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1

Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Relativistic Heavy Ion Collider Relativistic Heavy Ion Collider managed for the U.S. Department of Energy by Brookhaven Science Associates, founded by Stony Brook University and Battelle. managed for the U.S. Department of Energy by Brookhaven Science Associates, a company founded by Stony Brook University and Battelle 07/07 Brookhaven National Laboratory Funded by the U.S. Department of Energy, Brookhaven National Laboratory is a multipurpose research institution located on a 5,300-acre site on Long Island, New York. Six Nobel Prize-winning discoveries have been made at Brookhaven Lab. The Laboratory operates large-scale scientific facilities and performs research in physics, chemistry, biology, medicine, applied science, and

2

Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

at the same time. Capable of accelerating 70 trillion protons with every pulse, and heavy ions such as gold and iron, the AGS receives protons and other ions from the AGS...

3

RHIC | Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

indicate that collisions of small particles with large gold nuclei at the Relativistic Heavy Ion Collider may be serving up miniscule servings of hot quark-gluon plasma. RHIC...

4

Relativistic Heavy Ion Collider, RHIC  

NLE Websites -- All DOE Office Websites (Extended Search)

The Relativistic Heavy Ion Collider website has moved to www.bnl.govrhicdefault.asp Sponsored by the U.S. Department of Energy Office of Science, Office of Nuclear Physics. Last...

5

RHIC | Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Relativistic Heavy Ion Collider Relativistic Heavy Ion Collider Photo of LINAC The Relativistic Heavy Ion Collider (RHIC) is a world-class particle accelerator at Brookhaven National Laboratory where physicists are exploring the most fundamental forces and properties of matter and the early universe. RHIC accelerates beams of particles (e.g., the nuclei of heavy atoms such as gold) to nearly the speed of light, and smashes them together to recreate a state of matter thought to have existed immediately after the Big Bang some 13.8 billion years ago. STAR and PHENIX, two large detectors located around the 2.4-mile-circumference accelerator, take "snapshots" of these collisions to reveal a glimpse of the basic constituents of visible matter, quarks and gluons. Understanding matter at

6

RHIC | Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites

Brookhaven National Laboratory Brookhaven National Laboratory search U.S. Department of Energy logo Home RHIC Science News Images Videos For Scientists Björn Schenke 490th Brookhaven Lecture, 12/18 Join Björn Schenke of Brookhaven Lab's Physics Department for the 490th Brookhaven Lecture, titled 'The Shape and Flow of Heavy Ion Collisions,' on Wednesday, Dec. 18, at 4 p.m. in Berkner Hall. droplets Tiny Drops of Hot Quark Soup-How Small Can They Be? New analyses indicate that collisions of small particles with large gold nuclei at the Relativistic Heavy Ion Collider may be serving up miniscule servings of hot quark-gluon plasma. RHIC Physics RHIC is the first machine in the world capable of colliding ions as heavy as gold. The Spin Puzzle RHIC is the world's only machine capable of colliding beams of polarized

7

RHIC | Physics of the Relativistic Heavy Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

The Physics of RHIC Physicists from around the world are using the Relativistic Heavy Ion Collider to explore some of Nature's most basic -- and intriguing -- ingredients and...

8

Brookhaven National Laboratory The Relativistic Heavy Ion Collider (RHIC)  

NLE Websites -- All DOE Office Websites (Extended Search)

Relativistic Heavy Ion Collider (RHIC) Relativistic Heavy Ion Collider (RHIC) An Exciting Beginning and a Compelling Future At the Relativistic Heavy Ion Collider (RHIC), a world-class particle accelerator at Brookhaven National Laboratory, physicists are exploring the most fundamental forces and properties of matter and the early universe, with important implications for our understanding of the world around us. Operated with funding from the U.S. Department of Energy's Office of Science, the Relativistic Heavy Ion Collider (RHIC), was designed to recreate a state of matter thought to have existed immediately after the Big Bang some 13 billion years ago, and to investigate how the proton gets its spin and intrinsic magnetism from its quark and gluon constituents. Large detectors located

9

Relativistic Heavy Ion Collider | The Case for Continuing Operations  

NLE Websites -- All DOE Office Websites (Extended Search)

The Case for Continuing RHIC Operations The Case for Continuing RHIC Operations The Relativistic Heavy Ion Collider (RHIC) - the nation's only remaining particle collider, located at Brookhaven National Laboratory - has made a series of landmark discoveries and continuing breakthroughs in science and technology. One major accomplishment has been RHIC's ability to recreate and study in detail a type of matter that last existed at the beginning of the universe to better understand the strongest force in nature - the force that holds together the fundamental particles that make up 99 percent of visible matter in the universe today, everything from stars to planets to people. In addition to giving us a new way to explore and understand the nature of the early universe and the force that holds together ordinary matter, research at RHIC has revealed stunning

10

Observation of snake resonances at Relativistic Heavy Ion Collider  

SciTech Connect

The Siberian snakes are powerful tools in preserving polarization in high energy accelerators has been demonstrated at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the Siberian snakes also introduce a new set of depolarization resonances, i.e. snake resonances as first discovered by Lee and Tepikian. The intrinsic spin resonances above 100 GeV are about a factor of two stronger than those below 100 GeV which raises the challenge to preserve the polarization up to 250 GeV. In 2009, polarized protons collided for the first time at the RHIC design store energy of 250 GeV. This paper presents the experimental measurements of snake resonances at RHIC. The plan for avoiding these resonances is also presented.

Bai, M.; Ahrens, L.; Alekseev, I.G.; Alessi, J.; et al

2010-09-27T23:59:59.000Z

11

Relativistic Heavy Ion Collider (RHIC) Animation and Multimedia Collection  

DOE Data Explorer (OSTI)

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is a world-class scientific research facility that began operation in 2000, following 10 years of development and onstruction. Hundreds of physicists from around the world use RHIC to study what the universe may have looked like in the first few moments after its creation. RHIC drives two intersecting beams of gold ions head-on, in a subatomic collision. This library of animations and multimedia includes virtual video tours of the RHIC complex, of the spin configuration, and of experiments; documentaries of the science involved; animations of the various kinds of collisions and reactions; event displays; and even interactive Java games about RHIC and RHIC physics.

12

Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider  

E-Print Network (OSTI)

We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon Au beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future Pb beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

R. Bruce; M. Blaskiewicz; W. Fischer; J. M. Jowett

2010-09-08T23:59:59.000Z

13

RHIC | Electron-Ion Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron-Ion Collider A breakthrough particle accelerator could collide electrons with heavy ions or protons at nearly the speed of light to create rapid-fire, high-resolution...

14

The Relativistic Heavy Ion Collider (RHIC) - the nation's only remaining  

NLE Websites -- All DOE Office Websites (Extended Search)

Collider (RHIC) - the nation's only remaining Collider (RHIC) - the nation's only remaining particle collider, located at Brookhaven National Laboratory - has made a series of landmark discoveries and continuing breakthroughs in science and technology. One major accomplishment has been RHIC's ability to recreate and study in detail a type of matter that last existed at the beginning of the universe to better understand the strongest force in nature - the force that holds together the fundamental particles that make up 99 percent of visible matter in the universe today, everything from stars to planets to people. In addition to giving us a new way to explore and understand the nature of the early universe and the force that holds together ordinary matter, research at RHIC has revealed stunning

15

The Multi-Purpose Detector for NICA heavy-Ion Collider at JINR  

Science Conference Proceedings (OSTI)

The Multi-Purpose Detector (MPD) is designed to study heavy-ion collisions at the Nuclotron-based heavy Ion Collider fAcility (NICA) at JINR, Dubna. Its main components located inside a superconducting solenoid are a tracking system composed of a silicon microstrip vertex detector followed by a large volume time-projection chamber, a time-of-flight system for particle identification and a barrel electromagnetic calorimeter. A zero degree hadron calorimeter is designed specifically to measure the energy of spectators. In this paper, all parts of the apparatus are described and their tracking and particle identification parameters are discussed in some detail.

Rogachevsky, O. V., E-mail: rogachevsky@jinr.ru [JINR, Veksler and Baldin Laboratory on High Energy Physics (Russian Federation)

2012-05-15T23:59:59.000Z

16

Proton Polarimetry at the Relativistic Heavy Ion Collider  

DOE Green Energy (OSTI)

The RHIC polarized proton collider employs polarimeters in each of the Blue and Yellow rings that utilize the analyzing power in p-Carbon elastic scattering in the Coulomb Nuclear Interference region to measure the absolute beam polarization. These are calibrated by the polarized Hydrogen Jet Target that measures the absolute beam polarization in pp elastic scattering in the CNI region. This paper describes the status and performance of these polarimeters in the FY09 run which included both a 250 GeV/c and 100 GeV/c physics data taking periods. We will describe some of the difficulties encountered and the efforts underway to improve the performance in better energy resolution, rate handling capability, and reduced systematic uncertainties.

Makdisi, Y.; Aschenauer, E.; Atoian, G.; Bazilevsky, A.; Bunce, G.; Gill, R.; Huang, H.; Morozov, B.; Rescia, S.; Sivertz, M.; Yip, K.; Zelenski, A.; Lee, S.K.; Li, X.; Alekseev, I.; Svirida, D.

2009-09-07T23:59:59.000Z

17

PROCEEDINGS OF THE SECOND WORKSHOP ON EXPERIMENTS AND DETECTORS FOR A RELATIVISTIC HEAVY ION COLLIDER (RHIC), LAWRENCE BERKELEY LABORATORY, MAY 25-29, 1987  

E-Print Network (OSTI)

Heavy-Ion Collider. Brookhaven National Lab.. Upton N.Y. (Zingman Lawrence Berkeley Laboratory Brookhaven NationalLaboratory Brookhaven National Laboratory Johns Hopkins

Ritter, Hans Georg

2010-01-01T23:59:59.000Z

18

Vector meson production in coherent hadronic interactions: Update on predictions for energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider  

SciTech Connect

In this Rapid Communication we update our predictions for the photoproduction of vector mesons in coherent pp and AA collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies using the color dipole approach and the Color Glass Condensate formalism. In particular, we present our predictions for the first run of the LHC at half energy and for the rapidity dependence of the ratio between the J/{Psi} and {rho} cross sections at RHIC energies.

Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas Caixa Postal 354, CEP 96010-900, Pelotas, RS (Brazil); Machado, M. V. T. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil)

2011-07-15T23:59:59.000Z

19

Bound-free pair production cross section in heavy-ion colliders from the equivalent photon approach  

E-Print Network (OSTI)

Exact calculations of the electron-positron pair production by a single photon in the Coulomb field of a nucleus with simultaneous capture of the electron into the K-shell are discussed for different nuclear charges. Using the equivalent photon method of Weizsaecker and Williams, a simple expression for the bound-free production of electron-positron pairs by colliding very-high-energy fully stripped heavy ions is derived for nuclei of arbitrary charge.

Andreas Aste

2007-10-23T23:59:59.000Z

20

PREVENTING POLLUTION USING ISO 14001 AT A PARTICLE ACCELERATOR THE RELATIVISTIC HEAVY ION COLLIDER PROJECT.  

SciTech Connect

In early 1997 Brookhaven National Laboratory (BNL) discovered that the spent fuel pool of their High Flux Beam Reactor was leaking tritium into the groundwater. Community members, activist groups, politicians and regulators were outraged with the poor environmental management practices at BNL. The reactor was shut down and the Department of Energy (DOE) terminated the contract with the existing Management Company. At this same time, a major new scientific facility, the Relativistic Heavy Ion Collider (RHIC), was nearing the end of construction and readying for commissioning. Although environmental considerations had been incorporated into the design of the facility; some interested parties were skeptical that this new facility would not cause significant environmental impacts. RHIC management recognized that the future of its operation was dependent on preventing pollution and allaying concerns of its stakeholders. Although never done at a DOE National Laboratory before Brookhaven Science Associates, the new management firm, committed to implementing an Environmental Management System (EMS) and RHIC managers volunteered to deploy it within their facility on an extremely aggressive schedule. Several of these IS0 requirements contribute directly to preventing pollution, an area where particular emphasis was placed. This paper describes how Brookhaven used the following key IS0 14001 elements to institutionalize Pollution Prevention concepts: Environmental Policy, Aspects, Objectives and Targets, Environmental Management Program, Structure and Responsibility, Operational Controls, Training, and Management Review. In addition, examples of implementation at the RHIC Project illustrate how BNL's premiere facility was able to demonstrate to interested parties that care had been taken to implement technological and administrative controls to minimize environmental impacts, while at the same time reduce the applicability of regulatory requirements to their operations.

BRIGGS,S.L.K.; MUSOLINO,S.V.

2001-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Strange quark suppression and strange hadron production in pp collisions at energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider  

Science Conference Proceedings (OSTI)

The parton and hadron cascade model PACIAE based on PYTHIA is utilized to systematically investigate strange particle production in pp collisions at energies available at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC). Globally speaking, the PACIAE results of the strange particle rapidity density at midrapidity and the transverse momentum distribution are better than those of PYTHIA (default) in comparison with STAR and ALICE experimental data. This may represent the importance of the parton and hadron rescatterings, as well as the reduction mechanism of strange quark suppression, added in the PACIAE model. The K/{pi} ratios as a function of reaction energy in pp collisions from CERN Super Proton Synchrotron (SPS) to LHC energies are also analyzed in this paper.

Long Haiyan; Feng Shengqin; Zhou Daimei; Yan Yuliang; Ma Hailiang; Sa Benhao [Department of Physics, College of Science, China Three Gorges University, Yichang 443002 (China); Institute of Particle Physics, Huazhong Normal University, Wuhan 430082 (China); China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Institute of Particle Physics, Huazhong Normal University, Wuhan 430082 (China); CCAST (World Laboratory), P.O. Box 8730, Beijing 100080 (China)

2011-09-15T23:59:59.000Z

22

Sorting chromatic sextupoles for easily and effectively correcting second order chromaticity in the Relativistic Heavy Ion Collider  

Science Conference Proceedings (OSTI)

Based on the contributions of the chromatic sextupole families to the half-integer resonance driving terms, we discuss how to sort the chromatic sextupoles in the arcs of the Relativistic Heavy Ion Collider (RHIC) to easily and effectively correct the second order chromaticities. We propose a method with 4 knobs corresponding to 4 pairs of chromatic sextupole families to online correct the second order chromaticities. Numerical simulation justifies this method, showing that this method reduces the unbalance in the correction strengths of sextupole families and avoids the reversal of sextupole polarities. Therefore, this method yields larger dynamic apertures for the proposed RHIC 2009 100GeV polarized proton run lattices.

Luo,Y.; Tepikian, S.; Fischer, W.; Robert-Demolaize, G.; Trbojevic, D.

2009-01-02T23:59:59.000Z

23

Fourth workshop on experiments and detectors for a relativistic heavy ion collider  

Science Conference Proceedings (OSTI)

This report contains papers on the following topics: physics at RHIC; flavor flow from quark-gluon plasma; space-time quark-gluon cascade; jets in relativistic heavy ion collisions; parton distributions in hard nuclear collisions; experimental working groups, two-arm electron/photon spectrometer collaboration; total and elastic pp cross sections; a 4{pi} tracking TPC magnetic spectrometer; hadron spectroscopy; efficiency and background simulations for J/{psi} detection in the RHIC dimuon experiment; the collision regions beam crossing geometries; Monte Carlo simulations of interactions and detectors; proton-nucleus interactions; the physics of strong electromagnetic fields in collisions of relativistic heavy ions; a real time expert system for experimental high energy/nuclear physics; the development of silicon multiplicity detectors; a pad readout detector for CRID/tracking; RHIC TPC R D progress and goals; development of analog memories for RHIC detector front-end electronic systems; calorimeter/absorber optimization for a RHIC dimuon experiment; construction of a highly segmented high resolution TOF system; progress report on a fast, particle-identifying trigger based on ring-imaging and highly integrated electronics for a TPC detector.

Fatyga, M.; Moskowitz, B. (eds.)

1990-01-01T23:59:59.000Z

24

Heavy-quark probes of the quark-gluon plasma and interpretation of recent data taken at the BNL Relativistic Heavy Ion Collider  

E-Print Network (OSTI)

Thermalization and collective flow of charm (c) and bottom (b) quarks in ultrarelativistic heavy-ion collisions are evaluated based on elastic parton rescattering in an expanding quark-gluon plasma (QGP). We show that resonant interactions in a strongly interacting QGP (sQGP), as well as parton coalescence, can play an essential role in the interpretation of recent data from the BNL Relativistic Heavy-Ion Collider (RHIC), and thus illuminate the nature of the sQGP and its hadronization. Our main assumption, motivated by recent findings in lattice quantum chromodynamics, is the existence of D- and B-meson states in the sQGP, providing resonant cross sections for heavy quarks. Pertinent drag and diffusion coefficients are implemented into a relativistic Langevin simulation to compute transverse-momentum spectra and azimuthal asymmetries (v(2)) of b- and c-quarks in Au-Au collisions at RHIC. After hadronization into D- and B-mesons using quark coalescence and fragmentation, associated electron-decay spectra and v(2) are compared to recent RHIC data. Our results suggest a reevaluation of radiative and elastic quark energy-loss mechanisms in the sQGP.

van Hees, H.; Greco, V.; Rapp, Ralf.

2006-01-01T23:59:59.000Z

25

System-size independence of directed flow at the Relativistic Heavy-Ion Collider  

E-Print Network (OSTI)

We measure directed flow ($v_1$) for charged particles in Au+Au and Cu+Cu collisions at $\\sqrt{s_{NN}} =$ 200 GeV and 62.4 GeV, as a function of pseudorapidity ($\\eta$), transverse momentum ($p_t$) and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all existing models, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to different collision systems, and investigate possible explanations for the observed sign change in $v_1(p_t)$.

STAR Collaboration; B. I. Abelev

2008-07-09T23:59:59.000Z

26

Heavy Ion Collisions at RHIC  

NLE Websites -- All DOE Office Websites (Extended Search)

at Heavy Ion Colliders at Heavy Ion Colliders Theory Drivers & View from LHC Urs Achim Wiedemann CERN PH-TH NSAC Implementation Subcommittee Hearings 7 September 2012 Heavy Ion Physics - Main Tools of Theorists Understanding properties of hot and dense matter from the elementary interactions in QCD High Energy Physics String Theory Computational Physics Fluid Dynamics Dissipative fluid dynamic description * Based on: E-p conservation: 2 nd law of thermodynamics: * Sensitive to properties of matter that are calculated from first principles in quantum field theory - EOS: and sound velocity - transport coefficients: shear , bulk viscosity, conductivities ...

27

Heavy-Ion Physics with CMS  

E-Print Network (OSTI)

This article presents a brief overview of the CMS experiment capabilities to study the hot and dense matter created in relativistic heavy-ion collisions. The CERN Large Hadron Collider will provide collisions of Pb nuclei at 5.5 TeV per nucleon. The CMS heavy ion group has developed a plethora of physics analyses addressing many important aspects of heavy-ion physics in preparation for a competitive and successful program.

Aneta Iordanova

2008-06-06T23:59:59.000Z

28

THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) REFRIGERATOR SYSTEM AT BROOKHAVEN NATIONAL LABORATORY: PHASE III OF THE SYSTEM PERFORMANCE AND OPERATIONS UPGRADES FOR 2003  

SciTech Connect

An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and I1 of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase 111, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for, the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.

SIDI-YEKHLEF,A.; TUOZZOLO,J.; THAN, R.; KNUDSEN, P.; ARENIUS, D.

2005-08-29T23:59:59.000Z

29

Ion polarization in the MEIC figure-8 ion collider ring  

SciTech Connect

The nuclear physics program envisaged at the Medium-energy Electron-Ion Collider (MEIC) currently being developed at the Jefferson Lab calls for collisions of 3-11 GeV/c longitudinally polarized electrons and 20-100 GeV/c, in equivalent proton momentum, longitudinally/ transversely polarized protons/ deuterons/ light ions. We present a scheme that provides the required ion polarization arrangement in the MEIC's ion collider ring.

V.S. Morozov, Ya.S. Derbenev, Y. Zhang, P. Chevtsov, A.M. Kondratenko, M.A. Kondratenko, Yu.N. Filatov

2012-07-01T23:59:59.000Z

30

HEAVY ION INERTIAL FUSION  

E-Print Network (OSTI)

Accelerators as Drivers for Inertially Confined Fusion, W.B.LBL-9332/SLAC-22l (1979) Fusion Driven by Heavy Ion Beams,OF CALIFORNIA f Accelerator & Fusion Research Division

Keefe, D.

2008-01-01T23:59:59.000Z

31

AdS/CFT Correspondence and Hydrodynamics of Relativistic Heavy Ion Collisions.  

E-Print Network (OSTI)

??The experiments performed at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab have discovered a state of matter called the strongly coupled quark-gluon (more)

Alsup, James Ethan

2010-01-01T23:59:59.000Z

32

Heavy ion fusion--Using heavy ions to make electricity  

E-Print Network (OSTI)

in Proc. of the Inertial Fusion Science and ApplicationsP. Abbott, P. F. Peterson, Fusion Science and Technology 44March 1520, 2004 Heavy Ion Fusion Using Heavy Ions to Make

Celata, C.M.

2004-01-01T23:59:59.000Z

33

Solenoid transport for heavy ion fusion  

E-Print Network (OSTI)

Transport for Heavy Ion Fusion* Edward Lee** LawrenceHm Heavy Ion Inertial Fusion Abstract Solenoid transport ofseveral stages of a heavy ion fusion driver. In general this

Lee, Edward

2004-01-01T23:59:59.000Z

34

Heavy flavor production and top quark search at hadron colliders  

SciTech Connect

We review heavy flavor production at hadron colliders, with an eye towards the physics of the top quark. Motivation for existence of top, and current status of top search are reviewed. The physics of event simulation at hadron colliders is reviewed. We discuss characteristics of top quark events at p{bar p} colliders that may aid in distinguishing the top quark signal from Standard Model backgrounds, and illustrate various cuts which may be useful for top discovery. Top physics at hadron supercolliders is commented upon, as well as top quark mass measurement techniques. 22 refs., 5 figs.

Baer, H.A.

1991-01-01T23:59:59.000Z

35

HEAVY ION LINEAR ACCELERATOR  

DOE Patents (OSTI)

A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

Van Atta, C.M.; Beringer, R.; Smith, L.

1959-01-01T23:59:59.000Z

36

Detecting exotic heavy leptons at the large hadron collider.  

E-Print Network (OSTI)

ar X iv :h ep -p h/ 01 08 09 7v 1 1 0 A ug 2 00 1 Preprint typeset in JHEP style. - HYPER VERSION Cavendish-HEP-01/10 DAMTP-2001-71 CERN-TH/2001-205 Detecting Exotic Heavy Leptons at the Large Hadron Collider B.C. Allanach?, C.M. Harris, M... , CB3 0WA, UK. Abstract: New almost-degenerate charged and neutral heavy leptons are a feature of a number of theories of physics beyond the Standard Model. The prospects for detecting these at the Large Hadron Collider using a time-of-flight technique...

Allanach, B C; Harris, Chris M; Parker, Michael A; Richardson, P; Webber, Bryan R

37

Heavy Ions - Cyclotron  

NLE Websites -- All DOE Office Websites (Extended Search)

Heavy Ions Heavy Ions Heavy ions used at the BASE Facility are accelerated in the form of "cocktails," named because of the fact that several heavy ions with the same mass-to-charge ratio are sent into the Cyclotron, which accelerates the ions while acting as a precision mass separator. The Control Room Operator then uses Cyclotron frequency to select only the desired ion, a process that takes about 2 minutes. We provide four standard cocktails: 4.5, 10, 16, and 30 MeV/nucleon. Depending on the cocktail, LETs from 1 to 100 MeV/(mg/cm^2) and flux levels of up to 1E7 ions/cm2-sec are available. Parts are tested in our vacuum chamber, and can be remotely positioned horizontally, vertically, or rotationally (y and z axes) with the motion table. An alignment laser is available to ensure the part is in the center of the beam. Mounting hardware is readily available. 12xBNC (F-F), 2x25-pin D (F-M or M-F), 4x40-pin flat ribbon (M-M), 4x50-pin flat ribbon (M-M), 12xSMA (F-F), and 2xEthernet vacuum feedthroughs are mounted upon request. (The 4x40-pin and 4x50-pin flat ribbon connectors are wired straight across, so you will need a F-F adapter to correct the pin numbers to normal.) Holes are provided through the cave shielding blocks for connecting additional test equipment, with a distance of approximately 10 feet from vacuum feedthrough to the top of the shielding block.

38

Electron Ion Collider: The Next QCD Frontier  

NLE Websites -- All DOE Office Websites (Extended Search)

Ion Collider: Ion Collider: The Next QCD Frontier Understanding the glue that binds us all Electron Ion Collider: The Next QCD Frontier Understanding the glue that binds us all BNL-98815-2012-JA JLAB-PHY-12-1652 arXiv:1212.1701 Authors A. Accardi 14,28 , J. L. Albacete 16 , M. Anselmino 29 , N. Armesto 36 , E. C. Aschenauer 3,† , A. Bacchetta 35 , D. Boer 33 , W. Brooks 37,† , T. Burton 3 , N.-B. Chang 23 , W.-T. Deng 13,23 , A. Deshpande 25,∗,† , M. Diehl 11,† , A. Dumitru 2 , R. Dupr´ e 7 , R. Ent 28,‡ , S. Fazio 3 , H. Gao 12,† , V. Guzey 28 , H. Hakobyan 37 , Y. Hao 3 , D. Hasch 15 , R. Holt 1,† , T. Horn 5,† , M. Huang 23 , A. Hutton 28,† , C. Hyde 20 , J. Jalilian-Marian 2 , S. Klein 17 , B. Kopeliovich 37 , Y. Kovchegov 19,† , K. Kumar 24,† , K. Kumeriˇ cki 40 , M. A. C. Lamont 3 , T. Lappi 34 , J.-H. Lee 3 , Y. Lee 3 , E. M. Levin 26,37 , F.-L. Lin 28 , V. Litvinenko 3 , T. W. Ludlam 3,‡ , C. Marquet

39

Characterizing Heavy Ion  

NLE Websites -- All DOE Office Websites (Extended Search)

Heavy Ion Heavy Ion Reactions in the 1980's Is there Treasure at the end of the Rainbow? & What happens and how do different modes compete? John Schiffer One of the three research areas for ATLAS, as stated in a 1984 document to Congress: Are there some new marvelous symmetries, hidden in resonances in heavier nuclei, beyond 12 C+ 12 C and its immediate vicinity? (s.c. linac work, pre-ATLAS) Other attempts to chase the rainbow 180 o elastic scattering of 12 C on 40 Ca shows structure Fusion of 16 O on 40 Ca does not. In the end, it seemed that these structures were sometimes present in alpha-particle nuclei, but almost never in others. Some optimists, continued the pursuit. We also looked at the total fusion cross section in systems that showed resonances in scattering.

40

DEDICATED HEAVY ION MEDICAL ACCELERATORS  

E-Print Network (OSTI)

et al. , ,8iological and Medical Research with Acceleratedet al. , "Biological and Medical Research with J\\cceleratedic Heavy Ions in Medical and Scientific Research, Edmonton,

Gough, R.A.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Heavy Ion Fusion development plan  

SciTech Connect

Some general cnsiderations in the fusion development program are given. The various factors are considered that must be determined before heavy ion fusion can be assessed. (MOW)

Maschke, A.W.

1978-01-01T23:59:59.000Z

42

Very high energy heavy-ion accelerators  

SciTech Connect

A review is given of various programs for building heavy ion accelerators. Topics discussed are (1) options of reaching very high energies with heavy ions; (2) present performance of the superHILAC and the Bevalac; (3) heavy ion sources; (4) applications of heavy ion accelerators outside of basic research; and (5) reliability and operating costs of heavy ion sources. (PMA)

Grunder, H.A.

1975-10-01T23:59:59.000Z

43

SYNCHROTRONS FOR HEAVY IONS - BEVALAC EXPERIENCE  

E-Print Network (OSTI)

Heavy Ions ir. Medical and Scientific Research", Edmonton,Heavy Ions in Medical and Scientific Research" Edmonton,vigorous medical and nuclear science research groups. The

Grunder, H.A.

2010-01-01T23:59:59.000Z

44

Charged heavy vector boson production at the Large Hadron Collider  

E-Print Network (OSTI)

We evaluate the sensitivity of the Large Hadron Collider (LHC) to charged heavy vector boson production followed by their decays to $W^\\pm Z^0$. We include the correlated decays of the gauge bosons to leptonic final states. With an integrated luminosity of $10^5$ pb$^{-1}$, charged technirhos in the minimal SU(N)$_{TC}$ model for $N\\geq 7$ yield signals with a significance larger than 5. In more general models, we explore the range of parameter space to which LHC experiments will be sensitive. Rapidity correlations exhibiting enhanced longitudinal gauge boson pair production are also shown.

Dal Soo Oh; M. H. Reno

1998-12-02T23:59:59.000Z

45

Heavy ion fusion--Using heavy ions to make electricity  

E-Print Network (OSTI)

for a practical fusion power reactor. HIF is the only fusionenter the reactor chamber, and focus Heavy Ion Fusion ontoengineering test reactor. The promise of fusion as a power

Celata, C.M.

2004-01-01T23:59:59.000Z

46

Relativistic Heavy Ion Collider Funding Agencies  

NLE Websites -- All DOE Office Websites (Extended Search)

Funding Agencies Funding Agencies In addition to the operations funding received from the Office of Nuclear Physics within the U.S. Department of Energy's Office of Science, RHIC experiments receive funding from a variety of sources PHENIX U.S. National Science Foundation Ministry of Education, Culture, Sports, Science and Technology of Japan Japan Society for the Promotion of Science National Council for Scientific and Technological Development, Brazil Research Supporting Foundation of the State of Sao Paulo, Brazil National Natural Science Foundation of China National Institute of Nuclear Physics and Particle Physics of the National Center for Scientific Research of France Atomic Energy Commission of France ARMINES (France) Federal Ministry of Education and Research of Germany

47

Accelerators for heavy ion fusion  

SciTech Connect

Large fusion devices will almost certainly produce net energy. However, a successful commercial fusion energy system must also satisfy important engineering and economic constraints. Inertial confinement fusion power plants driven by multi-stage, heavy-ion accelerators appear capable of meeting these constraints. The reasons behind this promising outlook for heavy-ion fusion are given in this report. This report is based on the transcript of a talk presented at the Symposium on Lasers and Particle Beams for Fusion and Strategic Defense at the University of Rochester on April 17-19, 1985.

Bangerter, R.O.

1985-10-01T23:59:59.000Z

48

Hadron Production in Heavy Ion Collisions  

E-Print Network (OSTI)

2A GeV 3 Hadron Production from AGS to RHIC 3.1 SystematicsHadron Production in Heavy Ion Collisions Hans Georg RitterAC02- 05CH11231. Hadron Production in Heavy Ion Collisions

Ritter, Hans Georg

2009-01-01T23:59:59.000Z

49

Synchrotron radiation by fast fermions in heavy-ion collisions  

SciTech Connect

We study the synchrotron radiation of gluons by fast quarks in strong magnetic field produced by colliding relativistic heavy ions. We argue that due to high electric conductivity of plasma, the magnetic field is almost constant during the entire plasma lifetime. We calculate the energy loss due to synchrotron radiation of gluons by fast quarks. We find that the typical energy loss per unit length for a light quark at the Large Hadron Collider is a few GeV per fm. This effect alone predicts quenching of jets with p{sub perpendicular} up to about 20 GeV. We also show that the spin-flip transition effect accompanying the synchrotron radiation leads to a strong polarization of quarks and leptons with respect to the direction of the magnetic field. Observation of the lepton polarization may provide a direct evidence of existence of strong magnetic field in heavy-ion collisions.

Tuchin, Kirill [Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States) and RIKEN BNL Research Center, Upton, New York 11973-5000 (United States)

2010-09-15T23:59:59.000Z

50

Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab  

Science Conference Proceedings (OSTI)

Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very beginning, the design studies at Jefferson Lab have focused on achieving high collider performance, particularly ultrahigh luminosities up to 10{sup 34} cm{sup -2}s{sup -1} per detector with large acceptance, while maintaining high polarization for both the electron and light-ion beams. These are the two key performance requirements of a future electron-ion collider facility as articulated by the NSAC Long Range Plan. In MEIC, a new ion complex is designed specifically to deliver ion beams that match the high bunch repetition and highly polarized electron beam from CEBAF. During the last two years, both development of the science case and optimization of the machine design point toward a medium-energy electron-ion collider as the topmost goal for Jefferson Lab. The MEIC, with relatively compact collider rings, can deliver a luminosity above 10{sup 34} cm{sup -2}s{sup -1} at a center-of-mass energy up to 65 GeV. It offers an electron energy up to 11 GeV, a proton energy up to 100 GeV, and corresponding energies per nucleon for heavy ions with the same magnetic rigidity. This design choice balances the scope of the science program, collider capabilities, accelerator technology innovation, and total project cost. An energy upgrade could be implemented in the future by adding two large collider rings housed in another large tunnel to push the center-of-mass energy up to or exceeding 140 GeV. After careful consideration of an alternative electron energy recovery linac on ion storage ring approach, a ring-ring collider scenario at high bunch repetition frequency was found to offer fully competitive performance while eliminating the uncertainties of challenging R&D on ampere-class polarized electron sources and many-pass energy-recovery linacs (ERLs). The essential new elements of an MEIC facility at Jefferson Lab are an electron storage ring and an entirely new, modern ion acceleration and storage complex. For the high-current electron collider ring, the upgraded 12 GeV CEBAF SRF linac will serve as a full-energy injector, and, if needed, provide top

Abeyratne, S; Ahmed, S; Barber, D; Bisognano, J; Bogacz, A; Castilla, A; Chevtsov, P; Corneliussen, S; Deconinck, W; Degtiarenko, P; Delayen, J; Derbenev, Ya; DeSilva, S; Douglas, D; Dudnikov, V; Ent, R; Erdelyi, B; Evtushenko, P; Fujii, Yu; Filatov, Yury; Gaskell, D; Geng, R; Guzey, V; Horn, T; Hutton, A; Hyde, C; Johnson, R; Kim, Y; Klein, F; Kondratenko, A; Kondratenko, M; Krafft, G; Li, R; Lin, F; Manikonda, S; Marhauser, F; McKeown, R; Morozov, V; Dadel-Turonski, P; Nissen, E; Ostroumov, P; Pivi, M; Pilat, F; Poelker, M; Prokudin, A; Rimmer, R; Satogata, T; Sayed, H; Spata, M; Sullivan, M; Tennant, C; Terzic, B; Tiefenback, M; Wang, M; Wang, S; Weiss, C; Yunn, B

2012-08-01T23:59:59.000Z

51

Heavy Ion Physics and Quark-Gluon Plasma  

E-Print Network (OSTI)

These proceedings represent a brief overview of the exciting physics coming out from the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The experimental results from BRAHMS, PHOBOS, PHENIX and STAR indicate a strongly-coupled state of matter that can only be described on the partonic level. Here we review some of the latest experimental results as presented at the meeting of the Division of Particles and Fields of the American Physical Society in Riverside, CA in August 2004.

J. L. Nagle

2004-11-15T23:59:59.000Z

52

HEAVY-ION RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY  

E-Print Network (OSTI)

In: Biological and Medical Research with Accelerated Heavyeds. Biological and Medical Research with Accelerated HeavyIn: Biological and Medical Research with Accelerated Heavy

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

53

Prospects for heavy flavor physics at hadron colliders  

SciTech Connect

The role of hadron colliders in the observation and study of CP violation in B decays is discussed. We show that hadron collider experiments can play a significant role in the early studies of these phenomena and will play an increasingly dominant role as the effort turns towards difficult to measure decays, especially those of the B{sub s} meson, and sensitive searches for rare decays and subtle deviations from Standard Model predictions. We conclude with a discussion of the relative merits of hadron collider detectors with `forward` vs `central` rapidity coverage.

Butler, J.N.

1997-09-01T23:59:59.000Z

54

Heavy ions and string theory  

E-Print Network (OSTI)

We review a selection of recent developments in the application of ideas of string theory to heavy ion physics. Our topics divide naturally into equilibrium and non-equilibrium phenomena. On the non-equilibrium side, we discuss generalizations of Bjorken flow, numerical simulations of black hole formation in asymptotically anti-de Sitter geometries, equilibration in the dual field theory, and hard probes. On the equilibrium side, we summarize improved holographic QCD, extraction of transport coefficients, inclusion of chemical potentials, and approaches to the phase diagram. We close with some possible directions for future research.

Oliver DeWolfe; Steven S. Gubser; Christopher Rosen; Derek Teaney

2013-04-29T23:59:59.000Z

55

Heavy ion physics at the LHC  

E-Print Network (OSTI)

Heavy Ion Physics at the LHC ? R. VogtLaboratory, Berkeley, CA USA Physics Department, Universityfor addressing unique physics issues in a completely new

Vogt, R.

2004-01-01T23:59:59.000Z

56

ON THE FEASIBILITY OF POLARIZED HEAVY IONS IN RHIC.  

Science Conference Proceedings (OSTI)

Heavy nonspherical ions such as uranium have been proposed for collisions in RHIC[1]. When two such ions collide with their long axes aligned parallel to the beams (large helicities), then the plasma density might be as much as 60% higher. Since the collisions might have any orientation of the two nuclei, the alignment of the nuclei must be inferred from a complicated unfolding of multiplicity distributions. Instead, if it would be possible to polarize the ions and control the orientation in RHIC, then a much better sensitivity might be obtained. This paper investigates the manipulation of such polarized ions with highly distorted shapes in RHIC. A number of ion species are considered as possibilities with either full or partial Siberian snakes in RHIC.

MACKAY, W.W.

2006-06-23T23:59:59.000Z

57

Beam losses from ultra-peripheral nuclear collisions between Pb ions in the Large Hadron Collider and their alleviation  

SciTech Connect

Electromagnetic interactions between colliding heavy ions at the Large Hadron Collider (LHC) at CERN will give rise to localized beam losses that may quench superconducting magnets, apart from contributing significantly to the luminosity decay. To quantify their impact on the operation of the collider, we have used a three-step simulation approach, which consists of optical tracking, a Monte-Carlo shower simulation and a thermal network model of the heat flow inside a magnet. We present simulation results for the case of {sup 208}Pb{sup 82+} ion operation in the LHC, with focus on the alice interaction region, and show that the expected heat load during nominal {sup 208}Pb{sup 82+} operation is 40% above the quench level. This limits the maximum achievable luminosity. Furthermore, we discuss methods of monitoring the losses and possible ways to alleviate their effect.

Bruce, R.; /CERN; Bocian, D.; /Fermilab /CERN; Gilardoni, S.; Jowett, J.M.; /CERN

2009-08-01T23:59:59.000Z

58

Heavy Ion Physics at the ATLAS Detector  

E-Print Network (OSTI)

The ATLAS detector is one of the two large detectors built to carry on high pT physics at the Large Hadron Collider. The detector is designed to perform optimally at the challenging nominal LHC machine luminosity of 10^34 cm-2s-1. ATLAS has a finely segmented electromagnetic and hadronic calorimeters covering 10 units of rapidity. The inner tracking system is composed of sicilicon pixel detector, silicon central tracker, transition radiation tracker and a 2T solenoidal magnet, covering 5 units of rapidity. The muon spectrometer is located outside the calorimeter volume. Muon chambers and air core toroids are used to track muons of momentum larger than 4 GeV. The ATLAS detector has a superb performance for jet physics because of its calorimeters. Simulation studies also indicate that it will be possible to tag b-jets in the heavy ion environment. Upsilon and J/Psi can be reconstructed through the di-muon decay channel. The detector is ideal for the study of global variables, namely total energy flow and ...

Takai, H; The ATLAS collaboration

2009-01-01T23:59:59.000Z

59

Ion desorption stability in superconducting high energy physics proton colliders  

DOE Green Energy (OSTI)

In this article we extend our previous analysis of a cold beam tube vacuum in a superconducting proton collider to include ion desorption in addition to thermal desorption and synchrotron radiation induced photodesorption. The ion desorption terms introduce the possibility of vacuum instability. This is similar to the classical room temperature case but is now modified by the inclusion of ion desorption coefficients for cryosorbed (physisorbed) molecules which can greatly exceed the coefficients for tightly bound molecules. The sojourn time concept for physisorbed H{sub 2} is generalized to include photodesorption and ion desorption as well as the usually considered thermal desorption. The ion desorption rate is density dependent and divergent so at the onset of instability the sojourn time goes to zero. Experimental data are used to evaluate the H{sub 2} sojourn time for the conditions of the Large Hadron Collider (LHC) and the situation is found to be stable. The sojourn time is dominated by photodesorption for surface density {ital s}(H{sub 2}) less than a monolayer and by thermal desorption for {ital s}(H{sub 2}) greater than a monolayer. For a few percent of a monolayer, characteristic of a beam screen, the photodesorption rate exceeds the ion desorption rate by more than two orders of magnitude. The photodesorption rate corresponds to a sojourn time of approximately 100 s. The article then turns to the evaluation of stability margins and the inclusion of gases heavier than H{sub 2} (CO, CO{sub 2}, and CH{sub 4}), where ion desorption introduces coupling between molecular species. Stability conditions are worked out for a simple cold beam tube, a cold beam tube pumped from the ends, and a cold beam tube with a coaxial perforated beam screen. In each case a simple inequality for stability of a single component is replaced by a determinant that must be greater than zero for a gas mixture. (Abstract Truncated)

Turner, W.C. [E. O. Lawrence Berkeley National Laboratory, University of California--Berkeley, Berkeley, California 94720 (United States)] [E. O. Lawrence Berkeley National Laboratory, University of California--Berkeley, Berkeley, California 94720 (United States)

1996-07-01T23:59:59.000Z

60

Heavy Ion Collisions at the LHC - Last Call for Predictions  

SciTech Connect

In August 2006, the CERN Theory Unit announced to restructure its visitor program and to create a 'CERN Theory Institute', where 1-3 month long specific programs can take place. The first such Institute was held from 14 May to 10 June 2007, focusing on 'Heavy Ion Collisions at the LHC - Last Call for Predictions'. It brought together close to 100 scientists working on the theory of ultra-relativistic heavy ion collisions. The aim of this workshop was to review and document the status of expectations and predictions for the heavy ion program at the Large Hadron Collider LHC before its start. LHC will explore heavy ion collisions at {approx} 30 times higher center of mass energy than explored previously at the Relativistic Heavy Ion Collider RHIC. So, on the one hand, the charge of this workshop provided a natural forum for the exchange of the most recent ideas, and allowed to monitor how the understanding of heavy ion collisions has evolved in recent years with the data from RHIC, and with the preparation of the LHC experimental program. On the other hand, the workshop aimed at a documentation which helps to distinguish pre- from post-dictions. An analogous documentation of the 'Last Call for Predictions' [1] was prepared prior to the start of the heavy-ion program at the Relativistic Heavy Ion Collider RHIC, and it proved useful in the subsequent discussion and interpretation of RHIC data. The present write-up is the documentation of predictions for the LHC heavy ion program, received or presented during the CERN TH Institute. The set-up of the CERN TH Institute allowed us to aim for the wide-most coverage of predictions. There were more than 100 presentations and discussions during the workshop. Moreover, those unable to attend could still participate by submitting predictions in written form during the workshop. This followed the spirit that everybody interested in making a prediction had the right to be heard. To arrive at a concise document, we required that each prediction should be summarized on at most two pages, and that predictions should be presented, whenever possible, in figures which display measurable quantities. Full model descriptions were not accepted--the authors were encouraged to indicate the relevant references for the interested reader. Participants had the possibility to submit multiple contributions on different topics, but it was part of the subsequent editing process to ensure that predictions on neighboring topics were merged wherever possible. The contributions summarized here are organized in several sections,--though some of them contain material related with more than one section--roughly by going from low transverse momentum to high transverse momentum and from abundant to rare measurements. In the low transverse momentum regime, we start with predictions on multiplicity distributions, azimuthal asymmetries in particle production and hadronic flavor observables, followed by correlation and fluctuation measurements. The contributions on hard probes at the LHC start with predictions for single inclusive high transverse momentum spectra, and jets, followed by heavy quark and quarkonium measurements, leptonic probes and photons. A final section 'Others' encompasses those predictions which do not fall naturally within one of the above-mentioned categories, or discuss the more speculative phenomena that may be explored at the LHC.

Armesto, N; Borghini, N; Jeon, S; Wiedemann, U A; Abreu, S; Akkelin, V; Alam, J; Albacete, J L; Andronic, A; Antonuv, D; Arleo, F; Armesto, N; Arsene, I C; Barnafoldi, G G; Barrette, J; Bauchle, B; Becattini, F; Betz, B; Bleicher, M; Bluhm, M; Boer, D; Bopp, F W; Braun-Munzinger, P; Bravina, L; Busza, W; Cacciari, M; Capella, A; Casalderrey-Solana, J; Chatterjee, R; Chen, L; Cleymans, J; Cole, B A; delValle, Z C; Csernai, L P; Cunqueiro, L; Dainese, A; de Deus, J D; Ding, H; Djordjevic, M; Drescher, H; Dremin, I M; Dumitru, A; El, A; Engel, R; d' Enterria, D; Eskola, K J; Fai, G; Ferreiro, E G; Fries, R J; Frodermann, E; Fujii, H; Gale, C; Gelis, F; Goncalves, V P; Greco, V; Gyulassy, M; van Hees, H; Heinz, U; Honkanen, H; Horowitz, W A; Iancu, E; Ingelman, G; Jalilian-Marian, J; Jeon, S; Kaidalov, A B; Kampfer, B; Kang, Z; Karpenko, I A; Kestin, G; Kharzeev, D; Ko, C M; Koch, B; Kopeliovich, B; Kozlov, M; Kraus, I; Kuznetsova, I; Lee, S H; Lednicky, R; Letessier, J; Levin, E; Li, B; Lin, Z; Liu, H; Liu, W; Loizides, C; Lokhtin, I P; Machado, M T; Malinina, L V; Managadze, A M; Mangano, M L; Mannarelli, M; Manuel, C; Martinez, G; Milhano, J G; Mocsy, A; Molnar, D; Nardi, M; Nayak, J K; Niemi, H; Oeschler, H; Ollitrault, J; Paic, G; Pajares, C; Pantuev, V S; Papp, G; Peressounko, D; Petreczky, P; Petrushanko, S V; Piccinini, F; Pierog, T; Pirner, H J; Porteboeuf, S; Potashnikova, I; Qin, G Y; Qiu, J; Rafelski, J; Rajagopal, K; Ranft, J; Rapp, R; Rasanen, S S; Rathsman, J; Rau, P; Redlich, K; Renk, T; Rezaeian, A H; Rischke, D; Roesler, S; Ruppert, J; Ruuskanen, P V; Salgado, C A; Sapeta, S; Sarcevic, I; Sarkar, S; Sarycheva, L I; Schmidt, I; Shoski, A I; Sinha, B; Sinyukov, Y M; Snigirev, A M; Srivastava, D K; Stachel, J; Stasto, A; Stocker, H; Teplov, C Y; Thews, R L; Torrieri, G; Pop, V T; Triantafyllopoulos, D N; Tuchin, K L; Turbide, S; Tywoniuk, K; Utermann, A; Venugopalan, R; Vitev, I; Vogt, R; Wang, E; Wang, X N; Werner, K; Wessels, E; Wheaton, S; Wicks, S; Wiedemann, U A; Wolschin, G; Xiao, B; Xu, Z; Yasui, S; Zabrodin, E; Zapp, K; Zhang, B

2008-02-25T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Crab Crossing Schemes and Studies for Electron Ion Collider  

Science Conference Proceedings (OSTI)

This report shows our progress in crab crossing consideration for future electron-ion collider envisioned at JLab. In this design phase, we are evaluating two crabbing schemes viz., the deflecting and dispersive. The mathematical formulations and lattice design for these schemes are discussed in this paper. Numerical simulations involving particle tracking through a realistic deflecting RF cavity and optics illustrate the desired crab tilt of 25 mrad for 1.35 MV. Evolution of beam propagation are shown which provides the physical insight of the crabbing phenomenon.

