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Accelerating and Colliding Polarized Protons in RHIC With Siberian Snakes (open access)

Accelerating and Colliding Polarized Protons in RHIC With Siberian Snakes

We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180{sup o} about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV. We report on our experiences during commissioning and operation of collider with polarized protons.
Date: June 2, 2002
Creator: Roser, T.; Ahrens, L.; Alessi, J.; Bai, M.; Beebe-Wang, J.; Brennan, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Agent-Based Mediation and Cooperative Information Systems (open access)

Agent-Based Mediation and Cooperative Information Systems

This report describes the results of research and development in the area of communication among disparate species of software agents. The two primary elements of the work are the formation of ontologies for use by software agents and the means by which software agents are instructed to carry out complex tasks that require interaction with other agents. This work was grounded in the areas of commercial transport and cybersecurity.
Date: June 2, 2002
Creator: PHILLIPS, LAURENCE R.; LINK, HAMILTON E. & GOLDSMITH, STEVEN Y.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 104, No. 66, Ed. 1 Sunday, June 2, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 66, Ed. 1 Sunday, June 2, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 2, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Alvin Sun-Advertiser (Alvin, Tex.), Vol. 111, No. 43, Ed. 1 Sunday, June 2, 2002 (open access)

Alvin Sun-Advertiser (Alvin, Tex.), Vol. 111, No. 43, Ed. 1 Sunday, June 2, 2002

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: June 2, 2002
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Analysis of Beam Induced Pressure Increases in Rhic Warm Vacuum Sections. (open access)

Analysis of Beam Induced Pressure Increases in Rhic Warm Vacuum Sections.

With increasing intensity of gold and proton beams during recent RHIC operations, pressure rises of several decades were observed at a few RHIC warm vacuum sections. The pressure increases were analyzed and compared with the beam parameters such as ion species, bunch intensity, total intensity, number ofbunches, bunch spacing and beam loss. Most of these pressure increases were found to be consistent with those induced by either beam loss and/or electron multipacting.
Date: June 2, 2002
Creator: Hseuh, H. C.; Smart, L. A. & Zhang, S. Y.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 188, Ed. 1 Sunday, June 2, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 188, Ed. 1 Sunday, June 2, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 2, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam Diffusion Studies at RHIC (open access)

Beam Diffusion Studies at RHIC

None
Date: June 2, 2002
Creator: Fliller, R. P., III; Drees, A.; Gassner, D.; McIntyre, G.; Peggs, S. & Trbojevic, D.
Object Type: Article
System: The UNT Digital Library
Clean Air Act Issues in the 107th Congress (open access)

Clean Air Act Issues in the 107th Congress

In the 107th Congress, the most prominent air quality issue has been whether state and federal regulations designed to protect air quality are having a negative impact on energy production, and, if so, whether legislation should be enacted to reform such regulations. The early discussion focused primarily on California, but with the release of the Administration’s energy policy recommendations in May 2001 and subsequent congressional action, attention shifted to issues more national in scope.
Date: June 2, 2002
Creator: McCarthy, James E.
Object Type: Report
System: The UNT Digital Library
Commissioning Cni Proton Polarimeters in Rhic. (open access)

Commissioning Cni Proton Polarimeters in Rhic.

Two polarimeters based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region have been installed and commissioned in the Blue and Yellow rings of RHIC during the first RHIC polarized proton collider run. Each polarimeter consists of ultra-thin carbon targets and six silicon detectors. With newly developed wave form digitizers, they provide fast and reliable polarization information for both rings.
Date: June 2, 2002
Creator: Huang, H.; Bravar, A.; Li, Z.; MacKay, W. W.; Makdisi, Y.; Rescia, S. et al.
Object Type: Article
System: The UNT Digital Library
Commissioning of RHIC at 100 GEV / Nucleon (open access)

Commissioning of RHIC at 100 GEV / Nucleon

This report describes commissioning of the Relativistic Heavy Ion Collider (RHIC) for 100 GeV/nucleon collisions at designed luminosity. To achieve these goals new systems had to be commissioned: Gamma-t transition crossing jump quadrupoles, rebucketing with the new RF storage cavities, phase lock loop feedback, betatron and crystal collimation, beta squeeze along the ramp, Siberian snake magnets for the proton polarization run, AC dipole system chromaticity measurements along the acceleration ramp, orbit correction, new ramp management system, upgraded sequencer, new data instrumentation and logger acquisition system etc.
Date: June 2, 2002
Creator: Trbojevic, D.; Ahrens, L.; Blaskiewicz, M.; Brennan, J. M.; Bai, M.; Cameron, P. et al.
Object Type: Article
System: The UNT Digital Library
Comparison Between the Predictions and Measurements for the Beam Gas Interactions During the Last Gold and Proton Runs in RHIC. (open access)

Comparison Between the Predictions and Measurements for the Beam Gas Interactions During the Last Gold and Proton Runs in RHIC.

