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Beam loading compensation requirement for multibatch coalescing in Fermilab Main Injector (open access)

Beam loading compensation requirement for multibatch coalescing in Fermilab Main Injector

Fermilab collider Run IIa requires 36 proton bunches with intensities 270E9ppb and 36 antiproton bunches with intensities 40-70E9ppb[1]. Currently the proton bunches are produced by coalescing 5-7 53MHz bunches into one 53MHz bunch and repeating this process a total of 36 times. It is necessary to coalesce each group of 5-7 bunches (called a ''batch'') on independent cycles mainly because of beam loading. The beam loading requirements that would allow us to coalesce 4 proton batches at a time are presented.
Date: July 24, 2001
Creator: al., J. Dey et
System: The UNT Digital Library
Beam-target interaction in heavy ion fusion (open access)

Beam-target interaction in heavy ion fusion

The beam-target interaction in heavy ion fusion is theoretically understood, but experimental verification at appropriate beam intensities is not possible using existing accelerators. If fusion-intensity ion beams were to lose significantly less energy in passing through matter than calculated it would increase the cost of heavy ion fusion. In the worst case the cost scaling is such that a 25% decrease in energy loss would increase the cost of the accelerator by roughly 10%. In this paper we show that fundamental considerations place a lower bound on ion energy loss. The lower bound is not significantly less than the expected energy loss obtained from detailed calculations.
Date: January 24, 1979
Creator: Bangerter, R.O.
System: The UNT Digital Library
Beam test of a large area silicon drift detector (open access)

Beam test of a large area silicon drift detector

The results from the tests of the first large area (4 [times] 4 cm[sup 2]) planar silicon drift detector prototype in a pion beam are reported. The measured position resolution in the drift direction is ([sigma]=40 [plus minus] 10)[mu]m.
Date: March 24, 1992
Creator: Castoldi, A.; Chinnici, S.; Gatti, E.; Longoni, A.; Palma, F.; Sampietro, M. (Consiglio Nazionale delle Ricerche, Milan (Italy)) et al.
System: The UNT Digital Library
Beam test of a large area silicon drift detector (open access)

Beam test of a large area silicon drift detector

The results from the tests of the first large area (4 {times} 4 cm{sup 2}) planar silicon drift detector prototype in a pion beam are reported. The measured position resolution in the drift direction is ({sigma}=40 {plus_minus} 10){mu}m.
Date: March 24, 1992
Creator: Castoldi, A.; Chinnici, S.; Gatti, E.; Longoni, A.; Palma, F.; Sampietro, M. et al.
System: The UNT Digital Library
Beam Transport in Dielectric Wall Accelerator for Intensity Modulated Proton Therapy (open access)

Beam Transport in Dielectric Wall Accelerator for Intensity Modulated Proton Therapy

None
Date: August 24, 2011
Creator: Chen, Y.; Blackfield, D.; Nelson, S. D. & Poole, B.
System: The UNT Digital Library
Behavioral Artistry: Examining the Relationship Between the Interpersonal Skills and Effective Practice Repertoires of Applied Behavior Analysis Practitioners (open access)

Behavioral Artistry: Examining the Relationship Between the Interpersonal Skills and Effective Practice Repertoires of Applied Behavior Analysis Practitioners

Article describes study which investigated interpersonal skills associated with the concept of behavioral artistry (BA), a repertoire of practitioner behaviors including care, attentiveness, and creativity, among others, associated with the effective delivery of applied behavior analysis (ABA) treatment.
Date: May 24, 2019
Creator: Callahan, Kevin; Foxx, Richard M.; Swierczynski, Adam; Aerts, Xing; Mehta, Smita S.; McComb, Mary-Ellen et al.
System: The UNT Digital Library
["Behind the Scenes at a Bush 'Sensitivity Session'" article, April 24, 2000] (open access)

["Behind the Scenes at a Bush 'Sensitivity Session'" article, April 24, 2000]

An article, written by Steve Gunderson for Newsweek, about a meeting between Presidential candidate George W. Bush and gay and lesbian Republicans. The piece focuses on an exchange between Gunderson and Bush specifically and Bush's response to the event as a whole.
Date: April 24, 2000
Creator: Gunderson, Steve
System: The UNT Digital Library
Bessel-Zernike Discrete Variable Representation Basis (open access)

