses of patients with ocular infections were screened for their ...

  14. Rigid Gas Permeable Contact Lenses in Hyperbaric Environments

    Science.gov (United States)

    1987-08-18

    we noted BFI with these lenses, the corneal trauma from them seemed less than in the PMMA trials by Simon and Bradley. The GPII lenses appeared...1213-1214. 6. Vinger, P. F. (Ed). Ocular Sports Injuries. Boston: Little, Brown, 1981, p. 147. 7. Betts J., Decompression Sickness and contact

  15. Are high-water-content contact lenses safe?

    Science.gov (United States)

    Bhatia, R P; Panday, Kshama; Srivastava, Rashmi; Indolia, Hitendra Singh

    2006-01-01

    We examined the role of tear secretion on contact lens water content during selection. Tear secretion was estimated using Schirmer's tests. High-water-content contact lenses compromised the tear film more than low-water-content contact lenses, hence they should not be advised in low or marginal Schirmer's test cases.

  16. 30 CFR 18.66 - Tests of windows and lenses.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tests of windows and lenses. 18.66 Section 18... Tests § 18.66 Tests of windows and lenses. (a) Impact tests. A 4-pound cylindrical weight with a 1-inch-diameter hemispherical striking surface shall be dropped (free fall) to strike the window or lens in its...

  17. Faint Submillimeter Galaxies Behind Lensing Clusters

    Science.gov (United States)

    Hsu, Li-Yen; Lauchlan Cowie, Lennox; Barger, Amy J.; Desai, Vandana; Murphy, Eric J.

    2017-01-01

    Faint submillimeter galaxies are the major contributors to the submillimeter extragalactic background light and hence the dominant star-forming population in the dusty universe. Determining how much these galaxies overlap the optically selected samples is critical to fully account for the cosmic star formation history. Observations of massive cluster fields are the best way to explore this faint submillimeter population, thanks to gravitational lensing effects. We have been undertaking a lensing cluster survey with the SCUBA-2 camera on the James Clerk Maxwell Telescope to map nine galaxy clusters, including the northern five clusters in the HST Frontier Fields program. We have also been using the Submillimeter Array and the Very Large Array to determine the accurate positions of our detected sources. Our observations have discovered high-redshift dusty galaxies with far-infrared luminosities similar to that of the Milky Way or luminous infrared galaxies. Some of these galaxies are still undetected in deep optical and near-infrared images. These results suggest that a substantial amount of star formation in even the faint submillimeter population may be hidden from rest-frame optical surveys.

  18. Engineering acoustic lenses with help from evolution

    Science.gov (United States)

    Ha˚Kansson, Andreas; Sánchez-Dehesa, José; Sánchis, Lorenzo

    2004-05-01

    Optimization engineering through evolutionary algorithms have proven to be very efficient, especially in hard problems containing a large set of optimization parameters. Like evolution this family of algorithms is able to tackle enormous complex problems with fairly simple means. Here, a simple genetic algorithm [J. H. Holland, Adaptation in Natural and Artificial Systems (Univ. of Michigan, Ann Arbor, 1975)] is used in conjunction with the multiple scattering theory [L. Sánchis et al., Phys. Rev. B 67, 035422 (2003)] to fabricate a new generation of acoustic devices based on a discrete number of cylindrical scatterers. In particular, acoustic lenses [F. Cervera et al., Phys. Rev. Lett. 88, 023902 (2002)] with flat surfaces have been designed to focus the sound in a fixed focal point for one or multiple frequencies. Each scatterer is carefully placed using the optimization method within the preset boundary conditions, to maximize the pressure contribution in the chosen focal spot. With this method acoustic lenses with very low f-numbers of the order 0.3 and with amplifications over 12 dB have been estimated using a reduced number of scatterers (~60). Preliminary results obtained from the experimental realization of the designed devices confirm our predictions.

  19. Tackling The Dragon: Investigating Lensed Galaxy Structure

    Science.gov (United States)

    Fortenberry, Alexander; Livermore, Rachael

    2018-01-01

    Galaxies have been seen to have a rapid decrease in star formation beginning at a redshift of around 1-2 up to the present day. To understand the processes underpinning this change, we need to observe the inner structure of galaxies and understand where and how the stellar mass builds up. However, at high redshifts our observable resolution is limited, which hinders the accuracy of the data. The lack of resolution at high redshift can be counteracted with the use of gravitational lensing. The magnification provided by the gravitational lens between us and the galaxies in question enables us to see extreme detail within the galaxies. To begin fine-tuning this process, we used Hubble data of Abell 370, a galaxy cluster, which lenses a galaxy know as “The Dragon” at z=0.725. With the increased detail proved by the gravitational lens we provide a detailed analysis of the galaxy’s spatially resolved star formation rate, stellar age, and masses.

  20. The theory of stochastic cosmological lensing

    Energy Technology Data Exchange (ETDEWEB)

    Fleury, Pierre; Uzan, Jean-Philippe [Institut d' Astrophysique de Paris, UMR 7095 du CNRS, 98 bis Bd Arago, 75014 Paris (France); Larena, Julien, E-mail: fleury@iap.fr, E-mail: j.larena@ru.ac.za, E-mail: uzan@iap.fr [Department of Mathematics, Rhodes University, Grahamstown 6140 (South Africa)

    2015-11-01

    On the scale of the light beams subtended by small sources, e.g. supernovae, matter cannot be accurately described as a fluid, which questions the applicability of standard cosmic lensing to those cases. In this article, we propose a new formalism to deal with small-scale lensing as a diffusion process: the Sachs and Jacobi equations governing the propagation of narrow light beams are treated as Langevin equations. We derive the associated Fokker-Planck-Kolmogorov equations, and use them to deduce general analytical results on the mean and dispersion of the angular distance. This formalism is applied to random Einstein-Straus Swiss-cheese models, allowing us to: (1) show an explicit example of the involved calculations; (2) check the validity of the method against both ray-tracing simulations and direct numerical integration of the Langevin equation. As a byproduct, we obtain a post-Kantowski-Dyer-Roeder approximation, accounting for the effect of tidal distortions on the angular distance, in excellent agreement with numerical results. Besides, the dispersion of the angular distance is correctly reproduced in some regimes.

  1. Lensing and dynamics of ultracompact bosonic stars

    Science.gov (United States)

    Cunha, Pedro V. P.; Font, José A.; Herdeiro, Carlos; Radu, Eugen; Sanchis-Gual, Nicolas; Zilhão, Miguel

    2017-11-01

    Spherically symmetric bosonic stars are one of the few examples of gravitating solitons that are known to form dynamically, via a classical process of (incomplete) gravitational collapse. As stationary solutions of the Einstein-Klein-Gordon or the Einstein-Proca theory, bosonic stars may also become sufficiently compact to develop light rings and hence mimic, in principle, gravitational-wave observational signatures of black holes (BHs). In this paper, we discuss how these horizonless ultracompact objects (UCOs) are actually distinct from BHs, both phenomenologically and dynamically. In the electromagnetic channel, the light ring associated phenomenology reveals remarkable lensing patterns, quite distinct from a standard BH shadow, with an infinite number of Einstein rings accumulating in the vicinity of the light ring, both inside and outside the latter. The strong lensing region, moreover, can be considerably smaller than the shadow of a BH with a comparable mass. Dynamically, we investigate the fate of such UCOs under perturbations, via fully nonlinear numerical simulations and observe that, in all cases, they decay into a Schwarzschild BH within a time scale of O (M ), where M is the mass of the bosonic star. Both these studies reinforce how difficult it is for horizonless UCOs to mimic BH phenomenology and dynamics, in all its aspects.

  2. GLAMER - II. Multiple-plane gravitational lensing

    Science.gov (United States)

    Petkova, Margarita; Metcalf, R. Benton; Giocoli, Carlo

    2014-12-01

    We present an extension to multiple planes of the gravitational lensing code GLAMER. The method entails projecting the mass in the observed light-cone on to a discrete number of lens planes and inverse ray-shooting from the image to the source plane. The mass on each plane can be represented as haloes, simulation particles, a projected mass map extracted form a numerical simulation or any combination of these. The image finding is done in a source-oriented fashion, where only regions of interest are iteratively refined on an initially coarse image plane grid. The calculations are performed in parallel on shared memory machines. The code is able to handle different types of analytic haloes (NFW, NSIE, power law, etc.), haloes extracted from numerical simulations and clusters constructed from semi-analytic models (MOKA). Likewise, there are several different options for modelling the source(s) which can be distributed throughout the light-cone. The distribution of matter in the light-cone can be either taken from a pre-existing N-body numerical simulations, from halo catalogues, or are generated from an analytic mass function. We present several tests of the code and demonstrate some of its applications such as generating mock images of galaxy and galaxy cluster lenses.

  3. Compound Refractive Lenses for Thermal Neutron Applications

    Energy Technology Data Exchange (ETDEWEB)

    Gary, Charles K.

    2013-11-12

    This project designed and built compound refractive lenses (CRLs) that are able to focus, collimate and image using thermal neutrons. Neutrons are difficult to manipulate compared to visible light or even x rays; however, CRLs can provide a powerful tool for focusing, collimating and imaging neutrons. Previous neutron CRLs were limited to long focal lengths, small fields of view and poor resolution due to the materials available and manufacturing techniques. By demonstrating a fabrication method that can produce accurate, small features, we have already dramatically improved the focal length of thermal neutron CRLs, and the manufacture of Fresnel lens CRLs that greatly increases the collection area, and thus efficiency, of neutron CRLs. Unlike a single lens, a compound lens is a row of N lenslets that combine to produce an N-fold increase in the refraction of neutrons. While CRLs can be made from a variety of materials, we have chosen to mold Teflon lenses. Teflon has excellent neutron refraction, yet can be molded into nearly arbitrary shapes. We designed, fabricated and tested Teflon CRLs for neutrons. We demonstrated imaging at wavelengths as short as 1.26 ? with large fields of view and achieved resolution finer than 250 μm which is better than has been previously shown. We have also determined designs for Fresnel CRLs that will greatly improve performance.

  4. The theory of stochastic cosmological lensing

    CERN Document Server

    Fleury, Pierre; Uzan, Jean-Philippe

    2015-01-01

    On the scale of the light beams subtended by small sources, e.g. supernovae, matter cannot be accurately described as a fluid, which questions the applicability of standard cosmic lensing to those cases. In this article, we propose a new formalism to deal with small-scale lensing as a diffusion process: the Sachs and Jacobi equations governing the propagation of narrow light beams are treated as Langevin equations. We derive the associated Fokker-Planck-Kolmogorov equations, and use them to deduce general analytical results on the mean and dispersion of the angular distance. This formalism is applied to random Einstein-Straus Swiss-cheese models, allowing us to: (1) show an explicit example of the involved calculations; (2) check the validity of the method against both ray-tracing simulations and direct numerical integrations of the Langevin equation. As a byproduct, we obtain a post-Kantowski-Dyer-Roeder approximation, accounting for the effect of tidal distortions on the angular distance, in excellent agree...

