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Modeling the Market Potential of Hydrogen from Wind and Competing Sources (open access)

Modeling the Market Potential of Hydrogen from Wind and Competing Sources

Developed from the Wind Deployment Systems (WinDS) model, the Hydrogen Deployment Systems (HyDS) model is a computer model of U.S. market expansion of hydrogen production from wind and other sources over the next 50 years. The WinDS model was developed in 2003 to model the expansion of generation and transmission capacity in the U.S. electric sector spanning the next 50 years. It minimizes system-wide costs of meeting loads, reserve requirements, and emission constraints by building and operating new generators and transmission in 26 two-year periods from 2000 to 2050. While it includes all major types of conventional generators, the WinDS model focuses on addressing the market issues of greatest significance to wind-specifically issues of electricity transmission and intermittency.
Date: May 1, 2005
Creator: Short, Walter; Blair, Nate & Heimiller, Donna
Object Type: Article
System: The UNT Digital Library
Deterioration of the skew quadrupole moment in Tevatron dipoles over time (open access)

Deterioration of the skew quadrupole moment in Tevatron dipoles over time

During the 20 years since it was first commissioned, the Fermilab Tevatron has developed strong coupling between the two transverse degrees of freedom. A circuit of skew quadrupole magnets is used to correct for coupling and, though capable, its required strength has increased since 1983 by more than an order of magnitude. In more recent years changes to the Tevatron for colliding beams operation have altered the skew quadrupole corrector distribution and strong local coupling become evident, often encumbering routine operation during the present physics run. Detailed magnet measurements were performed on each individual magnet during construction, and in early 2003 it was realized that measurements could be performed on the magnets in situ which could determine coil movements within the iron yoke since the early 1980's. It was discovered that the superconducting coils had become vertically displaced relative to their yokes since their construction. The ensuing systematic skew quadrupole field introduced by this displacement accounts for the required corrector settings and observed beam behavior. An historical account of the events leading to this discovery and progress toward its remedy are presented.
Date: May 1, 2005
Creator: Syphers, M. J. & Harding, D. J.
Object Type: Article
System: The UNT Digital Library
Towards a Wind Energy Climatology at Advanced Turbine Hub-Heights: Preprint (open access)

Towards a Wind Energy Climatology at Advanced Turbine Hub-Heights: Preprint

Measurements of wind characteristics over a wide range of heights up to and above 100 m are useful to: (1) characterize the local and regional wind climate; (2) validate wind resource estimates derived from numerical models; and (3) evaluate changes in wind characteristics and wind shear over the area swept by the blades. Developing wind climatology at advanced turbine hub heights for the United States benefits wind energy development. Tall tower data from Kansas, Indiana, and Minnesota (which have the greatest number of tall towers with measurement data) will be the focus of this paper. Analyses of data from the tall towers will start the process of developing a comprehensive climatology.
Date: May 1, 2005
Creator: Schwartz, M. & Elliott, D.
Object Type: Article
System: The UNT Digital Library

Controlled Hydrogen Fleet & Infrastructure Analysis

A PowerPoint presentation given as part of the 2005 Hydrogen Program Review, May 24, 2005, in Washington, D.C.
Date: May 1, 2005
Creator: Wipke, K.
Object Type: Presentation
System: The UNT Digital Library
Wind Energy Myths (open access)

Wind Energy Myths

This two-sided fact sheet succinctly outlines and counters the top misconceptions about wind energy. It is well suited for general audiences.
Date: May 1, 2005
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Beauty production cross section measurements at E(cm) = 1.96-TeV (open access)

Beauty production cross section measurements at E(cm) = 1.96-TeV

The RunII physics program at the Tevatron started in spring 2001 with protons and antiprotons colliding at an energy of {radical}s = 1.96 TeV, and it is carrying on with more than 500 pb{sup -1} of data as collected by both the CDF and D0 experiments. Recent results on beauty production cross section measurements are here reported.
Date: May 1, 2005
Creator: D'Onofrio, Monica & U., /Geneva
Object Type: Article
System: The UNT Digital Library
First-principles simulation and comparison with beam tests for transverse instabilities and damper performance in the Fermilab Main Injector (open access)

First-principles simulation and comparison with beam tests for transverse instabilities and damper performance in the Fermilab Main Injector

