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Sample records for heavy-ion nucleon transfers

  1. Probing nucleon-nucleon correlations in heavy-ion transfer reactions

    Directory of Open Access Journals (Sweden)

    Szilner S.

    2016-01-01

    Full Text Available The γ-particle coincident measurements, performed by coupling of the PRISMA spectrometer to the large γ arrays (CLARA and AGATA, demonstrate a strong interplay between single-particle and collective degrees of freedom that is pertinent to the reaction dynamics. By using the unique PRISMA performance in terms of both resolution and efficiency, measurements at very low bombarding energies have been performed. Via transfer of nucleon pairs, valuable information on the component responsible for particle correlations has been derived.

  2. Subbarrier heavy ion fusion enhanced by nucleon transfer and subbarrier fusion of nuclei far from the line of {beta}-stability

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, V.Yu. [Institute for Nuclear Research, Kiev (Ukraine)]|[Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)

    1998-09-01

    We discuss a model for the description of subbarrier fusion of heavy ions which takes into account the coupling to the low-energy surface vibrational states and to the few-nucleon transfer with arbitrary reaction Q-value. The fusion reactions {sup 28,30}Si+{sup 58,62,64}Ni, {sup 40}Ca+{sup 90,96}Zr, {sup 28}S+{sup 94,100}Mo, {sup 16,18,20,22,24}O+{sup 58}Ni and {sup 28}Si+{sup 124,126,128,130,132}Sn are analyzed in detail. The model describes rather well the experimental fusion cross section and mean angular momentum for reactions between nuclei near the {beta}-stability line. It is shown that these quantities are significantly enhanced by few-nucleon transfer with large positive Q-value. A shape independent parameterization of the heavy ion potential at distances smaller then the touching point is proposed. (orig.)

  3. Heavy ion transfer reactions: Status and perspectives

    Indian Academy of Sciences (India)

    respond to the transfer of two neutrons in the p3/2 orbital, and we remind that the single-particle form-factors for the p3/2 orbital is much larger than the one for the .... trajectory. The imaginary potential W(r), that describes the depopulation of the entrance channel, at very low energies is dominated by the single-nucleon ...

  4. Closed form S matrix in terms of matter distributions and nucleon-nucleon interaction for heavy ion scattering

    Energy Technology Data Exchange (ETDEWEB)

    Gambhir, Y.K.; Shastry, C.S.

    1984-10-01

    We derive an approximate analytical expression for the S matrix in terms of the parameters of the nuclear matter distributions and nucleon-nucleon interaction in the framework of folding model for heavy ion scattering. The numerical calculations carried out for /sup 18/O+ /sup 58/Ni scattering (E/sub lab/ = 60 MeV), a test case, agree well with the corresponding results of the phenomenological optical model.

  5. Nuclear fragmentation energy and momentum transfer distributions in relativistic heavy-ion collisions

    Science.gov (United States)

    Khandelwal, Govind S.; Khan, Ferdous

    1989-01-01

    An optical model description of energy and momentum transfer in relativistic heavy-ion collisions, based upon composite particle multiple scattering theory, is presented. Transverse and longitudinal momentum transfers to the projectile are shown to arise from the real and absorptive part of the optical potential, respectively. Comparisons of fragment momentum distribution observables with experiments are made and trends outlined based on our knowledge of the underlying nucleon-nucleon interaction. Corrections to the above calculations are discussed. Finally, use of the model as a tool for estimating collision impact parameters is indicated.

  6. Three-nucleon interaction in heavy-ion collisions at intermediate energies

    Science.gov (United States)

    Wada, R.

    2017-09-01

    The effect of a three-nucleon (3 N ) interaction is studied for the production of high energy protons in heavy-ion collisions in the incident energy range of 44 to 400 A MeV . The 3 N interaction is incorporated into the antisymmetrized molecular dynamics transport model of Ono [A. Ono, Phys. Rev. C 59, 853 (1999), 10.1103/PhysRevC.59.853] as a 3 N collision term, following a diagram of three consecutive binary collisions. For the theoretical 40Ar+51V reaction studies, no contribution from the 3 N collisions is observed for high energy proton production at the incident energy of 44 A MeV . However when the incident energy increases, the contribution increases gradually. At 200 A MeV and above, the contribution is observed as distinctly harder energy slopes in the proton energy spectra. The model is applied to the available Bevalac data for 40Ar+40Ca at 42 ,92 , and 137 A MeV . The experimental proton energy spectra are reasonably well reproduced at angles θ ≥70∘ for all three incident energies, showing negligible 3 N contributions at 42 A MeV and significant contributions at 137 A MeV at the large laboratory angles. Good agreement at these large angles, where the 3 N collision is a major mechanism to produce such protons, strongly indicates for the first time the importance of the 3 N interaction in intermediate heavy ion reactions in a full transport calculation. The possible relation between the 3 N collision term and the short range and the tensor interactions is suggested.

  7. Systematic comparison of barriers for heavy-ion fusion calculated on the basis of the double-folding model by employing two versions of nucleon–nucleon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Gontchar, I. I. [Omsk State Transport University (Russian Federation); Chushnyakova, M. V., E-mail: maria.chushnyakova@gmail.com [Omsk State Technical University (Russian Federation)

    2016-07-15

    A systematic calculation of barriers for heavy-ion fusion was performed on the basis of the double-folding model by employing two versions of an effective nucleon–nucleon interaction: M3Y interaction and Migdal interaction. The results of calculations by the Hartree–Fockmethod with the SKX coefficients were taken for nuclear densities. The calculations reveal that the fusion barrier is higher in the case of employing theMigdal interaction than in the case of employing the Ðœ3Y interaction. In view of this, the use of the Migdal interaction in describing heavy-ion fusion is questionable.

  8. Excitation of Nucleon Resonances in Heavy-Ion Charge-Exchange Reactions

    Science.gov (United States)

    Benlliure, J.; Vargas, J.; Alvarez-Pol, H.; Aumann, T.; Atkinson, J.; Ayyad, Y.; Beceiro, S.; Borezky, K.; Chatillon, A.; Cortina, D.; Diaz, P.; Estrade, A.; Geissel, H.; Lenske, H.; Litvinov, Y.; Mostazo, M.; Paradela, C.; Pietri, S.; Prochazka, A.; Taieb, J.; Takechi, M.; Vidaña, I.; Weick, H.; Winfield, J.

    Isobaric charge-exchange reactions induced by different tin isotopes have been investigated at GSI. The high-resolving power of the FRS spectrometer made it possible to separate elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic component was associated to the in-medium excitation of nucleon resonances such as the Delta and Roper resonances. These data are expected to contribute to better understand the role of subnuclear degrees of freedom in three body forces or the missing strength in Gamow-Teller transitions but also to investigate the abundance of protons and neutrons at the nuclear periphery.

  9. Dielectron production in heavy ion collisions at 158 GeV/c per nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Busch, Oliver

    2007-12-03

    In this thesis we study dilepton production in Pb-Au collisions at 158 GeV/c per nucleon measured with the Cherenkov Ring Electron Spectrometer (CERES) at the Super Proton Synchrotron (SPS) at CERN. The data taken in the year 2000 represent the first CERES runs with the fully operational Time Projection Chamber (TPC). The upgrade of the spectrometer with this powerful tracking device allows to realize a new approach for particle identification with the Ring Imaging Cherenkov (RICH) detector. We present the development and optimization of track-based ring reconstruction methods which allow to identify both electrons and pions at momenta above the Cherenkov threshold. To compare the performance of different methods, the reconstruction is applied to the CERES data. This allows to determine experimentally, for the first time, the CERES RICH efficiency and background rejection power. The new particle identification is used for low-mass dielectron reconstruction. Significant improvements in the simulation of the detector allow to evaluate the electron pair reconstruction efficiency with high accuracy and to study the origin of electron pair combinatorial background. The results motivate an extension of the TPC tracking, to improve the reconstruction efficiency for low-momentum tracks, and allow better identification of electron background. Our results corroborate the previous CERES findings of an enhancement of electron pairs over the hadronic cocktail in the invariant mass region m{sub inv} >or similar 0.2 GeV/c{sup 2}. Comparison to previous analyses of the same data shows good consistency and supports our estimate of the systematic uncertainties of the electron analysis. Our results supply evidence for a modification of the spectral function of the {rho} meson in the hot and dense medium and strongly support baryon-induced interactions at the origin of the effect. Furthermore, we present in this work the first direct measurements of transition radiation (TR) spectra

  10. LEXUS heavy ion collisions

    CERN Document Server

    Sang Yong Jeon

    1997-01-01

    We use a Glauber-like approach to describe very energetic nucleus- nucleus collisions as a sequence of binary nucleon-nucleon collisions. No free parameters are needed: all the information comes from simple parametrizations of nucleon-nucleon collision data. Produced mesons are assumed not to interact with each other or with the original baryons. Comparisons are made to published experimental measurements of baryon rapidity and transverse momentum distributions, negative hadron rapidity and transverse momentum distributions, average multiplicities of pions, kaons, hyperons, and antihyperons, and zero degree energy distributions for sulfur-sulfur collisions at 200 GeV/c per nucleon and for lead-lead collisions at 158 GeV/c per nucleon. Good agreement is found except that the number of strange particles produced, especially antihyperons, is too small compared with experiment. We call this model LEXUS: Linear EXtrapolation of Ultrarelativistic nucleon-nucleon Scattering to heavy ion collisions. (11 refs).

  11. Heavy-ion transfer reactions at large internuclear distances using the PRISMA magnetic spectrometer

    Directory of Open Access Journals (Sweden)

    Montanari D. J.

    2013-12-01

    Full Text Available We measured excitation functions for the main transfer channels in the 116Sn+60Ni reaction at different bombarding energies from above to well below the Coulomb barrier. The experiment has been performed in inverse kinematics, detecting the lighter (target-like ions with the magnetic spectrometer PRISMA at very forward angles. Good mass, nuclear charge and kinetic energy resolutions have been achieved. The comparison between the data and microscopic calculations for the present case and for the previously measured 96Zr+40Ca system, namely superfluid and near closed shells nuclei, should significantly improve our understanding of nucleon-nucleon correlation properties in multinucleon transfer processes.

  12. $p\\Xi^- $ Correlation in Relativistic Heavy Ion Collisions with Nucleon-Hyperon Interaction from Lattice QCD

    OpenAIRE

    Hatsuda, Tetsuo(Theoretical Research Division, Nishina Center, RIKEN, Saitama 351-0198, Japan); Morita, Kenji; Ohnishi, Akira; Sasaki, Kenji

    2017-01-01

    On the basis of the $p\\Xi^-$ interaction extracted from (2+1)-flavor lattice QCD simulations at the physical point, the momentum correlation of $p$ and $\\Xi^-$ produced in relativistic heavy ion collisions is evaluated. $C_{\\rm SL}(Q)$ defined by a ratio of the momentum correlations between the systems with different source sizes is shown to be largely enhanced at low momentum due to the strong attraction between $p$ and $\\Xi^-$ in the $I=J=0$ channel. Thus, measuring this ratio at RHIC and L...

  13. Multinucleon transfer dynamics in heavy-ion collisions near Coulomb-barrier energies

    Science.gov (United States)

    Niu, Fei; Chen, Peng-Hui; Guo, Ya-Fei; Ma, Chun-Wang; Feng, Zhao-Qing

    2017-12-01

    Multinucleon transfer reactions near barrier energies have been investigated with a multistep model based on the dinuclear system (DNS) concept, in which the capture of two colliding nuclei, the transfer dynamics, and the deexcitation process of primary fragments are described by an analytical formula, diffusion theory, and a statistical model, respectively. The nucleon transfer takes place after forming the DNS and is coupled to the dissipation of relative motion energy and angular momentum by solving a set of microscopically derived master equations within the potential energy surface. Specific reactions of Ca,4840+124Sn , 40Ca(40Ar,58Ni)+232Th , 40Ca(58Ni)+238U , and Ca,4840(58Ni)+248Cm near barrier energies are investigated. It is found that fragments are produced by multinucleon transfer reactions with maximal yields along the β -stability line. The isospin relaxation is particularly significant in the process of fragment formation. The incident energy dependence of heavy target-like fragments in the reaction of 58Ni+248Cm is analyzed thoroughly.

  14. Evaluation of excitation energy and spin from light charged particles multiplicities in heavy-ion collisions

    CERN Document Server

    Steckmeyer, J C; Grotowski, K; Pawowski, P; Aiello, S; Anzalone, A; Bini, M; Borderie, B; Bougault, R; Cardella, G; Casini, G; Cavallaro, S; Charvet, J L; Dayras, R; De Filippo, E; Durand, D; Femin, S; Frankland, J D; Galíchet, E; Geraci, M; Giustolisi, F; Guazzoni, P; Iacono-Manno, M; Lanzalone, G; Lanzan, G; Le Neindre, N; Lo Nigro, S; Lo Piano, F; Olmi, A; Pagano, A; Papa, M; Pârlog, M; Pasquali, G; Piantelli, S; Pirrone, S; Politi, G; Porto, F; Rivet, M F; Rizzo, F; Rosato, E; Roy, R; Sambataro, S; Sperduto, M L; Stefanini, A A; Sutera, C; Tamain, B; Vient, E; Volant, C; Wieleczko, J P; Zetta, L

    2005-01-01

    A simple procedure for evaluating the excitation energy and the spin transfer in heavy-ion dissipative collisions is proposed. It is based on a prediction of the GEMINI evaporation code : for a nucleus with a given excitation energy, the average number of emitted protons decreases with increasing spin, whereas the average number of alpha particles increases. Using that procedure for the reaction 107Ag+58Ni at 52 MeV/nucleon, the excitation energy and spin of quasi-projectiles have been evaluated. The results obtained in this way have been compared with the predictions of a model describing the primary dynamic stage of heavy-ion collisions.

  15. Evolving theoretical descriptions of heavy-ion fusion: from phenomenological to microscopic approaches

    Directory of Open Access Journals (Sweden)

    Hagino K.

    2017-01-01

    Full Text Available We overview the current status of theoretical approaches for heavy-ion fusion reactions at subbarrier energies. We particularly discuss theoretical challenges in the coupled-channels approach, that include i a description of deep subbarrier hindrance of fusion cross sections, ii the role of nuclear dissipation, iii fusion of unstable nuclei, and iv an interplay between fusion and multi-nucleon transfer processes. We also present results of a semi-microscopic approach to heavy-ion fusion reactions, that combines the coupled-channels approach with state-of-the-art microscopic nuclear structure calculations.

  16. Ultrarelativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, H.G.

    1980-12-01

    Studies with ultrarelativistic heavy ions combine aspects of cosmic ray physics, particle physics, nuclear physics, astrophysics and cosmogenesis. The leading theoretical concerns are the behavior of matter at very high-energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and quantum chromodynamics. The field has developed over a period of more than thirty years, since the first observation of heavy nuclei in cosmic rays and the major developments of understanding of high-energy collisions made by Fermi and Landau in the early fifties. In the late sixties the discovery of the parton content of nucleons was rapidly followed by a great extension of high-energy collision phenomenology at the CERN ISR and subsequent confirmation of the QCD theory. In parallel the study of p-nucleus and nucleus-nucleus collisions at very high energies, especially at the CERN PS, Fermilab and the Bevalac, and in cosmic rays demonstrated that studies involving the nucleus opened up a new dimension in studies of the hadronic interaction. It is now at a high level of interest on an international scale, with major new accelerators being proposed to dedicate to this kind of study.

  17. Enhanced nucleon transfer in tip collisions of 238U+124Sn

    Science.gov (United States)

    Sekizawa, Kazuyuki

    2017-10-01

    Multinucleon transfer processes in low-energy heavy ion reactions have attracted increasing interest in recent years aiming at the production of new neutron-rich isotopes. Clearly, it is an imperative task to further develop understanding of underlying reaction mechanisms to lead experiments to success. In this paper, from systematic time-dependent Hartree-Fock calculations for the 238U+124Sn reaction, it is demonstrated that transfer dynamics depend strongly on the orientations of 238U, quantum shells, and collision energies. Two important conclusions are obtained: (i) Experimentally observed many-proton transfer from 238U to 124Sn can be explained by a multinucleon transfer mechanism governed by enhanced neck evolution in tip collisions; (ii) novel reaction dynamics are observed in tip collisions at energies substantially above the Coulomb barrier, where a number of nucleons are transferred from 124Sn to 238U, producing transuranium nuclei as primary reaction products, which could be a means to synthesize superheavy nuclei. Both results indicate the importance of the neck (shape) evolution dynamics, which are sensitive to orientations, shell effects, and collision energies, for exploring possible pathways to produce new unstable nuclei.

  18. Few-body semiclassical approach to nucleon transfer and emission reactions

    Science.gov (United States)

    Sultanov, Renat A.; Guster, D.

    2014-04-01

    A three-body semiclassical model is proposed to describe the nucleon transfer and emission reactions in a heavy-ion collision. In this model the two heavy particles, i.e. nuclear cores A1(ZA1, MA1) and A2(ZA2, MA2), move along classical trajectories {{R}_1}( t ) and {{R}_2}( t ) respectively, while the dynamics of the lighter neutron (n) is considered from a quantum mechanical point of view. Here, Mi are the nucleon masses and Zi are the Coulomb charges of the heavy nuclei (i = 1, 2). A Faddeev-type semiclassical formulation using realistic paired nuclear-nuclear potentials is applied so that all three channels (elastic, rearrangement and break-up) are described in a unified manner. In order to solve the time-dependent equations the Faddeev components of the total three-body wave-function are expanded in terms of the input and output channel target eigenfunctions. In the special case, when the nuclear cores are identical (A1 ≡ A2) and also the two-level approximation in the expansion over the target (subsystem) functions is used, the time-dependent semiclassical Faddeev equations are resolved in an explicit way. To determine the realistic {{R}_1}( t ) and {{R}_2}( t ) trajectories of the nuclear cores, a self-consistent approach based on the Feynman path integral theory is applied.

  19. Bremsstrahlung from relativistic heavy ions in matter

    DEFF Research Database (Denmark)

    Sørensen, Allan Hvidkjær

    2010-01-01

    The emission of electromagnetic radiation by relativistic bare heavy ions penetrating ordinary matter is investigated. Our main aim is to determine the bremsstrahlung which we define as the radiation emitted when the projectile does not break up. It pertains to collisions without nuclear contact....... As a result of its relative softness, bremsstrahlung never dominates the energy-loss process for heavy ions. As to the emission of electromagnetic radiation in collisions with nuclear break-up, it appears modest when pertaining to incoherent action of the projectile nucleons in noncontact collisions...

  20. Radiochemical study of the reactions of heavy ions with gold

    Energy Technology Data Exchange (ETDEWEB)

    Binder, I.

    1977-07-01

    Thick gold foils have been bombarded with heavy-ion projectiles at energies above the Coulomb barrier. The radioactive products were identified and their yields measured using gamma-ray spectrometry and an extensive series of computer programs developed for the data analysis. The total mass-yield distribution was extracted from the data using charge-dispersion curves inferred from the experimental results. One observes a change in the mass-yield distributions corresponding to primarily fusion-fission tractions occurring with the lighter projectiles Ne-20 and Ar-40 and deep-inelastic transfer reactions predominating with heavier Kr-84, Kr-86, and Xe-136 projectiles. For the deep-inelastic transfer reaction, more mass transfer is seen to occur for a higher incident projectile energy, and the Gaussian distribution of products shows exponential tailing. The preferred direction for mass transfer is from gold to the projectile nucleus. Sequential fission is a likely fate for nucludes beyond the lead shell closure. The ''gold finger'' is explained as a combination of mass transfer, nucleon evaporation and sequential fission. The yields of gold nuclides indicate a superposition of two reaction mechanisms, quasi-elastic and deep-inelastic. The angular momentum involved with each mechanism determines which of two isomeric states is the end product of the nuclear reaction. Suggestions are offered regarding the possibility of synthesizing super-heavy elements by use of heavy-ion nuclear reactions.

  1. Coherent diffractive photoproduction of ρ0 mesons on gold nuclei at 200 GeV/nucleon-pair at the Relativistic Heavy Ion Collider

    Science.gov (United States)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Ajitanand, N. N.; Alekseev, I.; Anderson, D. M.; Aoyama, R.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Ashraf, M. U.; Attri, A.; Averichev, G. S.; Bai, X.; Bairathi, V.; Behera, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandenburg, J. D.; Brandin, A. V.; Brown, D.; Bunzarov, I.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chankova-Bunzarova, N.; Chatterjee, A.; Chattopadhyay, S.; Chen, X.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Contin, G.; Crawford, H. J.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elsey, N.; Engelage, J.; Eppley, G.; Esha, R.; Esumi, S.; Evdokimov, O.; Ewigleben, J.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Federicova, P.; Fedorisin, J.; Feng, Z.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A. I.; Hamed, A.; Harlenderova, A.; Harris, J. W.; He, L.; Heppelmann, S.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Horvat, S.; Huang, T.; Huang, B.; Huang, X.; Huang, H. Z.; Humanic, T. J.; Huo, P.; Igo, G.; Jacobs, W. W.; Jentsch, A.; Jia, J.; Jiang, K.; Jowzaee, S.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z.; Kikoła, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Kochenda, L.; Kocmanek, M.; Kollegger, T.; Kosarzewski, L. K.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulathunga, N.; Kumar, L.; Kvapil, J.; Kwasizur, J. H.; Lacey, R.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, X.; Li, C.; Li, W.; Li, Y.; Lidrych, J.; Lin, T.; Lisa, M. A.; Liu, H.; Liu, P.; Liu, Y.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, S.; Luo, X.; Ma, G. L.; Ma, L.; Ma, Y. G.; Ma, R.; Magdy, N.; Majka, R.; Mallick, D.; Margetis, S.; Markert, C.; Matis, H. S.; Meehan, K.; Mei, J. C.; Miller, Z. W.; Minaev, N. G.; Mioduszewski, S.; Mishra, D.; Mizuno, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nie, M.; Nigmatkulov, G.; Niida, T.; Nogach, L. V.; Nonaka, T.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V. A.; Olvitt, D.; Page, B. S.; Pak, R.; Pandit, Y.; Panebratsev, Y.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Pluta, J.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Ray, R. L.; Reed, R.; Rehbein, M. J.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roth, J. D.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Salur, S.; Sandweiss, J.; Saur, M.; Schambach, J.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Schweid, B. R.; Seger, J.; Sergeeva, M.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, A.; Sharma, M. K.; Shen, W. Q.; Shi, Z.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Singha, S.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solyst, W.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Strikhanov, M.; Stringfellow, B.; Sugiura, T.; Sumbera, M.; Summa, B.; Sun, Y.; Sun, X. M.; Sun, X.; Surrow, B.; Svirida, D. N.; Tang, A. H.; Tang, Z.; Taranenko, A.; Tarnowsky, T.; Tawfik, A.; Thäder, J.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Todoroki, T.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vasiliev, A. N.; Videbæk, F.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, G.; Wang, Y.; Wang, F.; Wang, Y.; Webb, J. C.; Webb, G.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y.; Xiao, Z. G.; Xie, W.; Xie, G.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y. F.; Xu, Z.; Yang, Y.; Yang, Q.; Yang, C.; Yang, S.; Ye, Z.; Ye, Z.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, Z.; Zhang, X. P.; Zhang, J. B.; Zhang, S.; Zhang, J.; Zhang, Y.; Zhang, J.; Zhang, S.; Zhao, J.; Zhong, C.; Zhou, L.; Zhou, C.; Zhu, X.; Zhu, Z.; Zyzak, M.; STAR Collaboration

    2017-11-01

    The STAR Collaboration reports on the photoproduction of π+π- pairs in gold-gold collisions at a center-of-mass energy of 200 GeV/nucleon-pair. These pion pairs are produced when a nearly real photon emitted by one ion scatters from the other ion. We fit the π+π- invariant-mass spectrum with a combination of ρ0 and ω resonances and a direct π+π- continuum. This is the first observation of the ω in ultraperipheral collisions, and the first measurement of ρ -ω interference at energies where photoproduction is dominated by Pomeron exchange. The ω amplitude is consistent with the measured γ p →ω p cross section, a classical Glauber calculation, and the ω →π+π- branching ratio. The ω phase angle is similar to that observed at much lower energies, showing that the ρ -ω phase difference does not depend significantly on photon energy. The ρ0 differential cross section d σ /d t exhibits a clear diffraction pattern, compatible with scattering from a gold nucleus, with two minima visible. The positions of the diffractive minima agree better with the predictions of a quantum Glauber calculation that does not include nuclear shadowing than with a calculation that does include shadowing.

  2. Heavy Ion Physics at CMS

    CERN Document Server

    Veres, Gabor

    2017-01-01

    In the present proceedings recent heavy ion results from the Compact Muon Solenoid collaboration at the LHC are presented. These contain comparisons between small and large collision systems, as well as studies of energy evolution, thus include data collected in proton-proton collisions at 13 TeV (2015 and 2016), proton-proton and lead-lead collisions at 5 TeV (2015), and proton-lead collisions at 5 TeV and 8 TeV (2016) center-of-mass energy per nucleon pair. They provide new insights into the properties of the extremely high density and high temperature matter created in heavy ion collisions, while pointing out similarities and differences in comparison to smaller collision systems. These include gluon distribution functions in the lead nucleus; the azimuthal anisotropy of final state particle distributions in all the three different collision systems; charge separation signals from proton-lead collisions and consequences for the Chiral Magnetic Effect; new studies of parton energy loss and its dependence on...

  3. Transfer products from the reactions of heavy ions with heavy nuclei. [394 to 1156 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, K.E. III

    1979-11-01

    Production of nuclides heavier than the target from /sup 86/Kr- and /sup 136/Xe-induced reactions with /sup 181/Ta and /sup 238/U was investigated. Attempts were made to produce new neutron-excess Np and Pu isotopes by the deep inelastic mechanism. No evidence was found for /sup 242/Np or /sup 247/Pu. Estimates were made for the production of /sup 242/Np, /sup 247/Pu, and /sup 248/Am from heavy-ion reactions with uranium targets. Comparisons of reactions of /sup 86/Kr and /sup 136/Xe ions with thick /sup 181/Ta targets and /sup 86/Kr, /sup 136/Xe and /sup 238/U ions with thick /sup 238/U targets indicate that the most probable products are not dependent on the projectile. The most probable products can be predicted by the equation Z - Z/sub target/ = 0.43 (A - A/sub target/) + 1.0. The major effect of the projectile is the magnitude of the production cross section of the heavy products. Based on these results, estimates are made of the most probable mass of element 114 produced from heavy-ion reactions with /sup 248/Cm and /sup 254/Es targets. These estimates give the mass number of element 114 as approx. 287 if produced in heavy-ion reactions with these very heavy targets. Excitation functions of gold and bismuth isotopes arising from /sup 86/Kr- and /sup 136/Xe-induced reactions with thin /sup 181/Ta targets were measured. These results indicate that the shape and location (in Z and A above the target) of the isotopic distributions are not strongly dependent on the projectile incident energy. Also, the nuclidic cross sections are found to increase with an increase in projectile energy to a maximum at approximately 1.4 to 1.5 times the Coulomb barrier. Above this maximum, the nuclidic cross sections are found to decrease with an increase in projectile energy. This decrease in cross section is believed to be due to fission of the heavy products caused by high excitation energy and angular momentum. 111 references, 39 figures, 34 tables.

  4. Polarization transfer in weak pion production off the nucleon

    Science.gov (United States)

    Graczyk, Krzysztof M.; Kowal, Beata E.

    2018-01-01

    Polarization transfer (PT) observables in the single pion production induced by the charged current interaction of the neutrino with the nucleon are examined. The polarization components of the final nucleon and the charged lepton are calculated within two models for the pion production. The predictions are made for neutrino energy of the order of 1 GeV as well as for the T2K energy distribution. It is demonstrated that the PT observables, the degree of polarization and the polarization components of outgoing fermions, are sensitive to assumptions about the nonresonant background model. In particular it is shown that the normal components of the polarization of the outgoing nucleon and the lepton are determined by the interference between the resonant (RES) and nonresonant (NB) amplitudes. Moreover, the sign of the normal component of the polarization of the charged lepton is fixed by the relative sign between the RES and the NB amplitudes.

  5. Few-body semiclassical approach to nucleon transfer and emission reactions

    Directory of Open Access Journals (Sweden)

    Sultanov Renat A.

    2014-04-01

    Full Text Available A three-body semiclassical model is proposed to describe the nucleon transfer and emission reactions in a heavy-ion collision. In this model the two heavy particles, i.e. nuclear cores A1(ZA1, MA1 and A2(ZA2, MA2, move along classical trajectories R→1(t${{\\vec R}_1}\\left( t \\right$ and R→2(t${{\\vec R}_2}\\left( t \\right$ respectively, while the dynamics of the lighter neutron (n is considered from a quantum mechanical point of view. Here, Mi are the nucleon masses and Zi are the Coulomb charges of the heavy nuclei (i = 1, 2. A Faddeev-type semiclassical formulation using realistic paired nuclear-nuclear potentials is applied so that all three channels (elastic, rearrangement and break-up are described in a unified manner. In order to solve the time-dependent equations the Faddeev components of the total three-body wave-function are expanded in terms of the input and output channel target eigenfunctions. In the special case, when the nuclear cores are identical (A1 ≡ A2 and also the two-level approximation in the expansion over the target (subsystem functions is used, the time-dependent semiclassical Faddeev equations are resolved in an explicit way. To determine the realistic R→1(t${{\\vec R}_1}\\left( t \\right$ and R→2(t${{\\vec R}_2}\\left( t \\right$ trajectories of the nuclear cores, a self-consistent approach based on the Feynman path integral theory is applied.

  6. The time-of-flight spectrometer for heavy ions PISOLO

    Energy Technology Data Exchange (ETDEWEB)

    Montagnoli, G. E-mail: montagnoli@pd.infn.it; Scarlassara, F.; Beghini, S.; Dal Bello, A.; Segato, G.F.; Stefanini, A.M.; Ackermann, D.; Corradi, L.; He, J.H.; Lin, C.J

    2000-11-11

    A time-of-flight spectrometer with magnetic focusing has been installed at the Laboratori Nazionali di Legnaro. The spectrometer's length is 3.6 m and allows for high-resolution time-of-flight measurements. Magnetic focusing is accomplished by two quadrupole doublets. The spectrometer is connected to a sliding seal scattering chamber rotating over a large angular range. Micro channel-plate detectors for start/stop signals and an ionization chamber for {delta}E-E measurements at the focal plane, are used. The setup provides a maximum effective solid angle {delta}{omega}=2.8 msr, and is dedicated to the study of quasi-elastic reactions between heavy ions; in particular, it has already been used to investigate near-barrier multi-nucleon transfer processes.

  7. arXiv Heavy ions at the Future Circular Collider

    CERN Document Server

    Dainese, A.; Armesto, N.; d'Enterria, D.; Jowett, J.M.; Lansberg, J.P.; Milhano, J.G.; Salgado, C.A.; Schaumann, M.; van Leeuwen, M.; Albacete, J.L.; Andronic, A.; Antonioli, P.; Apolinario, L.; Bass, S.; Beraudo, A.; Bilandzic, A.; Borsanyi, S.; Braun-Munzinger, P.; Chen, Z.; Cunqueiro Mendez, L.; Denicol, G.S.; Eskola, K.J.; Floerchinger, S.; Fujii, H.; Giubellino, P.; Greiner, C.; Grosse-Oetringhaus, J.F.; Ko, C.M.; Kotko, P.; Krajczar, K.; Kutak, K.; Laine, M.; Liu, Y.; Lombardo, M.P.; Luzum, M.; Marquet, C.; Masciocchi, S.; Okorokov, V.; Paquet, J.F.; Paukkunen, H.; Petreska, E.; Pierog, T.; Ploskon, M.; Ratti, C.; Rezaeian, A.H.; Riegler, W.; Rojo, J.; Roland, C.; Rossi, A.; Salam, G.P.; Sapeta, S.; Schicker, R.; Schmidt, C.; Stachel, J.; Uphoff, J.; van Hameren, A.; Watanabe, K.; Xiao, B.W.; Yuan, F.; Zaslavsky, D.; Zhou, K.; Zhuang, P.

    2017-06-22

    The Future Circular Collider (FCC) Study is aimed at assessing the physics potential and the technical feasibility of a new collider with centre-of-mass energies, in the hadron-hadron collision mode, seven times larger than the nominal LHC energies. Operating such machine with heavy ions is an option that is being considered in the accelerator design studies. It would provide, for example, Pb-Pb and p-Pb collisions at sqrt{s_NN} = 39 and 63 TeV, respectively, per nucleon-nucleon collision, with integrated luminosities above 30 nb^-1 per month for Pb-Pb. This is a report by the working group on heavy-ion physics of the FCC Study. First ideas on the physics opportunities with heavy ions at the FCC are presented, covering the physics of the Quark-Gluon Plasma, of gluon saturation, of photon-induced collisions, as well as connections with other fields of high-energy physics.

  8. Excited states populated via nucleon transfer in the reaction [sup 32]S+[sup 208]Pb

    Energy Technology Data Exchange (ETDEWEB)

    Corradi, L.; Petrache, C.M.; Ackermann, D.; De Angelis, G.; Moreno, H.; Napoli, D.R.; Spolaore, P.; Stefanini, A.M. (INFN, Lab. Nazionali di Legnaro (Italy)); Beghini, S.; Montagnoli, G.; Scarlassara, F.; Segato, G.F.; Signorini, C. (Padua Univ. (Italy). Dipt. di Fisica INFN, Padua (Italy)); Pollarolo, G. (Turin Univ. (Italy). Dipt. di Fisica INFN, Turin (Italy))

    1993-01-01

    The population strengths of excited states in nuclei produced via transfer reactions in the 185 MeV[sup 32]S+[sup 208]Pb reaction have been investigated by heavy-ion-[gamma] coincidence techniques. The cross sections extracted from the [gamma] spectra, have been analyzed in the framework of the Complex WKB approximation theory. (orig.).

  9. Relativistic heavy ions physics

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, B.

    1989-01-01

    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.,

  10. Model for Cumulative Solar Heavy Ion Energy and LET Spectra

    Science.gov (United States)

    Xapsos, Mike; Barth, Janet; Stauffer, Craig; Jordan, Tom; Mewaldt, Richard

    2007-01-01

    A probabilistic model of cumulative solar heavy ion energy and lineary energy transfer (LET) spectra is developed for spacecraft design applications. Spectra are given as a function of confidence level, mission time period during solar maximum and shielding thickness. It is shown that long-term solar heavy ion fluxes exceed galactic cosmic ray fluxes during solar maximum for shielding levels of interest. Cumulative solar heavy ion fluences should therefore be accounted for in single event effects rate calculations and in the planning of space missions.

  11. Elucidating Jet Energy Loss in Heavy Ion Collisions

    CERN Document Server

    Grau, N

    2008-01-01

    Very soon the LHC will provide beams for heavy ion collisions at 5.52 TeV/nucleon. This center-of-mass energy results in a large cross-section for producing high-$E_T$ ($>$ 50 GeV) jets that are distinct from the soft, underlying event. This brings with it the possibility of performing full jet reconstruction to directly study jet energy loss in the medium produced in heavy ion collisions. In this note, we present the current state of jet reconstruction performance studies in heavy ion events using the ATLAS detector. We also discuss the possibilities of energy loss measurements available with full jet reconstruction: single jet $R_{AA}$ and di-jet and $\\gamma$-jet correlations.

  12. The future of heavy ion radiotherapy.

    Science.gov (United States)

    Jäkel, Oliver; Karger, Christian P; Debus, Jürgen

    2008-12-01

    Currently, there is an increasing interest in heavy ion radiotherapy (RT) and a number of new facilities are being installed in Europe and Japan. This development is accompanied by intensive technical, physical, and clinical research. The authors identify six research fields where progress is likely and propose a thesis on the expected achievements for each of the fields: (1) Synchrotrons with active energy variation and three-dimensional beam scanning will be the standard in ion beam RT. (2) Common standards for precise measurement, prescription, and reporting of dose will be available. (3) Intensity-modulated particle therapy will be state-of-the-art. (4) Time-adaptive treatments of moving targets will be feasible. (5) Therapeutic effectiveness of heavy ions will be known for the most important indications while cost effectiveness will remain to be shown. (6) The potential of high-linear energy transfer radiation will be known. The rationale for each of these theses is described.

  13. Current experimental situation in heavy-ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D.K.

    1978-06-01

    A detailed survey of the present experimental situation in heavy-ion physics is presented. The discussion begins by considering the simple excitation of discrete states in elastic scattering, transfer, and compound-nucleus reactions; it then turns to more drastic perturbations of the nucleus high in the continuum through fusion, fission, and deeply inelastic scattering, and concludes with the (possibly) limiting asymptotic phenomena of relativistic heavy-ion collisions. 138 figures, 5 tables, 451 references. (RWR)

  14. Constructing Nucleon Operators on a Lattice for Form Factors with High Momentum Transfer

    Energy Technology Data Exchange (ETDEWEB)

    Syritsyn, Sergey [Stony Brook Univ., NY (United States); Gambhir, Arjun S. [College of William and Mary, Williamsburg, VA (United States); Musch, Bernhard U. [Univ. of Regensburg (Germany); Orginos, Konstantinos [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2017-05-01

    We present preliminary results of computing nucleon form factor at high momentum transfer using the 'boosted' or 'momentum' smearing. We use gauge configurations generated with N f = 2 + 1dynamical Wilson-clover fermions and study the connected as well as disconnected contributions to the nucleon form factors. Our initial results indicate that boosted smearing helps to improve the signal for nucleon correlators at high momentum. However, we also find evidence for large excited state contributions, which will likely require variational analysis to isolate the boosted nucleon ground state.

  15. Thermodynamic interpretation of multiparticle emission in relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Gleeson, A.M.; Raha, S.

    1980-02-01

    The scattering of the heavy ion Ne from NaF is analyzed at relativistic energy. The spectra of the emission fragments are studied for evidence of a thermodynamic-hydrodynamic collective motion. The spectra of pion, deuteron, and proton emission are fitted for fixed beam and target. The fit is consistent with an interpretation of an expanding hot fluid of interacting nucleons. 2 figures.

  16. Heavy ion fusion--Using heavy ions to make electricity

    Energy Technology Data Exchange (ETDEWEB)

    Celata, C.M.

    2004-03-15

    The idea of using nuclear fusion as a source of commercial electrical power has been pursued worldwide since the 1950s. Two approaches, using magnetic and inertial confinement of the reactants, are under study. This paper describes the difference between the two approaches, and discusses in more detail the heavy-ion-driven inertial fusion concept. A multibeam induction linear accelerator would be used to bring {approx}100 heavy ion beams to a few GeV. The beams would then heat and compress a target of solid D-T. This approach is unique among fusion concepts in its ability to protect the reaction chamber wall from neutrons and debris.

  17. Heavy-ion nucleus scattering

    CERN Document Server

    Rahman, M A; Haque, S

    2003-01-01

    Heavy ion-nucleus scattering is an excellent laboratory to probe high spin phenomena, exotic nuclei and for the analysis of various exit channels. The Strong Absorption Model or the generalized diffraction models, which are semi-classical in nature, have been employed in the description of various heavy ion-nucleus scattering phenomena with reasonable success. But one needs to treat the deflection function (scattering angles) quantum mechanically in the Wave Mechanical picture for the appropriate description of the heavy-ion nucleus scattering phenomena. We have brought the mathematics for the cross-section of the heavy-ion nucleus scattering to an analytic expression taking account of the deflection function (scattering angles) quantum mechanically. sup 9 Be, sup 1 sup 6 O, sup 2 sup 0 Ne and sup 3 sup 2 S heavy-ion beams elastic scattering from sup 2 sup 8 Si, sup 2 sup 4 Mg and sup 4 sup 0 Ca target nuclei at various projectile energies over the range 20-151 MeV have been analysed in terms of the 2-paramet...

  18. Results of heavy ion radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.R. [Lawrence Berkeley Lab., CA (United States). Life Sciences Div.

    1994-04-01

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists.

  19. Heavy ions: Report from Relativistic Heavy Ion Collider

    Indian Academy of Sciences (India)

    We review selected highlights from the experiments at the Relativistic Heavy Ion Collider (RHIC) exploring the QCD phase diagram. A wealth of new results appeared recently from RHIC due to major recent upgrades, like for example the Υ suppression in central nucleus-nucleus collisions which has been discovered ...

  20. Pre-equilibrium (exciton) model and the heavy-ion reactions with cluster emission

    CERN Document Server

    Betak, E

    2015-01-01

    We bring the possibility to include the cluster emission into the statistical pre-equilibrium (exciton) model enlarged for considering also the heavy ion collisions. At this moment, the calculations have been done without treatment of angular momentum variables, but all the approach can be straightforwardly applied to heavy-ion reactions with cluster emission including the angular momentum variables. The direct motivation of this paper is a possibility of producing the superdeformed nuclei, which are easier to be detected in heavy-ion reactions than in those induced by light projectiles (nucleons, deuterons, $\\alpha$-particles).

  1. Future relativistic heavy ion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, H.G.

    1980-12-01

    Equations of state for nuclear matter and ongoing experimental studies are discussed. Relativistic heavy ion physics is the only opportunity to study in the laboratory the properties of extended multiquark systems under conditions such that quarks might run together into new arrangements previously unobserved. Several lines of further study are mentioned. (GHT)

  2. Semiholography for heavy ion collisions

    CERN Document Server

    Mukhopadhyay, Ayan

    2017-01-01

    The formation of QGP in heavy ion collisions gives us a great opportunity for learning about nonperturbative dynamics of QCD. Semiholography provides a new consistent framework to combine perturbative and non-perturbative effects in a coherent way and can be applied to obtain an effective description for heavy ion collisions. In particular, it allows us to include nonperturbative effects in existing glasma effective theory and QCD kinetic theory for the weakly coupled saturated degrees of freedom liberated by the collisions in the initial stages in a consistent manner. We argue why the full framework should be able to confront experiments with only a few phenomenological parameters and present feasibility tests for the necessary numerical computations. Furthermore, we discuss that semiholography leads to a new description of collective flow in the form of a generalised non-Newtonian fluid. We discuss some open questions which we hope to answer in the near future.

  3. Holifield Heavy Ion Research Facility

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.; Alton, G.D.; Ball, J.B.; Biggerstaff, J.A.; Dowling, D.T.; Erb, K.A.; Haynes, D.L.; Hoglund, D.E.; Hudson, E.D.; Juras, R.C.

    1986-02-15

    The Holifield Heavy Ion Research Facility has been in routine operation since July 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we discuss our operational experience and recent development activities.

  4. Holifield Heavy Ion Research Facility

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.; Alton, G.D.; Ball, J.B.; Biggerstaff, J.A.; Dowling, D.T.; Erb, K.A.; Haynes, D.L.; Hoglund, D.E.; Hudson, E.D.; Juras, R.C.

    1985-01-01

    The Holifield Heavy Ion Research Facility has been in routine operation since July 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we discuss our operational experience and recent development activities.

  5. Heavy-ion Physics (ATLAS)

    CERN Document Server

    Przybycien, Mariusz; The ATLAS collaboration

    2017-01-01

    The ATLAS experiment at the Large Hadron Collider has undertaken a broad physics program to probe and characterize the hot nuclear matter created in relativistic heavy-ion collisions. This talk presents recent results on production of electroweak bosons and quarkonium, charged particles and jets, bulk particle collectivity and electromagnetic processes in ultra-peripheral collisions, from Pb+Pb and p+Pb collisions.

  6. Heavy ion therapy: Bevalac epoch

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.R.

    1993-10-01

    An overview of heavy ion therapy at the Bevelac complex (SuperHILac linear accelerator + Bevatron) is given. Treatment planning, clinical results with helium ions on the skull base and uveal melanoma, clinical results with high-LET charged particles, neon radiotherapy of prostate cancer, heavy charged particle irradiation for unfavorable soft tissue sarcoma, preliminary results in heavy charged particle irradiation of bone sarcoma, and irradiation of bile duct carcinoma with charged particles and-or photons are all covered. (GHH)

  7. Heavy-ion performance of the LHC and future colliders

    Energy Technology Data Exchange (ETDEWEB)

    Schaumann, Michaela

    2015-04-29

    In 2008 the Large Hadron Collider (LHC) and its experiments started operation at the European Centre of Nuclear Research (CERN) in Geneva with the main aim of finding or excluding the Higgs boson. Only four years later, on the 4th of July 2012, the discovery of a Higgs-like particle was proven and first published by the two main experiments ATLAS and CMS. Even though proton-proton collisions are the main operation mode of the LHC, it also acts as an heavy-ion collider. Here, the term ''heavy-ion collisions'' refers to the collision between fully stripped nuclei. While the major hardware system of the LHC is compatible with heavy-ion operation, the beam dynamics and performance limits of ion beams are quite different from those of protons. Because of the higher mass and charge of the ions, beam dynamic effects like intra-beam scattering and radiation damping are stronger. Also the electromagnetic cross-sections in the collisions are larger, leading to significantly faster intensity decay and thus shorter luminosity lifetimes. As the production cross-sections for various physics processes under study of the experiments are still small at energies reachable with the LHC and because the heavy-ion run time is limited to a few days per year, it is essential to obtain the highest possible collision rate, i.e. maximise the instantaneous luminosity, in order to obtain enough events and therefore low statistical errors. Within this thesis, the past performance of the LHC in lead-lead (Pb-Pb) collisions, at a centre-of-mass energy of 2.76 TeV per colliding nucleon pair, is analysed and potential luminosity limitations are identified. Tools are developed to predict future performance and techniques are presented to further increase the luminosity. Finally, a perspective on the future of high energy heavy-ion colliders is given.

  8. Vector mesons in dense matter and dilepton production in heavy ion collisions at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Santini, Elvira

    2008-02-15

    The vector meson spectral functions are calculated to the first order in the nuclear matter density assuming the dominant contribution comes from the couplings of the vector mesons to nucleons and nucleon resonances. An attempt is made to reproduce the HADES dilepton production data with the in-medium spectral functions of the vector mesons using the Relativistic Quantum Molecular Dynamics (RQMD) transport model developed earlier for modelling heavy-ion collisions. The results are sensitive to the in-medium broadening of nucleon resonances. A generally good agreement with the HADES data is achieved for selfconsistent treatment of the nucleon resonance broadening and the vector meson spectral functions. (orig.)

  9. Measurements of secondary neutrons producted from thick targets bombarded by heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Kurosawa, T.; Nakamura, T. [Tohoku Univ., Sendai (Japan). Cyclotron and Radioisotope Center; Nakao, N.; Shibata, T.; Uwamino, Y.; Nakanishi, N.; Fukumura, A.; Kumamoto, Y.

    1997-03-01

    We measured neutron angular and energy distributions from high energy heavy ions stopping in targets of carbon, aluminum, copper and lead at HIMAC. These spectra are much harder for the lighter target nucleus like carbon. This means that the momentum transfer in the forward direction from heavy ion beam to lighter nuclei is much higher than that to heavier nuclei. (author)

  10. Strange Particles and Heavy Ion Physics

    Energy Technology Data Exchange (ETDEWEB)

    Bassalleck, Bernd [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Physics and Astronomy; Fields, Douglas [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Physics and Astronomy

    2016-04-28

    This very long-running grant has supported many experiments in nuclear and particle physics by a group from the University of New Mexico. The gamut of these experiments runs from many aspects of Strangeness Nuclear Physics, to rare Kaon decays, to searches for exotic Hadrons such as Pentaquark or H-Dibaryon, and finally to Spin Physics within the PHENIX collaboration at RHIC. These experiments were performed at a number of laboratories worldwide: first and foremost at Brookhaven National Lab (BNL), but also at CERN, KEK, and most recently at J-PARC. In this Final Technical Report we summarize progress and achievements for this award since our last Progress Report, i.e. for the period of fall 2013 until the award’s termination on November 30, 2015. The report consists of two parts, representing our two most recent experimental efforts, participation in the Nucleon Spin Physics program of the PHENIX experiment at RHIC, the Relativistic Heavy Ion Collider at BNL – Task 1, led by Douglas Fields; and participation in several Strangeness Nuclear Physics experiments at J-PARC, the Japan Proton Accelerator Research Center in Tokai-mura, Japan – Task 2, led by Bernd Bassalleck.

  11. State density formalism of the Iwamoto-Harada model: A suitable tool to treat cluster emission from heavy-ion collisions with account for spin variables

    Directory of Open Access Journals (Sweden)

    Běták Emil

    2017-01-01

    Full Text Available We study the possibility to include the cluster emission into the statistical pre-equilibrium (exciton model suitable also for heavy ion collisions. The direct motivation of this paper is a possibility of producing superdeformed nuclei, which are easier to be detected in heavy-ion reactions than in those induced by light projectiles (nucleons, deuterons, α-particles.

  12. Microchannel plate based detector for a heavy ion beam spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.I.

    1979-10-01

    The design parameters and operating characteristics of the detector used in the Brutus and Fannie heavy ion beam spectrometers at the SuperHILAC facility are described. The detector utilizes a 25 mm diameter microchannel plate array to obtain gains of 10/sup 2/ to 10/sup 8/ with a linear dynamic range of 10/sup 3/. It has had over three years of almost maintenance-free service, detecting ion beams from carbon to xenon with energies between 1.2 and 8.5 MeV per nucleon.

  13. Chromosome Aberrations by Heavy Ions

    Science.gov (United States)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  14. Results from the first heavy ion run at the LHC

    CERN Document Server

    Schukraft, J

    2012-01-01

    Early November 2010, the LHC collided for the first time heavy ions, Pb on Pb, at a centre-of-mass energy of 2.76 TeV/nucleon. This date marked both the end of almost 20 years of preparing for nuclear collisions at the LHC, as well as the start of a new era in ultra-relativistic heavy ion physics at energies exceeding previous machines by more than an order of magnitude. This contribution summarizes some of the early results from all three experiments participating in the LHC heavy ion program (ALICE, ATLAS, and CMS), which show that the high density matter created at the LHC, while much hotter and larger, still behaves like the very strongly interacting, almost perfect liquid discovered at RHIC. Some surprising and even puzzling results are seen in particle ratios, jet-quenching, and Quarkonia suppression observables. The overall experimental conditions at the LHC, together with its set of powerful and state-of-the-art detectors, should allow for precision measurements of quark-gluon-plasma parameters like v...

  15. Results from the first heavy ion run at the LHC

    Science.gov (United States)

    Schukraft, J.

    2012-09-01

    Early November 2010, the LHC collided for the first time heavy ions, Pb on Pb, at a centre-of-mass energy of 2.76 TeV/nucleon. This date marked both the end of almost 20 years of preparing for nuclear collisions at the LHC, as well as the start of a new era in ultra-relativistic heavy ion physics at energies exceeding previous machines by more than an order of magnitude. This contribution summarizes some of the early results from all three experiments participating in the LHC heavy ion program (ALICE, ATLAS, and CMS), which show that the high density matter created at the LHC, while much hotter and larger, still behaves like the very strongly interacting, almost perfect liquid discovered at RHIC. Some surprising and even puzzling results are seen in particle ratios, jet-quenching, and Quarkonia suppression observables. The overall experimental conditions at the LHC, together with its set of powerful and state-of-the-art detectors, should allow for precision measurements of quark-gluon-plasma parameters like viscosity and opacity.

  16. From nuclei to nucleons. [10 to 200 MeV/nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D.K.

    1978-03-01

    Some initial experiments in the intermediate energy region between 10 and 200 MeV/nucleon, which is largely unexplored and poorly understood is considered as regards some initial experiments in this energy region. Included are the emission of complex fragments, localization in heavy ion reactions, coincidence experiments between light and heavy fragments, and the emission of light particles in heavy ion collisions. Some initial results in the region between 20 and 100 MeV/nucleon are presented. 41 references. (JFP)

  17. QCD in heavy ion collisions

    CERN Document Server

    Iancu, Edmond

    2014-04-10

    These lectures provide a modern introduction to selected topics in the physics of ultrarelativistic heavy ion collisions which shed light on the fundamental theory of strong interactions, the Quantum Chromodynamics. The emphasis is on the partonic forms of QCD matter which exist in the early and intermediate stages of a collision -- the colour glass condensate, the glasma, and the quark-gluon plasma -- and on the effective theories that are used for their description. These theories provide qualitative and even quantitative insight into a wealth of remarkable phenomena observed in nucleus-nucleus or deuteron-nucleus collisions at RHIC and/or the LHC, like the suppression of particle production and of azimuthal correlations at forward rapidities, the energy and centrality dependence of the multiplicities, the ridge effect, the limiting fragmentation, the jet quenching, or the dijet asymmetry.

  18. Relativistic heavy-ion physics: Experimental overview

    Indian Academy of Sciences (India)

    Abstract. The field of relativistic heavy-ion physics is reviewed with emphasis on new results and highlights from the first run of the relativistic heavy-ion collider at BNL and the 15 year research programme at the super proton synchrotron (SPS) at CERN and the AGS at BNL.

  19. Beam losses in heavy ion drivers

    CERN Document Server

    Mustafin, E R; Hofmann, I; Spiller, P J

    2002-01-01

    While beam loss issues have hardly been considered in detail for heavy ion fusion scenarios, recent heavy ion machine developments in different labs (European Organization for Nuclear Research (CERN), Gesellschaft fur Schwerionenforschung (GSI), Institute for Theoretical and Experimental Physics (ITEP), Relativistic Heavy-Ion Collider (RHIC)) have shown the great importance of beam current limitations due to ion losses. Two aspects of beam losses in heavy ion accelerators are theoretically considered: (1) secondary neutron production due to lost ions, and (2) vacuum pressure instability due to charge exchange losses. Calculations are compared and found to be in good agreement with measured data. The application to a Heavy-Ion Driven Inertial Fusion (HIDIF) scenario is discussed. 12 Refs.

  20. Modeling multi-nucleon transfer in symmetric collisions of massive nuclei

    Directory of Open Access Journals (Sweden)

    T. Welsh

    2017-08-01

    Full Text Available Symmetric collisions of massive nuclei, such as 238U + 248Cm, have been proposed as ways to make new n-rich heavy nuclei via multi-nucleon transfer (MNT reactions. We have measured the yields of several projectile-like and target-like fragments from the reaction of 1360 MeV 204Hg + 198Pt. We find that current models for this symmetric collision (GRAZING, DNS, ImQMD significantly underestimate the yields of these transfer products, even for small transfers.

  1. Modeling multi-nucleon transfer in symmetric collisions of massive nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, T.; Loveland, W.; Yanez, R.; Barrett, J. S.; McCutchan, E. A.; Sonzogni, A. A.; Johnson, T.; Zhu, S.; Greene, J. P.; Ayangeakaa, A. D.; Carpenter, M. P.; Lauritsen, T.; Harker, J. L.; Walters, W. B.; Amro, B. M. S.; Copp, P.

    2017-08-01

    Symmetric collisions of massive nuclei, such as U-238 + Cm-248, have been proposed as ways to make new n-rich heavy nuclei via multi-nucleon transfer (MNT) reactions. We have measured the yields of several projectile-like and target-like fragments from the reaction of 1360 MeV Hg-204 + Pt-198. We find that current models for this symmetric collision (GRAZING, DNS, ImQMD) significantly underestimate the yields of these transfer products, even for small transfers. (C) 2017 The Author(s). Published by Elsevier B.V.

  2. heavy ion acceleration at shocks

    Science.gov (United States)

    Shevchenko, V. I.; Galinsky, V.

    2009-12-01

    The theoretical study of alpha particle acceleration at a quasi-parallel shock due to interaction with Alfven waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model [1]. The model uses conservation laws and resonance conditions to find where waves will be generated or dumped and hence particles will be pitch--angle scattered as well as the change of the wave energy due to instability or damping. It includes in consideration the total distribution function (the bulk plasma and high energy tail), so no any assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles) are required. In previous studies heavy ions were treated as perfect test particles, they only experienced the Alfven turbulence excited by protons and didn’t contribute to turbulence generation. In contrast to this approach, we consider the ion scattering on hydromagnetic turbulence generated by both protons and ions themselves. It is important for alpha particles with their relatively large mass-loading parameter that defines efficiency of the wave excitation by alpha particles. The energy spectra of alpha particles is found and compared with those obtained in test particle approximation. [1] Galinsky, V.L., and V.I. Shevchenko, Astrophys. J., 669, L109, 2007.

  3. Heavy Ion Fusion Accelerator Research (HIFAR)

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C{sub s}+ sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac.

  4. Detector system for the study of low energy heavy ion reactions using kinematic coincidence technique

    Science.gov (United States)

    Jhingan, Akhil; Kalkal, S.; Sugathan, P.; Golda, K. S.; Ahuja, R.; Gehlot, J.; Madhavan, N.; Behera, B. R.; Mandal, S. K.

