A 15-T Pulsed Solenoid for a High-Power Target Experiment (open access)

A 15-T Pulsed Solenoid for a High-Power Target Experiment

The MERIT experiment, which ran at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date: June 23, 2008
Creator: Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, F.; Pereira, H.; Titus, P. et al.
Object Type: Article
System: The UNT Digital Library
Achieving Stability Requirements for Nanoprobe and Long Beam Lines at NSLS II. A Comprehensive Study (open access)

Achieving Stability Requirements for Nanoprobe and Long Beam Lines at NSLS II. A Comprehensive Study

Driven by beam stability requirements at the NSLS II synchrotron, such that the desired small beam sizes and high brightness are both realized and stable, a comprehensive study has been launched seeking to provide assurances that stability at the nanometer level at critical x-ray beam-lines, is achievable, given the natural and cultural vibration environment at the selected site. The study consists of (a) an extensive investigation of the site to evaluate the existing ground vibration, in terms of amplitude, frequency content and coherence, and (b) of a numerical study of wave propagation and interaction with the infrastructure of the sensitive lines. The paper presents results from both aspects of the study.
Date: June 23, 2008
Creator: Simos,N.; Fallier, M.; Hill, J.; Berman, L.; Evans-Lutterodt, K. & Broadbent, A.
Object Type: Article
System: The UNT Digital Library
AGS polarized proton operation in run 8. (open access)

AGS polarized proton operation in run 8.

Dual partial snake scheme has been used for the Brookhaven AGS (Alternating Gradient Synchrotron) polarized proton operation for several years. It has provided polarized proton beams with 1.5 x 10{sup 11} intensity and 65% polarization for RHIC spin program. There is still residual polarization loss. Several schemes such as putting horizontal tune into the spin tune gap, and injection-on-the-fly were tested in the AGS to mitigate the loss. This paper presents the experiment results and analysis.
Date: June 23, 2008
Creator: Huang, H.; Ahrens, L.; Bai, M.; Brown, K. A.; Gardner, C.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Air Force Air Refueling: The KC-X Aircraft Acquisition Program (open access)

Air Force Air Refueling: The KC-X Aircraft Acquisition Program

The report discusses the KC-X program which is expected to acquire 179 new, commercial, off-the-shelf airliners modified to accomplish air refueling.
Date: June 23, 2008
Creator: Knight, William; Bolkcom, Christopher & Else, Daniel H.
Object Type: Report
System: The UNT Digital Library
Analysis of intensity instability threshold at transition in RHIC. (open access)

Analysis of intensity instability threshold at transition in RHIC.

The beam intensity of ion beams in RHIC is limited by a fast transverse instability at transition, driven by the machine impedance and electron clouds. For gold and deuteron beams we analyze the dependence of the instability threshold on beam and machine parameters from recent operational data and dedicated experiments. We fit the machine impedance to the experimental data.
Date: June 23, 2008
Creator: Fischer, W.; Blaskiewicz, M.; Cameron, P.; Montag, C. & Ptitsyn, V.
Object Type: Article
System: The UNT Digital Library
Asian Pacific Americans in the United States Congress (open access)

Asian Pacific Americans in the United States Congress

Asian Pacific Americans have served in both houses of Congress representing California, Hawaii, Louisiana, Oregon, Virginia, American Samoa, and Guam. They have served in leadership positions, including committee and subcommittee chairmanships. This report presents information on Senators, Representatives, and Delegates, including party affiliations, length and dates of service, and committee assignments.
Date: June 23, 2008
Creator: Tong, Lorraine H.
Object Type: Report
System: The UNT Digital Library
Asian Pacific Americans in the United States Congress (open access)

Asian Pacific Americans in the United States Congress

This report contains a background about the nine Asian Pacific Americans who served in the first session of the 110th Congress: two Senators, six Representatives, and on delegate.
Date: June 23, 2008
Creator: Tong, Lorraine H.
Object Type: Report
System: The UNT Digital Library
Benchmarking of collimation tracking using RHIC beam loss data. (open access)

Benchmarking of collimation tracking using RHIC beam loss data.