An end-to-end performance calculation and comparison with beam tests was performed for the bunch-by-bunch digital transverse damper in the Fermilab Main Injector. Time dependent magnetic wakefields responsible for ''Resistive Wall'' transverse instabilities in the Main Injector were calculated with OPERA-2D using the actual beam pipe and dipole magnet lamination geometry. The leading order dipole component was parameterized and used as input to a bunch-by-bunch simulation which included the filling pattern and injection errors experienced in high-intensity operation of the Main Injector. The instability growth times, and the spreading of the disturbance due to newly misinjected batches was compared between simulations and beam data collected by the damper system. Further simulation models the effects of the damper system on the beam.
Date: May 1, 2005
Creator: Nicklaus, Dennis; Foster, G. William & Kashikhin, Vladimir
Object Type: Article
System: The UNT Digital Library
Progress on using NEA cathodes in an RF gun (open access)

Progress on using NEA cathodes in an RF gun

RF guns have proven useful in multiple accelerator applications, and are an attractive electron source for the ILC. Using a NEA GaAs photocathode in such a gun allows for the production of polarized electron beams. However the lifetime of a NEA cathode in this environment is reduced by ion and electron bombardment and residual gas oxidation. We report progress made with studies to produce a RF gun using a NEA GaAs photocathode to produce polarized electron beams. We discuss simulations of ion back bombardment and attempts to reduce the residual gas pressure in the gun are discussed. Future directions are also discussed.
Date: May 1, 2005
Creator: Anderson, T.; Edwards, H.; Bluem, H.; Schultheiss, T.; Sinclair, C. & Huening, M.
Object Type: Article
System: The UNT Digital Library
Searches for the standard model Higgs boson at the Tevatron (open access)

Searches for the standard model Higgs boson at the Tevatron

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.
Date: May 1, 2005
Creator: Dorigo, Tommaso & U., /Padua
Object Type: Article
System: The UNT Digital Library
Status of slip stacking at Fermilab Main Injector (open access)

Status of slip stacking at Fermilab Main Injector

In order to achieve an increase in proton intensity, the Fermilab Main Injector (MI) will use a stacking process called ''slip stacking'' [1]. The intensity will be doubled by injecting one train of bunches at a slightly lower energy, another at a slightly higher energy, then bringing them together for the final capture. Beam studies have been performed for this process and we have already verified that, at least for low beam intensities, the stacking procedure works as expected [2]. For high intensity operation, development work of the feedback and feedforward systems was done during the last machine shut down, from August to November 2004 [3].
Date: May 1, 2005
Creator: Seiya, K.; Berenc, T.; Dey, J.; Chase, B.; Rivetta, C.; Kourbanis, I. et al.
Object Type: Article
System: The UNT Digital Library
Tevatron beam position monitor upgrade (open access)

Tevatron beam position monitor upgrade

The Tevatron Beam Position Monitor (BPM) readout electronics and software have been upgraded to improve measurement precision, functionality and reliability. The original system, designed and built in the early 1980's, became inadequate for current and future operations of the Tevatron. The upgraded system consists of 960 channels of new electronics to process analog signals from 240 BPMs, new front-end software, new online and controls software, and modified applications to take advantage of the improved measurements and support the new functionality. The new system reads signals from both ends of the existing directional stripline pickups to provide simultaneous proton and antiproton position measurements. Measurements using the new system are presented that demonstrate its improved resolution and overall performance.
Date: May 1, 2005
Creator: Wolbers, Stephen; Banerjee, B.; Barker, B.; Bledsoe, S.; Boes, T.; Bowden, M. et al.
Object Type: Article
System: The UNT Digital Library
Betatron tune spread generation and differential chromaticity control by octupole families at Tevatron (open access)

Betatron tune spread generation and differential chromaticity control by octupole families at Tevatron

Existing Tevatron octupoles have been rearranged into four functional families. Two of these families generate betatron tune spreads in the vertical and horizontal planes whereas the other two control the differential chromaticity between the proton and antiproton helices. The calculated effect on the tunes and chromaticity is compared with direct measurements. Analytical formulas for betatron tune distribution functions are presented.
Date: May 1, 2005
Creator: Ivanov, P. M.; Alexahin, Y.; Annala, J.; Lebedev, V. A. & /Fermilab
Object Type: Article
System: The UNT Digital Library
A Hardware transverse beam frequency response simulator (open access)