    2014-05-01

    The characteristics and performance of a new detector system developed for the study of low energy heavy ion binary reactions using the kinematic coincidence technique are presented. The detector system has been developed to carry out experiments such as multi-nucleon transfer reactions using the General Purpose Scattering Chamber (GPSC) facility at IUAC [1,2]. The detector system consists of a pair of two-dimensional position sensitive multi wire proportional counter (MWPC) and a ΔE - E gas ionization chamber. Both MWPC have an active area of 5×5 cm2, and provide position signals in horizontal (X) and vertical (Y) plane, and timing signal for time of flight measurements. The main design feature of MWPC is the reduced wire pitch of 0.025 in. (0.635 mm) in all electrodes, giving uniform field and faster charge collection, and usage of 10 μm diameter in anode frame which gives higher gains. The position resolution of the detectors was determined to be 0.45 mm FWHM and time resolution was estimated to be 400 ps FWHM. The detector could handle heavy ion count rates exceeding 100 kHz without any break down. The timing and position signals of the detectors are used for kinematic coincidence measurements and subsequent extraction of their mass and angular distributions. The ionization chamber has a conventional transverse field geometry with segmented anode providing multiple ΔE signals for nuclear charge (Z) identification. This article describes systematic study of these detectors in terms of efficiency, count rate handling capability, time, position and energy resolution.

  5. Detector system for the study of low energy heavy ion reactions using kinematic coincidence technique

    Energy Technology Data Exchange (ETDEWEB)

    Jhingan, Akhil, E-mail: akhil@iuac.res.in [Inter University Accelerator Centre, P. O. Box 10502, New Delhi 110067 (India); Kalkal, S. [Deptartment of Physics and Astrophysics, Delhi University, Delhi 110007 (India); Sugathan, P.; Golda, K.S.; Ahuja, R.; Gehlot, J.; Madhavan, N. [Inter University Accelerator Centre, P. O. Box 10502, New Delhi 110067 (India); Behera, B.R. [Deptartment of Physics, Panjab University, Chandigarh 160014 (India); Mandal, S.K. [Deptartment of Physics and Astrophysics, Delhi University, Delhi 110007 (India)

    2014-05-01

    The characteristics and performance of a new detector system developed for the study of low energy heavy ion binary reactions using the kinematic coincidence technique are presented. The detector system has been developed to carry out experiments such as multi-nucleon transfer reactions using the General Purpose Scattering Chamber (GPSC) facility at IUAC [1,2]. The detector system consists of a pair of two-dimensional position sensitive multi wire proportional counter (MWPC) and a ΔE−E gas ionization chamber. Both MWPC have an active area of 5×5 cm{sup 2}, and provide position signals in horizontal (X) and vertical (Y) plane, and timing signal for time of flight measurements. The main design feature of MWPC is the reduced wire pitch of 0.025 in. (0.635 mm) in all electrodes, giving uniform field and faster charge collection, and usage of 10μm diameter in anode frame which gives higher gains. The position resolution of the detectors was determined to be 0.45 mm FWHM and time resolution was estimated to be 400 ps FWHM. The detector could handle heavy ion count rates exceeding 100 kHz without any break down. The timing and position signals of the detectors are used for kinematic coincidence measurements and subsequent extraction of their mass and angular distributions. The ionization chamber has a conventional transverse field geometry with segmented anode providing multiple ΔE signals for nuclear charge (Z) identification. This article describes systematic study of these detectors in terms of efficiency, count rate handling capability, time, position and energy resolution.

  6. Proceedings of the heavy ion fusion workshop

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, R C [ed.

    1978-01-01

    These proceedings contain reviews of current laboratory programs dealing with inertial fusion driven by beams of heavy ions, as well as several individually abstracted invited talks, workshop reports and contributed papers.

  7. From heavy ions to exotic atoms

    OpenAIRE

    Indelicato, Paul; Trassinelli, Martino

    2005-01-01

    We review a number of experiments and theoretical calculations on heavy ions and exotic atoms, which aim at providing informations on fundamental interactions. Among those are propositions of experiments for parity violation measurements in heavy ions and high-precision mesurements of He-like transition energies in highly charged ions. We also describe recent experiments on pionic atoms, that make use of highly-charged ion transitions to obtain accurate measurements of strong interaction shif...

  8. The Heavy-Ion Physics Programme with the ATLAS Detector

    CERN Document Server

    Rosselet, L

    2008-01-01

    The CERN LHC will collide lead ions at $\\sqrt{s}=5.5$ TeV per nucleon pair and will provide crucial information about the formation of a quark--gluon plasma at the highest temperatures and densities ever created in the laboratory. We report on an updated evaluation of the ATLAS potential to study heavy--ion physics. The ATLAS detector will perform especially well for high $p_T$ phenomena even in the presence of the high--multiplicity soft background expected from lead-lead collisions, and most of the detector subsystems retain their nearly full capability. ATLAS will study a full range of observables which characterize the hot and dense medium formed in heavy--ion collisions. In addition to global measurements such as particle multiplicities and collective flow, heavy--quarkonia suppression, jet quenching and the modification of jets passing in the dense medium will be accessible. ATLAS will also study forward physics and ultraperipheral collisions using Zero Degree Calorimeters.

  9. The Heavy-Ion Physics Programme with the ATLAS Detector

    CERN Document Server

    Rosselet, L

    2008-01-01

    The CERN LHC will collide lead ions at sqrt(s)=5.5 TeV per nucleon pair and will provide crucial information about the formation of a quark gluon plasma at the highest temperatures and densities ever created in the laboratory. We report on an updated evaluation of the ATLAS potential to study heavy-ion physics. The ATLAS detector will perform especially well for high pT phenomena even in the presence of the high-multiplicity soft background expected from lead-lead collisions, and most of the detector subsystems retain their nearly full capability. ATLAS will study a full range of observables which characterize the hot and dense medium formed in heavy-ion collisions. In addition to global measurements such as particle multiplicities and collective flow, heavy-quarkonia suppression, jet quenching and the modification of jets passing in the dense medium will be accessible to ATLAS. ATLAS will also study forward physics and ultraperipheral collisions using Zero Degree Calorimeters.

  10. Optical model calculations of heavy-ion target fragmentation

    Science.gov (United States)

    Townsend, L. W.; Wilson, J. W.; Cucinotta, F. A.; Norbury, J. W.

    1986-01-01

    The fragmentation of target nuclei by relativistic protons and heavy ions is described within the context of a simple abrasion-ablation-final-state interaction model. Abrasion is described by a quantum mechanical formalism utilizing an optical model potential approximation. Nuclear charge distributions of the excited prefragments are calculated by both a hypergeometric distribution and a method based upon the zero-point oscillations of the giant dipole resonance. Excitation energies are estimated from the excess surface energy resulting from the abrasion process and the additional energy deposited by frictional spectator interactions of the abraded nucleons. The ablation probabilities are obtained from the EVA-3 computer program. Isotope production cross sections for the spallation of copper targets by relativistic protons and for the fragmenting of carbon targets by relativistic carbon, neon, and iron projectiles are calculated and compared with available experimental data.

  11. The 2015 Heavy-Ion Run of the LHC

    CERN Document Server

    Jowett, John; Bruce, Roderik; Giovannozzi, Massimo; Hermes, Pascal; Höfle, Wolfgang; Lamont, Mike; Mertens, Tom; Redaelli, Stefano; Schaumann, Michaela; Uythoven, Jan; Wenninger, Jorg

    2016-01-01

    In late 2015 the LHC collided lead nuclei at a beam energy of 6.37 Z TeV, chosen to match the 5.02 TeV per colliding nucleon pair of the p-Pb collision run in 2013. In so doing, it surpassed its design luminosity by a factor of 2. Besides the higher energy, the operational configuration had a number of new features with respect to the previous Pb-Pb run at 3.5 Z TeV in 2011; unusual bunch patterns providing collisions in the LHCb experiment for the first time, luminosity levelling and sharing requirements, a vertical displacement of the interaction point in the ALICE experiment, and operation closer to magnet quench limits with mitigation measures. We present a summary of the commissioning and operation and what has been learned in view of future heavy-ion operation at higher luminosity.

  12. Chemical freeze-out in relativistic heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Jun Xu

    2017-09-01

    Full Text Available One surprising result in relativistic heavy-ion collisions is that the abundance of various particles measured in experiments is consistent with the picture that they reach chemical equilibrium at a temperature much higher than the temperature they freeze out kinetically. Using a multiphase transport model to study particle production in these collisions, we find, as an example, that the effective pion to nucleon ratio, which includes those from resonance decays, indeed changes very little during the evolution of the hadronic matter from the chemical to the kinetic freeze-out, and it is also accompanied by an almost constant specific entropy. We further use a hadron resonance gas model to illustrate the results from the transport model study.

  13. (Multi-nucleon transfer in the reactions 16O, 32S+208Pb

    Directory of Open Access Journals (Sweden)

    Hinde D.J.

    2011-10-01

    Full Text Available A detailed analysis of the projectile-like fragments detected at backward angles in the reactions 16O,32 S+208Pb at energies below the fusion barrier is presented. Excitation functions corresponding to nucleon transfer with ∆Z = 1 and ∆Z = 2 were extracted, indicating surprisingly large absolute probabilities at subbarrier energies. A comparison of 2p transfer probabilities with time-dependent Hartree-Fock calculations suggests strong pairing correlations between the two protons. Excitation energies in the projectile-like fragments ~15 MeV and ~25 MeV for the 16O and 32S-induced reactions, respectively, indicate the population of highly excited states in the residual nuclei. A comparison with expected optimum Q-values suggests large losses in kinetic energy of the projectile-like fragments. These highly inelastic (large excitation energies and complex (correlated few-nucleon transfer processes may be closely related to the depletion of fusion through tunnelling at sub-barrier energies.

  14. Mutagenic effects of heavy ion radiation in plants

    Science.gov (United States)

    Mei, M.; Deng, H.; Lu, Y.; Zhuang, C.; Liu, Z.; Qiu, Q.; Qiu, Y.; Yang, T. C.

    1994-01-01

    Genetic and developmental effects of heavy ions in maize and rice were investigated. Heavy particles with various charges and energies were accelerated at the BEVALAC. The frequency of occurrence of white-yellow stripes on leaves of plants developed from irradiated maize seeds increased linearly with dose, and high Linear Energy Transfer (LET) heavy charged particles, e.g., neon, argon, and iron, were 2-12 times as effective as gamma rays in inducing this type of mutation. The effectiveness of high-LET heavy ion in (1) inhibiting rice seedling growth, (2) reducing plant fertility, (3) inducing chromosome aberration and micronuclei in root tip cells and pollen mother cells of the first generation plants developed from exposed seeds, and (4) inducing mutation in the second generation, were greater than that of low-LET gamma rays. All effects observed were dose-dependent; however, there appeared to be an optimal range of doses for inducing certain types of mutation, for example, for argon ions (400 MeV/u) at 90-100 Gy, several valuable mutant lines with favorable characters, such as semidwarf, early maturity and high yield ability, were obtained. Experimental results suggest that the potential application of heavy ions in crop improvement is promising. Restriction-fragment-length-polymorphism (RFLP) analysis of two semidwarf mutants induced by argon particles revealed that large DNA alterations might be involved in these mutants.

  15. Heavy ion transfer reactions: Status and perspectives

    Indian Academy of Sciences (India)

    2015-11-27

    array (CLARA), extensive investigations of nuclear structure and reaction dynamics have been carried out. In the present paper aspects of these studies will be presented, focussing more closely on the reaction mechanism, ...

  16. Size of lethality target in mouse immature oocytes determined with accelerated heavy ions.

    Science.gov (United States)

    Straume, T; Dobson, R L; Kwan, T C

    1989-01-01

    Mouse immature oocytes were irradiated in vivo with highly charged, heavy ions from the Bevalac accelerator at the Lawrence Berkeley Laboratory. The particles used were 670-MeV/nucleon Si14+, 570-MeV/nucleon Ar18+, and 450-MeV/nucleon Fe26+. The cross-sectional area of the lethality target in these extremely radiosensitive cells was determined from fluence-response curves and information on energy deposition by delta rays. Results indicate a target cross-section larger than that of the nucleus, one which closely approximates the cross-sectional area of the entire oocyte. For 450-MeV/nucleon Fe26+ particles, the predicted target cross-sectional area is 120 +/- 16 microns2, comparing well with the microscopically determined cross-sectional area of 111 +/- 12 microns2 for these cells. The present results are in agreement with our previous target studies which implicate the oocyte plasma membrane.

  17. Polarization transfer measurement for H-1((d)over-right-arrow,(p)over-right-arrow)H-2 elastic scattering at 135 MeV/nucleon and three-nucleon force effects

    NARCIS (Netherlands)

    Sekiguchi, K; Sakai, H; Witala, H; Ermisch, K; Glockle, W; Golak, J; Hatano, M; Kamada, H; Kalantar-Nayestanaki, N; Kato, H; Maeda, Y; Nishikawa, J; Nogga, A; Ohnishi, T; Okamura, H; Saito, T; Sakamoto, N; Sakoda, S; Satou, Y; Suda, K; Tamii, A; Uchigashima, T; Uesaka, T; Wakasa, T; Yako, K

    The deuteron-to-proton polarization-transfer coefficients for d-p elastic scattering were precisely measured with an incoming deuteron energy of 135 MeV/nucleon at the RIKEN Accelerator Research Facility. The data are compared to theoretical predictions based on exact solution's of the three-nucleon

  18. Failla Memorial lecture. The future of heavy-ion science in biology and medicine.

    Science.gov (United States)

    Tobias, C A

    1985-07-01

    Interplanetary space contains fluxes of fast moving atomic nuclei. The distribution of these reflects the atomic composition of the universe, and such particles may pose limitations for space flight and for life in space. Over the past 50 years, since the invention of Ernest Lawrence's cyclotron, advances in accelerator technology have permitted the acceleration of charged nuclei to very high velocities. Currently, beams of any stable isotope species up to uranium are available at kinetic energies of several hundred MeV/nucleon at the Berkeley Bevalac. Recently, new areas of particle physics research relating to the mechanisms of spallation and fission have opened up for investigation, and it is now realistic to search for nuclear super-dense states that might be produced in heavy nuclear collisions. The heavy ions hold interest for a broad spectrum of research because of their effectiveness in producing a series of major lesions in DNA along single particle tracks and because of the Bragg depth ionization properties that allow the precise deposition of highly localized doses deep in the human body. Individual heavy ions can also interrupt the continuity of membraneous regions in cells. Heavy ions, when compared to low-LET radiation, have increased effectiveness for mammalian cell lethality, chromosome mutations, and cell transformation. The molecular mechanisms are not completely understood but appear to involve fragmentation and reintegration of DNA. Cells attempt to repair these lesions, and many of the deleterious effects are due to misrepair or misrejoining of DNA. Heavy ions do not require the presence of oxygen for producing their effects, and hypoxic cells in necrotic regions have nearly the same sensitivity as cells in well-oxygenated tissues. Heavy ions are effective in delaying or blocking the cell division process. Heavy ions are also strong enhancers of viral-induced cell transformation, a process that requires integration of foreign DNA. Some cell

  19. Heavy ion acceleration in the radiation pressure acceleration and breakout afterburner regimes

    Science.gov (United States)

    Petrov, G. M.; McGuffey, C.; Thomas, A. G. R.; Krushelnick, K.; Beg, F. N.

    2017-07-01

    We present a theoretical study of heavy ion acceleration from ultrathin (20 nm) gold foil irradiated by high-intensity sub-picosecond lasers. Using two-dimensional particle-in-cell simulations, three laser systems are modeled that cover the range between femtosecond and picosecond pulses. By varying the laser pulse duration we observe a transition from radiation pressure acceleration (RPA) to the relativistic induced transparency (RIT) regime for heavy ions akin to light ions. The underlying physics of beam formation and acceleration is similar for light and heavy ions, however, nuances of the acceleration process make the heavy ions more challenging. A more detailed study involving variation of peak laser intensity I 0 and pulse duration τFWHM revealed that the transition point from RPA to RIT regime depends on the peak laser intensity on target and occurs for pulse duration {τ }{{F}{{W}}{{H}}{{M}}}{{R}{{P}}{{A}}\\to {{R}}{{I}}{{T}}}[{{f}}{{s}}]\\cong 210/\\sqrt{{I}0[{{W}} {{{cm}}}-2]/{10}21}. The most abundant gold ion and charge-to-mass ratio are Au51+ and q/M ≈ 1/4, respectively, half that of light ions. For ultrathin foils, on the order of one skin depth, we established a linear scaling of the maximum energy per nucleon (E/M)max with (q/M)max, which is more favorable than the quadratic one found previously. The numerical simulations predict heavy ion beams with very attractive properties for applications: high directionality (high fluxes (>1011 ions sr-1) and energy (>20 MeV/nucleon) from laser systems delivering >20 J of energy on target.

  20. Heavy ion induced mutation in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy ions, He, C, Ar and Ne were irradiated to the seeds of Arabidopsis thaliana for inducing the new mutants. In the irradiated generation (M{sub 1}), germination and survival rate were observed to estimate the relative biological effectiveness in relation to the LET including the inactivation cross section. Mutation frequencies were compared by using three kinds of genetic loci after irradiation with C ions and electrons. Several interesting new mutants were selected in the selfed progenies of heavy ion irradiated seeds. (author)

  1. European heavy ion ICF driver development

    CERN Document Server

    Plass, Günther

    1996-01-01

    Approaches in Europe to heavy ion induced Inertial Confinement Fusion are oriented toward the linac-plus- storage ring technique. Despite the very limited support of this work, technical pro gress was achieved in some important areas. For the immediate future, a substantial intensity upgrade of the GSI accelerator facilities at Darmstadt is being implemented, leading to specific energy depositions of the order of 100 kJ/g and plasma temperatures of 10 to 20 eV. For the longer term, a conceptual design study of a heavy ion based Ignition Facility is being initiated.

  2. Jets in heavy ion collisions with CMS

    CERN Document Server

    Salur, Sevil

    2016-01-01

    Jet physics in heavy ion collisions is a rich field which has been rapidly evolving since the first observations of medium interactions at RHIC through back-to-back hadron correlations and at LHC via reconstructed jets. In order to completely characterize the final state via jet-medium interactions and distinguish between competing energy loss mechanisms complementary and robust jet observables are investigated. Latest developments of jet finding techniques and their applications to heavy ion environments are discussed with an emphasis given on experimental results from CMS experiment.

  3. Fifth high-energy heavy-ion study

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    This was the fifth of a continuing series of summer studies held at LBL to discuss high energy heavy ion collisions. Recently, a similar meeting has been held on alternate years at GSI (Darmstadt); and, in 1979, we held a meeting at LBL exclusively devoted to ultra-relativistic nuclear collisions. Two new features distinguish this study from earlier meetings in the series. First, the energy range for discussion was broadened by including collisions from about 20 MeV/nucleon to the highest available in the cosmic radiation. The lower range, particularly below 100 MeV/nucleon, will be under intense study in the near future with machines such as the upgraded Bevalac, Michigan State University Superconducting Cyclotron, GANIL in France, and the SC at CERN. Recently, the high energy collision regime has been expanded by the successful operation of the CERN ISR with alpha particles. Second, in addition to an extensive program of invited talks, we decided for the first time to actively solicit contributions. Forty-seven individual items from the conference were prepared separately for the data base. (GHT)

  4. A heavy load for heavy ions

    CERN Multimedia

    2003-01-01

    On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

  5. HIGH DENSITY QCD WITH HEAVY-IONS

    CERN Multimedia

    The Addendum 1 to Volume 2 of the CMS Physics TDR has been published The Heavy-Ion analysis group completed the writing of a TDR summarizing the CMS plans in using heavy ion collisions to study high density QCD. The document was submitted to the LHCC in March and presented in the Open Session of the LHCC on May 9th. The study of heavy-ion physics at the LHC is promising to be very exciting. LHC will open a new energy frontier in ultra-relativistic heavy-ion physics. The collision energy of heavy nuclei at sNN = 5.5 TeV will be thirty times larger than what is presently available at RHIC. We will certainly probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research programme is to study the fundamental theory of the strong interaction - Quantum Chromodynamics (QCD) - in extreme conditions of temperature, density and parton momentum fraction (low-x). Such studies, with impressive experimental and theoretical advances in recent years thanks to the wealth of high-qua...

  6. Working group report: Heavy ion physics

    Indian Academy of Sciences (India)

    Working group report: Heavy ion physics. Coordinator: JAN-E ALAM1. Contributors: K Assamagan2, S Chattopadhyay1, R Gavai3, Sourendu Gupta3,. B Layek4, S Mukherjee3, R Ray3, Pradip K Roy5 and A Srivastava4. 1Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064, India. 2Brookhaven National ...

  7. Superconducting heavy-ion accelerating structures

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.

    1996-08-01

    This paper briefly reviews the technical history of superconducting ion-accelerating structures. Various superconducting cavities currently used and being developed for use in ion linacs are discussed. Principal parameters and operational characteristics of superconducting structures in active use at various heavy-ion facilities are described.

  8. Working group report: Heavy ion physics

    Indian Academy of Sciences (India)

    The 8th workshop on high energy physics phenomenology (WHEPP-8) was held at the Indian Institute of Technology, Mumbai, India during January 5–16, 2004. One of the four working groups, group III was dedicated to QCD and heavy ion physics (HIC). The present manuscript gives a summary of the activities of group III ...

  9. Green's function methods in heavy ion shielding

    Science.gov (United States)

    Wilson, John W.; Costen, Robert C.; Shinn, Judy L.; Badavi, Francis F.

    1993-01-01

    An analytic solution to the heavy ion transport in terms of Green's function is used to generate a highly efficient computer code for space applications. The efficiency of the computer code is accomplished by a nonperturbative technique extending Green's function over the solution domain. The computer code can also be applied to accelerator boundary conditions to allow code validation in laboratory experiments.

  10. Metastable states of highly excited heavy ions

    Science.gov (United States)

    Pegg, D. J.; Griffin, P. M.; Sellin, I. A.; Smith, W. W.; Donnally, B.

    1973-01-01

    Description of the method used and results obtained in an experimental study of the metastable states of highly stripped heavy ions, aimed at determining the lifetimes of such states by the rates of autoionization and radiation. The significance and limitations of the results presented are discussed.

  11. Relativistic heavy-ion physics: Experimental overview

    Indian Academy of Sciences (India)

    highlights from the first run of the relativistic heavy-ion collider at BNL and the 15 year research programme at the super ... The energy dependence of the charged particle density dNch/dη, normalized to the num- ..... meson both in the dropping mass and the collision broadening scenarios, is almost as high at RHIC as at ...

  12. Multifragmentation and dynamics in heavy ion collisions

    Indian Academy of Sciences (India)

    A midrapidity zone formed in heavy-ion collisions has been investigated through special selections of light .... lished from analysing charged particles emitted at velocities between those characteristic of projectilelike .... only, one low and one high, are displayed (more complete results are given in [15]). For the QP source ...

  13. Quarkonium production in heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Arnaldi Roberta

    2014-03-01

    Full Text Available The production of quarkonium states plays a crucial role among the probes to investigate the formation of the plasma of quarks and gluons (QGP in heavy-ion collisions. A review of the charmonium and bottomonium production, mainly focussing on the latest results from the LHC experiments, is presented.

  14. Heavy-Ion Physics in a Nutshell

    Directory of Open Access Journals (Sweden)

    Hirano Tetsufumi

    2013-05-01

    Full Text Available The physics of quark gluon plasma (QGP and heavy ion collisions at the collider energies is briefly reviewed. We first discuss about the discovery of a nearly perfect fluidity of the QGP. We also highlights recent topics on responses of the QGP to initial deformation and propagation of a jet.

  15. Minor actinide fission induced by multi-nucleon transfer reaction in inverse kinematics

    Directory of Open Access Journals (Sweden)

    Taieb J.

    2010-03-01

    Full Text Available In the framework of nuclear waste incineration and design of new generation nuclear reactors, experimental data on fission probabilities and on fission fragment yields of minor actinides are crucial to design prototypes. Transfer-induced fission has proven to be an efficient method to study fission probabilities of actinides which cannot be investigated with standard techniques due to their high radioactivity. We report on the preliminary results of an experiment performed at GANIL that investigates fission probabilities with multi-nucleon transfer reactions in inverse kinematics between a 238U beam on a 12C target. Actinides from U to Cm were produced with an excitation energy range from 0 to 30 MeV. In addition, inverse kinematics allowed to characterize the fission fragments in mass and charge. A key point of the analysis resides in the identification of the actinides produced in the different transfer channels. The new annular telescope SPIDER was used to tag the target-like recoil nucleus of the transfer reaction and to determine the excitation energy of the actinide. The fission probability for each transfer channel is accessible and the preliminary results for 238U are promising.

  16. Measuring one nucleon transfer reaction 24Mg( p, d)23Mg for astrophysical reaction rates

    Science.gov (United States)

    Lee, E. J.; Chae, K. Y.

    2017-12-01

    The level structure of a radionuclide 23Mg has been studied by using the 24Mg( p, d)23Mg one nucleon transfer reaction measurement for the astrophysical 19Ne(α, γ)23Mg reaction rate. A 41 MeV proton beam was produced and accelerated at the 25 MV tandem accelerator of the Holifield Radioactive Ion Beam Facility of the Oak Ridge National Laboratory in the United States. The beam particles impinged on an isotopically-enriched 24Mg solid target. Angular distributions of recoiling deuterons were extracted by using a large area silicon strip detector array. By comparing the experimentally-obtained angular distributions with zero range distorted wave Born approximation calculations, spins and parities of three energy levels of 23Mg could be constrained for the first time, which is very important information needed to understand the 19Ne(α, γ)23Mg reaction rate.

  17. Heavy ion action on single cells: Cellular inactivation capability of single accelerated heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Kost, M.; Pross, H.D.; Russmann, C.; Schneider, E.; Kiefer, J.; Kraft, G.; Lenz, G.; Becher, W. [Gesellschaft fuer Schwerionenforschung m.b.H., Darmstadt (Germany)

    1994-12-31

    Heavy ions (HZE-particles) constitute an important part of radiation in space. Although their number is small the high amount of energy transferred by individual particles may cause severe biological effects. Their investigation requires special techniques which were tested by experiments performed at the UNILAC at the GSI (Darmstadt). Diploid yeast was used which is a suitable eucaryotic test system because of its resistance to extreme conditions like dryness and vacuum. Cells were placed on nuclear track detector foils and exposed to ions of different atomic number and energy. To assess the action of one single ion on an individual cell, track parameters and the respective colony forming abilities (CFA) were determined with the help of computer aided image analysis. There is mounting evidence that not only the amount of energy deposited along the particle path, commonly given by the LET, is of importance but also the spatial problem of energy deposition at a submicroscopical scale. It is virtually impossible to investigate track structure effects in detail with whole cell populations and (globally applied) high particle fluences. It is, therefore, necessary to detect the action of simple ions in individual cells. The results show that the biological action depends on atomic number and specific energy of the impinging ions, which can be compared with model calculations of recent track structure models.

  18. Heavy ion action on single cells: Cellular inactivation capability of single accelerated heavy ions

    Science.gov (United States)

    Kost, M.; Pross, H.-D.; Russmann, C.; Schneider, E.; Kiefer, J.; Kraft, G.; Lenz, G.; Becher, W.

    1994-01-01

    Heavy ions (HZE-particles) constitute an important part of radiation in space. Although their number is small the high amount of energy transferred by individual particles may cause severe biological effects. Their investigation requires special techniques which were tested by experiments performed at the UNILAC at the GSI (Darmstadt). Diploid yeast was used which is a suitable eucaryotic test system because of its resistance to extreme conditions like dryness and vacuum. Cells were placed on nuclear track detector foils and exposed to ions of different atomic number and energy. To assess the action of one single ion on an individual cell, track parameters and the respective colony forming abilities (CFA) were determined with the help of computer aided image analysis. There is mounting evidence that not only the amount of energy deposited along the particle path, commonly given by the LET, is of importance but also the spatial problem of energy deposition at a submicroscopical scale. It is virtually impossible to investigate track structure effects in detail with whole cell populations and (globally applied) high particle fluences. It is, therefore, necessary to detect the action of simple ions in individual cells. The results show that the biological action depends on atomic number and specific energy of the impinging ions, which can be compared with model calculations of recent track structure models.

  19. Exotic hadrons from heavy ion collisions

    Science.gov (United States)

    Cho, Sungtae; Hyodo, Tetsuo; Jido, Daisuke; Ko, Che Ming; Lee, Su Houng; Maeda, Saori; Miyahara, Kenta; Morita, Kenji; Nielsen, Marina; Ohnishi, Akira; Sekihara, Takayasu; Song, Taesoo; Yasui, Shigehiro; Yazaki, Koichi

    2017-07-01

    High energy heavy ion collisions are excellent ways for producing heavy hadrons and composite particles, including the light (anti)nuclei. With upgraded detectors at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), it has become possible to measure hadrons beyond their ground states. Therefore, heavy ion collisions provide a new method for studying exotic hadrons that are either molecular states made of various hadrons or compact system consisting of multiquarks. Because their structures are related to the fundamental properties of Quantum Chromodynamics (QCD), studying exotic hadrons is currently one of the most active areas of research in hadron physics. Experiments carried out at various accelerator facilities have indicated that some exotic hadrons may have already been produced. The present review is a summary of the current understanding of a selected set of exotic particle candidates that can be potentially measured in heavy ion collisions. It also includes discussions on the production of resonances, exotics and hadronic molecular states in these collisions based on the coalescence model and the statistical model. A more detailed discussion is given on the results from these models, leading to the conclusion that the yield of a hadron that is a compact multiquark state is typically an order of magnitude smaller than if it is an excited hadronic state with normal quark numbers or a loosely bound hadronic molecule. Attention is also given to some of the proposed heavy exotic hadrons that could be produced with sufficient abundance in heavy ion collisions because of the significant numbers of charm and bottom quarks that are produced at RHIC and even larger numbers at LHC, making it possible to study them in these experiments. Further included in the discussion are the general formalism for the coalescence model that involves resonance particles and its implication on the present estimated yield for resonance production. Finally

  20. Dipolar degrees of freedom and Isospin equilibration processes in Heavy Ion collisions

    CERN Document Server

    Papa, M; Acosta, L; Amorini, F; Agodi, C; Anzalone, A; Auditore, L; Cardella, G; Cavallaro, S; Chatterjee, M B; De Filippo, E; Francalanza, L; Geraci, E; Grassi, L; Gnoffo, B; Han, J; La Guidara, E; Lanzalone, G; Lombardo, I; Pagano, C Maiolino T Minniti A; Pagano, E V; Pirrone, S; Politi, G; Porto, F; Quattrocchi, L; Rizzo, F; Rosato, E; Russotto, P; Trifirò, A; Trimarchi, M; Verde, G; Vigilante, and M

    2015-01-01

    Background: In heavy ion collision at the Fermi energies Isospin equilibration processes occur- ring when nuclei with different charge/mass asymmetries interacts have been investigated to get information on the nucleon-nucleon Iso-vectorial effective interaction. Purpose: In this paper, for the system 48Ca +27 Al at 40 MeV/nucleon, we investigate on this process by means of an observable tightly linked to isospin equilibration processes and sensitive in exclusive way to the dynamical stage of the collision. From the comparison with dynamical model calculations we want also to obtain information on the Iso-vectorial effective microscopic interaction. Method: The average time derivative of the total dipole associated to the relative motion of all emitted charged particles and fragments has been determined from the measured charges and velocities by using the 4? multi-detector CHIMERA. The average has been determined for semi- peripheral collisions and for different charges Zb of the biggest produced fragment. E...

  1. Jet Physics in Heavy Ion Collisions

    Science.gov (United States)

    Salur, Sevil

    2017-09-01

    Jet studies in heavy ion collisions have been rapidly evolving since the first observations of medium interactions at RHIC through back to back hadron correlations and at LHC via reconstructed jets. In order to completely characterize the final state via jet-medium interactions and distinguish between competing energy loss mechanisms, complementary and robust jet observables are investigated. In this talk, with an emphasis on experimental results from LHC, we will discuss the latest developments of jet finding techniques and their applications on new jet structure observables in heavy ion environments. These new measurements could be used to differentiate whether the medium affects the jet formation process from the hard process through hadronization, or whether the parton loses energy to the medium with the showers only affected at much later stages.

  2. Three-stage classical molecular dynamics model for simulation of heavy-ion fusion

    Directory of Open Access Journals (Sweden)

    Godre Subodh S.

    2015-01-01

    Full Text Available A three-stage Classical Molecular Dynamics (3S-CMD approach for heavy-ion fusion is developed. In this approach the Classical Rigid-Body Dynamics simulation for heavy-ion collision involving light deformed nucleus is initiated on their Rutherford trajectories at very large initial separation. Collision simulation is then followed by relaxation of the rigid-body constrains for one or both the colliding nuclei at distances close to the barrier when the trajectories of all the nucleons are obtained in a Classical Molecular Dynamics approach. This 3S-CMD approach explicitly takes into account not only the long range Coulomb reorientation of the deformed collision partner but also the internal vibrational excitations of one or both the nuclei at distances close to the barrier. The results of the dynamical simulation for 24Mg+208Pb collision show significant modification of the fusion barrier and calculated fusion cross sections due to internal excitations.

  3. The holifield heavy ion research facility

    Science.gov (United States)

    Jones, C. M.; Alton, G. D.; Ball, J. B.; Biggerstaff, J. A.; Dowling, D. T.; Erb, K. A.; Haynes, D. L.; Hoglund, D. E.; Hudson, E. D.; Juras, R. C.; Lane, S. N.; Ludemann, C. A.; Martin, J. A.; Mosko, S. W.; Olsen, D. K.; Richardson, E. G.; Stelson, P. H.; Ziegler, N. F.

    1986-02-01

    The Holifield Heavy Ion Research Facility has been in routine operation since July 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we discuss our operational experience and recent development activities.

  4. The heavy-ion magnetic spectrometer PRISMA

    Energy Technology Data Exchange (ETDEWEB)

    Stefanini, A.M. E-mail: alberto.stefanini@lnl.infn.it; Corradi, L.; Maron, G.; Pisent, A.; Trotta, M.; Vinodkumar, A.M.; Beghini, S.; Montagnoli, G.; Scarlassara, F.; Segato, G.F.; De Rosa, A.; Inglima, G.; Pierroutsakou, D.; Romoli, M.; Sandoli, M.; Pollarolo, G.; Latina, A

    2002-04-22

    PRISMA is a magnetic spectrometer for heavy ions under construction at Legnaro, with very large solid angle (80 msr), wide momentum acceptance ({+-} 10%) and good mass resolution via TOF measurement; it will be dedicated to the study of nuclear dynamics and nuclear structure with stable and exotic ion beams. This is a review of its main features and of the present status of the project.

  5. The Holifield Heavy Ion Research Facility

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.; Alton, G.D.; Ball, J.B.; Biggerstaff, J.A.; Dowling, D.T.; Erb, K.A.; Haynes, D.L.; Hoglund, D.E.; Hudson, E.D.; Juras, R.C.

    1987-01-01

    Development of the Holifield facility has continued with resulting improvements in the number of ion species provided, ion energy for tandem-only operations, and utilization efficiency. The Holifield Heavy Ion Research Facility (HHIRF) is located at the Oak Ridge National Laboratory and operated as a national user facility for research in heavy ion science. The facility operates two accelerators: an NEC pelletron tandem accelerator designed to operate at terminal potentials up to 25 MV and the Oak Ridge Isochronous Cyclotron (ORIC) which has been modified to serve as an energy booster for beams from the tandem accelerator. The principal experimental devices of the facility include a broad range spectrograph (ME/q/sup 2/ = 225) equipped with a vertical drift chamber detector system, a 4..pi.. spin spectrometer equipped with 72 NaI detectors (Ge detectors and BGO compton-suppression units can be used in place of the NaI detectors), a time-of-flight spectrometer, a 1.6-m scattering chamber, a heavy-ion/light-ion detector (HILI) which will be used for studying inverse reactions, a split-pole spectrograph, and a velocity filter. In this report, we will discuss our recent development activities, operational experience, and future development plans.

  6. Heavy Ion Physics with the ATLAS Detector

    CERN Multimedia

    Takai, H

    2003-01-01

    I guess the first thing that comes to people's mind is why is an experiment such as ATLAS interested in heavy ion physics. What is heavy ion physics anyway? The term heavy ion physics refers to the study of collisions between large nuclei such as lead, atomic number 208. But why would someone collide something as large and extensive as lead nuclei? When two nuclei collide there is a unique opportunity to study QCD at extreme energy densities. This said why do we think ATLAS is a good detector to study this particular physics? Among many of the simultaneous collisions that takes place when two nuclei encouter, hard scattering takes place. The unique situation now is that before hadronization partons from hard scattering may feel the surrounding media serving as an ideal probe for the matter formed in these collisions. As a consequence of this, jets may be quenched and their properties, e.g. fragmentation function or cone radius, modified when compared to proton-proton collisions. This is precisely where ATL...

  7. Potential and limitations of nucleon transfer experiments with radioactive beams at REX-ISOLDE

    CERN Document Server

    Gund, C.; Cub, J.; Dietrich, A.; Hartlein, T.; Lenske, H.; Pansegrau, D.; Richter, A.; Scheit, H.; Schrieder, G.; Schwalm, D.

    2001-01-01

    As a tool for studying the structure of nuclei far off stability the technique of $\\gamma$-ray spectroscopy after low-energy single-nucleon transfer reactions with radioactive nuclear beams in inverse kinematics was investigated. Modules of the MINIBALL germanium array and a thin position-sensitive parallel plate avalanche counter (PPAC) to be employed in future experiments at REX-ISOLDE were used in a test experiment performed with a stable $^{36}$S beam on deuteron and $^{9}$Be targets. It is demonstrated that the Doppler broadening of $\\gamma$ lines detected by the MINIBALL modules is considerably reduced by exploiting their segmentation, and that for beam intensities up to 10$^{6}$ particles/s the PPAC positioned around zero degrees with respect to the beam axis allows not only to significantly reduce the gamma background by requiring coincidences with the transfer products but also to control the beam and its intensity by single particle counting. The predicted large neutron pickup cross-sections of neut...

  8. Stopped nucleons in configuration space

    Energy Technology Data Exchange (ETDEWEB)

    Bialas, Andrzej [Jagellonian Univ., Krakow (Poland); Bzdak, Adam [AGH - Univ. of Science and Technology, Krakow (Poland); Koch, Volker [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-05-09

    In this note, using the colour string model, we study the configuration space distribution of stopped nucleons in heavy-ion collisions. We find that the stopped nucleons from the target and the projectile end up separated from each other by the distance increasing with the collision energy. In consequence, for the center of mass energies larger than 6 or 10 GeV (depending on the details of the model) it appears that the system created is not in thermal and chemical equilibrium, and the net baryon density reached is likely not much higher than that already present in the colliding nuclei.

  9. Studies of Heavy-Ion Reactions and Transuranic Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, W. Udo [Univ. of Rochester, NY (United States). Dept. of Chemistry. Dept. of Physics

    2016-07-28

    Studies of heavy-ion reactions and transuranic nuclei performed by the University of Rochester Nuclear Science Research Group have been successful in furthering experimental systematics and theoretical understanding of the behavior of nuclear systems excited to their limits of stability. The theoretical results explain specifically the “boiling” and “vaporization” of atomic nuclei, but are more generally applicable to isolated, quantal many-particle systems which, under thermal or mechanical stresses, all disintegrate by evaporation, via surface cluster emission, or via fission-like processes. Accompanying experimental investigations by the group have demonstrated several new types of dynamical instability of nuclei: In central, “head-on” collisions, target nuclei exhibit limited ability to stop energetic projectile nuclei and to dissipate the imparted linear momentum. Substantial matter overlap (“neck”) between projectile and target nuclei, which is observed at elevated collision energies, can be stretched considerably and break at several places simultaneously. These results provide new testing grounds for microscopic theory of the cohesion of nuclear matter. This property has remained elusive, even though the elementary nucleon-nucleon forces are well known since some time. Technical R&D has resulted in a detailed characterization of a novel plastic material, which can now be used in the design of sensitive diagnostic systems for various types of radio-activity. Innovative application of powerful laser systems has produced intense, controllable sources of exotic particle radioactivity for nuclear investigations. Several students have received their Ph.D. degree in experimental nuclear science for their work on basic nuclear research or R&D projects.

  10. Jet Quenching in Relativistic Heavy Ion Collisions at the LHC

    CERN Document Server

    Angerami, Aaron

    Jet production in relativistic heavy ion collisions is studied using Pb+Pb collisions at a center of mass energy of 2.76 TeV per nucleon. The measurements reported here utilize data collected with the ATLAS detector at the LHC from the 2010 Pb ion run corresponding to a total integrated luminosity of 7 μb−1. The results are obtained using fully reconstructed jets using the anti-kt algorithm with a per-event background subtraction procedure. A centrality-dependent modification of the dijet asymmetry distribution is observed, which indicates a higher rate of asymmetric dijet pairs in central collisions relative to peripheral and pp collisions. Simultaneously the dijet angular correlations show almost no centrality dependence. These results provide the first direct observation of jet quenching. Measurements of the single inclusive jet spectrum, measured with jet radius parameters R = 0.2,0.3,0.4 and 0.5, are also presented. The spectra are unfolded to correct for the finite energy resolution introduced by bot...

  11. Bottomonium production in heavy-ion collisions at STAR

    CERN Document Server

    Vertesi, Robert

    2015-01-01

    Bottomonium measurements provide unique insight into hot and cold nuclear matter effects present in the medium that is formed in high-energy heavy-ion collisions. Recent STAR results show that in $\\sqrt{s_{NN}}$ = 200 GeV central Au+Au collisions the $\\Upsilon$(1S) state is suppressed more than if only cold nuclear matter effects were present, and the excited state yields are consistent with a complete suppression. In 2012, STAR also collected 263.4 $\\mu$b$^{-1}$ high-energy-electron triggered data in U+U collisions at $\\sqrt{s_{NN}}$= 193 GeV. Central U+U collisions, with an estimated 20% higher energy density than in central Au+Au data, extend the $\\Upsilon$(1S+2S+3S) and Upsilon(1S) nuclear modification trends observed in Au+Au towards higher number of participant nucleons, and confirm the suppression of the $\\Upsilon$(1S) state. We see a hint with 1.8 sigma significance that the $\\Upsilon$(2S+3S) excited states are not completely suppressed in U+U collisions. These data support the sequential in-medium qu...

  12. Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions

    CERN Document Server

    Bravina, L V; Korotkikh, V L; Lokhtin, I P; Malinina, L V; Nazarova, E N; Petrushanko, S V; Snigirev, A M; Zabrodin, E E

    2015-01-01

    The possible mechanisms contributing to anisotropic flow fluctuations in relativistic heavy ion collisions are discussed. The LHC data on event-by-event harmonic flow coefficients measured in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted within the HYDJET++ model. To compare the model results with the experimental data the unfolding procedure is employed. It is shown that HYDJET++ correctly reproduces dynamical fluctuations of elliptic and triangular flows and related to it eccentricity fluctuations of the initial state.

  13. Direct photons in heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Baeuchle, Bjoern

    2010-12-13

    Direct photon emission from heavy-ion collisions has been calculated and compared to available experimental data. Three different models have been combined to extract direct photons from different environments in a heavy-ion collision: Thermal photons from partonic and hadronic matter have been extracted from relativistic, non-viscous 3+1-dimensional hydrodynamic calculations. Thermal and non-thermal photons from hadronic interactions have been calculated from relativistic transport theory. The impact of different physics assumptions about the thermalized matter has been studied. The models used for the determination of photons from both hydrodynamic and transport calculations have been elucidated and their numerical properties tested. The origin of direct photons, itemised by emission stage, emission time, channel and baryon number density, has been investigated for various systems, as have the transverse momentum spectra and elliptic flow patterns of direct photons. Taking into account the full (vacuum) spectral function of the rho-meson decreases the direct photon emission by approximately 10% at low photon transverse momentum. In all systems that have been considered -- heavy-ion collisions at E{sub lab}=35 AGeV and 158 AGeV, (s{sub NN}){sup 1/2}=62.4 GeV, 130 GeV and 200 GeV -- thermal emission from a system with partonic degrees of freedom is greatly enhanced over that from hadronic systems, while the difference between the direct photon yields from a viscous and a non-viscous hadronic system (transport vs. hydrodynamics) is found to be very small. Predictions for direct photon emission in central U+U-collisions at 35 AGeV have been made. (orig.)

  14. Hyperons polarization in heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Baznat Mircea

    2017-01-01

    Full Text Available We study the structure of vorticity and hydrodynamic helicity fields in peripheral heavy-ion collisions using the kinetic Quark-Gluon Strings Model. The angular momentum which is a source of P-odd observables is preserved within this model with a good accuracy. We observe the formation of specific toroidal structures of vorticity field. Their existence is mirrored in the polarization of hyperons of the percent order. The observed qualitative energy dependence of polarization was predicted earlier and is quantified now.

  15. Heavy Ions in 2011 and beyond

    CERN Document Server

    Jowett, J; Bruce, R; Carli, C; Manglunki, D; Mertens, T; Wollmann, D

    2011-01-01

    The LHC's first heavy ion run set - and tested - the operational pattern for 2011 and later years: a rapid commissioning strategy intended to ensure delivery of integrated luminosity despite the risks associated with the short time-frame. It also gave us hard data to test our understanding of the beam physics that will limit performance. The 2010 experience is fed into the commissioning plan, parameter choices and projected performance for 2011. The prospects for future stages of the LHC ion program, Pb-Pb collisions at higher energy and luminosity, hybrid collisions and other species, depend critically on the scheduling of certain hardware upgrades.

  16. Progress in understanding heavy-ion stopping

    Energy Technology Data Exchange (ETDEWEB)

    Sigmund, P., E-mail: sigmund@sdu.dk [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M (Denmark); Schinner, A. [Institut für Experimentalphysik, Johannes Kepler Universität, A-4040 Linz (Austria)

    2016-09-01

    We report some highlights of our work with heavy-ion stopping in the energy range where Bethe stopping theory breaks down. Main tools are our binary stopping theory (PASS code), the reciprocity principle, and Paul’s data base. Comparisons are made between PASS and three alternative theoretical schemes (CasP, HISTOP and SLPA). In addition to equilibrium stopping we discuss frozen-charge stopping, deviations from linear velocity dependence below the Bragg peak, application of the reciprocity principle in low-velocity stopping, modeling of equilibrium charges, and the significance of the so-called effective charge.

  17. Gamma-ray spectroscopy of neutron-rich actinides after multi-nucleon transfer reactions

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, Andreas; Birkenbach, Benedikt; Reiter, Peter [IKP, Universitaet zu Koeln (Germany); Corradi, Lorenzo [INFN - LNL (Italy); Szilner, Suzana [IRB Zagreb (Croatia); Collaboration: LNL 11.22-Collaboration

    2015-07-01

    Excited states in neutron-rich actinide Th and U nuclei were investigated after multi-nucleon transfer reactions employing the AGATA demonstrator and PRISMA setup at LNL (INFN, Italy). A primary 1 GeV {sup 136}Xe beam hitting a {sup 238}U target was used to produce the nuclei of interest in the actinide region. Beam-like reaction products in the Xe-region were identified and selected by the magnetic spectrometer PRISMA. Hence, fission fragments can be discriminated against surviving nuclei, DANTE-MCPs were installed within the target chamber to exploit kinematic coincidences between the binary reaction products which allows for clean conditions for in-beam γ-ray spectroscopy. Coincident γ-rays from excited states in beam- and target-like particles were measured with the position-sensitive AGATA HPGe detectors. An improved Doppler correction for both beam- and target-like nuclei is based on the novel γ-ray tracking technique. An extension of the ground-state rotational band in {sup 240}U and insights into n-rich Th isotopes were achieved. Based on relative cross-section distributions for various reaction channels, perspectives and limitations for the production of the hard-to-reach neutron-rich isotopes with this experimental method will be presented.

  18. Spectroscopy of Rn, Ra and Th isotopes using multi-nucleon transfer reactions

    CERN Document Server

    Cocks, J F C; Amzal, N; Butler, P A; Cann, K J; Greenlees, P T; Jones, G D; Asztalos, S; Clark, R M; Deleplanque, M A; Diamond, R M; Fallon, P; Lee, I Y; Macchiavelli, A O; MacLeod, R W; Stephens, F S; Jones, P; Julin, R; Broda, R; Fornal, B; Smith, J F; Lauritsen, T; Bhattacharya, P; Zhang, C T

    1999-01-01

    High-spin spectroscopy of Rn, Ra and Th isotopes has been performed. The nuclei have been populated using multi-nucleon transfer reactions involving a sup 2 sup 3 sup 2 Th target and a sup 1 sup 3 sup 6 Xe projectile. This type of reaction offers the only mechanism for populating high-spin states in many of these nuclei. Interleaving bands with opposite parities have been observed to high spin (approx 28(Planck constant/2 pi)) in sup 2 sup 1 sup 8 sup , sup 2 sup 2 sup 0 sup , sup 2 sup 2 sup 2 Rn, sup 2 sup 2 sup 2 sup , sup 2 sup 2 sup 4 sup , sup 2 sup 2 sup 6 sup , sup 2 sup 2 sup 8 Ra and sup 2 sup 2 sup 8 sup , sup 2 sup 3 sup 0 sup , sup 2 sup 3 sup 4 Th. A systematic study of the rotational alignment properties of octupole bands in radon, radium and thorium isotopes reveals information concerning the role of the octupole phonon and the onset of stable octupole deformation with increasing rotational frequency. Measurement of the magnitude of the intrinsic electric dipole moment, D sub 0 , provides addi...

  19. QCD and Heavy Ions RHIC Overview

    CERN Document Server

    Granier de Cassagnac, Raphael

    2010-01-01

    Nowadays, the most violent heavy ion collisions available to experimental study occur at the Relativistic Heavy Ion Collider (RHIC) of the Brookhaven National Laboratory. There, gold ions collide at psNN = 200 GeV. The early and most striking RHIC results were summarised in 2005 by its four experiments, BRAHMS, PHENIX, PHOBOS and STAR, in their so-called white papers [1, 2, 3, 4] that will be largely referenced thereafter. Beyond and after this, a wealth of data has been collected and analysed, providing additional information about the properties of the matter created at RHIC. It is categorically impossible to give a comprehensive review of these results in a 20 minutes talk or a 7 pages report. Here, I have made a selection of some of the most striking or intriguing signatures: jet quenching in Section 2, quarkonia suppressions in Section 3 and thermal photons in Section 4. A slightly longer and older version of this review can be found in [5]. Some updates are given here, as well as emphasis on new probes ...

  20. Interphase Death of Chinese Hamster Ovary Cells Exposed to Accelerated Heavy Ions

    Directory of Open Access Journals (Sweden)

    P. Mehnati

    2007-06-01

    Full Text Available Introduction: Heavy ions are nucleus of elements of iron, argon, carbon and neon that all carry positive electrical charges. For these particles to be useful in radiotherapy they need to accelerated to high energy by more than thousand mega volts. Also the cosmic environment is considered to be a complicated mixture of highly energetic photons and heavy ions such as iron. Therefore, the health risks to astronauts during long mission should be considered.  Materials and Methods: The induction of interphase death was tested on Chinese hamster ovary cells by exposing them to accelerated heavy ions (carbon, neon, argon and iron of 10-2000 linear energy transfers (LETs. The fraction of cells that underwent interphase death was determined by observing individual cells with time-lapse photography (direct method as well as by the indirect method of counting cells undergoing interphase death made visible by the addition of caffeine (indirect method. Results: The interphase death due to the exposure to X- rays is increased linearly as the dose exceeds the threshold dose of 10 Gy. Whereas the interphase death increases at a higher rate due to the exposure to high LET heavy ions and no threshold dose was observed. The range of LET values corresponding to the maximum RBE for the interphase death is 120-230 keV/µm. The probability of inducing the interphase death by a single heavy ion traversing through the nucleus is about 0.04-0.08. Discussion and Conclusion: The relative biological effectiveness (RBE of heavy ions as compared to X- rays as determined at the 50% level of induction is increased with LET. It reached a maximum value at a LET of approximately 230 keV/µm and then decreased with further increase in LET. The range of LET values corresponding to the maximum RBE appears to be narrower for interphase death than for reproductive death.

  1. Studies of the QCD Phase Diagram with Heavy-Ion Collisions at J-PARC

    Science.gov (United States)

    Sako, Hiroyuki

    To clarify phase structures in the QCD phase diagram is an ultimate goal of heavy-ion collision experiments. Studies of internal structures of neutron stars are also one of the most important topics of nuclear physics since the discovery of neutron stars with two-solar mass. For these physics goals, J-PARC heavy-ion project (J-PARC-HI) has been proposed, where extremely dense matter with 5-10 times the normal nuclear density will be created. Heavy-ion beams up to Uranium will be accelerated to 1-19 AGeV/c, with the designed world's highest beam rate of 1011 Hz. The acceleration of such high-rate beams can be realized by a new heavy-ion linac and a new booster ring, in addition to the existing 3-GeV and 50-GeV proton synchrotrons. To study the above physics goals, following physics observables will be measured in extremely high statistics expected in J-PARC-HI. To search for the critical point, high-order event-by-event fluctuations of conserved charges such as a net-baryon number, an electric charge number, and a strangeness number will be measured. To study the chiral symmetry restoration, dilepton spectra from light vector meson decays will be measured. Also, collective flows, particle correlations will be measured to study the equation of state and hyperon-hyperon and hyperon-nucleon interactions related to neutron stars. Strange quark matter (strangelet) and multi-strangeness hypernuclei will be searched for which may be related directly to the matter constituting the neutron star core. In this work, the physics goals, the experimental design, and expected physics results of J-PARC-HI will be discussed.

  2. Hard Probes in Heavy-Ion Physics

    CERN Document Server

    Renk, Thorsten

    2012-01-01

    The aim of ultrarelativistic heavy ion physics is to study collectivity and thermodynamics of Quantum Chromodynamics (QCD) by creating a transient small volume of matter with extreme density and temperature. There is experimental evidence that most of the particles created in such a collision form indeed a thermalized system characterized by collective response to pressure gradients. However, a numerically small subset of high transverse momentum ($P_T$) processes takes place independent of the bulk, with the outgoing partons subsequently propagating through the bulk medium. Understanding the modification of such 'hard probes' by the bulk medium is an important part of the efforts to determine the properties of hot and dense QCD matter. In this paper, current developments are reviewed.

  3. Relativistic heavy-ion physics: three lectures

    CERN Document Server

    McLerran, L

    2007-01-01

    These lectures provide an introduction to the physics issues which are being studied in the collisions of ultrarelativistic heavy ions. The lectures are focused on the production of new states of matter. The quark-gluon plasma is thermal matter which once existed in the Big Bang. The colour glass condensate is a universal form of high energy density gluonic matter which is part of a hadron wavefunction and which controls the high-energy limit of strong interactions. The glasma is matter produced in the collisons of high-energy hadrons which evolves into a quarkgluon plasma. The glasma has interesting topological properties and may be responsible for the early thermalization seen at RHIC. I introduce the student to these topics, discuss results from experiments, and comment upon future opportunities.

  4. Application of hydrodynamics to heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Felsberger, Lukas

    2014-12-02

    The Bjorken model is a simple tool for making rough predictions of the hydrodynamic evolution of the thermalized matter created in a heavy ion collision. The advantage of the model clearly lies in its simplicity, rather than accuracy. As it is still used for making rough estimations 'by hand', in this thesis, I investigate in which cases the Bjorken model gives useful results and in which it is not recommended. For central collisions, I show which critical size the nuclei should have so that the Bjorken model can be applied. For non-central collisions, I demonstrate that using Glauber initial conditions combined with the Bjorken evolution, leads to reasonable results up to large impact parameters. Finally, I study the case of a non-ideal (viscous) description of the thermalized matter which leads to strongly differing results if first- or second-order hydrodynamics is applied.

  5. Heavy Ion results from RHIC-BNL

    Directory of Open Access Journals (Sweden)

    Esumi Shinlchi

    2013-05-01

    Full Text Available Recent results from heavy ion collision experiments from RHIC at BNL are presented and discussed in terms of Quark Gluon Plasm properties, such as partonic collectivity and partonic energy loss. The experimental results with direct photons and heavy quarks have given important additional insights of the plasma on top of what has been known with light hadrons. Higher order event anisotropies and the related results have provided the geometrical, temporal and dynamical information of the plasma. The beam energy dependence of the various measurements could reveal the structure of QCD phase diagram and possibly the critical point in the diagram, where the properties of phase transition are expected to change drastically.

