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

Description: The Large Hadron Collider (LHC) at CERN promises a major step forward in the understanding of the fundamental nature of matter. The ATLAS experiment is a general-purpose detector for the LHC, whose design was guided by the need to accommodate the wide spectrum of possible physics signatures. The major remit of the ATLAS experiment is the exploration of the TeV mass scale where groundbreaking discoveries are expected. In the focus are the investigation of the electroweak symmetry breaking and linked to this the search for the Higgs boson as well as the search for Physics beyond the Standard Model. In this report a detailed examination of the expected performance of the ATLAS detector is provided, with a major aim being to investigate the experimental sensitivity to a wide range of measurements and potential observations of new physical processes. An earlier summary of the expected capabilities of ATLAS was compiled in 1999 [1]. A survey of physics capabilities of the CMS detector was published in [2]. The design of the ATLAS detector has now been finalised, and its construction and installation have been completed [3]. An extensive test-beam programme was undertaken. Furthermore, the simulation and reconstruction software code and frameworks have been completely rewritten. Revisions incorporated reflect improved detector modelling as well as major technical changes to the software technology. Greatly improved understanding of calibration and alignment techniques, and their practical impact on performance, is now in place. The studies reported here are based on full simulations of the ATLAS detector response. A variety of event generators were employed. The simulation and reconstruction of these large event samples thus provided an important operational test of the new ATLAS software system. In addition, the processing was distributed world-wide over the ATLAS Grid facilities and hence provided an important test of the ATLAS ...
Date: November 28, 2011
Creator: Aad, G.; Abat, E.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A. et al.
Partner: UNT Libraries Government Documents Department

Discovery of TeV Gamma-Ray Emission from the Cygnus Region

Description: The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at {approx}12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray production and propagation. This observation indicates the existence of either hard-spectrum cosmic-ray sources and/or other sources of TeV gamma rays in the region.
Date: November 28, 2006
Creator: Abdo, A.A.; Allen, B.; Berley, D.; Blaufuss, E.; Casanova, S.; Chen, C. et al.
Partner: UNT Libraries Government Documents Department

Commissioning the LCLS Injector

Description: The Linac Coherent Light Source (LCLS) is a SASE x-ray Free-Electron Laser (FEL) project presently under construction at SLAC. The injector section, from drive laser and RF photocathode gun through first bunch compressor chicane, was installed in fall 2006. Initial system commissioning with an electron beam was completed in August 2007, with the goal of a 1.2-micron emittance in a 1-nC bunch clearly demonstrated. The second phase of commissioning, including second bunch compressor and full linac, is planned for 2008, with FEL commissioning in 2009. We report experimental results and experience gained in the first phase of commissioning, including the photo-cathode drive laser, RF gun, photocathode, S-band and X-band RF systems, first bunch compressor, and the various beam diagnostics.
Date: November 28, 2007
Creator: Akre, R.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G. et al.
Partner: UNT Libraries Government Documents Department

Renewable Energy for Microenterprise

Description: This guide provides readers with a broad understanding of the potential benefits that current renewable energy technologies can offer rural microenterprises. It also introduces the institutional approaches that have been developed to make RE technologies accessible to microentrepreneurs and the challenges that these entrepreneurs have encountered.
Date: November 28, 2000
Creator: Allderdice, A. & Rogers, J.H.
Partner: UNT Libraries Government Documents Department

Design and Factory Test of the E /E- Frascati Linear Accelerator for DAFNE

Description: The electron-positron accelerator for the DAFNE project has been built and is in test at Titan Beta in Dublin, CA. This S-Band RF linac system utilizes four 45 MW sledded klystrons and 16-3 m accelerating structures to achieve the required performance. It delivers a 4 ampere electron beam to the positron converter and accelerates the resulting positrons to 550 MeV. The converter design uses a 4.3T pulsed tapered flux compressor along with a pseudo-adiabatic tapered field to a 5 KG solenoid over the first two positron accelerating sections. Quadrupole focusing is used after 100 MeV. The system performance is given in Table 1. This paper briefly describes the design and development of the various subassemblies in this system and gives the initial factory test data.
Date: November 28, 2011
Creator: Anamkath, H.; Lyons, S.; Nett, D.; Treas, P.; Whitham, K.; Zante, T. et al.
Partner: UNT Libraries Government Documents Department