Bessel-Zernike Discrete Variable Representation Basis

The connection between the Bessel discrete variable basis expansion and a specific form of an orthogonal set of Jacobi polynomials is demonstrated. These so-called Zernike polynomials provide alternative series expansions of suitable functions over the unit interval. Expressing a Bessel function in a Zernike expansion provides a straightforward method of generating series identities. Furthermore, the Zernike polynomials may also be used to efficiently evaluate the Hankel transform for rapidly decaying functions or functions with finite support.
Date: October 24, 2005
Creator: Cerjan, C J
System: The UNT Digital Library
Better together: Protein partnerships for lineage-specific oil accumulation (open access)

Better together: Protein partnerships for lineage-specific oil accumulation

Article reviews recent evidence that protein–protein interactions in each of the three major phases of oil formation appear to have profound effects on specialized oil accumulation. This article is part of the special issue: Physiology and metabolism (2022).
Date: February 24, 2022
Creator: Busta, Lucas; Chapman, Kent Dean & Cahoon, Edgar B.
System: The UNT Digital Library
BIFUNCTIONAL CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NO BY HYDROCARBONS (open access)

BIFUNCTIONAL CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NO BY HYDROCARBONS

Novel bifunctional catalysts combining two active phases, typically Cu-ZSM-5 and a modifier, were prepared and tested for the selective catalytic reduction of nitrogen oxides using propylene in order to overcome the hindering effects of water typically seen for single-phase catalysts such as Cu-ZSM-5. The catalysts were made by typical preparation techniques, but parameters could be varied to influence the catalyst. The physical characterization of the materials showed that the modification phase was added strictly to the external surface of the zeolite without hindering any internal surface area. Chemical characterization by temperature programmed reactions, DRIFTS and x-ray absorption spectroscopy indicated strong interaction between the two phases, primarily producing materials that exhibited lower reduction temperatures. Two improvements in NOx reduction activity (1000 ppm NO, 1000 ppm C3H6, 2% O2, 30,000 hr-1 GHSV) were seen for these catalysts compared with Cu- ZSM-5: a lower temperature of maximum NOx conversion activity (as low at 250 C), and an enhancement of activity when water was present in the system. The use of a second phase provides a way to further tune the properties of the catalyst in order to achieve mechanistic conditions necessary to maximize NOx remediation.
Date: August 24, 2003
Creator: Neylon, M.; Castagnola, M.; Kropf, A. & Marshall, C.
System: The UNT Digital Library
A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs (open access)

A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs

Three-dimensional reconstruction of ribosome particles from electron micrographs requires selection of many single-particle images. Roughly 100,000 particles are required to achieve approximately 10 angstrom resolution. Manual selection of particles, by visual observation of the micrographs on a computer screen, is recognized as a bottleneck in automated single particle reconstruction. This paper describes an efficient approach for automated boxing of ribosome particles in micrographs. Use of a fast, anisotropic non-linear reaction-diffusion method to pre-process micrographs and rank-leveling to enhance the contrast between particles and the background, followed by binary and morphological segmentation constitute the core of this technique. Modifying the shape of the particles to facilitate segmentation of individual particles within clusters and boxing the isolated particles is successfully attempted. Tests on a limited number of micrographs have shown that over 80 percent success is achieved in automatic particle picking.
Date: June 24, 2003
Creator: Adiga, Umesh P. S.; Malladi, Ravi; Baxter, William & Glaeser, Robert M.
System: The UNT Digital Library
Birds of a Feather: Supporting Secure Systems (open access)

Birds of a Feather: Supporting Secure Systems

Over the past few years Lawrence Livermore National Laboratory has begun the process of moving to a diskless environment in the Secure Computer Support realm. This movement has included many moving targets and increasing support complexity. We would like to set up a forum for Security and Support professionals to get together from across the Complex and discuss current deployments, lessons learned, and next steps. This would include what hardware, software, and hard copy based solutions are being used to manage Secure Computing. The topics to be discussed include but are not limited to: Diskless computing, port locking and management, PC, Mac, and Linux/UNIX support and setup, system imaging, security setup documentation and templates, security documentation and management, customer tracking, ticket tracking, software download and management, log management, backup/disaster recovery, and mixed media environments.
Date: April 24, 2006
Creator: Braswell, H. V., III
System: The UNT Digital Library
BLV-2011 Workshop, September 22-24, 2011 (open access)