  6. Statistics of heavy-ion stopping

    CERN Document Server

    Glazov, L G; Schinner, A

    2002-01-01

    Energy-loss straggling of swift heavy ions penetrating through matter has been analysed on the basis of binary stopping theory as well as the modified Bohr model allowing for projectile screening. A program has been written which evaluates the generalized Bothe-Landau formula governing the energy-loss spectrum for penetration through a thin layer, allowing for charge exchange involving an arbitrary number of charge states. This program was generated on the basis of calculational schemes developed originally for swift light ions. Projectile screening and multiple-shell structure of target atoms are allowed for. Explicit energy-loss spectra are given for oxygen in carbon for charge states 6-8 and foil thickness 2, 10 and 50 mu g/cm sup 2. It is also demonstrated that frozen-charge straggling depends only weakly on charge state.

  7. Heavy ion Physics with the ATLAS Detector

    CERN Document Server

    White, S N

    2006-01-01

    Soon after the LHC is commissioned with proton beams the ATLAS experiment will begin studies of Pb-Pb collisions with a center of mass energy of ?sNN = 5.5 TeV. The ATLAS program is a natural extension of measurements at RHIC in a direction that exploits the higher LHC energies and the superb ATLAS calorimeter and tracking coverage. At LHC energies, collisions will be produced with even higher energy density than observed at RHIC. The properties of the resulting hot medium can be studied with higher energy probes, which are more directly interpreted through modification of jet properties emerging from these collisions, for example. Other topics which are enabled by the 30-fold increase in center of mass energy include probing the partonic structure of nuclei with hard photoproduction (in UltraPeripheral collisions) and in p-Pb collisions. Here we report on evaluation of ATLAS capabilities for Heavy Ion Physics.

  8. Electromagnetic probes in heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    van Hees H.

    2015-01-01

    Full Text Available Due to their penetrating nature, electromagnetic probes, i.e., lepton-antilepton pairs (dileptons and photons are unique tools to gain insight into the nature of the hot and dense medium of strongly-interacting particles created in relativistic heavy-ion collisions, including hints to the nature of the restoration of chiral symmetry of QCD. Of particular interest are the spectral properties of the electromagnetic current-correlation function of these particles within the dense and/or hot medium. The related theoretical investigations of the in-medium properties of the involved particles in both the partonic and hadronic part of the QCD phase diagram underline the importance of a proper understanding of the properties of various hadron resonances in the medium.

  9. From molecules to rainbows and Airy structures in light heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Haas, F.; Nicoli, M.P.; Freeman, R.M. [Inst. de Rech. Subatomiques, CNRS-IN2P3/ULP, Strasbourg (France); Szilner, S.; Basrak, Z. [Ruder Boskovic Institute HR-10 001 Zagreb (Croatia); Morsad, A. [Universite Hassan II, Casablanca (Morocco); Brandan, M.E. [Instituto de Fisica, UNAM (Mexico); Satchler, G.R. [University of Tennessee Knoxville and Oak Ridge National Laboratory (United States)

    2001-09-01

    Full text: Heavy ion interactions are usually dominated by strong absorption. This is not the case for certain light heavy ion collisions where the number of open channels is small and the absorption weak. Consequently, resonance phenomena are observed in these systems at bombarding energies lower than {approx} 5 MeV per nucleon. At higher energies, the weak absorption results in the observation of refractive effects which are very important to determine the nucleus-nucleus potential. In the present study, the refractive effects have been searched for in {sup 12} C + {sup 12} C, {sup 16} O + {sup 16} O, {sup 12} C + {sup 16} O and {sup 12} C + {sup 18} O reactions where the exit binary channels have been measured at several laboratory energies between 5 and 10 MeV per nucleon. The experiments have been performed at the Strasbourg Vivitron accelerator in the bombarding energy range where the reported experimental results are rather scarce. Detailed elastic scattering angular distributions up to large angles (crucial for the refractive effects) have been obtained. Their optical model analysis allowed to extract rather unique potentials which have strongly attractive real parts and relatively weakly absorbing imaginary parts. The energy and system dependence of the obtained potentials have been established. The elastic scattering angular distributions not only show the usual Fraunhofer diffraction pattern but also, at larger angles, refractive effects under the form of the nuclear rainbow Airy structures. For the systems studied, the existence and properties of the Airy minima will be discussed. (Author)

  10. Highlights from STAR heavy ion program

    Science.gov (United States)

    Okorokov, Vitalii

    2017-10-01

    Recent experimental results obtained in STAR experiment at the Relativistic heavy-ion collider (RHIC) with ion beams will be discussed. Investigations of different nuclear collisions in some recent years focus on two main tasks, namely, detail study of quark-gluon matter properties and exploration of the quantum chromodynamics (QCD) phase diagram. Results at top RHIC energy show clearly the collective behavior of heavy quarks in nucleus-nucleus interactions. Jet and heavy hadron measurements lead to new constraints for energy loss models for various flavors. Heavy-ion collisions are unique tool for the study of topological properties of theory as well as the magneto-hydrodynamics of strongly interacting matter. Experimental results obtained for discrete QCD symmetries at finite temperatures confirm indirectly the topologically non-trivial structure of QCD vacuum. Finite global vorticity observed in non-central Au+Au collisions can be considered as important signature for presence of various chiral effects in sQGP. Most results obtained during stage I of the RHIC beam energy scan (BES) program show smooth behavior vs initial energy. However certain results suggest the transition in the domain of dominance of hadronic degrees of freedom at center-of-mass energies between 10-20 GeV. The stage II of the BES at RHIC will occur in 2019-2020 and will explore with precision measurements in the domain of the QCD phase diagram with high baryon densities. Future developments and more precise studies of features of QCD phase diagram in the framework of stage II of RHIC BES will be briefly discussed.

  11. Mutagenic effect of accelerated heavy ions on bacterial cells

    Science.gov (United States)

    Boreyko, A. V.; Krasavin, E. A.

    2011-11-01

    The heavy ion accelerators of the Joint Institute for Nuclear Research were used to study the regularities and mechanisms of formation of different types of mutations in prokaryote cells. The induction of direct (lac-, ton B-, col B) mutations for Esherichia coli cells and reverse his- → His+ mutations of Salmonella typhimurium, Bacillus subtilis cells under the action of radiation in a wide range of linear energy transfer (LET) was studied. The regularities of formation of gene and structural (tonB trp-) mutations for Esherichia coli bacteria under the action of accelerated heavy ions were studied. It was demonstrated that the rate of gene mutations as a function of the dose under the action of Γ rays and accelerated heavy ions is described by linear-quadratic functions. For structural mutations, linear "dose-effect" dependences are typical. The quadratic character of mutagenesis dose curves is determined by the "interaction" of two independent "hitting" events in the course of SOS repair of genetic structures. The conclusion made was that gene mutations under the action of accelerated heavy ions are induced by δ electron regions of charged particle tracks. The methods of SOS chromotest, SOS lux test, and λ prophage induction were used to study the regularities of SOS response of cells under the action of radiations in a wide LET range. The following proposition was substantiated: the molecular basis for formation of gene mutations are cluster single-strand DNA breaks, and that for structural mutations, double-strand DNA breaks. It was found out that the LET dependence of the relative biological efficiency of accelerated ions is described by curves with a local maximum. It was demonstrated that the biological efficiency of ionizing radiations with different physical characteristics on cells with different genotype, estimated by the lethal action, induction of gene and deletion mutations, precision excision of transposons, is determined by the specific

  12. Basic atomic interactions of accelerated heavy ions in matter atomic interactions of heavy ions

    CERN Document Server

    Tolstikhina, Inga; Winckler, Nicolas; Shevelko, Viacheslav

    2018-01-01

    This book provides an overview of the recent experimental and theoretical results on interactions of heavy ions with gaseous, solid and plasma targets from the perspective of atomic physics. The topics discussed comprise stopping power, multiple-electron loss and capture processes, equilibrium and non-equilibrium charge-state fractions in penetration of fast ion beams through matter including relativistic domain. It also addresses mean charge-states and equilibrium target thickness in ion-beam penetrations, isotope effects in low-energy electron capture, lifetimes of heavy ion beams, semi-empirical formulae for effective cross sections. The book is intended for researchers and graduate students working in atomic, plasma and accelerator physics.

  13. Transport models for relativistic heavy-ion collisions at Relativistic ...

    Indian Academy of Sciences (India)

    2015-04-29

    Apr 29, 2015 ... Transport models for relativistic heavy-ion collisions at Relativistic Heavy Ion Collider and Large Hadron Collider. Subrata Pal. Volume 84 Issue 5 May 2015 pp ... Subrata Pal1. Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India ...

  14. Heavy ions at the LHC: Physics perspectives and experimental ...

    Indian Academy of Sciences (India)

    Abstract. Ultrarelativistic heavy ion physics is entering the new era of collider experiments with the start-up of RHIC at BNL and construction for detectors at LHC well under way. At this crossroads, the article will give a summary of the experimental program and our current view of heavy ion physics at the LHC, concentrating ...

  15. Heavy ions: Results from the Large Hadron Collider

    Indian Academy of Sciences (India)

    The LHC worked exceedingly well during its one month of operation with heavy ions, delivering about 10 −1 of data, with peak luminosity reaching to L O = 2 × 10 25 cm-2 s-1 towards the end of the run. Three experiments, ALICE, ATLAS and CMS, recorded their first heavy-ion data, which were analysed in a record time.

  16. Theoretical Concepts for Ultra-Relativistic Heavy Ion Collisions

    Energy Technology Data Exchange (ETDEWEB)

    McLerran,L.

    2009-07-27

    Various forms of matter may be produced in ultra-relativistic heavy ion collisions. These are the Quark GluonPlasma, the Color Glass Condensate , the Glasma and Quarkyoninc Matter. A novel effect that may beassociated with topological charge fluctuations is the Chiral Magnetic Effect. I explain these concepts andexplain how they may be seen in ultra-relatvistic heavy ion collisions

  17. Structural and electrical properties of swift heavy ion beam irradiated ...

    Indian Academy of Sciences (India)

    Synthesis of swift heavy ion induced metal silicide is a new advancement in materials science research. We have investigated the mixing at Co/Si interface by swift heavy ion beam induced irradiation in the electronic stopping power regime. Irradiations were undertaken at room temperature using 120 MeV Au ions at the ...

  18. Conceptual design of the Relativistic Heavy Ion Collider: RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Samios, Nicholas P.

    1986-05-01

    The complete Relativistic Heavy Ion Collider (RHIC) facility will be a complex set of accelerators and beam transfer equipment connecting them. A significant portion of the total facility either exists or is under construction. Two existing Tandem Van de Graaff accelerators will serve for the initial ion acceleration. Ions with a charge of -1 would be accelerated from ground to +15 MV potential, pass through a stripping foil, and accelerate back to ground potential, where they would pass through a second stripping foil. From there the ions will traverse a long transfer line to the AGS tunnel and be injected into the Booster accelerator. The Booster accelerates the ion bunch, and then the ions pass through one more stripper and then enter the Alternating Gradient Synchrotron (AGS), where they are accelerated to the top AGS energy and transferred to the collider. Bending and focusing of ion beams is to be achieved by superconducting magnets. The physics goals behind the RHIC are enumerated, particularly as regards the study of quark matter and the characteristics of high energy nucleus-nucleus collisions. The design of the collider and all its components is described, including the injector, the lattice, magnet system, cryogenic and vacuum systems, beam transfer, injection, and dump, rf system, and beam instrumentation and control system. Also given are cost estimates, construction schedules, and a management plan. (LEW)

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

    Directory of Open Access Journals (Sweden)

    R. Bruce

    2010-09-01

    Full Text Available 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 ^{197}Au^{79+} beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multiparticle 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 ^{208}Pb^{82+} beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

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

    Science.gov (United States)

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

    2010-09-01

    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 100GeV/nucleon Au79+197 beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multiparticle 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 Pb82+208 beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

  1. An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: Hard probes

    Directory of Open Access Journals (Sweden)

    Panagiota Foka

    2016-11-01

    Full Text Available The first collisions of lead nuclei, delivered by the CERN Large Hadron Collider (LHC at the end of 2010, at a centre-of-mass energy per nucleon pair sNN= 2.76 TeV, marked the beginning of a new era in ultra-relativistic heavy-ion physics. The study of the properties of the produced hot and dense strongly-interacting matter at these unprecedented energies is currently experimentally pursued by all four big LHC experiments, ALICE, ATLAS, CMS, and LHCb. The more than a factor 10 increase of collision energy at LHC, relative to the previously achieved maximal energy at other collider facilities, results in an increase of production rates of hard probes. This review presents selected experimental results focusing on observables probing hard processes in heavy-ion collisions delivered during the first three years of the LHC operation. It also presents the first results from Run 2 heavy-ion data at the highest energy, as well as from the studies of the reference pp and p–Pb systems, which are an integral part of the heavy-ion programme.

  2. The interaction between light heavy-ions and what it tells us

    Energy Technology Data Exchange (ETDEWEB)

    Brandan, M.E. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico). Inst. de Fisica; Satchler, G.R. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States)]|[Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6373 (United States)

    1997-06-01

    Significant progress has been achieved during the last decade in our knowledge and understanding of the optical potential between two light heavy-ions. This has mostly been a consequence of the measurement of accurate and extensive elastic differential cross sections. Some of these data, covering over eight orders of magnitude in cross section, extend to sufficiently large scattering angles that they show remarkable refractive effects which remind one of features of the scattering of alpha particles by nuclei that have been known since the work of Goldberg some twenty years ago. Refractive effects, particularly nuclear rainbows, are evident in {sup 12}C+{sup 12}C and {sup 16}O+{sup 16}O angular distributions at bombarding energies between 6 and 100 MeV per nucleon. Their angular location and cross section have led to the determination of the gross features of the local optical potentials and in many cases have removed ambiguities in the depths of the real parts of the potentials. The resulting phenomenological potentials are strongly attractive (``deep``), with relatively weak absorption, and depend upon the bombarding energy. The optical model potential for such heavy-ions is no longer simply a way to parameterize scattering data (or perhaps just one of many ways). Ambiguities have been resolved, and a good understanding of the theoretical basis of its features has been attained. The folding model is central to this understanding, coupled with increased insight into the nature of realistic effective nucleon-nucleon interactions. This Report reviews the experimental evidence, its interpretation, and what we have learnt from it. Much of the interpretation becomes especially transparent when couched in the language of semiclassical scattering theory. We summarize this language, as well as the basic features of the theory of the optical model. (orig.).

  3. Electromagnetic Radiations from Heavy Ion Collision

    Directory of Open Access Journals (Sweden)

    Payal Mohanty

    2013-01-01

    Full Text Available In this review, we have discussed the different sources of photons and dileptons produced in heavy ion collision (HIC. The transverse momentum (pT spectra of photons for different collision energies are analyzed with a view of extracting the thermal properties of the system formed in HIC. We showed the effect of viscosity on pT spectra of produced thermal photons. The dilepton productions from hot hadrons are considered including the spectral change of light vector mesons in the thermal bath. We have analyzed the pT and invariant mass (M spectra of dileptons for different collision energies too. As the individual spectra are constrained by certain unambiguous hydrodynamical inputs, so we evaluated the ratio of photon to dilepton spectra, Rem, to overcome those quantities. We argue that the variation of the radial velocity extracted from Rem with M is indicative of a phase transition from the initially produced partons to hadrons. In the calculations of interferometry involving dilepton pairs, it is argued that the nonmonotonic variation of HBT radii with invariant mass of the lepton pairs signals the formation of quark gluon plasma in HIC. Elliptic flow (v2 of dilepton is also studied at sNN=2.76 TeV for 30–40% centrality using the (2+1d hydrodynamical model.

  4. High current injector for heavy ion fusion

    Science.gov (United States)

    Yu, S.; Eylon, S.; Chupp, W. W.

    1993-05-01

    A 2 MV, 800 mA, K(+) injector for heavy ion fusion studies is under construction. This new injector is a one-beam version of the proposed 4-beam ILSE injector. A new 36-module MARX is being built to achieve a 5 micro-s flat top. The high voltage generator is stiff (less than 5k Omega) to minimize effects of beam-induced transients. A large (approximately 7 in. diameter) curved hot alumina-silicate source emits a 1 micro-s long beam pulse through a gridless extraction electrode, and the ions are accelerated to 1 MV in a diode configuration. Acceleration to 2 MV takes place in a set of electrostatic quadrupole (ESQ) units, arranged to simultaneously focus and accelerate the ion beam. Heavy shields and other protection devices have been built in to minimize risks of high voltage breakdown. Beam aberration effects through the ESQ have been studied extensively with theory, simulations, and scaled experiments. The design, simulations, experiments, and engineering of the ESQ injector will be presented.

  5. Inertially confined fusion using heavy ion drivers

    Energy Technology Data Exchange (ETDEWEB)

    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))

    1991-10-01

    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.

  6. Inertially confined fusion using heavy ion drivers

    Energy Technology Data Exchange (ETDEWEB)

    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)

    1991-10-01

    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.

  7. Heavy ion acceleration at parallel shocks

    Directory of Open Access Journals (Sweden)

    V. L. Galinsky

    2010-11-01

    Full Text Available A study of alpha particle acceleration at parallel shock due to an interaction with Alfvén waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model (Galinsky and Shevchenko, 2000, 2007. The model uses conservation laws and resonance conditions to find where waves will be generated or damped and hence where particles will be pitch-angle scattered. It considers the total distribution function (for the bulk plasma and high energy tail, so no standard assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles are required. The heavy ion scattering on hydromagnetic turbulence generated by both protons and ions themselves is considered. The contribution of alpha particles to turbulence generation is important because of their relatively large mass-loading parameter Pα=nαmα/npmp (mp, np and mα, nα are proton and alpha particle mass and density that defines efficiency of wave excitation. The energy spectra of alpha particles are found and compared with those obtained in test particle approximation.

  8. A radial TPC for heavy ions

    CERN Document Server

    Garabatos, C

    2000-01-01

    The CERES experiment at the CERN SPS has been recently upgraded with a TPC with radial drift field, the first one of its sort. Constructed during 1998, it has been successfully operated in commissioning and physics runs, with muon, proton, and heavy-ion beams. A high voltage electrode of about 0.5 m radius is surrounded by sixteen 2 m long readout chambers, placed at a radius of 1.3 m, with chevron-shaped readout pads. The field cage is enclosed by two low-mass voltage degraders at each end of the cylindrical structure. A Ne-CO/sub 2/ [80-20] gas mixture allows for a safe operation and good transport properties under drift fields ranging from 200 to 600 V/cm. A spatial resolution better than 700 microns and 350 microns in r and rdelta (phi), respectively, has been achieved in a highly inhomogeneous magnetic field. Details of its construction as well as results of the operation and performance in a high multiplicity environment are presented. (0 refs).

  9. CHICO, a heavy ion detector for Gammasphere

    CERN Document Server

    Simon, M W; Wu, C Y; Gray, R W; Teng, R; Long, C

    2000-01-01

    A 4 pi position-sensitive heavy-ion detector system, CHICO, has been developed primarily for use in conjunction with the 4 pi gamma-ray facility, Gammasphere. The CHICO detector comprises an array of 20 Parallel Plate Avalanche Counters (PPACs) covering 12 deg.

  10. Status of the relativistic heavy ion collider

    Energy Technology Data Exchange (ETDEWEB)

    Karl, F. [Brookhaven National Lab., Upton, NY (United States)

    1999-07-01

    At the present time, commissioning of the 3.8 kilometer Relativistic Heavy Ion Collider (RHIC) is in full swing. On July 16, 1999, the commissioners were successful in circulating a Gold Ion Beam for the first time, in the Blue Ring, as power supplies were being checked out for beam into the Yellow Ring. The commissioning schedule is to accelerate beam in the Blue Ring, then spiral and accelerate beam in the Yellow Ring, then if all goes well, obtain some collisions, all before a fast approaching shutdown in mid-August. The four experimental regions, Star, Phenix, Brahms and Phobos are gearing up for their maiden beam runs and much effort is being spent to make the thirst glimpse of the beam an exciting one. Our Alignment Group has been working closely with the experimenters in these areas, mostly with MANCAT type component pre-surveys and in the near future installing and locating these various components relative to the RHIC Beam Line. (author)

  11. The search for super-heavy ions

    CERN Document Server

    Grévy, S

    2003-01-01

    The present the search for heavy nuclei, they briefly draw a historical review of the production of heavy isotopes and then describe the means and possibilities the French GANIL (national great accelerator of heavy ions) facility offers. The different steps of the experimental process are described: production, selection, detection and identification. The production cross-sections are so weak that every parameter involved in the production process has to be optimized. It appears that the limit of our technological knowledge has been reached and unless an important technical step forward it seems impossible to go down below the pico-barn (10 sup - sup 1 sup 2 *10 sup - sup 2 sup 4 cm sup 2) for production cross-sections. The 2 remaining ways to improve the situation are: 1) to increase the intensity of the incident particle beam (today we have < 10 sup 1 sup 3 pps), this implies that an important development about accelerators and ion sources has to be achieved, 2) the other way is to use radioactive ion be...

  12. Heavy Ion physics in ATLAS and CMS

    CERN Document Server

    Kodolova, Olga

    2008-01-01

    We will present the capabilities of the ATLAS and CMS experiments to explore the heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies $\\sqrt{s_{_{NN}}}$ = 5.5 TeV, will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction (QCD) in extreme conditions of temperature, density and low parton momentum fraction. The current paper will give an overview of the potential of ATLAS and CMS to carry out a set of representative Pb-Pb measurements. These include ``bulk'' observables, like charged hadron multiplicity, low $p_{\\rm T}$ inclusive hadron identified spectra and elliptic flow -- which provide information on the collective properties of the system; as well as perturbative processes, such as quarkonia, heavy-quarks, jets, $\\gamma$-jet, and high $p_{\\rm T}$ hadrons --- which yield ``tomographic'' information of the hottest and densest phases...

  13. Reaction mechanisms in heavy ion fusion

    Directory of Open Access Journals (Sweden)

    Lubian J.

    2011-10-01

    Full Text Available We discuss the reaction mechanisms involved in heavy ion fusion. We begin with collisions of tightly bound systems, considering three energy regimes: energies above the Coulomb barrier, energies just below the barrier and deep sub-barrier energies. We show that channel coupling effects may influence the fusion process at above-barrier energies, increasing or reducing the cross section predicted by single barrier penetration model. Below the Coulomb barrier, it enhances the cross section, and this effect increases with the system’s size. It is argued that this behavior can be traced back to the increasing importance of Coulomb coupling with the charge of the collision partners. The sharp drop of the fusion cross section observed at deep sub-barrier energies is addressed and the theoretical approaches to this phenomenon are discussed. We then consider the reaction mechanisms involved in fusion reactions of weakly bound systems, paying particular attention to the calculations of complete and incomplete fusion available in the literature.

  14. Experimental review of quarkonium production in heavy-ion collisions

    Science.gov (United States)

    Zha, Wangmei; Tang, Zebo

    2017-08-01

    Quarkonium provides a sensitive probe to the properties of the quark-gluon plasma (QGP). Its production yield in heavy-ion collisions is modified by the color-screening effect, heavy quark (re)combination effect and cold nuclear matter effects. These effect have different sensitivity to various properties of the medium. Using quarkonium to experimentally study the properties of the QGP requires comprehensive measurements in heavy-ion collisions. In this article, we review the recent experimental measurements of different quarkonium states in heavy-ion collisions at the RHIC and the LHC.

  15. Imaging instrument for positron emitting heavy ion beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Llacer, J.; Chatterjee, A.; Jackson, H.C.; Lin, J.C.; Zunzunegui, M.V.

    1978-10-01

    The design and performance of an instrument for the imaging of coincidence annihilation gamma rays emitted from the end point of the trajectories of radioactive high-energy heavy ions is described. The positron-emitting heavy ions are the result of nuclear fragmentation of accelerated heavy ions used in cancer therapy or diagnostic medicine. The instrument constructed is capable of locating the ion beam trajectory end point within 1 mm for an injected activity of 200 nanoCi in a measurement time of 1 sec in some favorable conditions. Limited imaging in three dimensions is also demonstrated.

  16. Dynamic processes in heavy-ion collisions at intermediate energies

    Science.gov (United States)

    Prendergast, E. P.

    1999-03-01

    This thesis describes the study of the reaction dynamics in heavy-ion collisions of small nuclear systems at intermediate energies. For this, experiments were performed of 24Mg+27A1 at 45 and 95 AMeV. The experiments described in this thesis were performed at the GANIL accelerator facility in Caeri (France) using the Huygens detectors in conjunction with the ‘MUR’. The Huygens detectors consist of the CsI(Tl)-Wall (CIW) covering the backward hemisphere and, located at mid-rapidity, the central trigger detector (CTD), a gas chamber with microstrip read-out backed by 48 plastic scintillators. The forward region is covered by 16 of the plastic scintillators of the CTD and by the MUR, a time-of-flight wall consisting of 96 plastic scintillator sheets. In earlier experiments only fragments with atomic number, Z, greater then two could be identifled in the CTD. Therefore, an investigation was done into the properties of different drift gases. The use of freon (CF4) in the drift chamber, combined with an increase of the gas pressure to 150 mbar, makes it possible to identify all particles with Z ≥ 2. Under these conditions particles with Z = 1 can only be identifled to approximately 25 AMeV. The Isospin Quantum Molecular Dynamics (IQMD) model has been used, to interpret the measured data. This model gives a microscopical description of heavy-ion collisions and simulates collisions on an event by event basis. In IQMD all protons and neutrons are represented as individual Gaussian wave packets. After initialisation the path of each nucleon is calculated for 200 fm/c, after which the simulation is stopped. At this time, nucleons which are close in space are clustered into fragments. The events generated by IQMD can then be processed by a GEANT detector simulation. This calculation takes into account the effects of the detector on the incoming particles. By using the GEANT simulation it is possible to give a direct comparison between the results of IQMD and the

  17. Soft errors in 10-nm-scale magnetic tunnel junctions exposed to high-energy heavy-ion radiation

    Science.gov (United States)

    Kobayashi, Daisuke; Hirose, Kazuyuki; Makino, Takahiro; Onoda, Shinobu; Ohshima, Takeshi; Ikeda, Shoji; Sato, Hideo; Inocencio Enobio, Eli Christopher; Endoh, Tetsuo; Ohno, Hideo

    2017-08-01

    The influences of various types of high-energy heavy-ion radiation on 10-nm-scale CoFeB-MgO magnetic tunnel junctions with a perpendicular easy axis have been investigated. In addition to possible latent damage, which has already been pointed out in previous studies, high-energy heavy-ion bombardments demonstrated that the magnetic tunnel junctions may exhibit clear flips between their high- and low-resistance states designed for a digital bit 1 or 0. It was also demonstrated that flipped magnetic tunnel junctions still may provide proper memory functions such as read, write, and hold capabilities. These two findings proved that high-energy heavy ions can produce recoverable bit flips in magnetic tunnel junctions, i.e., soft errors. Data analyses suggested that the resistance flips stem from magnetization reversals of the ferromagnetic layers and that each of them is caused by a single strike of heavy ions. It was concurrently found that an ion strike does not always result in a flip, suggesting a stochastic process behind the flip. Experimental data also showed that the flip phenomenon is dependent on the device and heavy-ion characteristics. Among them, the diameter of the device and the linear energy transfer of the heavy ions were revealed as the key parameters. From their dependences, the physical mechanism behind the flip was discussed. It is likely that a 10-nm-scale ferromagnetic disk loses its magnetization due to a local temperature increase induced by a single strike of heavy ions; this demagnetization is followed by a cooling period associated with a possible stochastic recovery process. On the basis of this hypothesis, a simple analytical model was developed, and it was found that the model accounts for the results reasonably well. This model also predicted that magnetic tunnel junctions provide sufficiently high soft-error reliability for use in space, highlighting their advantage over their counterpart conventional semiconductor memories.

  18. Sample Management System for Heavy Ion Irradiation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A robotic sample management device and system for the exposure of biological and material specimens to heavy ion beams of the NASA Space Radiation Laboratory (NSRL)...

  19. Failure Analysis of Heavy-Ion-Irradiated Schottky Diodes

    Science.gov (United States)

    Casey, Megan C.; Lauenstein, Jean-Marie; Wilcox, Edward P.; Topper, Alyson D.; Campola, Michael J.; Label, Kenneth A.

    2017-01-01

    In this work, we use high- and low-magnitude optical microscope images, infrared camera images, and scanning electron microscope images to identify and describe the failure locations in heavy-ion-irradiated Schottky diodes.

  20. Silicon Carbide Power Device Performance Under Heavy-Ion Irradiation

    Science.gov (United States)

    Lauenstein, Jean-Marie; Casey, Megan; Topper, Alyson; Wilcox, Edward; Phan, Anthony; Ikpe, Stanley; LaBel, Ken

    2015-01-01

    Heavy-ion induced degradation and catastrophic failure data for SiC power MOSFETs and Schottky diodes are examined to provide insight into the challenge of single-event effect hardening of SiC power devices.

  1. Beam loss mechanisms in relativistic heavy-ion colliders

    CERN Document Server

    Bruce, Roderik; Gilardoni, S; Wallén, E

    2009-01-01

    The Large Hadron Collider (LHC), the largest particle accelerator ever built, is presently under commissioning at the European Organization for Nuclear Research (CERN). It will collide beams of protons, and later Pb82+ ions, at ultrarelativistic energies. Because of its unprecedented energy, the operation of the LHC with heavy ions will present beam physics challenges not encountered in previous colliders. Beam loss processes that are harmless in the presently largest operational heavy-ion collider, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, risk to cause quenches of superconducting magnets in the LHC. Interactions between colliding beams of ultrarelativistic heavy ions, or between beam ions and collimators, give rise to nuclear fragmentation. The resulting isotopes could have a charge-to-mass ratio different from the main beam and therefore follow dispersive orbits until they are lost. Depending on the machine conditions and the ion species, these losses could occur in loca...

  2. Background Effects on Jet Detection in Heavy Ion Collisions

    Science.gov (United States)

    Aukerman, Alexander; Hughes, Charles; Krobatch, Thomas; Matyja, Adam; Nattrass, Christine; Neuhas, James; Sorensen, Soren; Witt, Will

    2017-09-01

    Heavy ion collisions performed at the LHC and RHIC at large energy scales produce a liquid of quarks and gluons known as a Quark-Gluon Plasma (QGP). Jets, which are collimated bunches of particles emitted from highly energetic partons, are produced at the early stages of these collisions, and can provide information about the properties of the QGP. Partonic energy loss in the medium can by quantified by measurements of fragmentation functions. However, the high background energies resulting from emissions uncorrelated to the initial hard scatterings in the heavy ion collisions place limitations on jet detection methods and fragmentation measurements. For the purpose of investigating the limitations on these current jet detection methods we generated a heavy ion background based on charged hadron data. We explore the behavior of a jet finding algorithm with our generated background to examine how the presence of a heavy ion background may affect the measurements of jet properties.

  3. Gamma-ray spectroscopy with relativistic exotic heavy-ions

    Indian Academy of Sciences (India)

    Abstract. Feasibility of gamma-ray spectroscopy at relativistic energies with exotic heavy-ions and new generation of germanium detectors (segmented Clover) is discussed. An experiment with such detector array and radioactive is discussed.

  4. Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

    1976-01-01

    A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2/sup 0/K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (..delta..E/E approximately equal to 2 x 10/sup -4/) or very good time resolution (..delta.. t approximately equal to 30 psec).

  5. Residual activity induced by heavy ions and beam-loss criteria for heavy-ion accelerators

    Directory of Open Access Journals (Sweden)

    I. Strašík

    2010-07-01

    Full Text Available The paper presents results of FLUKA simulations of the residual activity induced by heavy ions in two target configurations representing: (1 a beam pipe of an accelerator and (2 a bulky accelerator structure like a magnet yoke or a coil. The target materials were stainless steel and copper representing the most common construction materials used for basic accelerator components. For these two materials, the inventory of the induced isotopes depends mainly on the target material and much less on the projectile species. Time evolution of the induced activity can be described by means of a generic curve that is independent from the projectile mass. Dependence of the induced residual activity on selected ion beam parameters was studied. The main goal of the study was establishing a scaling law expanding the existing proton beam-loss tolerance to heavy-ion beams. This scaling law enables specifying beam-loss criteria for projectile species from proton up to uranium at energies from 200  MeV/u up to 1  GeV/u.

  6. Heavy Ions at the LHC Physics Perspectives and Experimental Program

    CERN Document Server

    Schükraft, Jürgen

    2002-01-01

    Ultrarelativistic heavy ion physics is entering the new era of collider experiments with the start-up of RHIC at BNL and construction for detectors at HC well under way. At this crossroads, the article will give a summary of the experimental program and our current view of heavy ion physics at the LHC, concentrating in particular on physics topics that are different or unique compared to current facilities.

  7. Heavy-ion physics at high baryon densities

    Directory of Open Access Journals (Sweden)

    Friese Volker

    2015-01-01

    Full Text Available Currently, several experimental programmes, both at existing and at future accelerator facilities, aim at investigating strongly interacting matter with nuclear collisions at energies below top SPS energy. These activities complement the heavy-ion experiments conducted at the highest available energies at the RHIC and LHC accelerators. In this report, we discuss the motivation for and prospects of the low-energy heavy-ion programmes.

  8. Nuclear matter EoS including few-nucleon correlations

    Science.gov (United States)

    Röpke, G.

    2017-11-01

    Improving a mean-field approach to the nuclear matter equation of state (EoS), few-nucleon correlations are investigated. The contribution of clusters to the thermodynamic properties is suppressed at increasing density because of Pauli blocking. Continuum correlations are implemented. Applications to heavy-ion collisions (HIC) are discussed.

  9. Radiation Physics and Chemistry in Heavy-ion Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Kimura, M.

    2007-12-01

    Full Text Available Heavy ions, such as carbon and oxygen ions, are classified as high-LET radiations, and produce a characteristic dose-depth distribution different from that of low-LET radiations such as γ-rays, xrays and electrons. Heavy ions lose less energy at the entrance to an irradiated biological system up to some depth than the low-LET radiations, while they deposit a large amount of dose within a very narrow range at a certain depth, producing the characteristic sharp peak called the Bragg peak. Therefore, by controlling the Bragg peak, it becomes possible to irradiate only the tumor region in a pin-point manner, while avoiding irradiation of the normal tissue, thus making heavyion therapy ideal for deep-seated tumor treatment. Clinical results on more than 2400 patients are very encouraging. However, very little is known about what is going on in terms of physics and chemistry inside the Bragg peak. In this paper the current status of our understanding of heavy-ion interactions and remaining problems of physics and chemistry for the heavy-ion treatment are explored, particularly in the Bragg peak region. Specially, the survey of the basic physical quantity, the mean energy required to form an ion pair (Wvalue for heavy ions of interest for radiotherapy is presented. Finally, the current clinical status of heavy-ion therapy is presented.

  10. W Boson Production in Ultrarelativistic Heavy-Ion Collisions at the CERN LHC

    Science.gov (United States)

    Balestri, Thomas E.

    Ultrarelativistic heavy-ion collisions at the CERN Large Hadron Collider (LHC) are capable of producing a medium of deconfined quarks and gluons. This phase of nuclear matter is called a Quark-Gluon Plasma (QGP) and is believed to have been present during the first microseconds following the Big Bang. W bosons are a unique probe in a QGP since they do not carry color charge and thus do not interact with a strongly-coupled medium. Furthermore, the kinematics of W bosons are sensitive to the Bjorken momentum fraction x of partons within nucleons, and therefore W bosons may also be used to constrain parton distribution functions and to detect the presence of nuclear effects. This thesis presents the measurement of W boson production in the dense nuclear environment created in Pb+Pb collisions at a per nucleon pair center-of-mass energy squareroot of sNN = 2.76 TeV. The data for this measurement were collected with the ATLAS detector in 2011 and correspond to an integrated luminosity ƒ Ldt = 0.14 nb-1. The production of W bosons is detected using the W → munu mu decay channel, resulting in fiducial yields of 5487 +/-96 (stat.) +/-86(syst.) W+ → mu +numu events and 5262 +/-95 (stat.) +/-83(syst.) W- → mu- numu events. These results are combined with yields from the corresponding electron channel W → enue, and the combined measurement is used to construct the differential production yields and lepton charge asymmetry as a function of lepton absolute pseudorapidity. The integrated production yields and charge ratio as a function of the mean number of binary nucleon-nucleon collisions are also presented. The results are compared to predictions based on next-to-leading order QCD calculations. These observables can aid in better understanding nucleon structure within a heavy nucleus as well as provide insight into the mechanism of jet energy loss in a QGP.

  11. LET Estimation of Heavy Ion Particles based on a Timepix-Based Si Detector

    Science.gov (United States)

    Hoang, S.; Pinsky, L.; Vilalta, R.; Jakubek, J.

    2012-12-01

    Linear Energy Transfer (LET) is a measure of the energy transferred into a material as an ionizing particle passes through it. This quantity is useful in estimating the biological effects of ionizing radiation as expressed in dosimetric endpoints such as Dose-equivalent. Pixel detectors with silicon sensors -like the Medipix2 Collaboration's Timepix-based devices- are ideal instruments to measure the total energy deposited by a transiting ionizing particle. In this paper we propose an approach for determining the amount of LET from track images obtained with a Timepix-based Si pixel detector. In particular, we have developed a method to calculate the angle of incidence for a heavy ion particle as it passes through a 300 μm thick Si sensor layer based on an analysis of the information in the cluster of pixel hits. Using that angle information, the path length traversed by the particle can be computed, which then facilitates estimating the degree of LET. Results from experiments with data taken at the HIMAC (Heavy Ion Medical Accelerator) facility in Chiba, Japan, and NASA Space Radiation Laboratory at Brookhaven in USA, demonstrate the effectiveness and resolution of our method to determine the angle of incidence and LET of heavy ion particles.

  12. Broad-beam three-dimensional irradiation system for heavy-ion radiotherapy at HIMAC

    CERN Document Server

    Futami, Y; Fujita, M; Tomura, H; Higashi, A; Matsufuji, N; Miyahara, N; Endo, M; Kawachi, K

    1999-01-01

    A three-dimensional irradiation system using a broad beam has been installed for heavy-ion cancer therapy at the Heavy Ion Medical Accelerator in Chiba (HIMAC) facility. Only the target region is irradiated at the 100% dose level; the dose level at other parts of irradiated tissues is less, using a range shifter, a multileaf collimator and a compensator. The devices are the same as those used in two-dimensional irradiation, except that the setting values of the devices can be dynamically changed during the treatment. The thickness of the absorber and the aperture of the multileaf collimator are dynamically controlled during irradiation, so that the Bragg peak is swept in the depth direction and the Bragg peak outside of the target volume is blocked by the multileaf collimator. The performance of this system was checked by irradiation of a phantom using a 290 MeV/nucleon carbon beam. The dose distribution realized by this three-dimensional irradiation agreed satisfactorily with the planned one.

  13. Study of elementary transfer mechanisms during a collision between a swift multi-charged heavy ion and a neutral atom; Etude des mecanismes elementaires de transfert d`energie au cours d`une collision entre un ion lourd rapide multi-charge et un atome neutre

    Energy Technology Data Exchange (ETDEWEB)

    Jardin, P. [Caen Univ., 14 (France)

    1995-12-31

    This work is dedicated to the study of the energy transfer mechanisms which occur during a collision between a swift multicharged heavy ion and a neutral atom. The elementary energy energy transfer mechanisms (scattering, excitation, ionization, capture) and their consequences on the target velocity after the collision (recoil velocity) are recalled in the first chapter. In the case of small projectile diffusion angles, we show that the recoil velocity component, transverse to the incident projectile direction, results principally from the diffusion mechanism, while the longitudinal component is due essentially to the mass transfer and the inelastic energy transfer mechanisms. Since the target recoil velocities are very small, we have built an experimental set-up which reduces the impreciseness on their measurement due to the target thermal spread using, as targets, cooled atoms of a supersonic jet (temperature < 1 K). The association of time of flight and localisation techniques allows us, for each ionised target atom, to determine the three recoil velocity components with a very good accuracy (a few tens of meters per second). In chapter three, we describe the data analysis method. And then we present in the last chapter the results we have obtained for the collision systems Xe{sup 44+}(6.7 MeV/A) + Ar => Xe{sup 44} + Ar{sup q+}+qe{sup -} (q ranging from 1 to 7); Xe{sup 44+} (6.7 MeV/A) + He => Xe{sup 44+} He{sup 1+,2+}+1e{sup -},2e{sup -}. We show that it is possible to interpret the recoil velocity in terms of kinetic energy transferred to the target and to the electrons ejected from the target. (author) 44 refs.

  14. NF-kB activation and its downstream target genes expression after heavy ions exposure

    Science.gov (United States)

    Chishti, Arif Ali; Baumstark-Khan, Christa; Hellweg, Christine; Schmitz, Claudia; Koch, Kristina; Feles, Sebastian

    2016-07-01

    To enable long-term human space flight cellular radiation response to densely ionizing radiation needs to be better understood for developing appropriate countermeasures to mitigate acute effects and late radiation risks for the astronaut. The biological effectiveness of accelerated heavy ions (which constitute the most important radiation type in space) with high linear energy transfer (LET) for effecting DNA damage response pathways as a gateway to cell death or survival is of major concern not only for space missions but also for new regimes of tumor radiotherapy. In the current research study, the contribution of NF-κB in response to space-relevant radiation qualities was determined by a NF-κB reporter cell line (HEK-pNF-κB-d2EGFP/Neo L2). The NF-κB dependent reporter gene expression (d2EGFP) after ionizing radiation (X-rays and heavy ions) exposure was evaluated by flow cytometry. Because of differences in the extent of NF-κB activation after X-irradiation and heavy ions exposure, it was expected that radiation quality (LET) might play an important role in the cellular radiation response. In addition, the biological effectiveness (RBE) of NF-κB activation and reduction of cellular survival was examined for heavy ions having a broad range of LET (˜0.3 - 9674 keV/µm). Furthermore, the effect of LET on NF-κB target gene expression was analyzed by real time reverse transcriptase quantitative PCR (RT-qPCR). In this study it was proven that NF-κB activation and NF-κB dependent gene expression comprises an early step in cellular radiation response. Taken together, this study clearly demonstrates that NF-κB activation and NF-κB-dependent gene expression by heavy ions are highest in the LET range of ˜50-200 keV/μupm. The up-regulated chemokines and cytokines (CXCL1, CXCL2, CXCL10, IL-8 and TNF) might be important for cell-cell communication among hit as well as unhit cells (bystander effect). The results obtained suggest the NF-κB pathway to be a

  15. Inclusive reconstruction of hadron resonances in elementary and heavy-ion collisions with HADES

    Directory of Open Access Journals (Sweden)

    Kornakov Georgy

    2016-01-01

    Full Text Available The unambiguous identification of hadron modifications in hot and dense QCD matter is one of the important goals in nuclear physics. In the regime of 1 - 2 GeV kinetic energy per nucleon, HADES has measured rare and penetrating probes in elementary and heavy-ion collisions. The main creation mechanism of mesons is the excitation and decay of baryonic resonances throughout the fireball evolution. The reconstruction of shortlived (≈ 1 fm/c resonance states through their decay products is notoriously difficult. We have developed a new iterative algorithm, which builds the best hypothesis of signal and background by distortion of individual particle properties. This allows to extract signals with signal-to-background ratios of <1%.

  16. Chemical freeze-out in heavy ion collisions at large baryon densities

    CERN Document Server

    Floerchinger, Stefan

    2012-01-01

    We argue that the chemical freeze-out in heavy ion collisions at high baryon density is not associated to a phase transition or rapid crossover. We employ the linear nucleon-meson model with parameters fixed by the zero-temperature properties of nuclear matter close to the liquid-gas quantum phase transition. For the parameter region of interest this yields a reliable picture of the thermodynamic and chiral properties at non-zero temperature. The chemical freeze-out observed in low-energy experiments occurs when baryon densities fall below a critical value of about 15 percent of nuclear density. This region in the phase diagram is far away from any phase transition or rapid crossover.

  17. Dynamical deformation in heavy ion reactions and the characteristics of quasifission products

    Science.gov (United States)

    Guo, S. Q.; Gao, Y.; Li, J. Q.; Zhang, H. F.

    2017-10-01

    The investigation of the characteristics of low-energy heavy ion reactions covering both fusion and quasifission is carried out within the dinuclear system (DNS) concept, which is developed to include the deformation variables of fragments in addition to the mass numbers of the fragments, so that the energy dissipation, nucleon exchange, and deformation evolutions of the colliding nuclei as well as their correlations are treated simultaneously, and the potential energy surface of the system is thus reaction-time dependent. The direct consequence of introducing the deformation of fragments as dynamical variables is that one must treat the orientation between the two deformed nuclei. This is solved by introducing a barrier function. It is found that the model can reproduce data about the mass, as well as the total kinetic energy and its dispersion, of the reaction products very well, revealing that the DNS model has a reasonable theoretical foundation and thus can reliably describe the reaction mechanism.

  18. Universal trend for heavy-ion total reaction cross sections at energies above the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O.A.P.; Medeiros, E.L., E-mail: emil@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Morcelle, V. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2010-06-15

    Heavy-ion total reaction cross section measurements for more than one thousand one hundred reaction cases covering 61 target nuclei in the range {sup 6}Li-{sup 238}U, and 158 projectile nuclei from {sup 2}H up to {sup 84}Kr (mostly exotic ones) have been analysed in a systematic way by using an empirical, three-parameter formula which is applicable to cases for projectile kinetic energies above the Coulomb barrier. The analysis has shown that the average total nuclear binding energy per nucleon of the interacting nuclei and their radii are the chief quantities which describe the cross section patterns. A great number of cross section data (87%) has been quite satisfactorily reproduced by the proposed formula, therefore total reaction cross section predictions for new, not yet experimentally investigated reaction cases can be obtained within 25 percent (or much less) of uncertainty (author)

  19. Recent Improvements of Particle and Heavy Ion Transport code System: PHITS

    Science.gov (United States)

    Sato, Tatsuhiko; Niita, Koji; Iwamoto, Yosuke; Hashimoto, Shintaro; Ogawa, Tatsuhiko; Furuta, Takuya; Abe, Shin-ichiro; Kai, Takeshi; Matsuda, Norihiro; Okumura, Keisuke; Kai, Tetsuya; Iwase, Hiroshi; Sihver, Lembit

    2017-09-01

    The Particle and Heavy Ion Transport code System, PHITS, has been developed under the collaboration of several research institutes in Japan and Europe. This system can simulate the transport of most particles with energy levels up to 1 TeV (per nucleon for ion) using different nuclear reaction models and data libraries. More than 2,500 registered researchers and technicians have used this system for various applications such as accelerator design, radiation shielding and protection, medical physics, and space- and geo-sciences. This paper summarizes the physics models and functions recently implemented in PHITS, between versions 2.52 and 2.88, especially those related to source generation useful for simulating brachytherapy and internal exposures of radioisotopes.

  20. Ultra-peripheral heavy-ion collisions with the CMS experiment

    Science.gov (United States)

    2017-04-01

    Ultraperipheral collisions (UPCs) of heavy ions involve long range electromagnetic interactions at impact parameters larger than sum of their radii where hadronic interaction is largely suppressed and the exchanged photon materializes into qq(bar) bound state after interacting with the gluonic field of the target proton or ion. Photoproduction of heavy vector mesons (J/psi, Upsilon) thus provide direct information on the gluon distribution functions in the nucleon/nucleus at very low values of Bjorken-x. The CMS experiment has excellent capabilities for the measurement of the heavy vector mesons in the dimuon decay channel using the tracker and the muon chambers. The measured coherent J/psi photoproduction cross section in ultraperipheral Pb-Pb collisions using 2011 PbPb data and Upsilon photoproduction in ultraperipheral pPb collisions during 2013, will be presented. The prospects for future measurements using the data collected in the 2015 PbPb run will also be described.

  1. A review on recent light particle correlation data from heavy ion collisions at intermediate and low energies

    Energy Technology Data Exchange (ETDEWEB)

    Ardouin, D.

    1996-12-31

    A review of recent two-particle interferometry data for heavy-ion collisions in the domain of energy between ten and a few hundreds of MeV/nucleon is presented. Not only identical particles but unlike particle correlations have been used successfully as a probe for space-time dynamics of the collision process. Due to the availability of new dedicated charged particles or photon multi-detectors, the field of particle interferometry is moving to a good level of quantitative description: excitation energy and impact parameter dependences are now provided which should stimulate additional theoretical calculations for two-particle cross sections and emission of light fragments. (author). 102 refs.

  2. Impact parameter dependence of pion ratio in probing the nuclear symmetry energy using heavy-ion collisions

    OpenAIRE

    Wei, Gao-Feng; He, Guo-Qiang; Cao, Xin-Wei; Lu, Yi-Xin

    2016-01-01

    The impact parameter dependence of \\rpi ratio is examined in heavy-ion collisions at 400MeV/nucleon within a transport model. It is shown that the sensitivity of \\rpi ratio on symmetry energy shows a transition from central to peripheral collisions, i.e., the stiffer symmetry energy leads to a larger \\rpi ratio in peripheral collisions while the softer symmetry energy always leads this ratio to be larger in central collisions. After checking the kinematic energy distribution of \\rpi ratio, we...

  3. Track Reconstruction in Heavy Ion Events using the CMS Tracker

    CERN Document Server

    Roland, Christof

    2006-01-01

    The Large Hadron Collider at CERN will collide protons at sqrt{S}=14 TeV and lead ions at sqrt{S_{NN} =5.5 TeV. The study of heavy ion collisions is an integral part of the physics program of the Compact Muon Solenoid (CMS). Central heavy ion events at LHC energies are expected to produce a multiplicity of 1500 to 4000 charged particles per unit of rapidity. The CMS detector features a large acceptance and high resolution silicon tracker consisting of pixel and strip detector layers. In this note the algorithms used for pattern recognition in the very high track density environment of heavy ion collisions will be described. Detailed studies using the full detector simulation and reconstruction are presented and achieved reconstruction efficiencies, fake rates and resolutions are discussed.

  4. Ultrarelativistic heavy ion collisions: the first billion seconds

    Energy Technology Data Exchange (ETDEWEB)

    Baym, Gordon

    2016-12-15

    I first review the early history of the ultrarelativistic heavy ion program, starting with the 1974 Bear Mountain Workshop, and the 1983 Aurora meeting of the U.S. Nuclear Science Committtee, just one billion seconds ago, which laid out the initial science goals of an ultrarelativistic collider. The primary goal, to discover the properties of nuclear matter at the highest energy densities, included finding new states of matter – the quark-gluon plasma primarily – and to use collisions to open a new window on related problems of matter in cosmology, neutron stars, supernovae, and elsewhere. To bring out how the study of heavy ions and hot, dense matter in QCD has been fulfilling these goals, I concentrate on a few topics, the phase diagram of matter in QCD, and connections of heavy ion physics to cold atoms, cosmology, and neutron stars.

  5. Antiradiation vaccine: Technology and development of prophylaxis, prevention and treatment of biological consequences from Heavy Ion irradiation.

    Science.gov (United States)

    Popov, Dmitri; Maliev, Vecheslav

    Introduction: An anti-radiation vaccine could be an important part of a countermeasures reg-imen for effective radioprotection, immunoprophylaxis and immunotherapy of the acute radi-ation syndromes (ARS) after gamma-irradiation, neutron irradiation or heavy ion irradiation. Reliable protection of non-neoplastic regions of patients with different forms of cancer which undergo to heavy ion therapy ( e.g. Hadron-therapy) can significantly extend the efficiency of the therapeutic course. The protection of cosmonauts astronauts from the heavy ion ra-diation component of space radiation with specific immunoprophylaxis by the anti-radiation vaccine may be an important part of medical management for long term space missions. Meth-ods and experiments: 1. The Antiradiation Vaccine preparation -standard (mixture of toxoid form of Radiation Toxins -SRD-group) which include Cerebrovascular RT Neurotoxin, Car-diovascular RT Neurotoxin, Gastrointestinal RT Neurotoxin, Hematopoietic RT Hematotoxin. Radiation Toxins Specific Radiation Determinant Group were isolated from a central lymph of gamma-irradiated animals with Cerebrovascular, Cardiovascular, Gastrointestiinal, Hematopoi-etic forms of ARS. Devices for γ-radiation are "Panorama", "Puma". 2. Heavy ion exposure was accomplished at Department of Scientific Research Institute of Nuclear Physics, Dubna, Russia. The heavy ions irradiation was generated in heavy ion (Fe56) accelerator -UTI. Heavy Ion linear transfer energy -2000-2600 KeV mkm, 600 MeV U. Absorbed Dose -3820 Rad. 3. Experimental Design: Rabbits from all groups were irradiated by heavy ion accelerator. Group A -control -10 rabbits; Group B -placebo -5 rabbits; Group C -radioprotectant Cystamine (50 mg kg)-5 rabbits, 15 minutes before irradiation -5 rabbits; Group D -radioprotectant Gammafos (Amifostine -400mg kg ), -5 rabbits; Group E -Antiradiation Vaccine: subcuta-neus administration or IM -2 ml of active substance, 14 days before irradiation -5 rabbits. 4

  6. Clinical trial of cancer therapy with heavy ions at heavy ion research facility in lanzhou

    Science.gov (United States)

    Zhang, Hong

    With collaborative efforts of scientists from the Institute of Modern Physics (IMP), Chinese Academy of Sciences and hospitals in Gansu, initial clinical trial on cancer therapy with heavy ions has been successfully carried out in China. From November 2006 to December 2007, 51 patients with superficially-placed tumors were treated with carbon ions at Heavy Ion Research Facility in Lanzhou (HIRFL) within four beam time blocks of 6-11 days, collaborating with the General Hospital of Lanzhou Command and the Tumor Hospital of Gansu Province. Patients and Methods: There were 51 patients (31 males and 20 females) with superficially-placed tumors (squamous cell carcinoma of the skin, basal cell carcinoma of the skin, malignant skin melanoma, sarcoma, lymphoma, breast cancer, metastatic lymph nodes of carcinomas and other skin lesions). The tumors were less than 2.1 cm deep to the skin surface. All patients had histological confirmation of their tumors. Karnofsky Performance Scale (KPS) of all patients was more than 70. The majority of patients were with failures or recurrences of conventional therapies. Median age at the time of radiotherapy (RT) was 55.5 years (range 5-85 years). Patients were immobilized with a vacuum cushion or a head mask and irradiated by carbon ion beams with energy 80-100 MeV/u at spread-out Bragg peak field generated from HIRFL, with two and three-dimensional conformal irradiation methods. Target volume was defined by physical palpation [ultrasonography and Computerized tomography (CT), for some cases]. The clinical target volume (CTV) was defined as the gross total volume GTV with a 0.5-1.0cm margin axially. Field placement for radiation treatment planning was done based on the surface markings. RBE of 2.5-3 within the target volume, and 40-75 GyE with a weekly fractionation of 7 × 3-15 GyE/fraction were used in the trial. Patients had follow-up examinations performed 1 month after treatment, in 1 or 2 months for the first 6 months, and 3

  7. Preequilibrium particle emissions and in-medium effects on the pion production in heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Zhao-Qing [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

    2017-02-15

    Within the framework of the Lanzhou quantum molecular dynamics (LQMD) transport model, pion dynamics in heavy-ion collisions near threshold energies and the emission of preequilibrium particles (nucleons and light complex fragments) have been investigated. A density, momentum and isospin-dependent pion-nucleon potential based on the Δ-hole model is implemented in the transport approach, which slightly leads to the increase of the π{sup -}/π{sup +} ratio, but reduces the total pion yields. It is found that a bump structure of the π{sup -}/π{sup +} ratio in the kinetic energy spectra appears at the pion energy close to the Δ(1232) resonance region. The yield ratios of neutrons to protons from the squeeze-out particles perpendicular to the reaction plane are sensitive to the stiffness of nuclear symmetry energy, in particular at the high-momentum (kinetic energy) tails. (orig.)

  8. Quark vs Gluon jets in Heavy Ion Collisions

    CERN Document Server

    Drauksas, Simonas

    2017-01-01

    The project concerned quark and gluon jets which are often used as probes of Quantum Chromodynamics(QCD) matter created in nuclear collisions at collider energies. The goal is to look for differences between quark and gluon jets, study their substructure, look for distinguishing features in unquenched (pp collisions) and quenched (heavy ion collisions) jets by using multi-variate analysis which was carried out with the help of ROOT's \\href{https://root.cern.ch/tmva}{TMVA} tool. Mapping out the modification of jets due to medium interactions could give valuable input to constraining the time evolution of the Quark Gluon Plasma created in heavy ion collisions.