  5. Strong Gravitational Lensing: Blueprints for Galaxy-Cluster Core Reconstruction

    Science.gov (United States)

    Newbury, Peter Robert

    1998-11-01

    When rays of light pass by a massive object they are very slightly deflected towards the centre-of-mass of the object. If two or more diverging beams of light re-converge onto an serendipitous observer, this observer may see multiple, magnified images of the source of light. This process is known as gravitational lensing, and has been observed in several dozen spectacular cases. Based on the appearance of the lensed arcs of light, we attempt to 'invert' the lens to find the distribution of mass that will produce just such a configuration of lensed objects. In this thesis, we propose a two-stage inversion scheme. First, the distribution of mass on the deflector plane and the geometry of the source-deflector-observer optical system are established. This is done by numerically simulating the lensing of light past a parametric mass model, and interactively adjusting the handful of model parameters to match the positions of the simulated and observed lensed arcs. At the same time, this determines the magnification of the background source induced by the lensing process. The predicted magnification is then removed from the data to reveal the intrinsic, though still distorted, background distribution of light. After tracing each lensed ray back to the source plane, the data are recombined to produce a surface brightness distribution of the source. This two-stage inversion scheme produces a parametric model of the deflector and a pixelised rendering of the background source which together mimic the observed gravitationally lensed features. We test the viability of scheme itself on a well-studied collection of lensed objects in the galaxy-cluster MS 2137. Confident in the algorithm, we apply it second time to predict the distribution of mass in the galaxy-cluster MS 1455 responsible for an observed triplet of lensed arcs. Our predictions about the lens in MS 1455 make it particularly interesting, for a single background source is responsible for both tangential arcs and a

  6. Photoprotection and Extended Drug Delivery by UV Blocking Contact Lenses.

    Science.gov (United States)

    Hsu, Kuan-Hui; Chauhan, Anuj

    2016-04-01

    Extended release of photo-unstable drugs from ophthalmic inserts is not useful unless the loaded drug is protected from degradation. Because of the recent interest in extended drug delivery from contact lenses, it is critical to assess whether photo-unstable drugs can be stabilized by loading in lenses. Here, we focus on dexamethasone, which is prone to degradation and has been explored as a candidate for extended release from contact lenses for periods ranging from 10 hours to several days. Degradation rates of dexamethasone were measured in phosphate-buffered saline and after loading in contact lenses. The degradation rates were measured in a humidified, constant-temperature (32°C) chamber with controlled UV exposure. Contact lenses with various degrees of UV blocking were used to explore the relationship between degradation rates and UV exposure. It is known that vitamin E absorbs UV radiation; thus, it was loaded into the lenses to explore the feasibility of reducing the degradation rates. About 85% of dexamethasone degraded in 20 hours in non-UV blocking lenses, whereas less than 1% degraded in class 1 UV blocking lenses. Incorporation of vitamin E into the non-UV blocking lenses reduced the fractional degradation to 30%. Degradation rates in phosphate-buffered saline were significantly higher than even in non-UV blocking contact lenses. The degradation of dexamethasone can be minimized by using a UV blocking contact lens or incorporating vitamin E into a non-UV blocking lens. Vitamin E incorporation has the dual benefits of improving drug stability and release profiles.

  7. Large Scale Cleaning Telescope Mirrors with Electron Beams Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Cleaning Lenses and Mirrored Surfaces with Electrons tasks include: Development of Fractal Wand Geometries; Vacuum Chamber testing of Fractal Wand...

  8. Calcification in hydrophilic intraocular lenses associated with injection of intraocular gas.

    Science.gov (United States)

    Dhital, Anish; Spalton, David J; Goyal, Saurabh; Werner, Liliana

    2012-06-01

    To report a distinct type of calcification in hydrophilic intraocular lenses in complicated, traumatized eyes with a history of intraocular gas use. Observational case series. Three cases of hydrophilic intraocular lens (IOL) opacification confined to the pupillary area are reported from clinical practice in London, UK. Clinical details and analysis of the explanted intraocular lenses are provided with environmental scanning electron microscopy images and x-ray energy-dispersive spectroscopy results. All cases were associated with use of intraocular gas in complicated traumatized eyes, and had central areas of IOL opacification over the pupillary zone, confined to the anterior surface of the IOL. Analysis of the lenses showed the opacified areas to be composed of calcium and phosphate. The areas of opacification in all 3 hydrophilic IOLs were attributable to calcification. We postulate that intraocular gas use and the altered blood-aqueous barrier of these complicated traumatized eyes co-act to trigger secondary IOL calcification. Further experimental testing is needed to confirm this clinical association. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. A simple technique of intraocular lenses explantation for single-piece foldable lenses

    Directory of Open Access Journals (Sweden)

    Arup Bhaumik

    2017-01-01

    Full Text Available Foldable intraocular lenses (IOLs are most commonly used in modern-day cataract surgery. Explantation of these IOLs is not frequently encountered, but sometimes extreme situations may demand the same. Commonly explantation is achieved by bisecting the IOL inside the anterior chamber with a cutter and delivering the pieces out one by one. This may require corneal wound extension with associated damage and endothelial loss leading to visual deterioration. We devised a simple, innovative IOL explantation technique utilizing a modified Alcon A cartridge and snare. This can successfully refold the IOL to be explanted inside the eye and deliver it out through the same wound. The device has limitations with very thick optic lenses, multipiece, and silicon IOLs. In conclusion, we describe a simple, innovative, and reproducible technique to explant almost any single piece IOL without compromising the original surgery and yielding very satisfactory outcomes.

  10. The use of contact lenses by USAF aviators.

    Science.gov (United States)

    Tredici, T J; Flynn, W J

    1987-05-01

    Contact lenses are an alternative method to spectacles for correcting refractive errors, but the U.S. Air Force prohibits the wearing of contact lenses by all aircrew members unless medically or optically indicated (AFR 167-3). USAFSAM has a clinical contact lens study consisting of 55 individuals wearing contact lenses for eye defects such as keratoconus, aphakia, anisometropia, and other special indications. Of these 55 individuals, 33 had medical conditions affecting their vision and were unconditionally grounded. Of these individuals, 31 (18 of 19 pilots, 8 of 9 navigators, 5 of 5 other categories) were visually rehabilitated and returned to full flight status by the use of contact lenses. Hard lenses were used in 70% of the cases and soft lenses in 30%. The large number of USAF aviators required to wear spectacles and new head-borne equipment has created compatibility problems with the standard USAF aviators' spectacle. For this spectacle compatibility problem, contact lenses appear as a viable alternative. However, for wide-spread use, concerns remain about the potential aviation hazards, such as +Gz effects, bubble formation, and corneal hypoxia.

  11. [Correction of refractive errors in children with contact lenses].

    Science.gov (United States)

    Nicula, Cristina; Blidaru, M; Nicula, D

    2004-01-01

    To appreciate the indications, complications and visual outcomes in the correction of refractive errors with contact lenses at children. We studied 15 eyes from nine kids. The times prescription included: history (motivation of wearing contact lenses), ocular refraction (with cycloplegia), best corrected visual acuity, keratometry, the corneal diameter, slit lamp examination, the selection of contact lens and follow up. The age of patients varied between several months to twelve years. The refractive errors in which we used contact lenses were: aphakia--6 eyes, myopia--6 eyes, hyperopia--3 eyes. The types of contact lenses were for permanent use--8 eyes and discontinuity use--7 eyes. We didn't have any major complication. The best corrected visual acuity with contact lenses was: 0.1-0.3 at 4 eyes, 0.4-0.6 at 2 eyes and one at 7 eyes. (1) Contact lenses represent the optimal correction of anisometropia after congenital or traumatic cataract operation in children. (2) The quality of vision obtained with contact lenses represents an important factor in the prevention and treatment of amblyopia.

  12. Free and bound water in normal and cataractous human lenses.

    Science.gov (United States)

    Heys, Karl R; Friedrich, Michael G; Truscott, Roger J W

    2008-05-01

    To analyze free and total water in human normal and cataractous lenses. Thermogravimetric analysis was used to determine total water, and differential scanning calorimetry was used for free water. In normal human lenses, the total water content of the nucleus remained unchanged with age, but the state of the water altered. The ratio of free to bound water increased steadily throughout adult life. In a 20-year-old person, there was approximately one bound water molecule for each free water molecule in the lens center, whereas in a 70- to 80-year-old person, there were two free water molecules for each bound water molecule. This conversion of bound to free water does not appear to be simply a consequence of the aggregation of soluble crystallins into high molecular weight aggregates because studies with intact pig lenses, in which such processes were facilitated by heat, did not show similar changes. The region of the lens in which the barrier to diffusion develops at middle age corresponds to a transition zone in which the protein concentration is intermediate between that of the cortex and the nucleus. In cataractous lenses, the free-to-bound water ratio was not significantly different from that of age-matched normal lenses; however, total water content in the center of advanced nuclear cataractous lenses was slightly lower than in normal lenses. As the human lens ages, bound water is progressively changed to free water. Advanced nuclear cataract may be associated with lower total hydration of the lens nucleus.

  13. [Quality of life in patients wearing scleral lenses].