Magnetocentrifugal Winds in 3D: Nonaxisymmetric Steady State

Description: Outflows can be loaded and accelerated to high speeds along rapidly rotating, open magnetic field lines by centrifugal forces. Whether such magnetocentrifugally driven winds are stable is a longstanding theoretical problem. As a step towards addressing this problem, we perform the first large-scale 3D MHD simulations that extend to a distance {approx} 10{sup 2} times beyond the launching region, starting from steady 2D (axisymmetric) solutions. In an attempt to drive the wind unstable, we increase the mass loading on one half of the launching surface by a factor of {radical}10, and reduce it by the same factor on the other half. The evolution of the perturbed wind is followed numerically. We find no evidence for any rapidly growing instability that could disrupt the wind during the launching and initial phase of propagation, even when the magnetic field of the magnetocentrifugal wind is toroidally dominated all the way to the launching surface. The strongly perturbed wind settles into a new steady state, with a highly asymmetric mass distribution. The distribution of magnetic field strength is, in contrast, much more symmetric. We discuss possible reasons for the apparent stability, including stabilization by an axial poloidal magnetic field, which is required to bend field lines away from the vertical direction and produce a magnetocentrifugal wind in the first place.
Date: November 28, 2006
Creator: Anderson, Jeffrey M.; Li, Zhi-Yun; /Virginia U., Astron. Dept.; Krasnopolsky, Ruben; /Toronto U., Astron. Dept.; Blandford, Roger D. et al.
Partner: UNT Libraries Government Documents Department

Design and Fabrication of a Single-Aperture 11T Nb3Sn Dipole Model for LHC Upgrades

Description: The planned upgrade of the LHC collimation system includes additional collimators to be installed in the dispersion suppressor areas of points 2, 3 and 7. To provide the necessary longitudinal space for the collimators, a replacement of 8.33 T Nb-Ti LHC main dipoles with 11 T dipoles based on Nb{sub 3}Sn superconductor compatible with the LHC lattice and main systems is being considered. To demonstrate this possibility FNAL and CERN have started a joint program to develop a 2 m long single-aperture dipole magnet with the nominal field of 11 T at {approx}11.85 kA current and 60 mm bore. This paper describes the demonstrator magnet magnetic and mechanical designs and analysis, coil fabrication procedure. The Nb{sub 3}Sn strand and cable parameters and test results are also reported.
Date: November 28, 2011
Creator: Andreev, N.; Apollinari, G.; Barzi, E.; Bossert, R.; Nobrega, F.; Novitski, I. et al.
Partner: UNT Libraries Government Documents Department

Measurment of B Decays to phi K gamma

Description: The authors search for the decays B{sup -} {yields} {phi}K{sup -}{gamma} and {bar B}{sup 0} {yields} {phi}{bar K}{sup 0}{gamma} in a data sample of 228 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector. They measure the branching fraction {Beta}(B{sup -} {yields} {phi}K{sup -}{gamma}) = (3.5 {+-} 0.6 {+-} 0.4) x 10{sup -6} and set an upper limit {Beta}({bar B}{sup 0} {yields} {phi}{bar K}{sup 0}{gamma}) < 2.7 x 10{sup -6} at the 90% confidence level. They also measure the direct CP asymmetry in B{sup -} {yields} {phi}K{sup -}{gamma}, {Alpha}{sub CP} = (-26 {+-} 14 {+-} 5)%. The uncertainties are statistical and systematic, respectively.
Date: November 28, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Search for the Baryon and Lepton Number Violating Decays tau to Lambda h

Description: The authors have searched for the violation of baryon number B and lepton number L in the (B-L)-conserving modes {tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -} as well as the (B-L)-violating modes {tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {Lambda}{sup 0}K{sup -} using 237 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They do not observe any signal and determine preliminary upper limits on the branching fractions {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -}) < 5.9 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -}) < 5.8 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -}) < 7.2 x 10{sup -8}, and {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}K{sup -}) < 15 x 10{sup -8} at 90% confidence level.
Date: November 28, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Software for reflectivity calculations of x-ray mirrors. Revision 1

Description: With VAX software and the data libraries of Henke and Biggs-Lighthill, we have created a library of atomic scattering factors f/sub 1/ and f/sub 2/ in the energy range 0.1 keV to 10.0 keV. Scattering factor values for the elements Z = 1 to Z = 94 and in the above energy range are stored in a keyed access library (key = element symbol). This library allows one to calculate reflectivity rapidly and fold it with other components in an x-ray detector channel. Additional software allows the library data to be easily extended to higher energies. Applications have so far included KB x-ray microscopes and low energy spectrometers with mirror channels.
Date: November 28, 1984
Creator: Auerbach, J.M. & Tirsell, K.G.
Partner: UNT Libraries Government Documents Department

Tritium emissions from 200 East Area Double-Shell Tanks

Description: This document evaluates the need for tritium sampling of the emissions from the 200 East Area Double Shell Tanks based on the requirements of {open_quotes}National Emission Standards for Hazardous Air Pollutants{close_quotes} (NESHAP). The NESHAP requirements are specified in 40 Code of Federal Regulation (CFR), Part 61, Subpart H; {open_quotes}National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities{close_quotes}.
Date: November 28, 1994
Creator: Bachand, D. D.
Partner: UNT Libraries Government Documents Department