  9. Laser ion source for isobaric heavy ion collider experiment.

    Science.gov (United States)

    Kanesue, T; Kumaki, M; Ikeda, S; Okamura, M

    2016-02-01

    Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is (96)Ru + (96)Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

  10. Heavy ion observation with MIDORI satellite: trapped ACR

    CERN Document Server

    Kohno, T; Yamagiwa, I; Kato, C; Goka, T; Matsumoto, H

    1999-01-01

    The Heavy Ion Telescope (HIT) on board the Japanese earth observation satellite MIDORI (ADEOS) has observed energetic heavy ions at the circular sun-synchronous orbit with an altitude of 800 km and an inclination of 98 deg. . Geomagnetically trapped oxygen and nitrogen at L=2 are clearly observed which is similar to the results of SAMPEX. Their geographical distribution at a long belt from the southern tip of South America to that of Africa is also very close to the SAMPEX observation. The adiabaticity parameter epsilon sub m sub a sub x can be deduced as <=0.1.

  11. On the probability of cure for heavy-ion radiotherapy.

    Science.gov (United States)

    Hanin, Leonid; Zaider, Marco

    2014-07-21

    The probability of a cure in radiation therapy (RT)-viewed as the probability of eventual extinction of all cancer cells-is unobservable, and the only way to compute it is through modeling the dynamics of cancer cell population during and post-treatment. The conundrum at the heart of biophysical models aimed at such prospective calculations is the absence of information on the initial size of the subpopulation of clonogenic cancer cells (also called stem-like cancer cells), that largely determines the outcome of RT, both in an individual and population settings. Other relevant parameters (e.g. potential doubling time, cell loss factor and survival probability as a function of dose) are, at least in principle, amenable to empirical determination. In this article we demonstrate that, for heavy-ion RT, microdosimetric considerations (justifiably ignored in conventional RT) combined with an expression for the clone extinction probability obtained from a mechanistic model of radiation cell survival lead to useful upper bounds on the size of the pre-treatment population of clonogenic cancer cells as well as upper and lower bounds on the cure probability. The main practical impact of these limiting values is the ability to make predictions about the probability of a cure for a given population of patients treated to newer, still unexplored treatment modalities from the empirically determined probability of a cure for the same or similar population resulting from conventional low linear energy transfer (typically photon/electron) RT. We also propose that the current trend to deliver a lower total dose in a smaller number of fractions with larger-than-conventional doses per fraction has physical limits that must be understood before embarking on a particular treatment schedule.

  12. New Development on Modelling Fluctuations and Fragmentation in Heavy-Ion Collisions

    Science.gov (United States)

    Lin, Hao; Danielewicz, Pawel

    2017-09-01

    During heavy-ion collisions (HIC), colliding nuclei form an excited composite system. Instabilities present in the system may deform the shape of the system exotically, leading to a break-up into fragments. Many experimental efforts have been devoted to the nuclear multifragmentation phenomenon, while traditional HIC models, lacking in proper treatment of fluctuations, fall short in explaining it. In view of this, we are developing a new model to implement realistic fluctuations into transport simulation. The new model is motivated by the Brownian motion description of colliding particles. The effects of two-body collisions are recast in one-body diffusion processes. Vastly different dynamical paths are sampled by solving Langevin equations in momentum space. It is the stochastic sampling of dynamical paths that leads to a wide spread of exit channels. In addition, the nucleon degree of freedom is used to enhance the fluctuations. The model has been tested in reactions such as 112Sn + 112Sn and 58Ni + 58Ni, where reasonable results are yielded. An exploratory comparison on the 112Sn + 112Sn reaction at 50 MeV/nucleon with two other models, the stochastic mean-field (SMF) and the antisymmetrized molecular dynamics (AMD) models, has also been conducted. Work supported by the NSF Grant No. PHY-1403906.

  13. Multiple sampling ionization chamber (MUSIC) for measuring the charge of relativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Christie, W.B.; Romero, J.L.; Brady, F.P.; Tull, C.E.; Castaneda, C.M.; Barasch, E.F.; Webb, M.L.; Drummond, J.R.; Crawford, H.J.; Flores, I.

    1987-04-01

    A large area (1 m x 2 m) multiple sampling ionization chamber (MUSIC) has been constructed and tested. The MUSIC detector makes multiple measurements of energy 'loss', dE/dx, for a relativistic heavy ion. Given the velocity, the charge of the ion can be extracted from the energy loss distributions. The widths of the distributions we observe are much narrower than predicted by Vavilov's theory for energy loss while agreeing well with the theory of Badhwar which deals with the energy deposited. The versatile design of MUSIC allows a variety of anode configurations which results in a large dynamic range of charge. In our tests to date we have observed charge resolutions of 0.25e fwhm for 727 MeV/nucleon /sup 40/Ar and 0.30e fwhm for 1.08 GeV/nucleon /sup 139/La and /sup 139/La fragments. Vertical position and multiple track determination are obtained by using time projection chamber electronics. Preliminary tests indicate that the position resolution is also very good with sigmaapprox. =100 ..mu..m.

  14. $W$ boson production in ultrarelativistic heavy-ion collisions at the CERN LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00356981

    Ultrarelativistic heavy-ion collisions at the CERN Large Hadron Collider (LHC) are capable of producing a medium of deconfined quarks and gluons. This phase of nuclear matter is called a Quark-Gluon Plasma (QGP) and is believed to have been present during the first microseconds following the Big Bang. $\\Wboson$ bosons are a unique probe in a QGP since they do not carry color charge and thus do not interact with a strongly-coupled medium. Furthermore, the kinematics of $\\Wboson$ bosons are sensitive to the Bjorken momentum fraction $x$ of partons within nucleons, and therefore $\\Wboson$ bosons may also be used to constrain parton distribution functions and to detect the presence of nuclear effects. This thesis presents the measurement of $\\Wboson$ boson production in the dense nuclear environment created in $\\PbPb$ collisions at a per nucleon pair center-of-mass energy $\\sqrt{s_{\\mathrm{NN}}}=2.76\\TeV$. The data for this measurement were collected with the ATLAS detector in 2011 and correspond to a...

  15. Intermediate energies heavy ion collisions : study of the charged particles emission dynamics and emitters characterization; Collisions d`ions lourds aux energies intermediaires: etude de la dynamique d`emission des particules chargees et caracterisation des emetteurs

    Energy Technology Data Exchange (ETDEWEB)

    Bauge, E.

    1994-07-01

    In heavy ion collisions at intermediate energies, reaction processes are ranging from slow processes where equilibrium is achieved between every emission, up to direct processes where nucleon nucleon scattering and phase space availability are the deciding factors. In order to investigate this transition, both the emission dynamics and the characteristics of the emitter have been studied, both theoretically and experimentally in the AMPHORA detector, for the systems 7, 17, 27 and 34 AMeV, {sup 40}Ar+Al, {sup 40}Ar+Cu and {sup 40}Ar+Ag. First, the linear momentum transfer of the most central collisions has been evaluated for these systems, by measuring the velocity of heavy residues. Then, by measuring azimuthal angle correlations functions, and by comparing them with statistical model predictions, the average angular momentum of the emitter has been evaluated. To study the charged particles emission dynamics, experimental azimuthal angle and relative momentum correlation functions have been compared with simulations based on a classical trajectory model. Finally, predictions of an advanced BUU model have been studied for the system 34 AMeV 40 Ar+Al. (authors). 69 refs., 52 figs., 5 tabs.

  16. Photoluminescence and Raman studies in swift heavy ion irradiated ...

    Indian Academy of Sciences (India)

    Photoluminescence and Raman studies in swift heavy ion irradiated polycrystalline aluminum oxide ... Polymers Volume 32 Issue 5 October 2009 pp 515-519 ... A broad photoluminescence (PL) emission with peak at ∼447 nm and two sharp emissions with peak at ∼ 679 and ∼ 695 nm are observed in pristine when ...

  17. Quark-gluon plasma: Status of heavy ion physics

    Indian Academy of Sciences (India)

    produce such energy densities, thereby providing us a chance to test the above prediction. After a brief introduction of the .... bone of the analyses seeking to extract information from the data on whether QGP did form in the heavy ion ..... A similar exercise for S+Au or Pb+Au reveals an enhancement in the low mass region ...

  18. Theory of heavy ion collision physics in hadron therapy

    CERN Document Server

    2013-01-01

    Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine.

  19. Heavy ion accelerator and associated developments in India

    Indian Academy of Sciences (India)

    c Indian Academy of Sciences. Vol. 59, No. 5. — journal of. November 2002 physics pp. 703–712. Heavy ion accelerator and associated developments in India. G K MEHTA. University of Allahabad, Allahabad 211 002, India. Abstract. Developments of ion accelerator and associated facilities in India are presented. Various.

  20. Transport models for relativistic heavy-ion collisions at Relativistic ...

    Indian Academy of Sciences (India)

    Abstract. We review the transport models that are widely used to study the properties of the quark-gluon plasma formed in relativistic heavy-ion collisions at RHIC and LHC. We show that transport model analysis of two important and complementary observables, the anisotropic flow of bulk hadrons and suppression of ...

  1. What have we learned from relativistic heavy-ion collider?

    Indian Academy of Sciences (India)

    What do we hope and expect to learn in the future? 1. Introduction. The goal of the heavy ion program at the RHIC at Brookhaven National Laboratory is to make and study new forms of matter at energy densities in excess of ten times that of nuclear matter. I will describe the status of this program from a theorist's perspective.

  2. Recent studies in heavy ion induced fission reactions

    Indian Academy of Sciences (India)

    channel spins. Recently studies have been carried out on the spin distributions of fission fragments through the gamma ray multiplicity measurements. ... Heavy ion fission; angular distributions; fragment spin; mass; energy. ... neutrons and protons (magic numbers), and also resulting in deformed ground state shapes.

  3. Systematics of elliptic flow in heavy-ion collisions

    Indian Academy of Sciences (India)

    The main goal of ultra-relativistic heavy-ion collisions is to understand the behavior of. QCD under extreme ... collective motion of particles are called as flow and are identified as radial, sideward and elliptic flow. ... expands it becomes more spherical, quenching the driving force that produces the elliptic flow. The elliptic flow ...

  4. What have we learned from relativistic heavy-ion collider?

    Indian Academy of Sciences (India)

    In this talk, I present what I believe we have learned from the recent RHIC heavy ion experiments. The goal of these experiments is to make and study matter at very high energy densities, greater than an order of magnitude larger than that of nuclear matter. Have we made such matter? What have we learned about the ...

  5. Hydrodynamic modelling for relativistic heavy-ion collisions at RHIC ...

    Indian Academy of Sciences (India)

    Nz. 1. Introduction. The quark gluon plasma (QGP) is formed in high-energy heavy-ion collisions at Relativis- .... To obtain final hadrons, pure hydrodynamic simulations assume free hadron resonances directly emitted ... models is realized by a Monte-Carlo event generator, which transforms the hydrody- namic output into ...

  6. Response of silicon position sensitive detectors to heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Read, P.M.; Rotberg, V.H. (UKAEA Atomic Energy Research Establishment, Harwell. Nuclear Physics Div.); Tolfree, D.W.L.; Groves, J. (Science Research Council, Daresbury (UK). Daresbury Lab.)

    1983-01-15

    The pulse height response characteristics of surface barrier and ion implanted position sensitive detectors have been measured. Surface barrier detectors with junctions formed using oxidation by potassium dichromate exhibit small heavy ion pulse height defects indicating thin entrance windows. Ion implanted detectors give considerably larger defects because of penetrating tails in the distribution of implanted ions and electrically active defects.

  7. The response of silicon position sensitive detectors to heavy ions

    Science.gov (United States)

    Read, P. M.; Rotberg, V. H.; Tolfree, D. W. L.; Groves, J.

    1983-01-01

    The pulse height response characteristics of surface barrier and ion implanted position sensitive detectors have been measured. Surface barrier detectors with junctions formed using oxidation by potassium dichromate exhibit small heavy ion pulse height defects indicating thin entrance windows. Ion implanted detectors give considerably larger defects because of penetrating tails in the distribution of implanted ions and electrically active defects.

  8. Elastic recoil detection (ERD) with extremely heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Forster, J.S. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Currie, P.J. [Royal Tyrrell Museum, Drumheller, Alberta T0J 0Y0 (Canada); Davies, J.A. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Siegele, R. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Wallace, S.G. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Zelenitsky, D. [Department of Geology and Geophysics, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

    1996-06-01

    Extremely heavy-ion beams such as {sup 209}Bi in elastic recoil detection (ERD) make ERD a uniquely valuable technique for thin-film analysis of elements with mass {<=}100. We report ERD measurements of compositional analysis of dinosaur eggshells and bones. We also show the capability of the ERD technique on studies of thin-film, high-temperature superconductors. (orig.).

  9. Electron cloud studies for heavy-ion and proton machines

    CERN Document Server

    Petrov, F; Weiland, Th

    2013-01-01

    Electron cloud effects are a known problem in various accelerator facilities around the world. Electron clouds cause instabilities and emittance growth in positron and proton beams as well as in heavy ion beams. Most of the hadron machines experience the build-up of EC due to the multipacting. In LHC and in positron machines production of electrons due to the synchrotron radiation becomes as important as the build-up due to the secondary emission. The main source of seed electrons in heavy ion machines is the residual gas ionization. FAIR facility in Darmstadt will operate with heavy-ion and proton beams. However, the beam parameters are such that the multipacting will start to play a role only for the unconditioned wall with the secondary emission yieldmore than 1.8. In this paperwe study the electron cloud build-up and its effect on the beam stability for FAIR heavy-ion coasting beams. These beams will be used during slow extraction. Electron scattering on the beam ions and its effect on the final neutraliz...

  10. Quarkonia at finite temperature in relativistic heavy-ion collisions

    Indian Academy of Sciences (India)

    2015-05-06

    May 6, 2015 ... ... is reviewed. After a detailed discussion of the current theoretical understanding of quarkonia in a static equilibriated plasma, we discuss quarkonia yield from the fireball created in ultrarelativistic heavy-ion collision experiments. We end with a brief discussion of the experimental results and outlook.

  11. From Heavy-Ion Collisions to Quark Matter course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    Overview of the experimental activity going on at CERN (SPS and LHC) and at RHIC in view of the understanding of the properties of QCD matter (quark gluon plasma) at high temperatures and densities, through the study of heavy-ion collisions at very high energies.

  12. Structural and electrical properties of swift heavy ion beam irradiated ...

    Indian Academy of Sciences (India)

    Unknown

    search. We have investigated the mixing at Co/Si interface by swift heavy ion beam induced irradiation in the ... films are often employed in semiconductor technology and are used as ... rements at Co/Si interface were carried out online in the.

  13. HARD PHOTON INTENSITY INTERFEROMETRY IN HEAVY-ION REACTIONS

    NARCIS (Netherlands)

    OSTENDORF, R; SCHUTZ, Y; MERROUCH, R; LEFEVRE, F; DELAGRANGE, H; MITTIG, W; BERG, FD; KUHN, W; METAG, [No Value; NOVOTNY, R; PFEIFFER, M; BOONSTRA, AL; LOHNER, H; VENEMA, LB; WILSCHUT, HW; HENNING, W; HOLZMANN, R; MAYER, RS; SIMON, R; ARDOUIN, D; DABROWSKI, H; ERAZMUS, B; LEBRUN, C; SEZAC, L; LAUTRIDOU, P; QUEBERT, J; BALLESTER, F; CASAL, E; DIAZ, J; FERRERO, JL; MARQUES, M; MARTINEZ, G; NIFENECKER, H; FORNAL, B; FREINDL, L; SUJKOWSKI, Z; MATULEWICZ, T

    1992-01-01

    The present experimental knowledge on hard photon production in heavy ion collisions is summarized. An attempt to measure for the first time the intensity interference using photons in the MEV range is described. The effect is interpreted in terms of spatial and temporal extent of the photon's

  14. Heavy ion collisions at collider energies – Insights from PHENIX

    Indian Academy of Sciences (India)

    ken 305-0801, Japan. 15Korea University, Seoul ... early stages of high energy heavy-ion collisions where quark matter is expected to form. .... PHENIX has published spectra of charged pions, kaons, protons and their anti-particles over a broad ...

  15. Gamma-ray spectroscopy with relativistic exotic heavy-ions

    Indian Academy of Sciences (India)

    Vol. 57, No. 1. — journal of. July 2001 physics pp. 161–164. Gamma-ray spectroscopy with relativistic exotic heavy-ions. SAMIT MANDAL, J GERL, H GEISSEL, K HAUSCHILD. ¿. , M HELLSTR ¨OM, ... large [2,3] to perform a meaningful high spin decay spectroscopy of exotic nuclei. At the same time relativistic Coulomb ...

  16. Calculating Fragmentation Functions in Heavy Ion Physics Simulations

    Science.gov (United States)

    Hughes, Charles; Aukerman, Alex; Krobatsch, Thomas; Matyja, Adam; Nattrass, Christine; Neuhaus, James; Sorensen, Soren; Witt, William

    2017-09-01

    A hot dense liquid of quarks and gluons called a Quark Gluon Plasma (QGP) is formed in high energy nuclear collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider. The high energy partons which scatter during these collisions can serve as probes for measuring QGP bulk properties. The details of how partons lose energy to the QGP medium as they traverse it can be used to constrain models of their energy loss. Specifically, measurements of fragmentation functions in the QGP medium can provide experimental constraints on theoretical parton energy loss mechanisms. However, the high background in heavy ion collisions limits the precision of these measurements. We investigate methods for measuring fragmentation functions in a simple model in order to assess their feasibility. We generate a data-driven heavy ion background based on measurements of charged hadron transverse momentum spectra, charged hadron azimuthal flow, and charged hadron rapidity spectra. We then calculate fragmentation functions in this heavy ion background and compare to calculations in proton-proton simulations. We present the current status of these studies.

  17. Physics Opportunities in Ultraperipheral Heavy Ion Collisions at LHC

    OpenAIRE

    Baur, G.

    2001-01-01

    Due to coherence, there are strong electromagnetic fields of short duration in very peripheral heavy ion collisions. They give rise to photon-photon and photon-nucleus collisions with high flux. Photon-photon and photon-hadron physics at various invariant mass scales are discussed.

  18. Photoluminescence and Raman studies in swift heavy ion irradiated ...

    Indian Academy of Sciences (India)

    Administrator

    Swift heavy ions (SHI) cause intense electronic excita- tions along the ion trajectory when they pass through material that may result in defect production or amorphiza- tion or phase transformation on nanometer scale (Bolse et al 2004; Wang et al 2004). Thus, it is interesting to know the effect of strong electronic excitation ...

  19. Heavy ions: Results from the Large Hadron Collider

    Indian Academy of Sciences (India)

    2012-10-02

    Oct 2, 2012 ... accelerator, designed to address some of the most fundamental questions of recent times such as, whether Higgs ... Knowledge of the space-time evolution of the system produced in high-energy heavy-ion collisions .... The information about the freeze-out volume and lifetime of the created system in p–p.

  20. Subthreshold photons in heavy-ion reactions at intermediate energies

    NARCIS (Netherlands)

    Martinez, G

    1998-01-01

    In the present talk, I discuss about the properties of the energetic photons produced in heavy-ion reactions. I show that they are sensitive to the maximum density reached in the first stage of the nuclear reaction. Then, the existence of a thermal contribution to the photon differential

  1. Recent relativistic heavy ion collider results on photon, dilepton and ...

    Indian Academy of Sciences (India)

    large baryon density, the so-called quark gluon plasma. We focus on a specific category of observables: the electromagnetic probes which cover a large spectrum of experimental studies. Keywords. Quark gluon plasma; relativistic heavy ion collider; photon; vector meson; thermal dilepton; heavy quarks. PACS No. 25.75.Cj.

  2. Electromagnetic dissociation effects in galactic heavy-ion fragmentation

    Science.gov (United States)

    Norbury, J. W.; Townsend, L. W.

    1986-01-01

    Methods for calculating cross sections for the breakup of galactic heavy ions by the Coulomb fields of the interacting nuclei are presented. By using the Weizsacker-Williams method of virtual quanta, estimates of electromagnetic dissociation cross sections for a variety of reactions applicable to galactic cosmic ray shielding studies are presented and compared with other predictions and with available experimental data.

  3. Classical simulations of heavy-ion fusion reactions and weakly ...

    Indian Academy of Sciences (India)

    This model is extended to simulate heavy-ion reactions such as 6Li + 209Bi involving the weakly-bound projectile considered as a weakly-bound cluster of deuteron and 4He nuclei, thus, simulating a 3-body system in 3S-CMD model. All the essential features of breakup reactions, such as complete fusion, incomplete fusion ...

  4. Inferring Magnetospheric Heavy Ion Density using EMIC Waves

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun-Hwa; Johnson, Jay R.; Kim, Hyomin; Lee, Dong-Hun

    2014-05-01

    We present a method to infer heavy ion concentration ratios from EMIC wave observations that result from ionion hybrid (IIH) resonance. A key feature of the ion-ion hybrid resonance is the concentration of wave energy in a field-aligned resonant mode that exhibits linear polarization. This mode converted wave is localized at the location where the frequency of a compressional wave driver matches the IIH resonance condition, which depends sensitively on the heavy ion concentration. This dependence makes it possible to estimate the heavy ion concentration ratio. In this letter, we evaluate the absorption coefficients at the IIH resonance at Earth's geosynchronous orbit for variable concentrations of He+ and field-aligned wave numbers using a dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentrations, it only occurs for a limited range of field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Using the wave absorption and observed EMIC waves from GOES-12 satellite, we demonstrate how this technique can be used to estimate that the He+ concentration is around 4% near L = 6.6.

  5. Simple estimates of excitation energy sharing between heavy and light fragments in heavy-ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Dasso, C.H.; Lozano, M.; Pollarolo, G.

    1985-12-01

    Qualitative arguments are used to estiamte the ratio of excitation energies between heavy and light fragments for asymmetric heavy-ion collisions. The value of this quantity is linked to the relative role played by inelastic and transfer degrees of freedom and thereby to an approximate function of the total kinetic energy loss. A numerical analysis that confirms the trends anticipated by the simple arguments is performed for the reactions /sup 56/Fe+ /sup 238/U and /sup 86/Kr+ /sup 208/Pb at bombarding energies in the laboratory of 476 and 1565 MeV, respectively.

  6. The two-photon exchange contribution to elastic electron-nucleon scattering at large momentum transfer

    Energy Technology Data Exchange (ETDEWEB)

    Andrei V. Afanasev; Stanley J. Brodsky; Carl E. Carlson; Yu-Chun Chen; Marc Vanderhaeghen

    2005-01-01

    We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer by using a quark-parton representation of virtual Compton scattering. We thus can relate the two-photon exchange amplitude to the generalized parton distributions which also enter in other wide angle scattering processes. We find that the interference of one- and two-photon exchange contribution is able to substantially resolve the difference between electric form factor measurements from Rosenbluth and polarization transfer experiments.

  7. Deuteron-induced nucleon transfer reactions within an ab initio framework: First application to p -shell nuclei

    Science.gov (United States)

    Raimondi, Francesco; Hupin, Guillaume; Navrátil, Petr; Quaglioni, Sofia

    2016-05-01

    Background: Low-energy transfer reactions in which a proton is stripped from a deuteron projectile and dropped into a target play a crucial role in the formation of nuclei in both primordial and stellar nucleosynthesis, as well as in the study of exotic nuclei using radioactive beam facilities and inverse kinematics. Ab initio approaches have been successfully applied to describe the 3H (d ,n )4He and 3He(d ,p )4He fusion processes. Purpose: An ab initio treatment of transfer reactions would also be desirable for heavier targets. In this work, we extend the ab initio description of (d ,p ) reactions to processes with light p -shell nuclei. As a first application, we study the elastic scattering of deuterium on 7Li and the 7Li(d ,p )8Li transfer reaction based on a two-body Hamiltonian. Methods: We use the no-core shell model to compute the wave functions of the nuclei involved in the reaction, and describe the dynamics between targets and projectiles with the help of microscopic-cluster states in the spirit of the resonating group method. Results: The shapes of the excitation functions for deuterons impinging on 7Li are qualitatively reproduced up to the deuteron breakup energy. The interplay between d -7Li and p -8Li particle-decay channels determines some features of the 9Be spectrum above the d +7Li threshold. Our prediction for the parity of the 17.298 MeV resonance is at odds with the experimental assignment. Conclusions: Deuteron stripping reactions with p -shell targets can now be computed ab initio, but calculations are very demanding. A quantitative description of the 7Li(d ,p )8Li reaction will require further work to include the effect of three-nucleon forces and additional decay channels and to improve the convergence rate of our calculations.

  8. Heavy-ion radiation induced bystander effect in mice

    Science.gov (United States)

    Liang, Shujian; Sun, Yeqing; Zhang, Meng; Wang, Wei; Cui, Changna

    2012-07-01

    Radiation-induced bystander effect is defined as the induction of damage in neighboring non-hit cells by signals released from directly-irradiated cells. Recently, Low dose of high LET radiation induced bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. Genomic, epigenetic, metabolomics and proteomics play significant roles in regulating heavy-ion radiation stress responses in mice. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male mice head were exposed to 2000mGy dose of 12C heavy-ion radiation and the distant organ liver was detected on 1h, 6h, 12h and 24h after radiation, respectively. MSAP was used to monitor the level of polymorphic DNA methylation changes. The results show that heavy-ion irradiate mouse head can induce liver DNA methylation changes significantly. The percent of DNA methylation changes are time-dependent and highest at 6h after radiation. We also prove that the hypo-methylation changes on 1h and 6h after irradiation. But the expression level of DNA methyltransferase DNMT3a is not changed. UPLC/Synapt HDMS G2 was employed to detect the proteomics of bystander liver 1h after irradiation. 64 proteins are found significantly different between treatment and control group. GO process show that six of 64 which were unique in irradiation group are associated with apoptosis and DNA damage response. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo.

  9. Heavy-ion tumor therapy: Physical and radiobiological benefits

    Science.gov (United States)

    Schardt, Dieter; Elsässer, Thilo; Schulz-Ertner, Daniela

    2010-01-01

    High-energy beams of charged nuclear particles (protons and heavier ions) offer significant advantages for the treatment of deep-seated local tumors in comparison to conventional megavolt photon therapy. Their physical depth-dose distribution in tissue is characterized by a small entrance dose and a distinct maximum (Bragg peak) near the end of range with a sharp fall-off at the distal edge. Taking full advantage of the well-defined range and the small lateral beam spread, modern scanning beam systems allow delivery of the dose with millimeter precision. In addition, projectiles heavier than protons such as carbon ions exhibit an enhanced biological effectiveness in the Bragg peak region caused by the dense ionization of individual particle tracks resulting in reduced cellular repair. This makes them particularly attractive for the treatment of radio-resistant tumors localized near organs at risk. While tumor therapy with protons is a well-established treatment modality with more than 60 000 patients treated worldwide, the application of heavy ions is so far restricted to a few facilities only. Nevertheless, results of clinical phase I-II trials provide evidence that carbon-ion radiotherapy might be beneficial in several tumor entities. This article reviews the progress in heavy-ion therapy, including physical and technical developments, radiobiological studies and models, as well as radiooncological studies. As a result of the promising clinical results obtained with carbon-ion beams in the past ten years at the Heavy Ion Medical Accelerator facility (Japan) and in a pilot project at GSI Darmstadt (Germany), the plans for new clinical centers for heavy-ion or combined proton and heavy-ion therapy have recently received a substantial boost.

  10. An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: Bulk properties and dynamical evolution

    Directory of Open Access Journals (Sweden)

    Panagiota Foka

    2016-11-01

    Full Text Available The first collisions of lead nuclei, delivered by the CERN Large Hadron Collider (LHC at the end of 2010, at a centre-of-mass energy per nucleon pair sNN= 2.76 TeV, marked the beginning of a new era in ultra-relativistic heavy-ion physics. Following the Run 1 period, LHC also successfully delivered Pb–Pb collisions at the collision energy sNN= 5.02 TeV at the end of 2015. The study of the properties of the produced hot and dense strongly-interacting matter at these unprecedented energies is experimentally pursued by all four big LHC experiments, ALICE, ATLAS, CMS, and LHCb. This review presents selected experimental results from heavy-ion collisions delivered during the first three years of the LHC operation focusing on the bulk matter properties and the dynamical evolution of the created system. It also presents the first results from Run 2 heavy-ion data at the highest energy, as well as from the studies of the reference pp and p–Pb systems, which are an integral part of the heavy-ion programme.

  11. Status report on the Lawrence Berkeley Laboratory heavy ion fusion program

    Energy Technology Data Exchange (ETDEWEB)

    Keefe, D.; Faltens, A.; Hoyer, E.

    1978-11-01

    This status report is presented in three sections: (1) a design and cost procedure for heavy-ion induction LINACS, (2) theoretical activities, and (3) the experimental program on heavy ion fusion at LBL. (MOW)

  12. EDITORIAL: Focus on Heavy Ions in Biophysics and Medical Physics FOCUS ON HEAVY IONS IN BIOPHYSICS AND MEDICAL PHYSICS

    Science.gov (United States)

    Durante, Marco

    2008-07-01

    Interest in energetic heavy ions is rapidly increasing in the field of biomedicine. Heavy ions are normally excluded from radiation protection, because they are not normally experienced by humans on Earth. However, knowledge of heavy ion biophysics is necessary in two fields: charged particle cancer therapy (hadrontherapy), and radiation protection in space missions. The possibility to cure tumours using accelerated heavy charged particles was first tested in Berkeley in the sixties, but results were not satisfactory. However, about 15 years ago therapy with carbon ions was resumed first in Japan and then in Europe. Heavy ions are preferable to photons for both physical and biological characteristics: the Bragg peak and limited lateral diffusion ensure a conformal dose distribution, while the high relative biological effectiveness and low oxygen enhancement ration in the Bragg peak region make the beam very effective in treating radioresistant and hypoxic tumours. Recent results coming from the National Institute of Radiological Sciences in Chiba (see the paper by Dr Tsujii and co-workers in this issue) and GSI (Germany) provide strong clinical evidence that heavy ions are indeed an extremely effective weapon in the fight against cancer. However, more research is needed in the field, especially on optimization of the treatment planning and risk of late effects in normal tissue, including secondary cancers. On the other hand, high-energy heavy ions are present in galactic cosmic radiation and, although they are rare as compared to protons, they give a major contribution in terms of equivalent dose to the crews of manned space exploratory-class missions. Exploration of the Solar System is now the main goal of the space program, and the risk caused by exposure to galactic cosmic radiation is considered a serious hindrance toward this goal, because of the high uncertainty on late effects of energetic heavy nuclei, and the lack of effective countermeasures. Risks

  13. Accelerator-Based Studies of Heavy Ion Interactions Relevant to Space Biomedicine

    Science.gov (United States)

    Miller, J.; Heilbronn, L.; Zeitlin, C.

    1999-01-01

    Alternating Gradient Synchrotron at Brookhaven National Laboratory (BNL AGS) and the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan. Until fairly recently most of these experiments were done to investigate fundamental problems in nuclear physics, but with the increasing interest in heavy charged particles on the part of the space flight, radiobiology and radiotherapy communities, an increasing number of experiments are being directed at these areas. Some of these measurements are discussed in references therein. Over the past several years, our group has taken cross section and fluence data at the AGS and HIMAC for several incident beams with nuclear charge, Z, between 6 and 26 at energies between 290 and 1050 MeV/nucleon. Iron (Z = 26) has been studied most extensively, since it is the heaviest ion present in significant numbers in the GCR. Targets have included tissue-equivalent and proposed shielding materials, as well as a variety of elemental targets for cross section measurements. Most of the data were taken along the beam axis, but measurements have been made off-axis, as well. Here we present selected data and briefly discuss some implications for spacecraft and planetary habitat design.

  14. Chiral symmetry restoration versus deconfinement in heavy-ion collisions at high baryon density

    Science.gov (United States)

    Bratkovskaya, E. L.; Palmese, A.; Cassing, W.; Seifert, E.; Steinert, T.; Moreau, P.

    2017-07-01

    The effect of the chiral symmetry restoration (CSR) on observables from heavy-ion collisions is studied in the energy range \\sqrt{{s}NN}=3-20 {GeV} within the Parton-Hadron-String Dynamics (PHSD) transport approach. The PHSD includes the deconfinement phase transition as well as essential aspects of CSR in the dense and hot hadronic medium, which are incorporated in the Schwinger mechanism for the hadronic particle production. We adopt different parametrizations of the nuclear equation of state from the non-linear σ - ω model, which enter in the computation of the quark scalar density for the CSR mechanism, in order to estimate the uncertainty in our calculations. For the pion-nucleon Σ-term we adopt Σ π ≈ 45 MeV which corresponds to some ‘world average’. Our systematic studies show that chiral symmetry restoration plays a crucial role in the description of heavy-ion collisions at \\sqrt{{s}NN}=3-20 {GeV}, realizing an increase of the hadronic particle production in the strangeness sector with respect to the non-strange one. We identify particle abundances and rapidity spectra to be suitable probes in order to extract information about CSR, while transverse mass spectra are less sensitive. Our results provide a microscopic explanation for the “horn” structure in the excitation function of the K +/π + ratio: the CSR in the hadronic phase produces the steep increase of this particle ratio up to \\sqrt{{s}NN}≈ 7 {GeV}, while the drop at higher energies is associated to the appearance of a deconfined partonic medium.

  15. Heavy Ion Collisions at the LHC - Last Call for Predictions

    Energy Technology Data Exchange (ETDEWEB)

    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

    2008-02-25

    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

  16. Mean angular momenta in heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, D. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Scarlassara, F. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Bednarczyk, P. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Beghini, S. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Corradi, L. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Montagnoli, G. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Mueller, L. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Napoli, D.R. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Petrache, C.M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Varier, K.M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Soramel, F. [Dipartimento di Fisica, Universita di Udine, Udine (Italy); Spolaore, P. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Stefanini, A.M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy); Segato, G.F. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Signorini, C. [Dipartimento di Fisica, Universita di Padova and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Zhang, H. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, 35020 Legnaro (Padova) (Italy)

    1995-02-06

    The results of the measurement of fusion cross sections {sigma}{sub fus} and mean angular momenta left angle l right angle for the five systems {sup 16}O+{sup 112}Cd, {sup 28}Si+{sup 94,100}Mo and {sup 58,64}Ni+{sup 64}Ni are reported. The direct comparison between the fusion excitation function and left angle l right angle (E) confirms consistency of the two independent observables. By analyzing the data in the framework of the coupled channels (CC) approach a good overall agreement between experiment and model predictions has been found. In particular the influence of 2n-transfer channels with positive Q-values is put in evidence. ((orig.)).

  17. An Experimental Review on Elliptic Flow of Strange and Multistrange Hadrons in Relativistic Heavy Ion Collisions

    Directory of Open Access Journals (Sweden)

    Shusu Shi

    2016-01-01

    Full Text Available Strange hadrons, especially multistrange hadrons, are good probes for the early partonic stage of heavy ion collisions due to their small hadronic cross sections. In this paper, I give a brief review on the elliptic flow measurements of strange and multistrange hadrons in relativistic heavy ion collisions at Relativistic Heavy Ion Collider (RHIC and Large Hadron Collider (LHC.

  18. The effects of heavy ion particles on the developing murine cerebellum, with special reference to cell death

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Chikako; Yaoi, Takeshi; Fushiki, Shinji [Kyoto Prefectural Univ. of Medicine (Japan). Research Inst. for Neurological Diseases and Geriatrics; Nojima, Kumie [National Inst. of Radiological Sciences, Chiba (Japan). Internatinal Space Radiation Lab.

    2003-07-01

    We report here the effects of heavy ion beams on postnatal mouse cerebellar development, with reference to cell death. Eight-day-old B6C3F1 mice were irradiated with single doses of 0.1, 0.25, 0.5, 1.0, and 2.0 Gy, using a carbon beam of 290 MeV delivered from a heavy ion medical accelerator in Chiba (HIMAC). To compare the effects of X-rays with those of accelerated carbon ions, 8-day-old mice were exposed to X-rays single doses of 0.1, 0.25, 0.5, 1.0, and 2.0 Gy, respectively. Pups were fixed at 1, 6, 12 and 24 hr after exposure to HIMAC beams or X-rays. Four-{mu}m-thick parasagittal sections of the cerebella were processed for hematoxylin-eosin staining as well as for staining with the TUNEL (terminal dUTP nick-end labeling) technique. The density of fragmented nuclei in the external granular layer increased with time, peaking at 6 hr after exposure, in both the HIMAC and X-irradiated groups. In the HIMAC groups, the density was significantly higher in those animals exposed to 0.25 Gy or more compared to 0 Gy, whereas in the X-irradiated groups it was significantly higher in those mice exposed to 0.5 Gy or more. Electron microscopic examinations revealed chromatin condensation in the cell nuclei in the HIMAC groups. This is the first in vivo evidence that apoptotic cell death is induced in developing mouse cerebellum after exposure to heavy ion particles. The difference in the frequency of dying cells between exposure to heavy ion particles and to X-rays may reflect the high linear energy transfer (LET) associated with a heavy ion beam. (author)

  19. Actinide Production in the Reaction of Heavy Ions withCurium-248

    Energy Technology Data Exchange (ETDEWEB)

    Moody, Kenton James [Univ. of California, Berkeley, CA (United States)

    1983-07-01

    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 248Cm with 18O, 86Kr and 136Xe projectiles at several energies near and below the Coulomb barrier were determined. The results are compared with yields from 48Ca and 238U bombardments of 248Cm. 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 136Xe and 238U the new species 248Am, 249Am and 247Pu should be produced with large cross sections from a 248Cm target. A preliminary, unsuccessful attempt to isolate 247Pu 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 251Bk decay, necessary for calculating the 251Bk cross section, are also determined.

  20. Single ion induced surface nanostructures: a comparison between slow highly charged and swift heavy ions.

    Science.gov (United States)

    Aumayr, Friedrich; Facsko, Stefan; El-Said, Ayman S; Trautmann, Christina; Schleberger, Marika

    2011-10-05

    This topical review focuses on recent advances in the understanding of the formation of surface nanostructures, an intriguing phenomenon in ion-surface interaction due to the impact of individual ions. In many solid targets, swift heavy ions produce narrow cylindrical tracks accompanied by the formation of a surface nanostructure. More recently, a similar nanometric surface effect has been revealed for the impact of individual, very slow but highly charged ions. While swift ions transfer their large kinetic energy to the target via ionization and electronic excitation processes (electronic stopping), slow highly charged ions produce surface structures due to potential energy deposited at the top surface layers. Despite the differences in primary excitation, the similarity between the nanostructures is striking and strongly points to a common mechanism related to the energy transfer from the electronic to the lattice system of the target. A comparison of surface structures induced by swift heavy ions and slow highly charged ions provides a valuable insight to better understand the formation mechanisms. © 2011 IOP Publishing Ltd

  1. Probing the nuclear symmetry energy with heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    De Filippo E.

    2015-01-01

    Full Text Available Heavy ion collisions (HIC have been widely used to extract the parametrization of symmetry energy term of nuclear equation of state as a function of barionic density. HIC in fact are a unique tool in terrestrial laboratories to explore the symmetry energy around the saturation density (ρ0 = 0.16fm−3 from sub-saturation densities (Fermi energies towards compressed nuclear matter (ρ > 2 − 3ρ0 that can be reached at relativistic energies, as a function of different conditions of temperature, mass asymmetry and isospin. One of the main study at present is to reach a coherent description of EOS of asymmetric nuclear matter from heavy ion collisions of stable and exotic nuclei, nuclear structure studies and astrophysical observations. In this work an overview of the current status of the research is shortly reviewed together with new perspectives aimed to reduce the present experimental and theoretical uncertainties.

  2. Particle Correlations with Heavy Ions at LHC Energies

    CERN Document Server

    Erazmus, B; Roy, C; Werner, K; Lednicky, R; Lyuboshitz, V L; Mikhailov, K; Stavinsky, A V; Pluta, J; Sinyukov, Yu M

    1998-01-01

    The ALICE detector will offer very good conditions to study the space-time characteristics of particle production in heavy-ion collisions at LHC from measurements of the correlation function of identical and non-identical particles at small relative velocities. The correlations - induced by Coulomb and nuclear final-state interactions - of non-identical particles appear to be directly sensitive to the space-time asymmetries of particle production allowing, in particular, a measurement of the mean relative delays in particle emission at time scales as small as few fm/c. The problem of Coulomb interaction of the correlated particles is particularly important in the case of the large effective volumes formed in ultra-relativistic heavy-ion reactions.

  3. Spiraling Beam Illumination Uniformity on Heavy Ion Fusion Target

    CERN Document Server

    Kurosaki, T; Noguchi, K; Koseki, S; Barada, D; Ma, Y Y; Ogoyski, A I; Barnard, J J; Logan, B G

    2012-01-01

    A few percent wobbling-beam illumination nonuniformity is realized in heavy ion inertial confinement fusion (HIF) by a spiraling beam axis motion in the paper. So far the wobbling heavy ion beam (HIB) illumination was proposed to realize a uniform implosion in HIF. However, the initial imprint of the wobbling HIBs was a serious problem and introduces a large unacceptable energy deposition nonuniformity. In the wobbling HIBs illumination, the illumination nonuniformity oscillates in time and space. The oscillating-HIB energy deposition may contribute to the reduction of the HIBs illumination nonuniformity. The wobbling HIBs can be generated in HIB accelerators and the oscillating frequency may be several 100MHz-1GHz. Three-dimensional HIBs illumination computations presented here show that the few percent wobbling HIBs illumination nonuniformity oscillates successfully with the same wobbling HIBs frequency.

  4. Activation of accelerator construction materials by heavy ions

    Science.gov (United States)

    Katrík, P.; Mustafin, E.; Hoffmann, D. H. H.; Pavlovič, M.; Strašík, I.

    2015-12-01

    Activation data for an aluminum target irradiated by 200 MeV/u 238U ion beam are presented in the paper. The target was irradiated in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. The purpose of the experiment was to study the role of primary particles, projectile fragments, and target fragments in the activation process using the depth profiling of residual activity. The study brought information on which particles contribute dominantly to the target activation. The experimental data were compared with the Monte Carlo simulations by the FLUKA 2011.2c.0 code. This study is a part of a research program devoted to activation of accelerator construction materials by high-energy (⩾200 MeV/u) heavy ions at GSI Darmstadt. The experimental data are needed to validate the computer codes used for simulation of interaction of swift heavy ions with matter.

  5. What have we learned from jets in heavy ion collisions

    Science.gov (United States)

    Nattrass, Christine

    2017-09-01

    The Quark-Gluon Plasma (QGP) is created in high energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). The properties of this medium is transparent to electromagnetic probes but nearly opaque to colored probes. Hard partons fragment and hadronize into a collimated spray of particles called a jet. The partons lose energy as they traverse the medium, a process called jet quenching. Most of the lost energy is still correlated with the parent parton, contributing to particle production at larger angles and lower momenta relative to the parent parton than in proton-proton collisions. This partonic energy loss can be measured through several observables, each of which give different insights into the degree and mechanism of energy loss. The measurements to date are summarized and the path forward is discussed.

  6. Probing subnucleon scale fluctuations in ultraperipheral heavy ion collisions

    Science.gov (United States)

    Mäntysaari, Heikki; Schenke, Björn

    2017-09-01

    We show that introducing subnucleon scale fluctuations constrained by HERA diffractive J / Ψ production data significantly affects the incoherent diffractive J / Ψ production cross section in ultraperipheral heavy ion collisions. We find that the inclusion of the additional fluctuations increases the ratio of the incoherent to the coherent cross section approximately by a factor of 2, and modifies the transverse momentum spectra of the produced J / Ψ at momenta larger than the scale that corresponds to the distance scale of the subnucleonic fluctuations. We present predictions for J / Ψ production in ultraperipheral heavy ion collisions at √{sNN} = 5.02 TeV at the LHC and 200 GeV at RHIC.

  7. Probing subnucleon scale fluctuations in ultraperipheral heavy ion collisions

    Directory of Open Access Journals (Sweden)

    Heikki Mäntysaari

    2017-09-01

    Full Text Available We show that introducing subnucleon scale fluctuations constrained by HERA diffractive J/Ψ production data significantly affects the incoherent diffractive J/Ψ production cross section in ultraperipheral heavy ion collisions. We find that the inclusion of the additional fluctuations increases the ratio of the incoherent to the coherent cross section approximately by a factor of 2, and modifies the transverse momentum spectra of the produced J/Ψ at momenta larger than the scale that corresponds to the distance scale of the subnucleonic fluctuations. We present predictions for J/Ψ production in ultraperipheral heavy ion collisions at sNN=5.02 TeV at the LHC and 200 GeV at RHIC.

  8. Probing transverse momentum broadening in heavy ion collisions

    Directory of Open Access Journals (Sweden)

    A.H. Mueller

    2016-12-01

    Full Text Available We study the dijet azimuthal de-correlation in relativistic heavy ion collisions as an important probe of the transverse momentum broadening effects of a high energy jet traversing the quark–gluon plasma. We take into account both the soft gluon radiation in vacuum associated with the Sudakov logarithms and the jet PT-broadening effects in the QCD medium. We find that the Sudakov effects are dominant at the LHC, while the medium effects can play an important role at RHIC energies. This explains why the LHC experiments have not yet observed sizable PT-broadening effects in the measurement of dijet azimuthal correlations in heavy ion collisions. Future investigations at RHIC will provide a unique opportunity to study the PT-broadening effects and help to pin down the underlying mechanism for jet energy loss in a hot and dense medium.

  9. Heavy ion physics : Exhibition Lepton-Photon 2001

    CERN Multimedia

    2001-01-01

    High-energy Heavy Ion Physics studies strongly interacting matter at extreme energy densities.QCD predicts that at such densities hadronic matter turns into a plasma of deconfined quarks and gluons,the Quark Gluon Plasma (QGP).Matter in the Universe must have existed in this state up to about 10 ms after the Big Bang.Today QGP might exist in the c re of neutron stars.The study of the phase diagram of matter is a new approach to investigate QCD at its natural scale,L QCD ,and to address the fundamental questions of confinement and chiral-symmetry breaking.The combined results obtained by the SPS heavy ion experiments,in particular those obtained with the Pb beam,pr vide compelling evidence for the existence of a new state of matter featuring many of the characteristics predicted for the QGP.The ALICE experiment will carry this research into the LHC era.

  10. Jet studies in heavy ion collisions with the ATLAS detector

    CERN Document Server

    Slovak, Radim; The ATLAS collaboration

    2016-01-01

    In relativistic heavy ion collisions, a hot medium with a high density of unscreened color charges is produced. Jets are produced at the early stages of this collision and are known to become attenuated as they propagate through the hot matter. One manifestation of this energy loss is a lower yield of jets emerging from the medium than expected in the absence of medium effects. ATLAS has provided a quantification of this jet suppression by the jet Raa measurement in run 1 of LHC. A factor of two suppression was seen in central heavy ion collisions with respect to pp collisions. The Raa exhibited only a week, if any, rapidity dependence, and a slow rise with increasing jet momentum. This talk summarizes the run 1 results on the inclusive jet production and the new results on dijet measurements.

  11. The threshold anomaly for heavy-ion scattering

    Energy Technology Data Exchange (ETDEWEB)

    Satchler, G.R.

    1987-01-01

    The real parts of optical potentials deduced from heavy-ion scattering measurements become rapidly more attractive as the bombarding energy is reduced close to the top of the Coulomb barrier. This behavior is explained as a coupled-channels effect, and is related to the corresponding reduction in the absorptive potential through a dispersion relation which expresses the consequences of causality. Another manifestation of this ''anomaly'' is the striking enhancement observed for the near- and sub-barrier fusion of two heavy ions. The barrier penetration model of fusion is examined critically in this context. It is also stressed that similar anomalies could appear in the energy dependence of nonelastic scattering. 21 refs., 4 figs.

  12. <span class="hlt">Heavy-Ion</span> Imaging Applied To Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J. I.; Tobias, C. A.; Capp, M. P.; Benton, E. V.; Holley, W. R.; Gray, Joel E.; Hendee, William R.; Haus, Andrew G.; Properzio, William S.

    1980-08-18

    Heavy particle radiography is a newly developed noninvasive low dose imaging procedure with increased resolution of minute density differences in soft tissues of the body. The method utilizes accelerated high energy ions, primarily carbon and neon, at the BEVALAC accelerator at the Lawrence Berkeley Laboratory. The research program applied to medicine utilizes heavy-ion radiography for low dose mammography, for treatment planning for cancer patients, and for imaging and accurate densitometry of skeletal structures and brain and spinal neoplasms. The presentation will be illustrated with clinical cases under study. Discussion will include the potential of heavy-ion imaging, and particularly reconstruction tomography, as an adjunct to existing diagnostic imaging procedures in medicine, both for the applications to the diagnosis, management and treatment of clinical cancer in man, but also for the early detection of small soft tissue tumors at low radiation dose.

  13. Multiple beam induction accelerators for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Seidl, Peter A., E-mail: paseidl@lbl.gov [Lawrence Berkeley National Laboratory, US (United States); Barnard, John J. [Lawrence Livermore National Laboratory, US (United States); Faltens, Andris [Lawrence Berkeley National Laboratory, US (United States); Friedman, Alex [Lawrence Livermore National Laboratory, US (United States); Waldron, William L. [Lawrence Berkeley National Laboratory, US (United States)

    2014-01-01

    Induction accelerators are appealing for heavy-ion driven inertial fusion energy (HIF) because of their high efficiency and their demonstrated capability to accelerate high beam current (≥10 kA in some applications). For the HIF application, accomplishments and challenges are summarized. HIF research and development has demonstrated the production of single ion beams with the required emittance, current, and energy suitable for injection into an induction linear accelerator. Driver scale beams have been transported in quadrupole channels of the order of 10% of the number of quadrupoles of a driver. We review the design and operation of induction accelerators and the relevant aspects of their use as drivers for HIF. We describe intermediate research steps that would provide the basis for a heavy-ion research facility capable of heating matter to fusion relevant temperatures and densities, and also to test and demonstrate an accelerator architecture that scales well to a fusion power plant.

  14. Activation of accelerator construction materials by heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Katrík, P., E-mail: p.katrik@gsi.de [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany); Mustafin, E. [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany); Hoffmann, D.H.H. [TU Darmstadt, Schlossgartenstraße 9, D-64289 (Germany); Pavlovič, M. [FEI STU Bratislava, Ilkovičova 3, SK-81219 (Slovakia); Strašík, I. [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany)

    2015-12-15

    Activation data for an aluminum target irradiated by 200 MeV/u {sup 238}U ion beam are presented in the paper. The target was irradiated in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. The purpose of the experiment was to study the role of primary particles, projectile fragments, and target fragments in the activation process using the depth profiling of residual activity. The study brought information on which particles contribute dominantly to the target activation. The experimental data were compared with the Monte Carlo simulations by the FLUKA 2011.2c.0 code. This study is a part of a research program devoted to activation of accelerator construction materials by high-energy (⩾200 MeV/u) heavy ions at GSI Darmstadt. The experimental data are needed to validate the computer codes used for simulation of interaction of swift heavy ions with matter.

  15. Scaled beam merging experiment for heavy ion inertial fusion

    Directory of Open Access Journals (Sweden)

    P. A. Seidl

    2003-09-01

    Full Text Available Transverse beam combining is a cost-saving option employed in many designs for heavy ion fusion drivers. However, the resultant transverse phase space dilution must be minimized so as not to sacrifice focusability at the target. A prototype combining experiment has been completed employing four 3-mA Cs^{+} beams injected at 160 keV. The focusing elements upstream of the merge consist of four quadrupoles and a final combined-function element (quadrupole and dipole. Following the merge, the resultant single beam is transported in a single alternating gradient channel where the subsequent evolution of the distribution function is diagnosed. The results are in fair agreement with particle-in-cell simulations. They indicate that for some heavy ion fusion driver designs, the phase space dilution from merging is acceptable.

  16. Highlights from STAR heavy ion program arXiv

    CERN Document Server

    Okorokov, V.A.

    Recent experimental results obtained in STAR experiment at the Relativistic heavy-ion collider (RHIC) with ion beams will be discussed. Investigations of different nuclear collisions in some recent years focus on two main tasks, namely, detail study of quark-gluon matter properties and exploration of the quantum chromodynamics (QCD) phase diagram. Results at top RHIC energy show clearly the collective behavior of heavy quarks in nucleus-nucleus interactions. Jet and heavy hadron measurements lead to new constraints for energy loss models for various flavors. Heavy-ion collisions are unique tool for the study of topological properties of theory as well as the magneto-hydrodynamics of strongly interacting matter. Experimental results obtained for discrete QCD symmetries at finite temperatures confirm indirectly the topologically non-trivial structure of QCD vacuum. Finite global vorticity observed in non-central Au+Au collisions can be considered as important signature for presence of various chiral effects in ...

  17. Charged Hadron Multiplicity Distribution at Relativistic Heavy-Ion Colliders

    Directory of Open Access Journals (Sweden)

    Ashwini Kumar

    2013-01-01

    Full Text Available The present paper reviews facts and problems concerning charge hadron production in high energy collisions. Main emphasis is laid on the qualitative and quantitative description of general characteristics and properties observed for charged hadrons produced in such high energy collisions. Various features of available experimental data, for example, the variations of charged hadron multiplicity and pseudorapidity density with the mass number of colliding nuclei, center-of-mass energies, and the collision centrality obtained from heavy-ion collider experiments, are interpreted in the context of various theoretical concepts and their implications. Finally, several important scaling features observed in the measurements mainly at RHIC and LHC experiments are highlighted in the view of these models to draw some insight regarding the particle production mechanism in heavy-ion collisions.

  18. Centrality dependence of midrapidity density from GeV to TeV heavy-ion collisions in the effective-energy universality picture of hadroproduction

    CERN Document Server

    Sarkisyan, Edward K.G.; Sahoo, Raghunath; Sakharov, Alexander S.

    2016-07-05

    The dependence on centrality, or on the number of nucleon participants, of the midrapidity density of charged particles measured in heavy-ion collisions at the collision energy of about 20 GeV at RHIC to the highest LHC energy of 5 TeV is investigated within the recently proposed effective-energy approach. This approach relates multihadron production in different types of collisions by combining, under the proper scaling of the collision energy, the constituent quark picture with Landau relativistic hydrodynamics. The measurements are shown to be well described based on the similarity of multihadron production process in (anti)proton-proton interactions and heavy-ion collisions driven by the centrality-dependent effective energy of participants.

  19. Study of multi-nucleon transfer reactions in {sup 58,} {sup 64}Ni + {sup 207}Pb collisions at the velocity filter SHIP

    Energy Technology Data Exchange (ETDEWEB)

    Comas, V.F.; Heinz, S.; Ackermann, D.; Heredia, J.A.; Hessberger, F.P.; Khuyagbaatar, J.; Kindler, B.; Lommel, B.; Mann, R. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet Frankfurt, Institut fuer Physik, Frankfurt (Germany)

    2013-09-15

    We investigated multi-nucleon transfer reactions in collisions of {sup 58}Ni + {sup 207}Pb and {sup 64}Ni + {sup 207}Pb at Coulomb barrier energies. The new aspect is that we used a velocity filter (SHIP at GSI) for the separation of the heavy target-like transfer products from background events. The isotopic identification was performed via the {alpha} decay properties of the reaction products. The goal of the experiment was to study the characteristics of multi-nucleon transfer reactions in the region of heavy nuclei and the applicability of existing separation and detection techniques, which are usually used for identification of heavy fusion-evaporation residues, to heavy transfer products. This was motivated by recent theoretical results from macroscopic-microscopic models which suggest deep inelastic transfer reactions in heavy systems as a means to produce new neutron-rich isotopes in the region of N = 126 and in the region of superheavy nuclei. In this paper we present the isotopic yields, the excitation functions and the excitation energies of the heavy transfer products with Z > 82 as well as the influence of shell effects on the reaction products. The influence of the different neutron numbers of the projectiles is also discussed. (orig.)

  20. Studying heavy-ion collisions with FAUST-QTS

    Directory of Open Access Journals (Sweden)

    Cammarata P.

    2015-01-01

    Full Text Available Heavy-ion collisions at lower energies provide a rich environment for investigating reaction dynamics. Recent theory has suggested a sensitivity to the symmetry energy and the equation of state via deformations of the reaction system and ternary breaking of the deformed reaction partners into three heavy fragments. A new detection system has been commissioned at Texas A&M University in an attempt to investigate some of the observables sensitive to the nuclear equation of state.

  1. New operational beam for the CERN heavy ion program

    CERN Document Server

    Chamings, J A; Hill, C E; Küchler, D; Lombardi, A M; O'Neill, M; Scrivens, R

    2004-01-01

    The use of indium beams in place of lead beams for the CERN heavy ion program was studied. It was found that the Indium beam emittance was measured downstream of the spectrometer by a quadrupole sean. The frequency of source adjustments to keep the beam current at a certain level was also studied. Results shows that the oven-resistance fluctuations were partially solved by using the oven power controller. (Edited abstract) 4 Refs.

