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Challenges And Concepts for Design of An Interaction Region With Push-Pull Arrangement of Detectors - An Interface Document
Two experimental detectors working in a push-pull mode has been considered for the Interaction Region of the International Linear Collider. The push-pull mode of operation sets specific requirements and challenges for many systems of detector and machine, in particular for the IR magnets, for the cryogenics and alignment system, for beamline shielding, for detector design and overall integration, and so on. These challenges and the identified conceptual solutions discussed in the paper intend to form a draft of the Interface Document which will be developed further in the nearest future. The authors of the present paper include the organizers and conveners of working groups of the workshop on engineering design of interaction region IRENG07, the leaders of the IR Integration within Global Design Effort Beam Delivery System, and the representatives from each detector concept submitting the Letters Of Intent.
Date:
October 14, 2011
Creator:
Parker, B.; /Brookhaven; Herve, Alain; Osborne, J.; /CERN; Mikhailichenko, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Theoretical study of transverse-longitudinal emittance coupling
The effect of a weakly coupled periodic lattice in terms of achieving emittance exchange between the transverse and longitudinal directions is investigated using the generalized Courant-Snyder theory for coupled lattices. Recently, the concept and technique of transverse-longitudinal emittance coupling have been proposed for applications in the Linac Coherent Light Source and other free-electron lasers to reduce the transverse emittance of the electron beam. Such techniques can also be applied to the driver beams for the heavy ion fusion and beam-driven high energy density physics, where the transverse emittance budget is typically tighter than the longitudinal emittance. The proposed methods consist of one or several coupling components which completely swap the emittances of one of the transverse directions and the longitudinal direction at the exit of the coupling components. The complete emittance exchange is realized in one pass through the coupling components. In the present study, we investigate the effect of a weakly coupled periodic lattice in terms of achieving emittance exchange between the transverse and longitudinal directions. A weak coupling component is introduced at every focusing lattice, and we would like to determine if such a lattice can realize the function of emittance exchange.
Date:
April 14, 2011
Creator:
Qin, H.; Davidson, R. C.; Chung, M.; Barnard, J. J. & Wang, T. F.
Object Type:
Article
System:
The UNT Digital Library
Wide-Field Astronomical Surveys in the Next Decade
Wide-angle surveys have been an engine for new discoveries throughout the modern history of astronomy, and have been among the most highly cited and scientifically productive observing facilities in recent years. This trend is likely to continue over the next decade, as many of the most important questions in astrophysics are best tackled with massive surveys, often in synergy with each other and in tandem with the more traditional observatories. We argue that these surveys are most productive and have the greatest impact when the data from the surveys are made public in a timely manner. The rise of the 'survey astronomer' is a substantial change in the demographics of our field; one of the most important challenges of the next decade is to find ways to recognize the intellectual contributions of those who work on the infrastructure of surveys (hardware, software, survey planning and operations, and databases/data distribution), and to make career paths to allow them to thrive.
Date:
November 14, 2011
Creator:
Strauss, Michael A.; Tyson, J. Anthony; Anderson, Scott F.; Axelrod, T. S.; Becker, Andrew C.; Bickerton, Steven J. et al.
Object Type:
Article
System:
The UNT Digital Library
Efficient scalable algorithms for hierarchically semiseparable matrices
Hierarchically semiseparable (HSS) matrix algorithms are emerging techniques in constructing the superfast direct solvers for both dense and sparse linear systems. Here, we develope a set of novel parallel algorithms for the key HSS operations that are used for solving large linear systems. These include the parallel rank-revealing QR factorization, the HSS constructions with hierarchical compression, the ULV HSS factorization, and the HSS solutions. The HSS tree based parallelism is fully exploited at the coarse level. The BLACS and ScaLAPACK libraries are used to facilitate the parallel dense kernel operations at the #12;ne-grained level. We have appplied our new parallel HSS-embedded multifrontal solver to the anisotropic Helmholtz equations for seismic imaging, and were able to solve a linear system with 6.4 billion unknowns using 4096 processors, in about 20 minutes. The classical multifrontal solver simply failed due to high demand of memory. To our knowledge, this is the #12;first successful demonstration of employing the HSS algorithms in solving the truly large-scale real-world problems. Our parallel strategies can be easily adapted to the parallelization of the other rank structured methods.