State-of-the-art tracking tools were recently developed at CERN to study the cleaning efficiency of the Large Hadron Collider (LHC) collimation system. In order to estimate the prediction accuracy of these tools, benchmarking studies can be performed using actual beam loss measurements from a machine that already uses a similar multistage collimation system. This paper reviews the main results from benchmarking studies performed with specific data collected from operations at the Relativistic Heavy Ion Collider (RHIC).
Date: June 23, 2008
Creator: Robert-Demolaize,G. & Drees, A.
Object Type: Article
System: The UNT Digital Library
Characterization of Prototype LSST CCDs (open access)

Characterization of Prototype LSST CCDs

The ambitious science goals of the Large Synoptic Survey Telescope (LSST) will be achieved in part by a wide-field imager that will achieve a new level of performance in terms of area, speed, and sensitivity. The instrument performance is dominated by the focal plane sensors, which are now in development. These new-generation sensors will make use of advanced semiconductor technology and will be complemented by a highly integrated electronics package located inside the cryostat. A test laboratory has been set up at Brookhaven National Laboratory (BNL) to characterize prototype sensors and to develop test and assembly techniques for eventual integration of production sensors and electronics into modules that will form the final focal plane. As described in [1], the key requirements for LSST sensors are wideband quantum efficiency (QE) extending beyond lpm in the red, control of point spread function (PSF), and fast readout using multiple amplifiers per chip operated in parallel. In addition, LSST's fast optical system (f71.25) places severe constraints on focal plane flatness. At the chip level this involves packaging techniques to minimize warpage of the silicon die, and at the mosaic level careful assembly and metrology to achieve a high coplanarity of the sensor tiles. In …
Date: June 23, 2008
Creator: O'Connor, P.; Frank, J.; Geary, J. C.; Gilmore, D. K.; Kotov, I.; Radeka, V. et al.
Object Type: Article
System: The UNT Digital Library
Coarse Grained Modeling of The Interface BetweenWater and Heterogeneous Surfaces (open access)

Coarse Grained Modeling of The Interface BetweenWater and Heterogeneous Surfaces

Using coarse grained models we investigate the behavior of water adjacent to an extended hydrophobic surface peppered with various fractions of hydrophilic patches of different sizes. We study the spatial dependence of the mean interface height, the solvent density fluctuations related to drying the patchy substrate, and the spatial dependence of interfacial fluctuations. We find that adding small uniform attractive interactions between the substrate and solvent cause the mean position of the interface to be very close to the substrate. Nevertheless, the interfacial fluctuations are large and spatially heterogeneous in response to the underlying patchy substrate. We discuss the implications of these findings to the assembly of heterogeneous surfaces.
Date: June 23, 2008
Creator: Willard, Adam & Chandler, David
Object Type: Article
System: The UNT Digital Library
Coast Guard: Strategies for Mitigating the Loss of Patrol Boats Are Achieving Results in the Near Term, but They Come at a Cost and Longer Term Sustainability Is Unknown (open access)

Coast Guard: Strategies for Mitigating the Loss of Patrol Boats Are Achieving Results in the Near Term, but They Come at a Cost and Longer Term Sustainability Is Unknown