  2. Six tesla analyzing magnet for heavy-ion beam transport

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.P.; Bollinger, L.; Erskine, J.; Genens, L.; Hoffman, J.

    1980-01-01

    A superconducting analyzer magnet for particle beam deflection has been designed and is being fabricated for use at the Argonne Tandem-Linac Accelerator System (ATLAS). This six tesla magnet will provide 45/sup 0/ of deflection for the heavy-ion beams from the ATLAS tandem electrostatic accelerator and together with its twin will replace the existing conventional 90/sup 0/ analyzer magnet which will become inadequate when ATLAS is completed.

  3. Heavy ion linear accelerator for radiation damage studies of materials

    Energy Technology Data Exchange (ETDEWEB)

    Kutsaev, Sergey V.; Mustapha, Brahim; Ostroumov, Peter N.; Nolen, Jerry; Barcikowski, Albert; Pellin, Michael; Yacout, Abdellatif

    2017-03-01

    A new eXtreme MATerial (XMAT) research facility is being proposed at Argonne National Laboratory to enable rapid in situ mesoscale bulk analysis of ion radiation damage in advanced materials and nuclear fuels. This facility combines a new heavy-ion accelerator with the existing high-energy X-ray analysis capability of the Argonne Advanced Photon Source. The heavy-ion accelerator and target complex will enable experimenters to emulate the environment of a nuclear reactor making possible the study of fission fragment damage in materials. Material scientists will be able to use the measured material parameters to validate computer simulation codes and extrapolate the response of the material in a nuclear reactor environment. Utilizing a new heavy-ion accelerator will provide the appropriate energies and intensities to study these effects with beam intensities which allow experiments to run over hours or days instead of years. The XMAT facility will use a CW heavy-ion accelerator capable of providing beams of any stable isotope with adjustable energy up to 1.2 MeV/u for U-238(50+) and 1.7 MeV for protons. This energy is crucial to the design since it well mimics fission fragments that provide the major portion of the damage in nuclear fuels. The energy also allows damage to be created far from the surface of the material allowing bulk radiation damage effects to be investigated. The XMAT ion linac includes an electron cyclotron resonance ion source, a normal-conducting radio-frequency quadrupole and four normal-conducting multi-gap quarter-wave resonators operating at 60.625 MHz. This paper presents the 3D multi-physics design and analysis of the accelerating structures and beam dynamics studies of the linac.

  4. Performance of the CERN Heavy Ion production complex

    CERN Document Server

    Manglunki, D; Bartosik, H; Bellodi, G; Blas, A; Bohl, T; Carli, C; Carlier, E; Cettour Cave, S; Cornelis, K; Damerau, H; Efthymiopoulos, I; Findlay, A; Gilardoni, S; Hancock, S; Jowett, JM; Kuchler, D; Maury, S; O'Neil, M; Papaphilippou, Y; Pasinelli, S; Scrivens, R; Tranquille, G; Vandorpe, B; Wehrle, U; Wenninger, J

    2012-01-01

    The second LHC ion run took place at 1.38 A TeV/c per beam in autumn 2011; more than 100 inverse microbarns were accumulated by each of the experiments. In addition, the LHC injector chain delivered primary Pb and secondary Be ion beams to fixed target experiments in the SPS North Area. This paper presents the current performance of the heavy ion production complex, and prospects to further improve it in the near future.

  5. Heavy ion linear accelerator for radiation damage studies of materials

    Science.gov (United States)

    Kutsaev, Sergey V.; Mustapha, Brahim; Ostroumov, Peter N.; Nolen, Jerry; Barcikowski, Albert; Pellin, Michael; Yacout, Abdellatif

    2017-03-01

    A new eXtreme MATerial (XMAT) research facility is being proposed at Argonne National Laboratory to enable rapid in situ mesoscale bulk analysis of ion radiation damage in advanced materials and nuclear fuels. This facility combines a new heavy-ion accelerator with the existing high-energy X-ray analysis capability of the Argonne Advanced Photon Source. The heavy-ion accelerator and target complex will enable experimenters to emulate the environment of a nuclear reactor making possible the study of fission fragment damage in materials. Material scientists will be able to use the measured material parameters to validate computer simulation codes and extrapolate the response of the material in a nuclear reactor environment. Utilizing a new heavy-ion accelerator will provide the appropriate energies and intensities to study these effects with beam intensities which allow experiments to run over hours or days instead of years. The XMAT facility will use a CW heavy-ion accelerator capable of providing beams of any stable isotope with adjustable energy up to 1.2 MeV/u for 238U50+ and 1.7 MeV for protons. This energy is crucial to the design since it well mimics fission fragments that provide the major portion of the damage in nuclear fuels. The energy also allows damage to be created far from the surface of the material allowing bulk radiation damage effects to be investigated. The XMAT ion linac includes an electron cyclotron resonance ion source, a normal-conducting radio-frequency quadrupole and four normal-conducting multi-gap quarter-wave resonators operating at 60.625 MHz. This paper presents the 3D multi-physics design and analysis of the accelerating structures and beam dynamics studies of the linac.

  6. Structural and electrical properties of swift heavy ion beam irradiated ...

    Indian Academy of Sciences (India)

    TECS

    Abstract. The present work deals with the mixing of iron and silicon by swift heavy ions in high-energy range. The thin film was deposited on a n-Si (111) substrate at 10. –6 torr and at room temperature. Irradia- tions were undertaken at room temperature using 120 MeV Au. +9 ions at the Fe/Si interface to investigate ion.

  7. Heavy-ion Results of the CMS Experiment

    CERN Document Server

    Boimska, B

    2016-01-01

    An overview of selected heavy-ion results of the CMS experiment is presented. Jet quenching, quarkonia suppression and two-particle angular correlation results are discussed. The measurements have been performed for lead–lead, proton–lead and proton–proton data samples recorded for Run 1 of the LHC accelerator. In the correlation analysis, low pile-up proton–proton collisions at an energy of 13 TeV (from Run 2) have been used as well

  8. Thermalization in the initial stage of heavy ion collisions

    Directory of Open Access Journals (Sweden)

    Zhu Yan

    2017-01-01

    Full Text Available The high density non-abelian matter produced in heavy ion collisions is extremely anisotropic. Prethermal dynamics for the anisotropic and weakly coupled matter is discussed. Thermalization is realized with the effective kinetic theory in the leading order accuracy of the weakly coupled expansion. With the initial condition from color glass condensate, hydrodynamization time for the LHC energies is realized to be about 1 fm/c, while the thermalization happens much later than the hydrodynamization.

  9. One nucleon transfer reactions around $^{68}$Ni at REX-ISOLDE

    CERN Multimedia

    Blazhev, A A; Kruecken, R; Mertzimekis, T; Darby, I G; Lagogiannis, A; Habs, D; Diriken, J V J; Patronis, N

    2008-01-01

    We intend to investigate the single particle properties of the neutron-rich Ni isotopes in the mass region around $^{68}$Ni and at a later stage towards the doubly-magic $^{78}$Ni. As a first experiment we propose to study the single particle character of the ground and first excited states of $^{67}$Ni. This nucleus will be the projectile-like reaction product for the one-neutron transfer reaction. A $^{66}$Ni beam at 3A MeV delivered from REX-ISOLDE will be directed on a CD$_{2}$ target. Protons produced from the (d,p) reaction will be detected either in singles or in coincidence with ${\\gamma}$-rays recorded by the MINIBALL array. The particles will be detected by the newly-built Si position-sensitive barrel configuration. The objectives of this work are the unambiguous determination of the spins and parities of the first excited states of $^{67}$Ni and measurement of the relative spectroscopic factors of those states as well as of the ground state. The experimental results will be compared with those from...

  10. Comparison of Model Calculations of Biological Damage from Exposure to Heavy Ions with Measurements

    Science.gov (United States)

    Kim, Myung-Hee Y.; Wu, Honglu; Hada, Megumi; Cucinotta, Francis

    The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LET g or X rays, the presence of shielding does not always reduce the radiation risks for energetic charged-particle exposure. Dose delivered by the charged particle increases sharply at the Bragg peak. However, the Bragg curve does not necessarily represent the biological damage along the particle path since biological effects are influenced by the track structures of both primary and secondary particles. Therefore, the ‘‘biological Bragg curve’’ is dependent on the energy and the type of the primary particle and may vary for different biological end points. Measurements of the induction of micronuclei (MN) have made across the Bragg curve in human fibroblasts exposed to energetic silicon and iron ions in vitro at two different energies, 300 MeV/nucleon and 1 GeV/nucleon. Although the data did not reveal an increased yield of MN at the location of the Bragg peak, the increased inhibition of cell progression, which is related to cell death, was found at the Bragg peak location. These results are compared to the calculations of biological damage using a stochastic Monte-Carlo track structure model, Galactic Cosmic Ray Event-based Risk Model (GERM) code (Cucinotta et al., 2011). The GERM code estimates the basic physical properties along the passage of heavy ions in tissue and shielding materials, by which the experimental set-up can be interpreted. The code can also be used to describe the biophysical events of interest in radiobiology, cancer therapy, and space exploration. The calculation has shown that the severely damaged cells at the Bragg peak are more likely to go through reproductive death, the so called “overkill”. F. A. Cucinotta, I. Plante, A. L. Ponomarev, and M. Y. Kim, Nuclear Interactions in Heavy Ion Transport and Event

  11. Heavy Ion Inertial Fusion Energy: Summaries of Program Elements

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, A; Barnard, J J; Kaganovich, I; Seidl, P A; Briggs, R J; Faltens, A; Kwan, J W; Lee, E P; Logan, B G

    2011-02-28

    The goal of the Heavy Ion Fusion (HIF) Program is to apply high-current accelerator technology to IFE power production. Ion beams of mass {approx}100 amu and kinetic energy {>=} 1 GeV provide efficient energy coupling into matter, and HIF enjoys R&D-supported favorable attributes of: (1) the driver, projected to be robust and efficient; see 'Heavy Ion Accelerator Drivers.'; (2) the targets, which span a continuum from full direct to full indirect drive (and perhaps fast ignition), and have metal exteriors that enable injection at {approx}10 Hz; see 'IFE Target Designs'; (3) the near-classical ion energy deposition in the targets; see 'Beam-Plasma Interactions'; (4) the magnetic final lens, robust against damage; see 'Final Optics-Heavy Ion Beams'; and (5) the fusion chamber, which may use neutronically-thick liquids; see 'Liquid-Wall Chambers.' Most studies of HIF power plants have assumed indirect drive and thick liquid wall protection, but other options are possible.

  12. Heavy-ion performance of the LHC and future colliders

    CERN Document Server

    AUTHOR|(SzGeCERN)696614; Stahl, Achim; Jowett, John M

    2015-10-09

    In 2008 the Large Hadron Collider (LHC) and its experiments started operation at the European Centre of Nuclear Research (CERN) in Geneva with the main aim of finding or excluding the Higgs boson. Only four years later, on the 4th of July 2012, the discovery of a Higgs-like particle was proven and first published by the two main experiments ATLAS and CMS. Even though proton–proton collisions are the main operation mode of the LHC, it also acts as an heavy-ion collider. Here, the term “heavy-ion collisions” refers to the collision between fully stripped nuclei. While the major hardware system of the LHC is compatible with heavy-ion operation, the beam dynamics and performance limits of ion beams are quite different from those of protons. Because of the higher mass and charge of the ions, beam dynamic effects like intra-beam scattering and radiation damping are stronger. Also the electromagnetic cross-sections in the collisions are larger, leading to significantly faster intensity decay and thus shorter l...

  13. Preliminary results from the heavy ions in space experiment

    Science.gov (United States)

    Adams, James H., Jr.; Beahm, Lorraine P.; Tylka, Allan J.

    1992-01-01

    The Heavy Ions In Space (HIIS) experiment has two primary objectives: (1) to measure the elemental composition of ultraheavy galactic cosmic rays, beginning in the tin-barium region of the periodic table; and (2) to study heavy ions which arrive at LDEF below the geomagnetic cutoff, either because they are not fully stripped of electrons or because their source is within the magnetosphere. Both of these objectives have practical as well as astrophysical consequences. In particular, the high atomic number of the ultraheavy galactic cosmic rays puts them among the most intensely ionizing particles in Nature. They are therefore capable of upsetting electronic components normally considered immune to such effects. The below cutoff heavy ions are intensely ionizing because of their low velocity. They can be a significant source of microelectronic anomalies in low inclination orbits, where Earth's magnetic field protects satellites from most particles from interplanetary space. The HIIS results will lead to significantly improved estimates of the intensely ionizing radiation environment.

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

    NARCIS (Netherlands)

    Abelev, B.I.; Bai, Y.; Botje, M.A.J.; Braidot, E; Snellings, R.J.M.; Mischke, A.; van Leeuwen, M.; Russcher, M.J.; Peitzmann, T.; Benedosso, F.

    2009-01-01

    We present results for the measurement of ϕ meson production via its charged kaon decay channel ϕ→K+K- in Au+Au collisions at √sNN=62.4,130, and 200 GeV, and in p+p and d+Au collisions at √sNN=200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (|y|

  15. Heavy ion irradiation effects of polymer film on absorption of light

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Noboru; Seguchi, Tadao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Arakawa, Tetsuhito

    1997-03-01

    Ion irradiation effects on the absorption of light for three types of polymer films; polyethylene-terephthalate (PET), polyethylene-naphthalate (PEN), and polyether-ether-ketone (PEEK) were investigated by irradiation of heavy ions with Ni{sup 4+}(15MeV), O{sup 6+}(160MeV), and Ar{sup 8+}(175MeV), and compared with electron beams(EB) irradiation. The change of absorption at 400nm by a photometer was almost proportional to total dose for ions and EB. The absorption per absorbed dose was much high in Ni{sup 4+}, but rather small in O{sup 6+} and Ar{sup 8+} irradiation, and the absorption by EB irradiation was accelerated by the temperature of polymer film during irradiation. The beam heating of materials during ion irradiation was assumed, especially for Ni ion irradiation. The heavy ion irradiation effect of polymers was thought to be much affected by the ion beam heating than the linear energy transfer(LET) of radiation source. (author)

  16. Studies of low-energy heavy-ion reactions at LNL

    Energy Technology Data Exchange (ETDEWEB)

    Stefanini, A.M.; Ackermann, D.; Corradi, L.; He, J.H. [Istituto Nazionale di Fisica Nucleare, Legnaro (Italy); Beghini, S.; Montagnoli, G.; Scarlassara, F.; Segato, G.P. [Istituto Nazionale di Fisica Nucleare, Padua (Italy)

    1995-02-01

    Recent experimental investigations on low-energy heavy-ion reaction dynamics performed at Legnaro are reviewed. A short description is given of the setup which enables the study of elastic scattering and of quasielastic transfer reactions, as well as of fusion reactions. After a brief hint on the perspectives in the field of multinucleon transfer, the main part of the lecture is dedicated to the fusion reactions for which recent developments, like the studies of barrier distributions and the theoretical approach using the Interaction Boson Model, have lead to a renewed interest. Some results obtained by our group are presented for the system {sup 32}S+ {sup 58,64}Ni, {sup 16}O+{sup 194}Pt (sensitivity to the target deformation) and {sup 58}Ni+{sup 60}Ni (evidence for multiphonon excitation in subbarrier fusion). (author). 24 refs, 8 figs.

  17. PREFACE: Heavy-Ion Spectroscopy and QED Effects in Atomic Systems

    Science.gov (United States)

    Lindgren, Ingvar; Martinson, Indrek; Schuch, Reinhold

    1993-01-01

    now essentially solved. The experimental accuracy is already so high that also higher-order QED effects become observable, and several groups are now active in trying to evaluate such effects from first principles. Another related field where substantial progress has recently been made involves precision measurements of X-ray transitions. This has created an interest in the study of deep inner holes in heavy atoms, where large relativistic and QED effects appear. These effects are as large as in corresponding highly charged ions, but the interpretation requires that the many-body effects from the surrounding electrons are accurately extracted. This is a big challenge at present. Atomic collision physics with highly charged ions has been dominated in recent years by the search for a possibility to describe electron-electron interaction within the dynamics of collisions. The experiments on multielectron transfer reactions with highly charged ions posed in this respect quite a challenge to the theory. The models developed to meet this were often based on methods and terminologies developed for describing the inter-electronic interactions in atomic structure. This caused many controversial discussions, also during this symposium. A new and fast rising field is the interaction of highly charged ions with solid surfaces. This may become an important link between atomic physics and condensed-matter physics, stimulated by the opportunity to study effects in coupled many-body systems present in the case when a large amount of electrons is transferred from the solid to each single ion. Furtheron, collision experiments with cooled ion beams in ion storage rings open new dimensions also for atomic spectroscopy. It appears possible that transition and binding energies can be measured in recombination of very heavy ions with a better quality than by conventional Auger electron or X-ray spectroscopy. Obviously, it is not possible to cover all the fields mentioned here in a single

  18. An abrasion-ablation model description of galactic heavy-ion fragmentation

    Science.gov (United States)

    Townsend, L. W.; Wilson, J. W.; Norbury, J. W.; Bidasaria, H. B.

    1984-01-01

    The fragmentation of high-energy galactic heavy ions by nuclear interactions with arbitrary target nuclei is described within the context of a simple abrasion-ablation fragmentation model. The abrasion part of the theory utilizes a quantum-mechanical formalism based upon an optical model potential approximation to the exact nucleus-nucleus multiple-scattering series. Nuclear charge distributions of the excited prefragments are calculated using either a hypergeometric distribution or a method based upon the zero-point oscillations of the giant dipole resonance. The excitation energy of the prefragment is estimated from the geometric clean-cut abrasion-ablation model. The decay probabilities for the various particle emission channels, in the ablation stage of the fragmentation, are obtained from the EVAP-4 Monte Carlo computer program. Elemental production cross sections for 1.88-GeV/nucleon iron colliding with carbon, silver, and lead targets are calculated and compared with experimental data and with the predictions from the semiempirical relations of Silberberg and Tsao.

  19. Measurements of Upsilon meson suppression in heavy ion collisions with the CMS experiment at the LHC

    CERN Document Server

    Filipovic, Nicolas

    Measurements of Upsilon suppression in ultra relativistic heavy ion collisions are key to understanding the hot and deconfined phase of matter called Quark-Gluon Plasma (QGP). The cross section of Upsilon states Y(nS) are measured in proton-proton collisions and in lead-lead collisions at the centre-of-mass energy of 2.76 TeV per nucleon pair. Individual states are measured through their dimuon decay channel using the Compact Muon Solenoid (CMS) at CERN. The cross sections measured in pp and PbPb are compared thanks to the nuclear modification factor, $R_{AA}$. This observable is computed for Upsilon(1S) and Upsilon(2S) in several bins of transverse momentum,rapidity and centrality of the collision. An upper limit on the production of Upsilon(3S) in PbPb is estimated. These measurements exhibit a clear and ordered suppression pattern, consistent with the hypothesis of sequential melting of quarkonia in the QGP. The measured Upsilon(1S) and Upsilon(2S) suppressions are observed to be independent of transverse ...

  20. Radiation protection and environmental management at the relativistic heavy ion collider.

    Science.gov (United States)

    Musolino, S V; Briggs, S L; Stevens, A J

    2001-01-01

    The Relativistic Heavy Ion Collider (RHIC) is a high energy hadron accelerator built to study basic nuclear physics. It consists of two counter-rotating beams of fully stripped gold ions that are accelerated in two rings to an energy of 100 GeV/nucleon or protons at 250 GeV/c. The beams can be stored for a period of five to ten hours and brought into collision for experiments during that time. The first major physics objective is to recreate a state of matter, the quark-gluon plasma, that has been predicted to have existed at a short time after the creation of the universe. Because there are only a few other high energy particle accelerators like RHIC in the world, the rules promulgated in the US Code of Federal Regulations under the Atomic Energy Act, State regulations, or international guidance documents do not cover prompt radiation from accelerators to govern directly the design and operation of a superconducting collider. Special design criteria for prompt radiation were developed to provide guidance tor the design of radiation shielding. Environmental Management at RHIC is accomplished through the ISO 14001 Environmental Management System. The applicability, benefits, and implementation of ISO 14001 within the framework of a large research accelerator complex are discussed in the paper.

  1. Ultra-peripheral heavy-ion collisions with the CMS experiment

    Directory of Open Access Journals (Sweden)

    2017-01-01

    Full Text Available Ultraperipheral collisions (UPCs of heavy ions involve long range electromagnetic interactions at impact parameters larger than sum of their radii where hadronic interaction is largely suppressed and the exchanged photon materializes into qq(bar bound state after interacting with the gluonic field of the target proton or ion. Photoproduction of heavy vector mesons (J/psi, Upsilon thus provide direct information on the gluon distribution functions in the nucleon/nucleus at very low values of Bjorken-x. The CMS experiment has excellent capabilities for the measurement of the heavy vector mesons in the dimuon decay channel using the tracker and the muon chambers. The measured coherent J/psi photoproduction cross section in ultraperipheral Pb-Pb collisions using 2011 PbPb data and Upsilon photoproduction in ultraperipheral pPb collisions during 2013, will be presented. The prospects for future measurements using the data collected in the 2015 PbPb run will also be described.

  2. Low and high dose rate heavy ion radiation-induced intestinal and colonic tumorigenesis in APC1638N/+ mice

    Science.gov (United States)

    Suman, Shubhankar; Kumar, Santosh; Moon, Bo-Hyun; Fornace, Albert J.; Datta, Kamal

    2017-05-01

    Ionizing radiation (IR) is a recognized risk factor for colorectal cancer (CRC) and astronauts undertaking long duration space missions are expected to receive IR doses in excess of permissible limits with implications for colorectal carcinogenesis. Exposure to IR in outer space occurs at low doses and dose rates, and energetic heavy ions due to their high linear energy transfer (high-LET) characteristics remain a major concern for CRC risk in astronauts. Previously, we have demonstrated that intestinal tumorigenesis in a mouse model (APC1638N/+) of human colorectal cancer was significantly higher after exposure to high dose rate energetic heavy ions relative to low-LET γ radiation. The purpose of the current study was to compare intestinal tumorigenesis in APC1638N/+ mice after exposure to energetic heavy ions at high (50 cGy/min) and relatively low (0.33 cGy/min) dose rate. Male and female mice (6-8 weeks old) were exposed to either 10 or 50 cGy of 28Si (energy: 300 MeV/n; LET: 70 keV/μm) or 56Fe (energy: 1000 MeV/n; LET: 148 keV/μm) ions at NASA Space Radiation Laboratory in Brookhaven National Laboratory. Mice (n = 20 mice/group) were euthanized and intestinal and colon tumor frequency and size were counted 150 days after radiation exposure. Intestinal tumorigenesis in male mice exposed to 56Fe was similar for high and low dose rate exposures. Although male mice showed a decreasing trend at low dose rate relative to high dose rate exposures, the differences in tumor frequency between the two types of exposures were not statistically significant after 28Si radiation. In female mice, intestinal tumor frequency was similar for both radiation type and dose rates tested. In both male and female mice intestinal tumor size was not different after high and low dose rate radiation exposures. Colon tumor frequency in male and female mice after high and low dose rate energetic heavy ions was also not significantly different. In conclusion, intestinal and colonic tumor

  3. The Mesozoic Era of relativistic heavy ion physics and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Harris, J.W.

    1994-03-01

    In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 {times} 10{sup 12} {degrees}K evolved to become today`s Universe, the goal of relativistic and ultra-relativistic heavy ion physics is to understand the equation of state of nuclear, hadronic and partonic matter. This quest is of cross-disciplinary interest. The phase transition from partonic matter to hadronic matter tens of micro-seconds after the beginning of the universe is of interest to cosmology. Fluctuations during this phase transition would influence nucleosynthesis and the understanding of baryonic inhomogeneities in the universe. The nuclear matter equation of state, which describes the incompressibility of nuclear matter, governs neutron star stability. It determines the possible existence of strange quark matter stars and the dynamics of supernova expansion in astrophysics. The existence of collective nuclear phenomena in nuclear physics is also determined by the nuclear equation of state. In relativistic heavy ion collisions collective nuclear flow has been observed and is being studied extensively to obtain a better understanding of the incompressibility of nuclear matter. In high energy nuclear and particle physics, production and excitations of hadronic final states have been studied in detail and are important to an overall understanding of the equation of state of nuclear matter at finite temperature. The possibility in ultra-relativistic heavy ion collisions to create and study highly excited hadronic and partonic degrees of freedom provides a unique opportunity for understanding the behavior of nuclear, hadronic and partonic matter. Study of the QCD vacuum, of particular interest in particle physics, would provide a better understanding of symmetry-breaking mechanisms and the origins of the masses of the various quarks and particles.

  4. Isotropization and hydrodynamization in weakly coupled heavy-ion collisions

    CERN Document Server

    Kurkela, Aleksi

    2015-01-01

    We numerically solve 2+1D effective kinetic theory of weak coupling QCD under longitudinal expansion relevant for early stages of heavy-ion collisions. We find agreement with viscous hydrodynamics and classical Yang-Mills simulations in the regimes where they are applicable. By choosing initial conditions that are motivated by color-glass-condensate framework we find that for Q=2GeV and $\\alpha_s$=0.3 the system is approximately described by viscous hydrodynamics well before $\\tau \\lesssim 1.0$ fm/c.

  5. Status report on the Holifield Heavy Ion Research Facility

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.; Alton, G.D.; Ball, J.B.; Benjamin, J.A.; Biggerstaff, J.A.; Erb, K.A.; Hudson, E.D.; Juras, R.C.; Kloeppel, P.K.; Lord, R.S. (Oak Ridge National Lab., TN (USA))

    1984-02-15

    The Holifield Heavy Ion Research Facility has been in routine operation since July, 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we will discuss the status of the tandem accelerator and some aspects of our experience with coupled operation.

  6. Status report on the holifield heavy ion research facility

    Science.gov (United States)

    Jones, C. M.; Alton, G. D.; Ball, J. B.; Benjamin, J. A.; Biggerstaff, J. A.; Erb, K. A.; Hudson, E. D.; Juras, R. C.; Kloeppel, P. K.; Lord, R. S.; Ludemann, C. A.; Mann, J. E.; Martin, J. A.; Mosko, S. W.; Richardson, E. G.; Sayer, R. O.; Ziegler, N. F.

    1984-02-01

    The Holifield Heavy Ion Research Facility has been in routine operation since July, 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we will discuss the status of the tandem accelerator and some aspects of our experience with coupled operation.

  7. New beam for the CERN fixed target heavy ion programme

    CERN Document Server

    Hill, C E; O'Neill, M

    2002-01-01

    The physicists of the CERN heavy ion community (SPS fixed target physics) have requested lighter ions than the traditional lead ions, to scale their results and to check their theories. Studies have been carried out to investigate the behaviour of the ECR4 for the production of an indium beam. Stability problems and the low melting point of indium required some modifications to the oven power control system which will also benefit normal lead ion production. Present results of the source behaviour and the ion beam characteristics will be presented.

  8. Medical applications of nuclear physics and heavy-ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Jose R.

    2000-08-01

    Isotopes and accelerators, hallmarks of nuclear physics, are finding increasingly sophisticated and effective applications in the medical field. Diagnostic and therapeutic uses of radioisotopes are now a $10B/yr business worldwide, with over 10 million procedures and patient studies performed every year. This paper will discuss the use of isotopes for these applications. In addition, beams of protons and heavy ions are being more and more widely used clinically for treatment of malignancies. To be discussed here as well will be the rationale and techniques associated with charged-particle therapy, and the progress in implementation and optimization of these technologies for clinical use.

  9. Studies on stochastic cooling of heavy ions in the LHC

    CERN Document Server

    Schaumann, M; Salvant, B; Wendt, M; Blaskiewicz, M; Verdú-Andrés, S

    2014-01-01

    Future high luminosity heavy-ion operation of the LHC will be dominated by very rapid luminosity decay due to the large collision cross-section and, to a lesser extent, emittance growth from intra-beam scattering (IBS) due to the high bunch intensities. A stochastic cooling system could reduce the emittance far below its initial value and reduce the losses from debunching during collisions, allowing more of the initial beam intensity to be converted into integrated luminosity before the beams are dumped. We review the status of this proposal, system and hardware properties and potential locations for the equipment in the tunnel.

  10. Data acquisition for the HILI (Heavy Ion Light Ion) detector

    Energy Technology Data Exchange (ETDEWEB)

    Teh, K.M.; Shapira, D.; McConnell, J.W.; Kim, H.; Novotny, R.

    1987-01-01

    A large acceptance, multi-segmented detector system capable of the simultaneous detection of heavy and light ions has been constructed. The heavy ions are detected with a segmented gas ionization chamber and a multiwire proportional counter while the light ions are detected with a 192 element plastic phoswich hodoscope. Processing the large number of signals is accomplished through a combination of CAMAC and FASTBUS modules and preprocessors, and a Host minicomputer. Details of the data acquisition system and the reasons for adopting a dual standards system are discussed. In addition, a technique for processing signals from an individual hodoscope detector is presented. 4 refs., 3 figs.

  11. Heavy-ion reactions at the GSI Darmstadt

    Energy Technology Data Exchange (ETDEWEB)

    Metag, V. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Giessen Univ. (Germany). 2. Physikalisches Inst.

    1998-12-01

    In nucleus-nucleus collisions at bombarding energies on the order of 1 AGeV nuclear matter can be compressed to similar densities as encountered in stellar processes, i.e. to 2-3 times normal density. Experimental data providing information on the space-time evolution of these collisions are presented: the properties of hadrons in the hot and compressed nuclear medium in the high-density phase, collective flow phenomena during the expansion phase, and the hadrochemical composition of the collision system in the final stage of the reaction at freeze-out are discussed. Future directions in the heavy-ion reaction program are indicated. (orig.)

  12. Dilepton radiation and bulk viscosity in heavy-ion collisions

    Science.gov (United States)

    Vujanovic, Gojko; Paquet, Jean-François; Shen, Chun; Denicol, Gabriel S.; Jeon, Sangyong; Gale, Charles; Heinz, Ulrich

    2017-08-01

    Starting from IP-Glasma initial conditions, we investigate the effects of bulk pressure on thermal dilepton production at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) energies. Though results of the thermal dilepton v2 under the influence of both bulk and shear viscosity is presented for top RHIC energy, more emphasis is put on LHC energy where such a calculation is computed for the first time. The effects of the bulk pressure on thermal dilepton v2 at the LHC are explored through bulk-induced modifications on the dilepton yield.

  13. Dynamical description of heavy-ion collisions at Fermi energies

    Directory of Open Access Journals (Sweden)

    Napolitani P.

    2016-01-01

    Full Text Available Descriptions of heavy-ion collisions at Fermi energies require to take into account in-medium dissipation and phase-space fluctuations. The interplay of these correlations with the one-body collective behaviour determines the properties (kinematics and fragment production and the variety of mechanisms (from fusion to neck formation and multifragmentation of the exit channel. Starting from fundamental concepts tested on nuclear matter, we build up a microscopic description which addresses finite systems and applies to experimental observables.

  14. Initial operation of the Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K. W.

    1979-01-01

    Initial operation and recent development of the Argonne superconducting heavy-ion linac are discussed. The linac has been developed in order to demonstrate a cost-effective means of extending the performance of electrostatic tandem accelerators. The results of beam acceleration tests which began in June 1978 are described. At present 7 of a planned array of 22 resonators are operating on-line, and the linac system provides an effective accelerating potential of 7.5 MV. Although some technical problems remain, the level of performance and reliability is sufficient that appreciable beam time is becoming available to users.

  15. Influence of heavy ion implantation on the microhardness of lif

    CERN Document Server

    Abu-Alazm, S M

    2003-01-01

    The paper presented microhardness measurements for pure lithium fluoride (LiF) implanted with Ar, Kr and Xe at doses ranged from 10 sup 9 up to 10 sup 1 2 ion/cm sup 2. Measurements were also performed for the microhardness after irradiation by electron and gamma rays. The data exhibited a large increase of microhardness of LiF using heavy ions in comparison with the unimplanted and irradiated samples with electrons and gamma rays. The influence of annealing the samples on the microhardness is also studied. The obtained results were interpreted according to the formation of F-centers in LiF.

  16. A search for quarks produced in heavy-ion interactions

    CERN Multimedia

    2002-01-01

    We propose to search for free fractional charges produced in 225~GeV/A heavy-ion collisions at the SPS. A tank of mercury placed in the NA38 beam stop will serve both as a production target and as an absorber to stop reaction products. Mercury from the tank will subsequently be distilled.\\\\ \\\\ This process will decrease the amount of mercury that has to be processed by a factor of about $10^{5}$. The concentrate will be searched for quarks using the proven SFSU automated Millikan apparatus.\\\\ \\\\ This experiment will be sensitive to about one quark produced per $2 \\times 10^{8}$ beam particles.

  17. High Current Ion Sources and Injectors for Heavy Ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Kwan, Joe W.

    2005-02-15

    Heavy ion beam driven inertial fusion requires short ion beam pulses with high current and high brightness. Depending on the beam current and the number of beams in the driver system, the injector can use a large diameter surface ionization source or merge an array of small beamlets from a plasma source. In this paper, we review the scaling laws that govern the injector design and the various ion source options including the contact ionizer, the aluminosilicate source, the multicusp plasma source, and the MEVVA source.

  18. Studies in High Energy Heavy Ion Nuclear Physics

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Gerald W. [Univ. of Texas, Austin, TX (United States); Markert, Christina [Univ. of Texas, Austin, TX (United States)

    2016-09-01

    This close-out report covers the period 1994 - 2015 for DOE grant DE-FG02-94ER40845 with the University of Texas at Austin. The research was concerned with studies of the strong nuclear force and properties of nuclear matter under extreme conditions of temperature and density which far exceed that in atomic nuclei. Such extreme conditions are briefly created (for about 10 trillionths of a trillionth of a second) during head-on collisions of large atomic nuclei (e.g. gold) colliding at speeds very close to the speed-of-light. The collisions produce thousands of subatomic particles, many of which are detected in our experiment called STAR at the Relativistic Heavy-Ion Collider at the Brookhaven National Lab in New York. The goal of our research is to learn how the strong nuclear force and its fundamental particles (quarks and gluons) behave in extreme conditions similar to that of the early Universe when it was about 1 micro-second old, and in the cores of very dense neutron stars. To learn anything new about the matter which exists for such a very short amount of time requires carefully designed probes. In our research we focused on two such probes, one being short-lived resonance particles and the other using correlations between pairs of the detected particles. Resonances are short-lived particles created in the collision, which interact with the surrounding matter, and which break apart, or "decay" into more stable particles which survive long enough to be seen in our detectors. The dependence of resonance properties on the conditions in the collision system permit tests of theoretical models and improve our understanding. Dynamical interactions in the matter also leave imprints on the final, outgoing particle distributions measured in the experiment. In particular, angular correlations between pairs of particles can be related to the fundamental strong force as it behaves in the hot, dense matter. Studying correlations as a function of experimentally controlled

  19. Nucleon correlations and the structure of Zn413071

    Directory of Open Access Journals (Sweden)

    S. Bottoni

    2017-12-01

    Full Text Available The structure of 71Zn was investigated by one-neutron transfer and heavy-ion induced complex (deep-inelastic reactions using the GRETINA-CHICO2 and the Gammasphere setups, respectively. The observed inversion between the 9/2+ and 1/2− states is explained in terms of the role of neutron pairing correlations. Non-collective sequences of levels were delineated above the 9/2+ isomeric state. These are interpreted as being associated with a modest oblate deformation in the framework of Monte-Carlo shell-model calculations carried out with the A3DA-m Hamiltonian in the pfg9/2d5/2 valence space. Similarities with the structure of Ni402868 were observed and the shape-coexistence mechanism in the N=40 region of neutron-rich nuclei is discussed in terms of the so-called Type-II shell evolution, with an emphasis on proton–neutron correlations between valence nucleons, especially those involving the shape-driving g9/2 neutron orbital.

  20. Photon annd pion production in heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Blann, M.

    1989-05-01

    In this paper we describe different formulations for treating the nucleon-nucleon transport physics. These will all be semi-classical treatments; however considerable work has been done considering the relationship between quantal and semi-classical formulations. We discuss additional input specific to calculation of pion and photon yields, and present comparisons between calculated and experimental results, mostly for high energy photons. Conclusions and suggestions for future work are presented in the last section. 65 refs., 7 figs.

  1. Search for proton emission in {sup 54}Ni and multi-nucleon transfer reactions in the actinide region

    Energy Technology Data Exchange (ETDEWEB)

    Geibel, Kerstin

    2012-06-15

    The first part of the thesis presents the investigation of fusion-evaporation reactions in order to verify one-proton emission from the isomeric 10{sup +} state in the proton rich nucleus {sup 54}Ni. Between the years 2006 and 2009 a series of experimental studies were performed at the Tandem accelerator in the Institut fuer Kernphysik (IKP), University of Cologne. These experiments used fusion-evaporation reactions to populate {sup 54}Ni via the two-neutron-evaporation channel of the compound nucleus {sup 56}Ni. The cross section for the population of the ground state of {sup 54}Ni was predicted to be in orders of microbarn. This required special care with respect to the sensitivity of the experimental setup, which consisted of a double-sided silicon-strip detector (DSSSD), a neutron-detector array and HPGe detectors. In two experiments the excitation functions of the reactions ({sup 32}S+{sup 24}Mg) and ({sup 28}Si+{sup 28}Si) were determined to find the optimal experimental conditions for the population of {sup 54}Ni. A final experiment employed a {sup 28}Si beam at an energy of 70 MeV, impinging on a {sup 28}Si target. With a complex analysis it is possible to obtain a background-free energy spectrum of the DSSSD. An upper cross section limit for the population of the 10{sup +} state in {sup 54}Ni is established at σ({sup 54}Ni(10{sup +})) ≤ (13.9 ± 7.8) nbarn. In the second part of the thesis the population of actinide nuclei by multi-nucleon transfer reactions is investigated. Two experiments, performed in 2007 and 2008 at the CLARA-PRISMA setup at the Laboratori Nazionali di Legnaro, are analyzed with respect to the target-like reaction products. In both experiments {sup 238}U was used as target. A {sup 70}Zn beam with 460 MeV and a {sup 136}Xe beam with 926 MeV, respectively, impinged on the target, inducing transfer reactions. Kinematic correlations between the reaction partners are used to obtain information on the unobserved target-like reaction

  2. Modeling of single event gate rupture in power MOSFETs under heavy ion irradiation

    Science.gov (United States)

    Useinov, R. G.; Zebrev, G. I.; Emelyanov, V. V.; Vatuev, A. S.

    2014-12-01

    Destructive single event gate rupture (SEGR) occurring in the gate oxides of power MOSFETs under impact of heavy ions is studied and modeled. SEGR cross section of power MOSFET with 70 nm oxide thickness as function of gate voltage was measured for four types of heavy ions. A predictive formula for the SEGR cross section is derived and validated. This formula can be used as a predictive instrument for computation of survival probability in a given spectrum of heavy ions in space environments.

  3. Overview of Particle and Heavy Ion Transport Code System PHITS

    Science.gov (United States)

    Sato, Tatsuhiko; Niita, Koji; Matsuda, Norihiro; Hashimoto, Shintaro; Iwamoto, Yosuke; Furuta, Takuya; Noda, Shusaku; Ogawa, Tatsuhiko; Iwase, Hiroshi; Nakashima, Hiroshi; Fukahori, Tokio; Okumura, Keisuke; Kai, Tetsuya; Chiba, Satoshi; Sihver, Lembit

    2014-06-01

    A general purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS, is being developed through the collaboration of several institutes in Japan and Europe. The Japan Atomic Energy Agency is responsible for managing the entire project. PHITS can deal with the transport of nearly all particles, including neutrons, protons, heavy ions, photons, and electrons, over wide energy ranges using various nuclear reaction models and data libraries. It is written in Fortran language and can be executed on almost all computers. All components of PHITS such as its source, executable and data-library files are assembled in one package and then distributed to many countries via the Research organization for Information Science and Technology, the Data Bank of the Organization for Economic Co-operation and Development's Nuclear Energy Agency, and the Radiation Safety Information Computational Center. More than 1,000 researchers have been registered as PHITS users, and they apply the code to various research and development fields such as nuclear technology, accelerator design, medical physics, and cosmic-ray research. This paper briefly summarizes the physics models implemented in PHITS, and introduces some important functions useful for specific applications, such as an event generator mode and beam transport functions.

  4. Search for nuclei in heavy ion collisions at ultrarelativistic energies

    CERN Multimedia

    2002-01-01

    We would like to know if nuclei are still present after a collision of two heavy ions at ultrarelativistic energies. If one can detect some of them at large angle $(>10^{\\circ}-15^{\\circ})$ they very likely come from a multifragmentation of the excited target spectators. Such a multifragmentation in several nuclei has been in proton induced reactions at Fermilab and it was interpreted as a gas-liquid phase transition in nuclei matter near the critical point. With heavy ions the energy deposited in the target spectators will be much higher than in the case of protons and a different mechanism should be involved if nuclei are still observed. \\\\ \\\\ We propose to detect nuclei using 1-2 silicon telescopes and a 1-2mg/cm$^{2}$ Au target bombarded by an $^{16}$O or $^{32}$S beam at 226 GeV/u. The set-up will be installed in a small cube located just before the NA38 experiment and should not perturb it.\\\\ \\\\ Data from $^{16}$O incident on Au have been taken last year. The experiment is presently taking data with $^{...

  5. Dislocation loop formation by swift heavy ion irradiation of metals

    Science.gov (United States)

    Khara, Galvin S.; Murphy, Samuel T.; Duffy, Dorothy M.

    2017-07-01

    A coupled two-temperature, molecular dynamics methodology is used to simulate the structural evolution of bcc metals (Fe and W) and fcc metals (Cu and Ni) following irradiation by swift heavy ions. Electronic temperature dependent electronic specific heat capacities and electron-phonon coupling strengths are used to capture the full effects of the variation in the electronic density of states. Tungsten is found to be significantly more resistant to damage than iron, due both to the higher melting temperature and the higher thermal conductivity. Very interesting defect structures, quite different from defects formed in cascades, are found to be created by swift heavy ion irradiation in the bcc metals. Isolated vacancies form a halo around elongated interstitial dislocation loops that are oriented along the ion path. Such configurations are formed by rapid recrystallization of the molten cylindrical region that is created by the energetic ion. Vacancies are created at the recrystallization front, resulting in excess atoms at the core which form interstitial dislocation loops on completion of crystallization. These unique defect structures could, potentially, be used to create metal films with superior mechanical properties and interesting nanostructures.

  6. Characterization of swift heavy ion irradiation damage in ceria

    Energy Technology Data Exchange (ETDEWEB)

    Yablinsky, Clarissa; Devanathan, Ram; Pakarinen, Janne; Gan, Jian; Severin, Daniel; Trautmann, Christina; Allen, T. R.

    2015-05-14

    We have examined microstructural evolution in irradiated ceria (CeO2) using swift heavy ion irradiation, electron microscopy, and atomistic simulation. CeO2, a UO2 fuel surrogate, was irradiated with gold ions at an energy of 1 GeV to fluences up to 1x1014 ions/cm2. Transmission electron microscopy accompanied by electron energy loss spectroscopy showed that the ion tracks were of similar size at all fluences, and that there was no chemical change in the ion track core. Classical molecular dynamics simulations of thermal spikes in CeO2 with energy deposition of 12 and 36 keV/nm show damage consisting of isolated point defects at the lower energy and defect clusters at 36 keV/nm, with no amorphization at either energy. Inferences are drawn from modeling about density changes in the ion track and the formation of interstitial loops that shed light on features observed by electron microscopy of swift heavy ion irradiated ceria.

  7. Characterization of swift heavy ion irradiation damage in ceria

    Energy Technology Data Exchange (ETDEWEB)

    Yablinsky, Clarissa A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Devanathan, Ram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pakarinen, Janne [Inst. for Nuclear Research Center (SCK-CEN), Mol, (Belgium); Gan, Jian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Severin, Daniel [GSI-Darmstadt (Germany); Trautmann, Christina [GSI-Darmstadt (Germany); Allen, Todd R. [Univ. of Wisconsin, Madison, WI (United States). Energy Physics Dept.

    2015-03-04

    Swift heavy ion induced radiation damage is investigated for ceria (CeO2), which serves as a UO2 fuel surrogate. Microstructural changes resulting from an irradiation with 940 MeV gold ions of 42 keV/nm electronic energy loss are investigated by means of electron microscopy accompanied by electron energy loss spectroscopy showing that there exists a small density reduction in the ion track core. While chemical changes in the ion track are not precluded, evidence of them was not observed. Classical molecular dynamics simulations of thermal spikes in CeO2 with an energy deposition of 12 and 36 keV/nm show damage consisting of isolated point defects at 12 keV/nm, and defect clusters at 36 keV/nm, with no amorphization at either energy. Inferences are drawn from modeling about density changes in the ion track and the formation of interstitial loops that shed light on features observed by electron microscopy of swift heavy ion irradiated ceria.

  8. Heavy flavour production at CMS in heavy ion collisions

    CERN Document Server

    Nguyen, Matthew

    2015-01-01

    We review recent results relating to beauty production in heavy-ion collisions, in both the closed and open heavy flavor sectors, from the CMS experiment at the LHC. The sequential suppression of the ° states in PbPb collisions is thought to be evidence of the dissociation of quarkonia bound states in deconfined matter. Data from pPb collisions demonstrate that while cold nuclear effects appear to be subdominant in minimum bias collisions, there exists a non-trivial dependence on collision multiplicity that remains to be understood. The suppression of high p T particles in heavy-ion collisions, relative to the expectation from pp collisions, is typically interpreted in terms of energy loss of hard scattered parton in the dense nuclear medium. The flavor dependence of the energy loss may be accessed via measurements of b hadrons and b-tagged jets. Measurement of B mesons, via non-prompt J = y , at relatively low p T indicate a smaller suppression factor than D meson or inclusive charged hadrons. Data on b jet...

  9. Anti-biofilm activity of Fe heavy ion irradiated polycarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, R.P. [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Hareesh, K., E-mail: appi.2907@gmail.com [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Bankar, A. [Department of Microbiology, Waghire College, Pune 412301 (India); Sanjeev, Ganesh [Microtron Centre, Department of Studies in Physics, Mangalore University, Mangalore 574166 (India); Asokan, K.; Kanjilal, D. [Inter University Accelerator Centre, Arun Asaf Ali Marg, New Delhi 110067 (India); Dahiwale, S.S.; Bhoraskar, V.N. [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Dhole, S.D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

    2016-10-01

    Highlights: • PC films were irradiated by 60 and 120 MeV Fe ions. • Irradiated PC films showed changes in its physical and chemical properties. • Irradiated PC also showed more anti-biofilm activity compared to pristine PC. - Abstract: Polycarbonate (PC) polymers were investigated before and after high energy heavy ion irradiation for anti-bacterial properties. These PC films were irradiated by Fe heavy ions with two energies, viz, 60 and 120 MeV, at different fluences in the range from 1 × 10{sup 11} ions/cm{sup 2} to 1 × 10{sup 13} ions/cm{sup 2}. UV-Visible spectroscopic results showed optical band gap decreased with increase in ion fluences due to chain scission mainly at carbonyl group of PC which is also corroborated by Fourier transform infrared spectroscopic results. X-ray diffractogram results showed decrease in crystallinity of PC after irradiation which leads to decrease in molecular weight. This is confirmed by rheological studies and also by differential scanning calorimetric results. The irradiated PC samples showed modification in their surfaces prevents biofilm formation of human pathogen, Salmonella typhi.

  10. Modeling chamber transport for heavy-ion fusion

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-10-01

    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.

  11. Solar wind heavy ions from energetic coronal events

    Energy Technology Data Exchange (ETDEWEB)

    Bame, S.J.

    1978-01-01

    Ions heavier than those of He can be resolved in the solar wind with electrostatic E/q analyzers when the local thermal temperatures are low. Ordinarily this condition prevails in the low speed solar wind found between high speed streams, i.e. the interstream, IS, solar wind. Various ions of O, Si and Fe are resolved in IS heavy ion spectra. Relative ion peak intensities indicate that the O ionization state is established in the IS coronal source regions at approx. 2.1 x 10/sup 6/K while the state of Fe is frozen in at approx. 1.5 x 10/sup 6/K farther out. Occasionally, anomalous spectra are observed in which the usually third most prominent ion peak, O/sup 8 +/, is depressed as are the Fe peaks ranging from Fe/sup 12 +/ to Fe/sup 7 +/. A prominent peak in the usual Si/sup 8 +/ position of IS spectra is self-consistently shown to be Fe/sup 16 +/. These features demonstrate that the ionization states were frozen in at higher than usual coronal temperatures. The source regions of these hot heavy ion spectra are identified as energetic coronal events including flares and nonflare coronal mass ejections. 24 references.

  12. Uniformity of fuel target implosion in Heavy Ion Fusion

    CERN Document Server

    Kawata, S; Suzuki, T; Karino, T; Barada, D; Ogoyski, A I; Ma, Y Y

    2015-01-01

    In inertial confinement fusion the target implosion non-uniformity is introduced by a driver beams' illumination non-uniformity, a fuel target alignment error in a fusion reactor, the target fabrication defect, et al. For a steady operation of a fusion power plant the target implosion should be robust against the implosion non-uniformities. In this paper the requirement for the implosion uniformity is first discussed. The implosion uniformity should be less than a few percent. A study on the fuel hotspot dynamics is also presented and shows that the stagnating plasma fluid provides a significant enhancement of vorticity at the final stage of the fuel stagnation. Then non-uniformity mitigation mechanisms of the heavy ion beam (HIB) illumination are also briefly discussed in heavy ion inertial fusion (HIF). A density valley appears in the energy absorber, and the large-scale density valley also works as a radiation energy confinement layer, which contributes to a radiation energy smoothing. In HIF a wobbling he...

  13. Heavy ion physics at LHC with CMS detector

    CERN Document Server

    Kvatadze, R A

    1997-01-01

    The CMS ( Compact Muon Solenoid) is a general purpose detector, optimised for p-p collisions at LHC. However, a very good muon system, fine granularity and excellent energy resolution of electromagnetic and hadron calorimeters and high quality central tracker gives the possibility of using the detector for specific heavy ion studies. Various ways of searching for the phase transition from hadronic matter to the plasma of deconfined quarks and gluons ( QGP) in heavy ion collisions with CMS detector have been investigated: Production of ( bb) and ( cc) resonant states through their muon decay channel to study the colour-screening effect. The dimuon mass spectra and rates of heavy quark bound state production for two weeks of running time are presented. Expected statistics will be sufficient to perfom the Upsilon family suppression study. Detection of J/Psi is mostly concentrated in the forwa rd region. Z production and its subsequent mu+mu- decay can be detected with high statistics and very low background ( 4%...

  14. Hydrodynamics and freeze out problems in energetic heavy ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yun

    2010-09-15

    The work is describing the development from QGP to the final stage (Freeze out) in energetic heavy ion reactions, which is particularly important because this model, based on matter properties we are interested in, describes the observables and can be compared to the experimental results. My doctoral work is mainly on theoretical models, which generated a full list of experimentally observable particles, and then evaluated the produced set of particles, comparable to those in experiments. Thus we produced the same collective observables that are measured in experiments. I concentrated on calculating the flow variables and presented a solution of the continuity equations, which provided a generalized description on matching heavy ion collision stages in a theoretical and simplified way. We also connected our hydrodynamic model with the PACIAE model, aiming for examining the flow properties. This work included the generation of parton distributions for the PACIAE model. The development of hybrid models is now in rapid progress internationally as these models are the most adequate to describe the experimental data in all details. The simple analytic treatment of the hydro and molecular dynamical stages of the model presents an important advantage and increased accuracy in the model construction. (Author)

  15. Energy loss measurements of {sup 63}Cu, {sup 28}Si and {sup 27}Al heavy ions crossing thin Polyvinylchloride (PVC) foil

    Energy Technology Data Exchange (ETDEWEB)

    Dib, A.; Ammi, H. [Centre de Recherche Nucléaire d’Alger, 2 Bd. Frantz Fanon, B.P. 399, Alger-Gare, Algiers (Algeria); Guesmia, A., E-mail: guesmia@tlabs.ac.za [Departement de physique, Faculté des Sciences, Université Saad Dahlab, B. P. 270, Route de Soumaa, Blida (Algeria); Departement de physique, Faculté des Sciences, Université M’hamed Bougara, Boumerdes (Algeria); iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129 (South Africa); Msimanga, M. [Department of Physics, Arcadia Campus, Tshwane University of Technology, P. Bag X680, Pretoria (South Africa); Mammeri, S. [Centre de Recherche Nucléaire d’Alger, 2 Bd. Frantz Fanon, B.P. 399, Alger-Gare, Algiers (Algeria); Hedibel, M. [Departement de physique, Faculté des Sciences, Université M’hamed Bougara, Boumerdes (Algeria); Guedioura, B. [Centre de Recherche Nucléaire de Draria, B.P. 43, Sebala-Draria, Algiers (Algeria); Pineda-Vargas, C.A. [iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129 (South Africa); Faculty of Health and Wellness Sciences, CPUT, P.O. Box 1906, Bellville 7535 (South Africa)

    2015-11-15

    Experimental stopping data of, {sup 63}Cu, {sup 28}Si and {sup 27}Al heavy ions in thin Polyvinylchloride (H{sub 3}C{sub 2}Cl{sub 1}) foil have been obtained over the 0.045–0.50 MeV/nucleon energy range. The measured energy losses were carried out by Heavy Ion Elastic Recoil Detection Analysis (HI-ERDA) technique coupled with time of flight (ToF) spectrometer. A continuous stopping power data obtained in this work are well fitted by our proposed semi-empirical formula and the results are compared to those calculated by LSS formula or generated by SRIM-2013 and MSTAR predictions. Calculations using our formula agree well with the obtained experimental stopping powers, while the LSS formula underestimates the experimental data in the whole investigated energy range. In this work a simple expression for electronic stopping power of heavy ions at low energy in solid targets is introduced. This formula is based on the Firsov and Lindhard–Sharff stopping power models with a small modification made to the original expression, by incorporating the effective charge of moving ions concept and with exponential fit function.

  16. Can van Hove singularities be observed in relativistic heavy-ion ...

    Indian Academy of Sciences (India)

    Keywords. Perturbative quantum chromodynamics; hard thermal loop; gluon condensate; quark–gluon plasma; dispersion relation; collective modes; van Hove singularity; relativistic heavy-ion collisions.

  17. Defect production and annihilation in metals through electronic excitation by energetic heavy ion bombardment

    Energy Technology Data Exchange (ETDEWEB)

    Iwase, Akihiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    Defect production, radiation annealing and defect recovery are studied in Ni and Cu irradiated with low-energy ({approx}1-MeV) and high-energy ({approx}100-MeV) ions. Irradiation of Ni with {approx}100-MeV ions causes an anomalous reduction, or even a complete disappearance of the stage-I recovery. This result shows that the energy transferred from excited electrons to lattice atoms through the electron-lattice interaction contributes to the annihilation of the stage-I interstitials. This effect is also observed in Ni as a large radiation annealing during 100-MeV heavy ion irradiation. On the other hand, in Cu thin foils, we find the defect production process strongly associated with electron excitation, where the defect production cross section is nearly proportional to S{sub e}{sup 2}. (author)

  18. A study of defect cluster formation in vanadium by heavy ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sekimura, Naoto; Shirao, Yasuyuki; Morishita, Kazunori [Tokyo Univ. (Japan)

    1996-10-01

    Formation of defect clusters in thin foils of vanadium was investigated by heavy ion irradiation. In the very thin region of the specimens less than 20 nm, vacancy clusters were formed under gold ion irradiation, while very few clusters were detected in the specimens irradiated with 200 and 400 keV self-ions up to 1 x 10{sup 16} ions/m{sup 2}. The density of vacancy clusters were found to be strongly dependent on ion energy. Only above the critical value of kinetic energy transfer density in vanadium, vacancy clusters are considered to be formed in the cascade damage from which interstitials can escape to the specimen surface in the very thin region. (author)

  19. Radiochemical study of the kinematics of multi-nucleon transfer reactions in 48Ca + 248Cm collisions 10% above the Coulomb barrier

    Science.gov (United States)

    Götz, M.; Götz, S.; Kratz, J. V.; Düllmann, Ch. E.; Mokry, Ch.; Runke, J.; Thörle-Pospiech, P.; Wiehl, N.; Schädel, M.; Ballof, J.; Dorrer, H.; Grund, J.; Huber, D.; Jäger, E.; Keller, O.; Krier, J.; Khuyagbaatar, J.; Lens, L.; Lommel, B.; Mendel, M.; Moody, K. J.; Scharrer, P.; Schausten, B.; Shaughnessy, D.; Schmitt, M.; Steiner, J.; Trautmann, N.; Yakushev, A.; Yakusheva, V.