Date:
September 14, 2011
Creator:
Wang, Shen; Xia, Jianlin; Situ, Yingchong & Hoop, Maarten V. de
Object Type:
Article
System:
The UNT Digital Library
2011 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report
This report documents the status of revegetation projects and natural resources mitigation efforts conducted for remediated waste sites and other activities associated with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 cleanup of National Priorities List waste sites at Hanford. This report contains the vegetation monitoring data that was collected in the spring and summer of 2011 from the River Corridor Closure Contractor’s revegetation and mitigation areas on the Hanford Site.
Date:
November 14, 2011
Creator:
West, W. J.; Lucas, J. G. & Gano, K. A.
Object Type:
Report
System:
The UNT Digital Library
Low-Energy Run of Fermilab Electron Cooler's Beam Generation System
In the context of the evaluation of possibly using the Fermilab Electron Cooler for the proposed low-energy RHIC run at BNL, operating the cooler at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main conclusion of this feasibility study is that the cooler's beam generation system is suitable for BNL needs. The beam recirculation was stable for all tested parameters. In particular, a beam current of 0.38 A was achieved with the cathode magnetic field up to the maximum value presently available of 250 G. The energy ripple was measured to be 40 eV. A striking difference with running the 4.3 MeV beam (nominal for operation at FNAL) is that no unprovoked beam recirculation interruptions were observed. Electron cooling proposed to increase the luminosity of the RHIC collider for heavy ion beam energies below 10 GeV/nucleon [1] needs a good quality, 0.9-5 MeV electron beam. Preliminary design studies indicate that the scheme of the Recycler's electron cooler at FNAL is suitable for low-energy RHIC cooling and most parts of the cooler can be re-used after the end of the Tevatron Run II. To analyze issues related to the generation of the electron beam in …
Date:
March 14, 2011
Creator:
Prost, L. R.; Shemyakin, A.; Fedotov, A. & Kewisch, J.
Object Type:
Article
System:
The UNT Digital Library
Update on Angles and Sides of the CKM Unitarity Triangle from BaBar
We report several recent updates from the BABAR Collaboration on the matrix elements |V{sub cb}|, |V{sub ub}|, and |V{sub td}| of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix, and the angles {beta} and {alpha} of the unitarity triangle. Most results presented here are using the full BABAR {Upsilon}(4S) data set.
Date:
November 14, 2011
Creator:
Cheng, Chih-hsiang & /Caltech
Object Type:
Article
System:
The UNT Digital Library
CRADA Final Report: Process development for hybrid solar cells
TCF funding of a CRADA between LBNL and RSLE leveraged RSLE's original $1M investment in LBNL research and led to development of a solar cell fabrication process that will bring the high efficiency, high voltage hybrid tandem solar cell closer to commercialization. RSLE has already built a pilot line at its Phoenix, Arizona site.
Date:
February 14, 2011
Creator:
Ager, Joel W.
Object Type:
Report
System:
The UNT Digital Library
Techniques Employed to Conduct Postshot Drilling at the former Nevada Test Site
Postshot drilling provided essential data on the results of the underground nuclear tests conducted at the Nevada Test Site (NTS), now identified as the Nevada National Security Site (NNSS). It was the means by which samples from the zone of interest were obtained for radiochemical analysis. This handbook describes how Lawrence Livermore National Laboratory (LLNL) conducted postshot drilling operations at the NTS, and it provides a general understanding of the process. Postshot drilling is a specialized application of rotary drilling. Accordingly, this handbook gives a brief description of rotary drilling in Section 2 to acquaint the reader with the general subject before proceeding to the specialized techniques used in postshot drilling. In Section 3, the handbook describes the typical postshot drilling situation at the former NTS and the drilling methods used. Section 4 describes the typical sequence of operations in postshot drilling at the former NTS. Detailed information on special equipment and techniques is given in a series of appendices (A through F) at the end of the handbook.
Date:
April 14, 2011
Creator:
Dekin, W D
Object Type:
Report
System:
The UNT Digital Library
Open String Wavefunctions in Warped Compactifications
None
Date:
November 14, 2011
Creator:
Marchesano, Fernando; McGuirk, Paul & Shiu, Gary
Object Type:
Article
System:
The UNT Digital Library
Nuclear recoil energy scale in liquid xenon with application to the direct detection of dark matter
We show for the first time that the quenching of electronic excitation from nuclear recoils in liquid xenon is well-described by Lindhard theory, if the nuclear recoil energy is reconstructed using the combined (scintillation and ionization) energy scale proposed by Shutt et al.. We argue for the adoption of this perspective in favor of the existing preference for reconstructing nuclear recoil energy solely from primary scintillation. We show that signal partitioning into scintillation and ionization is well-described by the Thomas-Imel box model. We discuss the implications for liquid xenon detectors aimed at the direct detection of dark matter.