A letter report issued by the Government Accountability Office with an abstract that begins "The Coast Guard's 110-foot patrol boats are used for a number of missions, such as enforcement of fisheries laws, and the interdiction of migrants and illicit drugs. As part of the Coast Guard's initial plans to replace many of its vessels, it intended to convert its 110-foot patrol boats into 123-foot patrol boats with increased capabilities until the replacement vessel, the Fast Response Cutter (FRC), became operational. However, structural problems on the eight converted 123-foot boats led the Coast Guard to remove these boats from service. Faced with a loss of operational hours, especially in the Coast Guard's Florida-based District 7 where these boats operated, the Coast Guard implemented mitigation strategies to recover lost operational hours. This report provides information on Coast Guard patrol boat operations and, in particular, addresses: (1) operational challenges created by the removal from service of the 123-foot patrol boats and the Coast Guard's strategies for mitigating their loss; (2) effects these mitigation strategies have had on overall Coast Guard operational hours, as well as operating and maintenance costs, patrol boat crews, and mission performance; and (3) issues that could affect the …
Date: June 23, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Comparative Study of Vibration Stability at Operating Light Source Facilities and Lessons Learned in Achieving NSLS II Stability Goals (open access)

Comparative Study of Vibration Stability at Operating Light Source Facilities and Lessons Learned in Achieving NSLS II Stability Goals

In an effort to ensure that the stability goals of the NSLS II will be met once the accelerator structure is set on the selected BNL site a comprehensive evaluation of the ground vibration observed at existing light source facilities has been undertaken. The study has relied on measurement data collected and reported by the operating facilities as well as on new data collected in the course of this study. The primary goal of this comprehensive effort is to compare the green-field conditions that exist in the various sites both in terms of amplitude as well as frequency content and quantify the effect of the interaction of these accelerator facilities with the green-field vibration. The latter represents the ultimate goal of this effort where the anticipated motion of the NSLS II ring is estimated prior to its construction and compared with the required stability criteria.
Date: June 23, 2008
Creator: Simos,N.; Fallier, M. & Amick, H.
Object Type: Article
System: The UNT Digital Library
Copper Prototype Measurements of the HOM, LOM and SOM Couplers for the ILC Crab Cavity (open access)

Copper Prototype Measurements of the HOM, LOM and SOM Couplers for the ILC Crab Cavity

The ILC Crab Cavity is positioned close to the IP and delivered luminosity is very sensitive to the wakefields induced in it by the beam. A set of couplers were designed to couple to and damp the spurious modes of the crab cavity. As the crab cavity operates using a dipole mode, it has different damping requirements from an accelerating cavity. A separate coupler is required for the monopole modes below the operating frequency of 3.9 GHz (known as the LOMs), the opposite polarization of the operating mode (the SOM), and the modes above the operating frequency (the HOMs). Prototypes of each of these couplers have been manufactured out of copper and measured attached to an aluminum nine cell prototype of the cavity and their external Q factors were measured. The results were found to agree well with numerical simulations.
Date: June 23, 2008
Creator: Burt, G.; Ambattu, P. K.; Dexter, A. C.; Bellantoni, L.; Goudket, P.; McIntosh, P. A. et al.
Object Type: Article
System: The UNT Digital Library
The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11 (open access)

The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11

This report analyzes war funding for the Defense Department and tracks funding for USAID and VA Medical funding.
Date: June 23, 2008
Creator: Belasco, Amy
Object Type: Report
System: The UNT Digital Library
Defense Production Act: Purpose and Scope (open access)

Defense Production Act: Purpose and Scope

The Defense Production Act (DPA) was created at the outset of the Korean War to ensure the availability of the nation's industrial resources to meet the national security needs of the United States by granting the President powers to ensure the supply and timely delivery of products, materials, and services to military and civilian agencies. The DPA codifies a robust legal authority given the president to force industry to give priority to national security production and is the statutory underpinning of governmental review of foreign investment in U.S. companies. Since its enactment in 1950, the DPA has been time-limited, undergoing periodic amendment and reauthorization. In 2003, Congress reauthorized the DPA through September 30, 2008.
Date: June 23, 2008
Creator: Else, Daniel H.
Object Type: Report
System: The UNT Digital Library
Dipole magnet for use of RHIC EBIS HEBT line. (open access)

Dipole magnet for use of RHIC EBIS HEBT line.