The last gold-gold and polarized proton-proton collision runs were performed at energies of 100 GeV/nucleon. The beam gas interactions in RHIC are very important for the beam lifetime in RHIC. In this report the lifetime predicted by pressure data differences between the beams ON and beams OFF, at the energies of 100 GeV/nucleon. are compared to the predictions for the beam gas interaction and beam lifetimes.
Date: June 2, 2002
Creator: Trbojevic, D.; Hseuh, H. C.; Fischer, W.; Zhang, S. Y. & MacKay, W. W.
Object Type: Article
System: The UNT Digital Library
Coupling Measurement and Correction at Rhic. (open access)

Coupling Measurement and Correction at Rhic.

Coupling correction at RHIC has been operationally achieved through a two-step process: using local triplet skew quadrupoles to compensate coupling corn rolled low-beta triplet quadrupoles, and minimizing the tune separation and residual coupling with orthogonal global skew quadrupole families. An application has been developed for global correction that allows skew quadrupole tuning and tune display with a choice of different tune measurement techniques, including tune-meter, Schottky and phase lock loop (PLL). Coupling effects have been analysed by using 1024-turn (TBT) information from the beam position monitor (BPM) system. These data allow the reconstruction of the off-diagonal terms of the transfer matrix, a measure of global coupling. At both injection and storage energies, coordination of tune meter kicks with TBT acquisition at 322 BPM's in each ring allows the measurement of local coupling at all BPM locations.
Date: June 2, 2002
Creator: Pilat, F.; Beebe-Wang, J.; Fischer, W.; Ptitsyn, V. & Satogata, T.
Object Type: Article
System: The UNT Digital Library
Creating Interoperable Meshing and Discretization Software: The Terascale Simulation Tools and Technology Center (open access)

Creating Interoperable Meshing and Discretization Software: The Terascale Simulation Tools and Technology Center

We present an overview of the technical objectives of the Terascale Simulation Tools and Technologies center. The primary goal of this multi-institution collaboration is to develop technologies that enable application scientists to easily use multiple mesh and discretization strategies within a single simulation on terascale computers. The discussion focuses on our efforts to create interoperable mesh generation tools, high-order discretization techniques, and adaptive meshing strategies.
Date: June 2, 2002
Creator: Brown, D.; Freitag, L. & Glimm, J.
Object Type: Article
System: The UNT Digital Library
Crystal Collimation at Rhic. (open access)

Crystal Collimation at Rhic.

For the year 2001 run, a bent crystal was installed in the yellow ring of the Relativistic Heavy Ion Collider (RHIC). The crystal forms the first stage of a two stage collimation system. By aligning the crystal to the beam, halo particles are channeled through the crystal and deflected into a copper scraper. The purpose is to reduce beam halo with greater efficiency than with a scraper alone. In this paper we present the first results from the use of the crystal collimator. We compare the crystal performance under various conditions, such as different particle species, and beta functions.
Date: June 2, 2002
Creator: Fliller, R. P., III; Drees, A.; Gassner, D.; Hammons, L.; McIntyre, G.; Peggs, S. et al.
Object Type: Article
System: The UNT Digital Library
Design of the RCMS Lattice Optics (open access)

Design of the RCMS Lattice Optics

THE RAPID CYCLING MEDICAL SYNCHROTRON (RCMS) IS DESIGNED TO BE A VERY LIGHT AND INEXPENSIVE ACCELERATOR. THIS IS POSSIBLE DUE TO THE SMALL BEAM SIZE THAT HAS BEEN CHOSEN EARLY DURING THE DESIGN STAGE. THIS CHOICE HAS IMPLICATIONS IN THE DESIGN OF THE LATTICE OPTICS. IN THIS PAPER, WE PRESENT AN OVERVIEW OF THE RCMS OPTICS LATTICE, THE KIND OF MAGNETS TO BE USED AND ALSO A DESCRIPTION OF A SPECIAL OPTIC MODULE THAT MATCHES THE ROTATING GANTRY WITH THE REST OF THE FIXED ACCELERATOR. TECHNIQUESDEVELOPED TO WIN ADDITIONAL SPACE BETWEEN QUADRUPOLES WITHOUT DISTRUBING BETA FUNCTIONS ARE ALSO PRESENTED.
Date: June 2, 2002
Creator: Cardona, J.; Kewisch, J. & Peggs, S.
Object Type: Article
System: The UNT Digital Library
Determination of Linear and Non Linear Components in Rhic Interaction Regions From Difference Orbit Measurements. (open access)

Determination of Linear and Non Linear Components in Rhic Interaction Regions From Difference Orbit Measurements.

None
Date: June 2, 2002
Creator: Cardona, J.; Peggs, S.; Pilat, F.; Ptitsyn, V. & Satogata, T.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, June 2, 2002 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, June 2, 2002

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: June 2, 2002
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Fixed Field Alternating Gradient Lattice Design Without Opposite Bend. (open access)

Fixed Field Alternating Gradient Lattice Design Without Opposite Bend.