    Science.gov (United States)

    Picot, C; Gauthier, A-S; Campolmi, N; Delbosc, B

    2015-09-01

    To evaluate the contribution of scleral lenses in terms of improving the quality of life in the treatment of astigmatism after penetrating keratoplasty or in keratoconus. We conducted an observational retrospective study, evaluating quality of life (QOL) of patients who failed to adapt to RPG lenses, fitted with SPOT(®) scleral lenses between October 2007 and March 2011 in the University Hospital of Besançon Department of Ophthalmology. QOL was assessed before and after scleral lens adaptation with the French version of the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ 25). We included 47 patients (83 eyes) fitted with scleral lenses on one or both eyes: 56 eyes with keratoconus and 27 post-keratoplasty eyes. The average duration of wearing scleral lenses was 18±10months and the average wearing time was 14±3hours per day. The rate of participation in the survey was 86.5% (41 patients). Visual acuity in the better eye progressed from 0.68±0.46 to 0.15±0.17 logMAR at the 6th month after scleral lens adaptation (P0.05). Scleral lenses showed a significant improvement in quality of life for patients who had failed or are intolerant to conventional rigid gas permeable contact lenses. In our two main optical indications, keratoconus and keratoplasty, they represent an alternative or a step prior to surgery. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. Searches for the Standard Model Higgs boson at the Tevatron collider

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Wade C. [Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Junk, Thomas R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2016-01-01

    During Run II of the Tevatron collider, which took place from 2001 until 2011, the CDF and D0 detectors each collected approximately 10 fb -1 of collision data at a center-of-mass energy of . This dataset allowed for tests for the presence of the SM Higgs boson in the mass range 90-200 GeV in the production modes gg → H, W/ZH, vector-boson fusion, and H, with H decay modes H → , H → W+W-, H →

  15. Clinic study on silicone hydrogel contact lenses used as bandage contact lenses after LASEK surgery.

    Science.gov (United States)

    Qu, Xiao-Mei; Dai, Jin-Hui; Jiang, Zhen-Ying; Qian, Yi-Feng

    2011-01-01

    To compare the clinical performance of two types of silicon hydrogel contact lenses used as bandage lenses after LASEK surgery. A prospective, double-masked study was conducted on 42 eyes of 21 patients who received binocular LASEK surgeries. The interocular difference in spherical equivalent power was less than -1.50D. Patients were randomly assigned to wear Galyfilcon A (Lens A) bandage contact lens in one eye and Balafilcon A (Lens B) in the fellow eye after the surgery. The responses to a subjective questionnaire on comfort of wearing, corneal epithelial status, conjunctival hyperemia, limbal neovascularization, lens fitting and contact lens debris were assessed 1 and 5 days postoperatively. Corneal endothelium was assessed before and 5 days after the surgery upon bandage lens removal. There was no difference between the two groups in terms of conjunctival hyperemia, limbal neovascularization, contact lens fitting, corneal epithelial status, corneal endothelium cell density (CD) and endothelium cell size (CS) at any postoperative visit. Complaints of discomfort, including foreign body sensation, pain and intolerance were statistically more among Lens B wearers at any postoperative visit (Psilicon hydrogel lenses investigated in this study demonstrated similar clinical performance in terms of corneal responses and lens fitting. However, Lens A showed a better performance in terms of comfort of wearing and deposit resistance.

  16. The Use of Contact Lenses in Industrial Environments: An Assessment of Current Research and Policy.

    Science.gov (United States)

    Connors, Terry

    2001-01-01

    Attempts to dispel rumors concerning contact lenses and tries to supply prudent-use practices for allowing contact lenses in industry and laboratories. Discusses federal regulations that impact the use of contact lenses in industry, policy statements from medical organizations on use of contact lenses in industrial environments, and the…

  17. Finding strong lenses in CFHTLS using convolutional neural networks

    Science.gov (United States)

    Jacobs, C.; Glazebrook, K.; Collett, T.; More, A.; McCarthy, C.

    2017-10-01

    We train and apply convolutional neural networks, a machine learning technique developed to learn from and classify image data, to Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) imaging for the identification of potential strong lensing systems. An ensemble of four convolutional neural networks was trained on images of simulated galaxy-galaxy lenses. The training sets consisted of a total of 62 406 simulated lenses and 64 673 non-lens negative examples generated with two different methodologies. An ensemble of trained networks was applied to all of the 171 deg2 of the CFHTLS wide field image data, identifying 18 861 candidates including 63 known and 139 other potential lens candidates. A second search of 1.4 million early-type galaxies selected from the survey catalogue as potential deflectors, identified 2465 candidates including 117 previously known lens candidates, 29 confirmed lenses/high-quality lens candidates, 266 novel probable or potential lenses and 2097 candidates we classify as false positives. For the catalogue-based search we estimate a completeness of 21-28 per cent with respect to detectable lenses and a purity of 15 per cent, with a false-positive rate of 1 in 671 images tested. We predict a human astronomer reviewing candidates produced by the system would identify 20 probable lenses and 100 possible lenses per hour in a sample selected by the robot. Convolutional neural networks are therefore a promising tool for use in the search for lenses in current and forthcoming surveys such as the Dark Energy Survey and the Large Synoptic Survey Telescope.

  18. Fitting miniscleral contact lenses in Korean patients with keratoconus.

    Science.gov (United States)

    Kim, Sujin; Lee, Jong Soo; Park, Young Kee; Lee, Seung Uk; Park, Young Min; Lee, Jong Heon; Lee, Ji-Eun

    2017-07-01

    The aim was to evaluate the clinical results of fitting MSD miniscleral contact lenses (MSD; Happy Vision Corp, Anyang, Korea) in Korean patients with keratoconus. This report presents a retrospective case review of 38 keratoconic patients fitted with MSD lenses. Visual acuity, comfort, mean wear time, final lens parameters, relationships between sagittal depth and topographic indices, success rate with the first lens ordered and adverse events were documented. The mean logMAR visual acuity was improved from 0.85 ± 0.78 with glasses and 0.28 ± 0.29 with corneal rigid gas-permeable lenses to 0.10 ± 0.11 with miniscleral contact lenses. Ninety-seven per cent of patients found the miniscleral contact lenses to be comfortable and the mean daily wear time was 10.1 ± 2.3 hours. The mean sagittal depth was 4.70 ± 0.35 mm and there was no correlation between sagittal depth and topographic indices. An average of 3.4 trial lenses was needed to decide the ordered lens and 1.3 ordered lenses to achieve the optimal fitting. One patient discontinued the wear of the lenses after three months due to discomfort. The use of MSD miniscleral contact lenses is a good alternative for patients with keratoconus and for those who failed to respond to other types of lens rehabilitation that results in both successful visual outcome and comfort. © 2016 Optometry Australia.

  19. [History of the development of intraocular lenses].

    Science.gov (United States)

    Auffarth, G U; Apple, D J

    2001-11-01

    Even though cataract surgery has been practiced for over 2000 years, modern cataract surgery started just some 50 years ago. with the first IOL implantation by Sir Harold Ridley. The development of intraocular lenses was accompanied by great successes and disasters. With the fast development of cataract surgical techniques over the past 15 years (ECCE, Phacoemulsification, Capsulorhexis) a successful marriage between IOL-developments and surgery was established. Indication profiles for cataract surgery and IOL implantation extended to more and more patient groups. At this time classical cataract surgery is further developing into refractive intraocular lens surgery to correct higher ametropia in clear lens or phakic eyes. This development was only possible because of the improvements of surgical techniques and implants in classical cataract surgery.

  20. Microfabrication of hard x-ray lenses

    DEFF Research Database (Denmark)

    Stöhr, Frederik

    This thesis deals with the development of silicon compound refractive lenses (Si-CRLs) for shaping hard x-ray beams. The CRLs are to be fabricated using state of the art microfabrication techniques. The primary goal of the thesis work is to produce Si-CRLs with considerably increased structure...... developed. Inverse replica molding in PDMS of the CRLs was established as an effective way to circumvent the limitations AFM probes have when concave surfaces need to be characterized, e.g. due to the finite lengths of AFM probes. Four different x-ray optical components have been designed, manufactured...... of space for sample surroundings and ensure low-divergent and wide x-ray beams with narrow waists. Both results are substantial improvements to what was available at the start of this thesis work. The challenge of making x-ray objectives in silicon by interdigitation of lenslets alternately focusing...

  1. Simulating Error in Cluster Weak Lensing Tomography

    Science.gov (United States)

    Murphy, Kellen J.

    2012-01-01

    We present the results of an N-body simulation of the various sources of systematic error in constraining the dark energy equation of state via cluster weak lensing tomography. The use of tomographic techniques to constrain the dark energy equation of state parameter is a pivotal component of future large survey missions, however, the application of tomography to cosmic shear necessitates the exclusion of regions around galaxy clusters from analysis. We therefore test the applicability tomography to cluster-induced shear as a secondary, complementary sample through which estimates of the dark energy e.o.s. parameter can be made. Furthermore, we demonstrate the application of this technique to a test sample of 10 massive galaxy clusters imaged by the Hubble Space Telescope.

  2. Study of the production of the Σ b with the CDF detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Calancha Paredes, Constantino [Complutense Univ. of Madrid (Spain)

    2011-02-01

    The composition of matter is a topic in which the man has been interested throughout History. Since the introduction of the atom by Democritus in the 5th century BC until the establishment of the Standard Model, our successful theory that contains our current knowledge on the matter and their interactions, it has come a long way trying to solve this fundamental question. The efforts of many of the greatest minds to perform crucial experiments and develop theoretical models have helped to get deeper insight into the origin of the matter. Today we know that indivisible atoms postulated by Democritus are no longer true, and they are actually composed of a nucleus made of protons and neutrons (nucleons) with orbiting electrons through electromagnetic interactions. Also the nucleons are not fundamental particles but are composed of more fundamental ones called quarks. According to the present state of our knowledge, matter is composed of two types of particles: quarks and leptons. Leptons are believed to be fundamental particles and can occur freely in nature. Quarks are also fundamental particles, and there are no free in nature, but are confined to form hadrons. The hadrons may consist of a quark and an antiquark (mesons) or three quarks or three antiquarks (baryons). These quarks and leptons interact through the exchange of particles called bosons. Figure 1.1 summary the elementary particles in the Standard Model. Despite its enormous success we know that the Standard Model is incomplete. Some of the issues left unresolved by the Standard Model are the mechanism for electroweak symmetry breaking, the mass spectrum of the Standard Model or that the Universe is much more matter than antimatter. That means that it should exist a more general theory which include the Standard Model as a valid approximation for low energy. This more general theory must give answers to the previous unresolved questions. Accumulate more experimental information is crucial to get a deeper

  3. Like-Sign Dileptons at the Fermilab Tevatron Revisited in the Light of the HERA High-$Q^2$ Anomaly

    CERN Document Server

    Choudhury, D; Choudhury, Debajyoti; Raychaudhuri, Sreerup

    1997-01-01

    We re-examine like-sign dilepton signals at the Fermilab Tevatron assuming that the excess high-$Q^2$ events recently seen at HERA are due to the production and decay of squarks of $R$-parity-violating supersymmetry. For gluinos in the mass range of 200--350 GeV, the like-sign dilepton signal can help to make the crucial distinction between the most favoured squark explanation and other proposed solutions.

  4. Combination of Tevatron searches for the standard model Higgs boson in the W+W- decay mode

    NARCIS (Netherlands)

    Aaltonen, T.; et al., [Unknown; Ancu, L.S.; de Jong, S.J.; Filthaut, F.; Galea, C.F.; Hegeman, J.G.; Houben, P.; Meijer, M.M.; Svoisky, P.; van den Berg, P.J.

    2010-01-01

    We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb(-1) of p (p) over bar collisions at root s = 1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background

  5. Coherent Production of Pions and Rho Mesons in Neutrino Charged Current Interactions on Neon Nuclei at the Fermilab Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Willocq, Stéphane [Tufts Univ., Medford, MA (United States)

    1992-04-30

    The coherent production of single pions and $\\rho$ mesons in charged current interactions of neutrinos and antineutrinos on neon nuclei has been studied. The data were obtained using the Fermilab 15-foot Bubble Chamber, filled with a heavy Ne- $H_2$ mixture and exposed to the Quadrupole Triplet neutrino beam produced by 800 Ge V protons from the Tevatron. The average beam energy was 86 Ge V. In a sample of 330 000 frames, 1032 two-prong $\

  6. Measurement of the top quark mass using dilepton events and a neutrino weighting algorithm with the DOe experiment at the Tevatron (Run II)

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.