    2017-05-01

    The kinematics of multi-nucleon transfer reactions in 48Ca + 248Cm collisions at 262 MeV (center of target) was investigated by using a stacked-foil technique and radiochemical separations of trans-curium elements. Trans-curium isotopes were identified by α-particle spectroscopy. For Fm isotopes, by comparing the centroids of the measured post-neutron emission isotope distributions with the most probable primary mass number predicted by Volkov's generalized Qgg systematics, the missing mass (number of evaporated neutrons) is estimated. The latter is compared with that deduced from the measured centroid of the laboratory angular distribution peaked closely to the grazing angle and the centroid of the range distribution, being used to determine the average total kinetic energy loss (TKEL) and the average excitation energy. The latter agrees within the uncertainties with the missing mass so that a consistent picture of the reaction mechanism emerges. For products closer to the target Z, e.g., Cf and Bk, the distributions of kinetic energies are much broader than for Fm, reflecting the fact that in the former, values of TKEL reach from quasi-elastic scattering all the way to deep inelastic scattering. The measured laboratory angular distribution and the average laboratory kinetic energy of the Fm isotopes, being the prototypes for multi-nucleon transfer products, are benchmark values for the design of electromagnetic separators to be constructed for the separation and detection of unknown neutron-rich transactinides produced in this nuclear reaction type.

  20. Contribution of boundness and motion of nucleons to the EMC effect

    OpenAIRE

    Birbrair, B. L.; Ryskin, M.G; Ryazanov, V. I.

    2004-01-01

    The kinematical corrections to the structure function of nucleon in nucleus due to the boundness and motion of nucleons arise from the excitation of the doorway states for one-nucleon transfer reactions in the deep inelastic scattering on nuclei.

  1. Simulations of an Accelerator-based Shielding Shielding Experiment Using theParticle and Heavy-Ion Transport code System PHITS

    Science.gov (United States)

    Sato, T.; Sihver, L.; Iwase, H.; Nakashima, H.; Niita, K.

    In order to estimate the biological effects of HZE particles, an accurate knowledge of the physics of interaction of HZE particles is necessary. Since the heavy ion transport problem is a complex one, there is a need for both experimental and theoretical studies to develop accurate transport models. RIST and JAERI (Japan), GSI (Germany) and Chalmers (Sweden) are therefore currently developing and bench marking the General-Purpose Particle and Heavy-Ion Transport code System (PHITS), which is based on the NMTC and MCNP for nucleon/meson and neutron transport respectively, and the JAM hadron cascade model. PHITS uses JAERI Quantum Molecular Dynamics (JQMD) and the GEM (Generalized Evaporation Model) for calculations of fission and evaporation processes, the SHEN model for calculation of total reaction cross sections, and the SPAR model for dE/dx calculations. The development of PHITS includes better parameterization in the JQMD model used for the nucleus-nucleus reactions, improvement of the models used for calculating total reaction cross sections and dE/dx distributions, and adding routines for calculating elastic scattering of heavy ions, dose and track average LET distributions. As part of an extensive bench marking of PHITS, we have compared energy spectra of secondary neutrons created by reactions of HZE particles with different targets, with thicknesses ranging from simulated and measured spatial, fluence and depth-dose distributions from different high energy heavy ion reactions. In this paper we report simulations of an accelerator-based shielding experiment, in which a beam of 1 GeV/n Fe-ions has passed through slabs of polyethylene, PMMA, Al, and Pb, with thicknesses ranging from 5 to 30 g/cm2 at an acceptance angle of 0°± 3°. The simulated survival fraction of the primary Fe-ions, fragment spectrum for 23 g/cm2, and dose behind the shield per incident Fe-ion on the shield has been compared with measurements.

  2. Nitric oxide-mediated bystander signal transduction induced by heavy-ion microbeam irradiation

    Science.gov (United States)

    Tomita, Masanori; Matsumoto, Hideki; Funayama, Tomoo; Yokota, Yuichiro; Otsuka, Kensuke; Maeda, Munetoshi; Kobayashi, Yasuhiko

    2015-07-01

    In general, a radiation-induced bystander response is known to be a cellular response induced in non-irradiated cells after receiving bystander signaling factors released from directly irradiated cells within a cell population. Bystander responses induced by high-linear energy transfer (LET) heavy ions at low fluence are an important health problem for astronauts in space. Bystander responses are mediated via physical cell-cell contact, such as gap-junction intercellular communication (GJIC) and/or diffusive factors released into the medium in cell culture conditions. Nitric oxide (NO) is a well-known major initiator/mediator of intercellular signaling within culture medium during bystander responses. In this study, we investigated the NO-mediated bystander signal transduction induced by high-LET argon (Ar)-ion microbeam irradiation of normal human fibroblasts. Foci formation by DNA double-strand break repair proteins was induced in non-irradiated cells, which were co-cultured with those irradiated by high-LET Ar-ion microbeams in the same culture plate. Foci formation was suppressed significantly by pretreatment with an NO scavenger. Furthermore, NO-mediated reproductive cell death was also induced in bystander cells. Phosphorylation of NF-κB and Akt were induced during NO-mediated bystander signaling in the irradiated and bystander cells. However, the activation of these proteins depended on the incubation time after irradiation. The accumulation of cyclooxygenase-2 (COX-2), a downstream target of NO and NF-κB, was observed in the bystander cells 6 h after irradiation but not in the directly irradiated cells. Our findings suggest that Akt- and NF-κB-dependent signaling pathways involving COX-2 play important roles in NO-mediated high-LET heavy-ion-induced bystander responses. In addition, COX-2 may be used as a molecular marker of high-LET heavy-ion-induced bystander cells to distinguish them from directly irradiated cells, although this may depend on the time

  3. Investigations of heavy ion tracks in polyethylene naphthalate films

    CERN Document Server

    Starosta, W; Sartowska, B; Buczkowski, M

    1999-01-01

    The heavy ion beam (with fluence 3x10 sup 8 ion/cm sup 2) from a cyclotron has been used for irradiation of thin polyethylene naphthalate (PEN) films. Latent tracks in these polymeric films have been sensitized by UV radiation and then chemically etched in NaOH solution. The etching process parameters have been controlled by the electroconductivity method. After etching, parameters of samples have been examined by SEM and bubble point methods (Coulter[reg] Porometer II instrument). Results have shown good quality of PEN track membranes with pore sizes in the range: 0.1 - 0.5 mu m. The described procedure is known for thin polyethylene terephthalate (PET) films. Taking into consideration that PEN films have got better mechanical, thermal, gas barrier as well as better chemical resistance properties in comparison with PET films, the possibility of application of such membranes is much wider.

  4. High $p_{T}$ physics in the heavy ion era

    CERN Document Server

    Rak, Jan

    2013-01-01

    Aimed at graduate students and researchers in the field of high-energy nuclear physics, this book provides an overview of the basic concepts of large transverse momentum particle physics, with a focus on pQCD phenomena. It examines high $p_{T}$ probes of relativistic heavy-ion collisions and will serve as a handbook for those working on RHIC and LHC data analyses. Starting with an introduction and review of the field, the authors look at basic observables and experimental techniques, concentrating on relativistic particle kinematics, before moving onto a discussion about the origins of high $p_{T}$ physics. The main features of high $p_{T}$ physics are placed within a historical context and the authors adopt an experimental outlook, highlighting the most important discoveries leading up to the foundation of modern QCD theory. Advanced methods are described in detail, making this book especially useful for newcomers to the field.

  5. Crystal-blocking measurements in heavy-ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Gomez del Campo, J.; Fearick, R.W.; Biggerstaff, J.A.; Moak, C.D.; Miller, P.D.; Neskovic, N.; Shapira, D.; Sellschop, J.P.F.

    1983-01-01

    The crystal blocking technique has been employed in the study of /sup 16/O + /sup nat/Ge and /sup 16/O + /sup 12/C (diamond) reactions. Measurements of the projectile-like fragments in the /sup 16/O + Ge reaction gave reaction times as fast as the elastic scattering; however, substantial time effects are seen for the evaporation residues (ER) of the fusion of /sup 16/O + /sup 12/C. Deexcitation times of the ER of 120-MeV /sup 16/O + /sup 12/C, emerging along the (110) axis of a 12-..mu..m diamond crystal were extracted and they ranged from 4 x 10/sup -18/ sec for Mg to 4 x 10/sup -18/ sec for N. These values are consistent with statistical model predictions and demonstrate the sequential decay nature of the deexcitation process in heavy-ion fusion reactions.

  6. Velocity dependence of heavy-ion stopping below the maximum

    Energy Technology Data Exchange (ETDEWEB)

    Sigmund, P., E-mail: sigmund@sdu.dk [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M (Denmark); Schinner, A. [Institut für Experimentalphysik, Johannes Kepler Universität, A-4040 Linz (Austria)

    2015-01-01

    In the slowing-down of heavy ions in materials, the standard description by Lindhard and Scharff assumes the electronic stopping cross section to be proportional to the projectile speed v up to close to a stopping maximum, which is related to the Thomas–Fermi speed v{sub TF}. It is well known that strict proportionality with v is rarely observed, but little is known about the systematics of observed deviations. In this study we try to identify factors that determine positive or negative curvature of stopping cross sections on the basis of experimental data and of binary stopping theory. We estimate the influence of shell structure of the target and of the equilibrium charge of the ion and comment the role of dynamic screening.

  7. Time-of-flight detector for heavy ion backscattering spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, J.A.; Banks, J.C.; Doyle, B.L. [Sandia National Labs., Albuquerque, NM (United States). Ion Solid Interactions and Defect Physics Dept.

    1994-04-01

    This report describes the results of a two-year laboratory directed research and development project to explore advanced concepts in Heavy Ion Backscattering Spectrometry (HIBS), undertaken with the goal of extending the sensitivity of this relatively new technique to levels unattainable by any other existing trace element surface analysis. Improvements in sensitivity are required for the application of HIBS to contamination control in the microelectronics industry. Tools with sensitivity approaching 10{sup 8} atoms/cm{sup 2} are expected to be essential for enabling advanced IC production by the year 2000. During the project the authors developed a new analysis chamber with channeling goniometer and a prototype time-of-flight detector with a demonstrated sensitivity of {approximately} 5 {times} 10{sup 8} atoms/cm{sup 2} for Au on Si and {approximately} 5 {times} 10{sup 10} for Fe, and sufficient mass resolution to separate contributions from Fe and Cu.

  8. Glenn T. Seaborg and heavy ion nuclear science

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-04-01

    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.

  9. Glenn T. Seaborg and heavy ion nuclear science

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-04-01

    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.

  10. Response of the pixel detector Timepix to heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Granja, Carlos, E-mail: carlos.granja@utef.cvut.cz [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Jakubek, Jan [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Koester, Ulli [Institute Laue Langevin, 6 rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); Platkevic, Michal; Pospisil, Stanislav [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic)

    2011-05-15

    The response of the pixel detector Timepix to ions in the 4-110 MeV kinetic energy range and A=3-136 mass range has been studied at the fission-fragment separator Lohengrin of the Institute Laue Langevin in Grenoble. Timepix detects single ions measuring their position, kinetic energy, and time of arrival. Heavy ions with energy above several tens of 10 MeV produce a distortion of the electronic pixel signal response which arises when the energy collected is, under conventional detector settings, of around {approx}1 MeV per pixel. This effect can be suppressed, and the detector energy range extended, by suitable pixel signal baseline and threshold levels, together with optimally low sensor chip bias voltage. Reasonable results are achieved within the range of ion mass and energy studied extending the linearity level of per pixel measured energy up to {approx}2 MeV.

  11. Volume ignition targets for heavy-ion inertial fusion

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Val, J.M.; Eliezer, S.; Piera, M. [Madrid Polytcehnical Univ. (Spain). Inst. of Nuclear Fusion

    1994-12-31

    Inertial confinement fusion (ICF) targets can be imploded by heavy-ion beams (HIBs) in order to obtain a highly compressed fuel microsphere. The hydrodynamic efficiency of the compression can be optimized by tuning the ablation process in order to produce the total evaporation of the pusher material by the end of the implosion. Such pusherless compressions produce very highly compressed targets for relatively short confinement times. However, these times are long enough for a fusion burst to take place, and burnup fractions of 30% and higher can be obtained if the volume ignition requirements are met. Numerical simulations demonstrate that targets of 1-mg DT driven by a few MJ can yield energy gains of over 70. Although direct drive is used in these simulations, the main conclusions about volume ignition are also applicable to indirect drive. (author).

  12. Deposition of molecular probes in heavy ion tracks

    CERN Document Server

    Esser, M

    1999-01-01

    By using polarized fluorescence techniques the physical properties of heavy ion tracks such as the dielectric number, molecular alignment and track radius can be traced by molecular fluorescence probes. Foils of poly(ethylene terephthalate) (PET) were used as a matrix for the ion tracks wherein fluorescence probes such as aminostyryl-derivatives can be incorporated using a suitable solvent, e.g. N,N'-dimethylformamide (DMF) as transport medium. The high sensitivity of fluorescence methods allowed the comparison of the probe properties in ion tracks with the virgin material. From the fluorescence Stokes shift the dielectric constants could be calculated, describing the dielectric surroundings of the molecular probes. The lower dielectric constant in the tracks gives clear evidence that there is no higher accommodation of the highly polar solvent DMF in the tracks compared with the virgin material. Otherwise the dielectric constant in the tracks should be higher than in the virgin material. The orientation of t...

  13. Heavy Ion Collisions at the dawn of the LHC era

    CERN Document Server

    Takahashi, J.

    2013-06-27

    This is a proceeding of the CERN Latin American School of High-Energy physics that took place in the beautiful city of Natal, northern Brazil, in March 2011. In this paper I present a review of the main topics associated with the study of Heavy Ion Collisions, intended for students starting or interested in the field. It is impossible to summarize in a few pages the large amount of information that is available today, after a decade of operations of the RHIC accelerator and the beginning of the LHC operations. Thus, I had to choose some of the results and theories in order to present the main ideas and goals. All results presented here are from publicly available references, but some of the discussions and opinions are my personal view, where I have made that clear in the text.

  14. A new QMD code for heavy-ion collisions

    Science.gov (United States)

    Kim, Kyungil; Kim, Youngman; Lee, Kang Seog

    2017-11-01

    We develop a new quantum molecular dynamics (QMD) type nuclear transport code to simulate heavy-ion collisions for RAON, a new accelerator complex under construction in Korea. At RAON, the rare isotope beams with energies from a few MeV/n to a few hundreds MeV/n will be utilized. QMD is one of the widely used theoretical methods and is useful for both theoretical and experimental purposes. We describe our QMD model with the numerical realization. The validity of the code is tested by comparing our simulation results with experimental data and also results from other transport codes in 197Au+197Au collisions at Elab = 90 - 120 MeV/n. Finally, we present a brief discussion on applicability and outlook of our code.

  15. Beam-beam observations in the Relativistic Heavy Ion Collider

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Y. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Laboratory (BNL), Upton, NY (United States); White, S. [Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2015-06-24

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been operating since 2000. Over the past decade, thanks to the continuously increased bunch intensity and reduced β*s at the interaction points, the maximum peak luminosity in the polarized proton operation has been increased by more than two orders of magnitude. In this article, we first present the beam-beam observations in the previous RHIC polarized proton runs. Then we analyze the mechanisms for the beam loss and emittance growth in the presence of beam-beam interaction. The operational challenges and limitations imposed by beam-beam interaction and their remedies are also presented. In the end, we briefly introduce head-on beam-beam compensation with electron lenses in RHIC.

  16. Heavy ion collision evolution modeling with ECHO-QGP

    Science.gov (United States)

    Rolando, V.; Inghirami, G.; Beraudo, A.; Del Zanna, L.; Becattini, F.; Chandra, V.; De Pace, A.; Nardi, M.

    2014-11-01

    We present a numerical code modeling the evolution of the medium formed in relativistic heavy ion collisions, ECHO-QGP. The code solves relativistic hydrodynamics in (3 + 1)D, with dissipative terms included within the framework of Israel-Stewart theory; it can work both in Minkowskian and in Bjorken coordinates. Initial conditions are provided through an implementation of the Glauber model (both Optical and Monte Carlo), while freezeout and particle generation are based on the Cooper-Frye prescription. The code is validated against several test problems and shows remarkable stability and accuracy with the combination of a conservative (shock-capturing) approach and the high-order methods employed. In particular it beautifully agrees with the semi-analytic solution known as Gubser flow, both in the ideal and in the viscous Israel-Stewart case, up to very large times and without any ad hoc tuning of the algorithm.

  17. Imprint reduction in rotating heavy ions beam energy deposition

    Energy Technology Data Exchange (ETDEWEB)

    Bret, A., E-mail: antoineclaude.bret@uclm.es [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); ETSI Industriales, Universidad Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Piriz, A.R., E-mail: Roberto.Piriz@uclm.es [ETSI Industriales, Universidad Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Tahir, N.A., E-mail: n.tahir@gsi.de [GSI Darmstadt, Plankstrasse 1, 64291 Darmstadt (Germany)

    2014-01-01

    The compression of a cylindrical target by a rotating heavy ions beam is contemplated in certain inertial fusion schemes or in heavy density matter experiments. Because the beam has its proper temporal profile, the energy deposition is asymmetric and leaves an imprint which can have important consequences for the rest of the process. In this paper, the Fourier components of the deposited ion density are computed exactly in terms of the beam temporal profile and its rotation frequency Ω. We show that for any beam profile of duration T, there exist an infinite number of values of ΩT canceling exactly any given harmonic. For the particular case of a parabolic profile, we find possible to cancel exactly the first harmonic and nearly cancel every other odd harmonics. In such case, the imprint amplitude is divided by 4 without any increase of Ω.

  18. Nuclear Fragmentation in Clinical Heavy Ion Beams, Should We Worry?

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, David Christoffer; Toftegaard, Jakob

    particles is formed beyond the Bragg-peak. This tail may deliver unwanted dose to normal tissue, however the magnitude of the tail is directly depending on the inelastic nuclear reaction cross sections. 2. Dosimetry a. Stopping power ratios: Routine dosimetry is performed with air-filled ionization chambers...... the sensitivity on the three fields mentioned above, including: turning off nuclear fragmentation entirely, changing all ineleastic cross sections +/- 20%, changing key parameters in the Fermi-Breakup (FB) model. Results show nuclear effects have their largest impact on the dose distribution. Stopping power......Particle therapy with fast ions is increasingly applied as a treatment option for localized inoperable tumour sites. One of the reasons for the increased complications of understanding heavy ion dosimetry and radiobiology stems from the mixed particle spectrum which occurs due to nuclear...

  19. Stopping of relativistic heavy ions in various media

    Science.gov (United States)

    Waddington, C. J.; Fixsen, D. J.; Crawford, H. J.; Lindstrom, P. J.; Heckman, H. H.

    1986-01-01

    The residual ranges of (900 + or - 3)-MeV/amu gold nuclei accelerated at the Lawrence Berkeley Laboratory Bevalac have been measured in several different media. The energy of the beam of nuclei was measured directly using a new time-of-flight system. The ranges were measured by absorption in linear wedges of polyethylene, carbon, aluminum, copper, tin, and lead and in circular wedges of polystyrene, aluminum, and gold, and by total absorption in nuclear emulsion. The measured ranges were significantly different from those calculated from the best available theoretical estimates of the energy loss of highly charged nuclei. It is concluded that at present energy losses and residual ranges of relativistic heavy ions in an arbitrary medium cannot be predicted with better than an approximately 2 percent accuracy.

  20. Split ring resonator for the Argonne superconducting heavy ion booster

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Scheibelhut, C.H.; Benaroya, R.; Bollinger, L.M.

    1977-01-01

    A split-ring resonator for use in the ANL superconducting heavy-ion linac was constructed and is being tested. The electromagnetic characteristics of the 98-MHz device are the same as the unit described earlier, but the housing is formed of a new material consisting of niobium sheet explosively bonded to copper. The niobium provides the superconducting path and the copper conducts heat to a small area cooled by liquid helium. This arrangement greatly simplified the cryogenic system. Fabrication of the housing was relatively simple, with the result that costs have been reduced substantially. The mechanical stability of the resonator and the performance of the demountable superconducting joints are significantly better than for the earlier unit.

  1. Jets in heavy ion collisions with the ATLAS detector

    CERN Document Server

    Santos, Helena; The ATLAS collaboration

    2018-01-01

    Jets constitute a golden probe to study the quark gluon plasma produced in heavy ion collisions at the LHC. Being produced at the early stages of the collisions, they are expected to be modified as propagating through the hot and dense medium. A signature of the modification is the energy loss lowering the jet yields at a given transverse momentum. A factor of two suppression is observed in central Pb+Pb collisions with respect to pp collisions. Other signatures are the modification of the dijet momentum balance and the modification of fragmentation functions. This talk will present the currently available jet results from ATLAS in Run 2. The high statistical significance of this data sample collected by ATLAS in Run 2 allows precision measurements of these observables in a wide range of transverse momentum, centrality and rapidity intervals.

  2. Jet quenching in heavy-ion collisions with CMS

    CERN Document Server

    Lee, Yen-Jie

    2008-01-01

    The energy loss of fast partons traversing the strongly interacting matter produced in relativistic heavy-ion collisions is one of the most interesting observables to probe the nature of the produced medium. The collisional and radiative energy loss of the partons will modify the fragmentation functions depending on the path length in the medium. In this report, we present a detailed study of complete simulated $\\gamma$-jet events by the CMS detector at LHC in view of the expected modification of jet fragmentation functions in central collisions at $\\sqrt{s_{NN}} = 5.5$ TeV compared to the p+p case. Since the produced prompt photon does not interact strongly with the medium, the initial transverse energy of the fragmentation parton can be related to the photon transverse energy in $\\gamma$-jet events. This enables us to make precision measurements of the modification of the fragmentation function.

  3. Jets in heavy ion collisions with the ATLAS detector

    CERN Document Server

    Santos, Helena; The ATLAS collaboration

    2017-01-01

    Jets constitute a golden probe to study the quark gluon plasma produced in heavy ion collisions at the LHC. Being produced at the early stages of the collisions, they are expected to be modified as propagating through the hot and dense medium. A signature of the modification is the energy loss lowering the jet yields at a given transverse momentum. A factor of two suppression is observed in central Pb+Pb collisions with respect to pp collisions. Other signatures are the modification of the dijet momentum balance and the modification of fragmentation functions. This talk will present the currently available jet results from ATLAS in Run 2. The high statistical significance of this data sample collected by ATLAS in Run 2 allows precision measurements of these observables in a wide range of transverse momentum, centrality and rapidity intervals.

  4. Jets and Vector Bosons in Heavy Ion Collisions

    Directory of Open Access Journals (Sweden)

    de la Cruz Begoña

    2013-11-01

    Full Text Available This paper reviews experimental results on jets and electroweak boson (photon,Wand Z production in heavy-ion collisions, from the CMS and ATLAS detectors, using data collected during 2011 PbPb run and pp data collected at an equivalent energy. By comparing the two collision systems, the energy loss of the partons propagating through the medium produced in PbPb collisions can be studied. Its characterization is done using dijet events and isolated photon-jet pairs. Since the electroweak gauge bosons do not participate in the strong interaction, and are thus unmodified by the nuclear medium, they serve as clean probes of the initial state in the collision.

  5. Heavy-ion physics studies for the Future Circular Collider

    CERN Document Server

    Armesto, Nestor; d'Enterria, David; Masciocchi, Silvia; Roland, Christof; Salgado, Carlos; van Leeuwen, Marco; Wiedemann, Urs

    2014-01-01

    The Future Circular Collider (FCC) design study is aimed at assessing the physics potential and the technical feasibility of a new collider with centre-of-mass energies, in the hadron-hadron collision mode including proton and nucleus beams, more than seven-times larger than the nominal LHC energies. An electron-positron collider in the same tunnel is also considered as an intermediate step, which would provide the electron-hadron option in the long term. First ideas on the physics opportunities with heavy ions at the FCC are presented, covering the physics of Quark-Gluon Plasma, gluon saturation, photon-induced collisions, as well as connections with ultra-high-energy cosmic rays.

  6. Heavy-ion physics studies for the Future Circular Collider

    Energy Technology Data Exchange (ETDEWEB)

    Armesto, N. [Departamento de Física de Partículas and IGFAE, Universidade de Santiago de Compostela, 15706 Santiago de Compostela, Galicia (Spain); Dainese, A., E-mail: andrea.dainese@pd.infn.it [INFN — Sezione di Padova, 35131 Padova (Italy); D' Enterria, D. [Physics Department, CERN, CH-1211 Genéve 23 (Switzerland); Masciocchi, S. [EMMI and GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Roland, C. [Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Salgado, C.A. [Departamento de Física de Partículas and IGFAE, Universidade de Santiago de Compostela, 15706 Santiago de Compostela, Galicia (Spain); Leeuwen, M. van [Nikhef, National Institute for Subatomic Physics and Institute for Subatomic Physics of Utrecht University, Utrecht (Netherlands); Wiedemann, U.A. [Physics Department, CERN, CH-1211 Genéve 23 (Switzerland)

    2014-11-15

    The Future Circular Collider (FCC) design study is aimed at assessing the physics potential and the technical feasibility of a new collider with centre-of-mass energies, in the hadron–hadron collision mode including proton and nucleus beams, more than seven times larger than the nominal LHC energies. An electron–positron collider in the same tunnel is also considered as an intermediate step, which in the long term would allow for electron–hadron collisions. First ideas on the physics opportunities with heavy ions at the FCC are presented, covering the physics of quark–gluon plasma, gluon saturation, photon-induced collisions, as well as connections with the physics of ultra-high-energy cosmic rays.

  7. Modelling early stages of relativistic heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Ruggieri M.

    2016-01-01

    Full Text Available In this study we model early time dynamics of relativistic heavy ion collisions by an initial color-electric field which then decays to a plasma by the Schwinger mechanism. The dynamics of the many particles system produced by the decay is described by relativistic kinetic theory, taking into account the backreaction on the color field by solving self-consistently the kinetic and the field equations. Our main results concern isotropization and thermalization for a 1+1D expanding geometry. In case of small η/s (η/s ≲ 0.3 we find τisotropization ≈ 0.8 fm/c and τthermalization ≈ 1 fm/c in agreement with the common lore of hydrodynamics.

  8. The high current transport experiment for heavy ion inertial fusion

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Baca, D.; Bieniosek, F.M.; Celata, C.M.; Faltens, A.; Henestroza, E.; Kwan, J.W.; Leitner, M.; Seidl, P.A.; Waldron, W.L.; Cohen, R.; Friedman, A.; Grote, D.; Lund, S.M.; Molvik, A.W.; Morse, E.

    2004-05-01

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx} 0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low) nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  9. High current transport experiment for heavy ion inertial fusion

    Directory of Open Access Journals (Sweden)

    L. R. Prost

    2005-02-01

    Full Text Available The High Current Experiment at Lawrence Berkeley National Laboratory is part of the U.S. program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density ∼0.2  μC/m over long pulse durations (4  μs in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo, and electron and gas cloud effects. We present the results for a coasting 1 MeV K^{+} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius for which the transverse phase space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor (≈80% is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  10. Heavy-Ion Radiation Impact on a 4Mb FRAM under Different Test Conditions

    CERN Document Server

    Gupta, V.; Tsiligiannis, G.; Zadeh, A.; Javanainen, A.; Virtanen, A.; Puchner, H.; Saigne, F.; Wrobel, F.; Dilillo, L.

    2015-01-01

    The impact of heavy-ions on commercial Ferroelectric Memories (FRAMs) is analyzed. The influence of different test modes (static and dynamic) on this memory is investigated. Static test results show that the memory is prone to temporary effects occurring in the peripheral circuitry. Dynamic tests results show a high sensitivity of this memory to heavy-ions.

  11. Photon and dilepton production in high-energy heavy-ion collisions

    Indian Academy of Sciences (India)

    2015-05-07

    May 7, 2015 ... The recent results on direct photons and dileptons in high-energy heavy-ion collisions, obtained particularly at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) are reviewed. The results are new not only in terms of the probes, but also in terms of the precision. We shall discuss the ...

  12. The initial stages of heavy-ion collisions in the colour glass ...

    Indian Academy of Sciences (India)

    collision at high energy in the colour glass condensate (CGC) framework. Keywords. Heavy-ion collisions; quantum chromodynamics; colour glass condensate. PACS Nos 12.38.Mh; 11.10.Wx; 12.38.Cy; 11.15.Kc; 12.38.Gc. 1. Introduction. Heavy-ion collisions at ultrarelativistic energies are used to study the properties of ...

  13. Light charged particle emission in heavy-ion reactions – What have ...

    Indian Academy of Sciences (India)

    Light charged particle emission in heavy-ion reactions –. What have we learnt? S KAILAS. Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. Abstract. Light charged particles emitted in heavy-ion induced reactions, their spectra and angu- lar distributions measured over a range of energies, ...

  14. Review on heavy ion radiotherapy facilities and related ion sources (invited)

    NARCIS (Netherlands)

    Kitagawa, A.; Fujita, T.; Muramatsu, M.; Biri, S.; Drentje, A. G.

    Heavy ion radiotherapy awakens worldwide interest recently. The clinical results obtained by the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan have clearly demonstrated the advantages of carbon ion radiotherapy. Presently, there are four

  15. Jet Physics in Heavy Ion Collisions with Compact Muon Solenoid detector at the LHC

    CERN Document Server

    Lokhtin, I P

    2006-01-01

    The status of CMS jet simulations and physics analysis in heavy ion collisions is presented. Jet reconstruction and high transverse momentum particle tracking in the high multiplicity environment of heavy ion collisions at the LHC using the CMS calorimetry and tracking system are described. The Monte Carlo tools used to simulate jet quenching are discussed.

  16. Working group report: Heavy-ion physics and quark-gluon plasma

    Indian Academy of Sciences (India)

    This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported.

  17. Study of transient current induced by heavy-ion microbeams in Si and GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Hirao, Toshio; Nashiyama, Isamu; Kamiya, Tomihiro; Suda, Tamotu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy-ion microbeams were applied to the study of mechanism of single event upset (SEU). Transient current induced in p{sup +}n junction diodes by strike of heavy ion microbeam were measured by using a high-speed digitizing sampling system. (author)

  18. Prospects for parity-nonconservation experiments with highly charged heavy ions

    OpenAIRE

    Maul, Martin; Schäfer, Andreas; Greiner, Walter; Indelicato, Paul

    2006-01-01

    We discuss the prospects for parity-nonconservation experiments with highly charged heavy ions. Energy levels and parity mixing for heavy ions with 2–5 electrons are calculated. We investigate two-photon transitions and the possibility of observing interference effects between weak-matrix elements and Stark matrix elements for periodic electric field configurations.

  19. Prospects for Parity Non-conservation Experiments with Highly Charged Heavy Ions

    OpenAIRE

    Maul, M.; Schäfer, A.; Greiner, W.; Indelicato, P.

    1996-01-01

    We discuss the prospects for parity non-conservation experiments with highly charged heavy ions. Energy levels and parity mixing for heavy ions with two to five electrons are calculated. We investigate two-photon-transitions and the possibility to observe interference effects between weak-matrix elements and Stark matrix elements for periodic electric field configurations.

  20. Direct photon production in heavy-ion reactions at SPS and RHIC

    Indian Academy of Sciences (India)

    The first measurement of direct photons in heavy ion reactions from the WA98 collaboration is discussed and compared to ... Experimentally, high energy direct photon measurement has always been consid- ered a challenge. This is ... charged and neutral pion spectra from different heavy-ion experiments. They estimate a.

  1. Bremsstrahlung from relativistic bare heavy ions: Nuclear and electronic contributions in amorphous and crystalline materials

    DEFF Research Database (Denmark)

    Jensen, Tue Vissing; Sørensen, Allan Hvidkjær

    2013-01-01

    A charged particle emits bremsstrahlung while traversing matter. We calculate the radiation cross section for bare heavy ions penetrating amorphous materials and single crystals at highly relativistic energies. The main component originates in scattering of the virtual photons of screened target...... in a pronounced directional dependence of the energy loss of bare heavy ions at extreme relativistic energies....

  2. Effect of entrance channel parameters on the fusion of two heavy ions

    Indian Academy of Sciences (India)

    the charge state of the energetic heavy ions is important. The selected charge state of the energetic heavy ions might get modified when they traverse through the target foils. The average charge state of the ions emerging from the target ... high-spin isomer was considered to represent the cross-section of the radionuclide.

  3. MEGHNAD – A multi element detector array for heavy ion collision ...

    Indian Academy of Sciences (India)

    gamma, heavy ion and neutron array of detectors (MEGHNAD) to detect and study the properties of a wide variety of ... The gamma detector array consists of four numbers of Clover detectors, a few high efficiency HPGe ... chamber (IC) for measurement of energy and charge of the heavy ions stopping within the active gas ...

  4. Workshop on Heavy Ion Collisions at the LHC: Last Call for Predictions

    CERN Document Server

    Borghini, N; Akkelin, V; Alam, J; Albacete, J L; Andronic, A; Antonov, 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 W; Cleymans, J; Cole, B A; Conesa Del Valle, Z; Csernai, L P; Cunqueiro, L; Dainese, A; Dias de Deus, J; Ding, H T; Djordjevic, M; Drescher, H; Dremin, I M; Dumitru, A; El, A; Engel, R; d'Enterria, D; Eskola, K J; Fái, G; Ferreiro, E G; Fries, R J; Frodermann, E; Fujii, H; Gale, C; Gelis, François; Gonçalves, V P; Greco, V; Greiner, C; Gyulassy, M; Van Hees, H; Heinz, U; Honkanen, H; Horowitz, W A; Iancu, E; Ingelman, G; Jalilian-Marian, J; Jeon, S; Kaidalov, A B; Kämpfer, B; Kang, Z B; Karpenko, Iu 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 A; Lin, Z W; Liu, H; Liu, W; Loizides, C; Lokhtin, I P; Machado, M V T; Malinina, L V; Managadze, A M; Mangano, Michelangelo L; Mannarelli, M; Manuel, C; Martínez, G; Milhano, J G; Mocsy, A; Molnár, D; Nardi, M; Nayak, J K; Niemi, H; Oeschler, H; Ollitrault, J Y; 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 W; Rafelski, J; Rajagopal, K; Ranft, J; Rapp, R; Räasänen, 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; Shoshi, A I; Sinha, B; Sinyukov, Yu M; Snigirev, A M; Srivastava, D K; Stachel, J; Stasto, A; Stöcker, H; Teplov, C Yu; Thews, R L; Torrieri, G; Topor-Pop, V; 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, Urs Achim; Wolschin, G; Xiao, B W; Xu, Z; Yasui, S; Zabrodin, E; Zapp, K; Zhang, B; Zhang, B W; Zhang, H; Zhou, D

    2008-01-01

    This writeup is a compilation of the predictions for the forthcoming Heavy Ion Program at the Large Hadron Collider, as presented at the CERN Theory Institute 'Heavy Ion Collisions at the LHC - Last Call for Predictions', held from May 14th to June 10th 2007.

  5. Direct photon production in heavy-ion reactions at SPS and RHIC

    Indian Academy of Sciences (India)

    A review on experimental results for direct photon production in heavy ion reactions is given. A brief survey of early direct photon limits from SPS experiments is presented. The first measurement of direct photons in heavy ion reactions from the WA98 collaboration is discussed and compared to theoretical calculations.

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

    Science.gov (United States)

    Fries, David P.; Browning, James F.

    1999-01-01

    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.

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

    Science.gov (United States)

    Fries, David P.; Browning, James F.

    1998-01-01

    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.

  8. A large area position-sensitive ionization chamber for heavy-ion-induced reaction studies

    CERN Document Server

    Pant, L M; Dinesh, B V; Thomas, R G; Saxena, A; Sawant, Y S; Choudhury, R K

    2002-01-01

    A large area position-sensitive ionization chamber with a wide dynamic range has been developed to measure the mass, charge and energy of the heavy ions and the fission fragments produced in heavy-ion-induced reactions. The split anode geometry of the detector makes it suitable for both particle identification and energy measurements for heavy ions and fission fragments. The detector has been tested with alpha particles from sup 2 sup 4 sup 1 Am- sup 2 sup 3 sup 9 Pu source, fission fragments from sup 2 sup 5 sup 2 Cf and the heavy-ion beams from the 14UD Mumbai Pelletron accelerator facility. Using this detector, measurements on mass and total kinetic energy distributions in heavy-ion-induced fusion-fission reactions have been carried out for a wide range of excitation energies. Results on deep inelastic collisions and mass-energy correlations on different systems using this detector setup are discussed.

  9. Fragmentation and momentum correlations in heavy-ion collisions

    Indian Academy of Sciences (India)

    Sakshi Gautam and Rajni Kant is very dilute. But, the fragments formed by the MST method will be highly unstable. (especially in central collisions) as there the two nucleons may not be well formed and therefore can be unstable and decay after a while. To filter out such unstable fragments, we impose another cut in terms of ...

  10. Heavy-Ion Radiation Characteristics of DDR2 Synchronous Dynamic Random Access Memory Fabricated in 56 nm Technology

    National Research Council Canada - National Science Library

    Ryu, Kwang-Sun; Park, Mi-Young; Chae, Jang-Soo; Lee, In; Uchihori, Yukio; Kitamura, Hisashi; Takashima, Takeshi

    2012-01-01

    .... To investigate the resistance of the chip to the space radiation environment, we have performed heavy-ion-driven single event experiments using Heavy Ion Medical Accelerator in Chiba medium energy beam line...

  11. Three- and five-nucleon transfers in sup 9 Be( p ,. alpha. ) sup 6 Li reaction at 25 and 30 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, F.; Segato, G.F.; Barbadoro, A.; Corradi, L.; Morando, M.; Pavan, P. (Dipartimento di Fisica, Universita di Padova, Istituto Nazionale di Fisica Nucleare, via Marzolo 8, I-35131, Padova (Italy)); Gabrielli, I. (Dipartimento di Fisica, Universita di Trieste, Istituto Nazionale di Fisica Nucleare, via Valerio 2, I-34127, Trieste (Italy))

    1992-12-01

    Angular distributions of the {sup 9}Be({ital p},{alpha}){sup 6}Li reaction leading to the ground and first two excited states of {sup 6}Li were measured at incident energies of 25.0 and 30.0 MeV. Both the one-step three- and five-nucleon transfers were considered in the theoretical analysis using current shell-model wave functions. We reproduce fairly well with distorted-wave Born approximation theory the experimental energy dependence of the integrated cross sections for the ground and first excited states of {sup 6}Li. A marked disagreement is observed for the second excited state, whose experimental integrated cross section shows a steeper energy dependence than the calculated one.

  12. Antiradiation Vaccine: Technology Development- Radiation Tolerance,Prophylaxis, Prevention And Treatment Of Clinical Presentation After Heavy Ion Irradiation.

    Science.gov (United States)

    Popov, Dmitri; Maliev, Slava; Jones, Jeffrey

    irradiation was generated in heavy ion (Fe56) accelerator - UTI. Heavy Ion linear transfer energy - 2000- 2600 KeV -mkm, 600 MeV -92U. Absorbed Dose - 3820 Rad. Experimental Design: Rabbits from all groups were irradiated by heavy ion accelerator. Group A: control-10 rabbits; Group B: placebo-5 rabbits; Group C: Radioprotectant Cystamine (50 mg-kg)-5 rabbits, 15 minutes before irradiation - 5 rabbits; Group D: Radioprotectant Gammafos (Amifostine 400mg -kg ) - 5 rabbits; Group E: Antiradiation Vaccine: subcutaneus administration or IM - 2 ml of active substance, 14 days before irradiation Results: Group A 100% mortality within two hours after heavy ion irradiation with clinical symptoms of Acute Cerebro- and Cardio-Vascular Radiation syndromes. Group B 100% mortality within 15 hours following irradiation. Group C 100% mortality within 14-15 hours after irradiation. Group D 100% mortality within 15-16 hours after irradiation. In groups A- D registered the development of acute radiation cerebrovascular and cardiovascular syndromes and also extensive burns. of skin produced rapid death. Group E -100% mortality in 280-290 hours (12 days) following heavy ion irradiation with animals exhibiting a combination or individual forms of Acute Cerebrovascular, Cardiovascular, and Gastrointestinal forms and focal skin burns. Discussion Antiradiation vaccine and immune-prophylaxis is an effective method of neutralization of Radiation Toxins. Vaccination before irradiation extended survival time after irradiation with heavy ions from two hours up to 300 hours. Clinical signs, clinical features, symptoms were somewhat attenuated. Degree of clinical forms of Acute Radiation Syndromes were diminished in their clinical manifestation and severity. Groups A-D demonstrated extremely severe level of Cerebrovascular and Cardiovascular forms of Acute Radiation Syndromes and lethality 100% was registered in short time after irradiation. Radiation induced burns in this groups (with Cutaneous sub

  13. Fluctuations in Ultra-Relativistic Heavy Ion Collisions

    Science.gov (United States)

    Mazeliauskas, Aleksas

    Fluctuations are one of the main probes of the physics of the new state of hot and dense nuclear matter called the Quark Gluon Plasma (QGP) which is created in the ultra-relativistic heavy ion collisions. In this dissertation we extend and improve upon the existing descriptions of heavy ion collisions in three different directions: we study the new signatures of initial state fluctuations, the propagation of perturbations in the early stages of the collision, and the effect of thermal fluctuations on the hydrodynamic expansion of the QGP. First, in Chapter 3 we study initial state fluctuations by examining the complete statistical information contained in the two-particle correlation measurements in hydrodynamic simulations of Pb+Pb collisions at the CERN Large Hadron Collider (√sNN = 2.76 TeV). We use Principal Component Analysis (PCA) to decompose the spectrum of harmonic flow, v_n(p_T) for n = 0-5, into dominant components. The leading component is identified with the standard event plane vn(pT), while the subleading component describes additional fluctuations in the two-particle correlation function. We find good geometric predictors for the orientation and the magnitude of the leading and the subleading flows. The subleading v 0, v1, and v3 flow harmonics are shown to be a response to the radial excitation of the corresponding eccentricity epsilonn. In contrast, for v2 the subleading flow in peripheral collisions is dominated by the nonlinear mixing between the leading elliptic flow and radial flow fluctuations. Nonlinear mixing also plays a significant role in generating subleading v4 and v 5 harmonics. The PCA gives a systematic way of studying the full information of the two-particle correlation matrix and identifying the subleading flows, which we show are responsible for factorization breaking in hydrodynamics. Second, in Chapter 4 we study the thermalization and hydrodynamization of fluctuations at the early stages of heavy ion collisions. We use

  14. Modeling and Analysis of Ultrarelativistic Heavy Ion Collisions

    Science.gov (United States)

    McCormack, William; Pratt, Scott

    2014-09-01

    High-energy collisions of heavy ions, such as gold, copper, or uranium serve as an important means of studying quantum chromodynamic matter. When relativistic nuclei collide, a hot, energetic fireball of dissociated partonic matter is created; this super-hadronic matter is believed to be the quark gluon plasma (QGP), which is theorized to have comprised the universe immediately following the big bang. As the fireball expands and cools, it reaches freeze-out temperatures, and quarks hadronize into baryons and mesons. To characterize this super-hadronic matter, one can use balance functions, a means of studying correlations due to local charge conservation. In particular, the simple model used in this research assumed two waves of localized charge-anticharge production, with an abrupt transition from the QGP stage to hadronization. Balance functions were constructed as the sum of these two charge production components, and four parameters were manipulated to match the model's output with experimental data taken from the STAR Collaboration at RHIC. Results show that the chemical composition of the super-hadronic matter are consistent with that of a thermally equilibrated QGP. High-energy collisions of heavy ions, such as gold, copper, or uranium serve as an important means of studying quantum chromodynamic matter. When relativistic nuclei collide, a hot, energetic fireball of dissociated partonic matter is created; this super-hadronic matter is believed to be the quark gluon plasma (QGP), which is theorized to have comprised the universe immediately following the big bang. As the fireball expands and cools, it reaches freeze-out temperatures, and quarks hadronize into baryons and mesons. To characterize this super-hadronic matter, one can use balance functions, a means of studying correlations due to local charge conservation. In particular, the simple model used in this research assumed two waves of localized charge-anticharge production, with an abrupt transition

  15. Structure of High Energy, Heavy Ions in Venus' Upper Ionosphere

    Science.gov (United States)

    Persson, Moa; Futaana, Yoshifumi; Nilsson, Hans; Stenberg Wieser, Gabriella; Hamrin, Maria; Fedorov, Andrei; Barabash, Stas

    2017-04-01

    The solar wind interacts with the atmosphere of Venus, and can reach directly down to the ionosphere. The interaction has previously been studied using the Pioneer Venus mission (PVO) and is now known to cause variations in the density in the ionosphere [Taylor et al., 1980], a transport of ions towards the night side [Knudsen et al., 1980], and an outflow of ions from the atmosphere [Barabash et al., 2007]. Measurements made by PVO showed that the main constituents of Venus ionosphere in the altitude range 150-400 km is the O+ and O2+ ions, where the former dominates from 180 km and higher, and the latter dominates from 180 km down to 150 km [Taylor et al., 1980]. New measurements, made by the Ion Mass Analyzer (IMA) onboard the Venus Express spacecraft, reveal the high-energy (10 eV to 15 keV) plasma characteristics in the ionosphere of Venus. Using the data collected during the low altitude (down to 130 km) pericentre passages during the aerobraking time period, we are able to extract the height profile of the total heavy ion content (O+ and O2+ ions) of Venus ionosphere. The results show two scale heights separated at 200 km; 10 km for 200 km. We interpret the results as two heavy ion components, namely, the O+ ions are dominant for >200 km, while the O2+ is dominant for methods of mass separation, to extract the two ion components of the scale height profiles, (O+ and O2+). First method is to use the moderate mass separation capabilities of the IMA instrument. The individual mass spectra are fitted by two Gaussian curves, representing O+ and O2+, derived from ground calibration information. The second method uses the energy spectrum, which sometimes has two discrete peaks. By assuming the same velocity for different components in the spacecraft reference frame (resulting in different energy for different masses), we can separate the composition. We will discuss the results of the obtained mass separated height profiles.

  16. Review of heavy-ion inertial fusion physics

    Directory of Open Access Journals (Sweden)

    S. Kawata

    2016-03-01

    Full Text Available In this review paper on heavy ion inertial fusion (HIF, the state-of-the-art scientific results are presented and discussed on the HIF physics, including physics of the heavy ion beam (HIB transport in a fusion reactor, the HIBs-ion illumination on a direct-drive fuel target, the fuel target physics, the uniformity of the HIF target implosion, the smoothing mechanisms of the target implosion non-uniformity and the robust target implosion. The HIB has remarkable preferable features to release the fusion energy in inertial fusion: in particle accelerators HIBs are generated with a high driver efficiency of ∼30%–40%, and the HIB ions deposit their energy inside of materials. Therefore, a requirement for the fusion target energy gain is relatively low, that would be ∼50–70 to operate a HIF fusion reactor with the standard energy output of 1 GW of electricity. The HIF reactor operation frequency would be ∼10–15 Hz or so. Several-MJ HIBs illuminate a fusion fuel target, and the fuel target is imploded to about a thousand times of the solid density. Then the DT fuel is ignited and burned. The HIB ion deposition range is defined by the HIB ions stopping length, which would be ∼1 mm or so depending on the material. Therefore, a relatively large density-scale length appears in the fuel target material. One of the critical issues in inertial fusion would be a spherically uniform target compression, which would be degraded by a non-uniform implosion. The implosion non-uniformity would be introduced by the Rayleigh-Taylor (R-T instability, and the large density-gradient-scale length helps to reduce the R-T growth rate. On the other hand, the large scale length of the HIB ions stopping range suggests that the temperature at the energy deposition layer in a HIF target does not reach a very-high temperature: normally about 300 eV or so is realized in the energy absorption region, and that a direct-drive target would be appropriate in HIF. In

  17. An integrated Boltzmann+hydrodynamics approach to heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Hannah

    2009-04-22

    In this thesis the first fully integrated Boltzmann+hydrodynamics approach to relativistic heavy ion reactions has been developed. After a short introduction that motivates the study of heavy ion reactions as the tool to get insights about the QCD phase diagram, the most important theoretical approaches to describe the system are reviewed. The hadron-string transport approach that this work is based on is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) approach. Predictions for the charged particle multiplicities at LHC energies are made. The next step is the development of a new framework to calculate the baryon number density in a transport approach. Time evolutions of the net baryon number and the quark density have been calculated at AGS, SPS and RHIC energies. Studies of phase diagram trajectories using hydrodynamics are performed. The hybrid approach that has been developed as the main part of this thesis is based on the UrQMD transport approach with an intermediate hydrodynamical evolution for the hot and dense stage of the collision. The full (3+1) dimensional ideal relativistic one fluid dynamics evolution is solved using the SHASTA algorithm. Three different equations of state have been used, namely a hadron gas equation of state without a QGP phase transition, a chiral EoS and a bag model EoS including a strong first order phase transition. For the freeze-out transition from hydrodynamics to the cascade calculation two different set-ups are employed. The parameter dependences of the model are investigated and the time evolution of different quantities is explored. The hybrid model calculation is able to reproduce the experimentally measured integrated as well as transverse momentum dependent v{sub 2} values for charged particles. The multiplicity and mean transverse mass excitation function is calculated for pions, protons and kaons in the energy range from E{sub lab}=2-160 A GeV. The HBT correlation of the negatively charged pion source

  18. Interplay of short-range correlations and nuclear symmetry energy in hard-photon production from heavy-ion reactions at Fermi energies

    Science.gov (United States)

    Yong, Gao-Chan; Li, Bao-An

    2017-12-01

    Within an isospin- and momentum-dependent transport model for nuclear reactions at intermediate energies, we investigate the interplay of the nucleon-nucleon short-range correlations (SRCs) and nuclear symmetry energy Esym(ρ ) on hard-photon spectra in collisions of several Ca isotopes on 112Sn and 124Sn targets at a beam energy of 45 MeV/nucleon. It is found that over the whole spectra of hard photons studied, effects of the SRCs overwhelm those owing to the Esym(ρ ) . The energetic photons come mostly from the high-momentum tails (HMTs) of single-nucleon momentum distributions in the target and projectile. Within the neutron-proton dominance model of SRCs based on the consideration that the tensor force acts mostly in the isosinglet and spin-triplet nucleon-nucleon interaction channel, there are equal numbers of neutrons and protons, thus a zero isospin asymmetry in the HMTs. Therefore, experimental measurements of the energetic photons from heavy-ion collisions at Fermi energies have the great potential to help us better understand the nature of SRCs without any appreciable influence by the uncertain Esym(ρ ) . These measurements will be complementary to but also have some advantages over the ongoing and planned experiments using hadronic messengers from reactions induced by high-energy electrons or protons. Because the underlying physics of SRCs and Esym(ρ ) are closely correlated, a better understanding of the SRCs will, in turn, help constrain the nuclear symmetry energy more precisely in a broad density range.

  19. Subthreshold Production of Neutral Pions in Heavy Ion Collisions

    CERN Multimedia

    2002-01-01

    The pion production below the threshold at 290 MeV/u (corresponding to the minimum beam velocity at which pions can be produced in nucleon-nucleon collisions) is sensitive to coherent effects in the momentum distribution of the nucleons in the internuclear collision region. Such collective or coherent effects would manifest themselves in an enhancement of the observed cross section with respect to a prediction on the basis of model momentum distributions, e.g. from the Fermi gas model. \\\\ \\\\ With neutral pions such experiments can be extended to rather low energies and rather small cross sections (in the sub-@mb range) due to the fact that the @p|0's leave the composite nuclear system undisturbed by the Coulomb forces and that their decay $\\gamma$ rays can be detected with high efficiency also at very low pion momentum. In our experiments using |1|2C~ions of 60, 74 and 84~MeV/u and |1|80 of 84~MeV/u we were able to clearly sep from background from different sources. The large efficiency of the annular lead gl...

  20. Two-pion correlations in heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Zajc, W.A.

    1982-08-01

    An application of intensity interferometry to relativistic heavy ion collisions is reported. Specifically, the correlation between two like-charged pions is used to study the reactions Ar+KCl..-->..2..pi../sup +-/+X and Ne+NaF..-->..2..pi../sup -/+X. Source sizes are obtained that are consistent with a simple geometric interpretation. Lifetimes are less well determined but are indicative of a faster pion production process than predicted by Monte Carlo cascade calculations. There appears to be a substantial coherent component of the pion source, although measurement is complicated by the presence of final state interactions. Additionally, the generation of spectra of uncorrelated events is discussed. In particular, the influence of the correlation function on the background spectrum is analyzed, and a prescription for removal of this influence is given. A formulation to describe the statistical errors in the background is also presented. Finally, drawing from the available literature, a self-contained introduction to Bose-Einstein correlations and the Hanbury-Brown - Twiss effect is provided, with an emphasis on points of contact between classical and quantum mechanical descriptions.

  1. The Crystal Collimation System Of The Relativistic Heavy Ion Collider

    CERN Document Server

    Fliller, R P

    2004-01-01

    Crystal Channeling occurs when an ion enters a crystal with a small angle with respect to the crystal planes. The electrostatic interaction between the incoming ion and the lattice causes the ion to follow the crystal planes. By mechanically bending a crystal, it is possible to use a crystal to deflect ions. One novel use of a bent crystal is to use it to channel beam halo particles into a downstream collimator. By deflecting the halo particles into a collimator with a crystal it may be possible to improve the collimation efficiency as compared to a conventional two stage collimation system. A bent crystal was installed in the counterclockwise ring of the Relativistic Heavy Ion Collider (RHIC) prior to the FY2001 run to be used as the first stage of a two stage collimation system. We present a model and simulations to the predict crystal channeling efficiency. The simulations and model predict a channeling efficiency between 59% and 74% depending on the choice of optics. Attempts to reduce backgrounds in RHIC...

  2. An angle-sensitive detection system for scattered heavy ions

    CERN Document Server

    Ganz, R E; Bär, R; Bethge, Klaus; Bokemeyer, H; Folger, H; Samek, M; Salabura, P; Schwalm, D; Stiebing, K E

    1999-01-01

    A compact detection system for heavy ions scattered in collisions at the Coulomb barrier is presented. This system, consisting of four identical, low-pressure Parallel Plate Avalanche Counter (PPAC) modules with two sensitive layers each, was built to operate in an ultra-high-vacuum environment inside the EPoS II solenoid spectrometer at GSI Darmstadt. The detector covers polar angles between 20 deg. and 70 deg. with respect to the beam axis, and about 80% of 2 pi in azimuthal angle. Segmented cathodes and a delay-line read-out allow for a determination of both angles with a precision of delta THETA approx 0.7 deg. in polar and delta PHI approx 1.5 deg. in azimuthal angle, respectively. The system has been proven to be capable of handling instantaneous rates of up to 5x10 sup 5 detected ions per second per module. It neither exhibits the degradation of detection efficiency nor loss in resolution over a 500 h period of a 6 MeV/u sup 2 sup 3 sup 8 U+ sup 1 sup 8 sup 1 Ta measurement at average luminosities of 8...

  3. Irradiation effects of swift heavy ions in matter

    Energy Technology Data Exchange (ETDEWEB)

    Osmani, Orkhan

    2011-12-22

    In the this thesis irradiation effects of swift heavy ions in matter are studied. The focus lies on the projectiles charge exchange and energy loss processes. A commonly used computer code which employs rate equations is the so called ETACHA code. This computer code is capable to also calculate the required input cross-sections. Within this thesis a new model to compute the charge state of swift heavy ions is explored. This model, the so called matrix method, takes the form of a simple algebraic expression, which also requires cross-sections as input. In the present implementation of the matrix method, cross-sections are taken from the ETACHA code, while excitation and deexcitation processes are neglected. Charge fractions for selected ion/target combinations, computed by the ETACHA code and the matrix method are compared. It is shown, that for sufficient large ion energies, both methods agree very well with each other. However, for lower energies pronounced differences are observed. These differences are believed to stem from the fact, that no excited states as well as the decay of theses excited states are included in the present implementation of the matrix method. Both methods are then compared with experimental measurements, where significant deviations are observed for both methods. While the predicted equilibrium charge state by both methods is in good agreement with the experiments, the matrix method predicts a much too large equilibrium thickness compared to both the ETACHA calculation as well as the experiment. Again, these deviations are believed to stem from the fact, that excitation and the decay of excited states are not included in the matrix method. A possible way to include decay processes into the matrix method is presented, while the accuracy of the applied capture cross-sections is tested by comparison with scaling rules. Swift heavy ions penetrating a dielectric are known to induced structural modifications both on the surface and in the bulk

  4. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    Science.gov (United States)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  5. Limiting fragmentation of chemical potentials in heavy ion collisions

    CERN Document Server

    Stiles, L A; Murray, Michael; Stiles, Laura A.