Construction and magnetic field measurement of dipole magnets for RHIC-EBIS HEBT line have completed. These magnets will be used to guide highly charged ion beams ranging from proton to Uranium provided by a new injector toward the Booster ring in BNL. In this paper, overview of the magnetic design of the dipoles and results of magnetic field measurement are summarized.
Date: June 23, 2008
Creator: Kanesue,T.; Okamura, M.; Ritter, J. & Raparia, D.
Object Type: Article
System: The UNT Digital Library
The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC. (open access)

The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC.

To compensate the effects from the head-on beam-beam interactions in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), an electron lens (elens) is proposed to collide head-on with the proton beam. We used an extended version of SixTrack for multiparticle beam-beam simulation in order to study the effect of the e-lens on the stochastic boundary and also on diffusion. The stochastic boundary was analyzed using Lyapunov exponents and the diffusion was characterized as the increase in the rms spread of the action. For both studies the simulations were performed with and without the e-lens and with full and partial compensation. Using the simulated values of the diffusion an attempt to calculate the emittance growth rate is presented.
Date: June 23, 2008
Creator: Abreu,N.; Beebe-Wang, J.; FischW; Luo, Y. & Robert-Demolaize, G.
Object Type: Article
System: The UNT Digital Library
Electronic Payments: Many Programs Electronically Disburse Federal Benefits, and More Outreach Could Increase Use (open access)

Electronic Payments: Many Programs Electronically Disburse Federal Benefits, and More Outreach Could Increase Use

A letter report issued by the Government Accountability Office with an abstract that begins "Traditionally, federal agencies made benefit payments by paper check, but they faced increased pressure to reduce costs and increase the convenience, security, and timeliness of payment delivery. In response to a 1996 congressional mandate, the U.S. Department of Agriculture's Food Stamp Program implemented Electronic Benefit Transfer (EBT) to distribute food stamps. According to agency evaluations, EBT has reduced program costs and fraud and offered recipients a quick, secure way to receive payment. These results spurred interest in using electronic payment methods for other benefit programs. GAO was asked to report on (1) the extent to which federal benefit programs are using electronic payments, and factors agencies consider for their use and (2) options for increasing the use of electronic payments, particularly the Department of the Treasury's (Treasury) actions to that end. GAO surveyed federal benefit programs identified from two federal databases; reviewed documents, reports, and studies on electronic payments; and interviewed federal and state agency, industry, and consumer representatives."
Date: June 23, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Energy loss of coasting gold ions and deuterons in RHIC. (open access)

Energy loss of coasting gold ions and deuterons in RHIC.

The total energy loss of coasting gold ion beams was measured at RHIC at two energies, corresponding to a gamma of 75.2 and 107.4. We describe the experiment and observations and compare the measured total energy loss with expectations from ionization losses at the residual gas, the energy loss due to impedance and synchrotron radiation. We find that the measured energy losses are below what is expected from free space synchrotron radiation. We believe that this shows evidence for suppression of synchrotron radiation which is cut off at long wavelength by the presence of the conducting beam pipe.
Date: June 23, 2008
Creator: Abreu,N.; Blaskiewicz, M.; Brown, K.A.; Butler, J.J.; FischW; Harvey, M. et al.
Object Type: Article
System: The UNT Digital Library
Equal Employment Opportunity Commission: Sharing Promising Practices and Fully Implementing Strategic Human Capital Planning Can Improve Management of Growing Workload (open access)

Equal Employment Opportunity Commission: Sharing Promising Practices and Fully Implementing Strategic Human Capital Planning Can Improve Management of Growing Workload