A Hardware transverse beam frequency response simulator

We built an electronic instrument that can mimic the transverse beam frequency response. The instrument consists of (1) a time delay circuit with an analog-to-digital converter (ADC) which contains a first-in-first-out random assess memory (FIFO RAM) and a digital-to-analog converter (DAC); (2) a variable phase shifter circuit which is based on an all pass filter with a bandwidth of 25kHz to 30kHz and (3) a commutating filter which is a nonlinear band pass filter. With this instrument, we can dynamically adjust the betatron tune, the synchrotron tune, and the chromaticity. Using this instrument, we are able to test other beam systems without using actual beam.
Date: May 1, 2005
Creator: Ning, J. & Tan, C. Y.
Object Type: Article
System: The UNT Digital Library
Studies of the chromaticity, tune and coupling drift in the Tevatron (open access)

Studies of the chromaticity, tune and coupling drift in the Tevatron

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. Controlling the behavior of the tune, coupling, and chromaticity is an important part of reducing beam loss at injection and at the start of the Tevatron ramp. 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, tunes, and coupling during the injection porch. In some cases 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 magnetic measurements conducted in spare Tevatron dipoles.
Date: May 1, 2005
Creator: Martens, Michael A.; Annala, Jerry; Bauer, Pierre; Shiltsev, Vladimir & Velev, Gueorgui
Object Type: Article
System: The UNT Digital Library
Iso-adiabatic merging of pbar stacks in the Fermilab Recycler (open access)

Iso-adiabatic merging of pbar stacks in the Fermilab Recycler

Considerable longitudinal emittance (LE) dilution is seen during merging of two stacks of pbars in the Fermilab Recycler. The emittance dilution results from the sequence of RF manipulations used for merging. Here I present a new scheme for merging two stacks adiabatically. This involves energy matching of the two stacks before merging. An analytical expression is derived for energy matching condition. The scheme is illustrated with multi-particle beam dynamics simulations and beam measurements. The beam experiments have shown that one can preserve the emittance to better than 15%.
Date: May 1, 2005
Creator: Bhat, C. M.
Object Type: Article
System: The UNT Digital Library
B0(S) mixing, lifetime difference and rare decays at the Tevatron (open access)

B0(S) mixing, lifetime difference and rare decays at the Tevatron

Recent results on B{sub s}{sup 0} mixing, lifetime difference and rare decays obtained by the CDF and D0 collaborations using the data samples collected at the Tevatron Collider in the period 2002-2005 are presented.
Date: May 1, 2005
Creator: Burdin, Sergey
Object Type: Article
System: The UNT Digital Library
FEASIBILITY OF MEASURING IRON IN VIVO USING FAST 14 MEV NEUTRONS. (open access)

FEASIBILITY OF MEASURING IRON IN VIVO USING FAST 14 MEV NEUTRONS.

In this short report, I reassess the feasibility of measuring iron in vivo in the liver and heart of thalassemia patients undergoing chelation therapy. Despite the multiplicity of analytical methods for analyzing iron, only two, magnetic resonance imaging, and magnetic susceptibility, are suitable for in vivo applications, and these are limited to the liver because of the heart's beat. Previously, a nuclear method, gamma-resonance scattering, offered a quantitative measure of iron in these organs; however, it was abandoned because it necessitated a nuclear reactor to produce the radioactive source. I reviewed and reassessed the status of two alternative nuclear methods, based on iron spectroscopy of gamma rays induced by fast neutron inelastic scattering and delayed activation in iron. Both are quantitative methods with high specificity for iron and adequate penetrating power to measure it in organs sited deep within the human body. My experiments demonstrated that both modalities met the stated qualitative objectives to measure iron. However, neutron dosimetry revealed that the intensity of the neutron radiation field was too weak to reliably assess the minimum detection limits, and to allow quantitative extrapolations to measurements in people. A review of the literature, included in this report, showed that these findings …
Date: May 1, 2005
Creator: WIELOPOLSKI, L.
Object Type: Report
System: The UNT Digital Library
Development of the superconducting 3.9-GHz accelerating cavity at Fermilab (open access)

Development of the superconducting 3.9-GHz accelerating cavity at Fermilab

A superconducting third harmonic 3.9 GHz accelerating cavity was proposed to improve the beam quality in the TTF-like photoinjector [1]. Fermilab has developed, built and tested several prototypes, including two copper 9-cell cavities, one niobium 3-cell cavity, and one 9-cell cavity. The helium vessel and frequency tuner for the 9-cell cavity was built and tested as well. In cold tests, we achieved a peak surface magnetic field of {approx}100mT, well above the 70mT specification. The accelerating gradient was likely limited by thermal breakdown. Studies of the higher order modes in the cavity revealed that the existing cavity design with two HOM couplers will provide sufficient damping of these modes. In this paper we discuss the cavity design, results of the studies and plans for further development.
Date: May 1, 2005
Creator: Arkan, T.; Bauer, P.; Bellantoni, L.; Boffo, C.; Borissov, E.; Carter, H. et al.
Object Type: Article
System: The UNT Digital Library
Top physics results at CDF (open access)