    2006-01-01

    Thermal models have been used to successfully describe the hadron yields from heavy ion collisions at a variety of energies. For root(S)<17 GeV this has usually been done using yields integrated over 4pi but at the higher energies available at RHIC, yields measured at central rapidity have been used. Recent BRAHMS data allows us to test whether thermal models can be generalized to describe the rapidity dependence of particle ratios. We have used the THERMUS package to fit BRAHMS data for the 5% most central Au+Au collisions for several rapidities at root(S) = 62 and 200 GeV. We have found a relationship between the strange and light quark 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.

  6. INFN what next ultra-relativistic heavy-ion collisions

    CERN Document Server

    Dainese, A.; Usai, G.; Antonioli, P.; Arnaldi, R.; Beraudo, A.; Bruna, E.; Bruno, G.E.; Bufalino, S.; Di Nezza, P.; Lombardo, M.P.; Nania, R.; Noferini, F.; Oppedisano, C.; Piano, S.; Prino, F.; Rossi, A.; Agnello, M.; Alberico, W.M.; Alessandro, B.; Alici, A.; Andronico, G.; Antinori, F.; Arcelli, S.; Badala, A.; Barbano, A.M.; Barbera, R.; Barile, F.; Basile, M.; Becattini, F.; Bedda, C.; Bellini, F.; Beole, S.; Bianchi, L.; Bianchin, C.; Bonati, C.; Bossu, F.; Botta, E.; Caffarri, D.; Camerini, P.; Carnesecchi, F.; Casula, E.; Cerello, P.; Cicalo, C.; Cifarelli, M.L.; Cindolo, F.; Colamaria, F.; Colella, D.; Colocci, M.; Corrales Morales, Y.; Cortese, P.; De Caro, A.; De Cataldo, G.; De Falco, A.; De Gruttola, D.; D'Elia, M.; De Marco, N.; De Pasquale, S.; Di Bari, D.; Elia, D.; Fantoni, A.; Feliciello, A.; Ferretti, A.; Festanti, A.; Fionda, F.; Fiorenza, G.; Fragiacomo, E.; Fronze, G.G.; Girard, M. Fusco; Gagliardi, M.; Gallio, M.; Garg, K.; Giubellino, P.; Greco, V.; Grossi, E.; Guerzoni, B.; Hatzifotiadou, D.; Incani, E.; Innocenti, G.M.; Jacazio, N.; Das, S. Kumar; La Rocca, P.; Lea, R.; Leardini, L.; Leoncino, M.; Lunardon, M.; Luparello, G.; Mantovani Sarti, V.; Manzari, V.; Marchisone, M.; Margagliotti, G.V.; Masera, M.; Masoni, A.; Mastroserio, A.; Mazzilli, M.; Mazzoni, M.A.; Meninno, E.; Mesiti, M.; Milano, L.; Moretto, S.; Muccifora, V.; Nappi, E.; Nardi, M.; Nicassio, M.; Pagano, P.; Pappalardo, G.S.; Pastore, C.; Paul, B.; Petta, C.; Pinazza, O.; Plumari, S.; Preghenella, R.; Puccio, M.; Puddu, G.; Ramello, L.; Ratti, C.; Ravasenga, I.; Riggi, F.; Ronchetti, F.; Rucci, A.; Ruggieri, M.; Rui, R.; Sakai, S.; Scapparone, E.; Scardina, F.; Scarlassara, F.; Scioli, G.; Siddhanta, S.; Sitta, M.; Soramel, F.; Suljic, M.; Terrevoli, C.; Trogolo, S.; Trombetta, G.; Turrisi, R.; Vercellin, E.; Vino, G.; Virgili, T.; Volpe, G.; Williams, M.C.S.; Zampolli, C.

    2016-01-01

    This document was prepared by the community that is active in Italy, within INFN (Istituto Nazionale di Fisica Nucleare), in the field of ultra-relativistic heavy-ion collisions. The experimental study of the phase diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP) deconfined state will proceed, in the next 10-15 years, along two directions: the high-energy regime at RHIC and at the LHC, and the low-energy regime at FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the present and future programme of the ALICE experiment, the upgrade of which will open, in the 2020s, a new phase of high-precision characterisation of the QGP properties at the LHC. As a complement of this main activity, there is a growing interest in a possible future experiment at the SPS, which would target the search for the onset of deconfinement using dimuon measurements. On a longer timescale, the community looks with interest at the ongoing studies and discussions on a possible fixed-target p...

  7. Quantifying the sQGP - Heavy Ion Collisions at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Seto, Richard [Univ. of California, Riverside, CA (United States)

    2014-12-01

    This is the closeout for DE-FG02-86ER40271 entitled Quantifying the sQGP - Heavy Ion Collisions at the RHIC. Two major things were accomplished. The first, is the physics planning, design, approval, construction, and commissioning of the MPC-EX. The MPC-EX is an electromagnetic calorimeter covering a rapidity of 3<|eta|<4, which was added to the PHENIX detector. Its primary aim is to measure low-x gluons, in order to understand the suppression seen in a variety of signatures, such as the J/Psi. A candidate to explain this phenomena is the Color Glass Condensate (CGC) A second task was to look at collisions of asymmetric species, in particularly Cu+Au. The signature was the suppression of J/Psi mesons at forward and backward rapidity, where a stronger suppression was seen in the copper going direction. While the blue of the suppression is due to hot nuclear matter effects (e.g. screening) the increase in suppression on the Au side was consistent with cold nuclear matter effects seen in d+Au collisions. A major candidate for the explanation of this phenomena is the aforementioned CGC. Finally the work on sPHENIX, particularly an extension to the forward region, called fsPHENIX is described.

  8. Thermal electromagnetic radiation in heavy-ion collisions

    Science.gov (United States)

    Rapp, R.; van Hees, H.

    2016-08-01

    We review the potential of precise measurements of electromagnetic probes in relativistic heavy-ion collisions for the theoretical understanding of strongly interacting matter. The penetrating nature of photons and dileptons implies that they can carry undistorted information about the hot and dense regions of the fireballs formed in these reactions and thus provide a unique opportunity to measure the electromagnetic spectral function of QCD matter as a function of both invariant mass and momentum. In particular we report on recent progress on how the medium modifications of the (dominant) isovector part of the vector current correlator ( ρ channel) can shed light on the mechanism of chiral symmetry restoration in the hot and/or dense environment. In addition, thermal dilepton radiation enables novel access to a) the fireball lifetime through the dilepton yield in the low invariant-mass window 0.3 GeV ≤ M ≤ 0.7 GeV, and b) the early temperatures of the fireball through the slope of the invariant-mass spectrum in the intermediate-mass region (1.5 GeV < M < 2.5 GeV). The investigation of the pertinent excitation function suggests that the beam energies provided by the NICA and FAIR projects are in a promising range for a potential discovery of the onset of a first-order phase transition, as signaled by a non-monotonous behavior of both low-mass yields and temperature slopes.

  9. Partial correlation analysis method in ultrarelativistic heavy-ion collisions

    Science.gov (United States)

    Olszewski, Adam; Broniowski, Wojciech

    2017-11-01

    We argue that statistical data analysis of two-particle longitudinal correlations in ultrarelativistic heavy-ion collisions may be efficiently carried out with the technique of partial covariance. In this method, the spurious event-by-event fluctuations due to imprecise centrality determination are eliminated via projecting out the component of the covariance influenced by the centrality fluctuations. We bring up the relationship of the partial covariance to the conditional covariance. Importantly, in the superposition approach, where hadrons are produced independently from a collection of sources, the framework allows us to impose centrality constraints on the number of sources rather than hadrons, that way unfolding of the trivial fluctuations from statistical hadronization and focusing better on the initial-state physics. We show, using simulated data from hydrodynamics followed with statistical hadronization, that the technique is practical and very simple to use, giving insight into the correlations generated in the initial stage. We also discuss the issues related to separation of the short- and long-range components of the correlation functions and show that in our example the short-range component from the resonance decays is largely reduced by considering pions of the same sign. We demonstrate the method explicitly on the cases where centrality is determined with a single central control bin or with two peripheral control bins.

  10. Review of Recent Results in Heavy Ion Fluid Dynamics

    Directory of Open Access Journals (Sweden)

    Csernai Laszlo P.

    2014-03-01

    Full Text Available Fluid dynamical phenomena in high energy heavy ion reactions were predicted in the 1970s and still today these are the most dominant and basic observables. With increasing energy and the reach of QGP the low viscosity of the plasma became apparent and this brought a new revolution in the fluid dynamical studies. The high energy and low viscosity made it possible to observe fluctuations up to high multipolarity flow harmonics. This is an obvious, direct proof of the low viscosity of QGP. Many aspects of these fluctuations are under intensive study today. The low viscosity opened ways to observe special fluid dynamical turbulent phenomena. These may arise from random fluctuations, as well as from the global symmetries of peripheral collisions. At LHC energies the angular momentum of the participant matter can reach 106ħ, which leads to rotation and turbulent instabilities, like the Kelvin-Helmholtz instability. Low viscosity ensures that these remain observable at the final freeze-out stages of the collision. Thus new investigations in addition to the standard flow analysis methods became possible. Femtoscopy may also detect rotation and turbulence. Due to the high local thermal vorticity, particle polarization and orbital rotation may reach thermal and mechanical equilibrium. This leads to baryon polarization which, in given directions may be detectable.

  11. Real causes of apparent abnormal results in heavy ion reactions

    Directory of Open Access Journals (Sweden)

    Mandaglio G.

    2015-01-01

    Full Text Available We study the effect of the static characteristics of nuclei and dynamics of the nucleus-nucleus interaction in the capture stage of reaction, in the competition between quasifission and complete fusion processes, as well as the angular momentum dependence of the competition between fission and evaporation processes along the de-excitation cascade of the compound nucleus. The results calculated for the mass-asymmetric and less mass-asymmetric reactions in the entrance channel are analyzed in order to investigate the role of the dynamical effects on the yields of the evaporation residue nuclei. We also discuss about uncertainties at the extraction of such relevant physical quantities as Γn/Γtot ratio or also excitation functions from the experimental results due to the not always realistic assumptions in the treatment and analysis of the detected events. This procedure can lead to large ambiguity when the complete fusion process is strongly hindered or when the fast fission contribution is large. We emphasize that a refined multiparameter model of the reaction dynamics as well as a more detailed and checked data analysis are strongly needed in heavy-ion collisions.

  12. Quarkonia results in heavy-ion collisions from CMS

    CERN Document Server

    AUTHOR|(CDS)2075370

    2015-01-01

    This writeup summarizes CMS results on quarkonia measurements in pp, pPb and PbPb collisions at LHC. CMS has excellent muon detection capabilities which has resulted in a wealth of results on quarkonia (both charmonia as well as bottomonia) measured in dimuon channel. The good mass resolution in dimuon channels allows precise measurement of all three Υ states and their relative yields in pp, pPb as well as PbPb systems, which have ability to quantify the properties of strongly interacting matter. In the charmonia sector, measurements of relative yields of J/ ψ , ψ (2S) are equally useful. In addition excellent vertex capability of CMS enables measurement of B mesons via its decay to J/ ψ which are useful tool to verify energy loss mechanisms of heavy quarks in medium. An overview of these measurements is given. How these measurements compare with other experiments at RHIC and LHC and have improved the understanding of heavy ion collisions has been discussed.

  13. Study of multiple scattering effects in heavy ion RBS

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Z.; O`Connor, D.J. [Newcastle Univ., NSW (Australia). Dept. of Physics

    1996-12-31

    Multiple scattering effect is normally neglected in conventional Rutherford Backscattering (RBS) analysis. The backscattered particle yield normally agrees well with the theory based on the single scattering model. However, when heavy incident ions are used such as in heavy ion Rutherford backscattering (HIRBS), or the incident ion energy is reduced, multiple scattering effect starts to play a role in the analysis. In this paper, the experimental data of 6MeV C ions backscattered from a Au target are presented. In measured time of flight spectrum a small step in front of the Au high energy edge is observed. The high energy edge of the step is about 3.4 ns ahead of the Au signal which corresponds to an energy {approx} 300 keV higher than the 135 degree single scattering energy. This value coincides with the double scattering energy of C ion undergoes two consecutive 67.5 degree scattering. Efforts made to investigate the origin of the high energy step observed lead to an Monte Carlo simulation aimed to reproduce the experimental spectrum on computer. As a large angle scattering event is a rare event, two consecutive large angle scattering is extremely hard to reproduce in a random simulation process. Thus, the simulation has not found a particle scattering into 130-140 deg with an energy higher than the single scattering energy. Obviously faster algorithms and a better physical model are necessary for a successful simulation. 16 refs., 3 figs.

  14. Effects of heavy-ion irradiation on FeSe

    Science.gov (United States)

    Sun, Yue; Park, Akiyoshi; Pyon, Sunseng; Tamegai, Tsuyoshi; Kambara, Tadashi; Ichinose, Ataru

    2017-03-01

    We report the effects of heavy-ion irradiation on FeSe single crystals by irradiating uranium up to a dose-equivalent matching field of Bϕ=16 T. Almost continuous columnar defects along the c axis with a diameter of ˜10 nm are confirmed by high-resolution transmission electron microscopy. Tc is found to be suppressed by introducing columnar defects at a rate of d Tc/d Bϕ˜-0.29 K/T, which is much larger than those observed in iron pnictides. This unexpected large suppression of Tc in FeSe is discussed in relation to the large diameter of the columnar defects as well as its unique band structure with a remarkably small Fermi energy. The critical current density is first dramatically enhanced with irradiation reaching a value over ˜2 ×105A /cm2 (˜5 times larger than that of the pristine sample) at 2 K (self-field) with Bϕ=2 T, then gradually suppressed with increasing Bϕ. The δ l pinning associated with charge-carrier mean-free-path fluctuations and the δ Tc pinning associated with spatial fluctuations of the transition temperature are found to coexist in the pristine FeSe, while the irradiation increases the contribution from δ l pinning and makes it dominant over Bϕ=4 T.

  15. Precision spectroscopy at heavy ion ring accelerator SIS300

    Science.gov (United States)

    Backe, Hartmut

    Unique spectroscopic possibilities open up if a laser beam interacts with relativistic lithium-like ions stored in the heavy ion ring accelerator SIS300 at the future Facility for Antiproton and Ion Research FAIR in Darmstadt, Germany. At a relativistic factor γ=36 the 2P1/2 level can be excited from the 2S1/2 ground state for any element with frequency doubled dye-lasers in collinear geometry. Precise transition energy measurements can be performed if the fluorescence photons, boosted in forward direction into the X-ray region, are energetically analyzed with a single crystal monochromator. The hyperfine structure can be investigated at the 2P1/2-2S1/2 transition for all elements and at the 2P3/2-2S1/2 transition for elements with Z≤50. Isotope shifts and nuclear moments can be measured with unprecedented precision, in principle even for only a few stored radioactive species with known nuclear spin. A superior relative line width in the order of 5·10-7 may be feasible after laser cooling, and even polarized external beams may be prepared by optical pumping.

  16. Heavy Flavor Production in Heavy Ion Collisions at CMS

    CERN Document Server

    Sun, Jian

    2016-01-01

    Studies of Heavy flavor production are of great interest in heavy ion collisions. In the produced medium, the binding potential between a quark and antiquark in quarkonium is screened by surrounding light quarks and antiquarks. Thus, the various quarkonium states are expected to be melt at different temperatures depending on their binding energies, which allows us to characterize the QCD phase transition. In addition, open heavy flavor production are relevant for flavor-dependence of the in-medium parton energy loss. In QCD, gluons are expected to lose more energy compared to quarks when passing through the QGP due to the larger color charge. Compared to light quarks, heavy quarks are expected to lose less radiative energy because gluon radiation is suppressed at angles smaller than the ratio of the quark mass to its energy. This dead cone effect (and its disappearance at high transverse momentum) can be studied using open heavy flavor mesons and heavy flavor tagged jets. With CMS detector, quarkonia, open he...

  17. Hadronic and electromagnetic fragmentation of ultrarelativistic heavy ions at LHC

    Directory of Open Access Journals (Sweden)

    H. H. Braun

    2014-02-01

    Full Text Available Reliable predictions of yields of nuclear fragments produced in electromagnetic dissociation and hadronic fragmentation of ion beams are of great practical importance in analyzing beam losses and interactions with the beam environment at the Large Hadron Collider (LHC at CERN as well as for estimating radiation effects of galactic cosmic rays on the spacecraft crew and electronic equipment. The model for predicting the fragmentation of relativistic heavy ions is briefly described, and then applied to problems of relevance for LHC. The results are based on the fluka code, which includes electromagnetic dissociation physics and dpmjet-iii as hadronic event generator. We consider the interaction of fully stripped lead ions with nuclei in the energy range from about one hundred MeV to ultrarelativistic energies. The yields of fragments close in the mass and charge to initial ions are calculated. The approach under discussion provides a good overall description of Pb fragmentation data at 30 and 158A  GeV as well as recent LHC data for sqrt[s_{NN}]=2.76  TeV Pb-Pb interactions. Good agreement with the calculations in the framework of different models is found. This justifies application of the developed simulation technique both at the LHC injection energy of 177A  GeV and at its collision energies of 1.38, 1.58, and 2.75A  TeV, and gives confidence in the results obtained.

  18. Elastic wave from fast heavy ion irradiation on solids

    CERN Document Server

    Kambara, T; Kanai, Y; Kojima, T M; Nanai, Y; Yoneda, A; Yamazaki, Y

    2002-01-01

    To study the time-dependent mechanical effects of fast heavy ion irradiations, we have irradiated various solids by a short-bunch beam of 95 MeV/u Ar ions and observed elastic waves generated in the bulk. The irradiated targets were square-shaped plates of poly-crystals of metals (Al and Cu), invar alloy, ceramic (Al sub 2 O sub 3), fused silica (SiO sub 2) and single crystals of KC1 and LiF with a thickness of 10 mm. The beam was incident perpendicular to the surface and all ions were stopped in the target. Two piezo-electric ultrasonic sensors were attached to the surface of the target and detected the elastic waves. The elastic waveforms as well as the time structure and intensity of the beam bunch were recorded for each shot of a beam bunch. The sensor placed opposite to the beam spot recorded a clear waveform of the longitudinal wave across the material, except for the invar and fused silica targets. From its propagation time along with the sound velocity and the thickness of the target, the depth of the...

  19. Recent results from the ATLAS heavy ion program

    CERN Document Server

    Havener, Laura Brittany; The ATLAS collaboration

    2018-01-01

    The heavy-ion program in the ATLAS experiment at the LHC originated as an extensive program to probe and characterize the hot, dense matter created in relativistic lead-lead collisions. In recent years, the program has also broadened to a detailed study of collective behavior in smaller systems. In particular, the techniques used to study larger systems are also applied to proton-proton and proton-lead collisions over a wide range of particle multiplicities, to try and understand the early-time dynamics which lead to similar flow-like features in all of the systems. Another recent development is a program studying ultra-peripheral collisions, which provide gamma-gamma and photonuclear processes over a wide range of CM energy, to probe the nuclear wavefunction. This talk presents a subset of the the most recent results from the ATLAS experiment based on Run 1 and Run 2 data, including measurements of collectivity over a wide range of collision systems, potential nPDF modifications — using electroweak bosons,...

  20. Research and development toward heavy ion driven inertial fusion energy

    Directory of Open Access Journals (Sweden)

    Peter A. Seidl

    2013-02-01

    Full Text Available We describe near-term heavy ion fusion (HIF research objectives associated with developing an inertial fusion energy demonstration power plant. The goal of this near-term research is to lay the essential groundwork for an intermediate research experiment (IRE, designed to demonstrate all the key driver beam manipulations at a meaningful scale, and to enable HIF relevant target physics experiments. This is a very large step in size and complexity compared to HIF experiments to date, and if successful, it would justify proceeding to a demonstration fusion power plant. With an emphasis on accelerator research, this paper is focused on the most important near-term research objectives to justify and to reduce the risks associated with the IRE. The chosen time scale for this research is 5–10 years, to answer key questions associated with the HIF accelerator drivers, in turn enabling a key decision on whether to pursue a much more ambitious and focused inertial fusion energy research and development program. This is consistent with the National Academies of Sciences Review of Inertial Fusion Energy Systems Interim Report, which concludes that “it would be premature at the present time to choose a particular driver approach…” and encouraged the continued development of community consensus on critical issues, and to develop “options for a community-based roadmap for the development of inertial fusion as a practical energy source.”

  1. Model of wet chemical etching of swift heavy ions tracks

    Science.gov (United States)

    Gorbunov, S. A.; Malakhov, A. I.; Rymzhanov, R. A.; Volkov, A. E.

    2017-10-01

    A model of wet chemical etching of tracks of swift heavy ions (SHI) decelerated in solids in the electronic stopping regime is presented. This model takes into account both possible etching modes: etching controlled by diffusion of etchant molecules to the etching front, and etching controlled by the rate of a reaction of an etchant with a material. Olivine ((Mg0.88Fe0.12)2SiO4) crystals were chosen as a system for modeling. Two mechanisms of chemical activation of olivine around the SHI trajectory are considered. The first mechanism is activation stimulated by structural transformations in a nanometric track core, while the second one results from neutralization of metallic atoms by generated electrons spreading over micrometric distances. Monte-Carlo simulations (TREKIS code) form the basis for the description of excitations of the electronic subsystem and the lattice of olivine in an SHI track at times up to 100 fs after the projectile passage. Molecular dynamics supplies the initial conditions for modeling of lattice relaxation for longer times. These simulations enable us to estimate the effects of the chemical activation of olivine governed by both mechanisms. The developed model was applied to describe chemical activation and the etching kinetics of tracks of Au 2.1 GeV ions in olivine. The estimated lengthwise etching rate (38 µm · h-1) is in reasonable agreement with that detected in the experiments (24 µm · h-1).

  2. Effects of Heavy Ion Exposure on Nanocrystal Nonvolatile Memory

    Science.gov (United States)

    Oldham, Timothy R.; Suhail, Mohammed; Kuhn, Peter; Prinz, Erwin; Kim, Hak; LaBel, Kenneth A.

    2004-01-01

    We have irradiated engineering samples of Freescale 4M nonvolatile memories with heavy ions. They use Silicon nanocrystals as the storage element, rather than the more common floating gate. The irradiations were performed using the Texas A&M University cyclotron Single Event Effects Test Facility. The chips were tested in the static mode, and in the dynamic read mode, dynamic write (program) mode, and dynamic erase mode. All the errors observed appeared to be due to single, isolated bits, even in the program and erase modes. These errors appeared to be related to the micro-dose mechanism. All the errors corresponded to the loss of electrons from a programmed cell. The underlying physical mechanisms will be discussed in more detail later. There were no errors, which could be attributed to malfunctions of the control circuits. At the highest LET used in the test (85 MeV/mg/sq cm), however, there appeared to be a failure due to gate rupture. Failure analysis is being conducted to confirm this conclusion. There was no unambiguous evidence of latchup under any test conditions. Generally, the results on the nanocrystal technology compare favorably with results on currently available commercial floating gate technology, indicating that the technology is promising for future space applications, both civilian and military.

  3. Thermal electromagnetic radiation in heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, R. [Texas A and M University, Cyclotron Institute and Department of Physics and Astronomy, College Station, TX (United States); Hees, H. van [Goethe-Universitaet Frankfurt, Institut fuer Theoretische Physik, Frankfurt (Germany); Frankfurt Institute of Advanced Studies (FIAS), Frankfurt (Germany)

    2016-08-15

    We review the potential of precise measurements of electromagnetic probes in relativistic heavy-ion collisions for the theoretical understanding of strongly interacting matter. The penetrating nature of photons and dileptons implies that they can carry undistorted information about the hot and dense regions of the fireballs formed in these reactions and thus provide a unique opportunity to measure the electromagnetic spectral function of QCD matter as a function of both invariant mass and momentum. In particular we report on recent progress on how the medium modifications of the (dominant) isovector part of the vector current correlator (ρ channel) can shed light on the mechanism of chiral symmetry restoration in the hot and/or dense environment. In addition, thermal dilepton radiation enables novel access to (a) the fireball lifetime through the dilepton yield in the low invariant-mass window 0.3 GeV ≤ M ≤ 0.7 GeV, and (b) the early temperatures of the fireball through the slope of the invariant-mass spectrum in the intermediate-mass region (1.5 GeV < M < 2.5 GeV). The investigation of the pertinent excitation function suggests that the beam energies provided by the NICA and FAIR projects are in a promising range for a potential discovery of the onset of a first-order phase transition, as signaled by a non-monotonous behavior of both low-mass yields and temperature slopes. (orig.)

  4. Experiments on multi-nucleon transfer reactions with the systems {sup 58,64}Ni+{sup 207}Pb at SHIP

    Energy Technology Data Exchange (ETDEWEB)

    Fernandovich Comas Lijachev, Victor

    2012-07-01

    This work presents experimental results on multi-nucleon transfer reactions in the collision systems {sup 58}Ni+{sup 207}Pb and {sup 64}Ni+{sup 207}Pb which were measured at the velocity filter SHIP at GSI. The reactions were performed at beam energies below and up to 10% above the Coulomb barrier. The work was motivated by theoretical predictions to apply multi-nucleon transfer reactions in heavy systems to synthesize new neutron-rich isotopes in the region of superheavy nuclei with Z>100 and in the region of the closed neutron shell N=126. The expected cross-sections for the production of these nuclei in transfer reactions are small and reach typically nanobarn and below. Therefore, efficient separation techniques have to be applied and the detection system must allow for the identification of single nuclei. A dedicated experimental setup to study such rare transfer products does not exist presently. But already existing facilities which are used for the synthesis of superheavy fusion products meet the requirements for the detection of rare reaction products. In this context, the velocity filter SHIP offers the possibility to separate heavy target-like transfer products from projectiles and projectile-like reaction products before they reach the detection system where the particles are identified by their alpha-decay properties. At SHIP, a cross-section limit of 10 pb can be reached at usual beam intensities. In the present work on collisions of {sup 58,64}Ni+{sup 207}Pb the influence of the projectile neutron number on the cross-sections, isotopic distributions and excitation energies of the transfer products was studied. Especially with the more neutron-rich {sup 64}Ni projectiles a transfer of up to seven protons and eight neutrons to the target nucleus was observed. The largest cross-sections for the most neutron-rich isotopes were reached at the beam energies around the Coulomb barrier. The transfer was accompanied by the full dissipation of the available

  5. Unidirectional stripping extraction from a cyclotron which accelerates light as well as heavy ions

    Directory of Open Access Journals (Sweden)

    Jasna L. Ristić-Djurović

    2003-03-01

    Full Text Available The VINCY Cyclotron (VINča CYclotron is a multipurpose machine intended to accelerate light as well as heavy ions. To extract heavy ions with low energy and light ions an extraction system with stripping foil is used. Heavy ions with high energy will be extracted by means of an electrostatic deflector. The former extraction system will be manufactured and used first. The proposed unidirectional stripping extraction system is the optimal balance between the placement of the extraction line and the required diversity and quality of the extracted beam. The available range of extraction directions is set by geometry limitations.

  6. Isospin splitting of nucleon effective mass and symmetry energy in isotopic nuclear reactions

    Science.gov (United States)

    Guo, Ya-Fei; Chen, Peng-Hui; Niu, Fei; Zhang, Hong-Fei; Jin, Gen-Ming; Feng, Zhao-Qing

    2017-10-01

    Within an isospin and momentum dependent transport model, the dynamics of isospin particles (nucleons and light clusters) in Fermi-energy heavy-ion collisions are investigated for constraining the isospin splitting of nucleon effective mass and the symmetry energy at subsaturation densities. The impacts of the isoscalar and isovector parts of the momentum dependent interaction on the emissions of isospin particles are explored, i.e., the mass splittings of and (). The single and double neutron to proton ratios of free nucleons and light particles are thoroughly investigated in the isotopic nuclear reactions of 112Sn+112Sn and 124Sn+124Sn at incident energies of 50 and 120 MeV/nucleon, respectively. It is found that both the effective mass splitting and symmetry energy impact the kinetic energy spectra of the single ratios, in particular at the high energy tail (larger than 20 MeV). The isospin splitting of nucleon effective mass slightly impacts the double ratio spectra at the energy of 50 MeV/nucleon. A soft symmetry energy with stiffness coefficient of γs=0.5 is constrained from the experimental data with the Fermi-energy heavy-ion collisions. Supported by Major State Basic Research Development Program in China (2014CB845405, 2015CB856903), National Natural Science Foundation of China (11722546, 11675226, 11675066, U1332207) and Youth Innovation Promotion Association of Chinese Academy of Sciences

  7. Recent experimental results in sub- and near-barrier heavy-ion fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Montagnoli, Giovanna [Dipartimento di Fisica e Astronomia, Universita di Padova (Italy); INFN Sezione di Padova (Italy); Stefanini, Alberto M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy)

    2017-08-15

    Recent advances obtained in the field of near and sub-barrier heavy-ion fusion reactions are reviewed. Emphasis is given to the results obtained in the last decade, and focus is mainly on the experimental work performed concerning the influence of transfer channels on fusion cross sections and the hindrance phenomenon far below the barrier. Indeed, early data of sub-barrier fusion taught us that cross sections may strongly depend on the low-energy collective modes of the colliding nuclei, and, possibly, on couplings to transfer channels. The coupled-channels (CC) model has been quite successful in the interpretation of the experimental evidences. Fusion barrier distributions often yield the fingerprint of the relevant coupled channels. Recent results obtained by using radioactive beams are reported. At deep sub-barrier energies, the slope of the excitation function in a semi-logarithmic plot keeps increasing in many cases and standard CC calculations overpredict the cross sections. This was named a hindrance phenomenon, and its physical origin is still a matter of debate. Recent theoretical developments suggest that this effect, at least partially, may be a consequence of the Pauli exclusion principle. The hindrance may have far-reaching consequences in astrophysics where fusion of light systems determines stellar evolution during the carbon and oxygen burning stages, and yields important information for exotic reactions that take place in the inner crust of accreting neutron stars. (orig.)

  8. Heavy-ion beam illumination on a direct-driven pellet in heavy-ion inertial fusion

    Directory of Open Access Journals (Sweden)

    Tetsuo Someya

    2004-04-01

    Full Text Available Key issues in heavy-ion beam (HIB inertial confinement fusion (ICF include an accelerator design for an intense HIB, an efficient HIB transport, a HIB-target interaction, a reactor design, and so on. In this paper, three-dimensional computer simulations are performed for a HIB irradiation onto a direct-driven spherical fuel pellet in HIB-ICF in order to clarify dependence of multi-HIB illumination nonuniformity on parameter values of HIB illumination. For various beam parameters and reactor chamber radii we investigate the energy deposition nonuniformity using 12, 20, 32, 60, 92, and 120-beam irradiation systems. In this study, the effects of HIB temperature, HIB illumination systems, HIB emittance, and pellet temperature on the HIB illumination nonuniformity are also evaluated. In addition, the nonuniformity growth due to a little pellet displacement from a reactor chamber center is investigated. The calculation results demonstrate that we can realize a rather low nonuniform energy deposition, for example, less than 2.0 % even for a 32-beam irradiation system.

  9. Two views on the Bjorken scenario for ultra-relativistic heavy-ion collisions

    CERN Multimedia

    Maire, Antonin

    2011-01-01

    The sketch describes the Bjorken scenario foreseen for the collision of ultra-relativistic heavy-ions, leading to the creation of strongly-interacting hot and dense deconfined matter, the so-called Quark-Gluon Plasma (QGP).

  10. NADPH Oxidase Activation Contributes to Heavy Ion Irradiation–Induced Cell Death

    Directory of Open Access Journals (Sweden)

    Yupei Wang

    2017-03-01

    Full Text Available Increased oxidative stress plays an important role in heavy ion radiation–induced cell death. The mechanism involved in the generation of elevated reactive oxygen species (ROS is not fully illustrated. Here we show that NADPH oxidase activation is closely related to heavy ion radiation–induced cell death via excessive ROS generation. Cell death and cellular ROS can be greatly reduced in irradiated cancer cells with the preincubation of diphenyleneiodium, an inhibitor of NADPH oxidase. Most of the NADPH oxidase (NOX family proteins (NOX1, NOX2, NOX3, NOX4, and NOX5 showed increased expression after heavy ion irradiation. Meanwhile, the cytoplasmic subunit p47phox was translocated to the cell membrane and localized with NOX2 to form reactive NADPH oxidase. Our data suggest for the first time that ROS generation, as mediated by NADPH oxidase activation, could be an important contributor to heavy ion irradiation–induced cell death.

  11. Use of Proton SEE Data as a Proxy for Bounding Heavy-Ion SEE Susceptibility

    Science.gov (United States)

    Ladbury, Raymond L.; Lauenstein, Jean-Marie; Hayes, Kathryn P.

    2015-01-01

    Although heavy-ion single-event effects (SEE) pose serious threats to semiconductor devices in space, many missions face difficulties testing such devices at heavy-ion accelerators. Low-cost missions often find such testing too costly. Even well funded missions face issues testing commercial off the shelf (COTS) due to packaging and integration. Some missions wish to fly COTS systems with little insight into their components. Heavy-ion testing such parts and systems requires access to expensive and hard-to-access ultra-high energy ion accelerators, or significant system modification. To avoid these problems, some have proposed using recoil ions from high-energy protons as a proxy to bound heavy-ion SEE rates.

  12. Symplectic Tracking of Multi-Isotopic Heavy-Ion Beams in SixTrack

    CERN Document Server

    Hermes, Pascal; De Maria, Riccardo

    2016-01-01

    The software SixTrack provides symplectic proton tracking over a large number of turns. The code is used for the tracking of beam halo particles and the simulation of their interaction with the collimators to study the efficiency of the LHC collimation system. Tracking simulations for heavy-ion beams require taking into account the mass to charge ratio of each particle because heavy ions can be subject to fragmentation at their passage through the collimators. In this paper we present the derivation of a Hamiltonian for multi-isotopic heavy-ion beams and symplectic tracking maps derived from it. The resulting tracking maps were implemented in the tracking software SixTrack. With this modification, SixTrack can be used to natively track heavy-ion beams of multiple isotopes through a magnetic accelerator lattice.

  13. What Can We Learn From Proton Recoils about Heavy-Ion SEE Sensitivity?

    Science.gov (United States)

    Ladbury, Raymond L.

    2016-01-01

    The fact that protons cause single-event effects (SEE) in most devices through production of light-ion recoils has led to attempts to bound heavy-ion SEE susceptibility through use of proton data. Although this may be a viable strategy for some devices and technologies, the data must be analyzed carefully and conservatively to avoid over-optimistic estimates of SEE performance. We examine the constraints that proton test data can impose on heavy-ion SEE susceptibility.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-04-29

    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.

  15. Development of heavy-ion irradiation technique for single-event in semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Norio; Akutsu, Takao; Matsuda, Sumio [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Naitoh, Ichiro; Itoh, Hisayoshi; Agematsu, Takashi; Kamiya, Tomihiro; Nashiyama, Isamu

    1997-03-01

    Heavy-ion irradiation technique has been developed for the evaluation of single-event effects on semiconductor devices. For the uniform irradiation of high energy heavy ions to device samples, we have designed and installed a magnetic beam-scanning system in a JAERI cyclotron beam course. It was found that scanned area was approximately 4 x 2 centimeters and that the deviation of ion fluence from the average value was less than 7%. (author)

  16. Magnetic Monopole Mass Bounds from Heavy-Ion Collisions and Neutron Stars.

    Science.gov (United States)

    Gould, Oliver; Rajantie, Arttu

    2017-12-15

    Magnetic monopoles, if they exist, would be produced amply in strong magnetic fields and high temperatures via the thermal Schwinger process. Such circumstances arise in heavy-ion collisions and in neutron stars, both of which imply lower bounds on the mass of possible magnetic monopoles. In showing this, we construct the cross section for pair production of magnetic monopoles in heavy-ion collisions, which indicates that they are particularly promising for experimental searches such as MoEDAL.

  17. Somatic mutation in larvae of the silkworm, Bombyx mori, induced by heavy ion irradiation to diapause eggs

    Energy Technology Data Exchange (ETDEWEB)

    Kotani, Eiji; Furusawa, Toshiharu [Kyoto Inst. of Tech. (Japan). Faculty of Textile Science; Nagaoka, Shunji [Fujita Health Univ., Toyoake, Aichi (Japan). School of Health Sciences] [and others

    2002-12-01

    In order to investigate whether eggs of the black-striped strain (P{sup S}) of the silkworm, Bombyx mori, represent an appropriate model for estimating the biological effect of cosmic radiation, radiosensitivity of the eggs against X-rays and heavy ion particles was examined as ground-based experiments. The exposure of diapause eggs to X-rays or heavy ion particles resulted in somatic mutations appearing as a white spot on the black integument during larval stage. Irradiation of non-diapause eggs with X-rays demonstrated a significant difference in frequency of the mutation between fractionated and single administration doses, but no difference was observed in diapause eggs. Incidence of the mutation as induced by carbon ion beams for 15-day old eggs was higher for eggs that had been kept at 15 deg C than those kept at 25 deg C. Neon beam irradiation of diapause eggs displayed dose- and linear energy transfer (LET)-dependent effects, causing a maximal rate of the mutation at 150 keV/{mu}m. These results confirm that B. mori eggs represent valid models for estimating the biological effects of cosmic radiation. (author)

  18. Beam loss distribution calculation and collimation efficiency simulation of a cooler storage ring in a heavy ion research facility

    Directory of Open Access Journals (Sweden)

    Peng Li

    2014-08-01

    Full Text Available The Heavy Ion Research Facility in Lanzhou is an ion cooler storage ring facility in China’s Institute of Modern Physics. The beams are accumulated, electron cooled, accelerated, and extracted from the main cooler storage ring (CSRm to the experimental ring or different terminals. The heavy ion beams are easily lost at the vacuum chamber along the CSRm when it is used to accumulate intermediate charge state particles. The vacuum pressure bump due to the ion-induced desorption in turn leads to an increase in beam loss rate. In order to avoid the complete beam loss, the collimation system is investigated and planned to be installed in the CSRm. First, the beam loss distribution is simulated considering the particle charge exchanged process. Then the collimation efficiency of the lost particles is calculated and optimized under different position and geometry of the collimators and beam emittance and so on. Furthermore, the beam orbit distortion that is caused by different types of errors in the ring will affect the collimation efficiency. The linearized and inhomogeneous equations of particle motion with these errors are derived and solved by an extended transfer matrix method. Actual magnet alignment errors are adopted to investigate the collimation efficiency of the lost particles in the CSRm. Estimation of the beam loss positions and optimization of the collimation system is completed by a newly developed simulation program.

  19. Alfvénic turbulence in solar wind originating near coronal hole boundaries: heavy-ion effects?

    Directory of Open Access Journals (Sweden)

    B. Bavassano

    2006-03-01

    Full Text Available The mid-latitude phases of the Ulysses mission offer an excellent opportunity to investigate the solar wind originating near the coronal hole boundaries. Here we report on Alfvénic turbulence features, revealing a relevant presence of in-situ generated fluctuations, observed during the wind rarefaction phase that charaterizes the transition from fast to slow wind. Heavy-ion composition and magnetic field measurements indicate a strict time correspondence of the locally generated fluctuations with 1 the crossing of the interface between fast and slow wind and 2 the presence of strongly underwound magnetic field lines (with respect to the Parker spiral. Recent studies suggest that such underwound magnetic configurations correspond to fast wind magnetic lines that, due to footpoint motions at the Sun, have their inner leg transferred to slow wind and are stretched out by the velocity gradient. If this is a valid scenario, the existence of a magnetic connection across the fast-slow wind interface is a condition that, given the different state of the two kinds of wind, may favour the development of processes acting as local sources of turbulence. We suggest that heavy-ion effects could be responsible of the observed turbulence features.

  20. Measurements of Polarization Transfers in Real Compton Scattering by a proton target at JLAB. A new source of information on the 3D shape of the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Fanelli, Cristiano V. [Sapienza Univ. of Rome (Italy)

    2015-03-01

    In this thesis work, results of the analysis of the polarization transfers measured in real Compton scattering (RCS) by the Collaboration E07-002 at the Je fferson Lab Hall-C are presented. The data were collected at large scattering angle (theta_cm = 70deg) and with a polarized incident photon beam at an average energy of 3.8 GeV. Such a kind of experiments allows one to understand more deeply the reaction mechanism, that involves a real photon, by extracting both Compton form factors and Generalized Parton Distributions (GPDs) (also relevant for possibly shedding light on the total angular momentum of the nucleon). The obtained results for the longitudinal and transverse polarization transfers K_LL and K_LT, are of crucial importance, since they confirm unambiguously the disagreement between experimental data and pQCD prediction, as it was found in E99-114 experiment, and favor the Handbag mechanism. The E99-114 and E07-002 results can contribute to attract new interest on the great yield of the Compton scattering by a nucleon target, as demonstrated by the recent approval of an experimental proposal submitted to the Jefferson Lab PAC 42 for a Wide-angle Compton Scattering experiment, at 8 and 10 GeV Photon Energies. The new experiments approved to run with the updated 12 GeV electron beam at JLab, are characterized by much higher luminosities, and a new GEM tracker is under development to tackle the challenging backgrounds. Within this context, we present a new multistep tracking algorithm, based on (i) a Neural Network (NN) designed for a fast and efficient association of the hits measured by the GEM detector which allows the track identification, and (ii) the application of both a Kalman filter and Rauch-Tung-Striebel smoother to further improve the track reconstruction. The full procedure, i.e. NN and filtering, appears very promising, with high performances in terms of both association effciency and reconstruction accuracy, and these preliminary results will

  1. Stopping power measurements of heavy ions (3 {<=} Z{sub 1} {<=} 14) in Mylar foil by time-of-flight spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ammi, H., E-mail: hakim_ammi@yahoo.f [Centre de Recherche Nucleaire d' Alger, 2, Bd. Frantz Fanon, B.P. 399, Alger-Gare (Algeria); Pineda-Vargas, C.A. [iThemba Labs, P.O. Box 722, Somerset West 7129, Cape Town (South Africa); Faculty of Health and Wellness Sciences, CPUT, P.O. Box 1906, Bellville 7535 (South Africa); Mammeri, S. [Centre de Recherche Nucleaire d' Alger, 2, Bd. Frantz Fanon, B.P. 399, Alger-Gare (Algeria); Msimanga, M. [iThemba Labs, P.O. Box 722, Somerset West 7129, Cape Town (South Africa); Ourabah, S.; Dib, A. [Centre de Recherche Nucleaire d' Alger, 2, Bd. Frantz Fanon, B.P. 399, Alger-Gare (Algeria)

    2011-02-01

    Heavy ions elastic recoil detection analysis coupled with time of flight spectrometer (HIERDA{sub T}oF-E) have been used to measure energy loss of charged particles in thin absorber. The stopping power of heavy ions has been determined in Mylar for {sup 28}Si, {sup 27}Al, {sup 24}Mg, {sup 19}F, {sup 16}O, {sup 12}C and {sup 7}Li ions over a continuous range of energies 0.14-0.80 MeV/nucleon. The ions were recoils from the bombardment of different samples (Si, MgO, Al{sub 2}O{sub 3}, LiF and C) with a 27.5 MeV Kr{sup +} beam. The energy loss of the recoil atoms is measured with and without additional foils placed in front of a Surface Barrier Detector (SBD). The energy of individual ions is determined from its ToF data; the exit energy after the stopping foil is measured using the SBD detector. We have compared our stopping values to those predicted by SRIM-2008 computer code, ICRU-73 stopping data tables, MSTAR calculations and to the published data from literature. The results show good agreement with limited existing data but indicate a large deviation among the predicted theoretical values at the low energy side of the stopping maximum peak.

  2. Evaluation of beam wobbling methods for heavy-ion radiotherapy.

    Science.gov (United States)

    Yonai, Shunsuke; Kanematsu, Nobuyuki; Komori, Masataka; Kanai, Tatsuaki; Takei, Yuka; Takahashi, Osamu; Isobe, Yoshiharu; Tashiro, Mutsumi; Koikegami, Hajime; Tomita, Hideki

    2008-03-01

    The National Institute of Radiological Sciences (NIRS) has extensively studied carbon-ion radiotherapy at the Heavy-Ion Medical Accelerator in Chiba (HIMAC) with some positive outcomes, and has established its efficacy. Therefore, efforts to distribute the therapy to the general public should be made, for which it is essential to enable direct application of clinical and technological experiences obtained at NIRS. For widespread use, it is very important to reduce the cost through facility downsizing with minimal acceleration energy to deliver the HIMAC-equivalent clinical beams. For the beam delivery system, the requirement of miniaturization is translated to reduction in length while maintaining the clinically available field size and penetration range for range-modulated uniform broad beams of regular fields that are either circular or square for simplicity. In this paper, we evaluate the various wobbling methods including original improvements, especially for application to the compact facilities through the experimental and computational studies. The single-ring wobbling method used at HIMAC is the best one including a lot of experience at HIMAC but the residual range is a fatal problem in the case of a compact facility. On the other hand, uniform wobbling methods such as the spiral and zigzag wobbling methods are effective and suitable for a compact facility. Furthermore, these methods can be applied for treatment with passive range modulation including respiratory gated irradiation. In theory, the choice between the spiral and zigzag wobbling methods depends on the shape of the required irradiation field. However, we found that it is better to use the zigzag wobbling method with transformation of the wobbling pattern even when a circular uniform irradiation field is required, because it is difficult to maintain the stability of the wobbler magnet due to the rapid change of the wobbler current in the spiral wobbling method. The regulated wobbling method

  3. Remarkable optical-potential systematics for lighter heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Brandan, M.E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, Mexico 01000 Distrito Federal (Mexico); McVoy, K.W. [Physics Department, University of Wisconsin, Madison, Wisconsin 53706 (United States)

    1997-03-01

    Nuclear rainbows, which appear in the elastic scattering angular distributions for certain combinations of lighter heavy ions like {sup 12}C+{sup 12}C and {sup 16}O+{sup 16}O, uniquely determine the major features of the optical potentials for these systems. These features are conveniently summarized by the central depth of the real part of the potential, V(r=0){approximately}100{minus}300 MeV, and by the ratio of imaginary to real parts of the potential, W(r)/V(r), found to be {lt}1 for both small and large r (internal and far-tail transparency), but {approx}1 in the surface region. The resulting maximum in W/V, which is found over the entire energy range 6 MeV {approx_lt}E{sub L}/A{approx_lt}100 MeV, appears to correlate with the peripheral reactions that occur in this energy range. At higher energies the data available indicate that the far-surface region is no longer transparent. Rather, W{approx}V there, suggesting the dominance of nuclear knockout reactions in the far tail. The knockout mode of inelasticity is the one described by the double-Glauber approximation, and W(r){approx}V(r) agrees with the Glauber prediction in the high-energy range. This suggests that the double-Glauber prediction begins to be accurate in the low-density tail of the A{sub 1}+A{sub 2} interaction around E{sub L}/A{approx}100 MeV and that its failure for the higher-density interior may provide a means of investigating the density dependence of Pauli blocking on NN scattering in the nuclear medium. By way of contrast, systems like {sup 20}Ne+{sup 12}C and {sup 14}N+{sup 12}C, which do not exhibit rainbows, have distinctly more absorptive potentials and do not follow the above systematics. This suggests that the imaginary part of the optical potential reflects the shell structure of the target and/or projectile in important ways, and so will not be easy to calculate from an infinite-matter many-body approach. {copyright} {ital 1996} {ital The American Physical Society}

  4. Determination of the excitation energy and angular momentum of the quasi-projectiles produced in the heavy ion collisions Xe + Sn; Determination de l'energie d'excitation et du moment angulaire des quasi-projectiles produits dans les collisions d'ions lourds Xe + Sn

    Energy Technology Data Exchange (ETDEWEB)

    Genouin-Duhamel, Emmanuel [Lab. de Physique Corpusculaire, Caen Univ., 14 Caen (France)

    1999-04-08

    This work is a contribution to the study of properties of hot nuclei formed in heavy ion collisions at intermediate energies. The experiment has been performed with the INDRA multidetector. It is shown that most of the reaction cross section is associated with binary dissipative collisions, accompanied by the production of particles from a region between the two reaction partners. This study is focussed on excitation energy and angular momentum of projectile-like fragment (PLF) in {sup 129}Xe + {sup nat}Sn reactions from 25 to 50 MeV per nucleon. Several methods are used to characterize hot nuclei (velocity, charge, mass and excitation energy). All these methods are compared between them and indicate that high energies are deposited in the nuclei during collision (it may exceed the nucleus binding energy). The angular momentum transferred into intrinsic spin to PLF in the peripheral collisions has been deduced from angular distributions and kinetic energies of the emitted light charged particles (atomic number smaller ar equal to 2). Both methods agree qualitatively. The spin values decrease with the violence of the collision. These values correspond to values averaged over the whole deexcitation chain of nuclei. The predictions of transport models reproduce qualitatively the most peripheral collisions and suggest that high spins are transferred to PLF (from 30 to 50 {Dirac_h}). Larger angular momentum values are observed at the lowest incident energy. The time hierarchy in the evaporation process and the role of mid-rapidity emission are also discussed.

  5. Electroweak bosons in heavy ion collisions in CMS

    Energy Technology Data Exchange (ETDEWEB)

    Zsigmond, Anna Julia

    2014-06-15

    The Compact Muon Solenoid (CMS) is fully equipped to measure leptonic decays of electroweak probes in the high multiplicity environment of nucleus–nucleus collisions. The inclusive and differential Z boson yields in the muon and electron decay channels are presented, together with measurements of the yield of W bosons decaying into a muon and an (anti)neutrino as a function of centrality, and the W charge asymmetry as a function of rapidity. The results confirm the binary scaling hypothesis, and show that possible modifications due to nuclear PDFs with respect to pp collisions, scaled by the number of elementary nucleon–nucleon collisions, are within the statistical and systematic uncertainties of the current measurements.

  6. A large-scale mutant panel in wheat developed using heavy-ion beam mutagenesis and its application to genetic research

    Energy Technology Data Exchange (ETDEWEB)

    Murai, Koji, E-mail: murai@fpu.ac.jp [Department of Bioscience, Fukui Prefectural University, 4-1-1 Matsuoka-Kenjojima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195 (Japan); Nishiura, Aiko [Department of Bioscience, Fukui Prefectural University, 4-1-1 Matsuoka-Kenjojima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195 (Japan); Kazama, Yusuke [RIKEN, Innovation Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Abe, Tomoko [RIKEN, Innovation Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); RIKEN, Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2013-11-01

    Mutation analysis is a powerful tool for studying gene function. Heavy-ion beam mutagenesis is a comparatively new approach to inducing mutations in plants and is particularly efficient because of its high linear energy transfer (LET). High LET radiation induces a higher rate of DNA double-strand breaks than other mutagenic methods. Over the last 12 years, we have constructed a large-scale mutant panel in diploid einkorn wheat (Triticum monococcum) using heavy-ion beam mutagenesis. Einkorn wheat seeds were exposed to a heavy-ion beam and then sown in the field. Selfed seeds from each spike of M{sub 1} plants were used to generate M{sub 2} lines. Every year, we obtained approximately 1000 M{sub 2} lines and eventually developed a mutant panel with 10,000 M{sub 2} lines in total. This mutant panel is being systematically screened for mutations affecting reproductive growth, and especially for flowering-time mutants. To date, we have identified several flowering-time mutants of great interest: non-flowering mutants (mvp: maintained vegetative phase), late-flowering mutants, and early-flowering mutants. These novel mutations will be of value for investigations of the genetic mechanism of flowering in wheat.

  7. FUTURE SCIENCE AT THE RELATIVISTIC HEAVY ION COLLIDER.

    Energy Technology Data Exchange (ETDEWEB)

    LUDLAM, T.

    2006-12-21

    QCD was developed in the 1970's as a theory of the strong interaction describing the confinement of quarks in hadrons. An early consequence of this picture was the realization that at sufficiently high temperature, or energy density, the confining forces are overcome by color screening effects, resulting in a transition from hadronic matter to a new state--later named the Quark Gluon Plasma--whose bulk dynamical properties are determined by the quark and gluon degrees of freedom, rather than those of confined hadrons. The suggestion that this phase transition in a fundamental theory of nature might occur in the hot, dense nuclear matter created in heavy ion collisions triggered a series of experimental searches during the past two decades at CERN and at BNL, with successively higher-energy nuclear collisions. This has culminated in the present RHIC program. In their first five years of operation, the RHIC experiments have identified a new form of thermalized matter formed in Au+Au 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 ( < 1 fm/c) , has an energy density at least 15 times larger than needed for color deconfinement, has a temperature about 2 times the critical temperature of {approx}170 MeV 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. There are also indications that the new form of matter directly involves quarks. Comparison of measured relative hadron abundances with very successful statistical models indicates that hadrons chemically decouple at a temperature of 160-170 MeV. There is evidence suggesting that this happens very close to the

  8. CORONAL SOURCES, ELEMENTAL FRACTIONATION, AND RELEASE MECHANISMS OF HEAVY ION DROPOUTS IN THE SOLAR WIND

    Energy Technology Data Exchange (ETDEWEB)

    Weberg, Micah J. [PhD Candidate in Space Science, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2134A Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Lepri, Susan T. [Associate Professor, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2429 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Zurbuchen, Thomas H., E-mail: mjweberg@umich.edu, E-mail: slepri@umich.edu, E-mail: thomasz@umich.edu [Professor, Space Science and Aerospace Engineering, Associate Dean for Entrepreneurship Senior Counselor of Entrepreneurship Education, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2431 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States)

    2015-03-10

    The elemental abundances of heavy ions (masses larger than He) in the solar wind provide information about physical processes occurring in the corona. Additionally, the charge state distributions of these heavy ions are sensitive to the temperature profiles of their respective source regions in the corona. Heavy ion dropouts are a relatively new class of solar wind events identified by both elemental and ionic charge state distributions. We have shown that their origins lie in large, closed coronal loops where processes such as gravitational settling dominate and can cause a mass-dependent fractionation pattern. In this study we consider and attempt to answer three fundamental questions concerning heavy ion dropouts: (1) 'where are the source loops located in the large-scale corona?'; (2) 'how does the interplay between coronal processes influence the end elemental abundances?'; and (3) 'what are the most probable release mechanisms'? We begin by analyzing the temporal and spatial variability of heavy ion dropouts and their correlation with heliospheric plasma and magnetic structures. Next we investigate the ordering of the elements inside dropouts with respect to mass, ionic charge state, and first ionization potential. Finally, we discuss these results in the context of the prevailing solar wind theories and the processes they posit that may be responsible for the release of coronal plasma into interplanetary space.

  9. Heavy-ion radiation induced Photosynthesis changes in Oryza sativa L.

    Science.gov (United States)

    Zhang, Meng; Sun, Yeqing; Li, Xishan; Meng, Qingmei

    The abnormal development of rice was observed frequently after the seed was exposed to heavy-ion radiation. The heavy-ion radiation could change the chloroplast structure in mesophyll cell by decreasing chloroplast grana and loosing the thylakoid lamellas. To study the mechanism of heavy-ion radiation induced photosynthesis changes, rice seed was exposed to 0-20 Gy dose of (12) C radiation. By measuring the changes of chlorophyll fluorescence parameters, the content of chlorophyll as well as the expression of CP24 in the leaves of rice at the three-leaf stage, we analyzed the influence mechanism of heavy-ion radiation on photosynthesis in rice. The results indicated that chlorophyll fluorescence parameter Fv/Fm and content of chlorophyll (including chlorophyll a, chlorophyll b and total chlorophyll) changed significantly in different doses. Both the relative expression of CP24 and its encoding gene lhcb6 altered after exposed to different dose of radiation. By using Pearson correlation analysis, we found that the 1 Gy was the bound of low-dose radiation. The possible molecular mechanisms and biological consequences of the observed changes are discussed. Key Words: Heavy-ion Radiation; Rice; Photosynthesis; Fv/Fm; CP24.

  10. Collective effects in light–heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Schenke, Björn; Venugopalan, Raju

    2014-11-15

    We present results for the azimuthal anisotropy of charged hadron distributions in A+A, p+A, d+A, and {sup 3}He+A collisions within the IP-Glasma+MUSIC model. Obtained anisotropies are due to the fluid dynamic response of the system to the fluctuating initial geometry of the interaction region. While the elliptic and triangular anisotropies in peripheral Pb+Pb collisions at √(s)=2.76 TeV are well described by the model, the same quantities in √(s)=5.02 TeV p+Pb collisions underestimate the experimental data. This disagreement can be due to neglected initial state correlations or the lack of a detailed description of the fluctuating spatial structure of the proton, or both. We further present predictions for azimuthal anisotropies in p+Au, d+Au, and {sup 3}He+Au collisions at √(s)=200 GeV. For d+Au and {sup 3}He+Au collisions we expect the detailed substructure of the nucleon to become less important.