    2007-07-01

    Several measurements of the top quark mass in the dilepton final states with the DOe experiment are presented. The theoretical and experimental properties of the top quark are described together with a brief introduction of the Standard Model of particle physics and the physics of hadron collisions. An overview over the experimental setup is given. The Tevatron at Fermilab is presently the highest-energy hadron collider in the world with a center-of-mass energy of 1.96 TeV. There are two main experiments called CDF and DOe, A description of the components of the multipurpose DOe detector is given. The reconstruction of simulated events and data events is explained and the criteria for the identification of electrons, muons, jets, and missing transverse energy is given. The kinematics in the dilepton final state is underconstraint. Therefore, the top quark mass is extracted by the so-called Neutrino Weighting method. This method is introduced and several different approaches are described, compared, and enhanced. Results for the international summer conferences 2006 and winter 2007 are presented. The top quark mass measurement for the combination of all three dilepton channels with a dataset of 1.05 1/fb yields: mtop=172.5{+-}5.5 (stat.) {+-} 5.8 (syst.) GeV. This result is presently the most precise top quark mass measurement of the DOe experiment in the dilepton chann el. It entered the top quark mass wold average from March 2007. (orig.)

  7. X-Ray Properties of Lensing-Selected Clusters

    Science.gov (United States)

    Paterno-Mahler, Rachel; Sharon, Keren; Bayliss, Matthew; McDonald, Michael; Gladders, Michael; Johnson, Traci; Dahle, Hakon; Rigby, Jane R.; Whitaker, Katherine E.; Florian, Michael; Wuyts, Eva

    2017-08-01

    I will present preliminary results from the Michigan Swift X-ray observations of clusters from the Sloan Giant Arcs Survey (SGAS). These clusters were lensing selected based on the presence of a giant arc visible from SDSS. I will characterize the morphology of the intracluster medium (ICM) of the clusters in the sample, and discuss the offset between the X-ray centroid, the mass centroid as determined by strong lensing analysis, and the BCG position. I will also present early-stage work on the scaling relation between the lensing mass and the X-ray luminosity.

  8. Strong deflection lensing by a Lee-Wick black hole

    Science.gov (United States)

    Zhao, Shan-Shan; Xie, Yi

    2017-11-01

    We study strong deflection gravitational lensing by a Lee-Wick black hole, which is a non-singular black hole generated by a high derivative modification of Einstein-Hilbert action. The strong deflection lensing is expected to produce a set of relativistic images very closed to the event horizon of the black hole. We estimate its observables for the supermassive black hole in our Galactic center. It is found that the Lee-Wick black hole can be distinguished from the Schwarzschild black hole via such lensing effects when the UV scale is not very large, but the requiring resolution is much higher than current capability.

  9. [Implantation of intraocular lenses. Bullous keratopathy in pseudophakos].

    Science.gov (United States)

    Alberth, B

    1982-09-01

    The author presents his views on the implantation of intraocular lenses, in connection with two pseudophakic bullous keratopathy cases. There is no medical indication for implantation. The question is whether the most important function of the eye, object vision, may be risked in order to avoid aniseikonia or to restore binocular vision? Knowing that vision can be restored with glasses or contact lenses, is it ethical to induce more or less severe postoperative complications by means of intraocular lenses? In view of the considerable success often achieved immediately after the operation, complications which may not arise years later should also be taken into consideration.

  10. Inhibition of Lens Photodamage by UV-Absorbing Contact Lenses

    Science.gov (United States)

    Malone, James P.; Townsend, R. Reid

    2011-01-01

    Purpose. To determine whether class 1 UV-blocking contact lenses protect against UVB radiation–induced damage in a human lens epithelial cell line (HLE B-3) and postmortem human lenses using a proteomics approach. Methods. HLE B-3 cells were exposed to 6.4 mW/cm2 UVB radiation at 302 nm for 2 minutes (768 mJ/cm2) with or without covering by senofilcon A class 1 UV-blocking contact lenses or lotrafilcon A non–UV-blocking (lotrafilcon A has some UV-blocking ability, albeit minimal) contact lenses. Control cells were not exposed to UVB radiation. Four hours after treatment, cells were analyzed by two-dimensional difference gel electrophoresis and tandem mass spectrometry, and changes in protein abundance were quantified. F-actin and microtubule cytoskeletons were examined by fluorescence staining. In addition, human donor lenses were exposed to UVB radiation at 302 nm for 4 minutes (1536 mJ/cm2). Cortical and epithelial cell proteins were scraped from lens surfaces and subjected to the same protein analyses. Results. Senofilcon A lenses were beneficial for protecting HLE B-3 cells against UVB radiation–induced changes in caldesmon 1 isoform, lamin A/C transcript variant 1, DEAD (Asp-Glu-Ala-Asp) box polypeptide, β-actin, glyceraldehyde 3-phosphate dehydrogenase (G3PDH), annexin A2, triose phosphate isomerase, and ubiquitin B precursor. These contact lenses also prevented actin and microtubule cytoskeleton changes typically induced by UVB radiation. Conversely, non–UV-blocking contact lenses were not protective. UVB-irradiated human lenses showed marked reductions in αA-crystallin, αB-crystallin, aldehyde dehydrogenase 1, βS-crystallin, βB2-crystallin, and G3PDH, and UV-absorbing contact lenses significantly prevented these alterations. Conclusions. Senofilcon A class 1 UV-blocking contact lenses largely prevented UVB-induced changes in protein abundance in lens epithelial cells and in human lenses. PMID:21873653

  11. Computer-Aided Design for Electron Microscopy

    Czech Academy of Sciences Publication Activity Database

    Lencová, Bohumila

    2004-01-01

    Roč. 6, č. 1 (2004), s. 51-53 ISSN 1439-4243 Institutional research plan: CEZ:AV0Z2065902 Keywords : magnetic electron lenses * accuracy of computation * computer-aided design Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  12. Finding the Higgs boson of the standard model in the channel ZH → e+e-b$\\bar{b}$ with the D0 detector at the Tevatron; Recherche du boson de Higgs du nideke standard dans le canal ZH → e+e-b$\\bar{b}$ avec le detecteur DØ aupres du Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Calpas, Betty Constante [Univ. of the Mediterranean, Marseille (France)

    2010-06-11

    The organization of this thesis consists of three main ideas: the first presents the theoretical framework and experimental, as well as objects used in the analysis and the second relates to the various work tasks of service that I performed on the calorimeter, and the third is the search for the Higgs boson in the channel ZH → e+e-b$\\bar{b}$. Thus, this thesis has the following structure: Chapter 1 is an introduction to the standard model of particle physics and the Higgs mechanism; Chapter 2 is an overview of the complex and the acceleration of the Tevatron at Fermilab DØ detector; Chapter 3 is an introduction to physical objects used in this thesis; Chapter 4 presents the study made on correcting the energy measured in the calorimeter; Chapter 5 describes the study of certification of electrons in the calorimeter; Chapter 6 describes the study of certification of electrons in the intercryostat region of calorimeter; Chapter 7 Detailed analysis on the search for Higgs production in the channel ZH → e+e-b$\\bar{b}$; and Chapter 8 presents the final results of the calculations of upper limits to the production cross section of the Higgs boson on a range of low masses.

  13. Combination of measurements of the top-quark pair production cross section from the Tevatron Collider

    Science.gov (United States)

    Aaltonen, T.; Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Askew, A.; Atkins, S.; Auerbach, B.; Augsten, K.; Aurisano, A.; Avila, C.; Azfar, F.; Badaud, F.; Badgett, W.; Bae, T.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barbaro-Galtieri, A.; Barberis, E.; Baringer, P.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartlett, J. F.; Bartos, P.; Bassler, U.; Bauce, M.; Bazterra, V.; Bean, A.; Bedeschi, F.; Begalli, M.; Behari, S.; Bellantoni, L.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Bhatti, A.; Bland, K. R.; Blazey, G.; Blessing, S.; Bloom, K.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brandt, A.; Brandt, O.; Brigliadori, L.; Brock, R.; Bromberg, C.; Bross, A.; Brown, D.; Brucken, E.; Bu, X. B.; Budagov, J.; Budd, H. S.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buszello, C. P.; Butti, P.; Buzatu, A.; Calamba, A.; Camacho-Pérez, E.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Casey, B. C. K.; Castilla-Valdez, H.; Castro, A.; Catastini, P.; Caughron, S.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Cho, S. W.; Choi, S.; Chokheli, D.; Choudhary, B.; Cihangir, S.; Claes, D.; Clark, A.; Clarke, C.; Clutter, J.; Convery, M. E.; Conway, J.; Cooke, M.; Cooper, W. E.; Corbo, M.; Corcoran, M.; Cordelli, M.; Couderc, F.; Cousinou, M.-C.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; Cutts, D.; Das, A.; d'Ascenzo, N.; Datta, M.; Davies, G.; de Barbaro, P.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Demortier, L.; Deninno, M.; Denisov, D.; Denisov, S. P.; D'Errico, M.; Desai, S.; Deterre, C.; DeVaughan, K.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dittmann, J. R.; Dominguez, A.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Ebina, K.; Edgar, R.; Edmunds, D.; Elagin, A.; Ellison, J.; Elvira, V. D.; Enari, Y.; Erbacher, R.; Errede, S.; Esham, B.; Evans, H.; Evdokimov, V. N.; Farrington, S.; Feng, L.; Ferbel, T.; Fernández Ramos, J. P.; Fiedler, F.; Field, R.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Flanagan, G.; Forrest, R.; Fortner, M.; Fox, H.; Franklin, M.; Freeman, J. C.; Frisch, H.; Fuess, S.; Funakoshi, Y.; Galloni, C.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Garfinkel, A. F.; Garosi, P.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gerberich, H.; Gerchtein, E.; Gershtein, Y.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Ginther, G.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Golovanov, G.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Grinstein, S.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grosso-Pilcher, C.; Group, R. C.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Guimaraes da Costa, J.; Gutierrez, G.; Gutierrez, P.; Hahn, S. R.; Haley, J.; Han, J. Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, M.; Harel, A.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hauptman, J. M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Hong, Z.; Hopkins, W.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A. S.; Ivanov, A.; Jabeen, S.; Jaffré, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E. J.; Jeong, M. S.; Jesik, R.; Jiang, P.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K. K.; Joshi, J.; Jun, S. Y.; Jung, A. W.; Junk, T. R.; Juste, A.; Kajfasz, E.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Karmanov, D.; Kasmi, A.; Kato, Y.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. H.; Kim, S. B.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Knoepfel, K.; Kohli, J. M.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kozelov, A. V.; Kraus, J.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kumar, A.; Kupco, A.; Kurata, M.; Kurča, T.; Kuzmin, V. A.; Laasanen, A. T.; Lammel, S.; Lammers, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lebrun, P.; Lee, H. S.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J. D.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Limosani, A.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipeles, E.; Lipton, R.; Lister, A.; Liu, H.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lucchesi, D.; Lucà, A.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A. L.; Lys, J.; Lysak, R.; Maciel, A. K. A.; Madar, R.; Madrak, R.; Maestro, P.; Magaña-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V. L.; Manca, G.; Manousakis-Katsikakis, A.; Mansour, J.; Marchese, L.; Margaroli, F.; Marino, P.; Martínez-Ortega, J.; Martínez, M.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McGivern, C. L.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Mesropian, C.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N. K.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Nett, J.; Neu, C.; Neustroev, P.; Nguyen, H. T.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Osta, J.; Pagliarone, C.; Pal, A.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parashar, N.; Parihar, V.; Park, S. K.; Parker, W.; Partridge, R.; Parua, N.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.-A.; Podstavkov, V. M.; Pondrom, L.; Popov, A. V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Ranjan, N.; Ratoff, P. N.; Razumov, I.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodriguez, T.; Rolli, S.; Rominsky, M.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sajot, G.; Sakumoto, W. K.; Sakurai, Y.; Sánchez-Hernández, A.; Sanders, M. P.; Santi, L.; Santos, A. S.; Sato, K.; Savage, G.; Saveliev, V.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schmidt, E. E.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S. Z.; Shary, V.; Shaw, S.; Shchukin, A. A.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Skubic, P.; Slattery, P.; Sliwa, K.; Smirnov, D.; Smith, J. R.; Snider, F. D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; St. Denis, R.; Stancari, M.; Stark, J.; Stentz, D.; Stoyanova, D. A.; Strauss, M.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V. V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.-T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Vázquez, F.; Velev, G.; Vellidis, C.; Verkheev, A. Y.; Vernieri, C.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vilanova, D.; Vilar, R.; Vizán, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wahl, H. D.; Wallny, R.; Wang, M. H. L. S.; Wang, S. M.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W. C.; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Williams, M. R. J.; Wilson, G. W.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfe, H.; Wood, D. R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yeh, G. P.; Yi, K.; Yin, H.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S. W.; Yu, G. B.; Yu, I.; Yu, J. M.; Zanetti, A. M.; Zeng, Y.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.; CDF Collaboration