S. Ahmed, Y. Derbenev, V. Morozov, A. Castilla, G.A. Krafft, B. Yunn, Y. Zhang, J.R. Delayen

2011-09-01T23:59:59.000Z

62

Ferroelectric Plasma Source for Heavy Ion Beam Charge Neutralization  

E-Print Network (OSTI)

Heavy Ion Beam Driven Fusion Reactor Study, KfK-3480,a possible heavy ion fusion reactor design [1]. The final

2005-01-01T23:59:59.000Z

63

Studies in ion source development for application in heavy ion fusion  

E-Print Network (OSTI)

Ion Sources for Heavy Ion Fusion Applications . Ph.D.Sources for Heavy Ion Fusion . Proceedings of the ParticleDevelopment for Heavy Ion Fusion. Wollnik, H. , Optics of

Kapica, Jonathan G.

2004-01-01T23:59:59.000Z

64

A 3 MEGAJOULE HEAVY ION FUSION DRIVER  

E-Print Network (OSTI)

Research, Office of Inertia! Fusion, Research Division ofA 3 MEGAJOULE HEAVY ION FUSION DRIVER* A. Faltens, E. Hoyer,Research, Office of Inertial Fusion, Research Division of

Faltens, A.

2010-01-01T23:59:59.000Z

65

Hadron Production in Heavy Ion Collisions  

E-Print Network (OSTI)

We review hadron production in heavy ion collisions with emphasis on pion and kaon production at energies below 2 AGeV and on partonic collectivity at RHIC energies.

Helmut Oeschler; Hans Georg Ritter; Nu Xu

2009-08-12T23:59:59.000Z

66

Electron Ion Collider: The Next QCD Frontier Understanding  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Electron Ion Collider: The Next QCD Frontier Understanding the glue that binds us all White Paper Writing Committee Elke C. Aschenauer Brookhaven National Laboratory William Brooks Universidad T´ ecnica Federico Santa Maria Abhay Deshpande 1 Stony Brook University Markus Diehl Deutsches Elektronen-Synchrotron DESY Haiyan Gao Duke University Roy Holt Argonne National Laboratory Tanja Horn The Catholic University of America Andrew Hutton Thomas Jefferson National Accelerator Facility Yuri Kovchegov The Ohio State University Krishna Kumar University of Massachusetts, Amherst Zein-Eddine Meziani 1 Temple University Alfred Mueller Columbia University Jianwei Qiu 1 Brookhaven National Laboratory Michael Ramsey-Musolf University of Wisconsin Thomas Roser Brookhaven National Laboratory 1 Co-Editor 1 Franck Sabati´ e Commissariat ` a l' ´ Energie Atomique-Saclay

67

High Current Ion Sources and Injectors for Heavy Ion Fusion  

E-Print Network (OSTI)

2001). [40] L.R. Grisham, Fusion Sci. & Tech. 43, 191, (Symp. on Heavy Ion Inertial Fusion, Princeton, New Jersey,Sept. 6-9, 1995; in Fusion Engineering and Design, 32-33,

Kwan, Joe W.

2005-01-01T23:59:59.000Z

68

Home of eRHIC: the Electron-Ion-Collider at BNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Ion Collider (EIC) Project Web Page Electron Ion Collider (EIC) Project Web Page This webpage is perpetually under construction October 26, 2007 (Maintained by Abhay Deshpande) A high luminosity polarized e-p/He and unpolarized e-A collider to study the hyperfine structure of the nucleon including (spin and flavor) and to explore nuclear matter at high parton densities. EIC Collaboration WebPage EIC Meeting at SBU, December 7-8, 2007 The most recent meeting: EICC meeting at MIT, May 2007 A Joint EIC2006 (Third Electron Ion Collider) and Hot-QCD Workshop hosted by BNL, July 17-22, 2006 eRHIC Related Papers and other Material White Papers & other information and documents for NSAC Long Range Planning 2007 Study of fundamental structure of matter with an electron-ion collider, A.

69

Bound-Free Electron-Positron Pair Production in Relativistic Heavy-Ion Collisions  

E-Print Network (OSTI)

The bound-free electron-positron pair production is considered for relativistic heavy ion collisions. In particular, cross sections are calculated for the pair production with the simultaneous capture of the electron into the 1s ground state of one of the ions and for energies that are relevant for the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Colliders (LHC). In the framework of perturbation theory, we applied Monte-Carlo integration techniques to compute the lowest-order Feynman diagrams amplitudes by using Darwin wave functions for the bound states of the elec- trons and Sommerfeld-Maue wave functions for the continuum states of the positrons. Calculations were performed especially for the collision of Au + Au at 100 GeV/nucleon and Pb + Pb at 3400 GeV/nucleon.

M. Y. Sengul; M. C. Guclu; S. Fritzsche

2009-07-30T23:59:59.000Z

70

Design of Electron and Ion Crabbing Cavities for an Electron-Ion Collider  

SciTech Connect

Beyond the 12 GeV upgrade at the Jefferson Lab a Medium Energy Electron-Ion Collider (MEIC) has been considered. In order to achieve the desired high luminosities at the Interaction Points (IP), the use of crabbing cavities is under study. In this work, we will present to-date designs of superconducting cavities, considered for crabbing both ion and electron bunches. A discussion of properties such as peak surface fields and higher-order mode separation will be presented. Keywords: super conducting, deflecting cavity, crab cavity.

Alejandro Castilla Loeza, Geoffrey Krafft, Jean Delayen

2012-07-01T23:59:59.000Z

71

Probing the Quark Sea and Gluons: the Electron-Ion Collider Projects  

Science Conference Proceedings (OSTI)

EIC is the generic name for the nuclear science-driven Electron-Ion Collider presently considered in the US. Such an EIC would be the worlds first polarized electron-proton collider, and the worlds first e-A collider. Very little remains known about the dynamical basis of the structure of hadrons and nuclei in terms of the fundamental quarks and gluons of Quantum Chromodynamics (QCD). A large community effort to sharpen a compelling nuclear science case for an EIC occurred during a ten-week program taking place at the Institute for Nuclear Theory (INT) in Seattle from September 13 to November 19, 2010. The critical capabilities of a stage-I EIC are a range in center-of-mass energies from 20 to 70 GeV and variable, full polarization of electrons and light ions (the latter both longitudinal and transverse), ion species up to A=200 or so, multiple interaction regions, and a high luminosity of about 10{sup 34} electron-nucleons per cm{sup 2} and per second. The physics program of such a stage-I EIC encompass inclusive measurements (ep/A{yields}e'+X), which require detection of the scattered lepon and/or the full scattered hadronic debris with high precision, semi-inclusive processes (ep/A{yields}e'+h+X), which require detection in coincidence with the scattered lepton of at least one (current or target region) hadron; and exclusive processes (ep/A{yields}e'+N'/A'+{gamma}/m), which require detection of all particles in the reaction. The main science themes of an EIC are to i) map the spin and spatial structure of quarks and gluons in nucleons, ii) discover the collective effects of gluons in atomic nuclei, and (iii) understand the emergence of hadronic matter from color charge. In addition, there are opportunities at an EIC for fundamental symmetry and nucleon structure measurements using the electroweak probe. To truly make headway to image the sea quarks and gluons in nucleons and nuclei, the EIC needs high luminosity over a range of energies as more exclusive scattering probabilities are small, and any integrated detector/interaction region design needs to provide uniform coverage to detect spectator and diffractive products. This is because e-p and even more e-A colliders have a large fraction of their science related to what happens to the nucleon or ion beams. As a result, the philosophy of integration of complex detectors into an extended interaction region faces challenging constraints. Designs feature crossing angles between the protons or heavy ions during collisions with electrons, to remove potential problems for the detector induced by synchrotron radiation. Designs allocate quite some detector space before the final-focus ion quads, at the cost of luminosity, given that uniform detection coverage is a must for deep exclusive and diffractive processes. The integrated EIC detector/interaction region design at JLab focused on establishing full acceptance for such processes over a wide range of proton energies (20-100 GeV) with well achievable interaction region magnets. The detector design at BNL uses the higher ion beam energies to achieve good detection efficiency for instance for protons following a DVCS reaction, for proton beam energies starting from 100 GeV. Following a recommendation of the 2007 US Nuclear Science Long-Range Planning effort, the DOE Office of Nuclear Physics (DOE/NP) has allocated accelerator R&D funds to lay the foundation for a polarized EIC. BNL, in association with JLab and DOE/NP, has also established a generic detector R&D program to address the scientific requirements for measurements at a future EIC.

Rolf Ent

2012-04-01T23:59:59.000Z

72

Carbon foils as heavy ion strippers  

SciTech Connect

A discussion is given of the advantages and disadvantages of thin carbon foil strippers for heavy ion beams from tandem electrostatic accelerators. Foil lifetimes were increased by radiative heating and by the evaporation of a thin layer of gold on the foil. (PMA)

Yntema, J.L.

1975-01-01T23:59:59.000Z

73

YEAR-END REPORT: HEAVY ION FUSION PROGRAM  

E-Print Network (OSTI)

1978-Mar. 1979, Heavy Ion Fusion Program, Lawrence BerkeleyOlson, Proceedings of the Heavy Ion Fusion Workshop, ArgonneUniversity Ravi N. Sudan KMS Fusion, Inc. Stanford Linear

Fusion Staff, Heavy Ion

2010-01-01T23:59:59.000Z

74

INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS  

E-Print Network (OSTI)

HIFAN 1830 INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMSAC02-05CH11231. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION467 (1992). [38] R. W. Moir, Fusion Tech. 25, 5 (1994) [39

Sharp, W. M.

2011-01-01T23:59:59.000Z

75

The high current transport experiment for heavy ion inertial fusion  

E-Print Network (OSTI)

on Heavy Ion Inertial Fusion, Princeton, 1996, edited by J.Conference on Inertial Fusion Sciences and Applications (FOR HEAVY ION INERTIAL FUSION 1 L. R. Prost, D. Baca, F. M.

2004-01-01T23:59:59.000Z

76

The Modular Point Design for Heavy Ion Fusion  

E-Print Network (OSTI)

POINT DESIGN FOR HEAVY ION FUSION S.S. Yu 1 , J.J. BarnardUpdated Point Design for Heavy Ion Fusion, Proc. 2002 Amer.Nucl. Soc. Fusion Topical Meeting, 17-21 November 2002,

2004-01-01T23:59:59.000Z

77

High-energy accelerator for beams of heavy ions  

DOE Patents (OSTI)

An apparatus for accelerating heavy ions to high energies and directing the accelerated ions at a target comprises a source of singly ionized heavy ions of an element or compound of greater than 100 atomic mass units, means for accelerating the heavy ions, a storage ring for accumulating the accelerated heavy ions and switching means for switching the heavy ions from the storage ring to strike a target substantially simultaneously from a plurality of directions. In a particular embodiment the heavy ion that is accelerated is singly ionized hydrogen iodide. After acceleration, if the beam is of molecular ions, the ions are dissociated to leave an accelerated singly ionized atomic ion in a beam. Extraction of the beam may be accomplished by stripping all the electrons from the atomic ion to switch the beam from the storage ring by bending it in magnetic field of the storage ring.

Martin, Ronald L. (La Grange, IL); Arnold, Richard C. (Chicago, IL)

1978-01-01T23:59:59.000Z

78

Multiple Electron Stripping of Heavy Ion Beams  

DOE Green Energy (OSTI)

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 Mev/amu with charge state 1 currently do not exist. Hence, the stripping cross-sections used to model the performance of heavy ion fusion driver beams have, up to now, been based upon theoretical calculations. We have investigated experimentally the stripping of 3.4 Mev/amu Kr 7+ and Xe +11 in N2; 10.2 MeV/amu Ar +6 in He, N2, Ar and Xe; 19 MeV/amu Ar +8 in He, N2, Ar and Xe; 30 MeV He 1 + in He, N2, Ar and Xe; and 38 MeV/amu N +6 in He, N2, Ar and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

D. Mueller; L. Grisham; I. Kaganovich; R. L. Watson; V. Horvat; K. E. Zaharakis; Y. Peng

2002-06-25T23:59:59.000Z

79

Photon production from non-equilibrium QGP in heavy ion collisions  

E-Print Network (OSTI)

We present a calculation of thermal photon production i.e. photons from secondary interactions among particles produced in heavy ion collisions at collider energies. This is done within the framework of hydrodynamics. We take into account the lack of chemical equilibrium in QGP. It turns out that main effects from chemical non-equilibrium composition of QGP, reduction of particle number and increase in temperature, nearly cancel in photon spectrum.

F. Gelis; H. Niemi; P. V. Ruuskanen; S. S. Rasanen

2004-03-15T23:59:59.000Z

80

Dragging Heavy Quarks in Quark Gluon Plasma at the Large Hadron Collider  

E-Print Network (OSTI)

The drag and diffusion coefficients of charm and bottom quarks propagating through quark gluon plasma (QGP) have been evaluated for conditions relevant to nuclear collisions at Large Hadron Collider (LHC). The dead cone and Landau-Pomeronchuk-Migdal (LPM) effects on radiative energy loss of heavy quarks have been considered. Both radiative and collisional processes of energy loss are included in the {\\it effective} drag and diffusion coefficients. With these effective transport coefficients we solve the Fokker Plank (FP) equation for the heavy quarks executing Brownian motion in the QGP. The solution of the FP equation has been used to evaluate the nuclear suppression factor, $R_{\\mathrm AA}$ for the non-photonic single electron spectra resulting from the semi-leptonic decays of hadrons containing charm and bottom quarks. The effects of mass on $R_{\\mathrm AA}$ has also been highlighted.

Santosh K Das; Jan-e Alam; Payal Mohanty

2010-03-29T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Medium energy heavy ion operations at RHIC  

Science Conference Proceedings (OSTI)

As part of the search for a phase transition or critical point on the QCD phase diagram, an energy scan including 5 different energy settings was performed during the 2010 RHIC heavy ion run. While the top beam energy for heavy ions is at 100 GeV/n and the lowest achieved energy setpoint was significantly below RHICs injection energy of approximately 10 GeV/n, we also provided beams for data taking in a medium energy range above injection energy and below top beam energy. This paper reviews RHIC experience and challenges for RHIC medium energy operations that produced full experimental data sets at beam energies of 31.2 GeV/n and 19.5 GeV/n. The medium energy AuAu run covered two beam energies, both above the RHIC injection energy of 9.8 GeV but well below the standard store energy of 100 GeV (see table 1). The low energy and full energy runs with heavy ions in FY10 are summarized in [1] and [2]. Stochastic Cooling ([3]) was only used for 100 GeV beams and not used in the medium energy run. The efficiency of the transition from 100 GeV operation to 31.2 GeV and then to 19.5 GeV was remarkable. Setup took 32 h and 19 h respectively for the two energy settings. The time in store, defined to be the percentage of time RHIC provides beams in physics conditions versus calendar time, was approximately 52% for the entire FY10 heavy ion run. In both medium energy runs it was well above this average, 68% for 31.5 GeV and 82% for 19.5 GeV. For both energies RHIC was filled with 111 bunches with 1.2 10{sup 9} and 1.3 10{sup 9} ions per bunch respectively.

Drees, K.A.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blackler, I.M.C.; Blaskiewicz, M.; Brown, K.A.; Brennan, M.; Bruno, D.; Butler, J.; Carlson, C.; Connolly, R.; D'Ottavio, T.; Fischer, W.; Fu, W.; Gassner, D.; Harvey, M.; Hayes, T.; Huang, H.; Hulsart, R.; Ingrassia, P.; Kling, N.; Lafky, M.; Laster, J.; Lee, R.C.; Litvinenko, V.; Luo, Y.; MacKay, W.W.; Marr, G.; Mapes. M.; Marusic, A.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Naylor, C.; Nemesure, S.; Pilat, F.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Sampson, P.; Satogata, T.; Schoefer, V.; Schultheiss, C.; Severino, F.; Shrey, T.; Smith, K.S.; Tepikian, S.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; van Kuik, B.; Wilinski, M.; Zaltsman, A.; Zeno, K.; Zhang, S.Y.

2011-03-28T23:59:59.000Z

82

Diamond Detectors for Heavy Ion Measurements  

E-Print Network (OSTI)

In 1999, the accelerator facility at GSI is scheduled to deliver beam intensities of about 10 10 particles/spill for all available ions up to 238 U. This necessitates the development of a new generation of radiation-resistant and ultra-fast detectors, in conjunction with new high-speed and low-noise electronics. Preliminary results confirm the suitability of CVD-diamond detectors for both, beam diagnostics, and heavy-ion experiments with projectiles in the energy region from 50 MeV/amu to 2 GeV/amu. Various test measurements

E. Berdermann; K. Blasche; P. Moritz; H. Stelzer; F. Zeytouni

1998-01-01T23:59:59.000Z

83

A Radiographic Technique With Heavy Ion Microbeams  

SciTech Connect

In this work, we introduce a new technique to perform densitometric and multielemental analysis of samples at the same time using a simple detector with heavy ion micro-beams. It consists in the simultaneous analysis of X-rays induced in the sample and in a secondary target arranged behind the specimen. The X-rays originated in the secondary target are attenuated when crossing the specimen producing a radiographic image with a monochromatic source.

Muscio, J. [ECyT, UNSAM, 1650 San Martin, Buenos Aires (Argentina); Somacal, H.; Burlon, A. A.; Debray, M. E.; Valda, A. A. [ECyT, UNSAM, 1650 San Martin, Buenos Aires (Argentina); U.A. Fisica, Laboratorio TANDAR, CNEA, 1650 San Martin, Buenos Aires (Argentina); Kreiner, A. J. [U.A. Fisica, Laboratorio TANDAR, CNEA, 1650 San Martin, Buenos Aires (Argentina); ECyT, UNSAM, 1650 San Martin, Buenos Aires (Argentina); CONICET (Argentina); Kesque, J. M.; Minsky, D. M. [U.A. Fisica, Laboratorio TANDAR, CNEA, 1650 San Martin, Buenos Aires (Argentina)

2007-02-12T23:59:59.000Z

84

Heavy Ion Fusion Systems Assessment study  

SciTech Connect

The Heavy Ion Fusion Systems Assessment (HIFSA) study was conducted with the specific objective of evaluating the prospects of using induction linac drivers to generate economical electrical power from inertial confinement fusion. The study used algorithmic models of representative components of a fusion system to identify favored areas in the multidimensional parameter space. The resulting cost-of-electricity (COE) projections are comparable to those from other (magnetic) fusion scenarios, at a plant size of 100 MWe.

Dudziak, D.J.; Herrmannsfeldt, W.B.

1986-07-01T23:59:59.000Z

85

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.of a Heavy Ion Fusion reactor heavily depends on the maximum

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

86

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.efficiency of a Heavy Ion Fusion reactor heavily depends on

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

87

Heavy flavor in heavy-ion collisions at RHIC and RHIC II  

E-Print Network (OSTI)

In the initial years of operation, experiments at the Relativistic Heavy Ion Collider (RHIC) have identified a new form of matter formed in nuclei-nuclei collisions at energy densities more than 100 times that of a cold atomic nucleus. Measurements and comparison with relativistic hydrodynamic models indicate that the matter thermalizes in an unexpectedly short time, has an energy density at least 15 times larger than needed for color deconfinement, has a temperature about twice the critical temperature predicted by lattice QCD, and appears to exhibit collective motion with ideal hydrodynamic properties - a "perfect liquid" that appears to flow with a near-zero viscosity to entropy ratio - lower than any previously observed fluid and perhaps close to a universal lower bound. However, a fundamental understanding of the medium seen in heavy-ion collisions at RHIC does not yet exist. The most important scientific challenge for the field in the next decade is the quantitative exploration of the new state of nuclear matter. That will require new data that will, in turn, require enhanced capabilities of the RHIC detectors and accelerator. In this report we discuss the scientific opportunities for an upgraded RHIC facility - RHIC II - in conjunction with improved capabilities of the two large RHIC detectors, PHENIX and STAR. We focus solely on heavy flavor probes. Their production rates are calculable using the well-established techniques of perturbative QCD and their sizable interactions with the hot QCD medium provide unique and sensitive measurements of its crucial properties making them one of the key diagnostic tools available to us.

A. D. Frawley; T. Ullrich; R. Vogt

2008-06-05T23:59:59.000Z

88

Elliptic flow of thermal photons in heavy-ion collisions at Relativistic Heavy Ion Collider and Large Hadron Collider  

E-Print Network (OSTI)

We calculate the thermal photon transverse momentum spectra and elliptic flow in $\\sqrt{s_{NN}} = 200$ GeV Au+Au collisions at RHIC and in $\\sqrt{s_{NN}} = 2.76$ TeV Pb+Pb collisions at the LHC, using an ideal-hydrodynamical framework which is constrained by the measured hadron spectra at RHIC and LHC. The sensitivity of the results to the QCD-matter equation of state and to the photon emission rates is studied, and the photon $v_2$ is discussed in the light of the photonic $p_T$ spectrum measured by the PHENIX Collaboration. In particular, we make a prediction for the thermal photon $p_T$ spectra and elliptic flow for the current LHC Pb+Pb collisions.

Hannu Holopainen; Sami Rsnen; Kari J. Eskola

2011-04-28T23:59:59.000Z

89

Design of the Proposed Low Energy Ion Collider Ring at Jefferson Lab  

SciTech Connect

The polarized Medium energy Electron-Ion Collider (MEIC) envisioned at Jefferson Lab will cover a range of center-of-mass energies up to 65 GeV. The present MEIC design could also allow the accommodation of low energy electron-ion collisions (LEIC) for additional science reach. This paper presents the first design of the low energy ion collider ring which is converted from the large ion booster of MEIC. It can reach up to 25 GeV energy for protons and equivalent ion energies of the same magnetic rigidity. An interaction region and an electron cooler designed for MEIC are integrated into the low energy collider ring, in addition to other required new elements including crab cavities and ion spin rotators, for later reuse in MEIC itself. A pair of vertical chicanes which brings the low energy ion beams to the plane of the electron ring and back to the low energy ion ring are also part of the design.

Nissen, Edward W. [JLAB; Lin, Fanglei [JLAB; Morozov, Vasiliy [JLAB; Zhang, Yuhong [JLAB

2013-06-01T23:59:59.000Z

90

Using Microwave Radiation for Removing Heavy Metal Ions and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Using Microwave Radiation for Removing Heavy Metal Ions and Producing Biofuels. Author(s), Aharon Gedanken. On-Site Speaker (Planned )...

91

LEIC - A Polarized Low Energy Electron-ion Collider at Jefferson Lab  

Science Conference Proceedings (OSTI)

A polarized electron-ion collider is envisioned as the future nuclear science program at JLab beyond the 12 GeV CEBAF. Presently, a medium energy collider (MEIC) is set as an immediate goal with options for a future energy upgrade. A comprehensive design report for MEIC has been released recently. The MEIC facility could also accommodate electron and proton/ion collisions in a low CM energy range, covering proton energies from 10 to 25 GeV and ion energies with a similar magnetic rigidity, for additional science reach. In this paper, we present a conceptual design of this low energy collider, LEIC, showing its luminosity can reach above 10{sup 33} cm{sup -2}s{sup -1}. The design specifies that the large booster of the MEIC is converted to a low energy ion collider ring with an interaction region and an electron cooler integrated into it. The design provides options for either sharing the detector with the MEIC or a dedicated low energy detector in a third collision point, with advantages of either a minimum cost or extra detection parallel to the MEIC operation, respectively. The LEIC could be positioned as the first and low cost phase of a multi-stage approach to realize the full MEIC.

Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Hutton, Andrew M. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Krafft, Geoffrey A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Lin, Fanglei [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Morozov, Vasiliy [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Nissen, Edward W. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Yunn, Byung C. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, He [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Sullivan, Michael K. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2013-06-01T23:59:59.000Z

92

Charm elliptic flow in relativistic heavy-ion collisions RID A-2398-2009  

E-Print Network (OSTI)

Charm elliptic flow in heavy-ion collisions at the Relativistic Heavy Ion Collider is studied in a multiphase transport model. Assuming that the cross section for charm quark scattering with other light quarks is the same as that between light quarks, we find that both charm and light quark elliptic flows are sensitive to the value of the cross section. Compared to that of light quarks, the elliptic flow of charm quarks is smaller at low transverse momentum but approaches comparable values at high transverse momentum. Similar features are seen in the elliptic flow of charmed mesons as well as that of the electrons from their semileptonic decays when the charmed mesons are produced from quark coalescence during hadronization of the partonic matter. To describe the large electron elliptic flow observed in available experimental data requires a charm quark-scattering cross section that is much larger than that given by the perturbative quantum chromodynamics.

Zhang, B.; Chen, LW; Ko, Che Ming.

2005-01-01T23:59:59.000Z

93

The Heavy Ion Fusion Science Virtual National Laboratory Status of heavy-ion-beam-driven  

E-Print Network (OSTI)

and fusion Ranges given in table reflect options under study Table 4.1, page 43 of an HIF White Paper.E. Coleman et al., in Proc. of the 2007 Particle Accelerator Conf., Albuquerque, NM, 2007(IEEE catalog# 07CH-see http://videos.komando.com/2008/08/19/water-painting/]. #12;12/7/08 The Heavy Ion Fusion Science Virtual

94

Triangular flow in heavy ion collisions in a multiphase transport model  

E-Print Network (OSTI)

We obtain a new set of parameters in a multiphase transport (AMPT) model that are able to describe both the charged particle multiplicity density and the elliptic flow measured in Au + Au collisions at center-of-mass energy root(S)NN = 200 GeV at the Relativistic Heavy Ion Collider, although they still give somewhat softer transverse momentum spectra. We then use the model to predict the triangular flow due to fluctuations in the initial collision geometry and study its effect relative to those from other harmonic components of anisotropic flows on the dihadron azimuthal correlations in both central and midcentral collisions.

Xu, Jun; Ko, Che Ming.

2011-01-01T23:59:59.000Z

95

Develpoment of a one-meter plasma source for heavy ion beam charge neutralization  

E-Print Network (OSTI)

Heavy Ion Beam Driven Fusion Reactor Study, KfK-3480,is a possible heavy ion fusion reactor design [1]. The final

2005-01-01T23:59:59.000Z

96

Report of the Ad Hoc Panel on heavy ion facilities  

SciTech Connect

In response to a request from the USAEC, the President of the National Academy of Sciences appointed an Ad Hoc Panel under the NAS-NRC Committee on Nuclear Science to make an intensive study of various aspects of the science and technology involved in heavy ion research in light of the needs of the national program in this field. In particular, the panel was asked to formulate and evaluate various options for the development of heavy ion facilities that would include an appropriate accelerator complex capable of producing heavy ion beams and the ancillary apparatus required for experimental exploitation. Also, the Panel was asked to evaluate the current status and potentialities of the Super HILAC and Bevalac accelerators of the Lawrence Radiation Laboratory, Berkeley. Results of the study are presented. Topics include heavy ions in nuclear physics and chemistry, atomic physics, heavy ions and astro and space physics, materials science and solid state, and biomedicine. The state of the technology related to the choice of a heavy ion accelerator system is reviewed, and the various possible choices are reviewed including the large tandem accelerator, tandem- cyclotron systems, and linear accelerators. The upgrading of existing facilities (Super HILAC, Bevalac, and PPA) is discussed. Cost estimates for various heavy ion facilities are briefly discussed. (WHK)

1974-01-01T23:59:59.000Z

97

Long ion chamber systems for the SLC (Stanford Linear Collider)  

Science Conference Proceedings (OSTI)

A Panofsky Long Ion Chamber (PLIC) is essentially a gas-filled coaxial cable, and has been used to protect the Stanford Linear Accelerator from damage caused by its electron beam, and as a sensitive diagnostic tool. This old technology has been updated and has found renewed use in the SLC. PLIC systems have been installed as beam steering aids in most parts of the SLC and are a part of the system that protects the SLC from damage by errant beams in several places. 5 refs., 3 figs., 1 tab.

Rolfe, J.; Gearhart, R.; Jacobsen, R.; Jenkins, T.; McComick, D.; Nelson, R.; Reagan, D.; Ross, M.

1989-03-01T23:59:59.000Z

98

Sandia National Labs: PCNSC: Heavy Ion Backscattering Spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

Heavy Ion Backscattering Spectrometry (HIBS) Heavy Ion Backscattering Spectrometry (HIBS) IBA Table (HTML) | IBA Table (135KB GIF) | IBA Table (1.2MB PDF) | IBA Table (33MB TIF) | Heavy Ion Backscattering Spectrometry (HIBS) | Virtual Lab Tour (6MB) Description of Technique: HIBS is used to detect ultra-trace levels of heavy impurities on the surface of a Si wafer. HIBS has advantages over TXRF, including: Improved sensitivity for most elements Quantifying composition without standards Measurement on rough surfaces. HIBS is accomplished by focusing a 120 keV beam of C+ions onto a small spot at the wafer's surface. The backscattered ions are collected by a time-of-flight (TOF) detector array with a large solid angle. The flight time of the backscattered C identifies the near-surface impurities and the

99

The Science Case for An Electron-Ion Collider: The Next QCD Frontier  

NLE Websites -- All DOE Office Websites (Extended Search)

Case for Case for An Electron-Ion Collider: The Next QCD Frontier Jianwei Qiu Brookhaven National Laboratory NSAC Subcommittee Meeting on Scientific Facilities February 15-16, 2013 for both BNL and JLab EIC efforts, ... 1 White Paper for the Electron-Ion Collider ELIC (JLab) eRHIC (BNL) 2 arXiv:1212.1701 Community effort and commitment Ten-week program (9/13-11/19, 2010) at Institute for Nuclear Theory (INT Report: arXiv:1108.1713v2, 500+ pages)  Many workshops on EIC physics: 3  Commitment from BNL and JLab:  EICAC - jointly by BNL and JLab  BNL EIC Task force (https://wiki.bnl.gov/eic/index.php/Main_Page)  EIC@JLab (https://eic.jlab.org/wiki/index.php/Main_Page)  Detector R&D (https://wiki.bnl.gov/conferences/index.php/EIC_R%25D)

100

Inertially confined fusion using heavy ion drivers  

Science Conference Proceedings (OSTI)

The various technical issues of HIF will be briefly reviewed in this paper. It will be seen that there are numerous areas in common in all the approaches to HIF. In the recent International Symposium on Heavy Ion Inertial Fusion, the attendees met in specialized workshop sessions to consider the needs for research in each area. Each of the workshop groups considered the key questions of this report: (1) Is this an appropriate time for international collaboration in HIF (2) Which problems are most appropriate for such collaboration (3) Can the sharing of target design information be set aside until other driver and systems issues are better resolved, by which time it might be supposed that there could be a relaxation of classification of target issues (4) What form(s) of collaboration are most appropriate, e.g., bilateral or multilateral (5) Can international collaboration be sensibly attempted without significant increases in funding for HIF The authors of this report share the conviction that collaboration on a broad scale is mandatory for HIF to have the resources, both financial and personnel, to progress to a demonstration experiment. Ultimately it may be possible for a single driver with the energy, power, focusibility, and pulse shape to satisfy the needs of the international community for target physics research. Such a facility could service multiple experimental chambers with a variety of beam geometries and target concepts.

Herrmannsfeldt, W.B. (Stanford Linear Accelerator Center, Menlo Park, CA (United States)); Bangerter, R.O. (Lawrence Berkeley Lab., CA (United States)); Bock, R. (Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)); Hogan, W.J.; Lindl, J.D. (Lawrence Livermore National Lab., CA (United States))

1991-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Inertially confined fusion using heavy ion drivers  

Science Conference Proceedings (OSTI)

The various technical issues of HIF will be briefly reviewed in this paper. It will be seen that there are numerous areas in common in all the approaches to HIF. In the recent International Symposium on Heavy Ion Inertial Fusion, the attendees met in specialized workshop sessions to consider the needs for research in each area. Each of the workshop groups considered the key questions of this report: (1) Is this an appropriate time for international collaboration in HIF? (2) Which problems are most appropriate for such collaboration? (3) Can the sharing of target design information be set aside until other driver and systems issues are better resolved, by which time it might be supposed that there could be a relaxation of classification of target issues? (4) What form(s) of collaboration are most appropriate, e.g., bilateral or multilateral? (5) Can international collaboration be sensibly attempted without significant increases in funding for HIF? The authors of this report share the conviction that collaboration on a broad scale is mandatory for HIF to have the resources, both financial and personnel, to progress to a demonstration experiment. Ultimately it may be possible for a single driver with the energy, power, focusibility, and pulse shape to satisfy the needs of the international community for target physics research. Such a facility could service multiple experimental chambers with a variety of beam geometries and target concepts.

Herrmannsfeldt, W.B. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Bangerter, R.O. [Lawrence Berkeley Lab., CA (United States); Bock, R. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Hogan, W.J.; Lindl, J.D. [Lawrence Livermore National Lab., CA (United States)

1991-10-01T23:59:59.000Z

102

Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver  

DOE Green Energy (OSTI)

Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 45 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

L.R. Grisham, S.K. Hahto, S.T. Hahto, J.W. Kwan, and K.N. Leung

2004-06-16T23:59:59.000Z

103

Proceedings of RIKEN BNL Research Center Workshop: Brookhaven Summer Program on Quarkonium Production in Elementary and Heavy Ion Collisions  

Science Conference Proceedings (OSTI)

Understanding the structure of the hadron is of fundamental importance in subatomic physics. Production of heavy quarkonia is arguably one of the most fascinating subjects in strong interaction physics. It offers unique perspectives into the formation of QCD bound states. Heavy quarkonia are among the most studied particles both theoretically and experimentally. They have been, and continue to be, the focus of measurements in all high energy colliders around the world. Because of their distinct multiple mass scales, heavy quarkonia were suggested as a probe of the hot quark-gluon matter produced in heavy-ion collisions; and their production has been one of the main subjects of the experimental heavy-ion programs at the SPS and RHIC. However, since the discovery of J/psi at Brookhaven National Laboratory and SLAC National Accelerator Laboratory over 36 years ago, theorists still have not been able to fully understand the production mechanism of heavy quarkonia, although major progresses have been made in recent years. With this in mind, a two-week program on quarkonium production was organized at BNL on June 6-17, 2011. Many new experimental data from LHC and from RHIC were presented during the program, including results from the LHC heavy ion run. To analyze and correctly interpret these measurements, and in order to quantify properties of the hot matter produced in heavy-ion collisions, it is necessary to improve our theoretical understanding of quarkonium production. Therefore, a wide range of theoretical aspects on the production mechanism in the vacuum as well as in cold nuclear and hot quark-gluon medium were discussed during the program from the controlled calculations in QCD and its effective theories such as NRQCD to various models, and to the first principle lattice calculation. The scientific program was divided into three major scientific parts: basic production mechanism for heavy quarkonium in vacuum or in high energy elementary collisions; the formation of quarkonium in nuclear medium as well as the strong interacting quark-gluon matter produced in heavy ion collisions; and heavy quarkonium properties from the first principle lattice calculations. The heavy quarkonium production at a future Electron-Ion Collider (EIC) was also discussed at the meeting. The highlight of the meeting was the apparent success of the NRQCD approach at next-to-leading order in the description of the quarkonium production in proton-proton, electron-proton and electron positron collisions. Still many questions remain open in lattice calculations of in-medium quarkonium properties and in the area of cold nuclear matter effects.

Dumitru, A.; Lourenco, C.; Petreczky, P.; Qiu, J., Ruan, L.

2011-08-03T23:59:59.000Z

104

The Heavy Ion Fusion Science Virtual National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Slide 1 The Heavy Ion Fusion Science Virtual National Laboratory Python in a Parallel Environment Dave Grote - LLNL & LBNL NUG2013 User Day Wednesday, February 15, 2013 Slide 2 The...

105

Heavy-ion Accelerators for Testing Microelectronic Components at LBNL |  

Office of Science (SC) Website

Heavy-ion Accelerators for Testing Heavy-ion Accelerators for Testing Microelectronic Components at LBNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Heavy-ion Accelerators for Testing Microelectronic Components at LBNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Use of heavy-ion accelerators for testing microelectronic components for

106

A new luminescence beam profile monitor for intense proton and heavy ion beams  

DOE Green Energy (OSTI)

A new luminescence beam profile monitor is realized in the polarized hydrogen gas jet target at the Relativistic Heavy Ion Collider (RHIC) facility. In addition to the spin polarization of the proton beam being routinely measured by the hydrogen gas jet, the luminescence produced by beam-hydrogen excitation leads to a strong Balmer series lines emission. A selected hydrogen Balmer line is spectrally filtered and imaged to produce the transverse RHIC proton beam shape with unprecedented details on the RHIC beam profile. Alternatively, when the passage of the high energy RHIC gold ion beam excited only the residual gas molecules in the beam path, sufficient ion beam induced luminescence is produced and the transverse gold ion beam profile is obtained. The measured transverse beam sizes and the calculated emittances provide an independent confirmation of the RHIC beam characteristics and to verify the emittance conservation along the RHIC accelerator. This optical beam diagnostic technique by making use of the beam induced fluorescence from injected or residual gas offers a truly noninvasive particle beam characterization, and provides a visual observation of proton and heavy ion beams. Combined with a longitudinal bunch measurement system, a 3-dimensional spatial particle beam profile can be reconstructed tomographically.

Tsang,T.; Bellavia, S.; Connolly, R.; Gassner, D.; Makdisi, Y.; Russo, T.; Thieberger, P.; Trbojevic, D.; Zelenski, A.

2008-10-01T23:59:59.000Z

107

THEORETICAL PROGRESS FOR THE ASSOCIATED PRODUCTION OF A HIGGS BOSON WITH HEAVY QUARKS AT HADRON COLLIDERS.  

SciTech Connect

The production of a Higgs boson in association with a pair of t{bar t} or b{bar b} quarks plays a very important role at both the Tevatron and the Large Hadron Collider. The theoretical prediction of the corresponding cross sections has been improved by including the complete next-to-leading order QCD corrections. After a brief introduction, we review the results obtained for both the Tevatron and the Large Hadron Collider.

DAWSON,S.JACKSON,C.B.ORR,L.H.REINA,L.WACKEROTH,D.

2003-07-17T23:59:59.000Z

108

NUCLEAR STRUCTURE AND HEAVY-ION FUSION  

E-Print Network (OSTI)

Nuclear Structure and Heavy-Ton Fusion* A series of lecturesthe cross section for fusion in the experiments consideredEffects g in III. Subharrier Fusion Cross Sections for Light

Stokstad, R.G.

2010-01-01T23:59:59.000Z

109

Nuclear physics with a medium-energy Electron-Ion Collider  

E-Print Network (OSTI)

A polarized ep/eA collider (Electron-Ion Collider, or EIC) with variable center-of-mass energy sqrt(s) ~ 20-70 GeV and a luminosity ~ 10^{34} cm^{-2} s^{-1} would be uniquely suited to address several outstanding questions of Quantum Chromodynamics (QCD) and the microscopic structure of hadrons and nuclei: (i) the three-dimensional structure of the nucleon in QCD (sea quark and gluon spatial distributions, orbital motion, polarization, correlations); (ii) the fundamental color fields in nuclei (nuclear parton densities, shadowing, coherence effects, color transparency); (iii) the conversion of color charge to hadrons (fragmentation, parton propagation through matter, in-medium jets). We briefly review the conceptual aspects of these questions and the measurements that would address them, emphasizing the qualitatively new information that could be obtained with the collider. Such a medium-energy EIC could be realized at Jefferson Lab after the 12 GeV Upgrade (MEIC), or at Brookhaven National Lab as the low-energy stage of eRHIC.

A. Accardi; V. Guzey; A. Prokudin; C. Weiss

2011-10-05T23:59:59.000Z

110

Nuclear physics with a medium-energy Electron-Ion Collider  

Science Conference Proceedings (OSTI)

A polarized ep/eA collider (Electron-Ion Collider, or EIC) with variable center-of-mass energy {radical}s {approx} 20-70 GeV and a luminosity {approx}10{sup 34} cm{sup -2} s{sup -1} would be uniquely suited to address several outstanding questions of Quantum Chromodynamics (QCD) and the microscopic structure of hadrons and nuclei: (i) the three-dimensional structure of the nucleon in QCD (sea quark and gluon spatial distributions, orbital motion, polarization, correlations); (ii) the fundamental color fields in nuclei (nuclear parton densities, shadowing, coherence effects, color transparency); (iii) the conversion of color charge to hadrons (fragmentation, parton propagation through matter, in-medium jets). We briefly review the conceptual aspects of these questions and the measurements that would address them, emphasizing the qualitatively new information that could be obtained with the collider. Such a medium-energy EIC could be realized at Jefferson Lab after the 12 GeV Upgrade (MEIC), or at Brookhaven National Lab as the low-energy stage of eRHIC.

A. Accardi, V. Guzey, A. Prokudin, C. Weiss

2012-06-01T23:59:59.000Z

111

RECENT PROGRESS IN HEAVY ION SOURCES  

E-Print Network (OSTI)

improved Bevalac Fusion reactors Vi Q) U .c. Laser, expl.into thermonuclear fusion reactors. A summary of ion sources

Clark, D.J.

2010-01-01T23:59:59.000Z

112

Molecular dynamics simulations of ion range profiles for heavy ions in light targets  

SciTech Connect

The determination of stopping powers for slow heavy ions in targets containing light elements is important to accurately describe ionsolid interactions, evaluate ion irradiation effects and predict ion ranges for device fabrication and nuclear applications. Recently, discrepancies of up to 40% between the experimental results and SRIM (Stopping and Range of Ions in Matter) predictions of ion ranges for heavy ions with medium and low energies (ion ranges indicate that the stopping powers used in the SRIM code are overestimated. Here, a molecular dynamics simulation scheme is developed to calculate the ion ranges of heavy ions in light elemental targets. Electronic stopping powers generated from both a reciprocity approach and the SRIM code are used to investigate the influence of electronic stopping on ion range profiles. The ion range profiles for Au and Pb ions in SiC and Er ions in Si, with energies between 20 and 5250 keV, are simulated. The simulation results show that the depth profiles of implanted ions are deeper and in better agreement with the experiments when using the electronic stopping power values derived from the reciprocity approach. These results indicate that the origin of the discrepancy in ion ranges between experimental results and SRIM predictions in the low energy region may be an overestimation of the electronic stopping powers used in SRIM.

Lan, C.; Xue, J. M.; Zhang, Y.; Morris, J. R.; Zhu, Zh.; Gao, Yanfei; Wang, Y. G.; Yan, S.; Weber, William

2012-01-01T23:59:59.000Z

113

Molecular dynamics simulations of ion range profiles for heavy ions in light targets  

SciTech Connect

The determination of stopping powers for slow heavy ions in targets containing light elements is important to accurately describe ion-solid interactions, evaluate ion irradiation effects and predict ion ranges for device fabrication and nuclear applications. Recently, discrepancies of up to 40% between the experimental results and SRIM (Stopping and Range of Ions in Matter) predictions of ion ranges for heavy ions with medium and low energies (< {approx} 25 keV/nucleon) in light elemental targets have been reported. The longer experimental ion ranges indicate that the stopping powers used in the SRIM code are overestimated. Here, a molecular dynamics simulation scheme is developed to calculate the ion ranges of heavy ions in light elemental targets. Electronic stopping powers generated from both a reciprocity approach and the SRIM code are used to investigate the influence of electronic stopping on ion range profiles. The ion range profiles for Au and Pb ions in SiC and Er ions in Si, with energies between 20 and 5250 keV, are simulated. The simulation results show that the depth profiles of implanted ions are deeper and in better agreement with the experiments when using the electronic stopping power values derived from the reciprocity approach. These results indicate that the origin of the discrepancy in ion ranges between experimental results and SRIM predictions in the low energy region may be an overestimation of the electronic stopping powers used in SRIM.

Lan, Chune [Peking University; Xue, Jianming [Peking University; Zhang, Yanwen [ORNL; Morris, James R [ORNL; Zhu, Zihua [Pacific Northwest National Laboratory (PNNL); Gao, Yuan [Peking University; Wang, Yugang [Peking University; Yan, Sha [Peking University; Weber, William J [ORNL

2012-01-01T23:59:59.000Z

114

Molecular dynamics simulations of ion range profiles for heavy ions in light targets  

SciTech Connect

The determination of stopping powers for slow heavy ions in targets containing light elements is important to accurately describe ion-solid interactions, evaluate ion irradiation effects and predict ion ranges for device fabrication and nuclear applications. Recently, discrepancies of up to 40% between the experimental results and SRIM (Stopping and Range of Ions in Matter) predictions of ion ranges for heavy ions with medium and low energies (<25 keV/nucleon) in light elemental targets have been reported. The longer experimental ion ranges indicate that the stopping powers used in the SRIM code are overestimated. Here, a molecular dynamics simulation scheme is developed to calculate the ion ranges of heavy ions in light elemental targets. Electronic stopping powers generated from both a reciprocity approach and the SRIM code are used to investigate the influence of electronic stopping on ion range profiles. The ion range profiles for Au and Pb ions in SiC and Er ions in Si, with energies between 20 and 5250 keV, are simulated. The simulation results show that the depth profiles of implanted ions are deeper and in better agreement with the experiments when using the electronic stopping power values derived from the reciprocity approach. These results indicate that the origin of the discrepancy in ion ranges between experimental results and SRIM predictions in the low energy region may be an overestimation of the electronic stopping powers used in SRIM.

Lan, Chune; Xue, Jianming; Zhang, Yanwen; Morris, James R.; Zhu, Zihua; Gao, Yuan; Wang, Yugang; Yan, Sha; Weber, William J.

2012-09-01T23:59:59.000Z

115

THE DEVELOPMENT OF HEAVY-ION ACCELERATORS AS DRIVERS FOR INERTIALLY CONFINED FUSION  

E-Print Network (OSTI)

29 The Fission-fusion Hybrid - iii - General DiscussionInteraction in Heavy Ion Fusion BIBLIOGRAPHY HEAVY IONReactor Designs . . . 27 Pure Fusion Power Reactor Tritium

Herrmannsfeldt, W.b.