BLV-2011 Workshop, September 22-24, 2011

The 3-rd International 3-days Workshop "Baryon and Lepton Number Violations: BLV-2011" took place at Gatlinburg, TN for September 22-24, 2011. Workshop was organized by the International Organizing Committee and had received advice from the International Program Advisory Committee (see Appendix 1). Workshop was co-chaired by Pavel Fileviez Perez (University of Wisconsin) for theory and Yuri Kamyshkov (University of Tennessee) for experiment and local organization. Workshop was supported and sponsored by the University of Tennessee, Indiana University, North Carolina State University together with TUNL, and by the HEP office of the Department of Energy. DOE financial support in this sponsoring grant was $8,000; that was 23% of the overall budget of the Workshop. Remaining 77% were provided by the sponsoring Universities. Workshop sponsors including DOE are shown on the Workshop webpage. There were 90 workshop participants with 52 from US and remaining from Bosnia/Herzegovina (1), Brazil (1), China (1), Columbia (1), France (1), Germany (10), Italy (9), Japan (4), Russian Federation (3), Slovenia (2), Spain (4), and Switzerland (1). Among Workshop participants there were 17 postdocs and young researchers and 11 graduate students. Total 67 talks and 14 posters were presented at Workshop during 3 days of sessions. Appendix 2 shows …
Date: September 24, 2011
Creator: Committee, Y. A. Kamyshkov (University of Tennessee) co-Chair of the Workshop Organizing; Committee, P. Fileviez Perez (University of Wisconsin) co-Chair of the Workshop Organizing; W. M. Snow (Indiana University), member of Workshop Organizing Committee & A.R. Young (North Carolina State University), member of Workshop Organizing Committee
System: The UNT Digital Library
Bounding the Higgs Width Through Interferometry (open access)

Bounding the Higgs Width Through Interferometry

None
Date: May 24, 2013
Creator: Dixon, Lance J. & Li, Ye
System: The UNT Digital Library
Bounds and Estimates for Transport Coefficients of Random and Porous Media with High Contrasts (open access)

Bounds and Estimates for Transport Coefficients of Random and Porous Media with High Contrasts

Bounds on transport coefficients of random polycrystals of laminates are presented, including the well-known Hashin-Shtrikman bounds and some newly formulated bounds involving two formation factors for a two-component porous medium. Some new types of self-consistent estimates are then formulated based on the observed analytical structure both of these bounds and also of earlier self-consistent estimates (of the CPA or coherent potential approximation type). A numerical study is made, assuming first that the internal structure (i.e., the laminated grain structure) is not known, and then that it is known. The purpose of this aspect of the study is to attempt to quantify the differences in the predictions of properties of a system being modeled when such organized internal structure is present in the medium but detailed spatial correlation information may or (more commonly) may not be available. Some methods of estimating formation factors from data are also presented and then applied to a high-contrast fluid-permeability data set. Hashin-Shtrikman bounds are found to be very accurate estimates for low contrast heterogeneous media. But formation factor lower bounds are superior estimates for high contrast situations. The new self-consistent estimators also tend to agree better with data than either the bounds or the CPA …
Date: September 24, 2004
Creator: Berger, E. L.
System: The UNT Digital Library
Brief report from the Tevatron (open access)

Brief report from the Tevatron

The authors report on the B physics prospects from the Fermilab Tevatron, summarizing the B physics goals of the CDF and D0 experiments using their upgraded detectors. They discuss the time schedule for completion of the detector upgrades and summarize the current measurement of the CP violation parameter sin 2{beta} at CDF.
Date: January 24, 2000
Creator: Paulini, M.
System: The UNT Digital Library
Brightness Limitations in Multi-Kiloampere Electron Beam Sources (open access)

