Setup and Performance of the Rhic Injector Accelerators for the 2007 Run With Gold Ions (open access)

Setup and Performance of the Rhic Injector Accelerators for the 2007 Run With Gold Ions

Gold ions for the 2007 run of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) are accelerated in the Tandem, Booster and AGS prior to injection into RHIC. The setup and performance of this chain of accelerators is reviewed with a focus on improvements in the quality of beam delivered to RHIC. In particular, more uniform stripping foils between Booster and AGS7 and a new bunch merging scheme in AGS have provided beam bunches with reduced longitudinal emittance for RHIC.
Date: June 25, 2007
Creator: Gardner, C.; Ahrens, L.; Alessi, J.; Benjamin, J.; Blaskiewicz, M. & Al., Et
Object Type: Article
System: The UNT Digital Library
Uniform Beam Distributions at the Target of the NSRL Beam Transfer Line (open access)

Uniform Beam Distributions at the Target of the NSRL Beam Transfer Line

Uniform irradiation of biological or material samples with charged particle beams is desired by experimenters because it reduces radiation dose errors. In this paper we present results of uniform beams produced in the NASA SPACE RADIATION LABORATORY (NSRL) at the Brookhaven National Laboratory (BNL) by a method which was developed theoretically and was proven experimentally at BNL. A similar method which requires collimation of the beam, and also lacks the flexibility of the present method to produce beam various beam sizes at the target, was patented in the year 1988. The present method of producing uniform beam distributions on a plane transverse to the direction of the beam, is based on purely magnetic focusing of the beam and requires no collimation of the beam or any other type of beam interaction with materials. It can also generate uniform beam distributions of various sizes. The method is favorably compared with alternative methods of producing uniform beam distributions and can be applied to the whole energy spectrum of the charged particle beams that are delivered by the BNL Booster synchrotron.
Date: June 25, 2007
Creator: Tsoupas, N.; Ahrens, L.; Brown, K. Chiang, I-Hung, Gardner, C. J.; MacKay, W. W.; Pile, P. & Rusek, A.
Object Type: Article
System: The UNT Digital Library
Overcoming Depolarizing Resonances in the AGS With Two Helical Partial Snakes (open access)

Overcoming Depolarizing Resonances in the AGS With Two Helical Partial Snakes

Dual partial snake scheme has provided polarized proton beams with 1.5 x 10{sup 11} intensity and 65% polarization for the Relativistic Heavy Ion Collider (RHIC) spin program. To overcome the residual polarization loss due to horizontal resonances in the Brookhaven Alternating Gradient Synchrotron (AGS), a new string of quadrupoles have been added. The horizontal tune can then be set in the spin tune gap generated by the two partial snakes, such that horizontal resonances can also be avoided. This paper presents the accelerator setup and preliminary results.
Date: June 25, 2007
Creator: Huang, H.; Ahrens, L.; Bai, M.; Brown, K. A.; Gardner, C. J.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Accelerating Polarized Protons to 250 GEV (open access)

Accelerating Polarized Protons to 250 GEV

The Relativistic Heavy Ion Collider (RHIC) as the first high energy polarized proton collider was designed t o provide polarized proton collisions a t a maximum beam energy of 250 GeV. I t has been providing collisions a t a beam energy of 100 Gel' since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during the acceleration from injection to 100 GeV with careful control of the betatron tunes and the vertical orbit distortions. However, the intrinsic spin resonances beyond 100 GeV are about a factor of two stronger than those below 100 GeV? making it important t o examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were accelerated t o the record energy of 250 GeV in RHIC with a polarization of 46% measured a t top energy in 2006. The polarization measurement as a function of beam energy also shows some polarization loss around 136 GeV, the first strong intrinsic resonance above 100 GeV. This paper presents the results and discusses the sensitivity of the polarization survival t o orbit distortions.
Date: June 25, 2007
Creator: Bai, M.; Ahrens, L.; Alekseev, I. G.; Alessi, J.; Beebe-Wang, J. & AL., ET
Object Type: Article
System: The UNT Digital Library
A Survey of Hadron Therapy Accelerator Technologies. (open access)

A Survey of Hadron Therapy Accelerator Technologies.

Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy.
Date: June 25, 2007
Creator: Peggs, S.; Satogata, T. & Flanz, J.
Object Type: Article
System: The UNT Digital Library
Sensitivity analysis for joint inversion of ground-penetratingradar and thermal-hydrological data from a large-scale underground heatertest (open access)

Sensitivity analysis for joint inversion of ground-penetratingradar and thermal-hydrological data from a large-scale underground heatertest

We describe a joint inversion approach that combinesgeophysical and thermal-hydrological data for the estimation of (1)thermal-hydrological parameters (such as permeability, porosity, thermalconductivity, and parameters of the capillary pressure and relativepermeability functions) that are necessary for predicting the flow offluids and heat in fractured porous media, and (2) parameters of thepetrophysical function that relates water saturation, porosity andtemperature to the dielectric constant. The approach incorporates thecoupled simulation of nonisothermal multiphase fluid flow andground-penetrating radar (GPR) travel times within an optimizationframework. We discuss application of the approach to a large-scale insitu heater test which was conducted at Yucca Mountain, Nevada, to betterunderstand the coupled thermal, hydrological, mechanical, and chemicalprocesses that may occur in the fractured rock mass around a geologicrepository for high-level radioactive waste. We provide a description ofthe time-lapse geophysical data (i.e., cross-borehole ground-penetratingradar) and thermal-hydrological data (i.e., temperature and water contentdata) collected before and during the four-year heating phase of thetest, and analyze the sensitivity of the most relevantthermal-hydrological and petrophysical parameters to the available data.To demonstrate feasibility of the approach, and as a first step towardcomprehensive inversion of the heater test data, we apply the approach toestimate one parameter, the permeability of the rock matrix.
Date: June 25, 2007
Creator: Kowalsky, M. B.; Birkholzer, J.; Peterson, J.; Finsterle, S.; Mukhopadhya, Y. S. & Tsang, Y. T.
Object Type: Article
System: The UNT Digital Library
Development of Radar Navigation and Radio Data Transmission for Microhole Coiled Tubing Bottom Hole Assemblies (open access)

Development of Radar Navigation and Radio Data Transmission for Microhole Coiled Tubing Bottom Hole Assemblies

This Final Technical Report summarizes the research and development (R&D) work performed by Stolar Research Corporation (Stolar) under U.S. Department of Energy (DOE) Contract Number DE-FC26-04NT15477. This work involved the development of radar navigation and radio data transmission systems for integration with microhole coiled tubing bottom hole assemblies. Under this contract, Stolar designed, fabricated, and laboratory and field tested two advanced technologies of importance to the future growth of the U.S. oil and gas industry: (1) real-time measurement-while-drilling (MWD) for guidance and navigation of coiled tubing drilling in hydrocarbon reservoirs and (2) two-way inductive radio data transmission on coiled tubing for real-time, subsurface-to-surface data transmission. The operating specifications for these technologies are compatible with 3.5-inch boreholes drilled to a true vertical depth (TVD) of 5,000 feet, which is typical of coiled tubing drilling applications. These two technologies (i.e., the Stolar Data Transmission System and Drill String Radar) were developed into pre-commercial prototypes and tested successfully in simulated coiled tubing drilling conditions. Integration of these two technologies provides a real-time geosteering capability with extremely quick response times. Stolar is conducting additional work required to transition the Drill String Radar into a true commercial product. The results of this advanced development work …
Date: March 25, 2007
Creator: Stolarczyk, Larry G.; Stolarczyk, Gerald L.; Icerman, Larry; Howard, John & Tehrani, Hooman
Object Type: Report
System: The UNT Digital Library