2010-01-01T23:59:59.000Z

116

Inertial Fusion Driven by Intense Heavy-Ion Beams  

NLE Websites -- All DOE Office Websites (Extended Search)

INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS * W. M. Sharp # , A. Friedman, D. P. Grote, J. J. Barnard, R. H. Cohen, M. A. Dorf, S. M. Lund, L. J. Perkins, M. R. Terry, LLNL, Livermore, CA, USA B. G. Logan, F. M. Bieniosek, A. Faltens, E. Henestroza, J.-Y. Jung, J. W. Kwan, E. P. Lee, S. M. Lidia, P. A. Ni, L. L. Reginato, P. K. Roy, P. A. Seidl, J. H. Takakuwa, J.-L. Vay, W. L. Waldron, LBNL, Berkeley, CA, USA R. C. Davidson, E. P. Gilson, I. D. Kaganovich, H. Qin, E. Startsev, PPPL, Princeton, NJ, USA I. Haber, R. A. Kishek, University of Maryland, College Park, MD, USA A. E. Koniges, NERSC, Berkeley, CA, USA Abstract Intense heavy-ion beams have long been considered a promising driver option for inertial-fusion energy production. This paper briefly compares inertial

117

Heavy ion radiation damage simulations for CMOS image sensors Henok Mebrahtua  

E-Print Network (OSTI)

Heavy ion radiation damage simulations for CMOS image sensors Henok Mebrahtua , Wei Gaoa , Paul J, University of Toronto, Toronto, Ontario, Canada ABSTRACT Damage in CMOS image sensors caused by heavy ions and range of ions in matter) simulation results of heavy ion radiation damage to CMOS image sensors

Hornsey, Richard

118

QCD plasma instability and thermalisation at heavy ion collisions  

E-Print Network (OSTI)

Under suitable non-equilibrium conditions QCD plasma can develop plasma instabilities, where some modes of the plasma grow exponentially. It has been argued that these instabilities can play a significant role in the thermalisation of the plasma in heavy-ion collision experiments. We study the instability in SU(2) plasmas using the hard thermal loop effective lattice theory, which is suitable for studying real-time evolution of long wavelength modes in the plasma. We observe that under suitable conditions the plasma can indeed develop an instability which can grow to a very large magnitude, necessary for the rapid thermalisation in heavy-ion collisions.

Dietrich Bodeker; Kari Rummukainen

2007-11-13T23:59:59.000Z

119

Relativistic hydrodynamics, heavy ion reactions and antiproton annihilation  

SciTech Connect

The application of relativistic hydrodynamics to relativistic heavy ions and antiproton annihilation is summarized. Conditions for validity of hydrodynamics are presented. Theoretical results for inclusive particle spectra, pion production and flow analysis are given for medium energy heavy ions. The two-fluid model is introduced and results presented for reactions from 800 MeV per nucleon to 15 GeV on 15 GeV per nucleon. Temperatures and densities attained in antiproton annihilation are given. Finally, signals which might indicate the presence of a quark-gluon plasma are briefly surveyed.

Strottman, D.

1985-01-01T23:59:59.000Z

120

Heating of heavy ions on auroral field lines  

DOE Green Energy (OSTI)

Heating of heavy ions is studied in the presence of large amplitude hydrogen cyclotron waves. A three wave decay process, in which a large amplitude pump hydrogen cyclotron wave decays into a daughter hydrogen cyclotron wave and a low frequency oxygen cyclotron wave, is studied theoretically and by numerical simulations. The numerical simulations show a decay instability resulting in strong heating of both the oxygen ions and the hydrogen ions. In particular, the high energy tail of the oxygen ions is observed in the perpendicular distribution.

Nishikawa, K.I.; Okuda, H., Hasegawa, A.

1983-01-01T23:59:59.000Z

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121

Benchmarking Heavy Ion Transport Codes FLUKA, HETC-HEDS MARS15, MCNPX, and PHITS  

Science Conference Proceedings (OSTI)

Powerful accelerators such as spallation neutron sources, muon-collider/neutrino facilities, and rare isotope beam facilities must be designed with the consideration that they handle the beam power reliably and safely, and they must be optimized to yield maximum performance relative to their design requirements. The simulation codes used for design purposes must produce reliable results. If not, component and facility designs can become costly, have limited lifetime and usefulness, and could even be unsafe. The objective of this proposal is to assess the performance of the currently available codes â?? PHITS, FLUKA, MARS15, MCNPX, and HETC-HEDS â?? that could be used for design simulations involving heavy ion transport. We plan to access their performance by performing simulations and comparing results against experimental data of benchmark quality. Quantitative knowledge of the biases and the uncertainties of the simulations is essential as this potentially impacts the safe, reliable and cost effective design of any future radioactive ion beam facility. Further benchmarking of heavy-ion transport codes was one of the actions recommended in the â??Report of the 2003 RIA R&D Workshop".

Ronningen, Reginald Martin [Michigan State University; Remec, Igor [Oak Ridge National Laboratory; Heilbronn, Lawrence H. [University of Tennessee-Knoxville

2013-06-07T23:59:59.000Z

122

EBIS as an injector for heavy-ion linacs  

SciTech Connect

The Electron Beam Ion Source (EBIS), because of its high-charge states and pulsed operation, is ideally suited as an injector for a heavy-ion linac operating at a low duty factor. Although presently in use with conventional linacs, the low emittance and the large yield of highly charged ions in each pulse make the EBIS even more interesting as an injector for the new linac accelerating structures such as the alternating-phase-focusing (APF) structure or the radio-frequency quadrupole (RFQ) structure. These new structures could be used with an EBIS to produce a small, efficient, low-duty-cycle accelerator. Coupled to a conventional linac, the resulting accelerator could be used for heavy-ion medical therapy or nuclear physics, or it could be used as an injector for a synchrotron or storage ring.

Hamm, R.W.

1979-01-01T23:59:59.000Z

123

Fragmentation of very high energy heavy ions  

E-Print Network (OSTI)

A stack of CR39 (C12H18O7)n nuclear track detectors with a Cu target was exposed to a 158 A GeV lead ion beam at the CERN-SPS, in order to study the fragmentation properties of lead nuclei. Measurements of the total, break-up and pick-up charge-changing cross sections of ultrarelativistic Pb ions on Cu and CR39 targets are presented and discussed.

Giorgini, M

2001-01-01T23:59:59.000Z

124

Final Report for Project ``Theory of ultra-relativistic heavy-ion collisions''  

SciTech Connect

In the course of this project the Ohio State University group led by the PI, Professor Ulrich Heinz, developed a comprehensive theoretical picture of the dynamical evolution of ultra-relativistic heavy-ion collisions and of the numerous experimental observables that can be used to diagnose the evolving and short-lived hot and dense fireball created in such collisions. Starting from a qualitative understanding of the main features based on earlier research during the last decade of the twentieth century on collisions at lower energies, the group exploited newly developed theoretical tools and the stream of new high-quality data from the Relativistic Heavy Ion Collider at Brookhaven National Laboratory (which started operations in the summer of the year 2000) to arrive at an increasingly quantitative description of the experimentally observed phenomena. Work done at Ohio State University (OSU) was instrumental in the discovery during the years 2001-2003 that quark-gluon plasma (QGP) created in nuclear collisions at RHIC behaves like an almost perfect liquid with minimal viscosity. The tool of relativistic fluid dynamics for viscous liquids developed at OSU in the years 2005-2007 opened the possibility to quantitatively determine the value of the QGP viscosity empirically from experimental measurements of the collective flow patterns established in the collisions. A first quantitative extraction of the QGP shear viscosity, with controlled theoretical uncertainty estimates, was achieved during the last year of this project in 2010. OSU has paved the way for a transition of the field of relativistic heavy-ion physics from a qualitative discovery stage to a new stage of quantitative precision in the description of quark-gluon plasma properties. To gain confidence in the precision of our theoretical understanding of quark-gluon plasma dynamics, one must test it on a large set of experimentally measured observables. This achievement report demonstrates that we have, at different times, systematically investigated both so-called ``soft" and ``hard, penetrating" probes of the fireball medium: hadron yields and momentum spectra and their anisotropies, two-particle momentum correlations, high-energy partons fragmenting into jets, heavy quarks and heavy-flavor mesons, and electromagnetic probes (photons and dileptons). Our strongest emphasis, and our most significant achievements, has, however, always remained on understanding the bulk behavior of the heavy-ion fireball medium, for which soft probes provide the most abundantly available data and thus the most stringent constraints.

Ulrich W. Heinz

2012-11-09T23:59:59.000Z

125

Direct photons ~basis for characterizing heavy ion collisions~  

E-Print Network (OSTI)

After years of experimental and theoretical efforts, direct photons become a strong and reliable tool to establish the basic characteristics of a hot and dense matter produced in heavy ion collisions. The recent direct photon measurements are reviewed and a future prospect is given.

Takao Sakaguchi

2008-05-30T23:59:59.000Z

126

Chemical Equilibrium in Heavy Ion Collisions: Rapidity Dependence  

E-Print Network (OSTI)

Particle yields in heavy ion collisions show an overwhelming evidence for chemical or relative chemical equilibrium at all beam energies. The rapidity dependence of the thermal parameters $T$ and $\\mu_B$ can now be determined over a wide range of rapidities and show a systematic behavior towards an increase in $\\mu_B$ away from mid-rapidity.

F. Becattini; J. Cleymans

2007-01-04T23:59:59.000Z

127

Spatially resolved instability measurements with a heavy ion beam probe  

SciTech Connect

A heavy ion beam probe was used to make simultaneous measurements of the amplitude and phase of both density and space potential fluctuations in an energetic arc plasma. Detailed comparison with theoretical predictions identifies a 70 KHz coherent oscillation as a Kelvin-Helmholtz instability localized to a region of strong fluid shear. (auth)

Jennings, W. C.; Hickok, R. L.; Glowienka, J. C.

1975-01-01T23:59:59.000Z

128

Multiplicity Dependence of Partially Coherent Pion Production in Relativistic Heavy Ion Collisions  

E-Print Network (OSTI)

We investigate two- and three-particle intensity correlation functions of pions in relativistic heavy ion collisions for different colliding energies. Based on three models of particle production, we analyze the degree to which the pion sources are chaotic in the SPS S+Pb, Pb+Pb and the RHIC Au+Au collisions. The ``chaoticity'', $\\lambda$, of the two-particle correlation functions is corrected for long-lived resonance decays. The effect of the partial Coulomb correction is also examined. Although the partially coherent model gives a result which is consistent with that of STAR, the chaotic fraction does not exhibit clear multiplicity dependence if we take into account both the corrected chaoticity and the weight factor of the three-pion correlation function. The result of the partially-multicoherent model indicates an increasing number of coherent sources in higher multiplicity events.

Kenji Morita; Shin Muroya; Hiroki Nakamura

2006-02-04T23:59:59.000Z

129

Heavy-Ion-Fusion-Science: Summary of U.S. Progress  

E-Print Network (OSTI)

IAEA-06 Topic IF Heavy-Ion-Fusion-Science: Summary of U.S.W.L. Waldron, U.S. Heavy Ion Fusion Science Virtual NationalExperiment at PPPL. [1] Fusion Energy Sciences Advisory

2006-01-01T23:59:59.000Z

130

HEAVY ION FUSION YEAR-END REPORT APRIL 1, 1981 - SEPT. 30, 1981  

E-Print Network (OSTI)

Keefe E. Denis Keefe HEAVY ION FUSION ROSTER Warren W. ChuppOF CALIFORNIA Accelerator & Fusion Research DivisionHEAVY ION FUSION YEAR-END REPORT April 1, 1981 - September

Authors, Various

2010-01-01T23:59:59.000Z

131

LAWRENCE BERKELEY LABORATORY YEAR-END-REPORT ON HEAVY-ION FUSION PROGRAM  

E-Print Network (OSTI)

Beams of a Pellet Fusion Reactor by D. Neuffer, GeometricTarget of a Heavy Ion Fusion Reactor: Summary of a meetingTarget of a Heavy Ion Fusion Reactor: Summary of a Meeting

Staff, HIF

2011-01-01T23:59:59.000Z

132

Workshop on Accelerators for Heavy Ion Fusion Summary Report of the Workshop  

E-Print Network (OSTI)

W. M. Sharp, and D. R. Welch, Fusion Sci. Technol. 44, 266implosion in heavy ion fusion,"Laser Part. Beam 24, 359-Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency.

Seidl, P.A.

2013-01-01T23:59:59.000Z

133

Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all  

E-Print Network (OSTI)

This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them, and it benefited from inputs from the users' communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the U.S., established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.

A. Accardi; J. L. Albacete; M. Anselmino; N. Armesto; E. C. Aschenauer; A. Bacchetta; D. Boer; W. Brooks; T. Burton; N. -B. Chang; W. -T. Deng; A. Deshpande; M. Diehl; A. Dumitru; R. Dupr; R. Ent; S. Fazio; H. Gao; V. Guzey; H. Hakobyan; Y. Hao; D. Hasch; R. Holt; T. Horn; M. Huang; A. Hutton; C. Hyde; J. Jalilian-Marian; S. Klein; B. Kopeliovich; Y. Kovchegov; K. Kumar; K. Kumeri?ki; M. A. C. Lamont; T. Lappi; J. -H. Lee; Y. Lee; E. M. Levin; F. -L. Lin; V. Litvinenko; T. W. Ludlam; C. Marquet; Z. -E. Meziani; R. McKeown; A. Metz; R. Milner; V. S. Morozov; A. H. Mueller; B. Mller; D. Mller; P. Nadel-Turonski; A. Prokudin; V. Ptitsyn; X. Qian; J. -W. Qiu; M. Ramsey-Musolf; T. Roser; F. Sabati; R. Sassot; G. Schnell; P. Schweitzer; E. Sichtermann; M. Stratmann; M. Strikman; M. Sullivan; S. Taneja; T. Toll; D. Trbojevic; T. Ullrich; R. Venugopalan; S. Vigdor; W. Vogelsang; C. Weiss; B. -W. Xiao; F. Yuan; Y. -H. Zhang; L. Zheng

2012-12-07T23:59:59.000Z

134

The ALICE Photo Gallery: Images from A Large Ion Collider Experiment (ALICE) at CERN  

DOE Data Explorer (OSTI)

ALICE is the acronym for A Large Ion Collider Experiment, one of the largest experiments in the world devoted to research in the physics of matter at an infinitely small scale. Hosted at CERN, the European Laboratory for Nuclear Research, this project involves an international collaboration of more than 1000 physicists, engineers and technicians, including around 200 graduate students, from 105 physics institutes in 30 countries across the world. The ALICE Experiment is going in search of answers to fundamental questions, using the extraordinary tools provided by the Large Hadron Collider (LHC): 1) What happens to matter when it is heated to 100,000 times the temperature at the centre of the Sun? 2) Why do protons and neutrons weigh 100 times more than the quarks they are made of? 3) Can the quarks inside the protons and neutrons be freed? [copied from http://aliceinfo.cern.ch/Public/Welcome.html]

The Alice Photo Gallery highlights images taken by three professional photographers, Pavel Cugini, Peter Ginter, and Antonio Saba. Other pictures can be found in the Cern Document Server Database at http://cdsweb.cern.ch/.

Cugini, Pavel; Ginter, Peter; Saba, Antonio

135

Means for obtaining a metal ion beam from a heavy-ion cyclotron source  

DOE Patents (OSTI)

A description is given of a modification to a cyclotron ion source used in producing a high intensity metal ion beam. A small amount of an inert support gas maintains the usual plasma arc, except that it is necessary for the support gas to have a heavy mass, e.g., xenon or krypton as opposed to neon. A plate, fabricated from the metal (or anything that can be sputtered) to be ionized, is mounted on the back wall of the ion source arc chamber and is bombarded by returning energetic low-charged gas ions that fail to cross the initial accelerating gap between the ion source and the accelerating electrode. Some of the atoms that are dislodged from the plate by the returning gas ions become ionized and are extracted as a useful beam of heavy ions. (auth)

Hudson, E.D.; Mallory, M.L.

1975-08-01T23:59:59.000Z

136

Collider-Accelerator Department  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Tunnel and Magnets RHIC Tunnel and Magnets RHIC Tunnel and Magnets AGS Tunnel and Magnets NSRL Beamline RF Kicker Snake 200-MeV LINAC AGS Cold Snake Magnet About the Collider-Accelerator Department The mission of the Collider-Accelerator Department is to develop, improve and operate the suite of particle / heavy ion accelerators used to carry out the program of accelerator-based experiments at BNL; to support the experimental program including design, construction and operation of the beam transports to the experiments plus support of detector and research needs of the experiments; to design and construct new accelerator facilities in support of the BNL and national missions. The C-A Department supports an international user community of over 1500 scientists. The department performs all these functions in an environmentally responsible and safe manner under a rigorous conduct of operations approach.

137

The ECR heavy-ion source for ATLAS  

SciTech Connect

The ATLAS PII-ECR ion source is the first ECR ion source to be designed for operation in a high voltage platform. The source system is required to provide beams of heavy ions with a velocity of 0.01c for subsequent acceleration by the superconducting ATLAS Positive Ion Injector Linac. At present, the ability of the system to provide high charge state ions with velocities up to .01c is probably unique and as such has generated significant interest in the atomic physics community. A beamline for atomic physics has been installed and is now in use. The source began operation in October, 1987. The source capabilities and operating experiences to date will be discussed. 6 refs., 3 figs., 3 tabs.

Pardo, R.C.; Billquist, P.J.

1989-01-01T23:59:59.000Z

138

Light-ion production from intermediate-energy Heavy-Ion interactions  

Science Conference Proceedings (OSTI)

The production of light ions such as protons, neutrons, deuterons, tritons, 3He and 4He from heavy ion interactions still remains as a key issue to be investigated for the purposes of radiation protection in space. Ultimately, we will produce double-differential ...

L. Heilbronn; M. Beach; L. Townsend

2011-03-01T23:59:59.000Z

139

Microscopic track structure of equal-LET heavy ions  

SciTech Connect

The spatial distributions of ionization and energy deposition produced by heavy (HZE) ions are crucial to an understanding of their radiation quality as exhibited eg., in track segment experiments of cell survival and chromosome aberrations of mammalian cells. The stopping power (or LET) of a high velocity ion is proportional to the ratio Z**2/v**2, apart from a slowly varying logarithmic factor. The maximum delta-ray energy that an ion can produce is proportional to v**2 (non-relativistically). Therefore, two HZE ions having the same LET, but in general differing Z and v will have different maximum delta-ray energies and consequently will produce different spatial patterns of energy deposition along their paths. To begin to explore the implications of this fact for the microscopic dosimetry of heavy ions, we have calculated radial distributions in energy imparted and ionization for iron and neon ions of approximately equal LET in order to make a direct comparison of their delta-ray track structure. Monte Carlo techniques are used for the charged particle radiation transport simulation. 10 refs., 8 figs.

Wilson, W.E.; Criswell, T.L.

1986-07-01T23:59:59.000Z

140

Heavy Flavor at the Large Hadron Collider in a Strong Coupling Approach  

E-Print Network (OSTI)

Employing nonperturbative transport coefficients for heavy-flavor (HF) diffusion through quark-gluon plasma (QGP), hadronization and hadronic matter, we compute $D$- and $B$-meson observables in Pb+Pb ($\\sqrt{s}$=2.76\\,TeV) collisions at the LHC. Elastic heavy-quark scattering in the QGP is evaluated within a thermodynamic $T$-matrix approach, generating resonances close to the critical temperature which are utilized for recombination into $D$ and $B$ mesons, followed by hadronic diffusion using effective hadronic scattering amplitudes. The transport coefficients are implemented via Fokker-Planck Langevin dynamics within hydrodynamic simulations of the bulk medium in nuclear collisions. The hydro expansion is quantitatively constrained by transverse-momentum spectra and elliptic flow of light hadrons. Our approach thus incorporates the paradigm of a strongly coupled medium in both bulk and HF dynamics throughout the thermal evolution of the system.

Min He; Rainer J. Fries; Ralf Rapp

2014-01-16T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Analytical Proton Transfer Amplitude for Heavy Ion Induced Nuclear Reactions  

Science Conference Proceedings (OSTI)

Direct reactions between heavy ions have been studied widely using semi-classical theories. The Distorted Wave Born Approximation or DWBA has been extensively applied to analyse transfer reaction processes. Initial attempts to gain insights into the simple semi-classical parametrisation starting from the DWBA had focused mainly on neutron transfer reactions. An analytical formula for the semi-classical amplitude for the transfer of a single neutron between bound classical orbits states in heavy ion collisions that agrees well with the DWBA calculations has been successfully derived. In this paper, we have successfully derived the corresponding analytical expression for the proton transfer amplitude by using a technique analogous to the transfer of a single neutron between bound states. Our result reduces to the well known expression for the neutron transfer amplitude in the limit that the nuclear charge tends to zero.

Kumar, P. Rajesh [Open University Malaysia, Jalan Tun Ismail, 50480 Kuala Lumpur (Malaysia); Wong, Bernardine Renaldo [Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2011-03-30T23:59:59.000Z

142

Kaon production in heavy ion reactions at intermediate energies  

E-Print Network (OSTI)

The article reviews the physics related to kaon and antikaon production in heavy ion reactions at intermediate energies. Chiral dynamics predicts substantial modifications of the kaon properties in a dense nuclear environment. The status of the theoretical predictions as well as experimental evidences for medium effects such as repulsive/attractive mass shifts for $K^+/K^-$ are reviewed. In the vicinity of the thresholds, and even more pronounced below threshold, the production of strangeness is a highly collective process. Starting from elementary reaction channels the phenomenology of $K^+$ and $K^-$ production, i.e. freeze-out densities, time scales etc. as derived from experiment and theoretical transport calculations is presented. Below threshold kaon production shows a high sensitivity on the nuclear compression reached in heavy ion reactions. This allows to put constraints on the nuclear equation-of-state which are finally discussed.

Christian Fuchs

2005-07-07T23:59:59.000Z

143

Triggering on hard probes in heavy ion collisions with CMS  

E-Print Network (OSTI)

We present a study of the CMS trigger system in heavy-ion collisions. Concentrating on two physics channels, dimuons from decays of quarkonia and single jets, we evaluate a possible trigger strategy for Pb+Pb running that relies on event selection solely in the High-Level Trigger (HLT). The study is based on measurements of the timing performance of the offline algorithms and event-size distributions using full simulations. Using a trigger simulation chain, we compare the physics reach for the jet and dimuon channels using online selection in the HLT to minimum bias running. The results demonstrate the crucial role the HLT will play for CMS heavy-ion physics.

G. Roland; for the CMS Collaboration

2007-02-21T23:59:59.000Z

144

Heavy-ion accelerator research for inertial fusion  

SciTech Connect

Thermonuclear fusion offers a most attractive long-term solution to the problem of future energy supplies: The fuel is virtually inexhaustible and the fusion reaction is notably free of long-lived radioactive by-products. Also, because the fuel is in the form of a plasma, there is no solid fuel core that could melt down. The DOE supports two major fusion research programs to exploit these virtues, one based on magnetic confinement and a second on inertial confinement. One part of the program aimed at inertial fusion is known as Heavy Ion Fusion Accelerator Research, or HIFAR. In this booklet, the aim is to place this effort in the context of fusion research generally, to review the brief history of heavy-ion fusion, and to describe the current status of the HIFAR program.

1987-08-01T23:59:59.000Z

145

Accelerators for heavy ion inertial fusion: Progress and plans  

SciTech Connect

The Heavy Ion Inertial Fusion Program is the principal part of the Inertial Fusion Energy Program in the Office of Fusion Energy of the U.S. Department of Energy. The emphasis of the Heavy Ion Program is the development of accelerators for fusion power production. Target physics research and some elements of fusion chamber development are supported in the much larger Inertial Confinement Fusion Program, a dual purpose (defense and energy) program in the Defense Programs part of the Department of Energy. The accelerator research program will establish feasibility through a sequence of scaled experiments that will demonstrate key physics and engineering issues at low cost compared to other fusion programs. This paper discusses progress in the accelerator program and outlines how the planned research will address the key economic issues of inertial fusion energy.

Bangerter, R.O.; Friedman, A.; Herrmannsfeldt, W.B.

1994-08-01T23:59:59.000Z

146

The shape of heavy ion upset cross section curves  

Science Conference Proceedings (OSTI)

An approach is developed to describe heavy ion single event upset cross section curves. It accounts for all significant mechanisms which cause the curve to deviate from ideal, step function-like behavior. The method is developed in terms of the charge deposited by an incident ion in a memory cell and is therefore free of ambiguities associated with the effective LET concept. It is suggested that this type of approach is an improvement over current methods used to characterize a memory response to accelerator tests. This has significant implications for predicting space upset rates.

Xapsos, M.A. (Naval Research Lab., Washington, DC (United States). Radiation Effects Branch); Weatherford, T.R.; Shapiro, P. (SFA, Inc., Landover, MD (United States))

1993-12-01T23:59:59.000Z

147

Single event upset testing with relativistic heavy ions  

SciTech Connect

Two bipolar devices, the AMD 2901B microprocessor and the AMD 27LS00 256-bit RAM, have been tested for single event upset using relativistic heavy ions. Upset thresholds and asymptotic cross sections have been measured with iron, argon and neon beams having cosmic ray energies. Further, the magnitude of the funnel effect in the 2901B was determined by irradiating the device at normal incidence and at large angles and comparing the observed upset thresholds. Combinatorial logic upsets were seen in the 2901B and their cross section measured. The 27LS00 exhibited multibit upset produced by single ions penetrating the device edge-on.

Criswell, T.L.; Measeal, P.R.; Walin, K.L.

1984-12-01T23:59:59.000Z

148

Limiting fragmentation of chemical potentials in heavy ion collisions  

E-Print Network (OSTI)

Thermal models have been used to successfully describe the hadron yields from heavy ion collisions at a variety of energies. For root(S)chemical potentials, muS = 0.21 +-0.01muB. Using this relation we are able to describe the energy dependence of Lambda, Xsi and Omega ratios from other experiments. We also find that the chemical potentials are consistent with limiting fragmentation.

Laura A. Stiles; Michael Murray

2006-01-30T23:59:59.000Z

149

Production of 14 MeV neutrons by heavy ions  

SciTech Connect

This invention relates to a neutron generator and a method for the production of 14 MeV neutrons. Heavy ions are accelerated to impinge upon a target mixture of deuterium and tritium to produce recoil atoms of deuterium and tritium. These recoil atoms have a sufficient energy such that they interact with other atoms of tritium or deuterium in the target mixture to produce approximately 14 MeV neutrons.

Brugger, Robert M. (Columbia, MO); Miller, Lowell G. (Idaho Falls, ID); Young, Robert C. (Idaho Falls, ID)

1977-01-01T23:59:59.000Z

150

Experimental evaluation of a negative ion source for a heavy ionfusion negative ion driver  

DOE Green Energy (OSTI)

Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photodetached to neutrals [1,2,3]. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that is used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

Grisham, L.R.; Hahto, S.K.; Hahto, S.T.; Kwan, J.W.; Leung, K.N.

2005-01-18T23:59:59.000Z

151

Optimization of muon timing and searches for heavy long-lived charged particles with the Compact Muon Solenoid detector at the Large Hadron Collider  

E-Print Network (OSTI)

Large Hadron Collider . . . . . . . . . . . . . . . . . . . . . . . .detector at the Large Hadron Collider A dissertationdetector at the Large Hadron Collider by Christopher Patrick

Farrell, Christopher Patrick

2013-01-01T23:59:59.000Z

152

Modeling Chamber Transport for Heavy-Ion Fusion  

DOE Green Energy (OSTI)

In a typical thick-liquid-wall scenario for heavy-ion fusion (HIF), between seventy and two hundred high-current beams enter the target chamber through ports and propagate about three meters to the target. Since molten-salt jets are planned to protect the chamber wall, the beams move through vapor from the jets, and collisions between beam ions and this background gas both strip the ions and ionize the gas molecules. Radiation from the preheated target causes further beam stripping and gas ionization. Due to this stripping, beams for heavy-ion fusion are expected to require substantial neutralization in a target chamber. Much recent research has, therefore, focused on beam neutralization by electron sources that were neglected in earlier simulations, including emission from walls and the target, photoionization by the target radiation, and pre-neutralization by a plasma generated along the beam path. When these effects are included in simulations with practicable beam and chamber parameters, the resulting focal spot is approximately the size required by a distributed radiator target.

Sharp, W M; Niller, D A C; Tabak, M; Yu, S S; Peterson, P F; Welch, D R; Rose, D V; Olson, C L

2002-08-02T23:59:59.000Z

153

Beam Compression in Heavy-Ion Induction Linacs  

SciTech Connect

The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the Warm Dense Matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the LBNL Neutralized Drift Compression Experiment (NDCX) experiment with controlled ramps and forced neutralization. The achieved peak beam current and energy can be used in experiments to heat targets and create warm dense matter. Using an injected 30 mA K{sup +} ion beam with initial kinetic energy 0.3 MeV, axial compression leading to {approx}50x current amplification and simultaneous radial focusing to beam radii of a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss experiments that are under development to reach the necessary higher beam intensities and the associated beam diagnostics.

Seidl, P.A.; Anders, A.; Bieniosek, F.M.; Barnard, J.J.; Calanog, J.; Chen, A.X.; Cohen, R.H.; Coleman, J.E.; Dorf, M.; Gilson, E.P.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Ni, P.; Roy, P.K.; Van den Bogert, K.; Waldron, W.L.; Welch, D.R.

2009-01-01T23:59:59.000Z

154

Measurements of phi meson production in relativistic heavy-ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC)  

E-Print Network (OSTI)

We present results for the measurement of ? meson production via its charged kaon decay channel ??K[superscript +]K[superscript -] in Au+Au collisions at ?(s[subscript NN])=62.4,130, and 200 GeV, and in p+p and d+Au ...

Sakuma, Tai

155

Glenn T. Seaborg and heavy ion nuclear science  

Science Conference Proceedings (OSTI)

Radiochemistry has played a limited but important role in the study of nucleus-nucleus collisions. Many of the important radiochemical studies have taken place in Seaborg's laboratory or in the laboratories of others who have spent time in Berkeley working with Glenn T. Seaborg. I will discuss studies of low energy deep inelastic reactions with special emphasis on charge equilibration, studies of the properties of heavy residues in intermediate energy nuclear collisions and studies of target fragmentation in relativistic and ultrarelativistic reactions. The emphasis will be on the unique information afforded by radiochemistry and the physical insight derived from radiochemical studies. Future roles of radiochemistry in heavy ion nuclear science also will be discussed.

Loveland, W. (Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry Lawrence Berkeley Lab., CA (United States))

1992-04-01T23:59:59.000Z

156

Glenn T. Seaborg and heavy ion nuclear science  

Science Conference Proceedings (OSTI)

Radiochemistry has played a limited but important role in the study of nucleus-nucleus collisions. Many of the important radiochemical studies have taken place in Seaborg`s laboratory or in the laboratories of others who have spent time in Berkeley working with Glenn T. Seaborg. I will discuss studies of low energy deep inelastic reactions with special emphasis on charge equilibration, studies of the properties of heavy residues in intermediate energy nuclear collisions and studies of target fragmentation in relativistic and ultrarelativistic reactions. The emphasis will be on the unique information afforded by radiochemistry and the physical insight derived from radiochemical studies. Future roles of radiochemistry in heavy ion nuclear science also will be discussed.

Loveland, W. [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States)

1992-04-01T23:59:59.000Z

157

System for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high (n,f) reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

Fries, D.P.; Browning, J.F.

1998-07-21T23:59:59.000Z

158

System for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

Fries, David P. (St. Petersburg, FL); Browning, James F. (Palm Harbour, FL)

1998-01-01T23:59:59.000Z

159

Method for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

Fries, David P. (St. Petersburg, FL); Browning, James F. (Palm Harbour, FL)

1999-01-01T23:59:59.000Z

160

Method for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

Fries, D.P.; Browning, J.F.

1999-02-16T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Pair Production of Heavy Quarkonium and $B_c(^*)$ Mesons at Hadron Colliders  

E-Print Network (OSTI)

We investigate the pair production of S-wave heavy quarkonium at the LHC in the color-singlet mechanism (CSM) and estimate the contribution from the gluon fragmentation process in the color-octet mechanism (COM) for comparison. With the matrix elements extracted previously in the leading order calculations, the numerical results show that the production rates are quite large for the pair production processes at the LHC. The $p_t$ distribution of double $J/\\psi$ production in the CSM is dominant over that in the COM when $p_t$ is smaller than about 8GeV. For the production of double $\\Upsilon$, the contribution of the COM is always larger than that in the CSM. The large differences in the theoretical predictions between the CSM and COM for the $p_t$ distributions in the large $p_t$ region are useful in clarifying the effects of COM on the quarkonium production. We also investigate the pair production of S-wave $B_c$ and $B_c^*$ mesons, and the measurement of these processes is useful to test the CSM and extract the LDMEs for the $B_c$ and $B_c^*$ mesons.

Rong Li; Yu-Jie Zhang; Kuang-Ta Chao

2009-03-12T23:59:59.000Z

162

Modeling heavy ion ionization loss in the MARS15 code  

E-Print Network (OSTI)

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 ultra-relativistic 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.

I. L. Rakhno; N. V. Mokhov; S. I. Striganov

2005-05-05T23:59:59.000Z

163

Induction Linac Systems Experiments for heavy ion fusion  

Science Conference Proceedings (OSTI)

The Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory propose to build at LBL the Induction Linac Systems Experiments (ILSE), the next logical step toward the eventual goal of a heavy ion induction accelerator powerful enough to implode or drive inertial confinement fusion targets. Though much smaller than a driver, ILSE will be at full driver scale in several important parameters. Nearly all accelerator components and beam manipulations required for a driver will be tested. It is expected that ILSE will be built in stages as funds and technical progress allow. The first stage, called Elise will include all of the electrostatic quadrupole focused parts of ILSE.

Herrmannsfeldt, W.B. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Bangerter, R.O. [Lawrence Berkeley Lab., CA (United States). Accelerator and Fusion Research Div.

1994-06-01T23:59:59.000Z

164

Langevin dynamics of heavy flavors in relativistic heavy-ion collisions  

E-Print Network (OSTI)

We study the stochastic dynamics of c and b quarks, produced in hard initial processes, in the hot medium created after the collision of two relativistic heavy ions. This is done through the numerical solution of the relativistic Langevin equation. The latter requires the knowledge of the friction and diffusion coefficients, whose microscopic evaluation is performed treating separately the contribution of soft and hard collisions. The evolution of the background medium is described by ideal/viscous hydrodynamics. Below the critical temperature the heavy quarks are converted into hadrons, whose semileptonic decays provide single-electron spectra to be compared with the current experimental data measured at RHIC. We focus on the nuclear modification factor R_AA and on the elliptic-flow coefficient v_2, getting, for sufficiently large p_T, a reasonable agreement.

W. M. Alberico; A. Beraudo; A. De Pace; A. Molinari; M. Monteno; M. Nardi; F. Prino

2010-09-13T23:59:59.000Z

165

Langevin dynamics of heavy flavors in relativistic heavy-ion collisions  

E-Print Network (OSTI)

We study the stochastic dynamics of c and b quarks, produced in hard initial processes, in the hot medium created after the collision of two relativistic heavy ions. This is done through the numerical solution of the relativistic Langevin equation. The latter requires the knowledge of the friction and diffusion coefficients, whose microscopic evaluation is performed treating separately the contribution of soft and hard collisions. The evolution of the background medium is described by ideal/viscous hydrodynamics. Below the critical temperature the heavy quarks are converted into hadrons, whose semileptonic decays provide single-electron spectra to be compared with the current experimental data measured at RHIC. We focus on the nuclear modification factor R_AA and on the elliptic-flow coefficient v_2, getting, for sufficiently large p_T, a reasonable agreement.

Alberico, W M; De Pace, A; Molinari, A; Monteno, M; Nardi, M; Prino, F

2011-01-01T23:59:59.000Z

166

Overview of heavy-ion fusion focus on computer simulation aspect  

E-Print Network (OSTI)

Vay Heavy-Ion Fusion Virtual National Laboratory LawrenceBerkeley National Laboratory Computer Engineering Scienceand Lawrence Livermore National Laboratories under Contract

Vay, Jean-Luc

2002-01-01T23:59:59.000Z

167

Progress in Heavy Ion Driven Target Fabrication and Injection (A24727)  

E-Print Network (OSTI)

Physics Research A 544, 34 (2005)15th International Symposium on Heavy Ion Inertial Fusion Princeton New Jersey, US, 2004999609735

Goodin, D.T.

2004-06-16T23:59:59.000Z

168

Particle-production mechanism in relativistic heavy-ion collisions  

SciTech Connect

We discuss the production of particles in relativistic heavy-ion collisions through the mechanism of massive bremsstrahlung, in which massive mesons are emitted during rapid nucleon acceleration. This mechanism is described within the framework of classical hadrodynamics for extended nucleons, corresponding to nucleons of finite size interacting with massive meson fields. This new theory provides a natural covariant microscopic approach to relativistic heavy-ion collisions that includes automatically spacetime nonlocality and retardation, nonequilibrium phenomena, interactions among all nucleons, and particle production. Inclusion of the finite nucleon size cures the difficulties with preacceleration and runaway solutions that have plagued the classical theory of self-interacting point particles. For the soft reactions that dominate nucleon-nucleon collisions, a significant fraction of the incident center-of-mass energy is radiated through massive bremsstrahlung. In the present version of the theory, this radiated energy is in the form of neutral scalar ({sigma}) and neutral vector ({omega}) mesons, which subsequently decay primarily into pions with some photons also. Additional meson fields that are known to be important from nucleon-nucleon scattering experiments should be incorporated in the future, in which case the radiated energy would also contain isovector pseudoscalar ({pi}{sup +}, {pi}{sup {minus}}, {pi}{sup 0}), isovector scalar ({delta}{sup +}, {delta}{sup {minus}}, {delta}{sup 0}), isovector vector ({rho}{sup +}, {rho}{sup {minus}}, {rho}{sup 0}), and neutral pseudoscalar ({eta}) mesons.

Bush, B.W.; Nix, J.R.

1994-07-01T23:59:59.000Z

169

Spacetime nonlocality and retardation in relativistic heavy-ion collisions  

SciTech Connect

We discuss the exact numerical solution of the classical relativistic equations of motion for a Lagrangian corresponding to point nucleons interacting with massive scalar and vector meson fields. The equations of motion contain both external retarded Lorentz forces and radiation-reaction forces; the latter involve nonlocal terms that depend upon the past history of the nucleon in addition to terms analogous to those of classical electrodynamics. The resulting microscopic many-body approach to relativistic heavy-ion collisions is manifestly Lorentz covariant and allows for nonequilibrium phenomena, interactions with correlated clusters of nucleons, and particle production. For point nucleons, the asymptotic behavior of nucleonic motion prior to the collision is exponential, with a range in proper time of approximately 0.5 fm. However, this behavior is altered by the finite nucleon size, whose effect we are currently incorporating into our equations of motion. The spacetime nonlocality and retardation that will be present in the solutions of these equations may be responsible for significant collective effects in relativstic heavy-ion collisions. 11 refs., 3 figs.

Bush, B.W.; Nix, J.R.; Sierk, A.J.

1991-01-01T23:59:59.000Z

170

SYSTEMATIC STUDIES OF HEAVY ION COLLISIONS TO SEARCH FOR QUARK-GLUON PLASMA  

SciTech Connect

This is the final technical report for DOE Outstanding Junior Investigator (OJI) Award, 'Systematic Studies of Heavy Ion Collisions to Search for Quark-Gluon Plasma', grant DE-FG02-02ER41219, Principal Investigator (PI) Fuqiang Wang. The research under the grant was divided into two phases. The first concentrated on systematic studies of soft hadron production at low transverse momentum (p{sub T}), in particular the production of (anti-)baryon and strangeness in heavy ion collisions at RHIC energies. The second concentrated on measurements of di-hadron and multi-hadron jet-correlations and investigations of medium response to jets. The research was conducted at the Relativistic Heavy-Ion Collider (RHIC) at BNL with the Solenoidal Tracker At RHIC (STAR) experiment. The total grant is $214,000. The grant established a PC farm solely used for this research. The PC farm consists of 8 nodes with a total of 16 CPUs and 3 disk servers of total 2 TB shared storage. The current balance of the grant is $19,985. The positive balance is because an initial purchase of $22,600 for the PC farm came out of the PI's start-up fund due to the lateness of the award. The PC farm is an integral part of the Purdue Physics Department's computer cluster. The grant supported two Ph.D. graduate students. Levente Molnar was supported from July 2002 to December 2003, and worked on soft hadron production. His thesis title is Systematics of Identified Particle Production in pp, d-Au and Au-Au Collisions at RHIC Energies. He graduated in 2006 and now is a Postdoctoral fellow at INFN Sezione di Bari, Italy working on the ALICE experiment at the LHC. Jason Ulery was supported from January 2004 to July 2007. His thesis title is Two- and Three-Particle Jet-Like Correlations. He defended his thesis in October 2007 and is moving to Frankfurt University, Germany to work on the ALICE experiment at the LHC. The research by this grant resulted in 7 journal publications (2 PRL, 1 PLB, 1 PRC, 2 submitted and 1 in preparation), and 14 invited talks and 10 contributed talks at major conferences. These are listed at end of this report.

Fuqiang Wang

2007-11-29T23:59:59.000Z

171

Recent results in relativistic heavy ion collisions: from ``a new state of matter'' to "the perfect fluid"  

E-Print Network (OSTI)

Experimental Physics with Relativistic Heavy Ions dates from 1992 when a beam of 197Au of energy greater than 10A GeV/c first became available at the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) soon followed in 1994 by a 208Pb beam of 158A GeV/c at the Super Proton Synchrotron (SPS) at CERN (European Center for Nuclear Research). Previous pioneering measurements at the Berkeley Bevalac in the late 1970's and early 1980's were at much lower bombarding energies (~ 1 A GeV/c) where nuclear breakup rather than particle production is the dominant inelastic process in A+A collisions. More recently, starting in 2000, the Relativistic Heavy Ion Collider (RHIC) at BNL has produced head-on collisions of two 100A GeV beams of fully stripped Au ions, corresponding to nucleon-nucleon center-of-mass energy, sqrt(sNN)=200 GeV, total c.m. energy 200A GeV. The objective of this research program is to produce nuclear matter with extreme density and temperature, possibly resulting in a state of matter where the quarks and gluons normally confined inside individual nucleons (r laboratories: "A new state of matter", by CERN on Feb 10, 2000 and "The perfect fluid", by BNL on April 19, 2005.

M. J. Tannenbaum

2006-03-01T23:59:59.000Z

172

The Thermal Model at the Large Hadron Collider  

E-Print Network (OSTI)

A discussion is presented of results with identified particles at the Large Hadron Collider. Possible deviations from the standard statistical distributions are investigated by considering in detail results obtained using the Tsallis distribution. Matter-antimatter production is discussed within the framework of chemical equilibrium in \\pp and heavy ion collisions.

J. Cleymans

2012-03-26T23:59:59.000Z

173

The Heavy Ion Fusion Science Virtual National Laboratory Overview of Fusion Program  

E-Print Network (OSTI)

-pg white paper. Join us in a new IFE skunkworks. #12;11/30/2009 The Heavy Ion Fusion Science Virtual.1, from page 43 of the HIF White Paper prepared for the FESAC HEDLP panel. The proposed OFES heavy ion diagnostics (Bieniosek/Barnard talks), as well as adding more acceleration cells to extend accessible WDM

174

Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions  

E-Print Network (OSTI)

We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

2007-11-12T23:59:59.000Z

175

Beam instrumentation for the BNL Heavy Ion Transfer Line  

Science Conference Proceedings (OSTI)

The Heavy Ion Transfer Line (HITL) was constructed to transport beams from the BNL Tandem Van de Graaff (TVDG) to be injected into the AGS. Because the beam line is approximately 2000 feet long and the particle rigidity is so low, 20 beam monitor boxes were placed along the line. The intensity ranges from 1 to 100 nanoAmps for the dc trace beam used for line set-up, to over 100 ..mu..A for the pulsed beam to be injected into the AGS. Profiles are measured using multiwire arrays (HARPS) while Faraday cups and beam transformers monitor the intensity. The electronics stations are operated through 3 Instrumentation Controllers networked to Apollo workstations in the TVDG and AGS control rooms. Details of the detectors and electronics designs and performance will be given.

Witkover, R.L.; Buxton, W.; Castillo, V.; Feigenbaum, I.; Lazos, A.; Li, Z.G.; Smith, G.; Stoehr, R.

1987-01-01T23:59:59.000Z

176

Statistical Model of Heavy-Ion Fusion-Fission Reactions  

E-Print Network (OSTI)

Cross-section and neutron-emission data from heavy-ion fusion-fission reactions are consistent with the fission of fully equilibrated systems with fission lifetime estimates obtained via a Kramers-modified statistical model which takes into account the collective motion of the system about the ground state, the temperature dependence of the location and height of fission transition points, and the orientation degree of freedom. If the standard techniques for calculating fission lifetimes are used, then the calculated excitation-energy dependence of fission lifetimes is incorrect. We see no evidence to suggest that the nuclear viscosity has a temperature dependence. The strong increase in the nuclear viscosity above a temperature of approximately 1.3 MeV deduced by others is an artifact generated by an inadequate fission model.

J. P. Lestone; S. G. McCalla

2008-07-21T23:59:59.000Z

177

Medium effects on charged pion ratio in heavy ion collisions  

E-Print Network (OSTI)

We have recently studied in the delta-resonance--nucleon-hole model the dependence of the pion spectral function in hot dense asymmetric nuclear matter on the charge of the pion due to the pion p-wave interaction in nuclear medium. In a thermal model, this isospin-dependent effect enhances the ratio of negatively charged to positively charged pions in neutron-rich nuclear matter, and the effect is comparable to that due to the uncertainties in the theoretically predicted stiffness of nuclear symmetry energy at high densities. This effect is, however, reversed if we also take into account the s-wave interaction of the pion in nuclear medium as given by chiral perturbation theory, resulting instead in a slightly reduced ratio of negatively charged to positively charged pions. Relevance of our results to the determination of the nuclear symmetry energy from the ratio of negatively to positively charged pions produced in heavy ion collisions is discussed.

Che Ming Ko; Yongseok Oh; Jun Xu

2010-02-01T23:59:59.000Z

178

Nuclear deformation effect on the binding energies in heavy ions  

E-Print Network (OSTI)

Nuclear deformation effects on the binding energies in heavy ions are investigated. Approximate formulas for the nuclear-size correction and the isotope shift for deformed nuclei are derived. Combined with direct numerical evaluations, these formulas are employed to reanalyse experimental data on the nuclear-charge-distribution parameters in $^{238}\\textrm{U}$ and to revise the nuclear-size corrections to the binding energies in H- and Li-like $^{238}\\textrm{U}$. As a result, the theoretical uncertainties for the ground-state Lamb shift in $^{238}\\textrm{U}^{91+}$ and for the $2p_{1/2}-2s$ transition energy in $^{238}\\textrm{U}^{89+}$ are significantly reduced. The isotope shift of the $2p_{j}-2s$ transition energies for $^{142}\\textrm{Nd}^{57+}$ and $^{150}\\textrm{Nd}^{57+}$ is also evaluated including nuclear size and nuclear recoil effects within a full QED treatment.