Brightness Limitations in Multi-Kiloampere Electron Beam Sources

Heuristic relationships such as the Lawson-Penner criterion, used to scale Free Electron Laser (FEL) amplifier gain and efficiency over orders of magnitude in beam current and brightness, have no fundamental basis. The brightness of a given source is set by practical design choices such as peak voltage, cathode type, gun electrode geometry, and focusing field topology. The design of low emittance, high current electron guns has received considerable attention at Livermore over the past few years. The measured brightnesses of the Experimental Test Accelerator (ETA) and Advanced Test Accelerator (ATA) guns are less than predicted with the EBQ gun design code; this discrepancy is due to plasma effects from the present cold, plasma cathode in the code. The EBQ code is well suited to exploring the current limits of gridless relativistic Pierce columns with moderate current density (<50 A/cm/sup 2/) at the cathode. As EBQ uses a steady-state calculation it is not amenable for study of transient phenomena at the beam head. For this purpose, a Darwin approximation code, DPC, has been written. The main component in our experimental cathode development effort is a readily modified electron gun that will allow us to test many candidate cathode materials, types and …
Date: August 24, 1984
Creator: Barletta, W. A.; Boyd, J. K.; Paul, A. C. & Prono, D. S.
System: The UNT Digital Library
Bubble Counts for Rayleigh-Taylor Instability Using Image Analysis (open access)

Bubble Counts for Rayleigh-Taylor Instability Using Image Analysis

We describe the use of image analysis to count bubbles in 3-D, large-scale, LES [1] and DNS [2] of the Rayleigh-Taylor instability. We analyze these massive datasets by first converting the 3-D data to 2-D, then counting the bubbles in the 2-D data. Our plots for the bubble count indicate there are four distinct regimes in the process of the mixing of the two fluids. We also show that our results are relatively insensitive to the choice of parameters in our analysis algorithms.
Date: January 24, 2007
Creator: Miller, P L; Gezahegne, A G; Cook, A W; Cabot, W H & Kamath, C
System: The UNT Digital Library
Building the World's Fastest Linux Cluster (open access)

Building the World's Fastest Linux Cluster

Imagine having 2,304 Xeon processors running day and night solving complex problems. With a theoretical peak of 11.2 teraflops, that is just what the MCR cluster at Lawrence Livermore National Labs (LLNL) is doing. Over the past several years, Lawrence Livermore National Laboratory has deployed a series of increasingly large and powerful Intel-based Linux clusters. The most significant of these is a cluster known as the MCR (Multiprogrammactic Capability Resource). With 1,152 Intel Xeon (2.4 GHz) dual-processor nodes from Linux NetworX and a high performance interconnect from Quadrics, LTD., the MCR currently ranks third on the 21st Top 500 Supercomputer Sites List and is the fastest Linux cluster in the world. This feat was accomplished with a total system cost (hardware including maintenance, in-reconnect, global file system storage) of under $14 million. Although production clusters like the MCR are still custom built supercomputers that require as much artistry as skill, the experiences of LLNL have helped clear an important path for other clusters to follow.
Date: October 24, 2003
Creator: Goldstone, R & Seager, M
System: The UNT Digital Library
Bunch Length Measurements using Coherent Radiation (open access)

Bunch Length Measurements using Coherent Radiation

The accelerating field that can be obtained in a beam-driven plasma wakefield accelerator depends on the current of the electron beam that excites the wake. In the E-167 experiment, a peak current above 10 kA will be delivered at a particle energy of 28 GeV. The bunch has a length of a few ten micrometers and several methods are used to measure its longitudinal profile. Among these, autocorrelation of coherent transition radiation (CTR) is employed. The beam passes a thin metallic foil, where it emits transition radiation. For wavelengths greater than the bunch length, this transition radiation is emitted coherently. This amplifies the long-wavelength part of the spectrum. A scanning Michelson interferometer is used to autocorrelate the CTR. However, this method requires the contribution of many bunches to build an autocorrelation trace. The measurement is influenced by the transmission characteristics of the vacuum window and beam splitter. We present here an analysis of materials, as well as possible layouts for a single shot CTR autocorrelator.
Date: June 24, 2005
Creator: Ischebeck, Rasmus; Barnes, Christopher; Blumenfeld, Ian; Decker, Franz-Josef; Hogan, Mark; Iverson, Richard H. et al.
System: The UNT Digital Library
Calculation of Fragmentation Functions in Two-Hadron Semi-Inclusive Processes. (open access)

Calculation of Fragmentation Functions in Two-Hadron Semi-Inclusive Processes.