Date:
February 14, 2011
Creator:
Sorensen, P & Dahl, C E
Object Type:
Article
System:
The UNT Digital Library
ARM Climate Research Facility Quarterly Value-Added Product Report January 1–March 30, 2011
The purpose of this report is to provide a concise status update for value-added products (VAP) implemented by the Atmospheric Radiation Measurement Climate Research Facility. The report is divided into the following sections: (1) new VAPs for which development has begun, (2) progress on existing VAPs, and (3) future VAPs that have been recently approved.
Date:
June 14, 2011
Creator:
Sivaraman, C
Object Type:
Report
System:
The UNT Digital Library
China Energy and Emissions Paths to 2030
After over two decades of staggering economic growth and soaring energy demand, China has started taking serious actions to reduce its economic energy and carbon intensity by setting short and medium-term intensity reduction targets, renewable generation targets and various supporting policies and programs. In better understanding how further policies and actions can be taken to shape China's future energy and emissions trajectory, it is important to first identify where the largest opportunities for efficiency gains and emission reduction lie from sectoral and end-use perspectives. Besides contextualizing China's progress towards reaching the highest possible efficiency levels through the adoption of the most advanced technologies from a bottom-up perspective, the actual economic costs and benefits of adopting efficiency measures are also assessed in this study. This study presents two modeling methodologies that evaluate both the technical and economic potential of raising China's efficiency levels to the technical maximum across sectors and the subsequent carbon and energy emission implications through 2030. The technical savings potential by efficiency measure and remaining gap for improvements are identified by comparing a reference scenario in which China continues the current pace of with a Max Tech scenario in which the highest technically feasible efficiencies and advanced technologies …
Date:
January 14, 2011
Creator:
Fridley, David; Zheng, Nina; Zhou, Nan; Ke, Jing; Hasanbeigi, Ali; Morrow, Bill et al.
Object Type:
Report
System:
The UNT Digital Library
Curved Mesh Correction And Adaptation Tool to Improve COMPASS Electromagnetic Analyses
SLAC performs large-scale simulations for the next-generation accelerator design using higher-order finite elements. This method requires using valid curved meshes and adaptive mesh refinement in complex 3D curved domains to achieve its fast rate of convergence. ITAPS has developed a procedure to address those mesh requirements to enable petascale electromagnetic accelerator simulations by SLAC. The results demonstrate that those correct valid curvilinear meshes can not only make the simulation more reliable but also improve computational efficiency up to 30%. This paper presents a procedure to track moving adaptive mesh refinement in curved domains. The procedure is capable of generating suitable curvilinear meshes to enable large-scale accelerator simulations. The procedure can generate valid curved meshes with substantially fewer elements to improve the computational efficiency and reliability of the COMPASS electromagnetic analyses. Future work will focus on the scalable parallelization of all steps for petascale simulations.
Date:
November 14, 2011
Creator:
Luo, X.; Shephard, M.; Lee, L. Q.; Ng, C. & Ge, L.
Object Type:
Article
System:
The UNT Digital Library
Approaching the Island of Inversion: 34P
Yrast states in 34P were investigated using the 18O(18O,pn) reaction at energies of 20, 24, 25, 30, and 44 MeV at Florida State University and at Lawrence Berkeley National Laboratory. The level scheme was expanded, ray angular distributions were measured, and lifetimes were inferred with the Doppler-shift attenuation method by detecting decay protons in coincidence with one or more rays. The results provide a clearer picture of the evolution of structure approaching the 'Island of Inversion', particularly how the 1 and 2 particle-hole (ph) states fall in energy with increasing neutro number approaching inversion. However, the agreement of the lowest few states with pure sd shell model predictions shows that the level scheme of 34P is not itself inverted. Rather, the accumulated evidence indicates that the 1-ph states start at 2.3 MeV. A good candidate for the lowest 2-ph state lies at 6236 keV, just below the neutron separation energy of 6291 keV. Shell model calculations made using a small modification of the WBP interaction reproduce the negative-parity, 1-ph states rather well.