Kozhedub, Y S; Shabaev, V M; Tupitsyn, I I; Brandau, C; Kozhuharov, C; Plunien, G; Sthlker, T

2007-01-01T23:59:59.000Z

179

Heavy ion collisions: Correlations and Fluctuations in particle production  

E-Print Network (OSTI)

Correlations and fluctuations (the latter are directly related to the 2-particle correlations) is one of the important directions in analysis of heavy ion collisions. At the current stage of RHIC exploration, when the details matter, basically any physics question is addressed with help of correlation techniques. In this talk I start with a general introduction to the correlation and fluctuation formalism and discuss weak and strong sides of different type of observables. In more detail, I discuss the two-particle $p_t$ correlations/$\\mpt$ fluctuations. In spite of not observing any dramatic changes in the event-by-event fluctuations with energy, which would indicate a possible phase transition, such correlations measurements remain an interesting and important subject, bringing valuable information. Lastly, I show how radial flow can generate characteristic azimuthal, transverse momentum and rapidity correlations, which could qualitatively explain many of recently observed phenomena in nuclear collisions.

Sergei A. Voloshin

2005-05-02T23:59:59.000Z

180

From chemical freezeout to critical conditions in heavy ion collisions  

E-Print Network (OSTI)

We compare the statistical thermodynamics of hadron resonance gas with recent LGT results at finite chemical potential. We argue that for $T\\leq T_c$ the equation of state derived from Monte--Carlo simulations of two quark--flavor QCD at finite chemical potential is consistent with that of a hadron resonance gas when applying the same set of approximations as used in LGT calculations. We indicate the relation of chemical freezeout conditions obtained from a detailed analysis of particle production in heavy ion collisions with the critical conditions required for deconfinement. We argue that the position of a hadron--quark gluon boundary line in temperature chemical potential plane can be determined in terms of the resonance gas model by the condition of fixed energy density.

Krzysztof Redlich

2004-06-23T23:59:59.000Z

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181

Multi Module Modeling of Ultra-Relativistic Heavy Ion Collisions.  

SciTech Connect

Multi Module Model is required for the realistic and detailed description of an ultrarelativistic heavy ion reaction. We are working in the framework of such a model: initial stages are described by Effective String Rope Model with expanding final streaks; hydrodynamical approach is used for the intermediate stages. This paper is mainly devoted to Third Module - the one dealing with Freeze Out (FO). Two possibilities are discussed in details: (A) freeze out at the constant time hypersurface, where the statistical production model is used to describe post FO particle species; and (B) simultaneous hadronization and freeze out from supercooled QGP. For the last case the ALCOR-like algorithm for calculation of the post FO particle species is presented, due to the fact that these do not have time to reach chemical equilibrium.

Magas, V. K.; Csernai, L. P. (Lszl P.); Keranen, A.; Manninen, J.; Strottman, D. D. (Daniel D.)

2002-01-01T23:59:59.000Z

182

Consequences of energy conservation in relativistic heavy-ion collisions  

E-Print Network (OSTI)

Complete characterization of particle production and emission in relativistic heavy-ion collisions is in general not feasible experimentally. This work demonstrates, however, that the availability of essentially complete pseudorapidity distributions for charged particles allows for a reliable estimate of the average transverse momenta and energy of emitted particles by requiring energy conservation in the process. The results of such an analysis for Au+Au collisions at sqrt{s_{NN}}= 130 and 200 GeV are compared with measurements of mean-p_T and mean-E_T in regions where such measurements are available. The mean-p_T dependence on pseudorapidity for Au+Au collisions at 130 and 200 GeV is given for different collision centralities.

B. B. Back

2005-08-15T23:59:59.000Z

183

Development of long-lived thick carbon stripper foils for high energy heavy ion accelerators by a heavy ion beam sputtering method  

Science Conference Proceedings (OSTI)

In the past decade, we have developed extremely long-lived carbon stripper foils of 1-50 {mu}g/cm{sup 2} thickness prepared by a heavy ion beam sputtering method. These foils were mainly used for low energy heavy ion beams. Recently, high energy negative Hydrogen and heavy ion accelerators have started to use carbon stripper foils of over 100 {mu}g/cm{sup 2} in thickness. However, the heavy ion beam sputtering method was unsuccessful in production of foils thicker than about 50 {mu}g/cm{sup 2} because of the collapse of carbon particle build-up from substrates during the sputtering process. The reproduction probability of the foils was less than 25%, and most of them had surface defects. However, these defects were successfully eliminated by introducing higher beam energies of sputtering ions and a substrate heater during the sputtering process. In this report we describe a highly reproducible method for making thick carbon stripper foils by a heavy ion beam sputtering with a Krypton ion beam.

Muto, Hideshi [Center of General Education, Tokyo University of Science, Suwa, 5000-1 Toyohira, Chino Nagano 391-0292 (Japan); Ohshiro, Yukimitsu [Center for Nuclear Study, School of Science, University of Tokyo, 2-1 Hirosawa, Riken Campus, Wako Saitama 351-0198 (Japan); Kawasaki, Katsunori [Van de Graaff Laboratory, Department of Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro Tokyo 152-8551 (Japan); Oyaizu, Michihiro [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan); Hattori, Toshiyuki [Heavy Ion Cancer Therapy Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage Chiba 263-855 (Japan)

2013-04-19T23:59:59.000Z

184

Effect of the Wood-Saxon nuclear distribution on the chiral magnetic field in Relativistic Heavy-ion Collisions  

E-Print Network (OSTI)

The formation of the QCD vacuum with nonzero winding number $Q_w$ during relativistic heavy-ion collisions breaks the parity and charge-parity symmetry. A new kind of field configuration can separate charge in the presence of a background magnetic field-the "chiral magnetic effect". The strong magnetic field and the QCD vacuum can both completely be produced in the noncentral nuclear-nuclear collision. Basing on the theory of Kharzeev,Mclerran and Warringa, we use the Wood-Saxon nucleon distribution to replace that of the uniform distribution to improve the magnetic field calculation method of the noncentral collision. The chiral magnetic field distribution at LHC(Large Hadron Collider) energy regions are predicted. We also consider the contributions to the magnetic field of the total charge given by the produced quarks.

Yu-Jun Mo; Sheng-Qin Feng; Ya-Fei Shi

2013-08-20T23:59:59.000Z

185

The LHC as a Proton-Nucleus Collider  

E-Print Network (OSTI)

Following its initial operation as a proton-proton (p-p) and heavy-ion (208Pb82+-208Pb82+) collider, the LHC is expected to operate as a p-Pb collider. Later it may collide protons with other lighter nuclei such as 40Ar18+ or 16O8+. We show how the existing proton and lead-ion injector chains may be efficiently operated in tandem to provide these hybrid collisions. The two-in-one magnet design of the LHC main rings imposes different revolution frequencies for the two beams in part of the magnetic cycle. We discuss and evaluate the consequences for beam dynamics and estimate the potential performance of the LHC as a proton-nucleus collider.

Carli, C

2006-01-01T23:59:59.000Z

186

A Scaled Final Focus Experiment for Heavy Ion Fusion  

SciTech Connect

A one-tenth dimensionally scaled version of a final focus sub-system design for a heavy ion fusion driver is built and tested. By properly scaling the physics parameters that relate particle energy and mass, beam current, beam emittance, and focusing field, the transverse dynamics of a driver scale final focus are replicated in a small laboratory beam. The experiment uses a 95 {micro}A beam of 160 keV Cs{sup +} ions to study the dynamics as the beam is brought to a ballistic focus in a lattice of six quadrupole magnets. Diagnostic stations along the experiment track the evolution of the transverse phase space of the beam. The measured focal spot size is consistent with calculations and the report of the design on which the experiment is based. By uniformly varying the strengths of the focusing fields in the lattice, the chromatic effect of a small energy deviation on the spot size can be reproduced. This is done for {+-}1% and {+-}2% shifts and the changes in the focus are measured. Additionally, a 400 {micro}A beam is propagated through the experiment and partially neutralized after the last magnet using electrons released from a hot tungsten filament. The increase in beam current allows for the observation of significant effects on both the size and shape of the focal spot when the electrons are added.

MacLaren, Stephan, Alexander

2000-09-19T23:59:59.000Z

187

Workshop on Accelerators for Heavy Ion Fusion: Summary Report of the Workshop  

SciTech Connect

The Workshop on Accelerators for Heavy Ion Fusion was held at Lawrence Berkeley National Laboratory May 23-26, 2011. The workshop began with plenary sessions to review the state of the art in HIF (heavy ion fusion), followed by parallel working groups, and concluded with a plenary session to review the results. There were five working groups: IFE (inertial fusion energy) targets, RF approach to HIF, induction accelerator approach to HIF, chamber and driver interface, ion sources and injectors.

Seidl, P.A.; Barnard, J.J.

2011-04-29T23:59:59.000Z

188

Atomic nuclei decay modes by spontaneous emission of heavy ions  

Science Conference Proceedings (OSTI)

The great majority of the known nuclides with Z>40, including the so-called stable nuclides, are metastable with respect to several modes of spontaneous superasymmetric splitting. A model extended from the fission theory of alpha decay allows one to estimate the lifetimes and the branching ratios relative to the alpha decay for these natural radioactivities. From a huge amount of systematic calculations it is concluded that the process should proceed with maximum intensity in the trans-lead nuclei, where the minimum lifetime is obtained from parent-emitted heavy ion combinations leading to a magic (/sup 208/Pb) or almost magic daughter nucleus. More than 140 nuclides with atomic number smaller than 25 are possible candidates to be emitted from heavy nuclei, with half-lives in the range of 10/sup 10/--10/sup 30/ s: /sup 5/He, /sup 8en-dash10/Be, /sup 11,12/B, /sup 12en-dash16/C, /sup 13en-dash17/N, /sup 15en-dash22/O, /sup 18en-dash23/F, /sup 20en-dash26/Ne, /sup 23en-dash28/Na, /sup 23en-dash30/Mg, /sup 27en-dash32/Al, /sup 28en-dash36/Si, /sup 31en-dash39/P, /sup 32en-dash42/S, /sup 35en-dash45/Cl, /sup 37en-dash47/Ar, /sup 40en-dash49/ K, . .Ca, /sup 44en-dash53/ Sc, /sup 46en-dash53/Ti, /sup 48en-dash54/V, and /sup 49en-dash55/ Cr. The shell structure and the pairing effects are clearly manifested in these new decay modes.

Poenaru, D.N.; Ivascu, M.; Sndulescu, A.; Greiner, W.

1985-08-01T23:59:59.000Z

189

Magnetic effects in heavy-ion collisions at intermediate energies  

E-Print Network (OSTI)

The time-evolution and space-distribution of internal electromagnetic fields in heavy-ion reactions at beam energies between 200 and 2000 MeV/nucleon are studied within an Isospin-dependent Boltzmann-Uhling-Uhlenbeck transport model IBUU11. While the magnetic field can reach about $7\\times 10^{16}$ G which is significantly higher than the estimated surface magnetic field ($\\sim 10^{15}$ G) of magnetars, it has almost no effect on nucleon observables as the Lorentz force is normally much weaker than the nuclear force. Very interestingly, however, the magnetic field generated by the projectile-like (target-like) spectator has a strong focusing/diverging effect on positive/negative pions at forward (backward) rapidities. Consequently, the differential $\\pi^-/\\pi^+$ ratio as a function of rapidity is significantly altered by the magnetic field while the total multiplicities of both positive and negative pions remain about the same. At beam energies above about 1 GeV/nucleon, while the integrated ratio of total $\\pi^-$ to $\\pi^+$ multiplicities is not, the differential $\\pi^-/\\pi^+$ ratio is sensitive to the density dependence of nuclear symmetry energy $E_{\\rm{sym}}(\\rho)$. Our findings suggest that magnetic effects should be carefully considered in future studies of using the differential $\\pi^-/\\pi^+$ ratio as a probe of the $E_{\\rm{sym}}(\\rho)$ at supra-saturation densities.

Li Ou; Bao-An Li

2011-07-16T23:59:59.000Z

190

Hydro-kinetic approach to relativistic heavy ion collisions  

E-Print Network (OSTI)

We develop a combined hydro-kinetic approach which incorporates a hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for the Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to a sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support an earlier decoupling of higher $p_{T}$ particles. By performing numerical simulations for various initial conditions and equations of state we identify several characteristic features of the bulk QCD matter evolution preferred in view of the current analysis of heavy ion collisions at RHIC energies.

S. V. Akkelin; Y. Hama; Iu. A. Karpenko; Yu. M. Sinyukov

2008-04-25T23:59:59.000Z

191

Heavy Ion Beams for Investigation of Thermophysical Properties  

E-Print Network (OSTI)

Perspectives for study of thermophysical properties via uniform quasi-stationary volumetric heating under Heavy Ion Beam (HIB) heating with moderate but realistic energy deposition (~ 1 kJ/g) are under discussion. New quasi-isobaric regime of heating is proposed as combination of the HIB energy deposition with the use of highly dispersed porous material as an irradiating sample. Regime of "tracing saturation curve" is proposed also when heating the evaporating porous materials. Consequent preferences and priorities are emphasized. In frames of this technique HIB could became an uncompetitive tool for study of phase transition phenomenon for a wide number of materials with high-temperature location of critical point. Two important thermophysical problems, which could approve using of HIB facility, are discussed as the first-row candidates. Evaporation in Uranium is one of the most tempting candidates to be studied under HIB heating in such manner. When being successful this experiment has a good chance to resolve the old contradiction within the problem of Uranium critical point parameters estimations. The heating by HIB seems to be especially promising as an effective tool for systematic study of so-called "non-congruent" phase transition -- striking and mostly unusual sort of high-temperature phase equilibrium in chemically active strongly coupled plasmas. Phase transition in uranium dioxide is remarkable example of such non-congruency. New information on the thermophysical properties of phase transitions in uranium and uranium dioxide could be valuable for application in nuclear reactor safety analysis

Igor Iosilevskiy

2010-05-23T23:59:59.000Z

192

Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields  

DOE Green Energy (OSTI)

Some years ago it was suggested that halogen negative ions [1]could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons -- can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion-ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

Grisham, L.R.; Kwan, J.W.

2008-08-01T23:59:59.000Z

193

Molecular dynamics simulations of swift heavy ion induced defect recovery in SiC  

SciTech Connect

Swift heavy ions induce a high density of electronic excitations that can cause the formation of amorphous ion tracks in insulators. No ion tracks have been observed in the semiconductor SiC, but recent experimental work suggests that irradiation damaged SiC can undergo defect recovery under swift heavy ion irradiation. It is believed that local heating of the lattice due to the electronic energy deposition can anneal, and thereby recover, some of the disordered structure. We simulate the local heating due to the ions by the inelastic thermal spike model and perform molecular dynamics simulations of dierent model damage states to study the defect recovery on an atomistic level. We find significant recovery of point defects and a disordered layer, as well as recrystallization at the amorphous-to-crystalline interface of an amorphous layer. The simulation results support the swift heavy ion annealing hypothesis.Swift heavy ions induce a high density of electronic excitations that can cause the formation of amorphous ion tracks in insulators. No ion tracks have been observed in the semiconductor SiC, but recent experimental work suggests that irradiation damaged SiC can undergo defect recovery under swift heavy ion irradiation. It is believed that local heating of the lattice due to the electronic energy deposition can anneal, and thereby recover, some of the disordered structure. We simulate the local heating due to the ions by the inelastic thermal spike model and perform molecular dynamics simulations of dierent model damage states to study the defect recovery on an atomistic level. We find significant recovery of point defects and a disordered layer, as well as recrystallization at the amorphous-to-crystalline interface of an amorphous layer. The simulation results support the swift heavy ion annealing hypothesis.

Backman, Marie [University of Tennessee, Knoxville (UTK); Toulemonde, Marcel [CEA-CNRS-ENSICAEN-University of Caen, FRANCE; Pakarinen, Olli H [University of Helsinki; Juslin, Niklas [University of Tennessee, Knoxville (UTK); Djurabekova, Flyura [University of Helsinki; Nordlund, Kai [University of Helsinki; Debelle, Aurelien [Universite Paris Sud, Orsay, France; Weber, William J [ORNL

2013-01-01T23:59:59.000Z

194

DOE - Office of Legacy Management -- Yale Heavy Ion Linear Accelerator - CT  

NLE Websites -- All DOE Office Websites (Extended Search)

Yale Heavy Ion Linear Accelerator - Yale Heavy Ion Linear Accelerator - CT 05 FUSRAP Considered Sites Site: Yale Heavy Ion Linear Accelerator (CT.05) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: New Haven , Connecticut CT.05-1 Evaluation Year: 1987 CT.05-3 Site Operations: Research and development with solvents. CT.05-1 Site Disposition: Eliminated - Potential for contamination remote based on limited amount of materials handled CT.05-3 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Uranium, Radium CT.05-1 Radiological Survey(s): No Site Status: Eliminated from consideration under FUSRAP Also see Documents Related to Yale Heavy Ion Linear Accelerator CT.05-1 - MED Memorandum; To the Files, Thru Ruhoff, et. al.;

195

HEAVY ION FUSION HALF-YEAR REPORT APRIL 1, 1980 - SEPTEMBER 30, 1980  

E-Print Network (OSTI)

of Rochester Ravi N. Sudan KMS Fusion, Inc. Henry J. GombergOF CALIFORNIA Accelerator & Fusion Research DivisionHEAVY ION FUSION HALF-YEAR REPORT APRIL 1, 1980 - SEPTEMBER

Authors, Various

2010-01-01T23:59:59.000Z

196

Generation, transport and focusing of high-brightness heavy ion beams  

E-Print Network (OSTI)

The Neutralized Transport Experiment (NTX) has been built at the Heavy Ion Fusion Virtual National Laboratory. NTX is the first successful integrated beam system experiment that explores various physical phenomena, and ...

Henestroza, Enrique

2006-01-01T23:59:59.000Z

197

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency  

E-Print Network (OSTI)

M J of fusion yield. This NIF capsule design ab- sorbs 200capsules the size of the NIF capsule with heavy-ion beams (designs emerge, and, if the NIF's ignition campaign is also

Logan, B.G.

2008-01-01T23:59:59.000Z

198

Direct Drive Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency  

E-Print Network (OSTI)

of fusion yield [16]. This NIF capsule design absorbs 200 kJcapsules the size of the NIF capsule with heavy ion beams (designs emerge, and, i f the NIF's ignition campaign is also

Logan, B. Grant

2008-01-01T23:59:59.000Z

199

Heavy-ion Collisions: Direct and indirect probes of the density and temperature dependence of Esym  

E-Print Network (OSTI)

Heavy-ion collisions provide a versatile terrestrial probe of the nuclear equation of state through the formation of nuclear matter at a wide variety of temperatures, densities, and pressures. Direct and indirect approaches for constraining the density dependence of the symmetry energy using heavy-ion collisions have been developed. The direct approach relies on scaling methods which attempt to connect isotopic fragment distributions to the symmetry energy. Using the indirect approach constraints on the equation of state are extracted from comparison of experimental results and theoretical transport calculations which utilize effective nucleon-nucleon interactions. Besides exploring the density dependence of the equation of state, heavy-ion collisions are simultaneously probing different temperature gradients of nuclear matter allowing for the temperature dependence of the symmetry energy to be examined. The current progress and open questions related to constraining the density and temperature dependence of the symmetry energy with heavy-ion collisions are discussed in the review.

Z. Kohley; S. J. Yennello

2014-01-22T23:59:59.000Z

200

Turbulent Transport and Heating of Trace Heavy Ions in Hot Magnetized Plasmas  

E-Print Network (OSTI)

Scaling laws for the transport and heating of trace heavy ions in low-frequency magnetized plasma turbulence are derived and compared with direct numerical simulations. The predicted dependences of turbulent fluxes and ...

Barnes, Michael

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Heavy-ion-induced digital single event transients in a 180 nm fully depleted SOI process  

E-Print Network (OSTI)

Heavy-ion-induced single events transients (SETs) in advanced digital circuits are a significant reliability issue for space-based systems. SET pulse widths in silicon-on-insulator (SOI) technologies are often significantly ...

Gouker, Pascale M.

202

Scientific issues in future induction linac accelerators for heavy ion fusion  

E-Print Network (OSTI)

Miller, M. Tabak, Nuc. Fusion, 39, 883 (1999). [2] S.S. Yu,W.M. Sharp, D.R. Welch, Fusion Science and Technology, 44,Transport for Heavy Ion Fusion", in these proceedings. [18

Celata, C.M.

2004-01-01T23:59:59.000Z

203

Measurements of phi meson production in relativistic heavy-ion collisions at RHIC  

Science Conference Proceedings (OSTI)

We present results for the measurement of {phi} meson production via its charged kaon decay channel {phi} {yields} K{sup +}K{sup -} in Au + Au collisions at {radical}s{sub NN} = 62.4, 130, and 200 GeV, and in p + p and d + Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (|y| energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for {phi} production at RHIC. The {Omega}/{phi} yield ratio as a function of p{sub T} is consistent with a model based on the recombination of thermal s quarks up to p{sub T} {approx} 4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, R{sub dAu}, for the {phi} meson increases above unity at intermediate p{sub T}, similar to that for pions and protons, while R{sub AA} is suppressed due to the energy loss effect in central Au + Au collisions. Number of constituent quark scaling of both R{sub cp} and v{sub 2} for the {phi} meson with respect to other hadrons in Au + Au collisions at {radical}s{sub NN} = 200 GeV at intermediate p{sub T} is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate p{sub T} region at RHIC.

STAR Coll

2009-06-16T23:59:59.000Z

204

Effect of jets on $v_4/v_2^2$ ratio and constituent quark scaling in relativistic heavy-ion collisions  

E-Print Network (OSTI)

The Monte Carlo HYDJET++ model, that combines parametrized hydrodynamics with jets, is employed to study formation of second v_2 and fourth v_4 components of the anisotropic flow in ultrarelativistic heavy-ion collisions at energies of the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), sqrt{s}=200 AGeV and sqrt{s}=2.76 ATeV, respectively. It is shown that the quenched jets contribute to the soft part of the v_2(p_T) and v_4(p_T) spectra. The jets increase the ratio v_4/v_2^2 thus leading to deviations of the ratio from the value of 0.5 predicted by the ideal hydrodynamics. Together with the event-by-event fluctuations, the influence of jets can explain quantitatively the ratio v_4/v_2^2 at p_T energies and qualitatively the rise of its high-p_T tail at LHC. Jets are also responsible for violation of the number-of-constituent-quark (NCQ) scaling at LHC despite the fact that the scaling is fulfilled for the hydro-part of particle spectra.

L. Bravina; B. H. Brusheim Johansson; G. Eyyubova; E. Zabrodin

2013-02-26T23:59:59.000Z

205

Effect of jets on $v_4/v_2^2$ ratio and constituent quark scaling in relativistic heavy-ion collisions  

E-Print Network (OSTI)

The Monte Carlo HYDJET++ model, that combines parametrized hydrodynamics with jets, is employed to study formation of second v_2 and fourth v_4 components of the anisotropic flow in ultrarelativistic heavy-ion collisions at energies of the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), sqrt{s}=200 AGeV and sqrt{s}=2.76 ATeV, respectively. It is shown that the quenched jets contribute to the soft part of the v_2(p_T) and v_4(p_T) spectra. The jets increase the ratio v_4/v_2^2 thus leading to deviations of the ratio from the value of 0.5 predicted by the ideal hydrodynamics. Together with the event-by-event fluctuations, the influence of jets can explain quantitatively the ratio v_4/v_2^2 at p_T energies and qualitatively the rise of its high-p_T tail at LHC. Jets are also responsible for violation of the number-of-constituent-quark (NCQ) scaling at LHC despite the fact that the scaling is fulfilled for the hydro-part of particle spectra.

Bravina, L; Eyyubova, G; Zabrodin, E

2013-01-01T23:59:59.000Z

206

Level-3 Trigger for a Heavy Ion Experiment at LHC  

Science Conference Proceedings (OSTI)

At the upcoming Large Hadron Collider (LHC) at CERN one expects to measure 20,000 particles in a single Pb-Pb event resulting in a data rate of ?75MByte/event. The event rate is limited by the bandwidth of the storage system. Higher rates are possible ...

U. Frankenfeld; H. Helstrup; J. Lien; Volker Lindenstruth; Dieter Rhrich; M. Schulz; B. Skaali; Timm M. Steinbeck; K. Ullaland; Anders Strand Vestb; Arne Wiebalck

2001-08-01T23:59:59.000Z

207

Recent Heavy Flavor Results at RHIC  

E-Print Network (OSTI)

We summarize the recent experimental results of heavy favor physics from the Relativistic Heavy Ion Collider (RHIC) in Brookhaven National Lab (BNL) at Long Island, New York, USA.We will discuss the directly reconstructed open charm mesons as well as electrons from heavy favor hadron decays. The charm and bottom quark production cross-sections have also been measured. We will also discuss JPsi and Upsilon states in p+p and heavy ion collisions. The studies described here were carried out and reported by the STAR and PHENIX collaborations at RHIC.

Wenqin Xu

2011-10-13T23:59:59.000Z

208

Studies of complex fragment emission in heavy ion reactions  

Science Conference Proceedings (OSTI)

Our work involves the study of intermediate energy heavy-ion nuclear reactions. This work has two foci. On the one hand, we desire to learn about the properties of nuclear matter under abnormal conditions, in this energy domain, predominately low densities. This purpose runs abreast of the second, which is the study of the relevant reaction mechanisms. The two objectives are inexorably linked because our experimental laboratory for studying nuclear matter properties is a dynamic one. We are forced to ask how nuclear matter properties, such as phase transitions, are reflected in the dynamics of the reactions. It may be that irrefutable information about nuclear matter will not be extracted from the reaction work. Nevertheless, we are compelled to undertake this effort not only because it is the only game in town and as yet we do not know that information cannot be extracted, but also because of our second objective. The process leads to an understanding of the reaction mechanism themselves and therefore to the response characteristics of finite, perhaps non-equilibrium, strongly interacting systems. Our program has been: To study energy, mass, and angular momentum deposition by studying incomplete fusion reactions. To gain confidence that we understand how highly excited systems decompose by studying all emissions from the highly excited systems. To push these kinds of studies into the intermediate energy domain, with excitation function studies. And attempt to learn about the dynamics of the decays using particle-particle correlations. In the last effort, we have decided to focus on simple systems, where we believe, definitive statements are possible. These avenues of research share a common theme, large complex fragment production.

Charity, R.J.; Sobotka, L.G.

1992-01-01T23:59:59.000Z

209

Heavy quark production from jet conversions in a quark-gluon plasma  

E-Print Network (OSTI)

Recently, it has been demonstrated that the chemical composition of jets in heavy ion collisions is significantly altered compared to the jets in the vacuum. This signal can be used to probe the medium formed in nuclear collisions. In this study we investigate the possibility that fast light quarks and gluons can convert to heavy quarks when passing through a quark-gluon plasma. We study the rate of light to heavy jet conversions in a consistent Fokker-Planck framework and investigate their impact on the production of high-p(T) charm and bottom quarks at the Relativistic Heavy Ion Collider and the Large Hadron Collider.

Liu, W.; Fries, Rainer J.

2008-01-01T23:59:59.000Z

210

Probing the Nuclear Symmetry Energy with Heavy-Ion Reactions Induced by Neutron-Rich Nuclei  

E-Print Network (OSTI)

Heavy-ion reactions induced by neutron-rich nuclei provide a unique means to investigate the equation of state of isospin-asymmetric nuclear matter, especially the density dependence of the nuclear symmetry energy. In particular, recent analyses of the isospin diffusion data in heavy-ion reactions have already put a stringent constraint on the nuclear symmetry energy around the nuclear matter saturation density. We review this exciting result and discuss its implications on nuclear effective interactions and the neutron skin thickness of heavy nuclei. In addition, we also review the theoretical progress on probing the high density behaviors of the nuclear symmetry energy in heavy-ion reactions induced by high energy radioactive beams.

Chen, Lie-Wen; Li, Bao-An; Yong, Gao-Chan

2007-01-01T23:59:59.000Z

211

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency  

SciTech Connect

Issues with coupling efficiency, beam illumination symmetry, and Rayleigh-Taylor instability are discussed for spherical heavy-ion-beam-driven targets with and without hohlraums. Efficient coupling of heavy-ion beams to compress direct-drive inertial fusion targets without hohlraums is found to require ion range increasing several-fold during the drive pulse. One-dimensional implosion calculations using the LASNEX inertial confinement fusion target physics code shows the ion range increasing fourfold during the drive pulse to keep ion energy deposition following closely behind the imploding ablation front, resulting in high coupling efficiencies (shell kinetic energy/incident beam energy of 16% to 18%). Ways to increase beam ion range while mitigating Rayleigh-Taylor instabilities are discussed for future work.

Logan, B.G.; Perkins, L.J.; Barnard, J.J.

2008-05-16T23:59:59.000Z

212

Modeling of Heavy Metals Ions Adsorption by Polyamidoamine ...  

Science Conference Proceedings (OSTI)

... that employ PAMAM dendrimers for adsorption of heavy metals from wastewater. ... Heat Treatment of Black Dross for the Production of a Value Added Material ... Mullites Bodies Produced From the Kaolin Residue Using Microwave Energy.

213

BEAM-BASED NON-LINEAR OPTICS CORRECTIONS IN COLLIDERS.  

Science Conference Proceedings (OSTI)

A method has been developed to measure and correct operationally the non-linear effects of the final focusing magnets in colliders, that gives access to the effects of multi-pole errors by applying closed orbit bumps, and analyzing the resulting tune and orbit shifts. This technique has been tested and used during 4 years of RHIC (the Relativistic Heavy Ion Collider at BNL) operations. I will discuss here the theoretical basis of the method, the experimental set-up, the correction results, the present understanding of the machine model, the potential and limitations of the method itself as compared with other non-linear correction techniques.

PILAT, R.; LUO, Y.; MALITSKY, N.; PTITSYN, V.

2005-05-16T23:59:59.000Z

214

e-RHIC: Future electron-ion collider at BNL (405th Brookhaven Lecture)  

SciTech Connect

While RHIC scientists continue their quest to look deep into nuclear phenomena resulting from collisions of ion beams and beams of polarized protons, new design work is under way for a possible extension of RHIC to include e-RHIC, a 10-billion electron volt, high-intensity polarized proton beam.

Ptitsyn, Vadim (Ph.D., Collider-Accelerator Department)

2005-06-22T23:59:59.000Z

215

Swift heavy ion irradiation of Pt nanocrystals: I. shape transformation and dissolution  

Science Conference Proceedings (OSTI)

We report on the effects of swift heavy ion irradiation of embedded Pt nanocrystals (NCs), which change from spheres to prolate spheroids to rods upon irradiation. Using a broad range of ion irradiation energies and NC mean sizes we demonstrate that the elongation and dissolution processes are energy and size dependent, attaining comparable levels of shape transformation and dissolution upon a given energy density deposited in the matrix. The NC shape transformation remains operative despite discontinuous ion tracks in the matrix and exhibits a constant threshold size for elongation. In contrast, for ion irradiations in which the ion tracks are continuous, the threshold size for elongation is clearly energy dependent.

Giulian, R.; Araujo, L.L.; Kluth, P.; Sprouster, D.J.; Schnohr, C.S.; Byrne, A.P.; Ridgway, M.C. (ANU)

2011-12-09T23:59:59.000Z

216

Calculation Of Change-Changing Cross Sections Of IONS Or Atoms Colliding With Fast IONS Using The Classical Trajectory Method  

DOE Green Energy (OSTI)

Evaluation of ion-atom charge-changing cross sections is needed for many accelerator applications. A classical trajectory Monte Carlo (CTMC) simulation has been used to calculate ionization and charge exchange cross sections. For benchmarking purposes, an extensive study has been performed for the simple case of hydrogen and helium targets in collisions with various ions. Despite the fact that the simulation only accounts for classical mechanics, the calculations are comparable to experimental results for projectile velocities in the region corresponding to the vicinity of the maximum cross section. Shortcomings of the CTMC method for multielectron target atoms are discussed.

Kaganovich, I. D., Shnidman, Ariel, Mebane, Harrison, Davidson, R.C.

2008-10-10T23:59:59.000Z

217

HIGH-ENERGY HEAVY-ION BEAMS AS IGNITERS FOR COMMERCIAL-SCALE INTERTIAL-FUSION POWER PLANTS  

E-Print Network (OSTI)

Nucl. Proceedings of the Brookhaven Workshop on Heavy IonOctober 17-21, 1977- Brookhaven National Laboratory Report (the physics of Argonne, Brookhaven, Lawrence Berkeley, and

Judd, D.L.

2011-01-01T23:59:59.000Z

218

Proton and heavy ion upsets in GaAs MESFET devices  

Science Conference Proceedings (OSTI)

This paper reports on proton and heavy SEU data that has been obtained for devices made by several GaAs MESFET manufacturers. Proton energy dependence and proton and heavy ion upset cross sections are reported. Measurements of charge collection from latches designed with various gate widths show that charge collection depths appear deeper than the 1 {mu}m depth expected. Critical charge does not scale linearly with area. Proton upset cross sections are reduced with increased device width.

Weatherford, T.R.; Tran, L. (Sachs/Freeman Associates, Inc., Bowie, MD (United States)); Stapor, W.J.; Petersen, E.L.; Langworthy, J.B.; McMorrow, D. (Naval Research Lab., Washington, DC (United States)); Abdel-Kader, W.G.; McNulty, P.J. (Clemson Univ., SC (United States). Dept. of Physics and Astronomy)

1991-12-01T23:59:59.000Z

219

Cost reduction possibilities for a heavy-ion accelerator for inertial confinement fusion  

SciTech Connect

A design was produced for a single module in a cost-optimized accelerator appropriate for a commercial heavy-ion power plant. The goal of the study was to determine if the cost of the accelerator module could be reduced through design options, selection of materials, and manufacturing techniques. Independent cost estimates were obtained for the three main components of the module, and cost reductions of 20% from the cost calculated by the heavy-ion accelerator design/cost-minimization computer code LIACEP were identified. 3 refs., 23 figs.

Thayer, G.R.; Sims, J.R.; Henke, M.D.; Harris, D.B.; Dudziak, D.J.; Phillips, N.R.

1987-10-01T23:59:59.000Z

220

Lattice QCD and Hydro/Cascade Model of Heavy Ion Collisions  

E-Print Network (OSTI)

We report here on a recent lattice study of the QCD transition region at finite temperature and zero chemical potential using domain wall fermions (DWF). We also present a parameterization of the QCD equation of state obtained from lattice QCD that is suitable for use in hydrodynamics studies of heavy ion collisions. Finally, we show preliminary results from a multi-stage hydrodynamics/hadron cascade model of a heavy ion collision, in an attempt to understand how well the experimental data (e.g. particle spectra, elliptic flow, and HBT radii) can constrain the inputs (e.g. initial temperature, freezeout temperature, shear viscosity, equation of state) of the theoretical model.

Michael Cheng

2010-05-11T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Doorway state expansion approach to coupled channels problems and application to heavy ions  

SciTech Connect

The doorway expansion method is extended to coupled channels problems in low energy heavy ion collisions. As a test, it is applied to an exactly soluble model and the convergence problem is discussed. The method is then applied to heavy ion elastic scattering due to the optical potential and to a simple coupled channels problem. In both cases very good convergence is reached with six doorway states. The calculation with a single doorway is shown to be much better than the DWBA. 9 refs., 8 figs., 1 tab.

Breitschaft, A.M.S.; Canto, L.F.; Schechter, H. (Universidade Federal do Rio de Janeiro (Brazil)); Hussein, M.S. (Universidade de Sao Paulo (Brazil)); Moniz, E.J. (Massachusetts Institute of Technology, Cambridge, MA (United States))

1994-08-15T23:59:59.000Z

222

Photon decay in strong magnetic field in heavy-ion collisions  

E-Print Network (OSTI)

We calculate the photon pair production rate in strong magnetic field created in off-central heavy-ion collisions. Photon decay leads to depletion of the photon yield by a few percent at RHIC and by as much as 20% at the LHC. It also generates a substantial azimuthal asymmetry ("elliptic flow") of the final photon distribution. We estimate v_2~2% at RHIC and v_2~14% at LHC. Photon decay measurements is an important tool for studying the magnetic fields in early stages of heavy-ion collisions.

Tuchin, Kirill

2010-01-01T23:59:59.000Z

223

Lattice QCD and Hydro/Cascade Model of Heavy Ion Collisions  

E-Print Network (OSTI)

We report here on a recent lattice study of the QCD transition region at finite temperature and zero chemical potential using domain wall fermions (DWF). We also present a parameterization of the QCD equation of state obtained from lattice QCD that is suitable for use in hydrodynamics studies of heavy ion collisions. Finally, we show preliminary results from a multi-stage hydrodynamics/hadron cascade model of a heavy ion collision, in an attempt to understand how well the experimental data (e.g. particle spectra, elliptic flow, and HBT radii) can constrain the inputs (e.g. initial temperature, freezeout temperature, shear viscosity, equation of state) of the theoretical model.

Cheng, Michael

2010-01-01T23:59:59.000Z

224

Muon Muon Collider: Feasibility Study  

SciTech Connect

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of

Gallardo, J.C.; Palmer, R.B.; /Brookhaven; Tollestrup, A.V.; /Fermilab; Sessler, A.M.; /LBL, Berkeley; Skrinsky, A.N.; /Novosibirsk, IYF; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley

2012-04-05T23:59:59.000Z

225

More than mass proportional heating of heavy ions by supercritical collisionless shocks in the solar corona  

E-Print Network (OSTI)

We propose a new model for explaining the observations of more than mass proportional heating of heavy ions in the polar solar corona. We point out that a large number of small scale intermittent shock waves can be present in the solar corona. The energization mechanism is, essentially, the ion reflection off supercritical quasi-perpendicular collisionless shocks in the corona and the subsequent acceleration by the motional electric field ${\\bf E} = - (1/c) {\\bf V} \\times {\\bf B}$. The acceleration due to ${\\bf E}$ is perpendicular to the magnetic field, in agreement with observations, and is more than mass proportional with respect to protons, because the heavy ion orbit is mostly upstream of the quasi-perpendicular shock foot. The observed temperature ratios between O$^{5+}$ ions and protons in the polar corona, and between $\\alpha$ particles and protons in the solar wind are easily recovered.

Zimbardo, Gaetano

2009-01-01T23:59:59.000Z

226

Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a,  

E-Print Network (OSTI)

Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a, , F Available online 21 December 2010 Keywords: Solar wind sputtering Lunar regolith KREEP soil Potential a c t Lunar surface materials are exposed to $1 keV/amu solar-wind protons and heavy ions on almost

227

Targets for high-resolution studies with heavy-ion reactions  

SciTech Connect

Target problems in heavy ion reaction studies are discussed, including non-uniformity in thickness effects and the inability to fully compensate for reaction-site effects, both problems becoming more serious the heavier the ion. For the non-uniformity effects, the flatness of the target is very critical. Other problems not yet solved are beam-spot heating and the buildup of carbon. (PMA)

Erskine, J.R.

1975-01-01T23:59:59.000Z

228

Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring  

SciTech Connect

Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

Tr?bert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

2008-10-09T23:59:59.000Z

229

Search for Heavy Resonances Decaying to Taus in 7 TeV Proton-Proton Collisions at the Large Hadron Collider  

E-Print Network (OSTI)

Over the last few decades, the Standard Model (SM) of particle physics has been used as a means of understanding the world around us. However, there is an increasing amount of data that suggests the SM of particle physics only describes nature up to energies of the electroweak scale. Extensions to the SM have been developed as a means of explaining experimental observation. If these extensions are indeed the correct mathematical descriptions of nature, the Large Hadron Collider (LHC), located at the European Center for Nuclear Research (CERN) near Geneva, Switzerland, is expected to produce new and exciting physics signatures that can shed light on the evolution of our universe since the early hypothesized Big Bang. Of particular interest are models that may lead to events with highly energetic tau lepton pairs. In this dissertation, focus is placed on a possible search for new heavy gauge bosons decaying to highly energetic tau pairs using a data sample corresponding to an integrated luminosity of 36 pb^-1 of proton-proton collisions at sqrt(s) = 7 TeV collected with the CMS detector at the CERN LHC. The number of observed events in the data is in good agreement with the predictions for SM background processes. In the context of the Sequential SM, a Z0 with mass less than 468 GeV/c^2 is excluded at 95 percent credibility level, exceeding the sensitivity by the Tevatron experiments at the Fermi National Accelerator Laboratory.

Gurrola, Alfredo

2011-08-01T23:59:59.000Z

230

P{bar P} collider physics  

Science Conference Proceedings (OSTI)

A brief introduction to {bar p}p collider physics is given. Selected results from the collider experiments at the CERN S{bar p}pS and the Tevatron collider are described. The emphasis is on experimental aspects of {bar p}p collisions. Minimum bias physics and the production of jets, Intermediate Vector Bosons and heavy flavors is reviewed. The outlook for physics at hadron colliders for the near future is briefly discussed.

Demarteau, M. [State Univ. of New York, Stony Brook, NY (United States)

1992-04-01T23:59:59.000Z

231

Alternative Size and Lifetime Measurements for High-Energy Heavy-Ion Collisions  

E-Print Network (OSTI)

Two-Particle correlations based on the interference of identical particles has provided the chief means for determining the shape and lifetime of sources in relativistic heavy ion collisions. Here, Strong and Coulomb induced correlations are shown to provide equivalent information.

Scott Pratt; Silvio Petriconi

2003-05-07T23:59:59.000Z

232

Joe W. Kwan U.S. Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL)  

E-Print Network (OSTI)

Washington DC December 5, 2012 Heavy Ion Fusion Science Virtual National Laboratory #12;We presented to NAS diameter spot 0.03 J/cm2 (50 ns window) 5.3 J/cm2 (0.6 ns window) Fluence w/in focal radius & FWHM duration

233

Biological and medical research with accelerated heavy ions at the Bevalac, 1977-1980. [Lead abstract  

SciTech Connect

Separate abstracts were prepared for the 46 papers presented in this progress report. This report is a major review of studies with accelerated heavy ions carried out by the Biology and Medicine Division of Lawrence Berkeley Laboratory from 1977 to 1980. (KRM)

Pirruccello, M.C.; Tobias, C.A. (eds.)

1980-11-01T23:59:59.000Z

234

A study of total reaction cross section models used in particle and heavy ion transport codes  

Science Conference Proceedings (OSTI)

Understanding the interactions and propagations of high energy protons and heavy ions are essential when trying to estimate the biological effects of Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE) on personnel in space.12 To be able to calculate ...

L. Sihver; M. Lantz

2011-03-01T23:59:59.000Z

235

T.D. LEE: RELATIVISTIC HEAVY ION COLLISIONS AND THE RIKEN BROOKHAVEN CENTER.  

SciTech Connect

This paper presents the history of Professor T. D. Lee's seminal work on the theory of relativistic heavy ion collisions, and the founding and development of the Riken Brookhaven Center. A number of anecdotes are given about Prof. Lee, and his strong positive effect on his colleagues, particularly young physicists.

MCLERRAN,L.; SAMIOS, N.

2006-11-24T23:59:59.000Z

236

Perturbative probes of QCD matter at the Large Hadron Collider  

E-Print Network (OSTI)

The main results on electroweak probes, jets, high-pT hadrons, heavy-flavour and quarkonia production from the first two years of heavy-ion operation at the Large Hadron Collider (LHC) are briefly reviewed. Data measured at center-of-mass energies sqrt(s_NN) = 2.76 TeV in lead-lead (Pb-Pb) collisions are compared to proton-proton (p-p) measurements in order to extract information on the properties of hot and dense strongly-interacting matter.

David d'Enterria

2012-07-18T23:59:59.000Z

237

Perturbative probes of QCD matter at the Large Hadron Collider  

E-Print Network (OSTI)

The main results on electroweak probes, jets, high-pT hadrons, heavy-flavour and quarkonia production from the first two years of heavy-ion operation at the Large Hadron Collider (LHC) are briefly reviewed. Data measured at center-of-mass energies sqrt(s_NN) = 2.76 TeV in lead-lead (Pb-Pb) collisions are compared to proton-proton (p-p) measurements in order to extract information on the properties of hot and dense strongly-interacting matter.

d'Enterria, David

2012-01-01T23:59:59.000Z

238

Simulation of an RFQ (radio-frequency quadruple) funnel for heavy-ion beams  

Science Conference Proceedings (OSTI)

Use of the magnetic force to focus and deflect heavy-ion beams is marginal at low ion velocities. Low-emittance-growth funnels using discrete magnetic elements are difficult to design for these beams. We show that a new type of radio-frequency quadruple (RFQ) funnel is especially suitable for this application. Simulation procedures, which include space-charge and image effects, have produced a high-quality funnel design for 20-MeV Bi/sup +1/ ions. 4 refs., 4 figs., 2 tabs.

Guy, F.W.; Stokes, R.H.

1989-01-01T23:59:59.000Z

239

Dynamics in the production of superheavy nuclei in low-energy heavy-ion collisions  

E-Print Network (OSTI)

We present a review of the recent progress of theoretical models on the description of the formation of superheavy nuclei in collisions of heavy systems. Two sorts of reactions that are the fusion-evaporation mechanism and the massive damped collisions to produce superheavy nuclei are discussed. Problems and further improvements of the capture of colliding partners, the formation of compound nucleus and the de-excitation process are pointed out. Possible combinations in the synthesis of the gap of the cold fusion and $^{48}$Ca induced reactions are proposed by the calculations based on the dinuclear system model and also compared with other approaches. The synthesis of neutron-rich heavy isotopes near sub-shell closure N=162 via transfer reactions in the damped collisions of two actinides and the influence of shell closure on the production of heavy isotopes are investigated. Prospective possibility to reach superheavy nuclei near N=184 via neutron-rich radioactive beams of high intensity in the future is discussed.