    2014-04-01

    We combine six measurements of the inclusive top-quark pair (tt ¯) production cross section (σtt ¯) from data collected with the CDF and D0 detectors at the Fermilab Tevatron with proton-antiproton collisions at √s =1.96 TeV. The data correspond to integrated luminosities of up to 8.8 fb-1. We obtain a value of σtt ¯=7.60±0.41 pb for a top-quark mass of mt=172.5 GeV. The contributions to the uncertainty are 0.20 pb from statistical sources, 0.29 pb from systematic sources, and 0.21 pb from the uncertainty on the integrated luminosity. The result is in good agreement with the standard model expectation of 7.35-0.33+0.28 pb at next-to-next-to-leading order and next-to-next-to leading logarithms in perturbative QCD.

  14. Search for super symmetry at the Tevatron using the trilepton signature

    Energy Technology Data Exchange (ETDEWEB)

    Dube, Sourabh Shishir [Rutgers Univ., New Brunswick, NJ (United States)

    2008-10-01

    This dissertation describes a search for the associated production of the supersymmetric particles, the chargino and the neutralino, through their R-parity conserving decays to three leptons and missing energy. This search is carried out using the data collected at the CDF experiment at the Tevatron √s = 1.96 TeV p$\\bar{p}$ collider at Fermilab. The results are obtained by combining five independent channels with varying signal to background ratio. Overall, a total of 6.4 ± 1.1 background events from standard model processes and 11.4 ± 1.1 signal events for a particular choice of mSUGRA model parameters are expected. The observation of 7 events in data is consistent with the standard model background expectation, and the mSUGRA model is constrained. Limits are set on the cross section of Chargino-Neutralino pair production, and a limit on the mass of the chargino is extracted. A method of obtaining model-independent results is also discussed.

  15. Combination of the top-quark mass measurements from the Tevatron collider

    CERN Document Server

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Gutierrez, P.; Hagopian, S.; Hahn, S.R.; Haley, J.; Halkiadakis, E.; Hamaguchi, A.; Han, J.Y.; Han, L.; Happacher, F.; Hara, K.; Harder, K.; Hare, D.; Hare, M.; Harel, A.; Harr, R.F.; Hatakeyama, K.; Hauptman, J.M.; Hays, C.; Hays, J.; Head, T.; Hebbeker, T.; Heck, M.; Hedin, D.; Hegab, H.; Heinrich, J.; Heinson, A.P.; Heintz, U.; Hensel, C.; Heredia-de La Cruz, I.; Herndon, M.; Herner, K.; Hesketh, G.; Hewamanage, S.; Hildreth, M.D.; Hirosky, R.; Hoang, T.; Hobbs, J.D.; Hocker, A.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Hopkins, W.; Horn, D.; Hou, S.; Howley, I.; Hubacek, Z.; Hughes, R.E.; Hurwitz, M.; Husemann, U.; Hussain, N.; Hussein, M.; Huston, J.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Introzzi, G.; Iori, M.; Ito, A.S.; Ivanov, A.; Jabeen, S.; Jaffre, M.; James, E.; Jang, D.; Jayasinghe, A.; Jayatilaka, B.; Jeon, E.J.; Jeong, M.S.; Jesik, R.; Jindariani, S.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jones, M.; Jonsson, P.; Joo, K.K.; Joshi, J.; Jun, S.Y.; Jung, A.W.; Junk, T.R.; Juste, A.; Kaadze, K.; Kajfasz, E.; Kamon, T.; Karchin, P.E.; Karmanov, D.; Kasmi, A.; Kasper, P.A.; Kato, Y.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Ketchum, W.; Keung, J.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y.N.; Khotilovich, V.; Kilminster, B.; Kim, D.H.; Kim, H.S.; Kim, J.E.; Kim, M.J.; Kim, S.B.; Kim, S.H.; Kim, Y.J.; Kim, Y.K.; Kimura, N.; Kirby, M.; Kiselevich, I.; Klimenko, S.; Knoepfel, K.; Kohli, J.M.; Kondo, K.; Kong, D.J.; Konigsberg, J.; Kotwal, A.V.; Kozelov, A.V.; Kraus, J.; Kreps, M.; Kroll, J.; Krop, D.; Kruse, M.; Krutelyov, V.; Kuhr, T.; Kulikov, S.; Kumar, A.; Kupco, A.; Kurata, M.; Kurca, T.; Kuzmin, V.A.; Kwang, S.; Laasanen, A.T.; Lami, S.; Lammel, S.; Lammers, S.; Lancaster, M.; Lander, R.L.; Landsberg, G.; Lannon, K.; Lath, A.; Latino, G.; Lebrun, P.; LeCompte, T.; Lee, E.; Lee, H.S.; Lee, H.S.; Lee, J.S.; Lee, S.W.; Lee, W.M.; Lee, S.W.; Lei, X.; Lellouch, J.; Leo, S.; Leone, S.; Lewis, J.D.; Li, H.; Li, L.; Li, Q.Z.; Lim, J.K.; Limosani, A.; Lin, C.J.; Lincoln, D.; Lindgren, M.; Linnemann, J.; Lipaev, V.V.; Lipeles, E.; Lipton, R.; Lister, A.; Litvintsev, D.O.; Liu, C.; Liu, H.; Liu, H.; Liu, Q.; Liu, T.; Liu, Y.; Lobodenko, A.; Lockwitz, S.; Loginov, A.; Lokajicek, M.; Lopes de Sa, R.; Lubatti, H.J.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Luna-Garcia, R.; Lungu, G.; Lyon, A.L.; Lys, J.; Lysak, R.; Maciel, A.K.A.; Madar, R.; Madrak, R.; Maeshima, K.; Maestro, P.; Magana-Villalba, R.; Malik, S.; Malik, S.; Malyshev, V.L.; Manca, G.; Manousakis-Katsikakis, A.; Maravin, Y.; Margaroli, F.; Marino, C.; Martinez, M.; Martinez-Ortega, J.; Mastrandrea, P.; Matera, K.; Mattson, M.E.; Mazzacane, A.; Mazzanti, P.; McCarthy, R.; McFarland, K.S.; McGivern, C.L.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Meijer, M.M.; Melnitchouk, A.; Menezes, D.; Mercadante, P.G.; Merkin, M.; Meyer, A.; Meyer, J.; Miao, T.; Miconi, F.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Mondal, N.K.; Mondragon, M.N.; Moon, C.S.; Moore, R.; Morello, M.J.; Morlock, J.; Movilla Fernandez, P.; Mukherjee, A.; Mulhearn, M.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nagy, E.; Naimuddin, M.; Nakano, I.; Napier, A.; Narain, M.; Nayyar, R.; Neal, H.A.; Negret, J.P.; Nett, J.; Neu, C.; Neubauer, M.S.; Neustroev, P.; Nielsen, J.; Nodulman, L.; Noh, S.Y.; Norniella, O.; Nunnemann, T.; Oakes, L.; Oh, S.H.; Oh, Y.D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Orduna, J.; Ortolan, L.; Osman, N.; Osta, J.; Padilla, M.; Pagan Griso, S.; Pagliarone, C.; Pal, A.; Palencia, E.; Papadimitriou, V.; Paramonov, A.A.; Parashar, N.; Parihar, V.; Park, S.K.; Partridge, R.; Parua, N.; Patrick, J.; Patwa, A.; Pauletta, G.; Paulini, M.; Paus, C.; Pellett, D.E.; Penning, B.; Penzo, A.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Petroff, P.; Phillips, T.J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pleier, M.A.; Podesta-Lerma, P.L.M.; Podstavkov, V.M.; Pondrom, L.; Popov, A.V.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prewitt, M.; Price, D.; Prokopenko, N.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Qian, J.; Quadt, A.; Quinn, B.; Rahaman, A.; Ramakrishnan, V.; Rangel, M.S.; Ranjan, K.; Ranjan, N.; Ratoff, P.N.; Razumov, I.; Redondo, I.; Renkel, P.; Renton, P.; Rescigno, M.; Riddick, T.; Rimondi, F.; Ripp-Baudot, I.; Ristori, L.; Rizatdinova, F.; Robson, A.; Rodrigo, T.; Rodriguez, T.; Rogers, E.; Rolli, S.; Rominsky, M.; Roser, R.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Safonov, A.; Sajot, G.; Sakumoto, W.K.; Sakurai, Y.; Salcido, P.; Sanchez-Hernandez, A.; Sanders, M.P.; Santi, L.; Santos, A.S.; Sato, K.; Savage, G.; Saveliev, V.; Savoy-Navarro, A.; Sawyer, L.; Scanlon, T.; Schamberger, R.D.; Scheglov, Y.; Schellman, H.; Schlabach, P.; Schlobohm, S.; Schmidt, A.; Schmidt, E.E.; Schwanenberger, C.; Schwarz, T.; Schwienhorst, R.; Scodellaro, L.; Scribano, A.; Scuri, F.; Seidel, S.; Seiya, Y.; Sekaric, J.; Semenov, A.; Severini, H.; Sforza, F.; Shabalina, E.; Shalhout, S.Z.; Shary, V.; Shaw, S.; Shchukin, A.A.; Shears, T.; Shepard, P.F.; Shimojima, M.; Shivpuri, R.K.; Shochet, M.; Shreyber-Tecker, I.; Simak, V.; Simonenko, A.; Sinervo, P.; Skubic, P.; Slattery, P.; Sliwa, K.; Smirnov, D.; Smith, J.R.; Smith, K.J.; Snider, F.D.; Snow, G.R.; Snow, J.; Snyder, S.; Soha, A.; Soldner-Rembold, S.; Song, H.; Sonnenschein, L.; Sorin, V.; Soustruznik, K.; Squillacioti, P.; St. Denis, R.; Stancari, M.; Stark, J.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Stoyanova, D.A.; Strauss, M.; Strologas, J.; Strycker, G.L.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Suter, L.; Svoisky, P.; Takahashi, M.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P.K.; Thom, J.; Thome, J.; Thompson, G.A.; Thomson, E.; Titov, M.; Toback, D.; Tokar, S.; Tokmenin, V.V.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, Y.T.; Tschann-Grimm, K.; Tsybychev, D.; Tuchming, B.; Tully, C.; Ukegawa, F.; Uozumi, S.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; W.van Leeuwen, M.; Varelas, N.; Varganov, A.; Varnes, E.W.; Vasilyev, I.A.; Vazquez, F.; Velev, G.; Vellidis, C.; Verdier, P.; Verkheev, A.Y.; Vertogradov, L.S.; Verzocchi, M.; Vesterinen, M.; Vidal, M.; Vila, I.; Vilanova, D.; Vilar, R.; Vizan, J.; Vogel, M.; Vokac, P.; Volpi, G.; Wagner, P.; Wagner, R.L.; Wahl, H.D.; Wakisaka, T.; Wallny, R.; Wang, M.H.L.S.; Wang, S.M.; Warburton, A.; Warchol, J.; Waters, D.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Wester, W.C., III; White, A.; Whiteson, D.; Wick, F.; Wicke, D.; Wicklund, A.B.; Wicklund, E.; Wilbur, S.; Williams, H.H.; Williams, M.R.J.; Wilson, G.W.; Wilson, J.S.; Wilson, P.; Winer, B.L.; Wittich, P.; Wobisch, M.; Wolbers, S.; Wolfe, H.; Wood, D.R.; Wright, T.; Wu, X.; Wu, Z.; Wyatt, T.R.; Xie, Y.; Yamada, R.; Yamamoto, K.; Yamato, D.; Yang, S.; Yang, T.; Yang, U.K.; Yang, W.C.; Yang, Y.C.; Yao, W.M.; Yasuda, T.; Yatsunenko, Y.A.; Ye, W.; Ye, Z.; Yeh, G.P.; Yin, H.; Yi, K.; Yip, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Youn, S.W.; Yu, G.B.; Yu, I.; Yu, J.M.; Yu, S.S.; Yun, J.C.; Zanetti, A.; Zeng, Y.; Zennamo, J.; Zhao, T.; Zhao, T.G.; Zhou, B.; Zhou, C.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; Zucchelli, S.