  11. Photon - Hadron Correlations in Heavy Ion Collisions from PHENIX

    Science.gov (United States)

    Danley, Tyler; Phenix Collaboration

    2017-09-01

    Direct photon-jet pairs are produced in the initial hard scattering of nucleons in A+A collisions in which a quark-gluon plasma is formed. The photon is not affected by the quark-gluon plasma, while the jet loses energy. This allows the direct photon to be an energy calibrator for the jet which can then be studied through photon-hadron pair correlations. Obtaining direct photons is challenging because of the myriad of background photons. Typically, a statistical subtraction method is used in A+A at RHIC. In addition to a statistical method, we have also developed a direct method to obtain isolated photons in A+A by using an isolation cut like those used in direct photon identification in p+p collisions. The isolation cut provides for a cleaner sample of direct photons, potentially reducing the systematic uncertainties on direct photon-hadron correlations when compared to the statistical subtraction sample but presents its own new challenges in the A+A high multiplicity environment. We present the status of centrality-dependent direct photon-hadron angular correlations and fragmentation functions in A+A collisions as well as recent results from recent high-statistics PHENIX datasets.

  12. Recent highlights from the PHENIX heavy ion program

    Directory of Open Access Journals (Sweden)

    Hill J.C.

    2015-01-01

    Full Text Available It is accepted that a QGP can be formed in relativistic collisions of heavy nuclei (A+A. Recently long-range correlations have been observed in p+A collisions at the LHC in high multiplicity events. PHENIX has carried out a series of studies of d+Au collisions at 200 GeV to see if such correlations persist at lower energies compared to those at the LHC. Results of a study of long-range correlations and flow are presented for d+Au collisions. Data from Au+Au collisions collected during the beam energy scan (BES was used to determine both quark and nucleon number scaling. The HBT method was used to determine radii of the fireball at kinetic freezeout. Implications for the nuclear EOS are discussed. Also results of a search for “dark photons” are presented. Recent PHENIX highlights on heavy flavor, electromagnetic probes, spin and plans for PHENIX upgrades were presented in other talks at this conference.

  13. Boson-Jet Correlations in a Hybrid Strong/Weak Coupling Model for Jet Quenching in Heavy Ion Collisions

    CERN Document Server

    Casalderrey-Solana, Jorge; Milhano, Jose Guilherme; Pablos, Daniel; Rajagopal, Krishna

    2016-01-01

    We confront a hybrid strong/weak coupling model for jet quenching to data from LHC heavy ion collisions. The model combines the perturbative QCD physics at high momentum transfer and the strongly coupled dynamics of non- abelian gauge theories plasmas in a phenomenological way. By performing a full Monte Carlo simulation, and after fitting one single parameter, we successfully describe several jet observables at the LHC, including dijet and photon jet measurements. Within current theoretical and experimental uncertainties, we find that such observables show little sensitivity to the specifics of the microscopic energy loss mechanism. We also present a new observable, the ratio of the fragmentation function of inclusive jets to that of the associated jets in dijet pairs, which can discriminate among different medium models. Finally, we discuss the importance of plasma response to jet passage in jet shapes.

  14. Simulating spin dynamics with spin-dependent cross sections in heavy-ion collisions

    Science.gov (United States)

    Xia, Yin; Xu, Jun; Li, Bao-An; Shen, Wen-Qing

    2017-10-01

    We have incorporated the spin-dependent nucleon-nucleon cross sections into a Boltzmann-Uehling-Uhlenbeck transport model for the first time, using the spin-singlet and spin-triplet nucleon-nucleon elastic scattering cross sections extracted from the phase-shift analyses of nucleon-nucleon scatterings in free space. We found that the spin splitting of the collective flows is not affected by the spin-dependent cross sections, justifying it as a good probe of the in-medium nuclear spin-orbit interaction. With the in-medium nuclear spin-orbit mean-field potential that leads to local spin polarization, we found that the spin-averaged observables, such as elliptic flows of free nucleons and light clusters, becomes smaller with the spin-dependent differential nucleon-nucleon scattering cross sections.

  15. Measurement of quarkonia production in heavy-ion collisions with the ATLAS detector

    CERN Document Server

    Tapia Araya, Sebastian; The ATLAS collaboration

    2017-01-01

    The suppression of heavy quarkonia states in heavy-ion collisions is a phenomenon understood as a consequence of QGP formation in the hot, dense system formed in heavy-ion collisions at the LHC. In addition to hot matter effects in heavy-ion collisions , cold nuclear effects may also affect quarkonia production . Therefore, a full assessment requires detailed studies on the effects present in both A-A and p+A collisions. Based on p+Pb data collected in 2013 and pp and Pb+Pb data collected in 2015 at the LHC, the ATLAS experiment has studied prompt and non-prompt J/psi and psi(2S) productions as well as Upsilon production via the di-muon decay final states. The results are of the various measurements are discussed.

  16. A high energy, heavy ion microprobe for ion beam research on the tandem accelerator at ANSTO

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, D.D.; Siegele, R.; Dytlewski, N.

    1996-04-01

    A comprehensive review is given on the production and use of heavy ion beams with spot sizes of a few {mu}m. The development of a high energy, heavy ion microprobe at ANSTO and its possible applications are discussed. The microprobe is designed to focus a wide range of ion beam types, from light ions such as protons up to ions as heavy as iodine. Details of the ion beam optics, optical calculations and a description of the proposed microbeam design are given. The unique combination of high energy, heavy ions and improved detection systems will provide high sensitivity elemental composition and depth profiling information, allowing surface topography and 3D surface reconstruction to be performed on a broad range of materials. 86 refs., 5 tabs., 15 figs.

  17. Heavy Ion Fusion Accelerator Research (HIFAR) year-end report, October 1, 1987--March 31, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    The basic objective of the Heavy Ion Fusion Accelerator Research (HIFAR) program is to assess the suitability of heavy ion accelerators as igniters for Inertial Confinement Fusion (ICF). A specific accelerator technology, the induction linac, has been studied at Lawrence Berkeley Laboratory and has reached the point at which its viability for ICF applications can be assessed over the next few years. The HIFAR program addresses the generation of high-power, high-brightness beams of heavy ions, the understanding of the scaling laws in this novel physics regime, and the validation of new accelerator strategies, to cut costs. Key elements to be addressed include: beam quality limits set by transverse and longitudinal beam physics; development of induction accelerating modules, and multiple-beam hardware, at affordable costs; acceleration of multiple beams with current amplification -- both new features in a linac -- without significant dilution of the optical quality of beams; and final bunching, transport, and accurate focusing on a small target.

  18. Materials science symposium 'heavy ion science in tandem energy region'

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Akira; Yoshida, Tadashi; Takeuchi, Suehiro (eds.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-11-01

    The facility of the JAERI tandem accelerator and its booster has been contributing to obtain plenty of fruitful results in the fields of nuclear physics, nuclear chemistry, atomic and solid state physics and materials science, taking an advantage of its prominent performances of heavy ion acceleration. The previous meeting held in 1999 also offered an opportunity to scientists from all over the heavy ion science fields, including nuclear physics, solid state physics and cross-field physics to have active discussions. This meeting included oral presentations with a new plan and with a new scope of fields expected from now on, as an occasion for opening the 21st century in heavy ion science. The 50 of the presented papers are indexed individually. (J.P.N.)

  19. Studying Heavy Ion Collisions Using Methods From Cosmic Microwave Background (CMB Analysis

    Directory of Open Access Journals (Sweden)

    Gaardhøje J. J.

    2014-04-01

    Full Text Available We present and discuss a framework for studying the morphology of high-multiplicity events from relativistic heavy ion collisions using methods commonly employed in the analysis of the photons from the Cosmic Microwave Background (CMB. The analysis is based on the decomposition of the distribution of the number density of (charged particles expressed in polar and azimuthal coordinates into a sum of spherical harmonic functions. We present an application of the method exploting relevant symmetries to the study of azimuthal correlations arizing from collective flow among charged particles produced in relativistic heavy ion collisions. We discuss perspectives for event-by- event analyses, which with increasing collision energy will eventually open entirely new dimensions in the study of ultrarelaticistic heavy ion reactions.

  20. Cern academic training programme 2011: Selected Topics in the Physics of Heavy Ion Collisions

    CERN Multimedia

    PH Department

    2011-01-01

    LECTURE SERIES 14, 15 & 16 March 2011 Selected Topics in the Physics of Heavy Ion Collisions 11:00-12:00 - Bldg. 222-R-001 - Filtration Plant In these lectures, I discuss some classes of measurements accessible in heavy ion collisions at the LHC. How can these observables be measured, to what extent can they be calculated, and what do they tell us about the dense mesoscopic system created during the collision? In the first lecture, I shall focus in particular on measurements that constrain the spatio-temporal picture of the collisions and that measure centrality, orientations and extensions. In the subsequent lectures, I then discuss on how classes of measurements allow one to characterize collective phenomena, and to what extent these measurements can constrain the properties of matter produced in heavy ion collisions. Organiser: Maureen Prola-Tessaur/PH-EDU  

  1. Recent progress and future plans of heavy-ion cancer radiotherapy with HIMAC

    Science.gov (United States)

    Noda, K.; Furukawa, T.; Fujimoto, T.; Hara, Y.; Inaniwa, T.; Iwata, Y.; Katagiri, K.; Kanematsu, N.; Mizushima, K.; Mori, S.; Saotome, N.; Saraya, Y.; Sato, S.; Shirai, T.; Takada, M.; Takei, Y.; Tansyo, R.; Yonai, S.

    2017-09-01

    The HIMAC clinical study has been conducted with a carbon-ion beam since June 1994. Since 2006, as a new treatment research project, NIRS has developed both the accelerator and beam-delivery technologies for the sophisticated heavy-ion radiotherapy, which brings a pencil-beam 3D rescanning technology for both the static and moving-tumor treatments. In this technology, the depth-scanning technique was improved to the full-energy depth scanning by realizing a variable-energy operation of the HIMAC synchrotron itself. At present, a heavy-ion rotating gantry has been developed with the superconducting technology and is in a beam-commissioning stage. As a future plan, we just start a study of a multi-ions irradiation for more sophisticated LET-painting and a design study of a superconducting synchrotron for more compact heavy-ion radiotherapy facility.

  2. Measurement of quarkonia production in heavy-ion collisions with the ATLAS detector

    CERN Document Server

    Kremer, Jakub Andrzej; The ATLAS collaboration

    2017-01-01

    The suppression of heavy quarkonia states in heavy-ion collisions is a phenomenon understood as a consequence of QGP formation in the hot, dense system formed in heavy-ion collisions at the LHC. In addition to hot matter effects in heavy-ion collisions, cold nuclear effects may also affect quarkonia production. Therefore, a full assessment requires detailed studies on the effects present in both A-A and p+A collisions. Based on p+Pb data collected in 2013 and pp and Pb+Pb data collected in 2015 at the LHC, the ATLAS experiment has studied prompt and non-prompt J/psi and psi(2S) productions as well as Upsilon production via the di-muon decay final states. The results of the various measurements are discussed

  3. Heavy-ion-induced x-ray satellite emission as a chemical probe

    Energy Technology Data Exchange (ETDEWEB)

    Rosseel, T.M.; Dale, J.M.; Hulett, L.D.; Krause, H.F.; Raman, S.; Vane, C.R.; Young, J.P.

    1983-01-01

    Advances in energy technology often require correspondidng advances in materials fabrication and characterization. Among the new techniques being developed for the improved characterization of materials is an x-ray fluorescence method which uses heavy ions for excitation. High resolution measurements of heavy-ion excited x-ray spectra have revealed a series of prominent satellite lines in addition to the normal emission lines. It has been shown that these satellites display intensity variations indicative of the chemical state or environment of the emitting target atom and the projectile velocity. In order to evaluate heavy-ion induced x-ray satellite emission (HIXSE) as a chemical probe, we have examined a series of sulfur compounds and titanium, vanadium and molybdenum alloys and compounds. Results will be presented which demonstrate the chemical sensitivity of this technique, the range of elements which can be analyzed and the potential for applications to real chemical and materials problems.

  4. Track reconstruction in heavy ion collisions with the CMS silicon tracker

    CERN Document Server

    Roland, C

    2006-01-01

    The Large Hadron Collider at CERN will collide protons at \\sqrtS = 14TeV and lead ions at \\sqrt$\\S_{NN}$. The study of heavy ion collisions is an integral part of the physics program of the Compact Muon Solenoid (CMS). Central heavy ion events at LHC energies are expected to produce a multiplicity of up to 3500 charged particles per unit of rapidity. The CMS detector features a large acceptance and high resolution silicon tracker consisting of pixel and strip detector layers. We describe the algorithms used for pattern recognition in the very high track density environment of heavy ion collisions. Detailed studies using the full detector simulation and reconstruction are presented and achieved reconstruction efficiencies, fake rates and resolutions are discussed.

  5. Coulomb-driven energy boost of heavy ions for laser-plasma acceleration.

    Science.gov (United States)

    Braenzel, J; Andreev, A A; Platonov, K; Klingsporn, M; Ehrentraut, L; Sandner, W; Schnürer, M

    2015-03-27

    An unprecedented increase of kinetic energy of laser accelerated heavy ions is demonstrated. Ultrathin gold foils have been irradiated by an ultrashort laser pulse at a peak intensity of 8×10^{19}  W/  cm^{2}. Highly charged gold ions with kinetic energies up to >200  MeV and a bandwidth limited energy distribution have been reached by using 1.3 J laser energy on target. 1D and 2D particle in cell simulations show how a spatial dependence on the ion's ionization leads to an enhancement of the accelerating electrical field. Our theoretical model considers a spatial distribution of the ionization inside the thin target, leading to a field enhancement for the heavy ions by Coulomb explosion. It is capable of explaining the energy boost of highly charged ions, enabling a higher efficiency for the laser-driven heavy ion acceleration.

  6. Femtoscopic analysis of baryon correlations in ultra-relativistic heavy-ion collisions registered by ALICE

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00361630

    Heavy-ion collisions at ultra-relativistic energies give a unique possibility to create and to analyse the Quark-Gluon Plasma predicted by the theory of Quantum Chromodynamics. The research on the properties of such state of matter is crucial for understanding the features of the strongly interacting system. Experimental results reveal the collective behaviour of matter created in the heavy-ion collisions at ultra-relativistic energies. The existence of this effect can be verified by the measurement of the transverse mass dependence of the source size extracted using different particle species. Such characteristics can be determined using the analysis technique called femtoscopy. This method is based on the correlations of particles with small relative momenta which originate from the effects of Quantum Statistics as well as the strong and Coulomb Final State Interactions. A recent analysis of the particle production at the highest available collision energies of heavy-ion collisions reveals the puzzling res...

  7. Comparison of space-time evolutions of hot, dense matter in $\\sqrt{s_{NN}}$ =17 and 130 GeV relativistic heavy ion collisions based on a hydrodynamical model

    CERN Document Server

    Morita, K; Nonaka, C; Hirano, T; 10.1103/PhysRevC.66.054904

    2002-01-01

    Based on a hydrodynamical model, we compare 130 GeV/nucleon Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) and 17 GeV /nucleon Pb+Pb collisions at the Super Proton Synchrotron (SPS). The model well reproduces the single-particle distributions of both the RHIC and SPS. The numerical solution indicates that a huge amount of collision energy in the RHIC is mainly used to produce a large extent of hot fluid rather than to make a high temperature matter; the longitudinal extent of the hot fluid in the RHIC is much larger than that of the SPS and the initial energy density of the fluid is only 5% higher than the one in the SPS. The solution well describes the HBT radii at the SPS energy but shows some deviations from the ones at the RHIC. (41 refs).

  8. Octopole correction of geometric aberrations for high-current heavy-ion fusion beams

    Energy Technology Data Exchange (ETDEWEB)

    Ho, D.D.M.; Haber, I.; Crandall, K.R.; Brandon, S.T.

    1989-03-17

    The success of heavy-ion fusion depends critically on the ability to focus heavy-ion beams to millimeter-size spots. Third-order geometric aberrations caused by fringe fields of the final focusing quadrupoles can significantly distort the focal spot size calculated by first-order theory. We present a method to calculate the locations and strengths of the octopoles that are needed to correct these aberrations. Calculation indicates that the strengths of the octopoles are substantially less than that of the final focusing quadrupoles. 9 refs., 1 fig.

  9. Measurement Of The Heavy-Ion Collision Event Characteristics With The Atlas Experiment At The Lhc

    Directory of Open Access Journals (Sweden)

    Iwona Grabowska-Bołd

    2015-01-01

    Full Text Available Heavy-ion collisions at extreme energies can reproduce conditionspresent in the early Universe. The new state of very dense and hotmatter of deconfined quarks and gluons, called the Quark GluonPlasma~(QGP, is observed. This state is characterised by very lowviscosity resembling the properties of a perfect fluid. In suchmedium, the density fluctuations can be easily spread. In experimentalpractice, the size of these fluctuations is estimated by measuring theangular correlation of produced particles. The aim of this paper isto present measurements of the azimuthal anisotropy of chargedparticles produced in heavy-ion collisions using the ATLAS detector atthe LHC. Two measurement techniques are presented and compared.

  10. Investigating local parity violation in heavy-ion collisions using Λ helicity

    Science.gov (United States)

    Finch, L. E.; Murray, S. J.

    2017-10-01

    We propose the measurement of net Λ and Λ ¯ helicity, correlated event by event with the magnitude and sign of charge separation along the event's magnetic field direction, as a probe to investigate the chiral magnetic effect (CME) in heavy-ion collisions. With a simple simulation model of heavy-ion events that includes effects of local parity violation, we estimate the experimental correlation signal that could be expected at RHIC given the results of previous measurements that are sensitive to the CME.

  11. Numerical investigation of performance of some designs of heavy ion thermonuclear fusion target

    Energy Technology Data Exchange (ETDEWEB)

    Vatulin, V.V. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.; Voronin, B.L. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.; Zagrafov, V.G. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.; Remizov, G.N. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.; Skidan, G.I. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.; Skrypnik, S.I. [Russian Federal Nucl. Centre, Arzamas (Russian Federation). Inst. of Exp. Phys.

    1996-11-01

    At present one of the main problems to be solved in heavy ion inertial fusion is the development of an operative design for a target compatible with the beam geometries by a driver. This report presents the research results obtained so far on the target parameters with a cylindrical chamber and converters mounted on the lateral surface of the chamber walls. The cited results were obtained by numerical simulation of X-ray generation in heavy ion flux irradiation, X-ray radiation propagation in the hohlraum volume and gas dynamic processes with 2D and 3D mathematical codes developed at VNIIEF. (orig.)

  12. [The heavy ion irradiation influence on the thermodynamic parameters of liquids in human body].

    Science.gov (United States)

    Vlasenko, T S; Bulavin, L A; Sysoev, V M

    2014-01-01

    In this manuscript a theoretical model describing the influence of the heavy ion radiotherapy on the liquid matter in the human body is suggested. Based on the fundamental equations of Bogoliubov chain the effective temperatures in the case of constant particles fluent are found in the context of single component model. An existence of such temperatures allows the use of equilibrium thermodynamics formalism to nonequilibrium stationary state. The obtained results provide the possibility of predicting the liquid matter structural changes in the biological systems in the area influenced by the heavy ion beams.

  13. Heavy ion dynamics and auroral arc formation in the Jovian magnetosphere

    Science.gov (United States)

    Barbosa, D. D.

    1992-01-01

    This paper gives a brief review of some of the current controversial issues surrounding the Jovian aurora. In particular, the manner of its excitation be it that of electron or heavy ion precipitation is examined critically in the context of proposed models for magnetospheric dynamics, particle energization, and auroral energy input. A model for the X-ray aurora based on bremsstrahlung by a primary electron beam and its ionization secondaries is high-lighted and the connection to the outward magnetospheric transport of heavy ion plasma from the satellite Io is made.

  14. Measurement of charge of heavy ions in emulsion using a CCD camera

    CERN Document Server

    Kudzia, D; Dabrowska, A; Deines-Jones, P; Holynski, R; Olszewski, A; Nilsen, B S; Sen-Gupta, K; Szarska, M; Trzupek, A; Waddington, C J; Wefel, J P; Wilczynska, B; Wilczynski, H; Wolter, W; Wosiek, B; Wozniak, K

    1999-01-01

    A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in emulsion, and track geometry was analyzed. Charges of the fragments of heavy projectiles were estimated independently by the delta ray counting method. A calibration of both width and height of track profiles against ion charges was made with ions of known charges ranging from helium to gold nuclei. (author)

  15. Measurement of charge of heavy ions in emulsion using a CCD camera

    Energy Technology Data Exchange (ETDEWEB)

    Kudzia, D.; Cherry, M.L.; Dabrowska, A.; Deines-Jones, P.; Holynski, R.; Olszewski, A.; Nilsen, B.S.; Sengupta, K.; Szarska, M.; Trzupek, A.; Waddington, C.J.; Wefel, J.P.; Wilczynska, B.; Wilczynski, H. E-mail: henryk.wilczynski@ifj.edu.pl; Wolter, W.; Wosiek, B.; Wozniak, K

    1999-07-11

    A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in emulsion, and track geometry was analyzed. Charges of the fragments of heavy projectiles were estimated independently by the delta ray counting method. A calibration of both width and height of track profiles against ion charges was made with ions of known charges ranging from helium to gold nuclei. (author)

  16. Swift heavy ion irradiation induced electrical degradation in deca-nanometer MOSFETs

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yao; Yang, Zhimei; Gong, Min [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Gao, Bo; Li, Yun; Lin, Wei; Li, Jinbo; Xia, Zhuohui [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

    2016-09-15

    In this work, degradation of the electrical characteristics of 65 nm nMOSFETs under swift heavy ion irradiation is investigated. It was found that a heavy ion can generate a localized region of physical damage (ion latent track) in the gate oxide. This is the likely cause for the increased gate leakage current and soft breakdown (SBD) then hard breakdown (HBD) of the gate oxide. Except in the case of HBD, the devices retain their functionality but with degraded transconductance. The degraded gate oxide exhibits early breakdown behavior compatible with the model of defect generation and percolation path formation in the percolation model.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-08-08

    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.

  18. Isospin mixing in the nucleon and He-4 and the nucleon strange electric form-factor

    Energy Technology Data Exchange (ETDEWEB)

    M. Viviani; R. Schiavilla; B. Kubis; R. Lewis; L. Girlanda; A. Kievsky; L.E. Marcucci; S. Rosati

    2007-09-01

    In order to isolate the contribution of the nucleon strange electric form factor to the parity-violating asymmetry measured in 4He(\\vec e,e')4He experiments, it is crucial to have a reliable estimate of the magnitude of isospin-symmetry-breaking (ISB) corrections in both the nucleon and 4He. We examine this issue in the present letter. Isospin admixtures in the nucleon are determined in chiral perturbation theory, while those in 4He are derived from nuclear interactions, including explicit ISB terms. A careful analysis of the model dependence in the resulting predictions for the nucleon and nuclear ISB contributions to the asymmetry is carried out. We conclude that, at the low momentum transfers of interest in recent measurements reported by the HAPPEX collaboration at Jefferson Lab, these contributions are of comparable magnitude to those associated with strangeness components in the nucleon electric form factor.

  19. Non-destructive profile measurement of intensive heavy ion beams; Zerstoerungsfreie Profilmessung intensiver Schwerionenstrahlen

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Frank

    2010-02-08

    Within the framework of the FAIR-project (Facility for Antiproton and Ion Research) at GSI (Helmholtz Center for Heavy Ion Research), high intensity beams from protons to uranium ions with kinetic energies up to 30 AGeV are foreseen. Present GSI-accelerators like the UNILAC and the Heavy Ion Synchrotron (SIS-18) with a magnetic rigidity of 18 Tm will be used as injectors for the future synchrotron (SIS-100). Their beam current will be increased by up to two orders of magnitude. An accurate beam position and beam profile measurement is mandatory for a safe operation of transport sections, in particular in front of production targets (Fragment Separator (FRS)-target, anti p-production-target and Warm Dense Matter (WDM)-targets). Conventional intercepting profile monitors will not withstand the thermal stress of intensive ion beams, particularly for low energy applications or focused beams. For transverse profile determination a non-intercepting Beam Induced Fluorescence (BIF)-monitor was developed, working with residual gas. The BIF-monitor exploits fluorescence light emitted by residual gas molecules after atomic collisions with beam ions. Fluorescence-images were recorded with an image-intensified camera system, and beam profiles were obtained by projecting these images. Within the scope of this dissertation the following topics have been investigated: The photon yield, profile shape and background contribution were determined for different ion species (H{sup +}, S{sup 6+}, Ar{sup 18+}, K{sup +}, Ni{sup 9+}, Xe{sup 48+}, Ta{sup 24+}, Au{sup 65+}, U{sup 73+}), beam energies (7.7 AkeV-750 AMeV), gas pressures (10{sup -6}-3 mbar) and gas species (N{sub 2}, He, Ne, Ar, Kr, Xe). Applying an imaging spectrograph and narrowband 10 nm interference filters, the spectral response was mapped and associated with the corresponding gas transitions. Spectrally resolved beam profiles were also obtained form the spectrographic images. Major results are the light yield showing a

  20. Studies of Limits on Uncontrolled Heavy Ion Beam Losses for Allowing Hands-On Maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Reginald M. Ronningen; Igor Remec

    2010-09-11

    Dose rates from accelerator components activated by 1 W/m beam losses are obtained semiempirically for a 1 GeV proton beam and by use of Monte Carlo transport codes for the proton beam and for 777 MeV/u 3He, 500 MeV/u 48Ca, 86Kr, 136Xe, and 400 MeV/u 238U ions. The dose rate obtained by the semi-empirical method, 0.99 mSv/h (99 mrem/h) at 30 cm, 4 h after 100 d irradiation by a 1-GeV proton beam, is consistent with studies at several accelerator facilities and with adopted hands-on maintenance dose rate limits. Monte Carlo simulations verify this result for protons and extend studies to heavy ion beam losses in drift-tube linac and superconducting linac accelerating structures. The studies indicate that the 1 W/m limit imposed on uncontrolled beam losses for high-energy proton beams might be relaxed for heavy ion beams. These studies further suggest that using the ratio of neutrons produced by a heavy ion beam to neutrons produced by a proton beam along with the dose rate from the proton beam (for thin-target scenarios) should allow an estimate of the dose rates expected from heavy ion beam losses.

  1. Energy of vanishing flow in heavy-ion collisions: Role of mass ...

    Indian Academy of Sciences (India)

    Energy of vanishing flow in heavy-ion collisions: Role of mass asymmetry of a reaction. VARINDERJIT KAUR and SUNEEL KUMAR. ∗. School of Physics and Material Science, Thapar University, Patiala 147 004, India. ∗. Corresponding author. E-mail: suneel.kumar@thapar.edu. MS received 28 April 2011; revised 4 July ...

  2. Collective flows in high-energy heavy-ion collisions at AGS and SPS ...

    Indian Academy of Sciences (India)

    Abstract. Proton collective flows in heavy-ion collisions from AGS ((2–11) A GeV) to. SPS ((40, 158) A GeV) energies are investigated in a nonequilibrium transport model with nuclear mean-field (MF). Sideward 〈px〉, directed v1, and elliptic v2 flows are systematically studied with different assumptions on the nuclear ...

  3. Vacuum System Performance for the First Sextant Test of the Relativistic Heavy Ion Collider

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hseuh, H. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pate, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smart, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Todd, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Weiss, D. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    1997-10-14

    One of the major milestones during the construction of the Relativistic Heavy Ion Collider (RHIC) is the completion and successful testing of the first one sixth of the ring. This report summarizes the performance of the vacuum systems as it relates to the First Sextant Test (FST), and the design changes which precipitated.

  4. MEGHNAD–A multi element detector array for heavy ion collision ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... In the coming decade, the expanding field of experimental nuclear physics in our country is going to see a quantum leap in research and developmental activities with new accelerator facilities like the variable energy cyclotron with ECR heavy ion source, the upcoming K-500 superconducting cyclotron, ...

  5. Improved ion guide for heavy-ion fusion-evaporation reactions

    NARCIS (Netherlands)

    Dendooven, P; Beraud, R; Chabanat, E; Emsallem, A; Honkanen, A; Huhta, M; Jokinen, A; Lhersonneau, G; Oinonen, M; Penttila, H; Perajarvi, K; Wang, J.C.; Aysto, J

    1998-01-01

    The ion guide for heavy-ion-induced reactions developed originally for the SARA facility in Grenoble has been implemented at the Jyvaskyla IGISOL facility. For the Cd-116(Ar-40, 6n)Dy-150 reaction an efficiency of 0.5% relative to the number of reaction products entering the stopping chamber was

  6. Photon and dilepton production in high-energy heavy-ion collisions

    Indian Academy of Sciences (India)

    2015-05-07

    May 7, 2015 ... Hard production of photons and dileptons. One of the big successes in electromagnetic radiation measurements in relativistic heavy- ion collisions is the observation of high pT direct photons that are produced in the initial hard scattering [9]. Figures 4a and 4b show the latest direct photon pT spectra in Au+ ...

  7. LHCb Physics Motivations for the 2016 Heavy-ion LHC run

    CERN Document Server

    Graziani, Giacomo; Robbe, Patrick; Schmelling, Michael; Schmidt, Burkhard

    2016-01-01

    This document summarizes the arguments to support the request by the LHCb experiment to record an integrated luminosity of 20nb$^-1$ of $p$Pb and Pb$p$ collisions during the LHC heavy ion run of 2016 at a centre-of-mass energy of $\\sqrt{s_{\\rm NN}}=8$ TeV.

  8. From Full Stopping to Transparency in a Holographic Model of Heavy Ion Collisions

    NARCIS (Netherlands)

    Casalderrey-Solana, J.; Heller, M.P.; Mateos, D.; van der Schee, W.|info:eu-repo/dai/nl/330953974

    2013-01-01

    We numerically simulate planar shock wave collisions in anti–de Sitter space as a model for heavy ion collisions of large nuclei. We uncover a crossover between two different dynamical regimes as a function of the collision energy. At low energies the shocks first stop and then explode in a manner

  9. The First LHC p-Pb Run: Performance of the Heavy Ion Production Complex

    CERN Document Server

    Manglunki, D; Bartosik, H; Bellodi, G; Blas, A; Bodendorfer, M; Bohl, T; Carli, C; Carlier, E; Cettour-Cave, S; Cornelis, K; Damerau, H; Findlay, A; Gilardoni, S; Hancock, S; Jowett, J; Küchler, D; O'Neil, M; Papaphilippou, Y; Pasinelli, S; Scrivens, R; Tranquille, G; Vandorpe, B; Wehrle, U; Wenninger, J

    2013-01-01

    The first LHC proton-ion run took place in January-February 2013; it was the first extension to the collider programme, as this mode was not included in the design report. This paper presents the performance of the heavy ion and proton production complex, and details the issues encountered, in particular the creation of the same bunch pattern in both beams.

  10. Spatial Wilson loops in the classical field of high-energy heavy-ion collisions

    NARCIS (Netherlands)

    Petreska, Elena

    2014-01-01

    It has been previously shown numerically that the expectation value of the magnetic Wilson loop at the initial time of a heavy-ion collision exhibits area law scaling. This was obtained for a classical non-Abelian gauge field in the forward light cone and for loops of area $A\\gtrsim 2/Q_s^2$. Here,

  11. Time-of-flight measurements of heavy ions using Si PIN diodes

    Energy Technology Data Exchange (ETDEWEB)

    Strekalovsky, A. O., E-mail: alex.strek@bk.ru; Kamanin, D. V. [Joint Institute for Nuclear Research (Russian Federation); Pyatkov, Yu. V. [National Nuclear Research University MEPhI (Moscow Engineering Physics Institute) (Russian Federation); Kondratyev, N. A.; Zhuchko, V. E. [Joint Institute for Nuclear Research (Russian Federation); Ilić, S. [University of Novi Sad (Serbia); Alexandrov, A. A.; Alexandrova, I. A. [Joint Institute for Nuclear Research (Russian Federation); Jacobs, N. [University of Stellenbosch, Faculty of Military Science, Military Academy (South Africa); Kuznetsova, E. A.; Mishinsky, G. V.; Strekalovsky, O. V. [Joint Institute for Nuclear Research (Russian Federation)

    2016-12-15

    A new off-line timing method for PIN diode signals is presented which allows the plasma delay effect to be suppressed. Velocities of heavy ions measured by the new method are in good agreement within a wide range of masses and energies with velocities measured by time stamp detectors based on microchannel plates.

  12. Jet and Leading Hadron Production in High-energy Heavy-ionCollisions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin-Nian

    2005-11-01

    Jet tomography has become a powerful tool for the study ofproperties of dense matter in high-energy heavy-ion collisions. I willdiscuss recent progresses in the phenomenological study of jet quenching,including momentum, colliding energy and nuclear size dependence ofsingle hadron suppression, modification of dihadron correlations and thesoft hadron distribution associatedwith a quenched jet.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-11-01

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    MCLERRAN,L.; SAMIOS, N.

    2006-11-24

    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.

  15. Probing of complete and incomplete fusion dynamics in heavy-ion ...

    Indian Academy of Sciences (India)

    2014-04-04

    Apr 4, 2014 ... Heavy-ion induced reactions; complete and incomplete fusion; excitation functions; forward recoil range ... CF reaction the projectile completely fuses with the target nucleus and the highly excited compund nucleus .... higher charge precursor isobars 176W and 173Ta have been separated to obtain their.

  16. Light charged particle emission in heavy-ion reactions–What have ...

    Indian Academy of Sciences (India)

    Light charged particles emitted in heavy-ion induced reactions, their spectra and angular distributions measured over a range of energies, carry the signature of the underlying reaction mechanisms. Analysis of data of light charged particles, both inclusive and exclusive measured in coincidence with gamma rays, fission ...

  17. Dileptons and photons from central heavy-ion collisions at CERN-SPS

    CERN Document Server

    Kämpfer, B; Pavlenko, O P; Gale, C

    2002-01-01

    A unique parameterization of secondary (thermal) dilepton and photon yields in heavy-ion experiments at CERN-SPS is proposed. Adding those thermal yields to background contributions the spectral shapes of the CERES/NA45, NA38, NA50, HELIOS/3 and WA98 data from experiments with lead and sulfur beams can be well described.

  18. ATLAS One of the first Heavy ions collisions with stable beams- Event Display - November 2015

    CERN Multimedia

    ATLAS Collaboration

    2015-01-01

    One of the first heavy ions collisions with stable beams recorded by ATLAS in November 2015. Tracks reconstructed from hits in the inner tracking detector are shown as orange arcs curving in the solenoidal magnetic field. The green and yellow bars indicate energy deposits in the Liquid Argon and Scintillating Tile calorimeters respectively. The beam pipe and the inner detectors are also shown.

  19. Two-pion interferometry at small relative momentum in ultrarelativistic heavy ion collisions

    CERN Document Server

    Chen Xiao Fan; Chen Zhi Lai; Han Ling; Wang Qi

    2002-01-01

    The relations between the pion source parameters in two models in ultrarelativistic heavy ion collisions are given using pion interferometry at small relative momentum. And comparisons are made with the experimental results of 200A GeV O + Au collisions

  20. Phenotypic spectrum of Parachlorella kessleri (Chlorophyta) mutants produced by heavy-ion irradiation.

    Science.gov (United States)

    Ota, Shuhei; Matsuda, Takahiro; Takeshita, Tsuyoshi; Yamazaki, Tomokazu; Kazama, Yusuke; Abe, Tomoko; Kawano, Shigeyuki

    2013-12-01

    Heavy-ion mutagenesis is a technology used for effective production of genetic mutants. This study demonstrates that algal breeding using a unicellular alga, Parachlorella kessleri, by heavy-ion mutagenesis can improve lipid yield in laboratory experiments. The primary screening yielded 23 mutants among which a secondary screening yielded 7 strains, which were subjected to phenotypic assays. P. kessleri strains produced by heavy-ion radiation spanned a broad spectrum of phenotypes that differed in lipid content and fatty acid profiles. Starch grain morphology was distinctively altered in one of the mutants. The growth of strain PK4 was comparable to that of the wild type under stress-free culture conditions, and the mutant also produced large quantities of lipids, a combination of traits that may be of commercial interest. Thus, heavy-ion irradiation is an effective mutagenic agent for microalgae and may have potential in the production of strains with gain-of-function phenotypes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Schwinger Model and String Percolation in Hadron-Hadron and Heavy Ion Collisions

    OpenAIRE

    Dias De Deus, J; Ferreiro, E. G.; Pajares, C.; Ugoccioni, R.

    2003-01-01

    In the framework of the Schwinger Model for percolating strings we establish a general relation between multiplicity and transverse momentum square distributions in hadron-hadron and heavy ion collisions. Some of our results agree with the Colour Glass Condensate model.

  2. TWAC facility and the use of the laser ion source for production of intense heavy ion beams

    CERN Document Server

    Sharkov, B Yu; Shumshurov, A V; Meshcheryakov, N D; Rudskoy, I; Homenko, S; Makarov, K; Rörich, V; Stepanov, A; Satov, Yu A; Haseroth, H; Kugler, H; Lisi, N; Scrivens, R

    1999-01-01

    Current activities on upgrading of the ITEP heavy ion accelerator complex in the framework of the ITEP-TWAC project are reported. The project being in progress since 1997 is aiming at production of intense (100 kJ/100 ns) heavy ion beams. The basic idea of the project is the application of the non-Liouvillian technique in an existing accelerator facility based on a heavy ion synchrotron for its adaptation to heavy ion fusion related experiments. Special attention is paid to the results on generation of highly charged medium mass and heavy ions in the laser produced plasma. Development of key elements of the laser ion source based on the use of a 100 J repetition rate CO/sub 2/-laser for filling of ITEP and CERN accelerator facilities in the single turn injection mode is presented. (4 refs).

  3. Analyzing the Influence of the Angles of Incidence and Rotation on MBU Events Induced by Low LET Heavy Ions in a 28-nm SRAM-Based FPGA

    Science.gov (United States)

    Tonfat, Jorge; Kastensmidt, Fernanda Lima; Artola, Laurent; Hubert, Guillaume; Medina, Nilberto H.; Added, Nemitala; Aguiar, Vitor A. P.; Aguirre, Fernando; Macchione, Eduardo L. A.; Silveira, Marcilei A. G.

    2017-08-01

    This paper shows the impact of low linear energy transfer heavy ions on the reliability of 28-nm Bulk static random access memory (RAM) cells from Artix-7 field-programmable gate array. Irradiation tests on the ground showed significant differences in the multiple bit upset cross section of configuration RAM and block RAM memory cells under various angles of incidence and rotation of the device. Experimental data are analyzed at transistor level by using the single-event effect prediction tool called multiscale single-event phenomenon prediction platform coupled with SPICE simulations.

  4. Heavy-ion transport codes for radiotherapy and radioprotection in space

    Energy Technology Data Exchange (ETDEWEB)

    Mancusi, Davide

    2006-06-15

    Simulation of the transport of heavy ions in matter is a field of nuclear science that has recently received attention in view of its importance for some relevant applications. Accelerated heavy ions can, for example, be used to treat cancers (heavy-ion radiotherapy) and show some superior qualities with respect to more conventional treatment systems, like photons (x-rays) or protons. Furthermore, long-term manned space missions (like a possible future mission to Mars) pose the challenge to protect astronauts and equipment on board against the harmful space radiation environment, where heavy ions can be responsible for a significant share of the exposure risk. The high accuracy expected from a transport algorithm (especially in the case of radiotherapy) and the large amount of semi-empirical knowledge necessary to even state the transport problem properly rule out any analytical approach; the alternative is to resort to numerical simulations in order to build treatment-planning systems for cancer or to aid space engineers in shielding design. This thesis is focused on the description of HIBRAC, a one-dimensional deterministic code optimised for radiotherapy, and PHITS (Particle and Heavy- Ion Transport System), a general-purpose three-dimensional Monte-Carlo code. The structure of both codes is outlined and some relevant results are presented. In the case of PHITS, we also report the first results of an ongoing comprehensive benchmarking program for the main components of the code; we present the comparison of partial charge-changing cross sections for a 400 MeV/n {sup 40}Ar beam impinging on carbon, polyethylene, aluminium, copper, tin and lead targets.

  5. Relativistic extended Thomas-Fermi calculations of finite nuclei with realistic nucleon-nucleon interactions

    Energy Technology Data Exchange (ETDEWEB)

    Centelles, M.; Vinas, X.; Barranco, M. (Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain)); Ohtsuka, N.; Faessler, A.; Khoa, D.T.; Muether, H. (Institut fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-7400 Tuebingen (Germany))

    1993-03-01

    A relativistic energy density functional is constructed to investigate the Dirac effects on different properties of the structure and scattering of finite nuclei. The kinetic energy density has been derived within a relativistic extended Thomas-Fermi model and includes gradient corrections to second order in [h bar]. The effective mass and the volume term of the potential energy density have been obtained from a local density approximation to Dirac-Brueckner calculations of nuclear matter carried out with a realistic nucleon-nucleon interaction. This volume term is supplemented by the Coulomb energy and by conventional phenomenological surface and symmetry terms, and the few free parameters of the functional are suitably adjusted. Attention is then focused on the calculation of fission barriers of rotating nuclei and of the complex optical potential for heavy ion collisions at intermediate energies. It turns out that the effects of the density-dependent Dirac spinor which have been incorporated in this approach allow for a reasonable description of the investigated properties.

  6. Dynamics and collective behaviours in heavy ion collisions; Dynamique et comportements collectifs dans les collisions d`ions lourds

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, F. [Nantes Univ., 44 (France)

    1993-10-29

    This work is a contribution to the research domain of very high nuclear excitation obtained through fast rotation, extreme heating or high compression. To get precise quantitative information about the potentials governing the excited states decay the liquid drop model was utilized by taking into account the effects of nuclear proximity. In order to describe the heavy ion collision dynamics the nuclear microscopic and the semi-classical Landau-Vlasov approaches were adopted. The route to fission is studied through the superdeformed and hyper-deformed states of extremely high angular momenta and predictions for such states throughout the nuclear mass regions are set forth. The nuclear fragmentation mechanism and the fragmentation barriers are investigated starting from a generalization of the binary fission process and applying the generalized liquid drop model. By taking into account the oblate and prolate deformations, as well as the mass asymmetry, it was shown that the ternary process becomes competitive with the binary process in heavy nuclei while the prolate deformation is enhanced due to minimal Coulomb effects. The microscopic approach was applied in the case of {sup 100} Mo + {sup 100} Mo reactions at 18.7 MeV/n and {sup 40} Ar + {sup 107} Ag at 27 MeV/n and 44 MeV/n. A transition was made evident between highly inelastic processes and the fission following central collisions. A good fit with the experimental results was obtained by using a nucleon-nucleon cross section value equal to 1.5 {center_dot} {sigma}{sub free} or around {sigma}{sub free} corresponding to the two energy values, respectively. To estimate the contribution of different components to the total energy, the reaction Ar + Ar was studied showing different energy and impact parameter dependences of the thermal component corresponding to the source of thermal information. It is assumed that a better event reconstruction will result in a better understanding of the fragmentation phenomena

  7. Evidence for pair correlation effects in heavy ion reactions

    CERN Document Server

    Auditore, L; D'Amico, V; De Pasquale, D; Trifiró, A; Trimarchi, M; Italiano, A

    2003-01-01

    The study of the sup 1 sup 2 C( sup 1 sup 4 N, sup 1 sup 4 N) sup 1 sup 2 C reaction was performed at 28 and 35 MeV beam energies. The results were analyzed in the frame of the EFRDWBA (Exact-Finite-Range Distorted Wave Born Approximation) assuming the simultaneous and sequential transfer of a np pair. The angular distributions, fairly reproduced in the first case, confirm the validity of the generalized BCS (Bardeen-Cooper-Schrieffer) theory to explain this behaviour. Moreover, this process could be regarded as a possible Nuclear Josephson Effect. (author)

  8. Epigenetic Analysis of Heavy-ion Radiation Induced Bystander Effects in Mice

    Science.gov (United States)

    Zhang, Meng; Sun, Yeqing; Cui, Changna; Xue, Bei

    Abstract: Radiation-induced bystander effect was defined as the induction of damage in neighboring non-hit cells by signals released from directly-irradiated cells. Recently, low dose of high LET radiation induced bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. Genomic, epigenetic and proteomics plays significant roles in regulating heavy-ion radiation stress responses in mice. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male Balb/c and C57BL mice were exposed head-only to 40, 200, 2000mGy dose of (12) C heavy-ion radiation, while the rest of the animal body was shielded. Directly radiation organ ear and the distant organ liver were detected on 1h, 6h, 12h and 24h after radiation, respectively. Methylation-sensitive amplification polymorphism (MSAP) was used to monitor the level of polymorphic genomic DNA methylation changed with dose and time effects. The results show that heavy-ion irradiated mouse head could induce genomic DNA methylation changes significantly in both the directly radiation organ ear and the distant organ liver. The percent of DNA methylation changes were time-dependent and tissue-specific. Demethylation polymorphism rate was highest separately at 1 h in 200 mGy and 6 h in 2000 mGy after irradiation. The global DNA methylation changes tended to occur in the CG sites. The results illustrated that genomic methylation changes of heavy ion radiation-induced bystander effect in liver could be obvious 1 h after radiation and achieved the maximum at 6 h, while the changes could recover gradually at 12 h. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in both directly radiation organ ear and distant organ liver. Moreover, our findings are important to understand the molecular mechanism of

  9. Energy and centrality dependence of dN{sub ch}/dη and dE{sub T}/dη in heavy-ion collisions from √(s{sub NN}) = 7.7 GeV to 5.02 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Nath Mishra, Aditya; Sahoo, Raghunath; Sahoo, Pragati; Pareek, Pooja; Behera, Nirbhay K. [Indian Institute of Technology Indore, Discipline of Physics, School of Basic Sciences, Indore (India); Nandi, Basanta K. [Indian Institute of Technology Bombay, Department of Physics, Mumbai (India)

    2016-10-15

    The centrality dependence of pseudorapidity density of charged particles and transverse energy is studied for a wide range of collision energies for heavy-ion collisions at midrapidity from 7.7 GeV to 5.02TeV. A two-component model approach has been adopted to quantify the soft and hard components of particle production, coming from nucleon participants and binary nucleon-nucleon collisions, respectively. Within experimental uncertainties, the hard component contributing to the particle production has been found not to show any clear collision energy dependence from RHIC to LHC. The effect of centrality and collision energy in particle production seems to factor out with some degree of dependency on the collision species. The collision of uranium-like deformed nuclei opens up new challenges in understanding the energy-centrality factorization, which is evident from the centrality dependence of transverse energy density, when compared to collision of symmetric nuclei. (orig.)

  10. Nanolesions induced by heavy ions in human tissues: Experimental and theoretical studies

    Directory of Open Access Journals (Sweden)

    Marcus Bleicher

    2012-07-01

    Full Text Available The biological effects of energetic heavy ions are attracting increasing interest for their applications in cancer therapy and protection against space radiation. The cascade of events leading to cell death or late effects starts from stochastic energy deposition on the nanometer scale and the corresponding lesions in biological molecules, primarily DNA. We have developed experimental techniques to visualize DNA nanolesions induced by heavy ions. Nanolesions appear in cells as “streaks” which can be visualized by using different DNA repair markers. We have studied the kinetics of repair of these “streaks” also with respect to the chromatin conformation. Initial steps in the modeling of the energy deposition patterns at the micrometer and nanometer scale were made with MCHIT and TRAX models, respectively.

  11. Machine and deep learning techniques in heavy-ion collisions with ALICE arXiv

    CERN Document Server

    INSPIRE-00382877

    Over the last years, machine learning tools have been successfully applied to a wealth of problems in high-energy physics. A typical example is the classification of physics objects. Supervised machine learning methods allow for significant improvements in classification problems by taking into account observable correlations and by learning the optimal selection from examples, e.g. from Monte Carlo simulations. Even more promising is the usage of deep learning techniques. Methods like deep convolutional networks might be able to catch features from low-level parameters that are not exploited by default cut-based methods. These ideas could be particularly beneficial for measurements in heavy-ion collisions, because of the very large multiplicities. Indeed, machine learning methods potentially perform much better in systems with a large number of degrees of freedom compared to cut-based methods. Moreover, many key heavy-ion observables are most interesting at low transverse momentum where the underlying event ...

  12. Localized Beampipe Heating due to $e^{-}$ Capture and Nuclear Excitation in Heavy Ion Colliders

    CERN Document Server

    Klein, S R

    2001-01-01

    At heavy ion colliders, two major sources of beam loss are expected to be $e^+e^-$ production, where the $e^-$ is bound to one of the nuclei, and photonuclear excitation and decay via neutron emission. Both processes alter the ions charged to mass ratio by well defined amounts, creating beams of particles with altered magnetic rigidity. These beams will deposit their energy in a localized region of the accelerator, causing localized heating, The size of the target region depends on the collider optics. For medium and heavy ions, at design luminosity at the Large Hadron Collider, local heating may be more than an order of magnitude higher than expected. This could cause magnet quenches if the local cooling is inadequate. The altered-rigidity beams will also produce localized radiation damage. The beams could also be extracted and used for fixed target experiments.

  13. Jet Energy Scale and its Uncertainties using the Heavy Ion Jet Reconstruction Algorithm in pp Collisions

    CERN Document Server

    Puri, Akshat; The ATLAS collaboration

    2017-01-01

    ATLAS uses a jet reconstruction algorithm in heavy ion collisions that takes as input calorimeter towers of size $0.1 \\times \\pi/32$ in $\\Delta\\eta \\times \\Delta\\phi$ and iteratively determines the underlying event background. This algorithm, which is different from the standard jet reconstruction used in ATLAS, is also used in the proton-proton collisions used as reference data for the Pb+Pb and p+Pb. This poster provides details of the heavy ion jet reconstruction algorithm and its performance in pp collisions. The calibration procedure is described in detail and cross checks using photon- jet balance are shown. The uncertainties on the jet energy scale and the jet energy resolution are described.

  14. Evaluation of base materials of TL slab dosimeter for heavy-ion radiotherapy

    Science.gov (United States)

    Koba, Yusuke; Shinsho, Kiyomitsu; Tamatsu, Satoshi; Fukuda, Shigekazu; Wakabayashi, Genichiro

    2014-01-01

    In order to measure a three-dimensional dose distribution in X-ray radiotherapy, we developed TL slab dosimeter with new TL phosphor Li3B7O12(Cu), which has Zeff = 7.42 and a density of 1.01 g/cm3 and synthetic resin as binder [ 1]. We can measure a three-dimensional dose distribution easily and reliably using this detector. This detector showed a promising tool for QA/QC in advanced X-ray radiotherapies such as IMRT, etc. In heavy-ion radiotherapies which shape precipitous dose distributions, it is also necessary to measure three-dimensional dose distribution easily. To use TL slab dosimeter in heavy-ion dosimetry, it is essential to measure its LET dependence sufficiently. And it is necessary to evaluate the dosimetric water equivalence of this dosimeter for heavy ions. Previous studies showed that the relative TL efficiency of this TL phosphor decreased to ∼20% at the Bragg-peak of carbon 290 MeV/u beams and the stopping-power ratio of this dosimeter to water for carbon ions was 0.87 [ 2]. These results were not good for application in heavy-ion radiotherapy. It was often reported that there is a relationship between the glow curve shape of general TLDs (such as LiF and BeO) and LET. Using this relationship of glow curve and LET, the relative TL efficiency can be corrected and we could apply TLDs to dose measurement in heavy-ion radiotherapies. In this study, in order to develop better TL slab dosimeter for heavy-ion radiotherapy using TL phosphors with the above characteristics, we evaluated the dosimetric water equivalence of several base materials for TL slab dosimeter. We chose several kinds of ceramics with heating resistance as the base material; ISOPLATON E3, P1, M2, A98 S1 and Machinable Ceramics, TBS N64, N66, N1, N3 (ISOLITE Co., Ltd). We focused attention on stopping power, scattering power and nuclear cross-section of these materials for heavy ions. We calculated these interactions using the Bethe formula, the Gottschalk formula and the Sihver

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-05-16

    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.

  16. Stability of longitudinal bunch length feedback for heavy-ion synchrotrons

    Directory of Open Access Journals (Sweden)

    D. Lens

    2013-03-01

    Full Text Available In heavy-ion synchrotrons such as the SIS18 at Helmholtzzentrum für Schwerionenforschung, Helmholtz Centre for Heavy Ion Research (GSI, coherent oscillations of the particle bunches are damped by rf feedback systems to increase the stability and to improve the beam quality. In the longitudinal direction, important modes are the coherent longitudinal dipole and quadrupole oscillation. In this paper we present a new and rigorous approach to analyze the longitudinal feedback to damp these modes. The results are applied to the rf feedback loop at GSI that damps the quadrupole mode. The stability analysis is compared with simulations and is in good agreement with results of a beam experiment. Finally, we summarize practical implications for the operation of the feedback system regarding performance and stability.

  17. Relativistic Hydrodynamics in Heavy-Ion Collisions: General Aspects and Recent Developments

    Directory of Open Access Journals (Sweden)

    Amaresh Jaiswal

    2016-01-01

    Full Text Available Relativistic hydrodynamics has been quite successful in explaining the collective behaviour of the QCD matter produced in high energy heavy-ion collisions at RHIC and LHC. We briefly review the latest developments in the hydrodynamical modeling of relativistic heavy-ion collisions. Essential ingredients of the model such as the hydrodynamic evolution equations, dissipation, initial conditions, equation of state, and freeze-out process are reviewed. We discuss observable quantities such as particle spectra and anisotropic flow and effect of viscosity on these observables. Recent developments such as event-by-event fluctuations, flow in small systems (proton-proton and proton-nucleus collisions, flow in ultracentral collisions, longitudinal fluctuations, and correlations and flow in intense magnetic field are also discussed.

  18. Hunting down the quark-gluon plasma in relativistic heavy-ion collisions

    CERN Document Server

    Heinz, Ulrich W

    1999-01-01

    The present status of the heavy-ion program to search for quark-gluon plasma is reviewed. The goal of this program is to recreate the Big Bang in the laboratory, by generating small chunks of exploding quark-gluon plasma (``The Little Bang''). I argue that the analogues of the three pillars of Big Bang Theory (Hubble flow, microwave background radiation, and primordial nucleosynthesis) have now been firmly established in heavy-ion collisions at SPS energies: there is convincing evidence for strong radial flow, thermal hadron emission, and primordial hadrosynthesis from a color-deconfined initial stage. Direct observation of the quark-gluon plasma phase via its electromagnetic radiation will be possible in planned collider experiments at higher energies.

  19. Heavy ion time-of-flight ERDA of high dose metal implanted germanium

    Energy Technology Data Exchange (ETDEWEB)

    Dytlewski, N.; Evans, P.J.; Noorman, J.T. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Wielunski, L.S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics; Bunder, J. [New South Wales Univ., Wollongong, NSW (Australia). Wollongong Univ. Coll

    1996-12-31

    With the thick Ge substrates used in ion implantation, RBS can have difficulty in resolving the mass-depth ambiguities when analysing materials composed of mixtures of elements with nearly equal masses. Additional, and complimentary techniques are thus required. This paper reports the use of heavy ion time-of-flight elastic recoil detection analysis (ToF- ERDA), and conventional RBS in the analysis of Ge(100) implanted with high dose Ti and Cu ions from a MEWA ion source . Heavy ion ToF ERDA has been used to resolve, and profile the implanted transition metal species, and also to study any oxygen incorporation into the sample resulting from the implantation, or subsequential reactions with air or moisture. This work is part of a study on high dose metal ion implantation of medium atomic weight semiconductor materials. 13 refs., 6 figs.

  20. Probing the nuclear equation-of-state and the symmetry energy with heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Verde Giuseppe

    2014-03-01

    Full Text Available The present status of studies aimed at constraining the nuclear equation of state with heavy-ion collision dynamics is presented. Multifragmentation phenomena, including their isotopic distributions, charge correlations and emission time-scales, may revel the existence of liquid-gas transitions in the phase diagram. Exploring the isotopic degree of freedom in nuclear dynamics is then required in order to constrain the equation of state of asymmetric nuclear matter which presently represents a major priority due to its relevance to both nuclear physics and astrophysics. Some observables that have successfully constrained the density dependence of the symmetry energy are presented, such as neutron-proton yield ratios and isospin diffusion and drift phenomena. The reported results and status of the art is discussed by also considering some of the present problems and some future perspectives for the heavy-ion collision community.