Zhao-Qing Feng; Gen-Ming Jin; Jun-Qing Li

2011-05-26T23:59:59.000Z

240

Trends in Device See Susceptibility from Heavy Ions  

E-Print Network (OSTI)

it-r April, , was in entry in can now ask what parameters or arc to writes in Almost all 1 E 1 soft usually in "write" One or two devices be than preliminary partial data. test is Specific Arrays (GA) `1 1 for arc! in t a show that widely, as" process. gate! array however; `1 several rather hard, soft thresholds and no for including variations, an ONO Applied Laboratory. In has 1 ions (Au and 1) and ions 1. E 1>43 is voltage (5 V). A. Swift (18) permanent failure may from (SE day devices is but attempts to harden Manufacturers arc! with thinner a n d Voltage may more sensitive this is also to 1 Arrays Devices A's were! tested this All fairly soft error an 1 7 `1 A's anti A resistant to 1 data that up hardening used. In but not always It is a of that inclusion not an iron clad guarantee against because the thickness may great for the device. how thin the epi thickness must cannot answered an experimental data it depends intrinsic of in Linear 1 devices have mu

D.K. Nichols; J.R. Coss; K.P. McCarty

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Critical issues for high-brightness heavy-ion beams -- prioritized  

E-Print Network (OSTI)

National Ignition Facility (NIF) will provide motivation toobtaining funding for the NIF, the Large Hadron Collider (

2007-01-01T23:59:59.000Z

242

Heavy ion and proton analysis of a GaAs C-HIGFET SCRAM  

Science Conference Proceedings (OSTI)

The authors present heavy ion and proton upset measurements, including total dose, and displacement damage on a one micron, GaAs, complementary-heterostructure insulated-gate FET (C-HIGFET) 1k x 1 SRAM. SEU characteristics show a two order of magnitude improvement over GaAs MESFET technology. Heavy-ion upset equilibrium measurements show that all cells upset with equal probability at the five percent LET threshold. This indicates that for this device the shape of the cross section versus LET curve is a result of a probability distribution that applies to all cells and is not the result of variations in cell sensitivities. The data set also indicates that the traditional two-dimensional cos([theta]) normalization to LET and fluence are not applicable to this technology.

Cutchin, J.H.; Marshall, P.W.; Weatherford, T.R. (SFA Inc., Landover, MD (United States) Naval Research Lab., Washington, DC (United States)); Langworthy, J.; Petersen, E.L.; Campbell, A.B. (Naval Research Lab., Washington, DC (United States)); Hanka, S.; Peczalski, A. (Honeywell, Inc., Minneapolis, MN (United States))

1993-12-01T23:59:59.000Z

243

A survey of energy loss calculations for heavy ions between 1 and 100 keV  

E-Print Network (OSTI)

The original Lindhard-Scharff-Schitt (LSS) theory and the more recent Tilinin theory for calculating the nuclear and electronic stopping powers of slow heavy ions are compared with predictions from the SRIM code by Ziegler. While little discrepancies are present for the nuclear contribution to the energy loss, large differences are found in the electronic one. When full ion recoil cascade simulations are tested against the elastic neutron scattering data available in the literature, it can be concluded that the LSS theory is the more accurate.

J. Pinto Da Cunha A; P. Sona D

2007-01-01T23:59:59.000Z

244

Biosorption of heavy metal ions to brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida  

SciTech Connect

A fundamental study of the application of brown algae to the aqueous-phase separation of toxic heavy metals was carried out. The biosorption characteristics of cadmium and lead ions were determined with brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida. A metal binding model proposed by the authors was used for the description of metal binding data. The results showed that the biosorption of bivalent metal ions to brown algae was due to bivalent binding to carboxylic groups on alginic acid in brown algae.

Seki, Hideshi; Suzuki, Akira [Hokkaido Univ., Hakodate (Japan)

1998-10-01T23:59:59.000Z

245

Actinide Production in the Reaction of Heavy Ions withCurium-248  

Science Conference Proceedings (OSTI)

Chemical experiments were performed to examine the usefulness of heavy ion transfer reactions in producing new, neutron-rich actinide nuclides. A general quasi-elastic to deep-inelastic mechanism is proposed, and the utility of this method as opposed to other methods (e.g. complete fusion) is discussed. The relative merits of various techniques of actinide target synthesis are discussed. A description is given of a target system designed to remove the large amounts of heat generated by the passage of a heavy ion beam through matter, thereby maximizing the beam intensity which can be safely used in an experiment. Also described is a general separation scheme for the actinide elements from protactinium (Z = 91) to mendelevium (Z = 101), and fast specific procedures for plutonium, americium and berkelium. The cross sections for the production of several nuclides from the bombardment of {sup 248}Cm with {sup 18}O, {sup 86}Kr and {sup 136}Xe projectiles at several energies near and below the Coulomb barrier were determined. The results are compared with yields from {sup 48}Ca and {sup 238}U bombardments of {sup 248}Cm. Simple extrapolation of the product yields into unknown regions of charge and mass indicates that the use of heavy ion transfer reactions to produce new, neutron-rich above-target species is limited. The substantial production of neutron-rich below-target species, however, indicates that with very heavy ions like {sup 136}Xe and {sup 238}U the new species {sup 248}Am, {sup 249}Am and {sup 247}Pu should be produced with large cross sections from a {sup 248}Cm target. A preliminary, unsuccessful attempt to isolate {sup 247}Pu is outlined. The failure is probably due to the half life of the decay, which is calculated to be less than 3 minutes. The absolute gamma ray intensities from {sup 251}Bk decay, necessary for calculating the {sup 251}Bk cross section, are also determined.

Moody, K.J.

1983-07-01T23:59:59.000Z

246

Hydro-inspired parameterizations of freeze-out in relativistic heavy-ion collisions  

E-Print Network (OSTI)

Popular parameterizations of the freeze-out conditions in relativistic heavy-ion collisions are discussed. Similarities and differences between the blast-wave model and the single-freeze-out model, both used recently to interpret the RHIC data, are outlined. A non-boost-invariant extension of the single-freeze-out model is proposed and applied to describe the recent BRAHMS data.

Wojciech Florkowski; Wojciech Broniowski

2004-10-19T23:59:59.000Z

247

Coupled-Channel Effects in Collisions between Heavy Ions near the Coulomb Barrier  

E-Print Network (OSTI)

With the recent availability of state-of-the-art heavy-ion stable and radioactive beams, there has been a renew interest in the investigation of nuclear reactions with heavy ions. I first present the role of inelastic and transfer channel couplings in fusion reactions induced by stable heavy ions. Analysis of experimental fusion cross sections by using standard coupled-channel calculations is discussed. The role of multi-neutron transfer is investigated in the fusion process below the Coulomb barrier by analyzing $^{32}$S+$^{90,96}$Zr as benchmark reactions. The enhancement of fusion cross sections for $^{32}$S+$^{96}$Zr is well reproduced at sub-barrier energies by NTFus code calculations including the coupling of the neutron-transfer channels following the Zagrebaev semi-classical model. Similar effects for $^{40}$Ca+$^{90}$Zr and $^{40}$Ca+$^{96}$Zr fusion excitation functions are found. The breakup coupling in both the elastic scattering and in the fusion process induced by weakly bound stable projectiles is also shown to be crucial. In this lecture, full coupled-channel calculations of the fusion excitation functions are performed by using the breakup coupling for the more neutron-rich reaction and for the more weakly bound projectiles. I clearly demonstrate that Continuum-Discretized Coupled-Channel calculations are capable to reproduce the fusion enhancement from the breakup coupling in $^{6}$Li+$^{59}$Co.

C. Beck

2012-05-21T23:59:59.000Z

248

Coupled-Channel Effects in Collisions between Heavy Ions near the Coulomb Barrier  

E-Print Network (OSTI)

With the recent availability of state-of-the-art heavy-ion stable and radioactive beams, there has been a renew interest in the investigation of nuclear reactions with heavy ions. I first present the role of inelastic and transfer channel couplings in fusion reactions induced by stable heavy ions. Analysis of experimental fusion cross sections by using standard coupled-channel calculations is discussed. The role of multi-neutron transfer is investigated in the fusion process below the Coulomb barrier by analyzing $^{32}$S+$^{90,96}$Zr as benchmark reactions. The enhancement of fusion cross sections for $^{32}$S+$^{96}$Zr is well reproduced at sub-barrier energies by NTFus code calculations including the coupling of the neutron-transfer channels following the Zagrebaev semi-classical model. Similar effects for $^{40}$Ca+$^{90}$Zr and $^{40}$Ca+$^{96}$Zr fusion excitation functions are found. The breakup coupling in both the elastic scattering and in the fusion process induced by weakly bound stable projectiles...

Beck, C

2013-01-01T23:59:59.000Z

249

Heavy Nuclei from RHIC to the Cosmos  

E-Print Network (OSTI)

Ultra-relativistic heavy ion collisions produce a high-temperature, thermalized system that may mimic the conditions present shortly after the big bang. This writeup will given an overview of early results from the Relativistic Heavy Ion Collider (RHIC), and discuss what we have learned about hot, strongly interacting nuclear systems. The thermal and chemical composition of the system will be discussed, along with observables that are sensitive to the early evolution of the system. I will also discuss the implications of the RHIC results for cosmic ray air showers.

Spencer R. Klein

2002-11-01T23:59:59.000Z

250

Overview of Theory and Modeling in the Heavy Ion Fusion Virtual National Laboratory  

Science Conference Proceedings (OSTI)

This paper presents analytical and simulation studies of intense heavy ion beam propagation, including the injection, acceleration, transport and compression phases, and beam transport and focusing in background plasma in the target chamber. Analytical theory and simulations that support the High Current Experiment (HCX), the Neutralized Transport Experiment (NTX), and the advanced injector development program are being used to provide a basic understanding of the nonlinear beam dynamics and collective processes, and to develop design concepts for the next-step Integrated Beam Experiment (IBX), an Integrated Research Experiment (IRE), and a heavy ion fusion driver. Three-dimensional (3-D) nonlinear perturbative simulations have been applied to collective instabilities driven by beam temperature anisotropy and to two-stream interactions between the beam ions and any unwanted background electrons. Three-dimensional particle-in-cell simulations of the 2 MV Electrostatic Quadrupole (ESQ) injector have clarified the influence of pulse rise time. Analytical studies and simulations of the drift compression process have been carried out. Syntheses of a four-dimensional (4-D) particle distribution function from phase-space projections have been developed. And, studies of the generation and trapping of stray electrons in the beam self-fields have been performed. Particle-in-cell simulations, involving preformed plasma, are being used to study the influence of charge and current neutralization on the focusing of the ion beam in Neutralized Transport Experiment and in a fusion chamber.

R.C. Davidson, I.D. Kaganovich, W.W. Lee, H. Qin, E.A. Startsev; S. Tzenov; A. Friedman; J.J. Barnard; R.H. Cohen; D.P. Grote; S.M. Lund; W.M. Sharp; C.M. Celata, M. de Hoon; E. Henestroza; E.P. Lee; S.S. Yu; J.-L. Vay; D.R. Welch; D.V. Rose; C.L. Olson

2003-04-09T23:59:59.000Z

251

Semiconductor detectors for medical tomography with high-energy heavy ions  

SciTech Connect

High-energy heavy ion beams are in use at the Lawrence Berkeley Laboratory for cancer therapy. In order to take full advantage of the very favorable depth-dose characteristics of those beams, it is necessary to determine the stopping characteristics of the ions in the complex media of a human with greater accuracy than obtainable with x-ray CAT scanning. Initial measurements with an array of Si dE/dx position sensitive detectors and a windowless thin planar Ge detector used in a side entry mode show the potential for fabricating an instrument for high accuracy on-line CAT scanning using the same ions to be used for therapy. It is estimated that one tomography can be obtained with a dose of 0.72 Rad-gm.

Llacer, J.; Haller, E.E.; Hansen, W.L.; Walton, J.T.; Batho, E.K.

1980-11-01T23:59:59.000Z

252

High-injection carrier dynamics generated by MeV heavy ions impacting high-speed photodetectors  

Science Conference Proceedings (OSTI)

The generation of single event transients generated by the impact of high-energy ions in high-speed photodetectors leads to bit error rate degradation in optical communications in radiation hard environments such as space. High-energy heavy ions

Jamie Stuart Laird

2005-01-01T23:59:59.000Z

253

Removal of heavy metal ions from oil shale beneficiation process water by ferrite process  

SciTech Connect

The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. (Alabama Univ., University, AL (United States). Mineral Resources Inst.)

1991-01-01T23:59:59.000Z

254

Removal of heavy metal ions from oil shale beneficiation process water by ferrite process  

SciTech Connect

The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. [Alabama Univ., University, AL (United States). Mineral Resources Inst.

1991-12-31T23:59:59.000Z

255

U.S. Heavy Ion Beam Science towards inertial fusion energy  

DOE Green Energy (OSTI)

Significant experimental and theoretical progress in the U.S heavy-ion fusion (HIF) program is reported in modeling and measurements of intense space-charge-dominated heavy ion and electron beams. Measurements of the transport of a well-matched and aligned high current (0.2A) 1.0 MeV potassium ion beam through 10 electric quadrupoles, with a fill factor of 60%, shows no emittance growth within experimental measurement uncertainty, as expected from the simulations. Another experiment shows that passing a beam through an aperture can reduce emittance to near the theoretical limits, and that plasma neutralization of the beam's space-charge can greatly reduce the focal spot radius. Measurements of intense beamlet current density, emittance, charge-state purity, and energy spread from a new, high-brightness, Argon plasma source for HIF experiments are described. New theory and simulations of neutralization of intense beam space charge with plasma in various focusing chamber configurations indicate that near-emittance-limited beam focal spot sizes can be obtained even with beam perveance an order of magnitude higher than in earlier HIF focusing experiments.

Logan, B.G.; Baca, D.; Barnard, J.J.; Bieniosek, F.M.; Burkhart, C.; Celata, C.M.; Chacon-Golcher, E.; Cohen, R.H.; Davidson, R.C.; Efthimion P.; Faltens, A.; Friedman, A.; Grisham, L.; Grote, D.P.; Haber, I.; Henestroza, E.; Kaganovich, I.; Kishek, R.A.; Kwan, J.W.; Lee, E.P.; Lee, W.W.; Leitner, M.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; O'Shea, P.G.; Olson, C.; Olson, R.E.; Prost, L.R.; Qin, H.; Reiser, M.; Rose, D.; Sabbi, G.; Seidl, P.A.; Sharp, W.M.; Shuman, D.B.; Vay, J-L.; Waldron, W.L.; Welch, D.; Westenskow, G.A.; Yu, S.S.

2002-10-01T23:59:59.000Z

256

Muon Collider Papers and Reports  

NLE Websites -- All DOE Office Websites (Extended Search)

of muon collider papers and reports. Muon Collider Feasibilty Study ... Snowmass Book BNL Muon Collider Project Publication Index Fermilab Muon Collider Notes Muon Collider...

257

Fission Decay Widths for Heavy-Ion Fusion-Fission Reactions  

E-Print Network (OSTI)

Cross-section and neutron-emission data from heavy-ion fusion-fission reactions are consistent with a Kramers-modified statistical model which takes into account the collective motion of the system about the ground state; the temperature dependence of the location of fission transition points; and the orientation degree of freedom. We see no evidence to suggest that the nuclear viscosity departs from the surface-plus-window dissipation model. The strong increase in the nuclear viscosity above a temperature of ~1 MeV deduced by others is an artifact generated by an inadequate fission model.

S. G. McCalla; J. P. Lestone

2008-01-30T23:59:59.000Z

258

Modified Fragmentation Function in Heavy Ion Collisions at RHIC via Direct photon-Jet Measurements  

E-Print Network (OSTI)

The presented results are the first measurements at RHIC for direct $\\gamma$-charged hadron azimuthal correlations in heavy ion collisions. We use these correlations to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy (8 $direct photons and photons from the decays of high p$_T$ $\\pi^{0}$. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ trigger at the same centrality class. Within the current uncertainty the I$_{CP}$ of direct $\\gamma$ and $\\pi^{0}$ are similar.

Ahmed M. Hamed

2008-09-08T23:59:59.000Z

259

Estimation of electric conductivity of the quark gluon plasma via asymmetric heavy-ion collisions  

E-Print Network (OSTI)

We show that in asymmetric heavy-ion collisions, especially off-central Cu+Au collisions, a sizable strength of electric field directed from Au nucleus to Cu nucleus is generated in the overlapping region, because of the difference in the number of electric charges between the two nuclei. This electric field would induce an electric current in the matter created after the collision, which result in a dipole deformation of the charge distribution. The directed flow parameters $v_1^{\\pm}$ of charged particles turn out to be sensitive to the charge dipole and provide us with information about electric conductivity of the quark gluon plasma.

Yuji Hirono; Masaru Hongo; Tetsufumi Hirano

2012-11-06T23:59:59.000Z

260

Criterion for the applicability of standard thermodynamics in heavy ion collisions  

Science Conference Proceedings (OSTI)

The use of integrals as approximations for discrete sums in microcanonical equilibrium calculations is valid in the thermodynamic limit. We derive a criterion for testing the validity of this approximation for the relatively small volumes encountered in heavy ion collision fireballs. Numerical examples with CERN and BNL parameters show that there is a real possibility that continuous calculations for the hadronic gas are not accurate. By means of an example, we illustrate the dangers of using canonical and grand canonical methods without first testing whether assumptions underlying their use are valid. Detailed investigations are now required to test the difference between continuous and discrete calculations.

Eggers, H.C.; Heinz, U. (Institut fuer Theoretische Physik, Universitaet Regensburg, Postfach 10 10 42, DW-8400 Regensburg (Germany))

1993-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

The performance of a double sided silicon strip detector as a transmission detector for heavy ions  

E-Print Network (OSTI)

The performance of a double sided silicon strip detector (DSSSD), used for position and energy detection of heavy ions, is reported. The analysis shows that the incomplete charge collection (ICC) and charge sharing (CS) effects of the DSSSD give rise to a loss of energy resolution, however the position information is recorded without ambiguity. Representations of ICC/CS events in the energy spectra are shown and their origins are confirmed by correlation analysis of the spectra from both junction side and ohmic side of the DSSSD.

J L Han; J B Ma; X G Cao; Q Wang; J S Wang; Y Y Yang; P Ma; M R Huang; S L Jin; X J Rong; Z Bai; F Fu; Q Hu; R F Chen; S W Xu; J B Chen; L Jin; Y Li; M H Zhao; H S Xu

2013-07-16T23:59:59.000Z

262

Design and testing of the magnetic quadrupole for the Heavy Ion Fusion Program  

SciTech Connect

The Heavy Ion Fusion Program at the Lawrence Berkeley Laboratory is conducting experiments in the transport and acceleration of ``driverlike`` beams. The single beam coming from the four-to-one beam combiner will be transported in a lattice of pulsed magnetic quadrupoles. The present beam transport consists of high field, short aspect ratio magnetic quadrupoles to maximize the transportable current. This design could also be converted to be superconducting for future uses in a driver. The pulsed quadrupole will develop a maximum field of two Tesla and will be housed within the induction accelerator cells at the appropriate lattice period. Hardware implementation of the physics requirements and full parameter testing is described.

Benjegerdes, R.; Faltens, A.; Fawley, W.; Peters, C.; Reginato, L.; Stuart, M.

1995-04-01T23:59:59.000Z

263

Identity method to study chemical fluctuations in relativistic heavy-ion collisions  

Science Conference Proceedings (OSTI)

Event-by-event fluctuations of the chemical composition of the hadronic final state of relativistic heavy-ion collisions carry valuable information on the properties of strongly interacting matter produced in the collisions. However, in experiments incomplete particle identification distorts the observed fluctuation signals. The effect is quantitatively studied and a new technique for measuring chemical fluctuations, the identity method, is proposed. The method fully eliminates the effect of incomplete particle identification. The application of the identity method to experimental data is explained.

Gazdzicki, Marek; Grebieszkow, Katarzyna; Mackowiak, Maja; Mrowczynski, Stanislaw [Goethe-Universitaet Frankfurt, Max-von-Laue Strasse 1, D-60438 Frankfurt am Main, Germany, and Institute of Physics, Jan Kochanowski University, ul. SwiePtokrzyska 15, PL-25-406 Kielce (Poland); Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, PL-00-662 Warszawa (Poland); Institute of Physics, Jan Kochanowski University, ul. SwiePtokrzyska 15, PL-25-406 Kielce (Poland) and Soltan Institute for Nuclear Studies, ul. Hoza 69, PL-00-681 Warszawa (Poland)

2011-05-15T23:59:59.000Z

264

What have we learned and want to learn from heavy ion collisions at CERN SPS?  

E-Print Network (OSTI)

The talk is a mini-review of the current status of the field, with emphasis on SPS heavy ion program, now and beyond 2000 (as asked by the organizers). The main question is, of course, whether we can convince ourselves and the community at large that the QGP is in fact produced at SPS. We came a long way toward the positive answer, and are definitely on strongly rising part of the learning curve. Still, in few key directions we lack important pieces of evidences.

E. V. Shuryak

1999-06-21T23:59:59.000Z

265

Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction  

SciTech Connect

The scission point in nuclear fission plays a special role where one-body system changes to two-body system. Inverse of this situation is realized in heavy-ion fusion reaction where two-body system changes to one body system. Among several peculiar phenomena expected to occur during this change, we focus our attention to the behavior of compound and fragments shell effects. Some aspects of the interplay between compound and fragments shell effect are discussed related to the topics of the fission valleys in the potential energy surface of actinide nuclei and the fusion-like trajectory found in the cold fusion reaction leading to superheavy nuclei.

Moller, Peter [Los Alamos National Laboratory; Iwamoto, A [JAPAN; Ichikawa, I [JAPAN

2010-09-10T23:59:59.000Z

266

Time-Depentent Hartree-Fock description of heavy ions fusion  

E-Print Network (OSTI)

A microscopic mean-field description of heavy ions fusion is performed in the framework of the Time-Dependent Hartree-Fock (TDHF) theory using a Skyrme interaction with the SLy4d parametrization. A good agreement with experiments is obtained on the position of the fusion barriers for various total masses, mass asymmetries and deformations. The excitation function of the 16O+208Pb is overestimated by about 16% above the barrier. The restriction to an independent particles state in the mean-field dynamics prevents the description of sub-barrier fusion. Effect of transfer on fusion is discussed.

Cdric Simenel; Benot Avez

2007-11-06T23:59:59.000Z

267

Off-momentum dynamic aperture for lattices in the RHIC heavy ion runs  

Science Conference Proceedings (OSTI)

To reduce transverse emittance growth rates from intrabeam scattering in the RHIC heavy ion runs, a lattice with an increased phase advance in the arc FODO cells was adopted in 2008-2011. During these runs, a large beam loss due to limited off-momentum dynamic aperture was observed during longitudinal RF re-bucketing and with transverse cooling. Based on the beam loss observations in the previous ion runs and the calculated off-momentum apertures, we decided to adopt the lattice used before 2008 for the 2012 U-U and Cu-Au runs. The observed beam decay and the measured momentum aperture in the 2012 U-U run are presented.

Luo Y.; Bai, M.; Blaskiewicz, M.; Gu, X.; Fischer, W.; Marusic, A.; Roser, T.; Tepikian, S.; Zhang, S.

2012-05-20T23:59:59.000Z

268

Pre-saddle neutron multiplicity for fission reactions induced by heavy ions and light particles  

E-Print Network (OSTI)

Pre-saddle neutron multiplicity has been calculated for several fission reactions induced by heavy ions and light particles. Experimentally, it is impossible to determine the contribution of neutrons being emitted before the saddle point and those emitted between the saddle and the scission points. Determination of the pre-saddle neutron multiplicity in our research is based on the comparison between the experimental anisotropies and those predicted by the standard saddle-point statistical model. Analysis of the results shows that the pre-saddle neutron multiplicity depends on the fission barrier height and stability of the compound nucleus. In heavy ion induced fission, the number of pre-saddle neutrons decreases with increasing the excitation energy of the compound nucleus. A main cause of this behavior is due to a reduction in the ground state-to-saddle point transition time with increasing the excitation energy of the compound nucleus. Whereas in induced fission by light particles, the number of pre-saddle neutrons increases with increasing the excitation energy of the compound nucleus.

S. Soheyli; M. K. Khalili

2013-06-03T23:59:59.000Z

269

A high-intensity plasma-sputter heavy negative ion source  

SciTech Connect

A multicusp magnetic field plasma surface ion source, normally used for H/sup /minus//ion beam formation, has been modified for the generation of high-intensity, pulsed, heavy negative ion beams suitable for a variety of uses. To date, the source has been utilized to produce mA intensity pulsed beams of more than 24 species. A brief description of the source, and basic pulsed-mode operational data, (e.g., intensity versus cesium oven temperature, sputter probe voltage, and discharge pressure), are given. In addition, illustrative examples of intensity versus time and the mass distributions of ion beams extracted from a number of samples along with emittance data, are also presented. Preliminary results obtained during dc operation of the source under low discharge power conditions suggest that sources of this type may also be used to produce high-intensity (mA) dc beams. The results of these investigations are given, as well, and the technical issues that must be addressed for this mode of operation are discussed. 15 refs., 10 figs., 2 tabs.

Alton, G.D.; Mori, Y.; Takagi, A.; Ueno, A.; Fukumoto, S.

1989-01-01T23:59:59.000Z

270

The european FAZIA initiative: a high-performance digital telescope array for heavy-ion studies  

E-Print Network (OSTI)

The european Fazia collaboration aims at building a new modular array for charged product identification to be employed for heavy-ion studies. The elementary module of the array is a Silicon-Silicon-CsI telescope, optimized for ion identification also via pulse shape analysis. The achievement of top performances imposes specific electronics which has been developed by FAZIA and features high quality charge and current preamplifiers, coupled to fully digital front-end. During the initial R&D phase, original and novel solutions have been tested in prototypes, obtaining unprecedented ion identification capabilities. FAZIA is now constructing a demonstrator array consisting of about two hundreds telescopes arranged in a compact and transportable configuration. In this contribution, we mainly summarize some aspects studied by FAZIA to improve the ion identification. Then we will briefly discuss the FAZIA program centered on experiments to be done with the demonstrator. First results on the isospin dynamics obtained with a reduced set-up demonstrate well the performance of the telescope and represent a good starting point towards future investigations with both stable and exotic beams.

G. Casini; S. Barlini; G. Pasquali; G. Pastore; M. Bini; S. Carboni; A. Olmi; S. Piantelli; G. Poggi; A. Stefanini; S. Valdre'; E. Bonnet; B. Borderie; R. Bougault; M. Bruno; A. Chbihi; M. Cinausero; M. Degerlier; P. Edelbruck; J. D. Frankland; F. Gramegna; D. Gruyer; M. Guerzoni; A. Kordjasz; T. Kozik; N. Le Neindre; O. Lopez; T. Marchi; P. Marini; L. Morelli; A. Ordine; M. Parlog; M. F. Rivet; E. Rosato; F. Salomon; G. Spadaccini; T. Twarog; E. Vient; M. Vigilante

2013-09-05T23:59:59.000Z

271

Incorporation of the effect of the composite electric fields of molecular ions as a simulation tool for biological damage due to heavy-ion irradiation  

Science Conference Proceedings (OSTI)

This paper presents a theoretical study of the DNA damage due to the effect of the composite electric fields of H{sub 2}O{sup +} ions produced from the irradiation of a heavy ion onto a cell. A model for atomic and molecular processes in strong electric fields is developed. It is found that the composite electric fields increase the number of events of electron-impact ionization processes. This may promote DNA damage.

Moribayashi, Kengo [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 8-1-7 Umemidai, Kizugawa-City, Kyoto 619-0215 (Japan) and Faculty of Life and Medical Sciences, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, Kyoto 610-0394 (Japan)

2011-07-15T23:59:59.000Z

272

Swift heavy-ion irradiation-induced shape and structural transformation in cobalt nanoparticles  

Science Conference Proceedings (OSTI)

The shape and structural evolution of Co nanoparticles embedded in SiO{sub 2} and subjected to swift heavy-ion irradiation have been investigated over a wide energy and fluence range. Modifications of the nanoparticle size and shape were characterized with transmission electron microscopy and small-angle x-ray scattering. Nanoparticles below a threshold diameter remained spherical in shape and progressively decreased in size under irradiation due to dissolution. Nanoparticles above the threshold diameter transformed into nanorods with their major dimension parallel to the incident ion direction. Modifications of the atomic-scale structure of the Co nanoparticles were identified with x-ray absorption spectroscopy. Analysis of the x-ray absorption near-edge spectra showed that prior to irradiation all Co atoms were in a metallic state, while after irradiation Co atoms were in both oxidized and metallic environments, the former consistent with dissolution. The evolution of the nanoparticle short-range order was determined from extended x-ray absorption fine structure spectroscopy. Structural changes in the Co nanoparticles as a function of ion fluence included an increase in disorder and asymmetric deviation from a Gaussian interatomic distance distribution coupled with a decrease in bondlength. Such changes resulted from the irradiation-induced decrease in nanoparticle size and subsequent dissolution.

Sprouster, D.J.; Giulian, R.; Araujo, L.L.; Kluth, P.; Johannessen, B.; Cookson, D.J.; Ridgway, M.C. (Aust. Synch.); (ANU)

2012-02-07T23:59:59.000Z

273

Melting of Dense Hydrogen during Heavy Ion Beam-Driven Compression  

DOE Green Energy (OSTI)

Until now the thermodynamic and structural properties of hydrogen continue to be understood unsatisfactory. A number of complex high pressure phases at relatively low temperatures has been confirmed [1]. However, conclusive answers on the existence of a plasma phase transition, the dissociation of hydrogen molecules at high densities, the metallization in the solid, and the melting line for pressures above 70GPa are still missing. A particularly interesting behavior has been predicted for the melting line at high pressures where it has a maximum and its slope changes sign [2]. In Ref. [3], we have shown that these states can be created using cylindrical compression driven by heavy ion beams. Employing ab initio simulations [4] and experimental data, a new wide range equation of state for hydrogen was constructed [3]. This new hydrogen EOS combined with hydrodynamic simulations is then used to describe the compression of hydrogen in LAPLAS targets [5] driven by heavy ion beams to be generated at the FAIR. The results shown in Fig. 1 indicate that the melting line up to its maximum as well as the transition from molecular fluids to fully ionized plasmas can be tested. By carefully tuning the number of particles in the beam, the compression can be adjusted to yield states at the solid-liquid phase transition (compare panels (a) and (b) in Fig. 1). This allows one to test the shape of the melting line beyond its maximum. It was demonstrated [3] that x-ray scattering [6] can be used to distinguish between the molecular solid and liquid phases as well as the metallic states. Hydrodynamic simulations have also highlighted the importance of temperature diagnostics, as it is more sensitive to the EOS than the density based diagnostic methods. Different materials have been considered as absorber. Although lead might seem to be the natural choice, the simulations show that aluminium is also a feasible option if slightly less compression is sufficient. Moreover, aluminium offers further options for testing by x-ray scattering and, thus, might be favorable compared to lead drivers. In summary, valuable information on the properties of high-density hydrogen can be obtained by dynamic compression with heavy ion beams. The long standing questions of the plasma phase transition, melting, and metallization can be addressed. The calculated Jupiter isentrope shown in Fig. 1 indicates that such experiments would be also highly beneficial for the giant planet modeling.

Grinenko, A; Gericke, D O; Vorberger, J; Glenzer, S H

2009-03-02T23:59:59.000Z

274

Dynamical approach to heavy-ion induced fusion using actinide target  

Science Conference Proceedings (OSTI)

To treat heavy-ion reactions using actinide target nucleus, we propose a model which takes into account the coupling to the collective states of interacting nuclei in the penetration of the Coulomb barrier and the dynamical evolution of nuclear shape from the contact configuration. A fluctuation-dissipation model (Langevin equation) was applied in the dynamical calculation, where effect of nuclear orientation at the initial impact on the prolately deformed target nucleus was considered. Using this model, we analyzed the experimental data for the mass distribution of fission fragments (MDFF) in the reaction of {sup 36}S+{sup 238}U at several incident energies. Fusion-fission, quasifission and deep-quasi-fission are separated as different trajectories on the potential energy surface. We estimated the fusion cross section of the reaction.

Aritomo, Y.; Hagino, K.; Chiba, S.; Nishio, K. [Flerov Laboratory of Nuclear Reactions, JINR, Dubna, 141980 (Russian Federation); Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550 (Japan); Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195 (Japan)

2012-10-20T23:59:59.000Z

275

Jozso's Legacy Chemical and Kinetic Freeze-out in Heavy-Ion Collisions  

E-Print Network (OSTI)

We review J. Zimanyi's key contributions to the theoretical understanding of dynamical freeze-out in nuclear collisions and their subsequent applications to ultra-relativistic heavy-ion collisions, leading to the discovery of a freeze-out hierarchy where chemical freeze-out of hadron yields precedes the thermal decoupling of their momentum spectra. Following Zimanyi's lines of reasoning we show that kinetic freeze-out necessarily leads to a dependence of the corresponding freeze-out temperature on collision centrality. This centrality dependence can be predicted within hydrodynamic models, and for Au+Au collisions at RHIC this prediction is shown to reproduce the experimentally observed centrality dependence of the thermal decoupling temperature, extracted from hadron momentum spectra. The fact that no such centrality dependence is observed for the chemical decoupling temperature, extracted from the hadron yields measured in these collisions, excludes a similar kinetic interpretation of the chemical decouplin...

Heinz, U

2008-01-01T23:59:59.000Z

276

Photon HBT interferometry for non-central heavy-ion collisions  

E-Print Network (OSTI)

Currently, the only known way to obtain experimental information about the space-time structure of a heavy-ion collision is through 2-particle momentum correlations. Azimuthally sensitive HBT interferometry (Hanbury Brown-Twiss intensity interferometry) can complement elliptic flow measurements by constraining the spatial deformation of the source and its time evolution. Performing these measurements on photons allows us to access the fireball evolution at earlier times than with hadrons. Using ideal hydrodynamics to model the space-time evolution of the collision fireball, we explore theoretically various aspects of 2-photon intensity interferometry with transverse momenta up to 2 GeV, in particular the azimuthal angle dependence of the HBT radii in non-central collisions. We highlight the dual nature of thermal photon emission, in both central and non-central collisions, resulting from the superposition of QGP and hadron resonance gas photon production. This signature is present in both the thermal photon s...

Frodermann, Evan

2009-01-01T23:59:59.000Z

277

Heavy Ion Beam in Resolution of the Critical Point Problem for Uranium and Uranium Dioxide  

E-Print Network (OSTI)

Important advantages of heavy ion beam (HIB) irradiation of matter are discussed in comparison with traditional sources - laser heating, electron beam, electrical discharge etc. High penetration length (~ 10 mm) is of primary importance for investigation of dense matter properties. This gives an extraordinary chance to reach the uniform heating regime when HIB irradiation is being used for thermophysical property measurements. Advantages of HIB heating of highly-dispersive samples are claimed for providing free and relatively slow quasi-isobaric heating without fast hydrodynamic expansion of heated sample. Perspective of such HIB application are revised for resolution of long-time thermophysical problems for uranium and uranium-bearing compounds (UO2). The priorities in such HIB development are stressed: preferable energy levels, beam-time duration, beam focusing, deposition of the sample etc.

Igor Iosilevskiy; Victor Gryaznov

2010-05-23T23:59:59.000Z

278

Strangeness Production close to Threshold in Proton-Nucleus and Heavy-Ion Collisions  

E-Print Network (OSTI)

We discuss strangeness production close to threshold in p+A and A+A collision. Comparing the body of available K+, K0, K-, and Lambda data with the IQMD transport code and for some key observables as well with the HSD transport code, we find good agreement for the large majority of the observables. The investigation of the reaction with help of these codes reveals the complicated interaction of the strange particles with hadronic matter which makes strangeness production in heavy-ion collisions very different from that in elementary interactions. We show how different strange particle observables can be used to study the different facets of this interaction (production, rescattering and potential interaction) which finally merge into a comprehensive understanding of these interactions. We identify those observables which allow for studying (almost) exclusively one of these processes to show how future high precision experiments can improve our quantitative understanding. Finally, we discuss how the K+ multipl...

Hartnack, Christoph; Leifels, Yvonne; Bratkovskaya, Elena L; Aichelin, Jrg

2011-01-01T23:59:59.000Z

279

Alternative Scenarios of Relativistic Heavy-Ion Collisions: I. Baryon Stopping  

E-Print Network (OSTI)

Simulations of relativistic heavy-ion collisions within the three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS involving deconfinement transition are presented. The latter are an EoS with the first-order phase transition and that with a smooth crossover transition. The model setup is described in detail. The analysis is performed in a wide range of incident energies 2.7 GeV $energy. Results on proton and net-proton rapidity distributions are reported. Comparison with available data indicate certain preference of the crossover EoS. It is found that predictions within deconfinement-transition scenarios exhibit a "peak-dip-peak-dip" irregularity in the incident energy dependence of the form of the net-proton rapidity distributions in central collisions. This irregularity is a signal of deconfinement onset occurring in the hot and dense stage of the nuclear collision.

Yu. B. Ivanov

2013-02-23T23:59:59.000Z

280

Relativistic heavy ion physics. Progress report, November 15, 1992--November 14, 1993  

SciTech Connect

This is a progress report for the period May 1992 through April 1993. The first section, entitled ``Purpose and Trends, gives background on the recent trends in the research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled ``Physics Research Progress``, is divided into four parts: participation in the program to develop a large detector named PHENIX for the RHIC accelerator; joining E864 at the AGS accelerator and the role in that experiment; progress made in the study of electromagnetic dissociation highlight of this endeavor is an experiment carried out with the {sup 197}Au beam from the AGS accelerator in April 1992; progress in completion of the nuclear structure studies. In the final section a list of publications, invited talks, and contributed talks is given.

Hill, J.C.; Wohn, F.K.

1993-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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281

Dynamic Stabilization of the Ablative Rayleigh-Taylor Instability for Heavy Ion Fusion  

SciTech Connect

Dynamic stabilization of the ablative Rayleigh-Taylor instability of a heavy ion fusion target induced by a beam wobbling system is studied. Using a sharp-boundary model and Courant-Synder theory, it is shown, with an appropriately chosen modulation waveform, that the instability can be sta- bilized in certain parameter regimes. It is found that the stabilization e ect has a strong dependence on the modulation frequency and the waveform. Modulation with frequency comparable to the instability growth rate is the most e ective in terms of stabilizing the instability. A modulation with two frequency components can result in a reduction of the growth rate larger than the sum of that due to the two components when applied separately.

Hong Qin, Ronald C. Davidson and B. Grant Logan

2012-10-04T23:59:59.000Z

282

Energy loss in high energy heavy ion collisions from the Hydro+Jet model  

E-Print Network (OSTI)

We investigate the effect of energy loss of jets in high energy heavy ion collisions by using a full three-dimensional space-time evolution of a fluid combined with (mini-)jets that are explicitly evolved in space-time. In order to fit the pi^0 data for the Au+Au collisions at sqrt(s_{NN}) = 130 GeV, the space-time averaged energy loss dE/dx(tau energy loss occurs at the very early time less than 2 fm/c in the QGP phase and that energy loss in the mixed phase is negligible within our parameterization for jet energy loss. This is a consequence of strong expansion of the system.

Hirano, T; Hirano, Tetsufumi; Nara, Yasushi

2002-01-01T23:59:59.000Z

283

ACE/SWICS OBSERVATIONS OF HEAVY ION DROPOUTS WITHIN THE SOLAR WIND  

SciTech Connect

We present the first in situ observations of heavy ion dropouts within the slow solar wind, observed for select elements ranging from helium to iron. For iron, these dropouts manifest themselves as depletions of the Fe/H ratio by factors up to {approx}25. The events often exhibit mass-dependent fractionation and are contained in slow, unsteady wind found within a few days from known stream interfaces. We propose that such dropouts are evidence of gravitational settling within large coronal loops, which later undergo interchange reconnection and become source regions of slow, unsteady wind. Previously, spectroscopic studies by Raymond et al. in 1997 (and later Feldman et al. in 1999) have yielded strong evidence for gravitational settling within these loops. However, their expected in situ signature plasma with heavy elements fractionated by mass was not observed prior to this study. Using data from the SWICS instrument on board the Advanced Composition Explorer (ACE), we investigate the composition of the solar wind within these dropouts and explore long term trends over most of a solar cycle.

Weberg, Micah J. [PhD Candidate in Space and Planetary Physics, 2435 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Zurbuchen, Thomas H. [Professor, Space Science and Aerospace Engineering, Associate Dean for Entrepreneurship, 2429 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Lepri, Susan T., E-mail: mjweberg@umich.edu, E-mail: thomasz@umich.edu, E-mail: slepri@umich.edu [Associate Research Scientist, 2417 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States)

2012-11-20T23:59:59.000Z

284

A systematic study of actinide production from the interactions of heavy ions with sup 248 Cm  

Science Conference Proceedings (OSTI)

Production cross sections for heavy actinides produced from the interactions of {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca ions with {sup 248}Cm were measured at energies ranging from 0.98 to 1.35 X Coulomb barrier. The recoiling reaction products were collected in copper or gold catcher foils located near the {sup 248}Cm target. Separate fractions of Bk, Cf, Es, Fm, and Md were obtained from a radiochemical separation procedure. For the {sup 12}C system, a He/KCl jet was used to transport the recoiling No activities of interest to a rotating wheel system. The isotopic distributions of the actinide products were found to be essentially symmetric about the maximum with full-widths-at-half-maximum of approximately 2.5 mass units. Isotopic distributions of the {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca systems were found to be very similar to the {sup 40,48}Ca systems studied previously. The maxima of the isotopic distributions generally occurred for those reaction channels which involved the exchange of the fewest number of nucleons between the target and projectile for which the calculated excitation energy was a positive quantity. Additionally, the maxima of the excitation functions occurred at those projectile energies which were consistent with the calculated reaction barriers based upon a binary reaction mechanism. The experimental data from the four systems investigated were compared to several models of heavy ion interactions including a damped reaction mechanism, compound nucleus formation and subsequent particle evaporation, and classical partial wave calculations for binary systems.

Leyba, J.D.

1990-09-07T23:59:59.000Z

285

System Size and Energy Dependence of Dilepton Production in Heavy-Ion Collisions at SIS Energies  

E-Print Network (OSTI)

We study the dilepton production in heavy-ion collisions at energies of 1-2 AGeV as well as in proton induced pp, pn, pd and p+A reactions from 1 GeV up to 3.5 GeV. For the analysis we employ three different transport models - the microscopic off-shell Hadron-String-Dynamics (HSD) transport approach, the Isospin Quantum Molecular Dynamics (IQMD) approach as well as the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) approach. We confirm the experimentally observed enhancement of the dilepton yield (normalized to the multiplicity of neutral pions $N_{\\pi^0}$) in heavy-ion collisions with respect to that measured in $NN = (pp+pn)/2$ collisions. We identify two contributions to this enhancement: a) the $pN$ bremsstrahlung which scales with the number of collisions and not with the number of participants, i.e. pions; b) the dilepton emission from intermediate $\\Delta$'s which are part of the reaction cycles $\\Delta \\to \\pi N ; \\pi N \\to \\Delta$ and $NN\\to N\\Delta; N\\Delta \\to NN$. With increasing system size more generations of intermediate $\\Delta$'s are created. If such $\\Delta$ decays into a pion, the pion can be reabsorbed, however, if it decays into a dilepton, the dilepton escapes from the system. Thus, experimentally one observes only one pion (from the last produced $\\Delta$) whereas the dilepton yield accumulates the contributions from all $\\Delta$'s of the cycle. We show as well that the Fermi motion enhances the production of pions and dileptons in the same way. Furthermore, employing the off-shell HSD approach, we explore the influence of in-medium effects like the modification of self-energies and spectral functions of the vector mesons due to their interactions with the hadronic environment.

E. L. Bratkovskaya; J. Aichelin; M. Thomere; S. Vogel; M. Bleicher

2013-01-04T23:59:59.000Z

286

Relics of Minijets amid Anisotropic Flows in High-energy Heavy-ion Collisions  

E-Print Network (OSTI)

Two dimensional low-$p_T$ dihadron correlations in azimuthal angle $\\phi$ and pseudo-rapidity $\\eta$ in high-energy heavy-ion collisions are investigated within both the HIJING Monte Carlo model and an event-by-event (3+1)D ideal hydrodynamic model. Without final-state interaction and collective expansion, dihadron correlations from HIJING simulations have a typical structure from minijets that contains a near-side two-dimensional peak and an away-side ridge along the $\\eta$-direction. In contrast, event-by-event (3+1)D ideal hydrodynamic simulations with fluctuating initial conditions from the HIJING+AMPT model produce a strong dihadron correlation that has an away-side as well as a near-side ridge. Relics of intrinsic dihadron correlation from minijets in the initial conditions still remain as superimposed on the two ridges. By varying initial conditions from HIJING+AMPT, we study effects of minijets, non-vanishing initial flow and longitudinal fluctuation on the final state dihadron correlations. With a large rapidity gap, one can exclude near-side correlations from minijet relics and dihadron correlations can be described by the superposition of harmonic flows up to the 6th order. When long-range correlations with a large rapidity gap are subtracted from short-range correlations with a small rapidity gap, the remaining near-side dihadron correlations result solely from relics of minijets. Low transverse momentum hadron yields per trigger ($p_T^{\\rm trig} <4$ GeV/$c$, $p_T^{\\rm asso}<2$ GeV/$c$) in central heavy-ion collisions are significantly enhanced over that in p+p collisions while widths in azimuthal angle remain the same, in qualitative agreement with experimental data.

Longgang Pang; Qun Wang; Xin-Nian Wang

2013-09-26T23:59:59.000Z

287

Integrated Experimental and Computational Approach to Understand the Effects of Heavy Ion Radiation on Skin Homeostasis.  

SciTech Connect

The effects of low dose high linear energy transfer (LET) radiation on human health are of concern for both space and clinical exposures. As epidemiological data for such radiation exposures are scarce for making relevant predictions, we need to understand the mechanism of response especially in normal tissues. Our objective here is to understand the effects of heavy ion radiation on tissue homeostasis in a realistic model system. Towards this end, we exposed an in vitro three dimensional skin equivalent to low fluences of Neon (Ne) ions (300 MeV/u), and determined the differentiation profile as a function of time following exposure using immunohistochemistry. We found that Ne ion exposures resulted in transient increases in the tissue regions expressing the differentiation markers keratin 10, and filaggrin, and more subtle time-dependent effects on the number of basal cells in the epidermis. We analyzed the data using a mathematical model of the skin equivalent, to quantify the effect of radiation on cell proliferation and differentiation. The agent-based mathematical model for the epidermal layer treats the epidermis as a collection of heterogeneous cell types with different proliferation/differentiation properties. We obtained model parameters from the literature where available, and calibrated the unknown parameters to match the observed properties in unirradiated skin. We then used the model to rigorously examine alternate hypotheses regarding the effects of high LET radiation on the tissue. Our analysis indicates that Ne ion exposures induce rapid, but transient, changes in cell division, differentiation and proliferation. We have validated the modeling results by histology and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The integrated approach presented here can be used as a general framework to understand the responses of multicellular systems, and can be adapted to other epithelial tissues.

von Neubeck, Claere; Shankaran, Harish; Geniza, Matthew; Kauer, Paula M.; Robinson, Robert J.; Chrisler, William B.; Sowa, Marianne B.

2013-08-08T23:59:59.000Z

288

Study of heavy ion induced fission fragment angular and mass distribution at near and sub-coulomb barrier energies  

E-Print Network (OSTI)

The thesis presents investigations on the angular and mass distribution of fission fragments on heavy ion induced fission reactions. The present investigations address current issues in heavy ion induced fission reactions like finding the optimum entrance channel for the synthesis of super heavy elements (SHE). A double arm time of flight spectrometer over long flight path was used to measure the precise masses of complementary fission fragments. Necessary large area position sensitive gas detectors, the method of experiments and data analysis were developed. The first string of measurements were for a spherical target (209^Bi) with oxygen and fluorine projectiles. The next series of experiments were done using a deformed target (232^Th) with fluorine, oxygen and carbon projectiles.