This report presents an attempt of the lattice design with a fixed field alternating gradient (FFAG) magnets without the usual opposite bends. It should allow particle acceleration through a small aperture. An example was made for the muon beam acceleration in an energy range 10-20 GeV with distributed RF cavities. The dispersion function for the central energy of 15 GeV has maximum value of the order of 7 cm. The lattice is composed of a combined function elements and sextupoles. We present the magnet configuration, orbit, chromaticities, tunes, and betatron function dependence on momentum (energies) during acceleration. For the lattice design we used SYNCH an MAD programs. For these large momentum offsets {delta}p/p = +-33% we found discrepancies between analytical and codes' results. This will be corrected in the new versions of codes (MAD-X). Because of uncertainties of the programs MAD and SYNCH some details of the presented results might not be correct.
Date: June 2, 2002
Creator: Trbojevic, D.; Blaskiewicz, M.; Courant, E. D. & Garren, A.
Object Type: Article
System: The UNT Digital Library
A Heavy Ion Microbeam Facility Using Micron Resolution Detectors for 3 GEV/Nucleon Beams (open access)

A Heavy Ion Microbeam Facility Using Micron Resolution Detectors for 3 GEV/Nucleon Beams

None
Date: June 2, 2002
Creator: Brown, K. A.; Fliller, R.; Zheng, L.; Peggs, S.; Prigl, R.; Radeka, V. et al.
Object Type: Article
System: The UNT Digital Library
A High Precision Model of AGS Booster Tune Control (open access)

A High Precision Model of AGS Booster Tune Control

None
Date: June 2, 2002
Creator: Brown, K. A.; Fliller, R.; Meng, W. & Van Asselt, W.
Object Type: Article
System: The UNT Digital Library
Improvements of the RHIC Ramp Efficiency (open access)

Improvements of the RHIC Ramp Efficiency

The last nms in both gold-gold and polarized proton-proton required necessary corrections in the ramp as the intensities in the two rings were rising towards design values. Corrections were made with respect to the beam-beam effects, transverse and longitudinal instabilities, transition crossing (for the gold-gold ramps), transverse tune resonances, local and global coupliug problems, aperture restrictions, chromatic effects. Along the ramps we had to use the beam separation, ''Landau'' cavities, chromatic and tune control, orbit correction, special gamma-t quadrupole system for the transition crossing in the gold run, correction octupole circuits, beam position monitor system decoupling etc.
Date: June 2, 2002
Creator: Trbojevic, D.; Ptitsyn, V.; Fischer, W.; Ahrens, L.; Blaskiewicz, M.; Hayes, T. et al.
Object Type: Article
System: The UNT Digital Library
Intra - Beam Scattering Measurements in Rhic. (open access)

Intra - Beam Scattering Measurements in Rhic.

RHIC in gold operation shows significant intra-beam scattering due to the high charge state of the stored ions. Intra-beam scattering leads to longitudinal and transverse emittance growth. The longitudinal emittance growth causes debunching in operation; the transverse emittance growth contributes to the reduction of the beam and luminosity lifetimes. The longitudinal and transverse beam growth was measured. Beam growth measurement are compared with computations.
Date: June 2, 2002
Creator: Fischer, W.; Connolly, R.; Tepikian, S.; Van Zeijts, J. & Zeno, K.
Object Type: Article
System: The UNT Digital Library
Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 24, No. 123, Ed. 1 Sunday, June 2, 2002 (open access)

Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 24, No. 123, Ed. 1 Sunday, June 2, 2002

Semiweekly newspaper from Levelland, Texas that includes local, state, and national news along with advertising.
Date: June 2, 2002
Creator: Rigg, John
Object Type: Newspaper
System: The Portal to Texas History
LINEAR AND NONLINEAR CORRECTIONS IN THE RHIC INTERACTION REGIONS. (open access)

LINEAR AND NONLINEAR CORRECTIONS IN THE RHIC INTERACTION REGIONS.

A method has been developed to measure operationally the linear and non-linear effects of the interaction region triplets, that gives access to the multipole content through the action kick, by applying closed orbit bumps and analysing tune and orbit shifts. This technique has been extensively tested and used during the RHIC operations in 2001. Measurements were taken at 3 different interaction regions and for different focusing at the interaction point. Non-linear effects up to the dodecapole have been measured as well as the effects of linear, sextupolar and octupolar corrections. An analysis package for the data processing has been developed that through a precise fit of the experimental tune shift data (measured by a phase lock loop technique to better than 10{sup -5} resolution) determines the multipole content of an IR triplet.
Date: June 2, 2002
Creator: Pilat, F.; Cameron, P.; Ptitsyn, V. & Koutchouk, J. P.
Object Type: Article
System: The UNT Digital Library