Top physics results at CDF

The most recent results on top quark physics at CDF are reported. Measurements of cross-section and mass are presented, and the status of single top quark production searches are discussed. The results obtained from probing various top quark properties are also presented.
Date: May 1, 2005
Creator: Vickey, Trevor
Object Type: Article
System: The UNT Digital Library
Top physics results from CDF (open access)

Top physics results from CDF

The top quark is by far the most massive fundamental particle observed so far, and the study of its properties is interesting for several reasons ranging from its possible special role in electroweak symmetry breaking to its sensitivity to physics beyond the Standard Model. They present recent top physics results from CDF based on 160-320 pb{sup -1} of p{bar p} collision data at {radical}s = 1.96 TeV. The t{bar t} cross section and the top mass have been measured in different decay channels and using different methods. they have searched for evidence of single top production, setting upper limits on its production rate. Other results shown in this conference include studies of the polarization of W bosons from top decays, a search for charged Higgs decaying from top, and a search for additional heavy t' quarks.
Date: May 1, 2005
Creator: Gomez, Gervasio
Object Type: Article
System: The UNT Digital Library
Simulations of an acceleration scheme for producing high intensity and low emittance antiproton beam for Fermilab collider operation (open access)

Simulations of an acceleration scheme for producing high intensity and low emittance antiproton beam for Fermilab collider operation

During Fermilab collider operation, the Main Injector (MI) provides high intensity and low emittance proton and antiproton beams for the Tevatron. The present coalescing scheme for antiprotons in the Main Injector yields about a factor of two increase in the longitudinal emittance and a factor of 5% to 20% decrease in intensity before injection to the Tevatron. In order to maximize the integrated luminosity delivered to the collider experiments, it is important to minimize the emittance growth and maximize the intensity of the MI beam. To this end, a new scheme using a combination of 2.5 MHz and 53 MHz accelerations has been developed and tested. This paper describes the full simulation of the new acceleration scheme, taking account of space charge, 2.5 MHz and 53 MHz beam loading, and the effect of residual 53 MHz rf voltage during 2.5 MHz acceleration and rf manipulations. The simulations show the longitudinal emittance growth at the 10% level with no beam loss. The experimental test of the new scheme is reported in another PAC05 paper.
Date: May 1, 2005
Creator: Wu, Vincent; Bhat, C. M. & MacLachlan, J. A.
Object Type: Article
System: The UNT Digital Library
Fermilab Recycler damper requirements and design (open access)

Fermilab Recycler damper requirements and design

The design of transverse dampers for the Fermilab Recycler storage ring is described. An observed instability and analysis of subsequent measurements where used to identify the requirements. The digital approach being implemented is presented.
Date: May 1, 2005
Creator: Crisp, J.; Hu, M.; Tupikov, V. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Modeling heavy ion ionization loss in the MARS15 code (open access)

Modeling heavy ion ionization loss in the MARS15 code

The needs of various accelerator and space projects stimulated recent developments to the MARS Monte Carlo code. One of the essential parts of those is heavy ion ionization energy loss. This paper describes an implementation of several corrections to dE/dx in order to take into account the deviations from the Bethe theory at low and high energies as well as the effect of a finite nuclear size at ultrarelativistic energies. Special attention is paid to the transition energy region where the onset of the effect of a finite nuclear size is observed. Comparisons with experimental data and NIST data are presented.
Date: May 1, 2005
Creator: Rakhno, I. L.; Mokhov, N. V. & Striganov, S. I.
Object Type: Article
System: The UNT Digital Library
Searches for non-SM Higgs at Tevatron (open access)

Searches for non-SM Higgs at Tevatron

We sent the non-standard model Higgs boson searches at both D0 and CDF experiments. We concentrate on three topics, reported by D0 and CDF recently: the searches for the minimal supersymmetric Higgs boson using p{bar p} {yields} hb{bar b} {yields} b{bar b}b{bar b} and p{bar p} {yields} hX {yields} {tau}{tau}X, and for long-lived doubly charged Higgs boson.
Date: May 1, 2005
Creator: Tomoto, Makoto
Object Type: Article
System: The UNT Digital Library