A letter report issued by the Government Accountability Office with an abstract that begins "The Equal Employment Opportunity Commission (EEOC), created by title VII of the Civil Rights Act of 1964, promotes equal opportunity in the workplace and enforces federal laws that prohibit employment discrimination on the basis of race, sex, color, religion, national origin, age, and disability. As the nation's primary enforcer of civil rights employment laws, EEOC investigates charges of employment discrimination from the public, litigates major cases, and reaches out to federal agencies and the public to educate and prevent discrimination. EEOC serves every industry, every segment of the population, and every part of the country. While its core mission has not changed since the agency was established more than 40 years ago, EEOC continues to face a range of new challenges in the 21st century, including long-term fiscal constraints, changing demographics, and rapid advances in technology. The federal government overall faces significant human capital challenges, including a retirement wave that will lead to the loss of leadership and institutional knowledge at all levels. EEOC is not immune from this trend. EEOC estimates that within 4 years, all of its current senior executives and senior managers will …
Date: June 23, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Experience with IBS-suppression lattice in RHIC (open access)

Experience with IBS-suppression lattice in RHIC

An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performance of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression.
Date: June 23, 2008
Creator: Litvinenko,V. N.; Luo, Y.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Bai, M. et al.
Object Type: Article
System: The UNT Digital Library
An Experimental Study of Radiation-Induced Demagnetization of Insertion Device Permanent Magnets (open access)

An Experimental Study of Radiation-Induced Demagnetization of Insertion Device Permanent Magnets

High brilliance in the 3GeV new light source NSLS II is obtained from the high magnetic fields in insertion devices (ID). The beam lifetime is limited to 3h by single Coulomb scattering in the Bunch (Touschek effect). This effect occurs everywhere around the circumference and there is unavoidable beam loss in the adjacent low aperture insertion devices. This raises the issue of degradation and damage of the permanent magnetic material by irradiation with high energy electrons and corresponding shower particles. It is expected that IDs, especially those in-vacuum, would experience changes resulting from exposure to gamma rays, x-rays, electrons and neutrons. By expanding an on-going material radiation damage study at BNL the demagnetization effect of irradiation consisting primarily of neutrons, gamma rays and electrons on a set of NdFeB magnets is studied. Integrated doses ranging from several Mrad to a few Grad were achieved at the BNL Isotope Facility with a 112 MeV, 90 {micro}A proton beam. Detailed information on dose distributions as well as on particle energy spectra on the NdFeB magnets was obtained in realistic simulations with the MARS15 Monte-Carlo code. This paper summarizes the results of this study.
Date: June 23, 2008
Creator: Simos,N.; Job, P.K. & Mokhov, N.
Object Type: Article
System: The UNT Digital Library
Feedback damper system for quadrupole oscillations after transition at RHIC. (open access)

Feedback damper system for quadrupole oscillations after transition at RHIC.

The heavy ion beam at RHIC undergoes strong quadrupole oscillations just after it crosses transition, which leads to an increase in bunch length making rebucketing less effective. A feedback system was built to damp these quadrupole oscillations and in this paper the characteristics of the system and the results obtained are presented and discussed.
Date: June 23, 2008
Creator: Abreu, N.; Blaskiewicz, M.; Brennan, J. M. & Schultheiss, C.
Object Type: Article
System: The UNT Digital Library
FEL-based coherent electron cooling for high-energy hadron colliders (open access)

FEL-based coherent electron cooling for high-energy hadron colliders

Cooling intense high-energy hadron beams is a major challenge in modern accelerator physics. Synchrotron radiation is too feeble and two common methods--stochastic and electron cooling--are not efficient in providing significant cooling for high energy, high intensity proton colliders. In this paper they discuss a practical scheme of Coherent Electron Cooling (CeC), which promises short cooling times (below one hour) for intense proton beams in RHIC at 250 GeV or in LHC at 7 TeV. A possibility of CeC using various microwave instabilities was discussed since 1980s. In this paper, they present first evaluation of specific CeC scheme based on capabilities of present-day accelerator technology, ERLs, and high-gain Free-Electron lasers (FELs). They discuss the principles, the main limitations of this scheme and present some predictions for Coherent Electron Cooling in RHIC and the LHC operating with ions or protons, summarized in Table 1.
Date: June 23, 2008
Creator: Litvinenko,V. N. & Derbenev, Y. S.
Object Type: Article
System: The UNT Digital Library