T. K. Ghosh

2005-08-10T23:59:59.000Z

289

Development of a Micromegas TPC for Low Energy Heavy Ions Measurement for Nuclear Fission and Astrophysics Applications  

SciTech Connect

Time Projection Chambers are widely used since many years for tracking and identification of charged particles in high energy physics. We present a new R and D project to investigate the feasibility of a Micromegas TPC for low energy heavy ions detection. Two physics cases are relevant for this project. The first is the study of the nuclear fission of actinides by measuring the fission fragments properties (mass, nuclear charge, kinetic energy) that will be performed at different installations and in particular at the NFS facility to be built in the framework of the SPIRAL2 project in GANIL. The second physics case is the study of heavy ion reactions, like ({alpha},{gamma}), ({alpha},p), ({alpha},n) and all the inverse reactions in the energy range between 1.5 and 3 AMeV using both stable and radioactive beams. These reactions have a key role in p process in nuclear astrophysics to explain the synthesis of heavy proton-rich nuclei. Within the project, a large effort is devoted to Monte-Carlo simulations and a detailed benchmark of different simulation codes on the energy loss and range in gas of heavy ions at low energy has been performed. A new approach for simulating the ion charge state evolution in GEANT4 is also presented. Finally, preliminary results of an experimental test campaign on prototype are discussed.

Panebianco, S.; Dore, D.; Giomataris, I.; Papaevangelou, Th.; Vernoud, L. [CEA, Centre de Saclay, Institut de Recherche sur les lois Fondamentales de l' Univers, 91191 Gif-sur-Yvette (France); Axiotis, M.; Fanourakis, G.; Geralis, Th.; Harissopoulos, S.; Lagoyannis, A. [Institute of Nuclear Physics, NCRS ' Demokritos' , 15310 Aghia Paraskevi, Athens (Greece)

2011-10-28T23:59:59.000Z

290

Simulation and Analysis of Human Phantoms Exposed to Heavy Charged Particle Irradiations Using the Particle and Heavy Ion Transport System (PHITS)  

E-Print Network (OSTI)

Anthropomorphic phantoms are commonly used for testing radiation fields without the need to expose human subjects. One of the most widely known is RANDO phantom. This phantom is used primarily for medical X-ray applications, but a similar design known as "MATROSHKA" is now being used for space research and exposed to heavy ion irradiations from the Galactic environment. Since the radiation field in the phantom should respond in a similar manner to how it would act in human tissues and organs under an irradiation, the tissue substitute chosen for soft tissue and the level of complexity of the entire phantom are crucial issues. The phantoms, and the materials used to create them, were developed mainly for photon irradiations and have not been heavily tested under the conditions of heavy ion exposures found in the space environment or external radiotherapy. The Particle and Heavy-Ion Transport code System (PHITS) was used to test the phantoms and their materials for their potential as human surrogates for heavy ion irradiation. Stopping powers and depth-dose distributions of heavy charged particles (HCPs) important to space research and medical applications were first used in the simulations to test the suitability of current soft tissue substitutes. A detailed computational anthropomorphic phantom was then developed where tissue substitutes and ICRU-44 tissue could be interchanged to verify the validation of the soft tissue substitutes and and determine the required level of complexity of the entire phantom needed to achieve a specified precision as a replacement of the human body. The materials tested were common soft tissue substitutes in use and the materials which had a potential for the soft tissue substitute. Ceric sulfate dosimeter solution was closest to ICRU-44 tissue; however, it was not appropriate as the phantom material because it was a solution. A150 plastic, ED4C (fhw), Nylon (Du Pont Elvamide 8062), RM/SR4, Temex, and RW-2 were within 1% of the mean normalized difference of mass stopping powers (or stopping powers for RW-2) when compared to the ICRU-44 tissue, and their depth-dose distributions were close; therefore, they were the most suitable among the remaining solid materials. Overall, the soft tissue substitutes which were within 1% of ICRU-44 tissue in terms of stopping power produced reasonable results with respect to organ dose in the developed phantom. RM/SR4 is the best anthropomorphic phantom soft tissue substitute because it has similar interaction properties and identical density with ICRU-44 tissue and it is a rigid solid polymer giving practical advantages in manufacture of real phantoms.

Lee, Dongyoul

2011-12-01T23:59:59.000Z

291

Muon Collider History  

NLE Websites -- All DOE Office Websites (Extended Search)

Colliders: A Brief History Below is a brief potted history of the muon collider concept. Click here for a one transparency summary. The muon collider concept is an idea dating back...

292

A very thin havar film vacuum window for heavy ions to perform radiobiology studies at the BNL Tandem  

Science Conference Proceedings (OSTI)

Heavy ion beams from the BNL Tandem Van de Graaff accelerators will be made available for radiobiology studies on cell cultures. Beam energy losses need to be minimized both in the vacuum window and in the air in order to achieve the ranges required for the cells to be studied. This is particularly challenging for ions heavier than iron. The design is presented of a 0.4-inch diameter Havar film window that will satisfy these requirements. Films as thin as 80 microinches were successfully pressure tested. The final thickness to be used may be slightly larger to help in achieving pin hole free windows. We discuss design considerations and present pressure and vacuum test results as well as tests with heavy ion beams.

Thieberger, P.; Abendroth, H.; Alessi, J.; Cannizzo, L.; Carlson, C.; Gustavsson, A.; Minty, M.; Snydstrup, L.

2011-03-28T23:59:59.000Z

293

Incorporation of the effect of the composite electric fields of molecular ions as a simulation tool for biological damage due to heavy ion irradiation II  

SciTech Connect

This paper presents a theoretical study of the DNA damage due to the effect of the composite electric fields of H{sub 2}O{sup +} ions produced from the irradiation of a heavy ion onto a cell. It is found that a much larger number of electrons, which are produced from electron impact ionization, is trapped near the track of an incident ion in the case of C{sup 6+} ion irradiation with the energy of 3 MeV/u than that of proton irradiation. Therefore, the irradiation of carbon ions may produce a larger number of cluster DNA damage than that in the irradiation of protons. This may lead to the understanding of relative biological effectiveness (RBE).

Moribayashi, Kengo [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 8-1-7, Umemidai, Kizugawa-city, 619-0215 (Japan) and Faculty of Life and Medical Sciences, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, 610-0394 (Japan)

2012-07-11T23:59:59.000Z

294

Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields  

E-Print Network (OSTI)

of positive and negative chlorine ions, with only a smalltest case. We chose chlorine because, unlike iodine orTwo sets of experiments with chlorine using different RF ion

Kwan, J.W.

2008-01-01T23:59:59.000Z

295

Physics implications of correlation data from the RHIC and LHC heavy-ion programs  

E-Print Network (OSTI)

Two-dimensional angular correlation data from the STAR experiment at RHIC and from the LHC experiments provide critical information about dynamical processes in relativistic heavy-ion collisions. The principal correlation structures of interest are a broad jet-related peak at small relative azimuth ($\\phi$) extending to large relative pseudorapidity ($\\eta$), the dijet ridge at large relative azimuth, and an independent double ridge on $\\phi$ represented by a quadrupole function. The broad peak at small relative azimuth has been attributed, in large part, to initial-state fluctuations and hydrodynamic flow which produce higher-order harmonics on $\\phi$. That conjecture is challenged in this paper. It is shown that the net effect of additional higher harmonic model elements is to describe small, non-Gaussian (NG) shapes in the broad jet-related peak. The quadrupole correlation, which is also conventionally attributed to hydrodynamic flow, is considered within the Balitsky - Fadin - Kuraev - Lipatov (BFKL) Pomeron framework. Preliminary results using this model for the quadrupole correlation for particle production from 200 GeV $p+p$ collisions are shown to be consistent with recent data from STAR.

R. L. Ray

2013-11-04T23:59:59.000Z

296

RHIC PERFORMANCE DURING THE FY10 200 GeV Au+Au HEAVY ION RUN  

SciTech Connect

Since the last successful RHIC Au+Au run in 2007 (Run-7), the RHIC experiments have made numerous detector improvements and upgrades. In order to benefit from the enhanced detector capabilities and to increase the yield of rare events in the acquired heavy ion data a significant increase in luminosity is essential. In Run-7 RHIC achieved an average store luminosity of = 12 x 10{sup 26} cm{sup -2} s{sup -1} by operating with 103 bunches (out of 111 possible), and by squeezing to {beta}* = 0.85 m. This year, Run-10, we achieved = 20 x 10{sup 26} cm{sup -2} s{sup -1}, which put us an order of magnitude above the RHIC design luminosity. To reach these luminosity levels we decreased {beta}* to 0.75 m, operated with 111 bunches per ring, and reduced longitudinal and transverse emittances by means of bunched-beam stochastic cooling. In addition we introduced a lattice to suppress intra-beam scattering (IBS) in both RHIC rings, upgraded the RF control system, and separated transition crossing times in the two rings. We present an overview of the changes and the results of Run-10 performance.

Brown, K.A.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.; Bruno, D.; Carlson, C.; Connolly, R.; de Maria, R.; DOttavio, T.; Drees, A.; Fischer, W.; Fu, W.; Gardner, C.; Gassner, D.; Glenn, J.W.; Hao, Y.; Harvey, M.; Hayes, T.; Hoff, L.; Huang, H.; Laster, J.; Lee, R.; Litvinenko, V.; Luo, Y.; MacKay, W.; Marr, G.; Marusic, A.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Oerter, B.; Pilat, F.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Russo, T.; Sampson, P.; Sandberg, J.; Satogata, T.; Severino, F.; Schoefer, V.; Schultheiss, C.; Smith, K.; Steski, D.; Tepikian, S.; Theisen, C.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; Wilinski, M.; Zaltsman, A.; Zeno, K.; Zhang, S.Y.

2010-05-23T23:59:59.000Z

297

RHIC PERFORMANCE DURING THE FY10 200 GeV Au+Au HEAVY ION RUN  

Science Conference Proceedings (OSTI)

Since the last successful RHIC Au+Au run in 2007 (Run-7), the RHIC experiments have made numerous detector improvements and upgrades. In order to benefit from the enhanced detector capabilities and to increase the yield of rare events in the acquired heavy ion data a significant increase in luminosity is essential. In Run-7 RHIC achieved an average store luminosity of = 12 x 10{sup 26} cm{sup -2} s{sup -1} by operating with 103 bunches (out of 111 possible), and by squeezing to {beta}* = 0.85 m. This year, Run-10, we achieved = 20 x 10{sup 26} cm{sup -2} s{sup -1}, which put us an order of magnitude above the RHIC design luminosity. To reach these luminosity levels we decreased {beta}* to 0.75 m, operated with 111 bunches per ring, and reduced longitudinal and transverse emittances by means of bunched-beam stochastic cooling. In addition we introduced a lattice to suppress intra-beam scattering (IBS) in both RHIC rings, upgraded the RF control system, and separated transition crossing times in the two rings. We present an overview of the changes and the results of Run-10 performance.

Brown, K.A.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.; Bruno, D.; Carlson, C.; Connolly, R.; de Maria, R.; DOttavio, T.; Drees, A.; Fischer, W.; Fu, W.; Gardner, C.; Gassner, D.; Glenn, J.W.; Hao, Y.; Harvey, M.; Hayes, T.; Hoff, L.; Huang, H.; Laster, J.; Lee, R.; Litvinenko, V.; Luo, Y.; MacKay, W.; Marr, G.; Marusic, A.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Oerter, B.; Pilat, F.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Russo, T.; Sampson, P.; Sandberg, J.; Satogata, T.; Severino, F.; Schoefer, V.; Schultheiss, C.; Smith, K.; Steski, D.; Tepikian, S.; Theisen, C.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; Wilinski, M.; Zaltsman, A.; Zeno, K.; Zhang, S.Y.

2010-05-23T23:59:59.000Z

298

Effects of Minijets on Common Observables in Heavy-Ion Collisions with Uncommon Implications  

E-Print Network (OSTI)

In this brief review of the observable effects of minijets in heavy-ion collisions the main points emphasized are that the quadruple moment $v_2(p_T,b)$ and the hadronic ($\\pi$ and $p$) spectra at low $p_T$ can both be reproduced by minijet contributions to the recombination of thermal and shower partons. Without using hydrodynamics the minijet approach does not trace the evolution of the expanding system. The thermal distribution of the medium partons at the time of hadronization is assumed, but rapid thermalization initially is not required so as to allow minijets to leave their footprints on the system in the final state. Azimuthal anisotropy due to minijets is directly calculated in the momentum space without any fluid assumption relating the spatial eccentricity to $v_2$. There are no more parameters used, compared to the hydro approach in fitting the data on $v_2$ and $p_T$ spectra. Thus both approaches satisfy the sufficiency condition for a viable description of the dynamical process involved.

Rudolph C. Hwa

2013-02-14T23:59:59.000Z

299

Particle production in strong electromagnetic fields in relativistic heavy-ion collisions  

E-Print Network (OSTI)

I review the origin and properties of electromagnetic fields produced in heavy ion collisions. The field strength immediately after a collision is proportional to the collision energy and reaches eB\\sim(m_\\pi)^2 at RHIC and eB\\sim10 (m_\\pi)^2 at LHC. I demonstrate by explicit analytical calculation that after dropping by about one-two orders of magnitude during the first fm/c of plasma expansion, it freezes out and lasts for as long as quark-gluon plasma exists as a consequence of finite electrical conductivity of the plasma. Magnetic field breaks spherical symmetry in the direction perpendicular to the reaction plane and therefore all kinetic coefficients are anisotropic. I examine viscosity of QGP and show that magnetic field induces azimuthal anisotropy on plasma flow even in spherically symmetric geometry. Very strong electromagnetic field has an important impact on particle production. I discuss the problem of energy loss and polarization of fast fermions due to synchrotron radiation, consider photon decay induced by magnetic field, elucidate J/Psi dissociation via Lorentz ionization mechanism and examine electromagnetic radiation by plasma. I conclude that all processes in QGP are affected by strong electromagnetic field and call for experimental investigation.

Kirill Tuchin

2013-01-01T23:59:59.000Z

300

Detection Efficiency of a ToF Spectrometer from Heavy-Ion Elastic Recoil Detection  

SciTech Connect

The detection efficiency of a time-of-flight system based on two micro-channel plates (MCP) time zero detectors plus a conventional silicon surface barrier detector was obtained from heavy ion elastic recoil measurements (this ToF spectrometer is mainly devoted to measurements of total fusion cross section of weakly bound projectiles on different mass-targets systems). In this work we have used beams of {sup 7}Li, {sup 16}O, {sup 32}S and {sup 35}Cl to study the mass region of interest for its application to measurements fusion cross sections in the {sup 6,7}Li+{sup 27}Al systems at energies around and above the Coulomb barrier (0.8V{sub B{<=}}E{<=}2.0V{sub B}). As the efficiency of a ToF spectrometer is strongly dependent on the energy and mass of the detected particles, we have covered a wide range of the scattered particle energies with a high degree of accuracy at the lowest energies. The different experimental efficiency curves obtained in that way were compared with theoretical electronic stopping power curves on carbon foils and were applied.

Barbara, E. de; Marti, G. V.; Capurro, O. A.; Fimiani, L.; Mingolla, M. G. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); Negri, A. E.; Arazi, A.; Figueira, J. M.; Pacheco, A. J.; Martinez Heimann, D.; Carnelli, P. F. F. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); CONICET, Av. Rivadavia 1917, C1033AAJ Ciudad Autonoma de Buenos Aires (Argentina); Fernandez Niello, J. O. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); CONICET, Av. Rivadavia 1917, C1033AAJ Ciudad Autonoma de Buenos Aires (Argentina); Universidad Nacional de General San Martin, Ayacucho 2197, B1650BWA Partido de San Martin, Provincia de Buenos Aires (Argentina)

2010-08-04T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Photon HBT interferometry for non-central heavy-ion collisions  

E-Print Network (OSTI)

Currently, the only known way to obtain experimental information about the space-time structure of a heavy-ion collision is through 2-particle momentum correlations. Azimuthally sensitive HBT interferometry (Hanbury Brown-Twiss intensity interferometry) can complement elliptic flow measurements by constraining the spatial deformation of the source and its time evolution. Performing these measurements on photons allows us to access the fireball evolution at earlier times than with hadrons. Using ideal hydrodynamics to model the space-time evolution of the collision fireball, we explore theoretically various aspects of 2-photon intensity interferometry with transverse momenta up to 2 GeV, in particular the azimuthal angle dependence of the HBT radii in non-central collisions. We highlight the dual nature of thermal photon emission, in both central and non-central collisions, resulting from the superposition of QGP and hadron resonance gas photon production. This signature is present in both the thermal photon source function and the HBT radii extracted from Gaussian fits of the 2-photon correlation function.

Evan Frodermann; Ulrich Heinz

2009-07-07T23:59:59.000Z

302

Jozso's Legacy: Chemical and Kinetic Freeze-out in Heavy-Ion Collisions  

E-Print Network (OSTI)

We review J. Zimanyi's key contributions to the theoretical understanding of dynamical freeze-out in nuclear collisions and their subsequent applications to ultra-relativistic heavy-ion collisions, leading to the discovery of a freeze-out hierarchy where chemical freeze-out of hadron yields precedes the thermal decoupling of their momentum spectra. Following Zimanyi's lines of reasoning we show that kinetic freeze-out necessarily leads to a dependence of the corresponding freeze-out temperature on collision centrality. This centrality dependence can be predicted within hydrodynamic models, and for Au+Au collisions at RHIC this prediction is shown to reproduce the experimentally observed centrality dependence of the thermal decoupling temperature, extracted from hadron momentum spectra. The fact that no such centrality dependence is observed for the chemical decoupling temperature, extracted from the hadron yields measured in these collisions, excludes a similar kinetic interpretation of the chemical decoupling process. We argue that the chemical decoupling data from Au+Au collisions at RHIC can only be consistently understood if the chemical freeze-out process is driven by a phase transition, and that the measured chemical decoupling temperature therefore measures the critical temperature of the quark-hadron phase transition. We propose additional experiments to further test this interpretation.

Ulrich W. Heinz; Gregory Kestin

2007-09-21T23:59:59.000Z

303

Energy deposition in hard dihadron triggered events in heavy-ion collisions  

E-Print Network (OSTI)

The experimental observation of hadrons correlated back-to-back with a (semi-)hard trigger in heavy ion collisions has revealed a splitting of the away side correlation structure in a low to intermediate transverse momentum (P_T) regime. This is consistent with the assumption that energy deposited by the away side parton into the bulk medium produced in the collision excites a sonic shockwave (a Mach cone) which leads to away side correlation strength at large angles. A prediction following from assuming such a hydrodynamical origin of the correlation structure is that there is a sizeable elongation of the shockwave in rapidity due to the longitudinal expansion of the bulk medium. Using a single hadron trigger, this cannot be observed due to the unconstrained rapidity of the away side parton. Using a dihadron trigger, the rapidity of the away side parton can be substantially constrained and the longitudinal structure of the away side correlation becomes accessible. However, in such events several effects occur which change the correlation structure substantially: There is not only a sizeable contribution due to the fragmentation of the emerging away side parton, but also a systematic bias towards small energy deposition into the medium and hence a weak shockwave. In this paper, both effects are addressed.

Thorsten Renk

2008-04-08T23:59:59.000Z

304

THERMINATOR 2: THERMal heavy IoN generATOR 2  

E-Print Network (OSTI)

We present an extended version of THERMINATOR, a Monte Carlo event generator dedicated to studies of the statistical production of particles in relativistic heavy-ion collisions. The increased functionality of the code contains the following features: The input of any shape of the freeze-out hypersurface and the expansion velocity field, including the 3+1 dimensional profiles, in particular those generated externally with various hydrodynamic codes. The hypersufraces may have variable thermal parameters, which allows for studies departing significantly from the mid-rapidity region, where the baryon chemical potential becomes large. We include a library of standard sets of hypersurfaces and velocity profiles describing the RHIC Au+Au data at sqrt(s_(NN)) = 200 GeV for various centralities, as well as those anticipated for the LHC Pb+Pb collisions at sqrt(s_(NN)) = 5.5 TeV. A separate code, FEMTO-THERMINATOR, is provided to carry out the analysis of femtoscopic correlations which are an important source of info...

Chojnacki, Mikolaj; Florkowski, Wojciech; Broniowski, Wojciech

2012-01-01T23:59:59.000Z

305

Adiabatic Heavy Ion Fusion Potentials for Fusion at Deep Sub-barrier Energies  

E-Print Network (OSTI)

The fusion cross sections from well above barrier to extreme sub-barrier energies have been analysed using the energy (E) and angular momentum (L) dependent barrier penetration model ({\\small{ELDBPM}}). From this analysis, the adiabatic limits of fusion barriers have been determined for a wide range of heavy ion systems. The empirical prescription of Wilzynska and Wilzynski has been used with modified radius parameter and surface tension coefficient values consistent with the parameterization of the nuclear masses. The adiabatic fusion barriers calculated from this prescription are in good agreement with the adiabatic barriers deduced from {\\small{ELDBPM}} fits to fusion data. The nuclear potential diffuseness is larger at adiabatic limit, resulting in a lower $\\hbar\\omega$ leading to increase of "logarithmic slope" observed at energies well below the barrier. The effective fusion barrier radius and curvature values are anomalously smaller than the predictions of known empirical prescriptions. A detailed comparison of the systematics of fusion barrier with and without L-dependence has been presented.

S. V. S. Sastry; S. Kailas; A. K. Mohanty; A. Saxena

2003-11-12T23:59:59.000Z

306

Isospin-dependent pion in-medium effects on the charged-pion ratio in heavy ion collisions  

E-Print Network (OSTI)

Using results from the chiral perturbation theory for the s-wave interaction and the Delta-resonance model for the p-wave interaction of pions with nucleons, we evaluated the spectral functions of pions in asymmetric nuclear matter with unequal proton and neutron densities. We find that in hot dense neutron-rich matter the strength of the spectral function of positively charged pions at low energies is somewhat larger than that of negatively charged pions. In a thermal model, this isospin-dependent effect slightly reduces the ratio of negatively charged to positively charged pions that are produced in heavy ion collisions induced by radioactive beams. The relevance of our results to the determination of the nuclear symmetry energy from the measured ratio of negatively to positively charged pions produced in heavy ion collisions is discussed.

Xu, Jun; Ko, Che Ming; Oh, Yongseok.

2010-01-01T23:59:59.000Z

307

Heavy ion SEU immunity of a GaAs complementary HIGFET circuit fabricated on a low temperature grown buffer layer  

SciTech Connect

The authors compare dynamic SEU characteristics of GaAs complementary HIGFET devices fabricated on conventional semi-insulating substrates versus low temperature grown GaAs (LT GaAs) buffer layers. Heavy ion test results on shift register and flip-flop devices from the same process lot demonstrate that the LT GaAs layer provides immunity from upsets, even at an LET value of 90 MeV {center_dot} cm{sup 2}/mg. This result is also consistent with pulsed laser measurements performed on the same flip-flop circuits used in the ion test.

Marshall, P.W.; Weatherford, T.; Carts, M. [Naval Research Lab., Washington, DC (United States)]|[SFA, Inc., Landover, MD (United States); Dale, C.J.; McMorrow, D. [Naval Research Lab., Washington, DC (United States); Peczalski, A.; Baier, S.; Nohava, J.; Skogen, J. [Honeywell Systems and Research Center, Bloomington, MN (United States)

1995-12-01T23:59:59.000Z

308

Turbulent pattern formation and diffusion in the early-time dynamics in the relativistic heavy-ion collision  

E-Print Network (OSTI)

We propose a picture of turbulent pattern formation in the relativistic heavy-ion collision, which follows an efficient process to break color strings and dispose energy in the whole phase space. We perform numerical simulations using the SU(2) pure Yang-Mills theory in a non-expanding box to observe a dynamical phenomenon in the transverse plane akin to the domain growth in time-dependent spin systems.

Kenji Fukushima

2013-07-03T23:59:59.000Z

309

Proceedings of RIKEN BNL Research Center Workshop entitled Hydrodynamics in Heavy Ion Collisions and QCD Equation of State (Volume 88)  

SciTech Connect

The interpretation of relativistic heavy-ion collisions at RHIC energies with thermal concepts is largely based on the relative success of ideal (nondissipative) hydrodynamics. This approach can describe basic observables at RHIC, such as particle spectra and momentum anisotropies, fairly well. On the other hand, recent theoretical efforts indicate that dissipation can play a significant role. Ideally viscous hydrodynamic simulations would extract, if not only the equation of state, but also transport coefficients from RHIC data. There has been a lot of progress with solving relativistic viscous hydrodynamics. There are already large uncertainties in ideal hydrodynamics calculations, e.g., uncertainties associated with initial conditions, freezeout, and the simplified equations of state typically utilized. One of the most sensitive observables to the equation of state is the baryon momentum anisotropy, which is also affected by freezeout assumptions. Up-to-date results from lattice quantum chromodynamics on the transition temperature and equation of state with realistic quark masses are currently available. However, these have not yet been incorporated into the hydrodynamic calculations. Therefore, the RBRC workshop 'Hydrodynamics in Heavy Ion Collisions and QCD Equation of State' aimed at getting a better understanding of the theoretical frameworks for dissipation and near-equilibrium dynamics in heavy-ion collisions. The topics discussed during the workshop included techniques to solve the dynamical equations and examine the role of initial conditions and decoupling, as well as the role of the equation of state and transport coefficients in current simulations.

Karsch,F.; Kharzeev, D.; Molnar, K.; Petreczky, P.; Teaney, D.

2008-04-21T23:59:59.000Z

310

Dependence of asymmetries for charge distribution with respect to the reaction plane on initial energy in heavy ion collisions  

E-Print Network (OSTI)

In the paper two combinations of correlators are defined in order to investigate the evolution of possible $\\mathcal{P/CP}$ invariance violation in strong interactions with initial energy for heavy ion collisions. These combinations correspond to absolute and relative asymmetry of distribution of electrically charge particles with respect to the reaction plane in heavy ion collisions. Energy dependence of the parameters was derived from data of STAR and ALICE experiments. Significant decreasing both absolute and relative asymmetry is observed at energies $\\sqrt{s_{NN}} < 20$ GeV. This feature agrees qualitatively with other results of stage-I beam energy scan program in STAR experiment. General behavior of dependence of absolute asymmetry on initial energy agree reasonably with behavior of similar dependence of Chern -- Simons diffusion rate calculated at different values of external Abelian magnetic field. The observed behavior of understudying parameters vs energy can be considered as indication on possible transition to predominance of hadronic states over quark-gluon degrees of freedom in the mixed phase created in heavy ion collisions at intermediate energies.

V. A. Okorokov

2013-01-05T23:59:59.000Z

311

A new solar flare heavy ion model and its implementation through MACREE, an improved modeling tool to calculate single event effect rates in space  

Science Conference Proceedings (OSTI)

A new solar flare heavy ion model has been developed to support Space Station Single Event Effects (SEE) evaluations. It shows good agreement with previous flare data, and is implemented through an improved version of the CREME code.

Majewski, P.P.; Normand, E.; Oberg, D.L. [Boeing Defense and Space Group, Seattle, WA (United States)] [Boeing Defense and Space Group, Seattle, WA (United States)

1995-12-01T23:59:59.000Z

312

Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields  

E-Print Network (OSTI)

pos itive and ne gative chlorine i ons, w ith onl y a s malltest case. W e ch ose chlorine b ecause, u nlike iodine o rsets of e xperiments with chlorine using different RF ion s

Grisham, L. R.

2010-01-01T23:59:59.000Z

313

A 16 MeV/nucleon cocktail for heavy ion testing  

E-Print Network (OSTI)

early 1990s, a second-generation ion source was built at thethe first third generation ECR ion source being built in thenewest generations of chips. Once the VENUS ion source is

2004-01-01T23:59:59.000Z

314

SPALLATION-FISSION COMPETITION IN ASTATINE COMPOUND NUCLEI FORMED BY HEAVY-ION BOMBARDMENT  

E-Print Network (OSTI)

Effect of Angular Momentum on Fission Probability (Thesis),R. Vandenbosch, Nuclear Fission, to be published in Nuclearfrom Heavy-lon-Induced Fission (Thesis), Lawrence Radiation

Thomas, T. Darrah; Gordon, Glen E.; Latimer, Robert M.; Seaborg, Glenn T.

2008-01-01T23:59:59.000Z

315

Fully integrated transport approach to heavy ion reactions with an intermediate hydrodynamic stage  

E-Print Network (OSTI)

We present a coupled Boltzmann and hydrodynamics approach to relativistic heavy ion reactions. This hybrid approach is based on the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) transport approach with an intermediate hydrodynamical evolution for the hot and dense stage of the collision. Event-by-event fluctuations are directly taken into account via the non-equilibrium initial conditions generated by the initial collisions and string fragmentations in the microscopic UrQMD model. After a (3+1)-dimensional ideal hydrodynamic evolution, the hydrodynamical fields are mapped to hadrons via the Cooper-Frye equation and the subsequent hadronic cascade calculation within UrQMD proceeds to incorporate the important final state effects for a realistic freeze-out. This implementation allows to compare pure microscopic transport calculations with hydrodynamic calculations using exactly the same initial conditions and freeze-out procedure. The effects of the change in the underlying dynamics - ideal fluid dynamics vs. non-equilibrium transport theory - will be explored. The freeze-out and initial state parameter dependences are investigated for different observables. Furthermore, the time evolution of the baryon density and particle yields are discussed. We find that the final pion and proton multiplicities are lower in the hybrid model calculation due to the isentropic hydrodynamic expansion while the yields for strange particles are enhanced due to the local equilibrium in the hydrodynamic evolution. The results of the different calculations for the mean transverse mass excitation function, rapidity and transverse mass spectra for different particle species at three different beam energies are discussed in the context of the available data.

Hannah Petersen; Jan Steinheimer; Gerhard Burau; Marcus Bleicher; Horst Stcker

2008-06-10T23:59:59.000Z

316

Nonperturbative enhancement of heavy quark-pair production in a strong SU(2) color field  

Science Conference Proceedings (OSTI)

Nonperturbative charm and bottom quark-pair production is investigated in the early stage of heavy-ion collisions. The time-dependent study is based on a kinetic description of fermion-pair production in strong non-Abelian fields. We introduce a time-dependent chromo-electric external field with a pulselike time evolution to simulate the overlap of two colliding heavy ions. The calculations is performed in a SU(2) color model with finite current quark masses. Yields of heavy quark pairs are compared to the ones of light and strange quark pairs. We show that the small inverse duration time of the field pulse determines the efficiency of the quark-pair production. The expected suppression for heavy quark production, as follows from the Schwinger formula for a constant field, is not seen, but rather an enhanced heavy quark production appears at ultrarelativistic energies.

Levai, Peter; Skokov, Vladimir [KFKI RMKI Research Institute for Particle and Nuclear Physics, P.O. Box 49, Budapest 1525 (Hungary); Gesellschaft fuer Schwerionenforschung mbH, Planckstr. 1, D-64291 Darmstadt (Germany)

2010-10-01T23:59:59.000Z

317

Cryogenic studies for the proposed CERN large hadron electron collider (LHEC)  

Science Conference Proceedings (OSTI)

The LHeC (Large Hadron electron Collider) is a proposed future colliding beam facility for lepton-nucleon scattering particle physics at CERN. A new 60 GeV electron accelerator will be added to the existing 27 km circumference 7 TeV LHC for collisions of electrons with protons and heavy ions. Two basic design options are being pursued. The first is a circular accelerator housed in the existing LHC tunnel which is referred to as the "Ring-Ring" version. Low field normal conducting magnets guide the particle beam while superconducting (SC) RF cavities cooled to 2 K are installed at two opposite locations at the LHC tunnel to accelerate the beams. For this version in addition a 10 GeV re-circulating SC injector will be installed. In total four refrigerators with cooling capacities between 1.2 kW and 3 kW @ 4.5 K are needed. The second option

2012-01-01T23:59:59.000Z

318

Solenoid transport of a heavy ion beam for warm dense matterstudies and inertial confinement fusion  

SciTech Connect

From February to July 2006, I have been doing research as a guest at Lawrence Berkeley National Laboratory (LBNL), in the Heavy Ion Fusion group. This internship, which counts as one semester in my master's program in France, I was very pleased to do it in a field that I consider has the beauty of fundamental physics, and at the same time the special appeal of a quest for a long-term and environmentally-respectful energy source. During my stay at LBNL, I have been involved in three projects, all of them related to Neutralized Drift Compression Experiment (NDCX). The first one, experimental and analytical, has consisted in measuring the effects of the eddy currents induced by the pulsed magnets in the conducting plates of the source and diagnostic chambers of the Solenoid Transport Experiment (STX, which is a subset of NDCX). We have modeled the effect and run finite-element simulations that have reproduced the perturbation to the field. Then, we have modified WARP, the Particle-In-Cell code used to model the whole experiment, in order to import realistic fields including the eddy current effects and some details of each magnet. The second project has been to take part in a campaign of WARP simulations of the same experiment to understand the leakage of electrons that was observed in the experiment as a consequence to some diagnostics and the failure of the electrostatic electron trap. The simulations have shown qualitative agreement with the measured phenomena, but are still in progress. The third project, rather theoretical, has been related to the upcoming target experiment of a thin aluminum foil heated by a beam to the 1-eV range. At the beginning I helped by analyzing simulations of the hydrodynamic expansion and cooling of the heated material. But, progressively, my work turned into making estimates for the nature of the liquid/vapor two-phase flow. In particular, I have been working on criteria and models to predict the formation of droplets, their size, and their partial or total evaporation in the expanding flow.

Armijo, Julien

2006-10-01T23:59:59.000Z

319

Non-collective excitations in low-energy heavy-ion reactions: applicability of the random-matrix model  

E-Print Network (OSTI)

We investigate the applicability of a random-matrix model to the description of non-collective excitations in heavy-ion reactions around the Coulomb barrier. To this end, we study fusion in the reaction $^{16}$O + $^{208}$Pb, taking account of the known non-collective excitations in the $^{208}$Pb nucleus. We show that the random-matrix model for the corresponding couplings reproduces reasonably well the exact calculations, obtained using empirical deformation parameters. This implies that the model may provide a powerful method for systems in which the non-collective couplings are not so well known.

S. Yusa; K. Hagino; N. Rowley

2013-08-29T23:59:59.000Z

320

Hadron Colliders and Hadron Collider Physics Symposium  

E-Print Network (OSTI)

This article summarizes main developments of the hadron colliders and physics results obtained since their inception around forty years ago. The increase in the collision energy of over two orders of magnitude and even larger increases in luminosity provided experiments with unique data samples. Developments of full acceptance detectors, particle identification and analysis methods provided fundamental discoveries and ultra-precise measurements which culminated in the completion and in depth verification of the Standard Model. Hadron Collider Physics symposium provided opportunities for those working at hadron colliders to share results of their research since 1979 and helped greatly to develop the field of particle physics.

Denisov, Dmitri

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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321

Status of Trapped-Ion Physics in Europe  

Science Conference Proceedings (OSTI)

... Innsbruck molecular ions spectroscopy K. Wendt Mainz heavy ions laser ion sources ... K. Wendt Mainz heavy ions laser ion sources W. Quint ...

2011-03-01T23:59:59.000Z

322

Dilepton Spectroscopy of QCD Matter at Collider Energies  

E-Print Network (OSTI)

Low-mass dilepton spectra as measured in high-energy heavy-ion collisions are a unique tool to obtain spectroscopic information about the strongly interacting medium produced in these reactions. Specifically, in-medium modifications of the vector spectral function, which is well known in the vacuum, can be deduced from the thermal radiation off the expanding QCD fireball. This, in particular, allows to investigate the fate of the $\\rho$ resonance in the dense medium, and possibly infer from it signatures of the (partial) restoration of chiral symmetry, which is spontaneously broken in the QCD vacuum. After briefly reviewing calculations of thermal dilepton emission rates from hot QCD matter, utilizing effective hadronic theory, lattice QCD or resummed perturbative QCD, we focus on applications to dilepton spectra at heavy-ion collider experiments at RHIC and LHC. This includes invariant-mass spectra at full RHIC energy with transverse-momentum dependencies and azimuthal asymmetries, as well as a systematic investigation of the excitation function down to fixed-target energies, thus making contact to previous precision measurements at the SPS. Furthermore, predictions for the energy frontier at the LHC are presented in both dielectron and dimuon channels.

Ralf Rapp

2013-04-08T23:59:59.000Z

323

Studies of heavy-ion reactions and transuranic nuclei. Progress report, September 1, 1992--August 31, 1993  

SciTech Connect

This report contain papers on the following topics: The Cold-Fusion Saga; Decay Patterns of Dysprosium Nuclei Produced in {sup 32}S + {sup 118,124}Sn Fusion Reactions; Unexpected Features of Reactions Between Very Heavy Ions at Intermediate Bombarding Energies; Correlations Between Neutrons and Charged Products from the Dissipative Reaction {sup 197}Au+{sup 208}Pb at E/A = 29 MeV; Dissipative Dynamics of Projectile-Like Fragment Production in the Reaction {sup 209}Bi+{sup 136}Xe at E/A = 28.2 MeV; Dynamical Production of Intermediate-Mass Fragments in Peripheral {sup 209}Bi+{sup 136}Xe Collisions at E{sub lab}/A = 28.2 MeV; The Rochester 960-Liter Neutron Multiplicity Meter; A Simple Pulse Processing Concept for a Low-Cost Pulse-Shape-Based Particle Identification; A One-Transistor Preamplifier for PMT Anode Signals; A Five-Channel Multistop TDC/Event Handler for the SuperBall Neutron Multiplicity Meter; Construction of the SuperBall -- a 16,000-Liter Neutron Detector for Calorimetric Studies of Intermediate-Energy Heavy-Ion Reactions; A Computer Code for Light Detection Efficiency Calculations for Photo-multipliers of a Neutron Detector; Evaluation of Gd-Loaded Liquid Scintillators for the SuperBall Neutron Calorimeter; and Measurement of the Interaction of Cosmic-Ray {mu}{sup {minus}} with a Muon Telescope.

Schroeder, W.U.

1993-08-01T23:59:59.000Z

324

Fermilab | Muon Collider | Graphics  

NLE Websites -- All DOE Office Websites (Extended Search)

Graphics A chain of accelerators and other devices is necessary to produce and accelerate muons before scientists can make muons collide. Click image for larger version A muon...

325

Experimental investigation and thermodynamic modeling of extraction of heavy metal ions from aqueous solutions by chelation in supercritical carbon dioxide  

E-Print Network (OSTI)

Wastewater streams containing heavy metals are common in industry. To prevent the contamination of clean water sources, the Clean Water Act specifies limits on the heavy metal concentrations of industrial waste water. This creates a strong need for developing cost effective and environmentally friendly metal removal technologies. Solvent extraction has been recognized as one of the best methods for removing metals from wastewater. Although the metals are easily removed, this process has two major disadvantages. First, the solvent/metal solution must be subsequently purified. Second, since the solvent may be miscible in the aqueous phase, the residual solvent must be removed from the water stream. These disadvantages can be eliminated by substituting conventional organic solvents with supercritical fluids. The main objective of this research has been to investigate the potential and feasibility of heavy metal ion extraction through chelation in supercritical CO2. Copper has been chosen as the model contaminant as it is frequently found in industrial waste streams. Different chelating agents have been tested to find the most appropriate one for copper. Analytical methods have been developed to quantify supercritical and aqueous phase compositions. Specifically, an Atomic Absorption Analyzer and a Gas Chromatograph have been employed. Copper ions have been successfully extracted up to 97% on different isotherms. Considering the phase equilibria and the thirteen reactions taking place in the system, a thermodynamic model has been developed. This model predicts the system pH which is a important factor in design of metal extraction units. With the model the efficiency of the extraction with different chelating agents at different temperatures and pressures is easily estimated. The model is also capable of calculating the concentrations of chemical species present in the system. This study proposed a novel and viable technique for the remediation of metal ions in waste water streams. In conjunction with the developed model the efficiency of this process for a specific industrial application can be accurately estimated. The results of this study demonstrate that this process is both environmentally friendly and economically feasible for wide spread industrial use.

Uyansoy, Hakki

1995-01-01T23:59:59.000Z

326

Ion-driver fast ignition: Reducing heavy-ion fusion driver energy and cost, simplifying chamber design, target fab, tritium fueling and power conversion  

DOE Green Energy (OSTI)

Ion fast ignition, like laser fast ignition, can potentially reduce driver energy for high target gain by an order of magnitude, while reducing fuel capsule implosion velocity, convergence ratio, and required precisions in target fabrication and illumination symmetry, all of which should further improve and simplify IFE power plants. From fast-ignition target requirements, we determine requirements for ion beam acceleration, pulse-compression, and final focus for advanced accelerators that must be developed for much shorter pulses and higher voltage gradients than today's accelerators, to deliver the petawatt peak powers and small focal spots ({approx}100 {micro}m) required. Although such peak powers and small focal spots are available today with lasers, development of such advanced accelerators is motivated by the greater likely efficiency of deep ion penetration and deposition into pre-compressed 1000x liquid density DT cores. Ion ignitor beam parameters for acceleration, pulse compression, and final focus are estimated for two examples based on a Dielectric Wall Accelerator; (1) a small target with {rho}r {approx} 2 g/cm{sup 2} for a small demo/pilot plant producing {approx}40 MJ of fusion yield per target, and (2) a large target with {rho}r {approx} 10 g/cm{sup 2} producing {approx}1 GJ yield for multi-unit electricity/hydrogen plants, allowing internal T-breeding with low T/D ratios, >75 % of the total fusion yield captured for plasma direct conversion, and simple liquid-protected chambers with gravity clearing. Key enabling development needs for ion fast ignition are found to be (1) ''Close-coupled'' target designs for single-ended illumination of both compressor and ignitor beams; (2) Development of high gradient (>25 MV/m) linacs with high charge-state (q {approx} 26) ion sources for short ({approx}5 ns) accelerator output pulses; (3) Small mm-scale laser-driven plasma lens of {approx}10 MG fields to provide steep focusing angles close-in to the target (built-in as part of each target); (4) beam space charge-neutralization during both drift compression and final focus to target. Except for (1) and (2), these critical issues may be explored on existing heavy-ion storage ring accelerator facilities.

Logan, G.; Callahan-Miller, D.; Perkins, J.; Caporaso, G.; Tabak, M.; Moir, R.; Meier, W.; Bangerter, Roger; Lee, Ed

1998-04-01T23:59:59.000Z

327

THE CLASSICAL-LIMIT S-MATRIX FOR HEAVY ION SCATTERING  

E-Print Network (OSTI)

probabilities are sensi nuclear interference ve to Coulomb-now feel the nuclear one would expect ve to the nuclearncl us ion a complex nuclear potential. ve using t integral

Donangelo, R.J.

2010-01-01T23:59:59.000Z

328

Next Linear Collider Home Page  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome to the Next Linear Collider NLC Home Page If you would like to learn about linear colliders in general and about this next-generation linear collider project's mission,...

329

Papers on Muon Colliders  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnets for Muon Collider and Neutrino Storage Ring Magnets for Muon Collider and Neutrino Storage Ring (and Open Midplane Dipole for LARP): R. Gupta, et al., "High Field HTS Solenoid for a Muon Collider – Demonstrations, Challenges and Strategies, MT23, July 2013", presented at MT23, (talk) R. Weggel et al., "Open Midplane Dipoles for Muon Collider", 2011 Particle Accelerator Conference, New York (POSTER).. R. Gupta, M. Anerella, A. Ghosh, H. Kirk, R. Palmer, S. Plate, W. Sampson, Y. Shiroyanagi, P. Wanderer, B. Brandt, D. Cline, A. Garren, J. Kolonko, R. Scanlan, R. Weggel, "High field HTS R&D solenoid for muon collider", 2010 Applied Superconductivity Conference, Washington, DC, August 2010 >> Y. Shiroyanagi, W. Sampson, A. Ghosh, R. Gupta, "The Construction and

330

Temperature determined by isobaric yield ratio in heavy-ion collisions  

E-Print Network (OSTI)

This work focuses on the study of temperature associated with the final heavy fragments in reactions induced by both the neutron-proton symmetric and the neutron-rich projectiles, and with incident energy ranges from 60$A$ MeV to 1$A$ GeV. Isobaric yield ratio (IYR) is used to determine the temperature of heavy fragments. Cross sections of measured fragment in reactions are analyzed, and a modified statistical abrasion-ablation (SAA) model is used to calculate the yield of fragment in 140$A$ MeV $^{64}$Ni + $^{9}$Be and 1$A$ GeV $^{136}$Xe + $^{208}$Pb reactions. Relatively low $T$ of heavy fragments are obtained in different reactions ($T$ ranges from 1 to 3MeV). $T$ is also found to depend on the neutron-richness of the projectile. The incident energy affects $T$ very little. $\\Delta\\mu/T$ (the ratio of the difference between the chemical potential of neutron and proton to temperature) is found to increase linearly as $N/Z$ of projectile increases. It is found that $T$ of the $^{48}$Ca reaction, for which IYRs are of $A<50$ isobars, is affected greatly by the temperature-corrected $\\Delta B(T)$. But $T$ of reactions using IYRs of heavier fragments are only slightly affected by the temperature-corrected $\\Delta B(T)$. The SAA model analysis gives a consistent overview of the results extracted in this work. $T$ from IYR, which is for secondary fragment, is different from that of the hot emitting source. $T$ and $\\Delta\\mu$ are essentially governed by the sequential decay process.

C. W. Ma; J. Pu; Y. G. Ma; R. Wada; S. S. Wang

2012-12-01T23:59:59.000Z

331

High intensity production of high and medium charge state uraniumand other heavy ion beams with VENUS  

SciTech Connect

The next generation, superconducting ECR ion source VENUS(Versatile ECR ion source for NUclear Science) started operation with 28GHzmicrowave heating in 2004. Since then it has produced world recordion beam intensities. For example, 2850 e mu A of O6+, 200 e mu A of U33+or U34+, and in respect to high charge state ions, 1 e mu A of Ar18+, 270e mu A of Ar16+, 28 e mu A of Xe35+ and 4.9 e mu A of U47+ have beenproduced. A brief overview of the latest developments leading to theserecord intensities is given and the production of high intensity uraniumbeams is discussed in more detail.

Leitner, Daniela; Galloway, Michelle L.; Loew, Timothy J.; Lyneis, Claude M.; Rodriguez, Ingrid Castro; Todd, Damon S.

2007-11-15T23:59:59.000Z

332

Probing High-Velocity Transient-Field Strength Using Heavy-ions Traversing Fe and Gd  

SciTech Connect

The transient field strength for {sup 76}Ge ions, passing through iron and gadolinium layers at velocities approxZv{sub 0}, has been measured. Although a sizeable value has been obtained for Gd, a vanishing strength has been observed in Fe.