We investigate the properties of interference fragmentation functions arising from the emission of two leading hadrons inside the same jet for inclusive lepton-nucleon deep inelastic scattering. Using an extended spectator model for the mechanism of the hadronization, we give a complete calculation and numerical estimates for the examples of a proton-pion pair produced with invariant mass on the Roper resonance, and of two pions produced with invariant mass close to the {rho} mass. We discuss azimuthal angular dependence of the leading order cross section to point up favourable conditions for extracting transversity from experimental data.
Date: April 24, 2001
Creator: Bianconi, A.; Boffi, S.; Boer, D.; Jakob, R. & Radici, M.
System: The UNT Digital Library
Calibration of a High Resolution Grating Soft X-ray Spectrometer (open access)

Calibration of a High Resolution Grating Soft X-ray Spectrometer

None
Date: August 24, 2010
Creator: Magee, E. W.; Dunn, J.; Brown, G. V.; Cone, K. V.; Park, J.; Porter, F. S. et al.
System: The UNT Digital Library
A Camera for Coherent Diffractive Imaging and Holography With a Soft-X-Ray Free Electron Laser (open access)

A Camera for Coherent Diffractive Imaging and Holography With a Soft-X-Ray Free Electron Laser

We describe a camera to record coherent scattering patterns with a soft-X-ray free-electron laser. The camera consists of a laterally-graded multilayer mirror which reflects the diffraction pattern onto a CCD detector. The mirror acts as a bandpass filter both for wavelength and angle, which isolates the desired scattering pattern from non-sample scattering or incoherent emission from the sample. The mirror also solves the particular problem of the extreme intensity of the FEL pulses, which are focused to greater than 10{sup 14} W/cm{sup 2}. The strong undiffracted pulse passes through a hole in the mirror and propagates on to a beam dump at a distance behind the instrument rather than interacting with a beamstop placed near the CCD. The camera concept is extendable for the full range of the fundamental wavelength of the FLASH FEL (i.e. between 6 nm and 60 nm) and into the water window. We have fabricated and tested various multilayer mirrors for wavelengths of 32 nm, 16 nm, 13.5 nm, and 4.5 nm. At the shorter wavelengths mirror roughness must be minimized to reduce scattering from the mirror. We have recorded over 30,000 diffraction patterns at the FLASH free-electron laser with no observable mirror damage or degradation …
Date: September 24, 2007
Creator: Bajt, S.; Chapman, H. N.; Spiller, E.; Alameda, J.; Woods, B.; Frank, M. et al.
System: The UNT Digital Library
Can cross sections be accurately known for priori? (open access)

Can cross sections be accurately known for priori?

Distinct maxima and minima in the neutron total cross section uncertainties were observed in our large scale covariance calculations using a spherical optical potential. In this contribution we investigate the physical origin of this oscillating structure. Specifically, we analyze the case of neutron reactions on {sup 56}Fe, for which total cross section uncertainties are characterized by the presence of five distinct minima at 0.1, 1.1, 5, 25, and 70 MeV. To investigate their origin, we calculated total cross sections by perturbing the real volume depth V{sub v} by its expected uncertainty {+-}{Delta}V{sub v}. Inspecting the effect of this perturbation on the partial wave cross sections we found that the first minimum (at 0.1 MeV) is exclusively due to the contribution of the s-wave. On the other hand, the same analysis at 1.1 MeV showed that the minimum is the result of the interplay between s-, p-, and d-waves; namely the change in the s-wave happens to be counterbalanced by changes in the p- and d-waves. Similar considerations can be extended for the third minimum, although it can be also explained in terms of the Ramsauer effect as well as the other ones (at 25 and 70 MeV). We discuss the …
Date: June 24, 2008
Creator: Pigni, M. T.; Dietrich, F. S.; Herman, M. & Oblozinsky, P.
System: The UNT Digital Library