    2012-01-01

    The top quark is the heaviest known elementary particle, with a mass about twice the mass of the $W$ and $Z$ bosons of the weak interaction, and about 40 times larger than the mass of its isospin partner, the bottom quark. It decays almost 100% of the time to a $W$ boson and a bottom quark, and the $W$ boson then decays to a lepton and a neutrino or to a quark-antiquark pair. Using top-antitop pairs at the Tevatron proton-antiproton collider, the CDF and {\\dzero} collaborations have measured the top quark's mass in different decay channels for integrated luminosities of up to 5.8 fb$^{-1}$. This paper reports on a combination of these measurements that results in a more precise value of the mass than any individual decay channel can provide. It describes the treatment of the systematic uncertainties and their correlations. The mass value determined is $173.18 \\pm 0.56({\\rm stat}) \\pm 0.75({\\rm syst})$ GeV or $173.18 \\pm 0.94$ GeV, which has a precision of $\\pm 0.54%$, making the mass of the top quark the most...

  16. A search for z boson pair production at the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, Chad Ryan [Univ. of Maryland, College Park, MD (United States)

    2007-01-01

    This dissertation describes a search for Z/γ* boson pair production decaying into μμμμ, μμee, and eeee final states with approximately 1 fb-1 of data at the Fermilab Tevatron Collider at √s = 1.96 TeV. The small cross section times branching ratio for each channel mandated a thorough study of the acceptance and efficiencies. After optimization, 1.7 ± 0.1 events are expected for Standard Model production with a background of 0.13 ± 0.03 events. One event was found in the μμee channel. A cross section limit of 4.4 pb is determined at a 95% confidence level for Standard Model production. Additionally, one parameter and two parameter 95% C.L. limits are found for the anomalous neutral trilinear gauge couplings ZZZ* and ZZγ*. The one parameter 95% C.L. coupling limits with a form factor scale of 1.2 TeV are: -0.28 < f$Z\\atop{40}$ < 0.28, -0.31 < f$Z\\atop{50}$ < 0.29, -0.26 < f$γ\\atop{40}$ < 0.26, and -0.30 < f$γ\\atop{50}$ < 0.28.

  17. Impact of the A48 collimator on the Tevatron B0 dipoles

    CERN Document Server

    Nicolas, L Y

    2003-01-01

    To protect the CDF detector components in an event of an abort kicker prefire (AKP) in the Tevatron, a new collimator is to be installed at the A48 location during the summer 2003 shutdown. Detailed calculations have shown that this 0.5-m long ''single L-shape'' steel collimator will intercept a bunch of protons when such an incident occurs, providing reliable protection of the CDF main detector at an AKP. It will also mitigate the backgrounds induced by elastic beam-gas interactions upstream of B0. Although the Roman Pot detectors downstream of the A48 collimator will see an increased background, the amount of radiation they will receive either resulting from beam halo interactions in the collimator or during an AKP will not damage their sensitive parts. Secondaries resulting from beam halo interactions with the A48 collimator do not noticeably affect the downstream dipoles. The case of an AKP is quite different. As opposed to halo hits in the ''single-L shape'' unit (around 10 sup 5 p/s), a bunch lost on A4...

  18. Search for the Standard Model Higgs Boson in associated production with w boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Xu [Univ. of Michigan, Ann Arbor, MI (United States)

    2009-11-01

    A search for the Standard Model Higgs boson in proton-antiproton collisions with center-of-mass energy 1.96 TeV at the Tevatron is presented in this dissertation. The process of interest is the associated production of W boson and Higgs boson, with the W boson decaying leptonically and the Higgs boson decaying into a pair of bottom quarks. The dataset in the analysis is accumulated by the D0 detector from April 2002 to April 2008 and corresponding to an integrated luminosity of 2.7 fb-1. The events are reconstructed and selected following the criteria of an isolated lepton, missing transverse energy and two jets. The D0 Neural Network b-jet identification algorithm is further used to discriminate b jets from light jets. A multivariate analysis combining Matrix Element and Neural Network methods is explored to improve the Higgs boson signal significance. No evidence of the Higgs boson is observed in this analysis. In consequence, an observed (expected) limit on the ratio of σ (p$\\bar{p}$ → WH) x Br (H → b$\\bar{b}$) to the Standard Model prediction is set to be 6.7 (6.4) at 95% C.L. for the Higgs boson with a mass of 115 GeV.

  19. A Next-to-Leading Order QCD Analysis of Neutrino - Iron Structure Functions at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Seligman, William Glenn [Nevis Labs, Columbia U.

    1997-01-01

    Nucleon structure functions measured in neutrino-iron and antineutrinoiron charged-current interactions are presented. The data were taken in two high-energy high-statistics runs by the LAB-E detector at the Fermilab Tevatron. Structure functions are extracted from a sample of 950,000 neutrino and 170,000 antineutrino events with neutrino energies from 30 to 360 Ge V. The structure functions $F_2$ and $xF_3$ are compared with the the predictions of perturbative Quantum Chromodynamics (PQCD). The combined non-singlet and singlet evolution in the context of PQCD gives NL0(4) . 2 value of $\\Lambda^{NLO,(4)}_{\\overline MS}$ = 337 ± 28 (exp.) MeV, which corresponds to $\\alpha_s$ ($M^2_z$) = 0.119 ± 0.002 (exp.) ± 0.004 (theory), and with a gluon distribution given by $xG(x,Q^2_0 = 5 GeV^2$ ) = (2.22±0.34) x ($1-x)^{4.65 \\pm 0.68}$

  20. SVX4: A New Deep-Submicron Readout IC for the Tevatron Collider at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Krieger, B.; Alfonsi, S.; Bacchetta, N.; Centro, S.; Christofek, L.; Garcia-Sciveres, M.; Haber, C.; Hanagaki, K.; Hoff, J.; Johnson, M.; vonderLippe, H.; Lujan, P.; Mandelli, E.; Meng, G.; Nomerotski, A.; Pellet, D.; Rapidis, P.; Utes, M.; Walder, J.-P.; Weber, M.; Wester, W.; /LBL, Berkeley /Padua U. /INFN, Padua /Kansas U. /Fermilab /UC,

    2003-10-01

    SVX4 is the new silicon strip readout IC designed to meet the increased radiation tolerance requirements for Run IIb at the Tevatron collider. Devices have been fabricated, tested, and approved for production. The SVX4 design is a technology migration of the SVX3D design currently in use by CDF. Whereas SVX3D was fabricated in a 0.8 {micro}m radiation-hard process, SVX4 was fabricated in a standard 0.25 {micro}m mixed-signal CMOS technology using the ''radiation tolerant by design'' transistor topologies devised by the RD-49 collaboration. The specific cell layouts include digital cells developed by the ATLAS Pixel group, and full-custom analog blocks. Unlike its predecessors, the new design also includes the necessary features required for generic use by both the CDF and D0 experiments at Fermilab. Performance of the IC includes >20 MRad total dose tolerance, and {approx}2000 e-rms equivalent input noise charge with 40 pF input capacitance, when sampled at 132 ns period with an 80 ns preamp risetime. At the nominal digitize/readout rate of 106/53 MHz, the 9 mm x 6.3 mm die dissipates {approx}2 mW/channel average at 2.5 V. A review of typical operation, details of the design conversion process, and performance measurements are covered.