Fiori, E.; Georgiev, G.; Cabaret, S.; Lozeva, R. [CSNSM, CNRS/IN2P3, Universite Paris-Sud 11, UMR8609, F-91405 ORSAY-Campus (France); Stuchbery, A. E. [Department of Nuclear Physics, Australian National University, Canberra (Australia); Jungclaus, A.; Modamio, V.; Walker, J. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Balabanski, D. L. [INRNE-BAS, Sofia (Bulgaria); Blazhev, A. [IKP, Cologne (Germany); Clement, E.; Grevy, S.; Stodel, C.; Thomas, J. C. [GANIL, Caen (France); Danchev, M. [University of Sofia (Bulgaria); Daugas, J. M. [CEA, DAM, DIF, 91297 Arpajon cedex (France); Hass, M.; Kumar, V. [The Weizmann Institute, Rehovot (Israel); Leske, J.; Pietralla, N. [TU Darmstadt, Darmstadt (Germany)

2009-08-26T23:59:59.000Z

333

Design features of high-intensity medium-energy superconducting heavy-ion Linac.  

DOE Green Energy (OSTI)

The proposed Rare Isotope Accelerator (RIA) requires the construction of a cw 1.4 GV superconducting (SC) linac that is capable of producing 400 kW beams of all ions from protons at 900 MeV to uranium at 400 MeV/u. The design of such a linac was outlined at the previous Linac conference. This linac will accelerate multiple-charge-states (multi-q) of the heaviest ion beams, for which the beam current is limited by ion-source performance. The linac consists of two different types of accelerating and focusing lattice: for uranium below {approx}85 MeV/u the focusing is provided by SC solenoids installed in cryostats with the SC resonators while in the high-beta section the focusing elements are located outside of the cryostats. A detailed design has been developed for the focusing-accelerating lattice of the linac. Beam dynamics studies have been performed with the goal of optimization of the linac structure in order to reduce a possible effective emittance growth of the multi-q uranium beam. A wide tuning range of the accelerating and focusing fields is required for acceleration of the variety of ions with different charge-to-mass ratios to the highest possible energy in single charge state mode. The focusing must be retuned for different ion masses to avoid resonance coupling between the transverse and longitudinal motions. Any visible impact of this coupling on the formation of beam halo must be avoided due to the high beam power.

Ostroumov, P. N.

2002-09-20T23:59:59.000Z

334

Transverse Energy Measurement and Fluctuation Studies in Ultra-Relativistic Heavy Ion Collisions  

E-Print Network (OSTI)

Transverse energy ($E_T$) has been measured with both of it's components, namely hadronic ($E_T^{had}$) and electromagnetic ($E_T^{em}$) at mid-rapidity, for 62.4 GeV Au+Au collisions by the STAR experiment. In the common phase space of TPC and BEMC ($0 tower hits after correcting for the hadronic contaminations in the calorimeter. The centrality behavior of $/(0.5 N_{part})$ and the excitation function of $/(0.5 N_{part})$ has been compared with the final state gluon saturation model (EKRT) along with similar measurements from SPS to RHIC. The most striking feature is the observation of a nearly constant value of $E_T/N_{ch} \\sim 0.8$ GeV from AGS, SPS to RHIC. The $E_T$ and $N_{ch}$ production has been observed to follow a logarithmic behavior. The initial energy density estimated by the boost-invariant Bjorken hydrodynamic model, is well above the lattice QCD value for a deconfined matter of Quarks and Gluons. Taking similar colliding species i.e. Au+Au, the $\\epsilon_{Bj} .\\tau$ has been predicted for LHC, based on the measurements at RHIC. We have also made predictions for $(dE_T/d\\eta)/(0.5 N_{part})$ and $(dN_{ch}/d\\eta)/(0.5 N_{part})$ for the LHC energy. Furthermore, we have studied the event-by event fluctuations in $E_T$ and in the ratio of it's components using $\\sigma/\\mu$ as the fluctuation observable.

Raghunath Sahoo

2008-04-10T23:59:59.000Z

335

Heavy ion fusion half-year report, October 1, 1979-March 31, 1980  

Science Conference Proceedings (OSTI)

Major elements of the program in the first half of Fiscal Year 1980 included: (1) characterization of the 1 amp, 1 MV, 2 ..mu..s beam after acceleration through one pulsed drift tube; (2) observation of current and energy spikes at the onset of the beam pulse occasioned by the unusually long transit-time (approx. 1 ..mu..sec) of the mass 133 ions across the diode gap; (3) completion of the full system, comprising of source and three drift-tubes, in February 1980; (4) development of new beam diagnostic probes for high-intensity ion beams; and (5) a major re-direction of the design effort on the Induction Linac Test Bed to bring costs, based on R/D funds that include overhead, down from the 40 million system (described in LBL PUB-5031) to the canonical 25 million.

Not Available

1980-03-01T23:59:59.000Z

336

muon Collider Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

Muon Collider Notes Muon Collider Notes MC-001 D. Neuffer, "Colliding Muon Beams at 90 GeV" Fermilab Note FN-319, July 1979. MC-002 D. Neuffer, "Principles and Applications of Muon Cooling" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 481, 1983. MC-003 V.V. Parkhomchuk and A.N. Skrinsky, "Ionization Cooling: Physics and Applications" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 485, 1983. MC-004 E.A. Perevedentsev and A.N. Skrinsky, "On the Proton Klystron" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 508, 1983. MC-005 D. Neuffer, "Principles and Applications of Muon Cooling" Particle Accelerators, Vol. 14, p. 75, 1983. MC-006 D. Neuffer, "Multi-TeV Muon Colliders" Proc. of the Advanced

337

Linear collider: a preview  

Science Conference Proceedings (OSTI)

Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center.

Wiedemann, H.

1981-11-01T23:59:59.000Z

338

PROCEEDINGS OF THE SECOND WORKSHOP ON EXPERIMENTS AND DETECTORS FOR A RELATIVISTIC HEAVY ION COLLIDER (RHIC), LAWRENCE BERKELEY LABORATORY, MAY 25-29, 1987  

E-Print Network (OSTI)

at RHIC. Designing the "event trigger" is important for thecollisions, the event trigger for "high multiplicity" or "can be used as an event trigger in their experiment. We have

Ritter, Hans Georg

2010-01-01T23:59:59.000Z

339

PROCEEDINGS OF THE SECOND WORKSHOP ON EXPERIMENTS AND DETECTORS FOR A RELATIVISTIC HEAVY ION COLLIDER (RHIC), LAWRENCE BERKELEY LABORATORY, MAY 25-29, 1987  

E-Print Network (OSTI)

BGO crystals or Pb-glass blocks could be used. to comparelayer calorimetry, BOO or v Pb-glass blocks for em showers

Ritter, Hans Georg

2010-01-01T23:59:59.000Z

340

The TESLA superconducting linear collider  

Science Conference Proceedings (OSTI)

This paper summarizes the present status of the studies for a superconducting Linear Collider (TESLA).

R. Brinkmann; the TESLA Collaboration

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Formation of Dense Partonic Matter in High Energy Heavy-Ion Collisions: Highlights of RHIC Results  

E-Print Network (OSTI)

I review some important results from RHIC experiments. They were obtained in a unique environment for studying QCD bulk matter at temperatures and densities that surpass the limits where hadrons can exist as individual entities, raising the quark-gluon degrees of freedom to prominence. These findings support the major experimental observations from measuring the bulk properties of particle production, particle ratios and chemical freeze-out conditions, elliptic flow followed by hard probes measurements: di-jet fragment azimuthal correlations, high-pt hadron suppression, and heavy-flavors probes. I present the measurements as a function of collision centrality, energy, system size and for different particle species. These results reveal that a dense strongly interacting medium was created in central Au+Au collisions at 200 GeV: the RHIC discovery. Further, they suggest that this medium is partonic. However, the discoveries so far observed at RHIC are far from being understood fully. Accordingly, the focus of the experiments has shifted from the discovery phase to the detailed exploration phase of the properties of this medium.

Rachid Nouicer

2009-01-07T23:59:59.000Z

342

Alternative Scenarios of Relativistic Heavy-Ion Collisions: II. Particle Production  

E-Print Network (OSTI)

Particle production in relativistic collisions of heavy nuclei is analyzed in a wide range of incident energies 2.7 GeV $\\le \\sqrt{s_{NN}}\\le$ 62.4 GeV. The analysis is performed within the three-fluid model employing three different equations of state (EoS): a purely hadronic EoS, an EoS with the first-order phase transition and that with a smooth crossover transition. It is found that the hadronic scenario fails to reproduce experimental yields of antibaryons (strange and nonstrange), starting already from lower SPS energies, i.e. $\\sqrt{s_{NN}}>$ 5 GeV. Moreover, at energies above the top SPS one, i.e. $\\sqrt{s_{NN}}>$ 17.4 GeV, the mid-rapidity densities predicted by the hadronic scenario considerably exceed the available RHIC data on all species. At the same time the deconfinement-transition scenarios reasonably agree (to a various extent) with all the data. The present analysis demonstrates certain advantage of the deconfinement-transition EoS's. However, all scenarios fail to reproduce the strangeness enhancement in the incident energy range near 30A GeV (i.e. a horn anomaly in the $K^+/\\pi^+$ ratio) and yields of $\\phi$-mesons at 20A--40A GeV.

Yu. B. Ivanov

2013-04-05T23:59:59.000Z

343

ATM-Dependent Hyper-Radiosensitivity in Mammalian Cells Irradiated by Heavy Ions  

SciTech Connect

Purpose: Low-dose hyper-radiosensitivity (HRS) and the later appearing radioresistance (termed induced radioresistance [IRR]) was mainly studied in low linear energy transfer (LET) radiation with survival observation. The aim of this study was to find out whether equivalent hypersensitivity occurred in high LET radiation, and the roles of ataxia telangiectasia mutated (ATM) kinase. Methods and Materials: Survival and mutation were measured by clonogenic assay and HPRT mutation assay. ATM Ser1981 activation was detected by Western blotting and immunofluorescent staining. Pretreatment of specific ATM inhibitor (10 {mu}M KU55933) and activator (20 {mu}g/mL chloroquine) before carbon radiation were adopted to explore the involvement of ATM. The roles of ATM were also investigated in its G2/M checkpoint function with histone H3 phosphorylation analysis and flow cytometric assay, and DNA double strand break (DSB) repair function measured using {gamma}-H2AX foci assay. Results: HRS/IRR was observed with survival and mutation in normal human skin fibroblast cells by carbon ions, while impaired in cells with intrinsic ATM deficiency or normal cells modified with specific ATM activator or inhibitor before irradiation. The dose-response pattern of ATM kinase activation was concordant with the transition from HRS to IRR. The ATM-dependent 'early' G2 checkpoint arrest and DNA DSB repair efficiency could explain the difference between HRS and IRR. Conclusions: These data demonstrate that the HRS/IRR by carbon ion radiation is an ATM-dependent phenomenon in the cellular response to DNA damage.

Xue Lian [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China); Yu Dong [Tumor Endocrinology Project, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)], E-mail: ydong@ncc.go.jp; Furusawa, Yoshiya [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba-shi (Japan); Cao Jianping [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China); Okayasu, Ryuichi [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba-shi (Japan); Fan Saijun [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China)

2009-09-01T23:59:59.000Z

344

Tau tau Fusion to SUSY Higgs Bosons at a Photon Collider: Measuring tan(beta)  

E-Print Network (OSTI)

Tau tau fusion to light h and heavy H,A Higgs bosons is investigated in the Minimal Supersymmetric Standard Model (MSSM) at a photon collider as a promising channel for measuring large values of tan(beta). For standard design parameters of a photon collider an error close to unity, uniform for tan(beta) above 10, may be expected, improving on complementary measurements at LHC and e+e- linear colliders.

S. Y. Choi; J. Kalinowski; J. S. Lee; M. M. Muehlleitner; M. Spira; P. M. Zerwas

2004-07-05T23:59:59.000Z

345

Photon collider at TESLA  

E-Print Network (OSTI)

High energy photon colliders (gamma-gamma, gamma-electron) based on backward Compton scattering of laser light is a very natural addition to e+e- linear colliders. In this report we consider this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case the gamma-gamma luminosity luminosity in the high energy part of spectrum can reach (1/3)L_{e+e-}. Typical cross sections of interesting processes in gamma-gamma collisions are higher than those in e+e- collisions by about one order of magnitude, so the number of events in gamma-gamma collisions will be more than that in e+e- collisions. Photon colliders can, certainly, give additional information and they are the best for the study of many phenomena. The main question is now the technical feasibility. The key new element in photon colliders is a very powerful laser system. An external optical cavity is a promising approach for the TESLA project. A free electron laser is another option. However, a more straightforward solution is ``an optical storage ring (optical trap)'' with diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters and existing problems.

Valery Telnov

2000-10-13T23:59:59.000Z

346

Time delays in heavy-ion-induced fission of medium-Z nuclei, measured by crystal blocking  

Science Conference Proceedings (OSTI)

Time delays in fission induced by bombardment of Mo with 170- and 180-MeV {sup 32}S, 225- and 240-MeV {sup 48}Ti, and 300-MeV {sup 58}Ni have been measured by observation of crystal blocking of fission fragments. In contrast to earlier measurements with a W target, the results are consistent with fission of a compound nucleus in competition with mainly neutron emission. Most of the fissions happen on a time scale much shorter than attoseconds but there is a significant component of fission with much longer lifetimes. The measurements are reproduced with a standard statistical model, including a Kramers correction to fission widths from the viscosity of hot nuclear matter. These new results support the interpretation of our earlier measurements with a W target, which indicate that there is a transition in heavy-ion-induced fission at large atomic number and mass, from multichance fission in the standard Bohr-Wheeler picture to fission without formation of a compound nucleus. The process is slowed down by nuclear viscosity, with measured delays of order attoseconds.

Andersen, J. U. [Aarhus University; Chevallier, J. [University of Aarhus, Denmark; Forster, J. S. [Universite de Montreal; Karamian, S. A. [FLNR-JINR, Russia; Vane, C Randy [ORNL; Beene, James R [ORNL; Gross, Carl J [ORNL; Krause, Herbert F [ORNL; Liang, J Felix [ORNL; Shapira, Dan [ORNL; Uguzzoni, A. [University of Bologna

2012-01-01T23:59:59.000Z

347

Analysis of the baryon-, proton-, and charged particle kurtosis in heavy ion collisions within a relativistic transport approach  

E-Print Network (OSTI)

We explore the potential of recent lattice QCD predictions on net baryon number, net charge and net proton fluctuations (in terms of an effective kurtosis) to investigate the properties of hot and dense matter created in relativistic heavy ion reactions. Lattice QCD suggests a value for the baryon number fluctuation between 0 and 1, depending whether the system is in the hadron gas phase or in the quark gluon phase. The present analysis is performed on simulated events taking into account realistic fluctuations due to stopping, resonance decays, etc. while conserving electric and baryon charge exactly on an event-by-event basis. The investigations are performed within the UrQMD framework for Pb+Pb reactions in the energy range from E_lab = 20A to 158A GeV. We find that the effective kurtosis of net proton fluctuations (being experimentally more feasible than net baryon fluctuations) around midrapidity are compatible with 0 +/- 1. However, the baryon number effective kurtosis is found to be negative in the who...

Schuster, Tim; Mitrovski, Michael; Stock, Reinhard; Bleicher, Marcus

2009-01-01T23:59:59.000Z

348

Head shock vs Mach cone: azimuthal correlations from 2 to 3 parton processes in relativistic heavy-ion collisions  

E-Print Network (OSTI)

We study the energy-momentum deposited by fast moving partons within a medium using linearized viscous hydrodynamics. The particle distribution produced by this energy-momentum is computed using the Cooper-Frye formalism. We show that for the conditions arising in heavy-ion collisions, energy momentum is preferentially deposited along the head shock of the fast moving partons. We also show that the double hump in the away-side of azimuthal correlations can be produced by two (instead of one) away-side partons that deposit their energy-momentum along their directions of motion. These partons are originated in the in-medium hard scattering in 2 to 3 processes. We compare the results of the analysis to azimuthal angular correlations from PHENIX and show that the calculation reproduces the data systematics of a decreasing away-side correlation when the momentum of the associated hadron becomes closer to the momentum of the leading hadron. This scenario seems to avoid the shortcomings of the Mach cone as the origin of the double-hump structure in the away-side

Alejandro Ayala; Isabel Dominguez; Maria Elena Tejeda-Yeomans

2012-12-05T23:59:59.000Z

349

Mass-energy distribution of fragments within Langevin dynamics of fission induced by heavy ions  

SciTech Connect

A stochastic approach based on four-dimensional Langevin fission dynamics is applied to calculating mass-energy distributions of fragments originating from the fission of excited compound nuclei. In the model under investigation, the coordinate K representing the projection of the total angular momentum onto the symmetry axis of the nucleus is taken into account in addition to three collective shape coordinates introduced on the basis of the {l_brace}c, h, {alpha}{r_brace} parametrization. The evolution of the orientation degree of freedom (K mode) is described by means of the Langevin equation in the overdamped regime. The tensor of friction is calculated under the assumption of the reducedmechanismof one-body dissipation in the wall-plus-window model. The calculations are performed for two values of the coefficient that takes into account the reduction of the contribution from the wall formula: k{sub s} 0.25 and k{sub s} = 1.0. Calculations with a modified wall-plus-window formula are also performed, and the quantity measuring the degree to which the single-particle motion of nucleons within the nuclear system being considered is chaotic is used for k{sub s} in this calculation. Fusion-fission reactions leading to the production of compound nuclei are considered for values of the parameter Z{sup 2}/A in the range between 21 and 44. So wide a range is chosen in order to perform a comparative analysis not only for heavy but also for light compound nuclei in the vicinity of the Businaro-Gallone point. For all of the reactions considered in the present study, the calculations performed within four-dimensional Langevin dynamics faithfully reproduce mass-energy and mass distributions obtained experimentally. The inclusion of the K mode in the Langevin equation leads to an increase in the variances of mass and energy distributions in relation to what one obtains from three-dimensional Langevin calculations. The results of the calculations where one associates k{sub s} with the measure of chaoticity in the single-particle motion of nucleons within the nuclear system under study are in good agreement for variances of mass distributions. The results of calculations for the correlations between the prescission neutron multiplicity and the fission-fragment mass, Left-Pointing-Angle-Bracket n{sub pre}(M) Right-Pointing-Angle-Bracket , and between, this multiplicity and the kinetic energy of fission fragments, Left-Pointing-Angle-Bracket n{sub pre}(E{sub k}) Right-Pointing-Angle-Bracket , are also presented.

Anischenko, Yu. A., E-mail: yuri.anischenko@gmail.com; Adeev, G. D. [Omsk State University (Russian Federation)

2012-08-15T23:59:59.000Z

350

Effects of nuclear symmetry energy on eta meson production and its rare decay to the dark U-boson in heavy-ion reactions  

E-Print Network (OSTI)

Using a relativistic transport model ART1.0, we explore effects of nuclear symmetry energy on eta meson production and its rare decay to the dark U-boson in heavy-ion reactions from 0.2 to 10 GeV/nucleon available at several current and future facilities. The yield of eta mesons at sub-threshold energies is found to be very sensitive to the density dependence of nuclear symmetry energy. Above a beam energy of about 5 GeV/nucleon in Au+Au reactions, the sensitivity to symmetry energy disappears. Using the branching ratio of the rare eta decay (eta->gamma U) available in the literature, we estimate the maximum cross section for the U-boson production in the energy range considered, providing a useful reference for future U-boson search using heavy-ion reactions.

Gao-Chan Yong; Bao-An Li

2013-03-05T23:59:59.000Z

351

Nuclear interactions in high energy heavy ions and applications in astrophysics. Technical progress report, 1 April 1992--31 March 1993  

SciTech Connect

The overall objective is to study the mechanisms and the energy dependence of heavy ion fragmentation by studying the reactions of heavy ion projectiles (e.g. {sup 4}He, {sup 16}O, {sup 20}Ne, {sup 28}Si, {sup 56}Fe) in a variety of targets (H, He, C, Si, Cu, Pb) and at a number of beam energies exceeding 0.1 GeV/nucleon. The results have application to questions in high-energy nuclear astrophysics. Most of the discussion is on low-energy {sup 16}O,{sup 28}Si data analysis. The description includes analysis procedures and techniques, detector calibrations, data selections and normalizations. Cross section results for the analysis are also presented. 83 figs., 6 tabs., 73 refs.

Wefel, J.P.; Guzik, T.G.

1993-01-11T23:59:59.000Z

352

Nuclear interactions in high energy heavy ions and applications in astrophysics. [Dept. of Physics and Astronomy, Louisiana State Univ. , Baton Rouge  

SciTech Connect

The overall objective is to study the mechanisms and the energy dependence of heavy ion fragmentation by studying the reactions of heavy ion projectiles (e.g. [sup 4]He, [sup 16]O, [sup 20]Ne, [sup 28]Si, [sup 56]Fe) in a variety of targets (H, He, C, Si, Cu, Pb) and at a number of beam energies exceeding 0.1 GeV/nucleon. The results have application to questions in high-energy nuclear astrophysics. Most of the discussion is on low-energy [sup 16]O,[sup 28]Si data analysis. The description includes analysis procedures and techniques, detector calibrations, data selections and normalizations. Cross section results for the analysis are also presented. 83 figs., 6 tabs., 73 refs.

Wefel, J.P.; Guzik, T.G.

1993-01-11T23:59:59.000Z

353

Effects of nuclear symmetry energy on eta meson production and its rare decay to the dark U-boson in heavy-ion reactions  

E-Print Network (OSTI)

Using a relativistic transport model ART1.0, we explore effects of nuclear symmetry energy on eta meson production and its rare decay to the dark U-boson in heavy-ion reactions from 0.2 to 10 GeV/nucleon available at several current and future facilities. The yield of eta mesons at sub-threshold energies is found to be very sensitive to the density dependence of nuclear symmetry energy. Above a beam energy of about 5 GeV/nucleon in Au+Au reactions, the sensitivity to symmetry energy disappears. Using the branching ratio of the rare eta decay (eta->gamma+U) available in the literature, we estimate the maximum cross section for the U-boson production in the energy range considered, providing a useful reference for future U-boson search using heavy-ion reactions.

Yong, Gao-Chan

2013-01-01T23:59:59.000Z

354

Compositional analysis and depth profiling of thin film CrO{sub 2} by heavy ion ERDA and standard RBS: a comparison  

Science Conference Proceedings (OSTI)

Chromium dioxide (CrO{sub 2}) thin film has generated considerable interest in applied research due to the wide variety of its technological applications. It has been extensively investigated in recent years, attracting the attention of researchers working on spintronic heterostructures and in the magnetic recording industry. However, its synthesis is usually a difficult task due to its metastable nature and various synthesis techniques are being investigated. In this work a polycrystalline thin film of CrO{sub 2} was prepared by electron beam vaporization of Cr{sub 2}O{sub 3} onto a Si substrate. The polycrystalline structure was confirmed through XRD analysis. The stoichiometry and elemental depth distribution of the deposited film were measured by ion beam nuclear analytical techniques heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS), which both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. Moreover, the analysis carried out highlights the importance of complementary usage of the two techniques to obtain a more complete description of elemental content and depth distribution in thin films. - Graphical abstract: Heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS) both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. Highlights: Black-Right-Pointing-Pointer Thin films of CrO{sub 2} have been grown by e-beam evaporation of Cr{sub 2}O{sub 3} target in vacuum. Black-Right-Pointing-Pointer The composition was determined by heavy ion-ERDA and RBS. Black-Right-Pointing-Pointer HI-ERDA and RBS provided information on the light and heavy elements, respectively.

Khamlich, S., E-mail: skhamlich@gmail.com [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); The African Laser Centre, CSIR campus, P.O. Box 395, Pretoria (South Africa); Msimanga, M., E-mail: mandla@tlabs.ac.za [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); iThemba LABS Gauteng, Private Bag 11, WITS 2050, Johannesburg (South Africa); Pineda-Vargas, C.A. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Faculty of Health and Wellness Sciences, C.P.U.T., P.O. Box 1906, Bellville 7535 (South Africa); Nuru, Z.Y. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); McCrindle, R. [Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); Maaza, M. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); The African Laser Centre, CSIR campus, P.O. Box 395, Pretoria (South Africa)

2012-08-15T23:59:59.000Z

355

A spectroscopic ellispometric study of the tunability of the optical constants and thickness of GeO{sub x} films with swift heavy ions  

Science Conference Proceedings (OSTI)

Sub-stoichiometric GeO{sub x} films were fabricated by electron-beam evaporation method. The films were irradiated with 100 MeV Ag{sup 7+} ions at fluences between 1 x 10{sup 12} and 1 x 10{sup 14} ions-cm{sup -2}. Spectroscopic ellipsometric measurements were performed in air at room temperature. The values of the layer thickness and refractive index were extracted from ellipsometry using a multilayer analysis and the Tauc Lorentz model. The refractive index (at 633 nm) of the as-deposited GeO{sub x} film was estimated to be 1.860 and decreased to 1.823 for films irradiated at an ion fluence of 1 x 10{sup 14} ions-cm{sup -2}. The thickness of the films also decreased after irradiation and is due to a sputtering induced by the ion beam. The change in the refractive index with ion fluence is attributed to a stoichiometric change and structural transformation represented by GeO{sub x}{yields} Ge + GeO{sub y} (y > x) occurring due to a thermal spike induced by ion irradiation. Swift heavy ions thus provide a scope for modulating the refractive index of GeO{sub x} films. The thickness and stoichiometric changes are supported by Rutherford backscattering measurements.

Vijayarangamuthu, K.; Singh, Chaman; Rath, Shyama [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Kabiraj, D. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

2011-09-15T23:59:59.000Z

356

Dark matter at colliders  

SciTech Connect

We show that colliders can impose strong constraints on dark matter. We take an effective field theory approach where dark matter couples to quarks and gluons through high dimensional operators. We discuss limits on interactions of dark matter and hadronic matter from the ATLAS experiment at the Large Hadron Collider (LHC). For spin-independent scattering, the LHC limits are stronger than those from direct detection experiments for light WIMPs. For spin-dependent scattering, the LHC sets better limits over much of parameter space.

Yu Haibo [Department of Physics, University of Michigan, Ann Arbor, MI, 48109 (United States)

2013-05-23T23:59:59.000Z

357

CHEMICAL PROCESSING OF PURE AMMONIA AND AMMONIA-WATER ICES INDUCED BY HEAVY IONS  

SciTech Connect

Cosmic rays are possibly the main agents to prevent the freeze-out of molecules onto grain surfaces in cold dense clouds. Ammonia (NH{sub 3}) is one of the most abundant molecules present in dust ice mantles, with a concentration of up to 15% relative to water (H{sub 2}O). FTIR spectroscopy is used to monitor pure NH{sub 3} and NH{sub 3}-H{sub 2}O ice samples as they are irradiated with Ni and Zn ion beams (500-600 MeV) at GANIL/France. New species, such as hydrazine (N{sub 2}H{sub 4}), diazene (N{sub 2}H{sub 2} isomers), molecular hydrogen (H{sub 2}), and nitrogen (N{sub 2}) were identified after irradiation of pure NH{sub 3} ices. Nitrous oxide (N{sub 2}O), nitrogen oxide (NO), nitrogen dioxide (NO{sub 2}), and hydroxylamine (NH{sub 2}OH) are some of the products of the NH{sub 3}-H{sub 2}O ice radiolysis. The spectral band at 6.85 {mu}m was observed after irradiation of both types of ice. Besides the likely contribution of ammonium (NH{sub 4}{sup +}) and amino (NH{sub 2}) radicals, data suggest a small contribution of NH{sub 2}OH to this band profile after high fluences of irradiation of NH{sub 3}-H{sub 2}O ices. The spectral shift of the NH{sub 3} ''umbrella'' mode (9.3 {mu}m) band is parameterized as a function of NH{sub 3}/H{sub 2}O ratio in amorphous ices. Ammonia and water destruction cross-sections are obtained, as well as the rate of NH{sub 3}-H{sub 2}O (1:10) ice compaction, measured by the OH dangling bond destruction cross-section. Ammonia destruction is enhanced in the presence of H{sub 2}O in the ice and a power law relationship between stopping power and NH{sub 3} destruction cross-section is verified. Such results may provide relevant information for the evolution of molecular species in dense molecular clouds.

Bordalo, V.; Da Silveira, E. F. [Departamento de Fisica/Laboratorio do Acelerador Van de Graaff, Pontificia Universidade Catolica do Rio de Janeiro, Rua Marques de S. Vicente 225, 22451-900 Rio de Janeiro, RJ (Brazil); Lv, X. Y.; Domaracka, A.; Rothard, H.; Boduch, P. [Centre de Recherche sur les Ions, les Materiaux et la Photonique (CEA/CNRS/ENSICAEN/Universite de Caen-Basse Normandie), CIMAP-CIRIL-GANIL, Boulevard Henri Becquerel, BP 5133, F-14070 Caen Cedex 05 (France); Seperuelo Duarte, E., E-mail: vbordalo@fis.puc-rio.br [Grupo de Fisica e Astronomia, Instituto Federal do Rio de Janeiro, Rua Lucio Tavares 1045, 26530-060 Nilopolis, RJ (Brazil)

2013-09-10T23:59:59.000Z

358

Experimental Cross Sections for Reactions of Heavy Ions and 208Pb, 209Bi, 238U, and 248Cm Targets  

Science Conference Proceedings (OSTI)

The study of the reactions between heavy ions and {sup 208}Pb, {sup 209}Bi, {sup 238}U, and {sup 248} Cm targets was performed to look at the differences between the cross sections of hot and cold fusion reactions. Experimental cross sections were compared with predictions from statistical computer codes to evaluate the effectiveness of the computer code in predicting production cross sections. Hot fusion reactions were studied with the MG system, catcher foil techniques and the Berkeley Gas-filled Separator (BGS). 3n- and 4n-exit channel production cross sections were obtained for the {sup 238}U({sup 18}O,xn){sup 256-x}Fm, {sup 238}U({sup 22}Ne,xn){sup 260-x}No, and {sup 248}Cm({sup 15}N,xn){sup 263-x}Lr reactions and are similar to previous experimental results. The experimental cross sections were accurately modeled by the predictions of the HIVAP code using the Reisdorf and Schaedel parameters and are consistent with the existing systematics of 4n exit channel reaction products. Cold fusion reactions were examined using the BGS. The {sup 208}Pb({sup 48}Ca,xn){sup 256-x}No, {sup 208}Pb({sup 50}Ti,xn){sup 258-x}Rf, {sup 208}Pb({sup 51}V,xn){sup 259-x}Db, {sup 209}Bi({sup 50}Ti,xn){sup 259-x}Db, and {sup 209}Bi({sup 51}V,xn){sup 260-x}Sg reactions were studied. The experimental production cross sections are in agreement with the results observed in previous experiments. It was necessary to slightly alter the Reisdorf and Schaedel parameters for use in the HIVAP code in order to more accurately model the experimental data. The cold fusion experimental results are in agreement with current 1n- and 2n-exit channel systematics.

Patin, Joshua B.

2002-05-24T23:59:59.000Z

359

Studies of complex fragment emission in heavy ion reactions. Progress report, January 1, 1990--August 5, 1992  

Science Conference Proceedings (OSTI)

Our work involves the study of intermediate energy heavy-ion nuclear reactions. This work has two foci. On the one hand, we desire to learn about the properties of nuclear matter under abnormal conditions, in this energy domain, predominately low densities. This purpose runs abreast of the second, which is the study of the relevant reaction mechanisms. The two objectives are inexorably linked because our experimental laboratory for studying nuclear matter properties is a dynamic one. We are forced to ask how nuclear matter properties, such as phase transitions, are reflected in the dynamics of the reactions. It may be that irrefutable information about nuclear matter will not be extracted from the reaction work. Nevertheless, we are compelled to undertake this effort not only because it is the only game in town and as yet we do not know that information cannot be extracted, but also because of our second objective. The process leads to an understanding of the reaction mechanism themselves and therefore to the response characteristics of finite, perhaps non-equilibrium, strongly interacting systems. Our program has been: To study energy, mass, and angular momentum deposition by studying incomplete fusion reactions. To gain confidence that we understand how highly excited systems decompose by studying all emissions from the highly excited systems. To push these kinds of studies into the intermediate energy domain, with excitation function studies. And attempt to learn about the dynamics of the decays using particle-particle correlations. In the last effort, we have decided to focus on simple systems, where we believe, definitive statements are possible. These avenues of research share a common theme, large complex fragment production.

Charity, R.J.; Sobotka, L.G.

1992-09-01T23:59:59.000Z

360

High intensity production of high and medium charge state uranium and other heavy ion beams with VENUS  

E-Print Network (OSTI)

is the first third generation source routinely operated atIntroduction Third generation ECR ion sources are designedfor 4 th generation ECR ion sources [9] . The VENUS

Leitner, Daniela; Galloway, Michelle L.; Loew, Timothy J.; Lyneis, Claude M.; Rodriguez, Ingrid Castro; Todd, Damon S.

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


361

Nuclear modification factor of nonphotonic electrons in heavy-ion collisions, and the heavy-flavor baryon-to-meson ratio  

E-Print Network (OSTI)

The nuclear modification factor R(AA) of nonphotonic electrons in Au + Au collisions at root(S)NN = 200 GeV is studied by considering the decays of heavy-flavor hadrons produced in a quark coalescence model. Although an enhanced Lambda(c)/D(0) ratio is predicted by the coalescence model, it is peaked at small transverse momenta (similar to 2 GeV) due to the large difference between heavy and light quark masses. As a result, the enhanced Lambda(c)/D(0) ratio, which is expected to suppress the electron R(AA) as the branching ratio of Lambda(c) decay into electrons is smaller than that of D(0), does not lead to additional suppression of the electron R(AA) at large transverse momenta (>= 5 GeV), where the suppression is mainly due to heavy quark energy loss in produced quark-gluon plasma. Also, the enhanced Lambda(b)/(B) over bar (0) ratio predicted by the coalescence model has even smaller effect on the nonphotonic electron R(AA) as bottom baryons and mesons have similar branching ratios for semileptonic decays into electrons.

Oh, Yongseok; Ko, Che Ming.

2009-01-01T23:59:59.000Z

362

Is it possible to create a quantum electromagnetic "black hole" at the Large Hadron Collider?  

E-Print Network (OSTI)

As demonstrated by Chernodub, strong magnetic field forces vacuum to develop real condensates of electrically charged rho mesons, which form an anisotropic inhomogeneous superconducting state similar to Abrikosov vortex lattice. As far as electromagnetic field behaviour is concerned, this state of vacuum constitutes a hyperbolic metamaterial [1]. Here we demonstrate that spatial variations of magnetic field may lead to formation of electromagnetic "black holes" inside this metamaterial. Similar to real black holes, horizon area of the electromagnetic "black holes" is quantized in units of the effective "Planck scale" squared. The magnetic fields of the required strength and geometrical configuration may be created on Earth in heavy-ion collisions at the Large Hadron Collider. We evaluate electromagnetic field distribution around an electromagnetic "black hole" which may be created as a result of such collision.

Igor I. Smolyaninov

2012-04-04T23:59:59.000Z

363

Muon Collider Progress: Accelerators  

SciTech Connect

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 10{sup 34} cm{sup 2}s{sup 1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (cooling). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

Zisman, Michael S.

2011-09-10T23:59:59.000Z

364

muon_collider  

NLE Websites -- All DOE Office Websites (Extended Search)

muon_collider muon_collider muon_collider FridayMeetings MCTFmeetings MondayMeetings prstab texput.log #prstab.tex# last.kumac prstab.ps arxiv.tar.gz prstab.tar.gz referee_response_II.pdf prstab.pdf prstab.aux prstab.dvi prstab.end prstab.log prstab.tex prstab.tex~ accel-010307-f03.eps accel-010307-f28.eps old conclusions.tex higgsfact.tex introduction.tex mice.tex neufact.tex physics.tex prstab.tex r_and_d.tex authors_merged.tex buncher.tex temp.prt last.kumacold ringfig.eps MICE-fig.ps chgr_norm.ps chgr_merit.ps temp.csh temp.prt~ xupdn-a-model-view-iron5.eps site1-Layout1.eps rla2.eps phaserot.eps mole-hill.eps intoap.eps emit.eps cavity.eps allcount.eps MICE-88MHz-cooling.eps changes hh_ha_susy_rtsscan.eps letter_plots.eps scott33.eps scott32b.eps scott32a.eps MICE-200MHz-long.eps MICE-resolution.eps dipole_fields.eps

365

ULTRARELATIVISTIC HEAVY IONS  

E-Print Network (OSTI)

energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and

Pugh, H.G.

2010-01-01T23:59:59.000Z

366

HEAVY-ION DOSIMETRY  

E-Print Network (OSTI)

10. These consist of a brass plate with a precisely maclrnedridge f i l t e r , an additional 4-rnn brass p l a t e , ac e r t r a l brass cylinder, and a concentric brass r i n

Schimmerling, W.

2010-01-01T23:59:59.000Z

367

HEAVY ION INERTIAL FUSION  

E-Print Network (OSTI)

in the Tokamak Fusion Test Reactor which will be completedDrivers and Reactors for Inertial Confinement Fusion, K.A.

Keefe, D.

2008-01-01T23:59:59.000Z

368

RELATIVISTIC HEAVY ION EXPERIMENTS  

E-Print Network (OSTI)

ve for the study of very high energy nucleus-nucleus collisions is to observe the properties of nuclear

Pugh, H.G.

2010-01-01T23:59:59.000Z

369

Relativistic heavy ions physics  

SciTech Connect

Central nuclear collisions at energies far above 1 GeV/nucleon may provide for conditions, where the transition from highly excited hadronic matter into quark matter or quark-gluon plasma can be probed. We review current ideas about the nature of, and signals for, this transition, and we discuss the (hadronic) string model approach to the nuclear collisions dynamics. At even higher energies in the TeV/nucleon range peripheral nuclear collisions may become a laboratory for electroweak physics at the unification scale allowing, e.g., for Higgs boson production. 42 refs., 29 figs.,

Mueller, B.

1989-01-01T23:59:59.000Z

370

Hanbury Brown-Ttiss Correlation Functions from Event Generators: A Reliable Approach to Determine the Size of the Emitting Source in Ultrarelativistic Heavy Ion Collisions?  

E-Print Network (OSTI)

Employing NEXUS, one of the most recent simulation programs for heavy ions collisions, we investigate in detail the Hanbury-Twiss correlation function for charged pions for reactions 158 GeV Pb+Pb. For this study we supplement the standard simulation program by electromagnetic interactions. We find that the string fragmentation introduces strong space-momentum correlations and the freeze out times of the correlated pairs have a wide distribution. Both has a strong influence on the apparent source radius determined from the measured correlation correlation function.An equally strong influence is observed for the final state electromagnetic interaction.

F. Gastineau; J. Aichelin

2000-07-20T23:59:59.000Z

371

Ion Sources, Preinjectors and the Road to EBIS (459th Brookhaven Lecture)  

Science Conference Proceedings (OSTI)

To meet the requirements of the scientific programs of the Relativistic Heavy Ion Collider and the NASA Space Radiation Lab, BNL's Collider-Accelerator Department needs a variety of ion sources. Although these sources are a relatively small and inexpensive part of an accelerator, they can have a big impact on the machine's overall performance. For the 459th Brookhaven Lecture, James Alessi will describe C-AD's long history of developing state-of-the-art ion sources for its accelerators, and its current process for source and pre-injector development. He will follow up with a discussion of the features and development status of EBIS, which, as the newest source and preinjector, is in the final stages of commissioning at the end of a five-year construction project.

Alessi, James (BNL Collider-Accelerator Dept)

2010-07-21T23:59:59.000Z

372

Results from hadron colliders  

SciTech Connect

The present status of hadron collider physics is reviewed. The total cross section for {bar p} + p has been measured at 1.8 TeV: {sigma}{sub tot} = 72.1 {plus minus} 3.3 mb. New data confirm the UA2 observation of W/Z {yields} {bar q}q. Precision measurements of M{sub W} by UA2 and CDF give an average value M{sub W} = 80.13 {plus minus} 0.30 GeV/c{sup 2}. When combined with measurements of M{sub Z} from LEP and SLC this number gives sin{sup 2}{theta}{sub W} = 0.227 {plus minus} 0.006, or m{sub top} = 130{sub {minus}60}{sup +40} GeV/c{sup 2} from the EWK radiative correction term {Delta}r. Evidence for hadron colliders as practical sources of b quarks has been strengthened, while searches for t quarks have pushed the mass above M{sub W}: m{sub top} > 89 GeV/c{sup 2} 95% cl (CDF Preliminary). Searches beyond the standard model based on the missing E{sub T} signature have not yet produced any positive results. Future prospects for the discovery of the top quark in the range m{sub top} < 200 GeV/c{sup 2} look promising. 80 refs., 35 figs., 7 tabs.

Pondrom, L.G. (Wisconsin Univ., Madison, WI (USA))

1990-12-14T23:59:59.000Z

373

Electron Ion Collider: The Next QCD Frontier  

E-Print Network (OSTI)

dominated region of the nucleon at the upgraded 12 GeV CEBAF at JLab and COMPASS at CERN. Applying these new orbital motion are expected to contribute. The 12 GeV upgrade of CEBAF at JLab will start on such studies upgraded CEBAF, now under construction, to achieve similar collision parameters. 10 #12;eSTAR ePHENIX 30GeV

Homes, Christopher C.

374

Photon collider at TESLA 1  

E-Print Network (OSTI)

High energy photon colliders (??, ?e) based on backward Compton scattering of laser light is a very natural addition to e + e ? linear colliders. In this report we consider this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case the ?? luminosity in the high energy part of spectrum can reach about (1/3)L e e ?. Typical cross sections of interesting processes in ?? collisions are higher than those in e + e ? collisions by about one order of magnitude, so the number of events in ?? collisions will be more than that in e + e ? collisions. Photon colliders can, certainly, give additional information and they are the best for the study of many phenomena. The main question is now the technical feasibility. The key new element in photon colliders is a very powerful laser system. An external optical cavity is a promising approach for the TESLA project. A free electron laser is another option. However, a more straightforward solution is an optical storage ring (optical trap) with a diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based on the linear collider TESLA, its possible parameters and existing problems. PACS: 29.17.+w, 41.75.Ht, 41.75.Lx, 13.60.Fz Key words: photon collider; linear collider; photon photon; gamma gamma; photon electron; Compton scattering; backscattering 1

Valery Telnov

2001-01-01T23:59:59.000Z

375

Colliding Crystalline Beams  

SciTech Connect

Crystalline Beams* are an ordered state of an ensemble of ions, circulating in a storage ring, with very small velocity fluctuations. They can be obtained from ordinary warm ion beams with the application of powerful cooling techniques (stochastic, electron, laser, ...). Depending on the focussing properties and dimensions of the storage ring, and on the ion beam density, several ground states are possible. All of them can be visualized as a bundle of n{sub s} symmetrically distributed, parallel strings. The longitudinal ion separation {lambda} is the same for all strings. The minimum temperature that can be achieved depends on die background noise of the cooling technique used. It is required for stability that the vibration amplitude of the ions is only a fraction of the separation {lambda}.

Haffmans, A.F.; Maletic, D.; Ruggiero, A.G.

1995-06-01T23:59:59.000Z

376

Probing the direct step of relativistic heavy ion fragmentation: (/sup 12/C, /sup 11/B+p) at 2. 1 GeV/nucleon with C and CH/sub 2/ targets  

DOE Green Energy (OSTI)

Relativistic heavy ion collisions may be classified as central (and near central), peripheral, and grazing with each collision type producing different proton and other charged projectile fragment scattering mechanisms and characteristics. This report focuses on peripheral and grazing collisions in the fragmentation of Carbon-12 into Boron-11 and a proton, testing models of the kinetics involved in this reaction. The data were measured at the Heavy Ion Superconducting Spectrometer (HISS) at Lawrence Berkeley Laboratory and include excitation energy for the p/Boron-11 pair, and rapidity versus transverse momentum for protons and Boron-11. 58 refs., 35 figs., 8 tabs. (DWL)

Webb, M.L.

1987-06-01T23:59:59.000Z

377

DEVELOPMENTS IN HEAVY QUARKONIUM SPECTROSCOPY  

E-Print Network (OSTI)

­ 1­ DEVELOPMENTS IN HEAVY QUARKONIUM SPECTROSCOPY Written May 2012 by S. Eidelman (Budker Inst. Navas (Univ. Granada), and C. Patrignani (Univ. Genova, INFN). A golden age for heavy quarkonium physics at HERA and the Tevatron matured; and heavy-ion collisions at RHIC opened a window on the deconfinement

378

Exclusive diffractive processes in electron-ion collisions  

E-Print Network (OSTI)

We present a new technique to calculate the cross-section for diffractive vector meson production and DVCS in electron-ion collisions based on the dipole model. The measurement of these processes can provide valuable information on non-linear QCD phenomena, such as gluon saturation, and is the the only known way to gain insight into the spatial distribution of gluons in nuclei. We present predictions of differential cross-section distribution $d\\sigma/dQ^2$ and $d\\sigma/dt$ for $J/\\psi$ and $\\phi$ meson production for diffractive processes of heavy nuclei and demonstrate the feasibility of extracting the gluon source distribution of heavy nuclei, F(b), from coherent diffraction. We briefly introduce a new event generator based on our method that can be used for studying exclusive diffractive processes at a future electron-ion collider.

Tobias Toll; Thomas Ullrich

2012-11-13T23:59:59.000Z

379

Links to Muon Collider Related Web Pages  

NLE Websites -- All DOE Office Websites (Extended Search)

Muon Collider related web pages: Muon Collider Feasibility Study ... Fermilab Page MUCOOL Collaboration: Ionization Cooling R&D Snowmass 1996 Feasibility Study Book Brookhaven Muon...

380

Director's colloquium March 18 large hadron collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Director's colloquium large hadron collider Director's colloquium March 18 large hadron collider Lyndon Evans of CERN will talk about the most complex scientific instrument ever...

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Neutrino Physics at a Muon Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics at a Muon Collider The intense muon beams needed for high luminosity muon colliders produce intense beams of neutrinos. Dedicated muon storage rings with long straight...

382

ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.  

SciTech Connect

This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linac. The highly successful development of an EBIS at BNL now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based pre-injectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; ET AL.

2005-02-28T23:59:59.000Z

383

Single phase formation of Co-implanted ZnO thin films by swift heavy ion irradiation: Optical studies  

SciTech Connect

Low temperature photoluminescence and optical absorption studies on 200 MeV Ag{sup +15} ion irradiated Co-implanted ZnO thin films were studied. The Co clusters present in as implanted samples were observed to be dissolved using 200 MeV Ag{sup +15} ion irradiation with a fluence of 1x10{sup 12} ions/cm{sup 2}. The photoluminescence spectrum of pure ZnO thin film was characterized by the I{sub 4} peak due to the neutral donor bound excitons and the broad green emission. The Co-doped ZnO films show three sharp levels and two shoulders corresponding to 3t{sub 2g} and 2e{sub g} levels of crystal field splitted Co d orbitals, respectively. The ultraviolet-visible absorption spectroscopy also shows the systematic variation of band gap after 200 MeV Ag{sup +15} ion irradiation.