Date:
June 14, 2011
Creator:
Bender, P. C.; Hoffman, C. R.; Wiedeking, M.; Allmond, J. M.; Bernstein, L. A.; Burke, J. T. et al.
Object Type:
Article
System:
The UNT Digital Library
Analysis and correction of vertical dispersion in RHIC
In the context of preserving the polarization of proton beams, the source of vertical dispersion in RHIC is analyzed. Contributions to dispersion from non-coupling sources and coupling sources are compared. Based on the analysis of sources for dispersion, the right actuator for correcting dispersion is determined and a corresponding algorithm is developed.
Date:
September 14, 2011
Creator:
Liu, C. & Minty, M.
Object Type:
Report
System:
The UNT Digital Library
2010 Dry and 2009 - 2010 Wet Season Branchiopod Survey Report, Site 300
Lawrence Livermore National Laboratory (LLNL) requested that Condor Country Consulting, Inc. (CCCI) perform wet season surveys and manage the dry season sampling for listed branchiopods in two ponded locations within the Site 300 Experimental Test Site. Site 300 is located in Alameda and San Joaquin Counties, located between the Cities of Livermore and Tracy. The two pool locations have been identified for possible amphibian enhancement activities in support of the Compensation Plan for impacts tied to the Building 850 soil clean-up project. The Building 850 project design resulted in formal consultation with the U.S. Fish and Wildlife Service (USFWS) as an amendment (File 81420-2009-F-0235) to the site-wide Biological Opinion (BO) (File 1-1-02-F-0062) in the spring of 2009 and requires mitigation for the California tiger salamander (AMCA, Ambystoma californiense) and California red-legged frog (CRLF, Rana draytonii) habitat loss. Both pools contain breeding AMCA, but do not produce metamorphs due to limited hydroperiod. The pool to the southeast (Pool BC-FS-2) is the preferred site for amphibian enhancement activities, and the wetland to northwest (Pool OA-FS-1) is the alternate location for enhancement. However, prior to enhancement, LLNL has been directed by USFWS (BO Conservation Measure 17 iii) to 'conduct USFWS protocol-level branchiopod surveys …
Date:
March 14, 2011
Creator:
Dexter, W.
Object Type:
Report
System:
The UNT Digital Library
T2Well/ECO2N Version 1.0: Multiphase and Non-Isothermal Model for Coupled Wellbore-Reservoir Flow of Carbon Dioxide and Variable Salinity Water
At its most basic level, the injection of CO{sub 2} into geologic CO{sub 2} storage sites involves a system comprising the wellbore and the target reservoir. The wellbore is the only conduit available to emplace CO{sub 2} into reservoirs for long-term storage. At the same time, wellbores in general have been identified as the most likely conduit for CO{sub 2} and brine leakage from geologic carbon sequestration (GCS) sites, especially those in sedimentary basins with historical hydrocarbon production. We have developed a coupled wellbore and reservoir model for simulating the dynamics of CO{sub 2} injection and leakage through wellbores. The model describes the following processes: (1) upward or downward wellbore flow of CO{sub 2} and variable salinity water with transition from supercritical to gaseous CO{sub 2} including Joule-Thomson cooling, (2) exsolution of CO{sub 2} from the aqueous phase as pressure drops, and (3) cross flow into or interaction with layers of surrounding rock (reservoirs). We use the Drift-Flux Model and related conservation equations for describing transient two-phase non-isothermal wellbore flow of CO{sub 2}-water mixtures under different flow regimes and interacting with surrounding rock. The mass and thermal energy balance equations are solved numerically by a finite difference scheme with wellbore …
Date:
February 14, 2011
Creator:
Pan, L.; Oldenburg, C.M.; Wu, Y.-S. & Pruess, K.
