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Cooling Dynamics Studies and Scenarios for the Rhic Cooler.

Description: In this paper, we discuss various electron cooling dynamics studies for RHIC. We also present simulations [1] of various possibilities of using electron cooling at RHIC, which includes cooling at the top energy, pre-cooling at low energy, aspects of transverse and longitudinal cooling and their impact on the luminosity. Electron cooling at various collision energies both for heavy ions and protons is also discussed.
Date: May 16, 2005
Creator: Fedotov, A. V.; Ben-Zvi, Ilan & Litvinenko, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tomographic Measurement of Longitudinal Emittance Growth Due to Stripping Foils.

Description: During beam acceleration in the Brookhaven accelerator complex, heavy ions are stripped of their electrons in several steps. Depending on the properties of the stripping foils, this process results in an increased energy spread and longitudinal emittance growth. A tomographic phase space reconstruction technique has been applied to measure the associated emittance growth for different stripping foil materials.
Date: May 16, 2005
Creator: Montag, C.; Ahrens, L. & Thieberger, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Circular RFQ Storage Ring.

Description: This paper presents a novel idea of storage ring for the accumulation of intense beams of light and heavy ions at low energy. The new concept is a natural development of the combined features of conventional storage rings and ion traps, and is basically a linear RFQ bent on itself. The advantages are: smaller beam dimensions, higher beam intensity, and a more compact storage device.
Date: March 29, 1999
Creator: Ruggiero, Alessandro G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of an RF-Driven Plasma Ion Source for Heavy Ion Fusion

Description: We are testing a high-current-density high-brightness Argon-Ion Source for Heavy Ion Fusion applications. The 100-kV 20-{micro}s source has produced up to 5 mA of Ar{sup +} in a single beamlet. The extraction current density is 100 mA/cm2. We have measured the emittance of the beamlet, and the fraction of Ar{sup ++} ions under several operating conditions. We present measurements of the extracted current density as a function of RF power and gas pressure ({approx} 2 mT), current density uniform… more
Date: May 13, 2003
Creator: Westenskow, G A; Hall, R P; Halaxa, E & Kwan, J W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Cross Section For Compound-Nucleus Formation In Heavy-Ion-Induced Reactions

Description: With the increasing availability of accelerators capable of producing beams of heavy ions it has become useful to know the cross section for a heavy ion to form a compound nucleus by interaction with a target nucleus. The results of calculations based on two simple models are presented here in order to give some idea of the magnitude of this cross section as a function of the energy of the bombarding particle.
Date: April 1959
Creator: Thomas, T. Darrah
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Highly-charged heavy-ion production with short pulse lasers

Description: This MathCAD document describes a possible approach using a PW -class short pulse laser to form a useful number (10{sup 12}) of high and uniform charge state ions with low ion temperature (<< 100 eV) and low momentum spread ({delta}p{sub z}/p, < 10{sup -4} ) for injection into heavy-ion fusion accelerators. As a specific example, we consider here Xenon{sup +26}, which has an ionization energy E{sub i} {approximately} 860 eV for the 26th electron, and a significantly higher ionization potential … more
Date: January 27, 1998
Creator: Logan, G.; Bitmire, T.; Perry, M.; Anderson, O. & Kuehl, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The source of elliptic flow and initial conditions for hydrodynamical calculations

Description: A model for energy, pressure and flow velocity distributions at the beginning of relativistic heavy ion collisions is presented, which can be used as initial condition for hydrodynamical calculations. The results show that QGP forms a tilted disk, such that the direction of the largest pressure gradient stays in the reaction plane, but deviates from both the beam and the usual transverse flow directions. Such initial condition may lead to the creation of antiflow or third flow component.
Date: August 2000
Creator: Strottman, D.; Csernai, L. & Magas, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design, Construction, and Application of an Electrostatic Quadrupole Doublet for Heavy Ion Nuclear Microprobe Research

Description: A nuclear microprobe, typically consisting of 2 - 4 quadrupole magnetic lenses and apertures serving as objective and a collimating divergence slits, focuses MeV ions to approximately 1 x 1 μm for modification and analysis of materials. Although far less utilized, electrostatic quadrupole fields similarly afford strong focusing of ions and have the added benefit of doing so independent of ion mass. Instead, electrostatic quadrupole focusing exhibits energy dependence on focusing ions. A heav… more
Date: December 2017
Creator: Manuel, Jack Elliot
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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RHIC and its upgrade programmes.