Kumar, Ravi; Singh, Fouran; Angadi, Basavaraj; Choi, Ji-Won; Choi, Won-Kook; Jeong, Kwangho; Song, Jong-Han; Khan, M. Wasi; Srivastava, J. P.; Kumar, Ajay; Tandon, R. P. [Materials Science Division, Inter-University Accelerator Centre, P.O. Box 10502, Aruna Asaf Ali Marg, New Delhi 110067 (India); Thin Films Materials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650 (Korea, Republic of); Institute of Physics and Applied Physics, Yonsei University, Shincheon-dong 134, Seoul 120-749 (Korea, Republic of); Advanced Analysis Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650 (Korea, Republic of); Department of Physics, Aligarh Muslim University, Aligarh 202002 (India); Department of Physics and Astrophysics, Delhi University, Delhi 110007 (India)

2006-12-01T23:59:59.000Z

384

Fermilab | Muon Collider | How Does a Muon Collider Work?  

NLE Websites -- All DOE Office Websites (Extended Search)

A muon collider complex would comprise several machines and many different A muon collider complex would comprise several machines and many different components. Scientists across the world are developing and testing them. View full graphic How Does a Muon Collider Work? A muon collider complex would comprise several machines and many different components. Scientists across the world are developing and testing them. Proton accelerator To create lots of muons, scientists use a high-intensity proton accelerator that steers protons into a target. The collisions create short-lived particles called pions. Within 50 meters the pions decay into muons and neutral particles called neutrinos. The muons have an energy of about 200 MeV. Capture cavities Magnets guide the muons into and through a set of radiofrequency cavities. The electric field inside the cavities increases the energy of slow muons

385

The Very Large Hadron Collider: The farthest energy frontier  

E-Print Network (OSTI)

THE VERY LARGE HADRON COLLIDER: THE FARTHEST ENERGY FRONTIERAbstract The Very Large Hadron Collider (or Eloisatron)

Barletta, William A.

2001-01-01T23:59:59.000Z

386

ION ACCELERATORS AS DRIVERS FOR INERTIAL CONFINEMENT FUSION  

E-Print Network (OSTI)

and Controlled Nuclear Fusion Research, Brussels, Belgium,of the Heavy Ion Fusion Workshop held at Brookhaven NationalReport, Hearthfire Heavy Ion Fusion, October 1, 1979 - March

Faltens, A.

2010-01-01T23:59:59.000Z

387

Higgs-boson production at the Photon Collider at TESLA  

E-Print Network (OSTI)

In this thesis feasibility of the precise measurement of the Higgs-boson production cross section gamma+gamma->higgs->b+bbar at the Photon Collider at TESLA is studied in detail. The study is based on the realistic luminosity spectra simulation. The heavy quark background is estimated using the dedicated code based on NLO QCD calculations. Other background processes, which were neglected in the earlier analyses, are also studied. Also the contribution from the overlaying events, gamma+gamma->hadrons, is taken into account. The non-zero beam crossing angle and the finite size of colliding bunches are included in the event generation. The analysis is based on the full detector simulation with realistic b-tagging, and the criteria of event selection are optimized separately for each considered Higgs-boson mass. For the Standard-Model Higgs boson with mass of 120 to 160 GeV the partial width \\Gamma(h->gamma+gamma)BR(h->b+bbar) can be measured with a statistical accuracy of 2.1-7.7% after one year of the Photon Collider running. The systematic uncertainties of the measurement are estimated to be of the order of 2%. For MSSM Higgs bosons A and H, for M_A=200-350 GeV and tan(beta)=7, the statistical precision of the cross-section measurement is estimated to be 8--34%, for four considered MSSM parameters sets. As heavy neutral Higgs bosons in this scenario may not be discovered at LHC or at the first stage of the e+e- collider, an opportunity of being a discovery machine is also studied for the Photon Collider.

Piotr Niezurawski

2005-03-31T23:59:59.000Z

388

First Linear Collider ISG Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Collider Internation Study Group Workshop Full meeting proceedings Participant Photos Banquet Dinner Photos Note that you will need to have Adobe Reader 3.0 or GhostView installed...

389

Oscillation Energies of Colliding Raindrops  

Science Conference Proceedings (OSTI)

When raindrops collide, some of the kinetic energy involved in the collision will be available to initiate or sustain oscillations in the surviving drops. This paper presents results of a simple model of drop collisions that generates an estimate ...

David B. Johnson; Kenneth V. Beard

1984-04-01T23:59:59.000Z

390

How to Find a Hidden World at the Large Hadron Collider  

E-Print Network (OSTI)

I discuss how the Large Hadron Collider era should broaden our view of particle physics research, and apply this thinking to the case of Hidden Worlds. I focus on one of the simplest representative cases of a Hidden World, and detail the rich implications it has for LHC physics, including universal suppression of Higgs boson production, trans-TeV heavy Higgs boson signatures, heavy-to-light Higgs boson decays, weakly coupled exotic gauge bosons, and Higgs boson decays to four fermions via light exotic gauge bosons. Some signatures may be accessible in the very early stages of collider operation, whereas others motivate a later high-lumonosity upgrade.

James D. Wells

2008-03-08T23:59:59.000Z

391

Muon muon collider: Feasibility study  

Science Conference Proceedings (OSTI)

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup {minus}2} s{sup {minus}1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice--the authors believe--to allow them to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring which has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design.

NONE

1996-06-18T23:59:59.000Z

392

Stochastic cooling of a high energy collider  

SciTech Connect

Gold beams in RHIC revolve more than a billion times over the course of a data acquisition session or store. During operations with these heavy ions the event rates in the detectors decay as the beams diffuse. A primary cause for this beam diffusion is small angle Coloumb scattering of the particles within the bunches. This intra-beam scattering (IBS) is particularly problematic at high energy because the negative mass effect removes the possibility of even approximate thermal equilibrium. Stochastic cooling can combat IBS. A theory of bunched beam cooling was developed in the early eighties and stochastic cooling systems for the SPS and the Tevatron were explored. Cooling for heavy ions in RHIC was also considered.

Blaskiewicz, M.; Brennan, J.M.; Lee, R.C.; Mernick, K.

2011-09-04T23:59:59.000Z

393

Coherence effects in heavy ion-atom collisions. [Total cross sections, F waves, charge capture, ionization, interference, scattering amplitudes  

DOE Green Energy (OSTI)

A new approach to charge capture and ionization by highly stripped projectiles is described and shown to explain cross section systematics through the periodic table. Oscillations in cross section with respect to charge state observed around atomic number 70 are explained as an f-wave resonance in the target electron-projectile scattering. The ratio of H/sub 2/ to H cross sections for both light and heavy projectiles is shown to fit a two center coherent scattering model; independent scattering by the two centers is not a good assumption for velocities below 4 a.u. Similar coherence effects are predicted in stripping by molecular gases even in multi-electron processes where the independent atom model might be thought valid. Recent experiments on the forward peak of electrons ejected from the projectile show interesting structure which can be partly explained without invoking interference effects. 7 references.

Bottcher, C.

1978-01-01T23:59:59.000Z

394

Brouwer's problem on a heavy particle in a rotating vessel: wave propagation, ion traps, and rotor dynamics  

E-Print Network (OSTI)

In 1918 Brouwer considered stability of a heavy particle in a rotating vessel. This was the first demonstration of a rotating saddle trap which is a mechanical analogue for quadrupole particle traps of Penning and Paul. We revisit this pioneering work in order to uncover its intriguing connections with classical rotor dynamics and fluid dynamics, stability theory of Hamiltonian and non-conservative systems as well as with the modern works on crystal optics and atomic physics. In particular, we find that the boundary of the stability domain of the undamped Brouwer's problem possesses the Swallowtail singularity corresponding to the quadruple zero eigenvalue. In the presence of dissipative and non-conservative positional forces there is a couple of Whitney umbrellas on the boundary of the asymptotic stability domain. The handles of the umbrellas form a set where all eigenvalues of the system are pure imaginary despite the presence of dissipative and non-conservative positional forces.

Oleg N. Kirillov

2010-12-04T23:59:59.000Z

395

ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.  

SciTech Connect

This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linear accelerator (Linac). The highly successful development of an EBIS at Brookhaven National Laboratory (BNL) now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based preinjectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The proposed pre-injector system would also provide for a major enhancement in capability for the NASA Space Radiation Laboratory (NSRL), which utilizes heavy-ion beams from the RHIC complex. EBIS would allow for the acceleration of all important ion species for the NASA radiobiology program, such as, helium, argon, and neon which are unavailable with the present Tandem injector. In addition, the new system would allow for very rapid switching of ion species for NSRL experiments, reducing delays due to the interference with RHIC injection operations, and allowing enhanced mixed field radiation studies. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; GRANDINETTI, R.; HSEUH, H.; JAVIDFAR, A.; KPONOU, A.; LAMBIASE, R.; LESSARD, E.; LOCKEY, R.; LODESTRO, V.; MAPES, M.; MIRABELLA, D.; NEHRING, T.; OERTER, B.; PENDZICK, A.; PIKIN, A.; RAPARIA, D.; RITTER, J.; ROSER, T.; RUSSO, T.; SNYDSTRUP, L.; WILINSKI, M.; ZALTSMAN, A.; ZHANG, S.

2005-09-01T23:59:59.000Z

396

Sensitivity to the Single Production of Vector-Like Quarks at an Upgraded Large Hadron Collider  

E-Print Network (OSTI)

In this note we consider the sensitivity of the Large Hadron Collider (LHC) to the single production of new heavy vector-like quarks. We consider a model with large mixing with the standard model top quark with electroweak production of single heavy top quarks. We consider center of mass energies of 14, 33, and 100 TeV with various pileup scenarios and present the expected sensitivity and exclusion limits.

Tim Andeen; Clare Bernard; Kevin Black; Taylor Childres; Lidia Dell'Asta; Natascia Vignaroli

2013-09-07T23:59:59.000Z

397

Fake Dark Matter at Colliders  

E-Print Network (OSTI)

If the dark matter (DM) consists of a weakly interacting massive particle (WIMP), it can be produced and studied at future collider experiments like those at the LHC. The production of collider-stable WIMPs is characterized by hard scattering events with large missing transverse energy. Here we point out that the discovery of this well-characterized DM signal may turn out to be a red herring. We explore an alternative explanation -- fake dark matter -- where the only sources of missing transverse energy are standard model neutrinos. We present examples of such models, focusing on supersymmetric models with R-parity violation. We also briefly discuss means of differentiating fake dark matter from the production of new collider-stable particles.

Chang, Spencer

2009-01-01T23:59:59.000Z

398

Fake Dark Matter at Colliders  

E-Print Network (OSTI)

If the dark matter (DM) consists of a weakly interacting massive particle (WIMP), it can be produced and studied at future collider experiments like those at the LHC. The production of collider-stable WIMPs is characterized by hard scattering events with large missing transverse energy. Here we point out that the discovery of this well-characterized DM signal may turn out to be a red herring. We explore an alternative explanation -- fake dark matter -- where the only sources of missing transverse energy are standard model neutrinos. We present examples of such models, focusing on supersymmetric models with R-parity violation. We also briefly discuss means of differentiating fake dark matter from the production of new collider-stable particles.

Spencer Chang; Andre de Gouvea

2009-01-30T23:59:59.000Z

399

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

6, 27/05/99 6, 27/05/99 Tolerances of Random RF Jitters in X-Band Main Linacs May 27, 1999 Kiyoshi KUBO KEK Tsukuba, Japan Abstract: Tracking simulations have been performed for the main linacs of an X-band linear collider. We discuss the choice of phase of the accelerating field relative to the bunches. The tolerances of the phase and the amplitude errors are studied. Tolerances of Random RF Jitters in X-Band Main Linacs K. Kubo, KEK Abstract Tracking simulations have been performed for main linacs of X-band linear collider. We discuss about choice of the phase of the accelerating field relative to the bunches. The tolerances of the phase and the amplitude errors are studied. 1 INTRODUCTION In order to preserve the low emittance through the main linacs of future linear colliders, various effects

400

Large hadron collider (LHC) project quality assurance plan  

E-Print Network (OSTI)

PUB-5478-Rev.B Large Hadron Collider (LHC) Project Qualityobjectives of the Large Hadron Collider (LHC) Project in aparticipation in the Large Hadron Collider Project. The LHC/

Gullo, Lisa; Karpenko, Victor; Robinson, Kem; Turner, William; Wong, Otis

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

SIMULATION OF THE HIGGS BOSON PRODUCTION AT LHC, ILC AND PHOTON LINEAR COLLIDER ?  

E-Print Network (OSTI)

Prospects for precise determination of the Higgs boson couplings from a combined analysis of LHC, ILC and the Photon Linear Collider data are studied in detail for the CP-conserving Two Higgs Doublet Model (II). LHC, ILC and the Photon Collider measurements are complementary, being sensitive to different coupling combinations. For the mass of the heavy scalar Higgs boson between 200 and 350 GeV, where ZZ and W + W ? decaychannels dominate, only the combined analysis of the LHC, ILC and the Photon Collider data allows for unique determination of the basic Higgs boson couplings and for establishing evidence for the possible CP violation in 2HDM. Additional constraints on the model parameters can be obtained by combining available data for the production and decays of the heavy Higgs boson H with the corresponding measurements for the light Higgs boson h. PACS numbers: 11.15.Ex, 11.30.Er, 12.60.Fr, 14.80.Cp 1.

P. Nie?urawski; A. F. ?arnecki; M. Krawczyk

2006-01-01T23:59:59.000Z

402

Fusion-fission and quasifission in the reactions with heavy ions leading to the formation of Hs  

Science Conference Proceedings (OSTI)

Mass and energy distributions of binary reaction products obtained in the reactions {sup 22}Ne+{sup 249}Cf,{sup 26}Mg+{sup 248}Cm,{sup 36}S+{sup 238}U and {sup 58}Fe+{sup 208}Pb leading to Hs isotopes have been measured. At energies below the Coulomb barrier the bimodal fission of Hs*, formed in the reaction {sup 26}Mg+{sup 248}Cm, is observed. In the reaction {sup 36}S+{sup 238}U the considerable part of the symmetric fragments arises from the quasifission process. At energies above the Coulomb barrier the symmetric fragments originate mainly from fusion-fission process for both reactions with Mg and S ions. In the case of the {sup 58}Fe+{sup 208}Pb reaction the quasifission process dominates at all measured energies. The pre- and post-scission neutron multiplicities as a function of the fragment mass have been obtained for the reactions studied.

Itkis, I. M.; Itkis, M. G.; Knyazheva, G. N.; Kozulin, E. M. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

2012-10-20T23:59:59.000Z

403

Fission and quasifission modes in heavy-ion-induced reactions leading to the formation of Hs{sup *}  

SciTech Connect

Mass and energy distributions of binary reaction products obtained in the reactions {sup 22}Ne+{sup 249}Cf,{sup 26}Mg+{sup 248}Cm, {sup 36}S+{sup 238}U, and {sup 58}Fe+{sup 208}Pb have been measured. All reactions lead to Hs isotopes. At energies below the Coulomb barrier the bimodal fission of Hs{sup *}, formed in the reaction {sup 26}Mg+{sup 248}Cm, is observed. In the reaction {sup 36}S+{sup 238}U, leading to the formation of a similar compound nucleus, the main part of the symmetric fragments arises from the quasifission process. At energies above the Coulomb barrier fusion-fission is the main process leading to the formation of symmetric fragments for both reactions with Mg and S ions. In the case of the {sup 58}Fe+{sup 208}Pb reaction the quasifission process dominates at all measured energies.

Itkis, I. M.; Kozulin, E. M.; Itkis, M. G.; Knyazheva, G. N.; Bogachev, A. A.; Chernysheva, E. V.; Krupa, L.; Oganessian, Yu. Ts.; Zagrebaev, V. I.; Rusanov, A. Ya.; Goennenwein, F.; Dorvaux, O.; Stuttge, L.; Hanappe, F.; Vardaci, E.; Goes Brennand, E. de [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute of Nuclear Physics of the National Nuclear Center of Kazakhstan, 050032 Almaty (Kazakhstan); Physikalisches Institut, Universitaet Tuebingen, D-72076 Tuebingen (Germany); Institut Pluridisciplinaire Hubert Curien and Universite de Strasbourg, F-67037 Strasbourg (France); Universite Libre de Bruxelles, CP229, B-1050 Bruxelles, Belgique (Belgium); Istituto Nazionale di Fisica Nucleare and Dipartimento di Scienze Fisiche dell'Universita di Napoli, Napoli (Italy); Departamento de Fisica, Universidade Estadual da Paraiba, 58109-753 Campina Grande (Brazil)

2011-06-15T23:59:59.000Z

404

Predicting Large Hadron Collider Observations using Kazuo Kondo's Mass Quantum Cascade  

E-Print Network (OSTI)

The late Kazuo Kondo left a hitherto unknown a priori particle theory which provides predictions of massive particles which may be detected by the Large Hadron Collider (LHC). This article briefly introduces Kondo's work and documents the derivation and masses of his expected hyper-mesons, hyper-hadrons, heavy leptons and massive neutrinos. Several particles in these classes may have already been detected.

Grenville J. Croll

2008-04-27T23:59:59.000Z

405

Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach  

E-Print Network (OSTI)

We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central ($b\\leq 2.75$ fm) Pb+Pb/Au+Au collisions from $E_{lab}=2A$ GeV to $\\sqrt{s_{NN}}=200$ GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low $\\sqrt{s_{NN}}$.

Marlene Nahrgang; Tim Schuster; Michael Mitrovski; Reinhard Stock; Marcus Bleicher

2009-03-17T23:59:59.000Z

406

Higgs Boson Production with Heavy Quarks at Hadron Colliders.  

E-Print Network (OSTI)

?? One of the remaining puzzles in particle physics is the origin of electroweak symmetry breaking. In the Standard Model (SM), a single doublet of (more)

Jackson, Christopher B.

2005-01-01T23:59:59.000Z

407

Heavy-quark production at large rapidities at hadron colliders.  

E-Print Network (OSTI)

to those partonic subprocesses that feature a gluon exchange in the t-channel; this happens for gg ? QQg and qg ? QQq, and it is peculiar to the NLO computations of quark pair production, as opposed to Born-level predictions, in which only fermions... -energy limit is QQ+1 jet production. In this case the partonic subprocesses gg ? QQg and qg ? QQq, which feature a gluon exchange in the t-channel, are O(?3S) at the Born level. This can also be considered as a reformulation of the standard Mueller...

Andersen, Jeppe R; Del Duca, Vittoria; Frixione, Stefano; Maltoni, Fabio; Stirling, W James

408

JOURNAL DE PHYSIQUE Colloque C5, supplment au n \\\\, Tome 37., Novembre 1976., page C5-237 THE HEAVY ION FACILITY V I C K S I AT BERLIN  

E-Print Network (OSTI)

- und Strahlenphysik, H a h n - M e i t ~ r I n s t i t u t , Wissenschaftlicher Ergebnisbericht 1, 1974-237 THE HEAVY ION FACILITY V I C K S I AT BERLIN VICKSI-Group, presented t>y K. H. Lindenberger Bereich Kern' /3/ D. Hilscher e t a l . , IEEE Trans. Nucl. Sci. NS-22, No. 3, June 75, p. 1643 /4/ Bereich Kern

Paris-Sud XI, Université de

409

Higgs Boson Search at e + e ? and Photon Linear Colliders ?  

E-Print Network (OSTI)

The various search modes for the Higgs bosons of the Standard Model (SM) and its Minimal Supersymmetric Extension (MSSM) at the International Linear Collider (ILC) will be summarized briefly. In particular, as a unique discovery mode the production of heavy neutral MSSM Higgs bosons for medium values of tan? in photon collisions will be presented. Furthermore, ? + ? ? fusion into MSSM Higgs bosons in the photon mode will be shown to give access to the mixing parameter tan ? with a precision of better than 10 % for large values of this parameter. PACS numbers: 12.15.-y, 12.60.-i 1.

M. M. Mhlleitner

2005-01-01T23:59:59.000Z

410

Atomic Physics Aspects of a Relativistic Nuclear Collider  

DOE Green Energy (OSTI)

Atomic collision cross sections involving bare uranium nuclei are large at relativistic energies and will affect the design and operation of a relativistic nuclear collider (RNC). The most significant may be production of electron-positron pairs and muon pairs ({approx} 10{sup 8} per sec. and 2000 per sec. respectively for a 100 GeV/nucleon collider with a luminosity of 10{sup 27} cm{sup 2} s{sup -1}). Although the pair production is a direct measure of the luminosity it is also a large source of background and capture of an electron from the pair by one of the nuclei will result in the loss of the ion. Another important loss mechanism is Coulomb excitation of the giant nuclear dipole and giant nuclear quadrupole resonances. Storing and colliding bare and highly-stripped uranium opens up new possibilities for novel atomic physics experiments and an alternate approach for present experiments. As examples, the use of a collider for experiments to study spontaneous decay of the super-critical state (both positron production and x-ray production) of quasi-atoms of atomic number Z > 172, and a storage-ring measurement of the ground state hyperfine structure of hydrogen like thallium as a test of quantum electrodynamics (QED) are discussed.

Gould, R.

1984-11-01T23:59:59.000Z

411

What product might a renewal of Heavy IonFusion development offerthat competes with methane microbes and hydrogen HTGRs  

DOE Green Energy (OSTI)

In 1994 a Fusion Technology journal publication by Logan, Moir and Hoffman described how exploiting unusually-strong economy-of-scale for large (8 GWe-scale) multi-unit HIF plants sharing a driver and target factory among several low cost molten salt fusion chambers {at} < $40M per 2.4 GW fusion each (Fig. 1), could produce electricity below 3 cts/kWehr, even lower than similar multi-unit fission plants. The fusion electric plant could cost $12.5 B for 7.5 GWe and produce hydrogen fuel by electrolysis at prices competitive with gasoline-powered hybrids getting fuel from oil at $20$/bbl. At $60/bbl oil, the fusion plant can cost $35B and compete {at} 10% APR financing. Given massive and still-increasing world demand for transportation fuel even with oil climbing above $60/bbl, large HIF plants producing both low cost electricity and hydrogen could be more relevant to motivate new R&D funding for HIF development in the next few years. Three major challenges to get there: (1) NIF ignition in indirect drive geometry for liquid chambers, (2) a modular accelerator to enable a one-module IRE < $100 M, (3) compatible HIF target, driver and chamber allowing a small driver {at}< $500 M cost for a >100MWe net power DEMO. This scoping study, at a very preliminary conceptual level, attempts to identify how we might meet the last two great challenges taking advantage of several recent ideas and advances which motivate reconsideration of modular HIF drivers: >60X longitudinal compression of neutralized ion beams using a variable waveform induction module in NDCX down to 2 nanosecond bunches, the proof-of-principle demonstration of fast optical-gated solid state SiC switches by George Caporaso's group at LLNL (see George's RPIA06 paper), and recent work by Ed Lee, John Barnard and Hong Qin on methods for time-dependent correction of chromatic focusing errors in neutralized beams with up to 10 % {Delta}v/v velocity tilt, allowing 5 or more bunches, and shorter bunches, and possibly < 1 mm radius focal spot targets. We seek multi-pulsing with neutralized compression and focusing to enable higher peak power capability and the ability to create nearly arbitrary composite ''picket fence'' pulse shapes can be used to innovate HIF target designs for lower driver energy, and at the same time, reduce unit driver cost per joule for given driver energy, and reduce development time. For example, Debbie Callahan has explored close-coupled HIF targets with adequate gains > 40 that would need higher peak beam intensities in order to reduce total driver energy below 1 MJ. In principle, both PLIA and induction accelerators might benefit from multiple short bunches (see June 24, 2005 talk by Logan on multi-pulsing in PLIA accelerators for IFE), although the PLIA approach, because of fixed circuit wave velocities at any z, requires imaginative work-arounds to handle the different bunch velocities required. George's RPIA06 paper also describes a different type of radial line induction linac that might be considered, but its unclear how the required pulse-to-pulse variable waveforms can be obtained with such pulselines. This initial MathCad analysis explores multi-pulsing in modular solenoid induction linacs (concept shown in Figure 1) considering high-q ECR sources, basic induction acceleration limits assuming affordable agile waveforms, transverse and longitudinal bunch confinement constraints, models to optimize bunch lengths, solenoid fields, core radial builds and switching. Figure 2 below illustrates one linac module for a driver example (not yet optimized) consisting of 40 linacs (20 at each end). Necessarily, this first look invokes many new ideas, but could they potentially meet the above challenges?

Logan, Grant; Lee, Ed; Yu, Simon; Briggs, Dick; Barnard, John; Friedman, Alex; Qin, Hong; Waldron, Will; Leitner, Mattaheus; Kwan, Joe; Henestroza, Enrique; Caporaso, George; Meier, Wayne; Tabak, Max; Callahan, Debbie; Moir, Ralph; Peterson, Per

2006-04-19T23:59:59.000Z

412

Heavy ion fusion--Using heavy ions to make electricity  

E-Print Network (OSTI)

as a source of commercial electrical power has been pursuedfusion to produce commercial electrical power has been anpower plant output would be high ? 2 GW); high electrical

Celata, C.M.

2004-01-01T23:59:59.000Z

413

Suppression of high-p{sub T} hadrons in Pb+Pb collisions at energies available at the CERN Large Hadron Collider  

Science Conference Proceedings (OSTI)

The nuclear modification factor R{sub AA}(p{sub T}) for large transverse momentum pion spectra in Pb+Pb collisions at {radical}(s)=2.76 TeV is predicted within the next-to-leading order perturbative QCD parton model. The effect of jet quenching is incorporated through medium-modified fragmentation functions within the higher-twist approach. The jet transport parameter that controls medium modification is proportional to the initial parton density, and the coefficient is fixed by data on the suppression of large-p{sub T} hadron spectra obtained at the BNL Relativistic Heavy Ion Collider. Data on charged hadron multiplicity dN{sub ch}/d{eta}=1584{+-}80 in central Pb+Pb collisions from the ALICE experiment at the CERN Large Hadron Collider are used to constrain the initial parton density both for determining the jet transport parameter and the 3 + 1 dimensional (3 + 1D) ideal hydrodynamic evolution of the bulk matter that is employed for the calculation of R{sub PbPb}(p{sub T}) for neutral pions.

Chen Xiaofang; Wang Enke; Zhang Hanzhong [Institute of Particle Physics, Huazhong Normal University, Wuhan 430079 (China); Hirano, Tetsufumi [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Nuclear Science Division, MS 70R0319, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Wang Xinnian [Institute of Particle Physics, Huazhong Normal University, Wuhan 430079 (China); Nuclear Science Division, MS 70R0319, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2011-09-15T23:59:59.000Z

414

Probing Higgs Boson Interactions At Future Colliders.  

E-Print Network (OSTI)

??We present in this thesis a detailed analysis of Higgs boson interactions at future colliders. In particular we examine, in a model independent way, the (more)

Biswal, Sudhansu Sekhar

2009-01-01T23:59:59.000Z

415

Links to Muon Collider Related Web Pages  

NLE Websites -- All DOE Office Websites (Extended Search)

useful nu-factory related web pages: Nu-FactoryMuon Collider Studies at Fermilab Neutrino Factory Design Study MUCOOL Collaboration: Ionization Cooling R&D Brookhaven Muon...

416

Siting the International Linear Collider at Hanford  

SciTech Connect

Review of the proposed International Linear Collider, applications in high energy physics, and evaluation of the Hanford Site as a possible location for siting the facilityl.

Kouzes, Richard T.; Asner, David M.; Brodzinski, Ronald L.; Fast, James E.; Miley, Harry S.

2012-03-15T23:59:59.000Z

417

Siting the International Linear Collider at Hanford  

SciTech Connect

Review of the proposed International Linear Collider, applications in high energy physics, and evaluation of the Hanford Site as a possible location for siting the facility.

Kouzes, Richard T.; Asner, David M.; Brodzinski, Ronald L.; Fast, James E.; Miley, Harry S.

2012-05-01T23:59:59.000Z

418

Subcritical Fission Reactor Based on Linear Collider  

E-Print Network (OSTI)

The beams of Linear Collider after main collision can be utilized to build an accelerator--driven sub--critical reactor.

I. F. Ginzburg

2005-07-29T23:59:59.000Z

419

The Next Linear Collider Program  

NLE Websites -- All DOE Office Websites (Extended Search)

To use the left side navigation on this page, you will need to turn on To use the left side navigation on this page, you will need to turn on Javascript. You do not need JavaScript to use the text-based navigation bar at the bottom of the page. The Next Linear Collider at SLAC Navbar MISSION: Scientists expect research at this facility to answer fundamental questions about the behavior of matter and the origins of the Universe. NLC 8-Pack on the Drawing Board What's New In the Next Linear Collider: • NLC Newsletter October, 2001 • NLC Snowmass report 2001 • NLC All Hands Talk, August 2001 Upcoming Events: • Fall 2001 Working Sessions, Oct. 22-23, 2001 • Pulse Compression Workshop, Oct. 22-24, 2001 • Machine Advisory Committee Mtg., Oct. 24-26, 2001 • ISG-7 at KEK, Nov. 12-15, 2001 • LC' 02 at SLAC, Feb. 4-8, 2002 NLC Website Search: Entire SLAC Web | Help |

420

Stochastic cooling in muon colliders  

SciTech Connect

Analysis of muon production techniques for high energy colliders indicates the need for rapid and effective beam cooling in order that one achieve luminosities > 10{sup 30} cm{sup {minus}2}s{sup {minus}1} as required for high energy physics experiments. This paper considers stochastic cooling to increase the phase space density of the muons in the collider. Even at muon energies greater than 100 GeV, the number of muons per bunch must be limited to {approximately}10{sup 3} for the cooling rate to be less than the muon lifetime. With such a small number of muons per bunch, the final beam emittance implied by the luminosity requirement is well below the thermodynamic limit for beam electronics at practical temperatures. Rapid bunch stacking after the cooling process can raise the number of muons per bunch to a level consistent with both the luminosity goals and with practical temperatures for the stochastic cooling electronics. A major advantage of our stochastic cooling/stacking scheme over scenarios that employ only ionization cooling is that the power on the production target can be reduced below 1 MW.

Barletta, W.A.; Sessler, A.M.

1993-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Effects of momentum-dependent nuclear potential on two-nucleon correlation functions and light cluster production in intermediate energy heavy-ion collisions RID A-2398-2009  

E-Print Network (OSTI)

Using an isospin- and momentum-dependent transport model, we study the effects due to the momentum dependence of isoscalar nuclear potential as well as that of symmetry potential on two-nucleon correlation functions and light cluster production in intermediate energy heavy-ion collisions induced by neutron-rich nuclei. It is found that both observables are affected significantly by the momentum dependence of nuclear potential, leading to a reduction of their sensitivity to the stiffness of nuclear symmetry energy. However, the t/He-3 ratio remains a sensitive probe of the density dependence of nuclear symmetry energy.

Chen, LW; Ko, Che Ming; Li, Ba.

2004-01-01T23:59:59.000Z

422

Research and Development of Future Muon Collider  

SciTech Connect

Muon collider is a considerable candidate of the next generation high-energy lepton collider machine. A novel accelerator technology must be developed to overcome several intrinsic issues of muon acceleration. Recent research and development of critical beam elements for a muon accelerator, especially muon beam phase space ionization cooling channel, are reviewed in this paper.

Yonehara, K.; /Fermilab

2012-05-01T23:59:59.000Z

423

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

NLC Home Page NLC Technical SLAC The LCC Tech Note series was started in July 1998 to document the JLC/NLC collaborative design effort. The notes are numbered sequentially and may also be given a SLAC, FNAL, LBNL, LLNL and/or KEK publication number. The LCC notes will be distributed through the Web in electronic form as PDF files -- the authors are responsible for keeping the original documents. Other document series are the NLC Notes that were started for the SLAC ZDR, the KEK ATF Notes, and at some future time there should be a series of Technical (NLD) Notes to document work on detector studies for the next-generation linear collider. LCC-0001 "Memorandum of Understanding between KEK and SLAC," 2/98. LCC-0002 "Transparencies and Summaries from the 1st ISG meeting: January 1998," G. Loew, ed., 2/98.

424

Heavy flavour physics from top to bottom  

SciTech Connect

We review the status of heavy flavour physics at the Fermilab Tevatron collider by summarizing recent top quark and B physics results from CDF and D0. In particular we discuss the measurement of the top quark mass and top production cross section as well as B meson lifetimes and time dependent B{anti B} mixing results. An outlook of perspectives for top and B physics in Run II starting in 1999 is also given.

Paulini, M. [Lawrence Berkeley National Lab., CA (United States); CDF and D0 Collaboration

1998-02-01T23:59:59.000Z

425

Parametic Study of the current limit within a single driver-scale transport beam line of an induction Linac for Heavy Ion Fusion  

E-Print Network (OSTI)

Physics of Magnetic Fusion Reactors, Rev. of Modern Physicsheavy ion beam driven fusion reactor study, Technical Reporta toroidally shaped fusion reactor (tokamak) such as shown

Prost, Lionel Robert

2007-01-01T23:59:59.000Z

426

eta_c production at the Large Hadron Collider  

E-Print Network (OSTI)

We have studied the production of the 1S_0 charmonium state, eta_c, at the Large Hadron Collider (LHC) in the framework of Non-Relativistic Quantum Chromodynamics (NRQCD) using heavy-quark symmetry. We find that NRQCD predicts a large production cross-section for this resonance at the LHC even after taking account the small branching ratio of eta_c into two photons. We show that it will be possible to test NRQCD through its predictions for eta_c, with the statistics that will be achieved at the early stage of the LHC, running at a center of mass energy of 7 TeV with an integrated luminosity of 100 pb^{-1}

Sudhansu S. Biswal; K. Sridhar

2010-07-29T23:59:59.000Z

427

Electroweak and flavor dynamics at hadron colliders - I  

SciTech Connect

This is the first of two reports cataloging the principal signatures of electroweak and flavor dynamics at {anti p}p and pp colliders. Here, we discuss some of the signatures of dynamical electroweak and flavor symmetry breaking. The framework for dynamical symmetry breaking we assume is technicolor, with a walking coupling {alpha}{sub TC}, and extended technicolor. The reactions discussed occur mainly at subprocess energies {radical}{cflx s}{approx_lt} 1 TeV. They include production of color-singlet and octet technirhos and their decay into pairs of technipions, longitudinal weak bosons, or jets. Technipions, in turn, decay predominantly into heavy fermions. This report will appear in the Proceedings of the 1996 DPF/DPB Summer Study on New Directions for High Energy Physics (Snowmass 96).

Elchtent, E.; Lane, K. [Boston Univ., MA (United States)

1998-02-01T23:59:59.000Z

428

X-ray emission from colliding laser plasmas  

SciTech Connect

Colliding Au, CD and Ti-Cr plasmas have been generated by illuminating two opposing foils each with a {approximately} 100J, 0.5 nsec, 2{omega} Nd-glass laser beam from the Trident laser facility at Los Alamos. The plasmas are being used to study plasma interactions which span the parameter regime from interpenetrating to collisional stagnation. X-ray emission during the laser target interaction and the subsequent collision is used to diagnose the initial plasma conditions and the colliding plasma properties. X-ray instrumentation consists of a 100 ps gated x-ray pinhole imager, a time-integratcd bremsstrahlung x-ray spectrograph and a gated x-ray spectrograph used to record isoelectronic spectra from the Ti-Cr plasmas. The imager has obtained multi-frame images of the collision and therefore, a measure of the stagnation length which is a function of the ion charge state and density and a strong function of the electron temperature. Other instrumentation includes a Thomson scattering spectrometer with probe beam, neutron detectors used to monitor the CD coated foil collisions and an ion spectrometer. We will describe the current status of the experiments and current results with emphasis on the x-ray emission diagnostics. We will also briefly describe the modeling using Lasnex and ISIS, a particle-in-cell code with massless fluid electrons and inter particle (classical) collisions.

Wilke, M.; Obst, A.W.; Winske, D. [and others

1995-09-01T23:59:59.000Z

429

The Large Hadron Electron Collider Project  

E-Print Network (OSTI)

A Conceptual Design Report (CDR) for the Large Hadron Electron Collider, the LHeC, is being prepared, to which an introduction was given for the plenary panel discussion on the future of deep inelastic scattering held at DIS09. This is briefly summarised here. The CDR will comprise designs of the ep/eA collider, based on ring and linear electron accelerators, of the interaction region, designed for simultaneous $ep$ and $pp$ operation, of a new, modular detector, and it will present basics on the physics motivation for a high luminous Tera scale electron-nucleon collider as a complement to the LHC.

Max Klein

2009-08-20T23:59:59.000Z

430

Decoupling schemes for the SSC Collider  

Science Conference Proceedings (OSTI)

A decoupling system is designed for the SSC Collider. This system can accommodate three decoupling schemes by using 44 skew quadrupoles in the different configurations. Several decoupling schemes are studied and compared in this paper.

Cai, Y.; Bourianoff, G.; Cole, B.; Meinke, R.; Peterson, J.; Pilat, F.; Stampke, S.; Syphers, M.; Talman, R.

1993-05-01T23:59:59.000Z

431

Fermilab Now - LHC Large Hadron Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Hadron Collider (LHC) Over the next few months, a 12,500-ton detector will be lowered almost 300 feet below ground near the French-Swiss border. Dubbed "CMS," this detector...

432

Final Scientific and Technical Report for Grant DE-FG02-99ER41099 Entitled Study the Collective Behavior of Quarks and Gluons in High Energy Nuclear Collisions  

SciTech Connect

This is the final technical/scientific report for a heavy ion research program on the PHOBOS experiment at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory.

Steven Manly

2008-09-08T23:59:59.000Z

433

Higgs Physics at the Large Hadron Collider  

E-Print Network (OSTI)

A major goal of the future Large Hadron Collider will be the Higgs boson search. In this paper the discovery In this paper the discovery potential is described as a function of the Higgs mass showing that a Standard Model Higgs boson can be discovered after less than two years of running of the collider. The MSSM Higgs searches and the precision achievable on the measurement of the Higgs boson parameters are also discussed.

Davide Costanzo

2001-05-15T23:59:59.000Z

434

Photon Linear Collider Gamma-Gamma Summary  

SciTech Connect

High energy photon - photon collisions can be achieved by adding high average power short-pulse lasers to the Linear Collider, enabling an expanded physics program for the facility. The technology required to realize a photon linear collider continues to mature. Compton back-scattering technology is being developed around the world for low energy light source applications and high average power lasers are being developed for Inertial Confinement Fusion.

Gronberg, J

2012-02-27T23:59:59.000Z

435

The promise of the large collider  

E-Print Network (OSTI)

"In 2007, the most powerful particle accelerator ever built, CERN's new Large hadron Collider, will probe the secrets of matter in the energy states prevailing in the moments after the Big Bang. By colliding particles together when they are moving at close to the speed of ight, physicists hope to find out about matter in its earliest forms, using the energy produced by the collisions." (2 pages)

2007-01-01T23:59:59.000Z

436

Swift heavy ion irradiation-induced microstructure modification on two delta-phase oxides: Sc4Zr3O12 and Lu4Zr3O12  

Science Conference Proceedings (OSTI)

Swift gold ions (185 MeV) were used to systematically investigate the radiation damage response of delta phase compounds Sc{sub 4}Zr{sub 3}O{sub 12} and Lu{sub 4}Zr{sub 3}O{sub 12} in the electronic energy loss regime. Ion irradiation-induced microstructural modifications were examined using X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD investigations indicate a phase transformation from ordered rhombohedral to disordered fluorite (O-D) in both compounds, with the Sc compound transforming at a higher ion fluence compared with the Lu compound. This result is consistent with our previous study on Sc{sub 4}Zr{sub 3}O{sub 12} and Lu{sub 4}Zr{sub 3}O{sub 12} under displacive radiation environment in which the nuclear energy loss is dominant. High resolution TEM revealed that individual ion tracks maintains crystalline structure where the core region experiences an O-D phase transformation. TEM observation also suggests that the O-D phase transformation occurs through the ion range after overlapping of ion tracks.

Tang, Ming [Los Alamos National Laboratory; Zhang, Jian [Los Alamos National Laboratory; Uberuaga, Blas P [Los Alamos National Laboratory; Sickafus, Kurt E [Los Alamos National Laboratory; Reichhardt, Cynthia J [Los Alamos National Laboratory; Kluth, Patrick [AUSTRALIA; Maulik, Patel [INDIA

2009-01-01T23:59:59.000Z

437

Heavy Oil Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

Select Reports from Heavy Oil Projects Project Number Performer Title Heavy Oil Recovery US (NIPERBDM-0225) BDM-Oklahoma, Inc. Feasibility Study of Heavy Oil Recovery in the...

438

Charged hadron transverse momentum spectra in Au+Au and d+Au collisions at 200 GeV per nucleon pair  

E-Print Network (OSTI)

The Relativistic Heavy Ion Collider (RHIC) collides Au ions at a center of mass energy of 200 GeV per nucleon pair, which produces the most energetic collisions yet seen in the laboratory. RHIC has also collided proton ...

Kane, Jay Lawrence

2005-01-01T23:59:59.000Z

439

A Nuclear Physics Program at the ATLAS Experiment at the CERN Large Hadron Collider  

E-Print Network (OSTI)

The ATLAS collaboration has significant interest in the physics of ultra-relativistic heavy ion collisions. We submitted a Letter of Intent to the United States Department of Energy in March 2002. The following document is a slightly modified version of that LOI. More details are available at: http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/SM/ions

S. Aronson; K. Assamagan; H. Gordon; M. Leite; M. Levine; P. Nevski; H. Takai; S. White; B. Cole; J. L. Nagle

2002-12-13T23:59:59.000Z

440

Brookhaven and the Large Hadron Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Brookhaven & the Large Hadron Collider Brookhaven & the Large Hadron Collider Home News Brookhaven & ATLAS ATLAS ATLAS Calorimeter ATLAS Muon Spectrometer Construction Computing Upgrades RHIC & LHC Education LHC tunnel ATLAS detector ATLAS detector RACF BNL built superconducting magnets Brookhaven & the LHC The world's most powerful particle accelerator, the Large Hadron Collider (LHC) in Switzerland, powers unprecedented explorations of the deepest mysteries of the universe. In addition to serving as the U.S. host laboratory for the ATLAS experiment at the LHC, Brookhaven National Lab plays multiple roles in this international collaboration, from construction and project management to data storage and distribution. ATLAS rendering Brookhaven and ATLAS Brookhaven physicists and engineers are participating in one of the most

Note: This page contains sample records for the topic "heavy ion collider" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Linear Collider Collaboration Tech Notes LCC-0100  

NLE Websites -- All DOE Office Websites (Extended Search)

100 100 August 2002 Systematic Ground Motion and Macroalignment for Linear Colliders Rainer Pitthan Stanford Linear Accelerator Center Stanford University Stanford, CA 94309, USA Abstract: Future colliders with their µm-range operational tolerances still need to be classically aligned to the 50 - 100 µm range, and kept there, over the km range. This requirement will not be a show-stopper, but not be trivial either. 50 µm movements over a betatron wavelength is a the range where systematic long term motions can prevent efficient operation. Systematic Ground Motion and Macro-Alignment for Linear Colliders Complete talk at: http://www-project.slac.stanford.edu/lc/wkshp/snowmass2001/t6/info/pitthan july

442

Fermilab | Muon Collider | Reports and Papers  

NLE Websites -- All DOE Office Websites (Extended Search)

Reports and Papers Reports and Papers Comprehensive Reports J. Gallardo, R. Palmer, A. Tollestrup, A. Sessler, A. Skrinsky et al., "μ+ μ- Collider: A Feasibility Study," DPF/DPB Summer Study on New Directions for High Energy Physics, Snow- mass, Colorado, 25 Jun - 12 Jul 1996, BNL - 52503, Fermilab - Conf - 96 - 092, LBNL - 38946, http://www.cap.bnl.gov/mumu/pubs/snowmass96.html C. Ankenbrandt et al.,"Status of muon collider research and development and future plans," Phys. Rev. ST Accel. Beams 2 (1999) 081001, http://prst-ab.aps.org/abstract/PRSTAB/v2/i8/e081001 M. M. Alsharo'a et al., "Recent progress in neutrino factory and muon collider research within the Muon Collaboration," Phys. Rev. ST Accel. Beams 6 (2003) 081001, http://prst-ab.aps.org/abstract/PRSTAB/v6/i8/e081001

443

Properties of Jets Measured with Charged Particles with the ATLAS Detector at the Large Hadron Collider  

E-Print Network (OSTI)

3 The Large Hadron Collider and ATLAS3.1 The Large Hadron Collider Complex . . . . . . . .of QCD at the Large Hadron Collider. These improvements will

Zenz, Seth Conrad

2011-01-01T23:59:59.000Z

444

Microsoft Word - WFnote-238_Summary of short pulse collider.doc  

NLE Websites -- All DOE Office Websites (Extended Search)

electron-positron linear collider from the International Linear Collider (ILC) and Compact Linear Collider (CLIC) teams have been well established. Both proposed machines work...

445

International linear collider reference design report  

Science Conference Proceedings (OSTI)

The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

Aarons, G.

2007-06-22T23:59:59.000Z

446

Challenging the standard model at the Tevatron collider  

SciTech Connect

Even at a time where the world's eyes are focused on the Large Hadron Collider at CERN, which has reached the energy frontier in 2010, many important results are still being obtained from data analyses performed at the Tevatron collider at Fermilab. This contribution discusses recent highlights in the areas of B hadron, electroweak, top quark, and Higgs boson physics. The standard model (SM) of particle physics forms the cornerstone of our understanding of elementary particles and their interactions, and many of its aspects have been investigated in great detail. Yet it is generally suspected to be incomplete (e.g. by not allowing for the incorporation of gravity in a field theoretical setting) and un-natural (e.g. the mass of the Higgs boson is not well protected against radiative corrections). In addition, it does not explain the dark matter and dark energy content of the Universe. It is therefore of eminent importance to test the limits of validity of the SM. In the decade since its upgrade to a centre-of-mass energy {radical}s = 1.96 TeV, the Tevatron p{bar p} collider has delivered an integrated luminosity of about 10 fb{sup -1}, up to 9 fb{sup -1} of which are available for analysis by its CDF and D0 collaborations. These large datasets allow for stringent tests of the SM in two areas: direct searches for particles or final states that are not very heavy but that suffer from small production cross sections (e.g. the Higgs boson), and searches for indirect manifestations of beyond-the-standard-model (BSM) effects through virtual effects. The latter searches can often be carried out by precise measurements of otherwise known processes. This contribution describes such tests of the SM carried out by the CDF and D0 collaborations. In particular, recent highlights in the areas of B hadron physics, electroweak physics, top quark physics, and Higgs boson physics are discussed. Recent results of tests of QCD and of direct searches for new phenomena are described in another contribution.

Filthaut, Frank; /Nijmegen U.

2011-03-01T23:59:59.000Z

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Challenging the standard model at the Tevatron collider  

SciTech Connect

Even at a time where the world's eyes are focused on the Large Hadron