  1. SVX4 a new deep submicron readout IC for the Tevatron Collider at Fermilab

    CERN Document Server

    Krieger, B; Bacchetta, N; Centro, Sandro; Christofek, L; García-Sciveres, M; Haber, C; Hanagaki, K; Hoff, J; Johnson, M; Von der Lippe, H; Mandelli, E; Meng, G; Nomerotski, A; Pellet, D; Rapidis, P; Utes, M; Walder, J P; Weber, M; Wester, W; Wilkes, T; Yarema, R J; Yao, W; Zimmerman, T

    2004-01-01

    SVX4 is the new silicon strip readout IC designed to meet the increased radiation tolerance requirements for Run IIb at the Tevatron collider. Devices have been fabricated, tested, and approved for production. The SVX4 design is a technology migration of the SVX3D design currently in use by CDF. Whereas SVX3D was fabricated in a 0.8 mu m radiation-hard process, SVX4 was fabricated in a standard 0.25 mu m mixed-signal CMOS technology using the "radiation tolerant by design" transistor topologies devised by the RD-49 collaboration. The specific cell layouts include digital cells developed by the ATLAS Pixel group, and full-custom analog blocks. Unlike its predecessors, the new design also includes the necessary features required for generic use by both the CDF and DO experiments at Fermilab. Performance of the IC includes >20 Mrad total dose tolerance, and ~2000 e- rms equivalent input noise charge with 40 pF input capacitance, when sampled at 132 ns period with an 80 ns preamp risetime. At the nominal digitize...

  2. Optimising electron microscopy experiment through electron optics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Y. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France); Hitachi High-Technologies Corporation, 882, Ichige, Hitachinaka, Ibaraki 312-8504 (Japan); Gatel, C.; Snoeck, E. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France); Houdellier, F., E-mail: florent.houdellier@cemes.fr [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France)

    2017-04-15

    We developed a new type of electron trajectories simulation inside a complete model of a modern transmission electron microscope (TEM). Our model incorporates the precise and real design of each element constituting a TEM, i.e. the field emission (FE) cathode, the extraction optic and acceleration stages of a 300 kV cold field emission gun, the illumination lenses, the objective lens, the intermediate and projection lenses. Full trajectories can be computed using magnetically saturated or non-saturated round lenses, magnetic deflectors and even non-cylindrical symmetry elements like electrostatic biprism. This multi-scale model gathers nanometer size components (FE tip) with parts of meter length (illumination and projection systems). We demonstrate that non-trivial TEM experiments requiring specific and complex optical configurations can be simulated and optimized prior to any experiment using such model. We show that all the currents set in all optical elements of the simulated column can be implemented in the real column (I2TEM in CEMES) and used as starting alignment for the requested experiment. We argue that the combination of such complete electron trajectory simulations in the whole TEM column with automatic optimization of the microscope parameters for optimal experimental data (images, diffraction, spectra) allows drastically simplifying the implementation of complex experiments in TEM and will facilitate the development of advanced use of the electron microscope in the near future. - Highlights: • Using dedicated electron optics software, we calculate full electrons trajectories inside a modern transmission electron microscope. • We have determined how to deal with multi-scale electron optics elements like high voltage cold field emission source. • W • e have succeed to model both weak and strong magnetic lenses whether in saturated or unsaturated conditions as well as electrostatic biprism and magnetic deflectors. • We have applied this model

  3. Reconfigurable and responsive droplet-based compound micro-lenses

    Science.gov (United States)

    Nagelberg, Sara; Zarzar, Lauren D.; Nicolas, Natalie; Subramanian, Kaushikaram; Kalow, Julia A.; Sresht, Vishnu; Blankschtein, Daniel; Barbastathis, George; Kreysing, Moritz; Swager, Timothy M.; Kolle, Mathias

    2017-03-01

    Micro-scale optical components play a crucial role in imaging and display technology, biosensing, beam shaping, optical switching, wavefront-analysis, and device miniaturization. Herein, we demonstrate liquid compound micro-lenses with dynamically tunable focal lengths. We employ bi-phase emulsion droplets fabricated from immiscible hydrocarbon and fluorocarbon liquids to form responsive micro-lenses that can be reconfigured to focus or scatter light, form real or virtual images, and display variable focal lengths. Experimental demonstrations of dynamic refractive control are complemented by theoretical analysis and wave-optical modelling. Additionally, we provide evidence of the micro-lenses' functionality for two potential applications--integral micro-scale imaging devices and light field display technology--thereby demonstrating both the fundamental characteristics and the promising opportunities for fluid-based dynamic refractive micro-scale compound lenses.

  4. [Therapeutic contact lenses and the advantages of high Dk materials].

    Science.gov (United States)

    Coral-Ghanem, Cleusa; Ghanem, Vinícius Coral; Ghanem, Ramon Coral

    2008-01-01

    Therapeutic contact lenses are useful in a variety of ocular surface diseases. Their main indications are: to relieve the pain; protect ocular surface; promote corneal healing and epithelial regeneration; seal a leaking corneal wound and deliver ophthalmic drugs on the ocular surface. There are several kinds of lens designs and materials, and their choice is dependent on the specific disease to be treated, the duration of treatment and the physiologic needs of the diseased cornea. Bullous keratopathy, recurrent epithelial erosion syndrome, dry eye and postoperative epithelial defects are amongst their indications. Therapeutic contact lenses should not be indicated in the presence of active infectious keratitis or when the patient is not compliant. Corneal neovascularization, giant papillary conjunctivitis and infectious keratitis are serious complications, which can be prevented by correctly fitting and maintaining the therapeutic contact lenses. Silicon-hydrogel therapeutic contact lenses, due to their higher oxygen permeability, allow extended wear schedules, decreasing the need for frequent lens replacement.

  5. Lensing of 21-cm fluctuations by primordial gravitational waves.

    Science.gov (United States)

    Book, Laura; Kamionkowski, Marc; Schmidt, Fabian

    2012-05-25

    Weak-gravitational-lensing distortions to the intensity pattern of 21-cm radiation from the dark ages can be decomposed geometrically into curl and curl-free components. Lensing by primordial gravitational waves induces a curl component, while the contribution from lensing by density fluctuations is strongly suppressed. Angular fluctuations in the 21-cm background extend to very small angular scales, and measurements at different frequencies probe different shells in redshift space. There is thus a huge trove of information with which to reconstruct the curl component of the lensing field, allowing tensor-to-scalar ratios conceivably as small as r~10(-9)-far smaller than those currently accessible-to be probed.

  6. Contact lenses and acute exposure to ultraviolet radiation.

    Science.gov (United States)

    Cullen, A P; Dumbleton, K A; Chou, B R

    1989-06-01

    The eyes of twenty-three pigmented rabbits (weight approximately 2kg) were irradiated with a single dose of UVB (285 to 315 nm total bandpass at approximately 450 muW.cm-2 irradiance) for exposure times of 22s to 1680s. One group wore UV-transmitting soft contact lenses during exposure of one eye with the fellow eye serving as a control while another group wore a UV-absorbing lens on each eye with only one eye irradiated. UV-transmitting contact lenses did not affect the clinical response to UV exposure whereas the UV-absorbing contact lenses protected the corneas as could have been predicted by consideration of the absorption characteristics of the lenses at the experimental waveband. In no case was there any evidence of adhesion between the contact lens and the corneal epithelium.

  7. Fitting gas-permeable contact lenses after penetrating keratoplasty.

    Science.gov (United States)

    Genvert, G I; Cohen, E J; Arentsen, J J; Laibson, P R

    1985-05-15

    Between Sept. 1, 1981, and Jan. 31, 1984, 74 eyes (70 patients) were fitted with gas-permeable Polycon contact lenses and monitored for at least six months (range, six to 33 months; mean, 14 months). The major indications for hard contact lens fitting were astigmatism and anisometropia. Astigmatism in this series ranged from 0 to 17.50 diopters (mean, 7.7 diopters). Most patients achieved visual acuities of 20/40 or better (67 of 74, 90%) with contact lenses. Contact lenses were discontinued in 18% (13 of 74), because of graft rejection in four cases and because of contact lens intolerance in nine cases. Our results demonstrated that gas-permeable hard lenses can be fitted successfully in most patients unable to achieve optimal vision with spectacle correction after penetrating keratoplasty.

  8. [Unusual complications after wearing hard and soft contact lenses].

    Science.gov (United States)

    Roth, H W; Teuchert, J

    1990-01-01

    In a clinical long-term study over a period of 10 years with 3850 patients wearing hard and soft contact lenses, unusual reactions of the cornea and perilimbal conjunctiva have been observed in 3% of all cases. Mainly corneal abrasions, cracks, clouds and mosaics have been observed, which were analyzed as being rare contact lens complications. The causes were lack of proper maintenance of the contact lenses, such as mistakes in cleaning and disinfecting the lenses, mishandling or toxic and allergic reactions due to cleaning and disinfection solutions. Only exact ophthalmological monitoring of the anterior parts of the eye and laboratory tests on the worn lenses permit differentiation between primary eye diseases and contact lens-induced complications.

  9. The Danger of Using Tap Water with Contact Lenses

    Science.gov (United States)

    Acanthamoeba is a microbe that is very common in tap water. It has two forms: the trophozoite and the cyst. These trophozoites and cysts can stick to the surface of your contact lenses and then infect your eye.

  10. Development of Compact Lenses for Micro Four-Thirds System

    Science.gov (United States)

    Koiwai, Tamotsu; Akita, Hidenori

    In 2010, "The micro SLR Olympus PEN" of Micro Four Thirds standard won double titles of CAMERA GRAND PRIX .The characteristics of Olympus PEN series are high-quality, compact, lightweight, no feeling of burden/stress and easy to take both still images and movies by SLR quality. Especially, the consciousness of compact and lightweight is taken into the series’ entire system including the body and interchangeable lenses. We have developed the interchangeable lenses by aiming ultimate miniaturization for optical and lens-barrel design along with making the miniaturizing compliance of Micro Four Thirds standard useful. In order to create compact and lightweight interchangeable lenses, a number of technical difficulties, such as realization of thinner design by adapting lens-barrel retraction system, lens-barrel with a high degree of accuracy, quick and silent AF, adaptation of special lenses, thorough trimming of weight, had to be overcome in the developmental process. Here we refer to these miniaturization technologies.