Groundwater Monitoring Plan for the Hanford Site 216-B-3 Pond RCRA Facility

Description: The 216-B-3 Pond was a series of ponds for disposal of liquid effluent from past Hanford production facilities. In 1990, groundwater monitoring at B Pond was elevated from "detection" to assessment status because total organic halides and total organic carbon were found to exceed critical means in two wells. Groundwater quality assessment, which ended in 1996, failed to find any specific hazardous waste contaminant that could have accounted for the isolated occurrences of elevated total organic halides and total organic carbon. Hence, the facility was subsequently returned to detection-level monitoring in 1998. Exhaustive groundwater analyses during the assessment period indicated that only two contaminants, tritium and nitrate, could be positively attributed to the B Pond System, with two others (arsenic and I-129) possibly originating from B Pond. Chemical and radiological analyses of soil at the main pond and 216-B-3-3 ditch has not revealed significant contamination. Based on the observed, minor contamination in groundwater and in the soil column, three parameters were selected for site-specific, semiannual monitoring; gross alpha, gross beta, and specific conductance. Total organic halides and total organic carbon are included as constituents because of regulatory requirements. Nitrate, tritium, arsenic, and iodine-129 will be monitored under the aegis of Hanford site-wide monitoring. Although the B Pond System is not scheduled to advance from RCRA interim status to final status until the year 2003, a contingency plan for an improved monitoring strategy, which will partially emulate final status requirements, will be contemplated before the official change to final status. This modification will allow a more sensible and effective screening of groundwater for the facility.
Date: November 28, 2000
Creator: Barnett, D. Brent; Smith, Ronald M. & Chou, Charissa J.
Partner: UNT Libraries Government Documents Department

NON-DESTRUCTIVE ANALYSIS OF URANIUM IN GRAPHITE FUEL ELEMENTS BY NEUTRON ACTIVATION

Description: A method is presented for the determination of uranium (as U/sup 238/) in uraniuni-loaded graphite fuel elenients by a non-destructive, direct radioactivity analysis technique. A 200-cbannel pulse-height analyzer, equipped with a 3 in. x 3 in. NaI(Tl) crystal, is used to measure the Np/sup 239/ radioactivity of the neutron-irradiated samples. The amount of U/sup 238/ in the test samples is deterimined quantitatively by comparing the Np/sup 239/ radioactivity induced in each sample with the Np/sup 239/ radioactivity induced into known standards of U/sup 238/ processed under the same conditions as the test samples. The limit of detection for U/sup 238/in samples of normal uranium composition for this method is about 1.0 x l0-4 ug. (auth)
Date: November 28, 1961
Creator: Bate, L.C.; Hampton, W.J. & Leddicotte, G.W.
Partner: UNT Libraries Government Documents Department

Farm and Food Support Under USDA's Section 32 Program

Description: This report discusses “Section 32”, which is a permanent appropriation that since 1935 has earmarked the equivalent of 30% of annual customs receipts to support the farm sector through a variety of activities. Today, most of this appropriation (now approximately $6.5 billion yearly) is transferred to the U.S. Department of Agriculture (USDA) account that funds child nutrition programs.
Date: November 28, 2006
Creator: Becker, Geoffrey S.
Partner: UNT Libraries Government Documents Department

Free-Spinning-Tunnel Tests of a 1/24-Scale Model of the McDonnell XP-88 Airplane with a Vee Tail

Description: "An investigation of the spin and recovery characteristics of a 1/24-scale model of the McDonnell XP-88 airplane has been conducted in the Langley 20-ft free-spinning tunnel. Results of tests with a conventional tail have been previously reported; the results presented herein are for the model with a vee tail installed. The effects of control settings and movements on the erect and inverted spin and recovery characteristics of the model. In the normal loading were determined" (p. 1).
Date: November 28, 1947
Creator: Berman, Theodore
Partner: UNT Libraries Government Documents Department

SciDAC Visualization and Analytics Center for EnablingTechnology

Description: The SciDAC2 Visualization and Analytics Center for EnablingTechnologies (VACET) began operation on 10/1/2006. This document, dated11/27/2006, is the first version of the VACET project management plan. Itwas requested by and delivered to ASCR/DOE. It outlines the Center'saccomplishments in the first six weeks of operation along with broadobjectives for the upcoming future (12-24 months).
Date: November 28, 2006
Creator: Bethel, E. Wes; Johnson, Chris; Joy, Ken; Ahern, Sean; Pascucci,Valerio; Childs, Hank et al.
Partner: UNT Libraries Government Documents Department