Description: As the first hadron accelerator and collider consisting of two independent superconducting rings RHIC has operated with a wide range of beam energies and particle species. After a brief review of the achieved performance the presentation will give an overview of the plans, challenges and status of machine upgrades, that range from a new heavy ion pre-injector and beam cooling at 100 GeV to a high luminosity electron-ion collider.
Date: June 23, 2008
Creator: Roser, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ELLIPTIC FLOW, INITIAL ECCENTRICITY AND ELLIPTIC FLOW FLUCTUATIONS IN HEAVY ION COLLISIONS AT RHIC.

Description: We present measurements of elliptic flow and event-by-event fluctuations established by the PHOBOS experiment. Elliptic flow scaled by participant eccentricity is found to be similar for both systems when collisions with the same number of participants or the same particle area density are compared. The agreement of elliptic flow between Au+Au and Cu+Cu collisions provides evidence that the matter is created in the initial stage of relativistic heavy ion collisions with transverse granularity s… more
Date: February 19, 2007
Creator: Nouicer, R.; Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M. & Barton, D. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quarkonium shadowing in pPb and Pb+Pb collisions

Description: The d+Au data from RHIC, including the pA results from the fixed-target CERN SPS pA data, suggest increased importance of initial-state shadowing and decreasing nuclear absorption with increasing energy. This is not surprising since smaller x is probed at higher energy while absorption due to multiple scattering is predicted to decrease with energy. The CERN SPS data suggest a J/{psi} absorption cross section of about 4 mb without shadowing, and a larger absorption cross section if it is includ… more
Date: May 21, 2007
Creator: Vogt, R
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tracking of Acceleration With Hnj Method.

Description: After reviewing the principle of operation of acceleration with the method of Harmonic Number Jump (HNJ) in a Fixed-Field Alternating-Gradient (FFAG) accelerator for protons and heavy ions, we report in this talk the results of computer simulations performed to assess the capability and the limits of the method in a variety of practical situations. Though the study is not yet completed, and there still remain other cases to be investigated, nonetheless the tracking results so far obtained are v… more
Date: November 5, 2007
Creator: Ruggiero, A. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exploring a unique vision for heavy ion fusion

Description: A quest for more efficient beam-to-fuel energy coupling via polar direct drive (30% overall), to enable: (1) Self-T-breeding, self-neutron-energy-absorbing, large {pi}r, T-Lean targets {at} &lt; 4 MJ driver energies; (2) Efficient fusion energy coupling into plasma for direct MHD conversion with moderate yields &lt; 1 GJ; (3) Balance-of-plant costs 10X lower than steam cycle (e.g., &lt; 80 $/kWe instead of 800 $/kWe); (4) CoE low enough (&lt;3 cts/kWehr) for affordable water and H{sub 2} fuel f… more
Date: August 6, 2007
Creator: Logan, B. G. & Logan, B. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tracking of Acceleration with HNJ Method

Description: After reviewing the principle of operation of acceleration with the method of Harmonic Number Jump (HNJ) in a Fixed-Field Alternating Gradient (FFAG) accelerator for protons and heavy ions, we report in this talk the results of computer simulations performed to assess the capability and the limits of the method in a variety of practical situations. Though the study is not yet completed, and there still remain other cases to be investigated, nonetheless the tracking results so far obtained are v… more
Date: February 1, 2008
Creator: Ruggiero, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The design of the fundamental mode damper and the HOM dampers for the 56 MHz SRF cavity