Object Type:
Report
System:
The UNT Digital Library
Compact, Low-power and Precision Timing Photodetector Readout
Photodetector readout for next generation high event rate particle identification and single-photon detection requires a digitizer capable of integrated recording of dense arrays of sensor elements with high analog bandwidth (precision timing) and large record depth, in a cost-effective, compact and low-power way. Simply stated, one cannot do better than having a high-fidelity 'oscilloscope on a chip' for every sensor channel. A firs version of the Buffered Large Analog Bandwidth (BLAB1) ASIC has been designed based upon the lessons learned from the development of the Large Analog Bandwidth Recorder and Digitizer with Ordered Readout (LABRADOR) ASIC. While this LABRADOR ASIC has been very successful and forms the readout basis of a generation of new, large-scale radio neutrino detectors, its limited sampling depth is a major drawback. To address this shortcoming, a prototype intended for photodetector readout has been designed and fabricated with 64k deep sampling at multi-GSa/s operation. An evaluation system has been constructed for instrumentation of Time-Of-Propagation (TOP) and focusing DIRC prototypes and test results will be reported.
Date:
June 14, 2011
Creator:
Varner, Gary S.; Ruckman, Larry L.; Schwiening, Jochen & Vavra, Jaroslav
Object Type:
Article
System:
The UNT Digital Library
PILOT-SCALE TEST RESULTS OF A THIN FILM EVAPORATOR SYSTEM FOR MANAGEMENT OF LIQUID HIGH-LEVEL WASTES AT THE HANFORD SITE WASHINGTON USA -11364
A modular, transportable evaporator system, using thin film evaporative technology, is planned for deployment at the Hanford radioactive waste storage tank complex. This technology, herein referred to as a wiped film evaporator (WFE), will be located at grade level above an underground storage tank to receive pumped liquids, concentrate the liquid stream from 1.1 specific gravity to approximately 1.4 and then return the concentrated solution back into the tank. Water is removed by evaporation at an internal heated drum surface exposed to high vacuum. The condensed water stream will be shipped to the site effluent treatment facility for final disposal. This operation provides significant risk mitigation to failure of the aging 242-A Evaporator facility; the only operating evaporative system at Hanford maximizing waste storage. This technology is being implemented through a development and deployment project by the tank farm operating contractor, Washington River Protection Solutions (WRPS), for the Office of River Protection/Department of Energy (ORPIDOE), through Columbia Energy and Environmental Services, Inc. (Columbia Energy). The project will finalize technology maturity and install a system at one of the double-shell tank farms. This paper summarizes results of a pilot-scale test program conducted during calendar year 2010 as part of the ongoing …
Date:
February 14, 2011
Creator:
JE, CORBETT; AR, TEDESCH; RA, WILSON; TH, BECK & J, LARKIN
Object Type:
Article
System:
The UNT Digital Library
Essay: Bob Siemann-SLC Days at SLAC
Bob Siemann was a great experimentalist and an excellent teacher.We will greatly miss him. Bob came to SLAC in early 1991 to work on the Stanford Linear Collider (SLC). The SLC was a challenging accelerator which began operating in the late 1980's but still had numerous obstacles to be overcome years into operation. One of the compounding difficulties was making reproducible measurements, since the stability of the collider was poor and the diagnostics were insufficient. Bob dove into this challenge and helped design experiments and diagnostics that provided further clarity. I first got to know Bob while I was still a graduate student, trying to finish my thesis and performing some experimental studies on the SLC, which, at the time, was proving to be very difficult. Most of my expertise had been in beam theory and simulation. Dealing with the real issues of the accelerator was challenging. Bob helped me understand the difference between systematic and statistical errors, and separate operational issues from the fundamental physics. His way of teaching was not to provide an explanation but to ask enough questions so that I could find the answer on my own - this was the best way to learn. I …
Date:
November 14, 2011
Creator:
Raubenheimer, Tor O.
Object Type:
Article
System:
The UNT Digital Library
Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil
Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. …
Date:
July 14, 2011
Creator:
DeAngelis, Kristen; Allgaier, Martin; Chavarria, Yaucin; Fortney, Julian; Hugenholtz, Phillip; Simmons, Blake et al.
Object Type:
Article
System:
The UNT Digital Library
Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range
A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47, 073602 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A616, 172 (2010)]. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of …
Date:
March 14, 2011
Creator:
Yashchuk, Valeriy V.; Anderson, Erik H.; Barber, Samuel K.; Bouet, Nathalie; Cambie, Rossana; Conley, Raymond et al.
Object Type:
Article
System:
The UNT Digital Library
UNCERTAINTIES OF ANION AND TOC MEASUREMENTS AT THE DWPF LABORATORY
None
Date:
April 14, 2011
Creator:
Edwards, T.
Object Type:
Report
System:
The UNT Digital Library