  11. Gravitational lensing of the CMB: A Feynman diagram approach

    Directory of Open Access Journals (Sweden)

    Elizabeth E. Jenkins

    2014-09-01

    Full Text Available We develop a Feynman diagram approach to calculating correlations of the Cosmic Microwave Background (CMB in the presence of distortions. As one application, we focus on CMB distortions due to gravitational lensing by Large Scale Structure (LSS. We study the Hu–Okamoto quadratic estimator for extracting lensing from the CMB and derive the noise of the estimator up to O(ϕ4 in the lensing potential ϕ. By identifying the diagrams responsible for the previously noted large O(ϕ4 term, we conclude that the lensing expansion does not break down. The convergence can be significantly improved by a reorganization of the ϕ expansion. Our approach makes it simple to obtain expressions for quadratic estimators based on any CMB channel, including many previously unexplored cases. We briefly discuss other applications to cosmology of this diagrammatic approach, such as distortions of the CMB due to patchy reionization, or due to Faraday rotation from primordial axion fields.

  12. [Laboratory study of the cytotoxicity of colored soft contact lenses].

    Science.gov (United States)

    Almesmary, A A

    1999-01-01

    In the clinical practice we have met with the fact that some patients did not tolerate soft coloured contact lenses even when they used them for a short time. To find whether the cause is the composition of these lenses, mainly the adding of stain, he used the laboratory test to determine cytotoxicity, the test of dynamic observation of cytotoxicity where the cells cultured in vitro are the experimental object. On the basis of the results of this test commonly used for the determination of the cytotoxicity of implantation materials, he thinks that the cause of intolerance of coloured lenses is not their toxicity but other phenomena. An individual hypersensitivity or insufficient care of lenses (the influence of disinfectants) can be among these causes.

  13. Primary aberration coefficients for axial gradient-index lenses

    Science.gov (United States)

    Bociort, Florian

    1999-08-01

    As for homogeneous lenses, for axial gradients the analysis of the Seidel and chromatic aberration coefficients can be very useful in lens design. However, at present few commercial optical design programs list the Seidel aberrations of GRIN lenses and none of them lists the chromatic aberrations. In order to facilitate the computer implementation of the chromatic aberrations of axial GRIN lenses a new mathematical derivation for the axial and lateral color coefficients is presented. Also, new qualitative insight into the properties of axial GRIN lenses is obtained by introducing the thin-lens approximation in the aberration expressions. Within the domain of validity of this approximation, the primary aberrations of an axial GRIN lens are equivalent to those of a pair of homogeneous aspherical lens in contact, having a common plane surface and having refractive indices and Abbe numbers equal to the corresponding axial GRIN values at the two end surfaces.

  14. Phosphorylcholine impairs susceptibility to biofilm formation of hydrogel contact lenses.

    Science.gov (United States)

    Selan, Laura; Palma, Stefano; Scoarughi, Gian Luca; Papa, Rosanna; Veeh, Richard; Di Clemente, Daniele; Artini, Marco

    2009-01-01

    To compare silicone-hydrogel, poly(2-hydroxyethyl methacrylate) (pHEMA), and phosphorylcholine-coated (PC-C) contact lenses in terms of their susceptibility to biofilm formation by Staphylococcus epidermidis and Pseudomonas aeruginosa. Laboratory investigation. Biofilm formation on colonized test lenses was evaluated with confocal microscopy and in vitro antibiotic susceptibility assays. The results of the latter assays were compared with those performed on planktonic cultures of the same organism. For both microorganisms, sessile colonies on silicone-hydrogel and pHEMA lenses displayed lower antibiotic susceptibility than their planktonic counterparts. In contrast, the susceptibility of cultures growing on PC-C lenses was comparable with that for planktonic cultures. In particular, minimum inhibitory concentration for Tazocin (piperacillin plus tazobactam; Wyeth Pharmaceuticals, Aprilia, Italy; S. epidermidis) and gentamicin (P. aeruginosa) was identical, either in the presence of PC-C support or in planktonic cultures (Tazocin, lenses (0.4 mug/ml) with respect to planktonic cultures (0.2 mug/ml). Confocal microscopy of lenses colonized for 24 hours with P. aeruginosa green fluorescent protein-expressing cells revealed a sessile colonization on silicone-hydrogel lens and a few isolated bacterial cells scattered widely over the surface of the PC-C lens. An increase in antibiotic susceptibility of bacterial cultures was associated with diminished bacterial adhesion. Our results indicate that PC-C lenses seem to be more resistant than silicone-hydrogel and pHEMA lenses to bacterial adhesion and colonization. This feature may facilitate their disinfection.

  15. What is Gravitational Lensing? (LBNL Summer Lecture Series)

    Energy Technology Data Exchange (ETDEWEB)

    Leauthaud, Alexie; Nakajima, Reiko [Berkeley Center for Cosmological Physics

    2009-07-28

    Summer Lecture Series 2009: Gravitational lensing is explained by Einstein's general theory of relativity: galaxies and clusters of galaxies, which are very massive objects, act on spacetime by causing it to become curved. Alexie Leauthaud and Reiko Nakajima, astrophysicists with the Berkeley Center for Cosmological Physics, will discuss how scientists use gravitational lensing to investigate the nature of dark energy and dark matter in the universe.

  16. Periodic self-lensing from accreting massive black hole binaries

    Science.gov (United States)

    D'Orazio, Daniel J.; Di Stefano, Rosanne

    2018-03-01

    Nearly 150 massive black hole binary (MBHB) candidates at sub-pc orbital separations have been reported in recent literature. Nevertheless, the definitive detection of even a single such object remains elusive. If at least one of the black holes is accreting, the light emitted from its accretion disc will be lensed by the other black hole for binary orbital inclinations near to the line of sight. This binary self-lensing could provide a unique signature of compact MBHB systems. We show that, for MBHBs with masses in the range 106-1010 M⊙ and with orbital periods less than ˜10 yr, strong lensing events should occur in one to 10s of per cent of MBHB systems that are monitored for an entire orbit. Lensing events will last from days for the less massive, shorter period MBHBs to a year for the most massive ˜10 year orbital period MBHBs. At small inclinations of the binary orbit to the line of sight, lensing must occur and will be accompanied by periodicity due to the relativistic Doppler boost. Flares at the same phase as the otherwise average flux of the Doppler modulation would be a smoking gun signature of self-lensing and can be used to constrain binary parameters. For MBHBs with separation ≳100 Schwarzschild radii, we show that finite-sized source effects could serve as a probe of MBH accretion disc structure. Finally, we stress that our lensing probability estimate implies that ˜10 of the known MBHB candidates identified through quasar periodicity should exhibit strong lensing flares.

  17. Laue diffraction lenses for astrophysics: From theory to experiments

    OpenAIRE

    Halloin, H.

    2006-01-01

    Based on the laws of X-ray diffraction in crystals, Laue lenses offer a promising way to achieve the sensitivity and angular resolution leap required for the next generation of hard X-ray and gamma-ray telescopes. The present paper describes the instrumental responses of Laue diffraction lenses designed for nuclear astrophysics. Different possible geometries are discussed, as well as the corresponding spectral and imaging capabilities. These theoretical predictions are then compared with Mont...

  18. In Vitro Compatibility of Contact Lenses With Corneal Epithelial Cells.

    Science.gov (United States)

    Vijay, Ajay K; Fadli, Zohra; Lakkis, Carol; Coles-Brennan, Chantal; Willcox, Mark D P

    2017-07-18

    To determine the interaction of contact lenses of different materials with corneal epithelial cells grown in tissue culture. Two different corneal epithelial cell lines were grown to confluence in culture media. Two hydrogel contact lenses with and without polyvinylpyrrolidone (PVP) {1-DAY ACUVUE MOIST (1-Day ACUVUE [hydrogel lenses]) and a silicone hydrogel contact lens, AIR OPTIX NIGHT & DAY} were removed from their blister packs, washed in phosphate-buffered saline, and applied to the cells. After exposure for 24 hr at 37°C, lenses were removed, and the corneal cells and supernatants processed. Supernatants from the cell assays were used to quantify the amount of 17 different cytokines that were produced using a multiplex bead assay. Cells were stained to assess amount of cell death (apoptosis or necrosis) or stained to determine the level of mitochondrial activity. Stimulants of necrotic death (latex) or apoptotic death (sorbitol) were used as positive controls. Cells produced cytokines during normal growth. Exposure of cells to the hydrogel lenses resulted in only minimal changes to normal production of cytokines, but latex or sorbitol produced the most change. Exposure of the cells to all three lenses caused 4% to 23% reduction in mitochondrial activity, whereas exposure to the positive controls caused 71% to 98% reduction in mitochondrial activity. Exposure of the corneal epithelial cells to contact lenses produced minimal morphological changes, whereas exposure to latex or sorbitol produced significant changes to the human corneal epithelial cell line. Exposure of corneal epithelial cells to contact lenses had minimal impact on their physiology. There was no difference in epithelial cell responses to hydrogel with or without PVP compared with the silicone hydrogel contact lens.

  19. Direct probe of dark energy through gravitational lensing effect

    Science.gov (United States)

    He, Hong-Jian; Zhang, Zhen

    2017-08-01

    We show that gravitational lensing can provide a direct method to probe the nature of dark energy at astrophysical scales. For lensing system as an isolated astrophysical object, we derive the dark energy contribution to gravitational potential as a repulsive power-law term, containing a generic equation of state parameter w. We find that it generates w-dependent and position-dependent modification to the conventional light orbital equation of w=-1. With post-Newtonian approximation, we compute its direct effect for an isolated lensing system at astrophysical scales and find that the dark energy force can deflect the path of incident light rays. We demonstrate that the dark-energy-induced deflection angle ΔαDEpropto M(1+1/3w) (with 1+1/3w > 0), which increases with the lensing mass M and consistently approaches zero in the limit M→ 0. This effect is distinctive because dark energy tends to diffuse the rays and generates concave lensing effect. This is in contrast to the conventional convex lensing effect caused by both visible and dark matter. Measuring such concave lensing effect can directly probe the existence and nature of dark energy. We estimate this effect and show that the current gravitational lensing experiments are sensitive to the direct probe of dark energy at astrophysical scales. For the special case w=-1, our independent study favors the previous works that the cosmological constant can affect light bending, but our prediction qualitatively and quantitatively differ from the literature, including our consistent realization of ΔαDE → 0 (under 0M→ ) at the leading order.

  20. [The correction of anisomyopia with contact lenses (author's transl)].

    Science.gov (United States)

    Dreifus, M; Tschopp, H; Bosshard, C

    1976-01-01

    Currently it is believed that correction of anisomyopia with contact lenses is contraindicated because most anisomyopias are axial. By determination of dioptric aniseiconia it has been shown that this is smaller than generally believed also with the correction by contact lenses. In childhood it is advisable to correct an anisomyopia fully as early as possible because the distortion of room perception by spectacles seems to play a much bigger role in higher anisomyopia than the functional aniseiconia. The results are shown in tables.