Description: A 56 MHz Superconducting RF cavity is under development for the Relativistic Heavy Ion Collider (RHIC) aiming at luminosity enhancement The 56 MHz SRF cavity can adiabatically rebucket the beam from the 28 MHz accelerating cavities, provide shorter bunches and significantly enhance the luminosity. The 56 MHz SRF cavity will be turned on at store, therefore, the fundamental mode should be damped while the beam is injected and accelerated. The feature requires a fundamental mode damper (FD). The … more
Date: May 4, 2009
Creator: Choi, E. M.; Hahn, H.; Bellavia, S. & Ben-Zvi, Ilan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High power fast ramping power supplies

Description: Hundred megawatt level fast ramping power converters to drive proton and heavy ion machines are under research and development at accelerator facilities in the world. This is a leading edge technology. There are several topologies to achieve this power level. Their advantages and related issues will be discussed.
Date: May 4, 2009
Creator: Marneris, I.; Bajon, E.; Bonati, R.; Sandberg, J.; Roser, T. & Tsoupas, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling heavy ion ionization energy loss at low and intermediate energies

Description: The needs of contemporary accelerator and space projects led to significant efforts made to include description of heavy ion interactions with matter in general-purpose Monte Carlo codes. This paper deals with an updated model of heavy ion ionization energy loss developed previously for the MARS code. The model agrees well with experimental data for various projectiles and targets including super-heavy ions in low-Z media.
Date: November 1, 2009
Creator: Rakhno, I.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On-Line Nonlinear Chromaticity Correction Using Off-Momentum Tune Response Matrix

Description: In this article, we propose a method for the online nonlinear chromaticity correction at store in the Relativistic Heavy Ion Collider (RHIC). With 8 arc sextupole families in each RHIC ring, the nonlinear chromaticities can be minimized online by matching the off-momentum tunes onto the wanted tunes given by the linear chromaticities. The Newton method is used for this multi-dimensional nonlinear optimization, where the off-momentum tune response matrix with respect to sextupole strength change… more
Date: June 25, 2007
Creator: Luo, Y.; Fischer, W.; Malisky, N.; Tepikian, S. & Trobjevic, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulations of beam-wire experiments at RHIC

Description: A weak-strong beam simulation code (BBSIM) is used to study the compensation of long range beam-beam effects by current carrying wires at the Relativistic Heavy Ion Collider. Tune footprints and tune scans of diffusive aperture are presented for various wire separation distances. Beam life time is estimated using the dependence of the transverse diffusion coefficients on initial action. Comparison of the loss rate from tracking with that measured by BNL is presented.
Date: June 1, 2007
Creator: Kim, Hyung Jin & Sen, Tanaji
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stochastic Cooling of High-Energy Bunched Beams

Description: Stochastic cooling of 100 GeV/nucleon bunched beams has been achieved in the Relativistic Heavy Ion Collider (RHIC). The physics and technology of the longitudinal cooling system are discussed, and plans for a transverse cooling system are outlined.
Date: June 25, 2007
Creator: Blaskiewicz, M. & Brennan, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Induction Linac Driver For A 0.44 MJ Heavy-Ion Direct Drive Target

Description: The conceptual design of a heavy ion fusion driver system is described, including all major components. Particular issues emerging from this exercise are identified and discussed. The most important conclusion of our study is that due to stringent requirements on ion pulse phase space, we are unable to find a credible accelerator design that meets the requirements of the example target. Either the target design must be modified to accept larger ion ranges and larger focal spot sizes, or we must… more
Date: February 8, 2010
Creator: Seidl, P.A.; Lee, E.P.; Bangerter, R.O. & Faltens, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Initial experiments of RF gas plasma source for heavy ionfusion

Description: The Source Injector Program for the US Heavy Ion Fusion Virtual National Laboratory is currently exploring the feasibility of using RF gas plasma sources for a HIF driver. This source technology is presently the leading candidate for the multiple aperture concept, in which bright millimeter size beamlets are extracted and accelerated electrostatically up to 1 MeV before the beamlets are allowed to merge and form 1 A beams. Initial experiments have successfully demonstrated simultaneously high c… more
Date: May 22, 2002
Creator: Ahle, L.; Hall, R.; Molvik, A. W.; Chacon-Golcher, E.; Kwan, J. W.; Leung, K. N. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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